x86, setup: reorgize the early_console_setup

Quoted 1 line · Yinghai Lu

also make main.c to include printf.c/string.c/cmdline.c

No. We don't include .c files that way.

-hpa

Signature · 2 lines

H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.

H. Peter Anvin

reviewer

2010-08-02 07:19 UTC #27 lore raw

Quoted 6 lines · Yinghai Lu

Seperate early_console_setup from tty.c
also make main.c to include printf.c/string.c/cmdline.c
will reuse early_serial_console.c/string.c/printf.c/cmdline.c in compressed/misc.c

The way to reuse files in boot/compressed/ would be just to create .c files in boot/compressed/ with, for example:

/* string.c */
#include "../string.c"

-hpa

Signature · 2 lines

H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.

Yinghai Lu

author

2010-08-02 08:25 UTC #3 lore raw

PATCH 1/2 x86, setup: reorgize the early_console_setup

Seperate early_serial_console from tty.c

will reuse early_serial_console.c/string.c/printf.c/cmdline.c in compressed/misc.c

-v2: according to hpa, don't include string.c etc.

Signed-off-by Yinghai Lu <[email protected]>

---
 arch/x86/boot/Makefile               |    8 -
 arch/x86/boot/boot.h                 |   35 ++++----
 arch/x86/boot/cmdline.c              |    6 -
 arch/x86/boot/early_serial_console.c |  141 +++++++++++++++++++++++++++++++++++
 arch/x86/boot/isdigit.h              |   21 +++++
 arch/x86/boot/printf.c               |    4 
 arch/x86/boot/tty.c                  |  136 ---------------------------------
 7 files changed, 187 insertions(+), 164 deletions(-)

arch/x86/boot/tty.c +0 ~~-136~~

Index: linux-2.6/arch/x86/boot/tty.c
===================================================================
@@ -15,27 +15,10 @@
 
 #include "boot.h"
 
-#define DEFAULT_SERIAL_PORT 0x3f8 /* ttyS0 */
-
-static int	early_serial_base;
-
 #define XMTRDY          0x20
 
-#define DLAB		0x80
-
 #define TXR             0       /*  Transmit register (WRITE) */
-#define RXR             0       /*  Receive register  (READ)  */
-#define IER             1       /*  Interrupt Enable          */
-#define IIR             2       /*  Interrupt ID              */
-#define FCR             2       /*  FIFO control              */
-#define LCR             3       /*  Line control              */
-#define MCR             4       /*  Modem control             */
 #define LSR             5       /*  Line Status               */
-#define MSR             6       /*  Modem Status              */
-#define DLL             0       /*  Divisor Latch Low         */
-#define DLH             1       /*  Divisor latch High        */
-
-#define DEFAULT_BAUD 9600
 
 /*
  * These functions are in .inittext so they can be used to signal

@@ -152,122 +135,3 @@ int getchar_timeout(void)
 	return 0;		/* Timeout! */
 }
 
-static void early_serial_init(int port, int baud)
-{
-	unsigned char c;
-	unsigned divisor;
-
-	outb(0x3, port + LCR);	/* 8n1 */
-	outb(0, port + IER);	/* no interrupt */
-	outb(0, port + FCR);	/* no fifo */
-	outb(0x3, port + MCR);	/* DTR + RTS */
-
-	divisor	= 115200 / baud;
-	c = inb(port + LCR);
-	outb(c | DLAB, port + LCR);
-	outb(divisor & 0xff, port + DLL);
-	outb((divisor >> 8) & 0xff, port + DLH);
-	outb(c & ~DLAB, port + LCR);
-
-	early_serial_base = port;
-
-	printf("Early serial console at I/O port 0x%x baud: %d\n", port, baud);
-}
-
-static void parse_earlyprintk(void)
-{
-	int baud = DEFAULT_BAUD;
-	char arg[32];
-	int pos = 0;
-	int port = 0;
-
-	if (cmdline_find_option("earlyprintk", arg, sizeof arg) > 0) {
-		char *e;
-
-		if (!strncmp(arg, "serial", 6)) {
-			port = DEFAULT_SERIAL_PORT;
-			pos += 6;
-		}
-
-		if (arg[pos] == ',')
-			pos++;
-
-		if (!strncmp(arg, "ttyS", 4)) {
-			static const int bases[] = { 0x3f8, 0x2f8 };
-			int idx = 0;
-
-			if (!strncmp(arg + pos, "ttyS", 4))
-				pos += 4;
-
-			if (arg[pos++] == '1')
-				idx = 1;
-
-			port = bases[idx];
-		}
-
-		if (arg[pos] == ',')
-			pos++;
-
-		baud = simple_strtoull(arg + pos, &e, 0);
-		if (baud == 0 || arg + pos == e)
-			baud = DEFAULT_BAUD;
-	}
-
-	if (port)
-		early_serial_init(port, baud);
-}
-
-#define BASE_BAUD (1843200/16)
-static unsigned int probe_baud(int port)
-{
-	unsigned char lcr, dll, dlh;
-	unsigned int quot;
-
-	lcr = inb(port + LCR);
-	outb(lcr | DLAB, port + LCR);
-	dll = inb(port + DLL);
-	dlh = inb(port + DLH);
-	outb(lcr, port + LCR);
-	quot = (dlh << 8) | dll;
-
-	return BASE_BAUD / quot;
-}
-
-static void parse_console_uart8250(void)
-{
-	char optstr[64], *options;
-	int baud = DEFAULT_BAUD;
-	int port = 0;
-
-	/*
-	 * console=uart8250,io,0x3f8,115200n8
-	 * need to make sure it is last one console !
-	 */
-	if (cmdline_find_option("console", optstr, sizeof optstr) <= 0)
-		return;
-
-	options = optstr;
-
-	if (!strncmp(options, "uart8250,io,", 12))
-		port = simple_strtoull(options + 12, &options, 0);
-	else if (!strncmp(options, "uart,io,", 8))
-		port = simple_strtoull(options + 8, &options, 0);
-	else
-		return;
-
-	if (options && (options[0] == ','))
-		baud = simple_strtoull(options + 1, &options, 0);
-	else
-		baud = probe_baud(port);
-
-	if (port)
-		early_serial_init(port, baud);
-}
-
-void console_init(void)
-{
-	parse_earlyprintk();
-
-	if (!early_serial_base)
-		parse_console_uart8250();
-}

arch/x86/boot/early_serial_console.c new file +141 -0

141 lines not on this page · raw message

arch/x86/boot/printf.c +2 -2

Index: linux-2.6/arch/x86/boot/printf.c
===================================================================
@@ -34,7 +34,7 @@ static int skip_atoi(const char **s)
 #define SMALL	32		/* Must be 32 == 0x20 */
 #define SPECIAL	64		/* 0x */
 
-#define do_div(n,base) ({ \
+#define __do_div(n, base) ({ \
 int __res; \
 __res = ((unsigned long) n) % (unsigned) base; \
 n = ((unsigned long) n) / (unsigned) base; \

@@ -83,7 +83,7 @@ static char *number(char *str, long num,
 		tmp[i++] = '0';
 	else
 		while (num != 0)
-			tmp[i++] = (digits[do_div(num, base)] | locase);
+			tmp[i++] = (digits[__do_div(num, base)] | locase);
 	if (i > precision)
 		precision = i;
 	size -= precision;

arch/x86/boot/cmdline.c +2 -4

Index: linux-2.6/arch/x86/boot/cmdline.c
===================================================================
@@ -27,9 +27,8 @@ static inline int myisspace(u8 c)
  * Returns the length of the argument (regardless of if it was
  * truncated to fit in the buffer), or -1 on not found.
  */
-int cmdline_find_option(const char *option, char *buffer, int bufsize)
+int __cmdline_find_option(u32 cmdline_ptr, const char *option, char *buffer, int bufsize)
 {
-	u32 cmdline_ptr = boot_params.hdr.cmd_line_ptr;
 	addr_t cptr;
 	char c;
 	int len = -1;

@@ -100,9 +99,8 @@ int cmdline_find_option(const char *opti
  * Returns the position of that option (starts counting with 1)
  * or 0 on not found
  */
-int cmdline_find_option_bool(const char *option)
+int __cmdline_find_option_bool(u32 cmdline_ptr, const char *option)
 {
-	u32 cmdline_ptr = boot_params.hdr.cmd_line_ptr;
 	addr_t cptr;
 	char c;
 	int pos = 0, wstart = 0;

arch/x86/boot/Makefile +4 -4

Index: linux-2.6/arch/x86/boot/Makefile
===================================================================
@@ -26,10 +26,10 @@ targets		:= vmlinux.bin setup.bin setup.
 targets		+= fdimage fdimage144 fdimage288 image.iso mtools.conf
 subdir-		:= compressed
 
-setup-y		+= a20.o bioscall.o cmdline.o copy.o cpu.o cpucheck.o edd.o
-setup-y		+= header.o main.o mca.o memory.o pm.o pmjump.o
-setup-y		+= printf.o regs.o string.o tty.o video.o video-mode.o
-setup-y		+= version.o
+setup-y		+= a20.o bioscall.o cmdline.o copy.o cpu.o cpucheck.o
+setup-y		+= early_serial_console.o edd.o header.o main.o mca.o memory.o
+setup-y		+= pm.o pmjump.o printf.o regs.o string.o tty.o video.o
+setup-y		+= video-mode.o version.o
 setup-$(CONFIG_X86_APM_BOOT) += apm.o
 
 # The link order of the video-*.o modules can matter.  In particular,

arch/x86/boot/boot.h +17 ~~-18~~

Index: linux-2.6/arch/x86/boot/boot.h
===================================================================
@@ -200,21 +200,7 @@ static inline int memcmp_gs(const void *
 	return diff;
 }
 
-static inline int isdigit(int ch)
-{
-	return (ch >= '0') && (ch <= '9');
-}
-
-static inline int isxdigit(int ch)
-{
-	if (isdigit(ch))
-		return true;
-
-	if ((ch >= 'a') && (ch <= 'f'))
-		return true;
-
-	return (ch >= 'A') && (ch <= 'F');
-}
+#include "isdigit.h"
 
 /* Heap -- available for dynamic lists. */
 extern char _end[];

@@ -300,8 +286,18 @@ struct biosregs {
 void intcall(u8 int_no, const struct biosregs *ireg, struct biosregs *oreg);
 
 /* cmdline.c */
-int cmdline_find_option(const char *option, char *buffer, int bufsize);
-int cmdline_find_option_bool(const char *option);
+int __cmdline_find_option(u32 cmdline_ptr, const char *option, char *buffer, int bufsize);
+int __cmdline_find_option_bool(u32 cmdline_ptr, const char *option);
+static inline int cmdline_find_option(const char *option, char *buffer, int bufsize)
+{
+	return __cmdline_find_option(boot_params.hdr.cmd_line_ptr, option, buffer, bufsize);
+}
+
+static inline int cmdline_find_option_bool(const char *option)
+{
+	return __cmdline_find_option_bool(boot_params.hdr.cmd_line_ptr, option);
+}
+
 
 /* cpu.c, cpucheck.c */
 struct cpu_features {

@@ -313,6 +309,10 @@ extern struct cpu_features cpu;
 int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr);
 int validate_cpu(void);
 
+/* early_serial_console.c */
+extern int early_serial_base;
+void console_init(void);
+
 /* edd.c */
 void query_edd(void);

@@ -348,7 +348,6 @@ unsigned int atou(const char *s);
 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base);
 
 /* tty.c */
-void console_init(void);
 void puts(const char *);
 void putchar(int);
 int getchar(void);

arch/x86/boot/isdigit.h new file +21 -0

Index: linux-2.6/arch/x86/boot/isdigit.h
===================================================================
@@ -0,0 +1,21 @@
+#ifndef BOOT_ISDIGIT_H
+
+#define BOOT_ISDIGIT_H
+
+static inline int isdigit(int ch)
+{
+	return (ch >= '0') && (ch <= '9');
+}
+
+static inline int isxdigit(int ch)
+{
+	if (isdigit(ch))
+		return true;
+
+	if ((ch >= 'a') && (ch <= 'f'))
+		return true;
+
+	return (ch >= 'A') && (ch <= 'F');
+}
+
+#endif

Yinghai Lu

author

2010-08-02 08:27 UTC #26 lore raw

PATCH 2/2 x86: more early console output from compressed/misc.c

will get

|Decompressing Linux... Parsing ELF... done.
|Booting the kernel.

in serial console.

reuse code from arch/x86/boot/
and we can use printf if needed

-v2: define BOOT_BOOT_H to avoid include boot.h

Signed-off-by Yinghai Lu <[email protected]>

---
 arch/x86/boot/compressed/misc.c |   62 +++++++++++++++++++++++++++++++++++++++-
 1 file changed, 61 insertions(+), 1 deletion(-)

arch/x86/boot/compressed/misc.c +61 -1

Index: linux-2.6/arch/x86/boot/compressed/misc.c
===================================================================
@@ -125,12 +125,14 @@ static void error(char *m);
  */
 static struct boot_params *real_mode;		/* Pointer to real-mode data */
 static int quiet;
+static int debug;
 
 void *memset(void *s, int c, size_t n);
 void *memcpy(void *dest, const void *src, size_t n);
 
 static void __putstr(int, const char *);
 #define putstr(__x)  __putstr(0, __x)
+#define puts(__x)  __putstr(0, __x)
 
 #ifdef CONFIG_X86_64
 #define memptr long

@@ -145,6 +147,11 @@ static char *vidmem;
 static int vidport;
 static int lines, cols;
 
+#define BOOT_BOOT_H
+#include "../isdigit.h"
+#include "../string.c"
+#include "../printf.c"
+
 #ifdef CONFIG_KERNEL_GZIP
 #include "../../../../lib/decompress_inflate.c"
 #endif

@@ -161,6 +168,27 @@ static int lines, cols;
 #include "../../../../lib/decompress_unlzo.c"
 #endif
 
+static unsigned long fs;
+static inline void set_fs(unsigned long seg)
+{
+	fs = seg << 4;  /* shift it back */
+}
+typedef unsigned long addr_t;
+static inline char rdfs8(addr_t addr)
+{
+	return *((char *)(fs + addr));
+}
+#include "../cmdline.c"
+int cmdline_find_option(const char *option, char *buffer, int bufsize)
+{
+	return __cmdline_find_option(real_mode->hdr.cmd_line_ptr, option, buffer, bufsize);
+}
+int cmdline_find_option_bool(const char *option)
+{
+	return __cmdline_find_option_bool(real_mode->hdr.cmd_line_ptr, option);
+}
+#include "../early_serial_console.c"
+
 static void scroll(void)
 {
 	int i;

@@ -170,6 +198,16 @@ static void scroll(void)
 		vidmem[i] = ' ';
 }
 
+static void serial_putchar(int ch)
+{
+	unsigned timeout = 0xffff;
+
+	while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout)
+		cpu_relax();
+
+	outb(ch, early_serial_base + TXR);
+}
+
 static void __putstr(int error, const char *s)
 {
 	int x, y, pos;

@@ -179,6 +217,14 @@ static void __putstr(int error, const ch
 	if (!error)
 		return;
 #endif
+	if (early_serial_base) {
+		const char *str = s;
+		while (*str) {
+			if (*str == '\n')
+				serial_putchar('\r');
+			serial_putchar(*str++);
+		}
+	}
 
 	if (real_mode->screen_info.orig_video_mode == 0 &&
 	    lines == 0 && cols == 0)

@@ -305,8 +351,12 @@ asmlinkage void decompress_kernel(void *
 {
 	real_mode = rmode;
 
-	if (real_mode->hdr.loadflags & QUIET_FLAG)
+	if (cmdline_find_option_bool("quiet"))
 		quiet = 1;
+	if (cmdline_find_option_bool("debug"))
+		debug = 1;
+
+	console_init();
 
 	if (real_mode->screen_info.orig_video_mode == 7) {
 		vidmem = (char *) 0xb0000;

@@ -322,6 +372,16 @@ asmlinkage void decompress_kernel(void *
 	free_mem_ptr     = heap;	/* Heap */
 	free_mem_end_ptr = heap + BOOT_HEAP_SIZE;
 
+	if (debug) {
+		putstr("decompress_kernel:\n");
+		printf("  input: [0x%lx-0x%lx], output: 0x%lx, heap: [0x%lx-0x%lx]\n",
+			 (unsigned long)input_data,
+			 (unsigned long)input_data + input_len - 1,
+			 (unsigned long)output,
+			 (unsigned long)heap,
+			 (unsigned long)heap + BOOT_HEAP_SIZE - 1);
+	}
+
 	if ((unsigned long)output & (MIN_KERNEL_ALIGN - 1))
 		error("Destination address inappropriately aligned");
 #ifdef CONFIG_X86_64

Yinghai Lu

author

2010-08-02 09:18 UTC #4 lore raw

PATCH 1/2 x86, setup: reorgize the early_console_setup

Seperate early_serial_console from tty.c

will reuse early_serial_console.c/string.c/printf.c/cmdline.c in compressed/misc.c

-v2: according to hpa, don't include string.c etc
-v3: compressed/misc.c must have early_serial_base as static, so move it back to tty.c
for setup code

Signed-off-by Yinghai Lu <[email protected]>

---
 arch/x86/boot/Makefile               |    8 +-
 arch/x86/boot/boot.h                 |   35 ++++----
 arch/x86/boot/cmdline.c              |    6 -
 arch/x86/boot/early_serial_console.c |  139 +++++++++++++++++++++++++++++++++++
 arch/x86/boot/isdigit.h              |   21 +++++
 arch/x86/boot/printf.c               |    4 -
 arch/x86/boot/tty.c                  |  136 ----------------------------------
 7 files changed, 186 insertions(+), 163 deletions(-)

arch/x86/boot/tty.c +1 ~~-135~~

Index: linux-2.6/arch/x86/boot/tty.c
===================================================================
@@ -15,27 +15,12 @@
 
 #include "boot.h"
 
-#define DEFAULT_SERIAL_PORT 0x3f8 /* ttyS0 */
-
-static int	early_serial_base;
+int early_serial_base;
 
 #define XMTRDY          0x20
 
-#define DLAB		0x80
-
 #define TXR             0       /*  Transmit register (WRITE) */
-#define RXR             0       /*  Receive register  (READ)  */
-#define IER             1       /*  Interrupt Enable          */
-#define IIR             2       /*  Interrupt ID              */
-#define FCR             2       /*  FIFO control              */
-#define LCR             3       /*  Line control              */
-#define MCR             4       /*  Modem control             */
 #define LSR             5       /*  Line Status               */
-#define MSR             6       /*  Modem Status              */
-#define DLL             0       /*  Divisor Latch Low         */
-#define DLH             1       /*  Divisor latch High        */
-
-#define DEFAULT_BAUD 9600
 
 /*
  * These functions are in .inittext so they can be used to signal

@@ -152,122 +137,3 @@ int getchar_timeout(void)
 	return 0;		/* Timeout! */
 }
 
-static void early_serial_init(int port, int baud)
-{
-	unsigned char c;
-	unsigned divisor;
-
-	outb(0x3, port + LCR);	/* 8n1 */
-	outb(0, port + IER);	/* no interrupt */
-	outb(0, port + FCR);	/* no fifo */
-	outb(0x3, port + MCR);	/* DTR + RTS */
-
-	divisor	= 115200 / baud;
-	c = inb(port + LCR);
-	outb(c | DLAB, port + LCR);
-	outb(divisor & 0xff, port + DLL);
-	outb((divisor >> 8) & 0xff, port + DLH);
-	outb(c & ~DLAB, port + LCR);
-
-	early_serial_base = port;
-
-	printf("Early serial console at I/O port 0x%x baud: %d\n", port, baud);
-}
-
-static void parse_earlyprintk(void)
-{
-	int baud = DEFAULT_BAUD;
-	char arg[32];
-	int pos = 0;
-	int port = 0;
-
-	if (cmdline_find_option("earlyprintk", arg, sizeof arg) > 0) {
-		char *e;
-
-		if (!strncmp(arg, "serial", 6)) {
-			port = DEFAULT_SERIAL_PORT;
-			pos += 6;
-		}
-
-		if (arg[pos] == ',')
-			pos++;
-
-		if (!strncmp(arg, "ttyS", 4)) {
-			static const int bases[] = { 0x3f8, 0x2f8 };
-			int idx = 0;
-
-			if (!strncmp(arg + pos, "ttyS", 4))
-				pos += 4;
-
-			if (arg[pos++] == '1')
-				idx = 1;
-
-			port = bases[idx];
-		}
-
-		if (arg[pos] == ',')
-			pos++;
-
-		baud = simple_strtoull(arg + pos, &e, 0);
-		if (baud == 0 || arg + pos == e)
-			baud = DEFAULT_BAUD;
-	}
-
-	if (port)
-		early_serial_init(port, baud);
-}
-
-#define BASE_BAUD (1843200/16)
-static unsigned int probe_baud(int port)
-{
-	unsigned char lcr, dll, dlh;
-	unsigned int quot;
-
-	lcr = inb(port + LCR);
-	outb(lcr | DLAB, port + LCR);
-	dll = inb(port + DLL);
-	dlh = inb(port + DLH);
-	outb(lcr, port + LCR);
-	quot = (dlh << 8) | dll;
-
-	return BASE_BAUD / quot;
-}
-
-static void parse_console_uart8250(void)
-{
-	char optstr[64], *options;
-	int baud = DEFAULT_BAUD;
-	int port = 0;
-
-	/*
-	 * console=uart8250,io,0x3f8,115200n8
-	 * need to make sure it is last one console !
-	 */
-	if (cmdline_find_option("console", optstr, sizeof optstr) <= 0)
-		return;
-
-	options = optstr;
-
-	if (!strncmp(options, "uart8250,io,", 12))
-		port = simple_strtoull(options + 12, &options, 0);
-	else if (!strncmp(options, "uart,io,", 8))
-		port = simple_strtoull(options + 8, &options, 0);
-	else
-		return;
-
-	if (options && (options[0] == ','))
-		baud = simple_strtoull(options + 1, &options, 0);
-	else
-		baud = probe_baud(port);
-
-	if (port)
-		early_serial_init(port, baud);
-}
-
-void console_init(void)
-{
-	parse_earlyprintk();
-
-	if (!early_serial_base)
-		parse_console_uart8250();
-}

arch/x86/boot/early_serial_console.c new file +139 -0

139 lines not on this page · raw message

arch/x86/boot/printf.c +2 -2

Index: linux-2.6/arch/x86/boot/printf.c
===================================================================
@@ -34,7 +34,7 @@ static int skip_atoi(const char **s)
 #define SMALL	32		/* Must be 32 == 0x20 */
 #define SPECIAL	64		/* 0x */
 
-#define do_div(n,base) ({ \
+#define __do_div(n, base) ({ \
 int __res; \
 __res = ((unsigned long) n) % (unsigned) base; \
 n = ((unsigned long) n) / (unsigned) base; \

@@ -83,7 +83,7 @@ static char *number(char *str, long num,
 		tmp[i++] = '0';
 	else
 		while (num != 0)
-			tmp[i++] = (digits[do_div(num, base)] | locase);
+			tmp[i++] = (digits[__do_div(num, base)] | locase);
 	if (i > precision)
 		precision = i;
 	size -= precision;

arch/x86/boot/cmdline.c +2 -4

Index: linux-2.6/arch/x86/boot/cmdline.c
===================================================================
@@ -27,9 +27,8 @@ static inline int myisspace(u8 c)
  * Returns the length of the argument (regardless of if it was
  * truncated to fit in the buffer), or -1 on not found.
  */
-int cmdline_find_option(const char *option, char *buffer, int bufsize)
+int __cmdline_find_option(u32 cmdline_ptr, const char *option, char *buffer, int bufsize)
 {
-	u32 cmdline_ptr = boot_params.hdr.cmd_line_ptr;
 	addr_t cptr;
 	char c;
 	int len = -1;

@@ -100,9 +99,8 @@ int cmdline_find_option(const char *opti
  * Returns the position of that option (starts counting with 1)
  * or 0 on not found
  */
-int cmdline_find_option_bool(const char *option)
+int __cmdline_find_option_bool(u32 cmdline_ptr, const char *option)
 {
-	u32 cmdline_ptr = boot_params.hdr.cmd_line_ptr;
 	addr_t cptr;
 	char c;
 	int pos = 0, wstart = 0;

arch/x86/boot/Makefile +4 -4

Index: linux-2.6/arch/x86/boot/Makefile
===================================================================
@@ -26,10 +26,10 @@ targets		:= vmlinux.bin setup.bin setup.
 targets		+= fdimage fdimage144 fdimage288 image.iso mtools.conf
 subdir-		:= compressed
 
-setup-y		+= a20.o bioscall.o cmdline.o copy.o cpu.o cpucheck.o edd.o
-setup-y		+= header.o main.o mca.o memory.o pm.o pmjump.o
-setup-y		+= printf.o regs.o string.o tty.o video.o video-mode.o
-setup-y		+= version.o
+setup-y		+= a20.o bioscall.o cmdline.o copy.o cpu.o cpucheck.o
+setup-y		+= early_serial_console.o edd.o header.o main.o mca.o memory.o
+setup-y		+= pm.o pmjump.o printf.o regs.o string.o tty.o video.o
+setup-y		+= video-mode.o version.o
 setup-$(CONFIG_X86_APM_BOOT) += apm.o
 
 # The link order of the video-*.o modules can matter.  In particular,

arch/x86/boot/boot.h +17 ~~-18~~

Index: linux-2.6/arch/x86/boot/boot.h
===================================================================
@@ -200,21 +200,7 @@ static inline int memcmp_gs(const void *
 	return diff;
 }
 
-static inline int isdigit(int ch)
-{
-	return (ch >= '0') && (ch <= '9');
-}
-
-static inline int isxdigit(int ch)
-{
-	if (isdigit(ch))
-		return true;
-
-	if ((ch >= 'a') && (ch <= 'f'))
-		return true;
-
-	return (ch >= 'A') && (ch <= 'F');
-}
+#include "isdigit.h"
 
 /* Heap -- available for dynamic lists. */
 extern char _end[];

@@ -300,8 +286,18 @@ struct biosregs {
 void intcall(u8 int_no, const struct biosregs *ireg, struct biosregs *oreg);
 
 /* cmdline.c */
-int cmdline_find_option(const char *option, char *buffer, int bufsize);
-int cmdline_find_option_bool(const char *option);
+int __cmdline_find_option(u32 cmdline_ptr, const char *option, char *buffer, int bufsize);
+int __cmdline_find_option_bool(u32 cmdline_ptr, const char *option);
+static inline int cmdline_find_option(const char *option, char *buffer, int bufsize)
+{
+	return __cmdline_find_option(boot_params.hdr.cmd_line_ptr, option, buffer, bufsize);
+}
+
+static inline int cmdline_find_option_bool(const char *option)
+{
+	return __cmdline_find_option_bool(boot_params.hdr.cmd_line_ptr, option);
+}
+
 
 /* cpu.c, cpucheck.c */
 struct cpu_features {

@@ -313,6 +309,10 @@ extern struct cpu_features cpu;
 int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr);
 int validate_cpu(void);
 
+/* early_serial_console.c */
+extern int early_serial_base;
+void console_init(void);
+
 /* edd.c */
 void query_edd(void);

@@ -348,7 +348,6 @@ unsigned int atou(const char *s);
 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base);
 
 /* tty.c */
-void console_init(void);
 void puts(const char *);
 void putchar(int);
 int getchar(void);

arch/x86/boot/isdigit.h new file +21 -0

Index: linux-2.6/arch/x86/boot/isdigit.h
===================================================================
@@ -0,0 +1,21 @@
+#ifndef BOOT_ISDIGIT_H
+
+#define BOOT_ISDIGIT_H
+
+static inline int isdigit(int ch)
+{
+	return (ch >= '0') && (ch <= '9');
+}
+
+static inline int isxdigit(int ch)
+{
+	if (isdigit(ch))
+		return true;
+
+	if ((ch >= 'a') && (ch <= 'f'))
+		return true;
+
+	return (ch >= 'A') && (ch <= 'F');
+}
+
+#endif

Yinghai Lu

author

2010-08-02 09:19 UTC #5 lore raw

PATCH 2/2 x86: more early console output from compressed/misc.c

will get

|Decompressing Linux... Parsing ELF... done.
|Booting the kernel.

in serial console.

reuse code from arch/x86/boot/
and we can use printf if needed

-v2: define BOOT_BOOT_H to avoid include boot.h -v3: early_serial_base need to be static in misc.c ?

Signed-off-by Yinghai Lu <[email protected]>

---
 arch/x86/boot/compressed/misc.c |   65 +++++++++++++++++++++++++++++++++++++++-
 arch/x86/boot/main.c            |    6 +--
 2 files changed, 66 insertions(+), 5 deletions(-)

arch/x86/boot/compressed/misc.c +64 -1

Index: linux-2.6/arch/x86/boot/compressed/misc.c
===================================================================
@@ -125,12 +125,14 @@ static void error(char *m);
  */
 static struct boot_params *real_mode;		/* Pointer to real-mode data */
 static int quiet;
+static int debug;
 
 void *memset(void *s, int c, size_t n);
 void *memcpy(void *dest, const void *src, size_t n);
 
 static void __putstr(int, const char *);
 #define putstr(__x)  __putstr(0, __x)
+#define puts(__x)  __putstr(0, __x)
 
 #ifdef CONFIG_X86_64
 #define memptr long

@@ -145,6 +147,11 @@ static char *vidmem;
 static int vidport;
 static int lines, cols;
 
+#define BOOT_BOOT_H
+#include "../isdigit.h"
+#include "../string.c"
+#include "../printf.c"
+
 #ifdef CONFIG_KERNEL_GZIP
 #include "../../../../lib/decompress_inflate.c"
 #endif

@@ -161,6 +168,28 @@ static int lines, cols;
 #include "../../../../lib/decompress_unlzo.c"
 #endif
 
+static unsigned long fs;
+static inline void set_fs(unsigned long seg)
+{
+	fs = seg << 4;  /* shift it back */
+}
+typedef unsigned long addr_t;
+static inline char rdfs8(addr_t addr)
+{
+	return *((char *)(fs + addr));
+}
+#include "../cmdline.c"
+static inline int cmdline_find_option(const char *option, char *buffer, int bufsize)
+{
+	return __cmdline_find_option(real_mode->hdr.cmd_line_ptr, option, buffer, bufsize);
+}
+static inline int cmdline_find_option_bool(const char *option)
+{
+	return __cmdline_find_option_bool(real_mode->hdr.cmd_line_ptr, option);
+}
+static int early_serial_base;
+#include "../early_serial_console.c"
+
 static void scroll(void)
 {
 	int i;

@@ -170,6 +199,16 @@ static void scroll(void)
 		vidmem[i] = ' ';
 }
 
+static void serial_putchar(int ch)
+{
+	unsigned timeout = 0xffff;
+
+	while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout)
+		cpu_relax();
+
+	outb(ch, early_serial_base + TXR);
+}
+
 static void __putstr(int error, const char *s)
 {
 	int x, y, pos;

@@ -179,6 +218,14 @@ static void __putstr(int error, const ch
 	if (!error)
 		return;
 #endif
+	if (early_serial_base) {
+		const char *str = s;
+		while (*str) {
+			if (*str == '\n')
+				serial_putchar('\r');
+			serial_putchar(*str++);
+		}
+	}
 
 	if (real_mode->screen_info.orig_video_mode == 0 &&
 	    lines == 0 && cols == 0)

@@ -305,8 +352,10 @@ asmlinkage void decompress_kernel(void *
 {
 	real_mode = rmode;
 
-	if (real_mode->hdr.loadflags & QUIET_FLAG)
+	if (cmdline_find_option_bool("quiet"))
 		quiet = 1;
+	if (cmdline_find_option_bool("debug"))
+		debug = 1;
 
 	if (real_mode->screen_info.orig_video_mode == 7) {
 		vidmem = (char *) 0xb0000;

@@ -319,9 +368,23 @@ asmlinkage void decompress_kernel(void *
 	lines = real_mode->screen_info.orig_video_lines;
 	cols = real_mode->screen_info.orig_video_cols;
 
+	console_init();
+	if (debug)
+		putstr("early console in decompress_kernel\n");
+
 	free_mem_ptr     = heap;	/* Heap */
 	free_mem_end_ptr = heap + BOOT_HEAP_SIZE;
 
+	if (debug) {
+		putstr("decompress_kernel:\n");
+		printf("  input: [0x%lx-0x%lx], output: 0x%lx, heap: [0x%lx-0x%lx]\n",
+			 (unsigned long)input_data,
+			 (unsigned long)input_data + input_len - 1,
+			 (unsigned long)output,
+			 (unsigned long)heap,
+			 (unsigned long)heap + BOOT_HEAP_SIZE - 1);
+	}
+
 	if ((unsigned long)output & (MIN_KERNEL_ALIGN - 1))
 		error("Destination address inappropriately aligned");
 #ifdef CONFIG_X86_64

arch/x86/boot/main.c +2 -4

Index: linux-2.6/arch/x86/boot/main.c
===================================================================
@@ -132,6 +132,8 @@ void main(void)
 
 	/* Initialize the early-boot console */
 	console_init();
+	if (cmdline_find_option_bool("debug"))
+		puts("early console in setup code\n");
 
 	/* End of heap check */
 	init_heap();

@@ -171,10 +173,6 @@ void main(void)
 	/* Set the video mode */
 	set_video();
 
-	/* Parse command line for 'quiet' and pass it to decompressor. */
-	if (cmdline_find_option_bool("quiet"))
-		boot_params.hdr.loadflags |= QUIET_FLAG;
-
 	/* Do the last things and invoke protected mode */
 	go_to_protected_mode();
 }

Cyrill Gorcunov

2010-08-02 15:10 UTC #28 lore raw

Quoted 9 lines · Yinghai Lu

Seperate early_console_setup from tty.c
also make main.c to include printf.c/string.c/cmdline.c
will reuse early_serial_console.c/string.c/printf.c/cmdline.c in compressed/misc.c
Signed-off-by Yinghai Lu <[email protected]>
---

Hi Yinghai, I'll try to find some time for review though it looks somehow too 'big' for me :)

Actually by reading your initial approach (which was much smaller in size) I thought we end up in something like the patch below, though I'll review this seris. So just to share (I've tested it under qemu). The idea is the same as your was, so I pushed all constant parts into header and use it when needed passing serial line base port via boot_params.

---
 arch/x86/boot/boot.h             |    2 -
 arch/x86/boot/compressed/misc.c  |   18 +++++++++++++
 arch/x86/boot/main.c             |    2 -
 arch/x86/boot/tty.c              |   51 ++++++++++-----------------------------
 arch/x86/boot/tty.h              |   45 ++++++++++++++++++++++++++++++++++
 arch/x86/include/asm/bootparam.h |    2 -
 arch/x86/kernel/early_printk.c   |   36 +++------------------------
 7 files changed, 85 insertions(+), 71 deletions(-)

arch/x86/boot/boot.h +1 -1

Index: linux-2.6.git/arch/x86/boot/boot.h
=====================================================================
@@ -348,7 +348,7 @@ unsigned int atou(const char *s);
 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base);
 
 /* tty.c */
-void console_init(void);
+void console_init(struct boot_params *boot_params);
 void puts(const char *);
 void putchar(int);
 int getchar(void);

arch/x86/boot/compressed/misc.c +18 -0

Index: linux-2.6.git/arch/x86/boot/compressed/misc.c
=====================================================================
@@ -27,6 +27,8 @@
 #include <asm/boot.h>
 #include <asm/bootparam.h>
 
+#include "../tty.h"
+
 /* WARNING!!
  * This code is compiled with -fPIC and it is relocated dynamically
  * at run time, but no relocation processing is performed.

@@ -180,6 +182,21 @@ static void __putstr(int error, const ch
 		return;
 #endif
 
+	/*
+	 * write to  early serial console first
+	 * then we may write to video memory
+	 */
+	if (real_mode->early_serial_base) {
+		int ch, base = real_mode->early_serial_base;
+		const char *str = s;
+		while ((ch = *str++)) {
+			/* \n -> \r\n */
+			if (ch == '\n')
+				__serial_putchar('\r', base);
+			__serial_putchar(ch, base);
+		}
+	}
+
 	if (real_mode->screen_info.orig_video_mode == 0 &&
 	    lines == 0 && cols == 0)
 		return;

@@ -342,5 +359,6 @@ asmlinkage void decompress_kernel(void *
 	parse_elf(output);
 	if (!quiet)
 		putstr("done.\nBooting the kernel.\n");
+
 	return;
 }

arch/x86/boot/main.c +1 -1

Index: linux-2.6.git/arch/x86/boot/main.c
=====================================================================
@@ -131,7 +131,7 @@ void main(void)
 	copy_boot_params();
 
 	/* Initialize the early-boot console */
-	console_init();
+	console_init(&boot_params);
 
 	/* End of heap check */
 	init_heap();

arch/x86/boot/tty.c +14 ~~-37~~

95 lines not on this page · raw message

arch/x86/boot/tty.h new file +45 -0

45 lines not on this page · raw message

arch/x86/include/asm/bootparam.h +1 -1

Index: linux-2.6.git/arch/x86/include/asm/bootparam.h
=====================================================================
@@ -93,7 +93,7 @@ struct efi_info {
 struct boot_params {
 	struct screen_info screen_info;			/* 0x000 */
 	struct apm_bios_info apm_bios_info;		/* 0x040 */
-	__u8  _pad2[4];					/* 0x054 */
+	__u32 early_serial_base;			/* 0x054 */
 	__u64  tboot_addr;				/* 0x058 */
 	struct ist_info ist_info;			/* 0x060 */
 	__u8  _pad3[16];				/* 0x070 */

arch/x86/kernel/early_printk.c +5 ~~-31~~

Index: linux-2.6.git/arch/x86/kernel/early_printk.c
=====================================================================
@@ -17,6 +17,8 @@
 #include <asm/pgtable.h>
 #include <linux/usb/ehci_def.h>
 
+#include "../boot/tty.h"
+
 /* Simple VGA output */
 #define VGABASE		(__ISA_IO_base + 0xb8000)

@@ -73,46 +75,18 @@ static struct console early_vga_console 
 
 /* Serial functions loosely based on a similar package from Klaus P. Gerlicher */
 
-static int early_serial_base = 0x3f8;  /* ttyS0 */
-
-#define XMTRDY          0x20
-
-#define DLAB		0x80
-
-#define TXR             0       /*  Transmit register (WRITE) */
-#define RXR             0       /*  Receive register  (READ)  */
-#define IER             1       /*  Interrupt Enable          */
-#define IIR             2       /*  Interrupt ID              */
-#define FCR             2       /*  FIFO control              */
-#define LCR             3       /*  Line control              */
-#define MCR             4       /*  Modem control             */
-#define LSR             5       /*  Line Status               */
-#define MSR             6       /*  Modem Status              */
-#define DLL             0       /*  Divisor Latch Low         */
-#define DLH             1       /*  Divisor latch High        */
-
-static int early_serial_putc(unsigned char ch)
-{
-	unsigned timeout = 0xffff;
-
-	while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout)
-		cpu_relax();
-	outb(ch, early_serial_base + TXR);
-	return timeout ? 0 : -1;
-}
+static int early_serial_base = DEFAULT_SERIAL_PORT;
 
 static void early_serial_write(struct console *con, const char *s, unsigned n)
 {
 	while (*s && n-- > 0) {
 		if (*s == '\n')
-			early_serial_putc('\r');
-		early_serial_putc(*s);
+			__serial_putchar('\r', early_serial_base);
+		__serial_putchar(*s, early_serial_base);
 		s++;
 	}
 }
 
-#define DEFAULT_BAUD 9600
-
 static __init void early_serial_init(char *s)
 {
 	unsigned char c;

Cyrill Gorcunov

2010-08-02 17:43 UTC #23 lore raw

On Mon, Aug 02, 2010 at 02:17:31AM -0700, Yinghai Lu wrote:
...

Quoted 14 lines

Index: linux-2.6/arch/x86/boot/printf.c
===================================================================

arch/x86/boot/printf.c +1 -1

@@ -34,7 +34,7 @@ static int skip_atoi(const char **s)
 #define SMALL	32		/* Must be 32 == 0x20 */
 #define SPECIAL	64		/* 0x */
 
-#define do_div(n,base) ({ \
+#define __do_div(n, base) ({ \
 int __res; \
 __res = ((unsigned long) n) % (unsigned) base; \
 n = ((unsigned long) n) / (unsigned) base; \

arch/x86/boot/printf.c static char *number(char *str, long num, · line 86

Quoted 5 lines

arch/x86/boot/printf.c +1 -1

@@ -83,7 +83,7 @@ static char *number(char *str, long num,
 		tmp[i++] = '0';
 	else
 		while (num != 0)
-			tmp[i++] = (digits[do_div(num, base)] | locase);
+			tmp[i++] = (digits[__do_div(num, base)] | locase);

Yinghai, what was wrong with the origin do_div? After inclusion it as "printf.c" in another *.c do_div gets clashed?

-- Cyrill

Cyrill Gorcunov

2010-08-02 17:49 UTC #6 lore raw

Re: [PATCH -v3 2/2] x86: more early console output from compressed/misc.c

Quoted 14 lines · Yinghai Lu

will get
|Decompressing Linux... Parsing ELF... done.
|Booting the kernel.
in serial console.
reuse code from arch/x86/boot/
and we can use printf if needed
(quoted diff) +0 -2
-v2: define BOOT_BOOT_H to avoid include boot.h
-v3: early_serial_base need to be static in misc.c ?

Quoted 7 lines

Signed-off-by Yinghai Lu <[email protected]>

---
 arch/x86/boot/compressed/misc.c |   65 +++++++++++++++++++++++++++++++++++++++-
 arch/x86/boot/main.c            |    6 +--
 2 files changed, 66 insertions(+), 5 deletions(-)

It seems eventually we just add ~80 lines of code in compare with what we had before, just to print "Decompressing..." by serial line. Not sure Yinghai if it worth it. Though having printf that early might be quite useful for those who debugging or developing new compressors/decompressors. If it would be small non-intrusive patch I would both hands for it but now I simply don't know (to be fair mine proposal based on your initial patch not better either ;)

-- Cyrill

Thiago Farina

2010-08-02 17:56 UTC #38 lore raw

In reply to Thiago Farina

Quoted 15 lines · Yinghai Lu

Index: linux-2.6/arch/x86/boot/string.c
===================================================================
arch/x86/boot/string.c +6 -1
@@ -12,7 +12,21 @@
  * Very basic string functions
  */
 
-#include "boot.h"
+static inline int isdigit(int ch)
+{
+       return (ch >= '0') && (ch <= '9');
+}
+
+static inline int isxdigit(int ch)

arch/x86/boot/string.c line 30

Quoted 10 lines

arch/x86/boot/string.c +9 -0

+{
+       if (isdigit(ch))
+               return true;
+
+       if ((ch >= 'a') && (ch <= 'f'))
+               return true;
+
+       return (ch >= 'A') && (ch <= 'F');
+}

These to functions above can be fairly simplified by writting as:

static bool inline is_hex_digit(int c) {
return (c >= '0' && c <= '9') ||

            (c >= 'A' && c <= 'F') ||
            (c >= 'a' && c <= 'f');
}

Thanks.

Thiago Farina

2010-08-02 18:00 UTC #39 lore raw

Quoted 29 lines · Thiago Farina

Quoted 15 lines · Yinghai Lu
Index: linux-2.6/arch/x86/boot/string.c
===================================================================
arch/x86/boot/string.c +6 -1
@@ -12,7 +12,21 @@
  * Very basic string functions
  */
 
-#include "boot.h"
+static inline int isdigit(int ch)
+{
+       return (ch >= '0') && (ch <= '9');
+}
+
+static inline int isxdigit(int ch)
arch/x86/boot/string.c line 30
Quoted 10 lines
arch/x86/boot/string.c +9 -0
+{
+       if (isdigit(ch))
+               return true;
+
+       if ((ch >= 'a') && (ch <= 'f'))
+               return true;
+
+       return (ch >= 'A') && (ch <= 'F');
+}
 
These to functions above can be fairly simplified by writting as:

Quoted 6 lines

static bool inline is_hex_digit(int c) {
return (c >= '0' && c <= '9') ||
(c >= 'A' && c <= 'F') ||
(c >= 'a' && c <= 'f');
}

Wow, sorry, this should be:

static inline bool is_hex_digit(int c) { ... }

H. Peter Anvin

reviewer

2010-08-02 18:28 UTC #40 lore raw

Quoted 9 lines · Thiago Farina

These to functions above can be fairly simplified by writting as:
static bool inline is_hex_digit(int c) {
return (c >= '0' && c <= '9') ||
            (c >= 'A' && c <= 'F') ||
            (c >= 'a' && c <= 'f');
}

a) You lose the isdigit() functionality, which is useful on its own.
b) Does this enahance readability in any way?
c) Your proposed renaming is nonstandard.

As such, I don't think this is a good idea.

-hpa

H. Peter Anvin

reviewer

2010-08-02 18:40 UTC #7 lore raw

Re: [PATCH -v3 2/2] x86: more early console output from compressed/misc.c

Quoted 17 lines · Cyrill Gorcunov

Quoted 16 lines · Yinghai Lu
will get
|Decompressing Linux... Parsing ELF... done.
|Booting the kernel.
in serial console.
reuse code from arch/x86/boot/
and we can use printf if needed
(quoted diff) +0 -2
-v2: define BOOT_BOOT_H to avoid include boot.h
-v3: early_serial_base need to be static in misc.c ?
Signed-off-by Yinghai Lu <[email protected]>

Quoted 13 lines

Quoted 5 lines
---
 arch/x86/boot/compressed/misc.c |   65 +++++++++++++++++++++++++++++++++++++++-
 arch/x86/boot/main.c            |    6 +--
 2 files changed, 66 insertions(+), 5 deletions(-)
It seems eventually we just add ~80 lines of code in compare with what we had before, just to print "Decompressing..." by serial line. Not sure Yinghai if it worth it. Though having printf that early might be quite useful for those who debugging or developing new compressors/decompressors. If it would be small non-intrusive patch I would both hands for it but now I simply don't know (to be fair mine proposal based on your initial patch not better either ;)

Decompressing... is one thing, and if it was only that, I'd just suggest killing off the console I/O in boot/compressed. Getting an error message out when there is a decompression failure is another thing.

Processing the command line a novo is somewhat painful, but it does deal better with bootloaders that use the 32-bit entry point by necessity (kexec, EFI) or due to sheer stupidity (Grub2).

As such, I think it's a worthwhile addition, as long as the source code can be cleanly shared with the boot/ directory.

-hpa

Cyrill Gorcunov

2010-08-02 18:54 UTC #8 lore raw

Re: [PATCH -v3 2/2] x86: more early console output from compressed/misc.c

Quoted 13 lines · H. Peter Anvin

Quoted 12 lines · Cyrill Gorcunov
Quoted 11 lines · Yinghai Lu
will get
|Decompressing Linux... Parsing ELF... done.
|Booting the kernel.
in serial console.
reuse code from arch/x86/boot/
and we can use printf if needed

...

Quoted 13 lines

Quoted 8 lines
It seems eventually we just add ~80 lines of code in compare with what we had before, just to print "Decompressing..." by serial line. Not sure Yinghai if it worth it. Though having printf that early might be quite useful for those who debugging or developing new compressors/decompressors. If it would be small non-intrusive patch I would both hands for it but now I simply don't know (to be fair mine proposal based on your initial patch not better either ;)
Decompressing... is one thing, and if it was only that, I'd just suggest killing off the console I/O in boot/compressed. Getting an error message out when there is a decompression failure is another thing.

Quoted 9 lines

Processing the command line a novo is somewhat painful, but it does deal better with bootloaders that use the 32-bit entry point by necessity (kexec, EFI) or due to sheer stupidity (Grub2).
As such, I think it's a worthwhile addition, as long as the source code can be cleanly shared with the boot/ directory.
-hpa

ok, fair enough, I just don't like nesting *.c inclusion you know but seems it would be the only more-less clean way here.

-- Cyrill

H. Peter Anvin

reviewer

2010-08-02 18:59 UTC #9 lore raw

Re: [PATCH -v3 2/2] x86: more early console output from compressed/misc.c

Quoted 4 lines · Cyrill Gorcunov

ok, fair enough, I just don't like nesting *.c inclusion you know but seems it would be the only more-less clean way here.

I don't mind it *as long as* the including file contains nothing but a single #include statement -- which is just another way to say "the same thing as this other file". Don't combine files.

Look at most of the .c files in arch/x86/kernel/acpi/realmode/ for an example.

-hpa

Thiago Farina

2010-08-02 19:09 UTC #41 lore raw

Quoted 11 lines · H. Peter Anvin

Quoted 9 lines · Thiago Farina
These to functions above can be fairly simplified by writting as:
static bool inline is_hex_digit(int c) {
return (c >= '0' && c <= '9') ||
(c >= 'A' && c <= 'F') ||
(c >= 'a' && c <= 'f');
}

Quoted 4 lines

a) You lose the isdigit() functionality, which is useful on its own.
b) Does this enahance readability in any way?
c) Your proposed renaming is nonstandard.

What about this instead?

static inline bool isxdigit(int ch) {
return (isdigit(ch) || (ch >= 'A' && ch <= 'F') || (ch >= 'a' && ch <= 'f');
}

Quoted 4 lines

As such, I don't think this is a good idea.
-hpa

Yinghai Lu

author

2010-08-02 19:17 UTC #24 lore raw

Quoted 10 lines · Cyrill Gorcunov

On Mon, Aug 02, 2010 at 02:17:31AM -0700, Yinghai Lu wrote:
...
Quoted 8 lines
Index: linux-2.6/arch/x86/boot/printf.c
===================================================================
arch/x86/boot/printf.c +0 -0
@@ -34,7 +34,7 @@ static int skip_atoi(const char **s)
 #define SMALL	32		/* Must be 32 == 0x20 */
 #define SPECIAL	64		/* 0x */
 

Quoted 14 lines

arch/x86/boot/printf.c static char *number(char *str, long num, · line 86
Quoted 11 lines
arch/x86/boot/printf.c +2 -2
-#define do_div(n,base) ({ \
+#define __do_div(n, base) ({ \
 int __res; \
 __res = ((unsigned long) n) % (unsigned) base; \
 n = ((unsigned long) n) / (unsigned) base; \
@@ -83,7 +83,7 @@ static char *number(char *str, long num,
 		tmp[i++] = '0';
 	else
 		while (num != 0)
-			tmp[i++] = (digits[do_div(num, base)] | locase);
+			tmp[i++] = (digits[__do_div(num, base)] | locase);
Yinghai, what was wrong with the origin do_div? After inclusion it as "printf.c" in another *.c do_div gets clashed?

yes. get clashed if include that printf.c in arch/x86/boot/compressed/misc.c

Yinghai

Yinghai Lu

author

2010-08-02 19:24 UTC #29 lore raw

Quoted 11 lines · Cyrill Gorcunov

Quoted 9 lines · Yinghai Lu
Seperate early_console_setup from tty.c
also make main.c to include printf.c/string.c/cmdline.c
will reuse early_serial_console.c/string.c/printf.c/cmdline.c in compressed/misc.c
Signed-off-by Yinghai Lu <[email protected]>
---

Quoted 8 lines

Hi Yinghai, I'll try to find some time for review though it looks somehow too 'big' for me :)
Actually by reading your initial approach (which was much smaller in size) I thought we end up in something like the patch below, though I'll review this seris. So just to share (I've tested it under qemu). The idea is the same as your was, so I pushed all constant parts into header and use it when needed passing serial line base port via boot_params.

Eric doesn't like early_serial_console_base in zero page. and said that is fragile.

So try to include string.c/printf.c/cmdline.c/early_serial_console.c in arch/x86/boot/compressed/misc.c and analyze that command line again.

then kexec path will get support too. that is from arch/x86/boot/compressed/head_32.S or head_64.S, startup_32. and skip arch/x86/boot/main.c

later with following patch for 3, we get all covered in c code.
1. arch/x86/boot/main.c: setup code.
2. arch/x86/boot/compressed/misc.c: decompress_kernel code : the 2 -v3 patches that i sent last night.
3. arch/x86/kernel/head64.c: real kernel.

maybe we can make early_serial_console.c and early_printk.c to share some .h etc later.

Thanks

Yinghai

[PATCH -v2] x86: Setup early console as early as possible

Analyze "console=uart8250,io,0x3f8,115200n8" in i386_start_kernel/x86_64_start_kernel, and call setup_early_serial8250_console() to init early serial console.

only can handle io port kind of 8250. because mmio need ioremap.

-v2: use boot_params.hdr.version instead of adding another variable, Suggested by hpa
update after using x86 memblock patchset

Signed-off-by Yinghai Lu <[email protected]>

---
 arch/x86/include/asm/setup.h |    2 ++
 arch/x86/kernel/head.c       |   27 +++++++++++++++++++++++++++
 arch/x86/kernel/head32.c     |    2 ++
 arch/x86/kernel/head64.c     |   13 +++++++++++--
 kernel/printk.c              |    4 ++++
 5 files changed, 46 insertions(+), 2 deletions(-)

arch/x86/include/asm/setup.h +2 -0

Index: linux-2.6/arch/x86/include/asm/setup.h
===================================================================
@@ -42,6 +42,8 @@ static inline void visws_early_detect(vo
 #endif
 
 extern unsigned long saved_video_mode;
+int setup_early_serial8250_console(char *cmdline);
+void setup_early_console(void);
 
 extern void reserve_standard_io_resources(void);
 extern void i386_reserve_resources(void);

arch/x86/kernel/head.c +27 -0

Index: linux-2.6/arch/x86/kernel/head.c
===================================================================
@@ -54,3 +54,30 @@ void __init reserve_ebda_region(void)
 	/* reserve all memory between lowmem and the 1MB mark */
 	memblock_x86_reserve_range(lowmem, 0x100000, "* BIOS reserved");
 }
+
+
+void __init setup_early_console(void)
+{
+#ifdef CONFIG_SERIAL_8250_CONSOLE
+	char constr[64], *p, *q;
+
+	/* Can not handle mmio type 8250 uart yet, too early */
+	p = strstr(boot_command_line, "console=uart8250,io,");
+	if (!p)
+		p = strstr(boot_command_line, "console=uart,io,");
+	if (!p)
+		return;
+
+	p += 8;	/* sizeof "console=" */
+	q = strchr(p, ' ');
+	if ((q - p) >= sizeof(constr))
+		return;
+
+	memset(constr, 0, sizeof(constr));
+	memcpy(constr, p, q - p);
+
+	lockdep_init();
+
+	setup_early_serial8250_console(constr);
+#endif
+}

arch/x86/kernel/head32.c +2 -0

Index: linux-2.6/arch/x86/kernel/head32.c
===================================================================
@@ -31,6 +31,8 @@ static void __init i386_default_early_se
 
 void __init i386_start_kernel(void)
 {
+	setup_early_console();
+
 	memblock_init();
 
 #ifdef CONFIG_X86_TRAMPOLINE

arch/x86/kernel/head64.c +11 -2

Index: linux-2.6/arch/x86/kernel/head64.c
===================================================================
@@ -46,6 +46,10 @@ static void __init copy_bootdata(char *r
 {
 	char * command_line;
 
+	/* make sure if it is copied already */
+	if (boot_params.hdr.version)
+		return;
+
 	memcpy(&boot_params, real_mode_data, sizeof boot_params);
 	if (boot_params.hdr.cmd_line_ptr) {
 		command_line = __va(boot_params.hdr.cmd_line_ptr);

@@ -74,6 +78,10 @@ void __init x86_64_start_kernel(char * r
 	/* clear bss before set_intr_gate with early_idt_handler */
 	clear_bss();
 
+	/* boot_params is in bss */
+	copy_bootdata(__va(real_mode_data));
+	setup_early_console();
+
 	/* Make NULL pointers segfault */
 	zap_identity_mappings();

@@ -97,9 +105,10 @@ void __init x86_64_start_kernel(char * r
 
 void __init x86_64_start_reservations(char *real_mode_data)
 {
-	memblock_init();
-
 	copy_bootdata(__va(real_mode_data));
+	setup_early_console();
+
+	memblock_init();
 
 	memblock_x86_reserve_range(__pa_symbol(&_text), __pa_symbol(&__bss_stop), "TEXT DATA BSS");

kernel/printk.c +4 -0

Index: linux-2.6/kernel/printk.c
===================================================================
@@ -1204,6 +1204,10 @@ void register_console(struct console *ne
 	if (console_drivers && newcon->flags & CON_BOOT) {
 		/* find the last or real console */
 		for_each_console(bcon) {
+			/* not again */
+			if (bcon == newcon)
+				return;
+
 			if (!(bcon->flags & CON_BOOT)) {
 				printk(KERN_INFO "Too late to register bootconsole %s%d\n",
 					newcon->name, newcon->index);

Yinghai Lu

author

2010-08-02 19:37 UTC #10 lore raw

Re: [PATCH -v3 2/2] x86: more early console output from compressed/misc.c

Quoted 6 lines · H. Peter Anvin

Quoted 4 lines · Cyrill Gorcunov
ok, fair enough, I just don't like nesting *.c inclusion you know but seems it would be the only more-less clean way here.

Quoted 6 lines

I don't mind it *as long as* the including file contains nothing but a single #include statement -- which is just another way to say "the same thing as this other file". Don't combine files.
Look at most of the .c files in arch/x86/kernel/acpi/realmode/ for an example.

it seems I can not global variables in arch/x86/boot/compressed/misc.c

and misc.c already include some decompress .c like

#ifdef CONFIG_KERNEL_GZIP
#include "../../../../lib/decompress_inflate.c"
#endif

#ifdef CONFIG_KERNEL_BZIP2
#include "../../../../lib/decompress_bunzip2.c"
#endif

#ifdef CONFIG_KERNEL_LZMA
#include "../../../../lib/decompress_unlzma.c"
#endif

#ifdef CONFIG_KERNEL_LZO
#include "../../../../lib/decompress_unlzo.c"
#endif

this patch change to misc.c are following lines:

#define BOOT_BOOT_H
#include "../isdigit.h"
#include "../string.c"
#include "../printf.c"

...

static unsigned long fs;
static inline void set_fs(unsigned long seg)

{
        fs = seg << 4;  /* shift it back */
}
typedef unsigned long addr_t;
static inline char rdfs8(addr_t addr)
{
        return *((char *)(fs + addr));
}
#include "../cmdline.c"
static inline int cmdline_find_option(const char *option, char *buffer, int bufsize)
{
        return __cmdline_find_option(real_mode->hdr.cmd_line_ptr, option, buffer, bufsize);
}
static inline int cmdline_find_option_bool(const char *option)
{
        return __cmdline_find_option_bool(real_mode->hdr.cmd_line_ptr, option);
}

static int early_serial_base;
#include "../early_serial_console.c"

or put them in another file?

Thanks

Yinghai

Cyrill Gorcunov

2010-08-02 20:18 UTC #30 lore raw

In reply to Thiago Farina

Quoted 15 lines · Yinghai Lu

Quoted 14 lines · Cyrill Gorcunov
Quoted 9 lines · Yinghai Lu
Seperate early_console_setup from tty.c
also make main.c to include printf.c/string.c/cmdline.c
will reuse early_serial_console.c/string.c/printf.c/cmdline.c in compressed/misc.c
Signed-off-by Yinghai Lu <[email protected]>
---
Hi Yinghai, I'll try to find some time for review though it looks somehow too 'big' for me :)

Quoted 8 lines

Quoted 5 lines
Actually by reading your initial approach (which was much smaller in size) I thought we end up in something like the patch below, though I'll review this seris. So just to share (I've tested it under qemu). The idea is the same as your was, so I pushed all constant parts into header and use it when needed passing serial line base port via boot_params.
Eric doesn't like early_serial_console_base in zero page. and said that is fragile.

yeah, and Peter noted too as well, I missed Eric's mail in first place.

Quoted 6 lines

So try to include string.c/printf.c/cmdline.c/early_serial_console.c in arch/x86/boot/compressed/misc.c and analyze that command line again.
then kexec path will get support too. that is from arch/x86/boot/compressed/head_32.S or head_64.S, startup_32. and skip arch/x86/boot/main.c

Quoted 7 lines

later with following patch for 3, we get all covered in c code.
1. arch/x86/boot/main.c: setup code.
2. arch/x86/boot/compressed/misc.c: decompress_kernel code : the 2 -v3 patches that i sent last night.
3. arch/x86/kernel/head64.c: real kernel.
maybe we can make early_serial_console.c and early_printk.c to share some .h etc later.

yes, sounds tempting for me ;)

Quoted 16 lines

Thanks
Yinghai
[PATCH -v2] x86: Setup early console as early as possible
Analyze "console=uart8250,io,0x3f8,115200n8" in i386_start_kernel/x86_64_start_kernel, and call setup_early_serial8250_console() to init early serial console.
only can handle io port kind of 8250. because mmio need ioremap.
-v2: use boot_params.hdr.version instead of adding another variable, Suggested by hpa
update after using x86 memblock patchset
Signed-off-by Yinghai Lu <[email protected]>
---

...

arch/x86/kernel/head.c void __init reserve_ebda_region(void) · line 75

Quoted 6 lines

arch/x86/kernel/head.c +6 -0

+
+	p += 8;	/* sizeof "console=" */
+	q = strchr(p, ' ');
+	if ((q - p) >= sizeof(constr))
+		return;
+

I think the better would be to explicitly point q=0 here, ie if (!q || ...) (yes, it'll trigger with former too but anyway this would be somewhat cleaner)

Quoted 8 lines

arch/x86/kernel/head.c +8 -0

+	memset(constr, 0, sizeof(constr));
+	memcpy(constr, p, q - p);
+
+	lockdep_init();
+
+	setup_early_serial8250_console(constr);
+#endif
+}

...

arch/x86/kernel/head64.c static void __init copy_bootdata(char *r · line 52

Quoted 4 lines

arch/x86/kernel/head64.c +4 -0

+	/* make sure if it is copied already */
+	if (boot_params.hdr.version)
+		return;
+

And Yinghai, lets be more verbose here a bit, since for those who will be reading this code later might be non-obvious why we have checked for 'version' here. I guess something like "an easy way to check if boot_params were already copied". Actually it's clean from commit message but I think we first read code comments and commit messages after, agreed? ;-)

arch/x86/kernel/head64.c void __init x86_64_start_kernel(char * r · line 80

Quoted 7 lines

arch/x86/kernel/head64.c +0 -0

 	memcpy(&boot_params, real_mode_data, sizeof boot_params);
 	if (boot_params.hdr.cmd_line_ptr) {
 		command_line = __va(boot_params.hdr.cmd_line_ptr);

@@ -74,6 +78,10 @@ void __init x86_64_start_kernel(char * r
 	/* clear bss before set_intr_gate with early_idt_handler */
 	clear_bss();

...

Other then that looks good for me, thanks! My Reviewed-by if needed.

-- Cyrill

Yinghai Lu

author

2010-08-02 20:31 UTC #31 lore raw

Quoted 30 lines · Cyrill Gorcunov

Quoted 26 lines · Yinghai Lu
Quoted 1 line · Cyrill Gorcunov
On Mon, Aug 02, 2010 at 12:13:31AM -0700, Yinghai Lu wrote:
So try to include string.c/printf.c/cmdline.c/early_serial_console.c in arch/x86/boot/compressed/misc.c and analyze that command line again.
then kexec path will get support too. that is from arch/x86/boot/compressed/head_32.S or head_64.S, startup_32. and skip arch/x86/boot/main.c
later with following patch for 3, we get all covered in c code.
1. arch/x86/boot/main.c: setup code.
2. arch/x86/boot/compressed/misc.c: decompress_kernel code : the 2 -v3 patches that i sent last night.
3. arch/x86/kernel/head64.c: real kernel.
[PATCH -v2] x86: Setup early console as early as possible
Analyze "console=uart8250,io,0x3f8,115200n8" in i386_start_kernel/x86_64_start_kernel, and call setup_early_serial8250_console() to init early serial console.
only can handle io port kind of 8250. because mmio need ioremap.
-v2: use boot_params.hdr.version instead of adding another variable, Suggested by hpa
update after using x86 memblock patchset
Signed-off-by Yinghai Lu <[email protected]>
---
...

Quoted 10 lines

arch/x86/kernel/head64.c static void __init copy_bootdata(char *r · line 52
Quoted 4 lines
arch/x86/kernel/head64.c +4 -0
+	/* make sure if it is copied already */
+	if (boot_params.hdr.version)
+		return;
+
And Yinghai, lets be more verbose here a bit, since for those who will be reading this code later might be non-obvious why we have checked for 'version' here. I guess something like "an easy way to check if boot_params were already copied". Actually it's clean from commit message but I think we first read code comments and commit messages after, agreed? ;-)

will change to

/*
* hdr.version is always not 0, so check it to see
* if boot_params is copied or not.
*/

will resend this patch after memblock x86 changes.

H. Peter Anvin

reviewer

2010-08-02 20:34 UTC #42 lore raw

Quoted 17 lines · Thiago Farina

Quoted 11 lines · H. Peter Anvin
Quoted 9 lines · Thiago Farina
These to functions above can be fairly simplified by writting as:
static bool inline is_hex_digit(int c) {
return (c >= '0' && c <= '9') ||
            (c >= 'A' && c <= 'F') ||
            (c >= 'a' && c <= 'f');
}
Quoted 4 lines
a) You lose the isdigit() functionality, which is useful on its own.
b) Does this enahance readability in any way?
c) Your proposed renaming is nonstandard.

Quoted 8 lines

What about this instead?
static inline bool isxdigit(int ch) {
return (isdigit(ch) || (ch >= 'A' && ch <= 'F') || (ch >= 'a' && ch <= 'f');
}
Quoted 2 lines
As such, I don't think this is a good idea.

Again, I don't think it adds any readability; the compiler will produce the same code.

-hpa

Cyrill Gorcunov

2010-08-02 20:37 UTC #32 lore raw

On Mon, Aug 02, 2010 at 01:30:17PM -0700, Yinghai Lu wrote:
...

Quoted 13 lines

Quoted 10 lines
arch/x86/kernel/head64.c static void __init copy_bootdata(char *r · line 52
Quoted 4 lines
arch/x86/kernel/head64.c +4 -0
+	/* make sure if it is copied already */
+	if (boot_params.hdr.version)
+		return;
+
And Yinghai, lets be more verbose here a bit, since for those who will be reading this code later might be non-obvious why we have checked for 'version' here. I guess something like "an easy way to check if boot_params were already copied". Actually it's clean from commit message but I think we first read code comments and commit messages after, agreed? ;-)
will change to

Quoted 9 lines

/*
* hdr.version is always not 0, so check it to see
* if boot_params is copied or not.
*/
will resend this patch after memblock x86 changes.
YH

ok, thanks!

-- Cyrill

H. Peter Anvin

reviewer

2010-08-02 20:39 UTC #11 lore raw

Re: [PATCH -v3 2/2] x86: more early console output from compressed/misc.c

Quoted 3 lines · Yinghai Lu

it seems I can not global variables in arch/x86/boot/compressed/misc.c

Well, that should be fixed, then. If we can't use the linker for what it's supposed to be used for it's just crap.

Quoted 10 lines

and misc.c already include some decompress .c like
#ifdef CONFIG_KERNEL_GZIP
#include "../../../../lib/decompress_inflate.c"
#endif
#ifdef CONFIG_KERNEL_BZIP2
#include "../../../../lib/decompress_bunzip2.c"
#endif

Quoted 8 lines

#ifdef CONFIG_KERNEL_LZMA
#include "../../../../lib/decompress_unlzma.c"
#endif
#ifdef CONFIG_KERNEL_LZO
#include "../../../../lib/decompress_unlzo.c"
#endif

Yes, I know; that's crap in a lot of ways too... the whole decompression stuff is its own issue which is slowly being addressed. It's not an excuse to make the code crappier than it already is.

Quoted 29 lines

this patch change to misc.c are following lines:

#define BOOT_BOOT_H
#include "../isdigit.h"
#include "../string.c"
#include "../printf.c"

...

static unsigned long fs;
static inline void set_fs(unsigned long seg)

{
        fs = seg << 4;  /* shift it back */
}
typedef unsigned long addr_t;
static inline char rdfs8(addr_t addr)
{
        return *((char *)(fs + addr));
}
#include "../cmdline.c"
static inline int cmdline_find_option(const char *option, char *buffer, int bufsize)
{
        return __cmdline_find_option(real_mode->hdr.cmd_line_ptr, option, buffer, bufsize);
}
static inline int cmdline_find_option_bool(const char *option)
{
        return __cmdline_find_option_bool(real_mode->hdr.cmd_line_ptr, option);
}

Quoted 5 lines

static int early_serial_base;
#include "../early_serial_console.c"
or put them in another file?

Hmf... games with set_fs() aren't a whole lot of fun at all. I think it would be better to define some wrappers specific to cmdline.c which allow it to be using a real pointer in 32-bit mode.

I'll see if I can muck with it, it shouldn't take long.

-hpa

H. Peter Anvin

reviewer

2010-08-02 21:00 UTC #12 lore raw

Re: [PATCH -v3 2/2] x86: more early console output from compressed/misc.c

Quoted 3 lines · Yinghai Lu

it seems I can not global variables in arch/x86/boot/compressed/misc.c

I just looked at it, it's the fact that we don't relocate the GOT that is causing problems. It's relatively easy to fix: here is a patch, but in grand Linus tradition it is completely untested.

-hpa

arch/x86/boot/compressed/head_32.S +13 -0

index f543b70..6597aeb 100644
@@ -124,6 +124,19 @@ relocated:
 	rep	stosl
 
 /*
+ * Adjust our own GOT
+ */
+	leal	_got(%ebx), %esi
+	leal	_egot(%ebx), %edi
+1:
+	cmpl	%esi, %edi
+	jae	2f
+	addl	%ebx, (%esi)
+	addl	$4, %esi
+	jmp	1b
+2:
+
+/*
  * Do the decompression, and jump to the new kernel..
  */
 	leal	z_extract_offset_negative(%ebx), %ebp

arch/x86/boot/compressed/head_64.S +13 -0

index faff0dc..ef69e97 100644
@@ -280,6 +280,19 @@ relocated:
 	rep	stosq
 
 /*
+ * Adjust our own GOT
+ */
+	leaq	_got(%rip), %rsi
+	leaq	_egot(%rip), %rdi
+1:
+	cmpq	%rsi, %rdi
+	jae	2f
+	addq	%rbx, (%rsi)
+	addq	$8, %rsi
+	jmp	1b
+2:
+	
+/*
  * Do the decompression, and jump to the new kernel..
  */
 	pushq	%rsi			/* Save the real mode argument */

arch/x86/boot/compressed/vmlinux.lds.S +6 -0

index 5ddabce..34d047c 100644
@@ -41,6 +41,12 @@ SECTIONS
 		*(.rodata.*)
 		_erodata = . ;
 	}
+	.got : {
+		_got = .;
+		KEEP(*(.got.plt))
+		KEEP(*(.got))
+		_egot = .;
+	}
 	.data :	{
 		_data = . ;
 		*(.data)

H. Peter Anvin

reviewer

2010-08-02 21:09 UTC #13 lore raw

Re: [PATCH -v3 2/2] x86: more early console output from compressed/misc.c

Quoted 9 lines · H. Peter Anvin

Quoted 3 lines · Yinghai Lu
it seems I can not global variables in arch/x86/boot/compressed/misc.c
I just looked at it, it's the fact that we don't relocate the GOT that is causing problems. It's relatively easy to fix: here is a patch, but in grand Linus tradition it is completely untested.

Untested indeed... here is one which doesn't clobber live registers.

-hpa

arch/x86/boot/compressed/head_32.S +13 -0

index f543b70..58a8fb5 100644
@@ -124,6 +124,19 @@ relocated:
 	rep	stosl
 
 /*
+ * Adjust our own GOT
+ */
+	leal	_got(%ebx), %edx
+	leal	_egot(%ebx), %ecx
+1:
+	cmpl	%edx, %ecx
+	jae	2f
+	addl	%ebx, (%edx)
+	addl	$4, %edx
+	jmp	1b
+2:
+
+/*
  * Do the decompression, and jump to the new kernel..
  */
 	leal	z_extract_offset_negative(%ebx), %ebp

arch/x86/boot/compressed/head_64.S +13 -0

index faff0dc..892db2d 100644
@@ -280,6 +280,19 @@ relocated:
 	rep	stosq
 
 /*
+ * Adjust our own GOT
+ */
+	leaq	_got(%rip), %rdx
+	leaq	_egot(%rip), %rcx
+1:
+	cmpq	%rdx, %rcx
+	jae	2f
+	addq	%rbx, (%rdx)
+	addq	$8, %rdx
+	jmp	1b
+2:
+	
+/*
  * Do the decompression, and jump to the new kernel..
  */
 	pushq	%rsi			/* Save the real mode argument */

arch/x86/boot/compressed/vmlinux.lds.S +6 -0

index 5ddabce..34d047c 100644
@@ -41,6 +41,12 @@ SECTIONS
 		*(.rodata.*)
 		_erodata = . ;
 	}
+	.got : {
+		_got = .;
+		KEEP(*(.got.plt))
+		KEEP(*(.got))
+		_egot = .;
+	}
 	.data :	{
 		_data = . ;
 		*(.data)

Yinghai Lu

author

2010-08-02 21:25 UTC #14 lore raw

Re: [PATCH -v3 2/2] x86: more early console output from compressed/misc.c

Quoted 6 lines · H. Peter Anvin

Quoted 5 lines · H. Peter Anvin
Quoted 3 lines · Yinghai Lu
it seems I can not global variables in arch/x86/boot/compressed/misc.c

Quoted 9 lines

Quoted 4 lines
I just looked at it, it's the fact that we don't relocate the GOT that is causing problems. It's relatively easy to fix: here is a patch, but in grand Linus tradition it is completely untested.
Untested indeed... here is one which doesn't clobber live registers.
-hpa

still doesn't work.

with global early_serial_base got :

early console in setup code

[    0.000000] bootconsole [uart0] enabled

with static early_serial_base got :

early console in setup code
early console in decompress_kernel
decompress_kernel:
input: [0x24a0269-0x2e8b234], output: 0x1000000, heap: [0x2e909c0-0x2e979bf]

Decompressing Linux... Parsing ELF... done.
Booting the kernel.

[    0.000000] bootconsole [uart0] enabled

Thanks

Yinghai

H. Peter Anvin

reviewer

2010-08-02 21:28 UTC #15 lore raw

Re: [PATCH -v3 2/2] x86: more early console output from compressed/misc.c

Quoted 6 lines · H. Peter Anvin

Quoted 5 lines · H. Peter Anvin
Quoted 3 lines · Yinghai Lu
it seems I can not global variables in arch/x86/boot/compressed/misc.c

Quoted 7 lines

Quoted 4 lines
I just looked at it, it's the fact that we don't relocate the GOT that is causing problems. It's relatively easy to fix: here is a patch, but in grand Linus tradition it is completely untested.
Untested indeed... here is one which doesn't clobber live registers.

And of course I got the test backwards... in AT&T syntax, number compares you!

-hpa

arch/x86/boot/compressed/head_32.S +13 -0

index f543b70..67a655a 100644
@@ -124,6 +124,19 @@ relocated:
 	rep	stosl
 
 /*
+ * Adjust our own GOT
+ */
+	leal	_got(%ebx), %edx
+	leal	_egot(%ebx), %ecx
+1:
+	cmpl	%ecx, %edx
+	jae	2f
+	addl	%ebx, (%edx)
+	addl	$4, %edx
+	jmp	1b
+2:
+
+/*
  * Do the decompression, and jump to the new kernel..
  */
 	leal	z_extract_offset_negative(%ebx), %ebp

arch/x86/boot/compressed/head_64.S +13 -0

index faff0dc..52f85a1 100644
@@ -280,6 +280,19 @@ relocated:
 	rep	stosq
 
 /*
+ * Adjust our own GOT
+ */
+	leaq	_got(%rip), %rdx
+	leaq	_egot(%rip), %rcx
+1:
+	cmpq	%rcx, %rdx
+	jae	2f
+	addq	%rbx, (%rdx)
+	addq	$8, %rdx
+	jmp	1b
+2:
+	
+/*
  * Do the decompression, and jump to the new kernel..
  */
 	pushq	%rsi			/* Save the real mode argument */

arch/x86/boot/compressed/vmlinux.lds.S +6 -0

index 5ddabce..34d047c 100644
@@ -41,6 +41,12 @@ SECTIONS
 		*(.rodata.*)
 		_erodata = . ;
 	}
+	.got : {
+		_got = .;
+		KEEP(*(.got.plt))
+		KEEP(*(.got))
+		_egot = .;
+	}
 	.data :	{
 		_data = . ;
 		*(.data)

Yinghai Lu

author

2010-08-02 21:37 UTC #16 lore raw

Re: [PATCH -v3 2/2] x86: more early console output from compressed/misc.c

Quoted 12 lines · H. Peter Anvin

Quoted 11 lines · H. Peter Anvin
Quoted 9 lines · H. Peter Anvin
Quoted 3 lines · Yinghai Lu
it seems I can not global variables in arch/x86/boot/compressed/misc.c
I just looked at it, it's the fact that we don't relocate the GOT that is causing problems. It's relatively easy to fix: here is a patch, but in grand Linus tradition it is completely untested.

Quoted 6 lines

Quoted 2 lines
Untested indeed... here is one which doesn't clobber live registers.
And of course I got the test backwards... in AT&T syntax, number compares you!

great, this one works.

will have updated

[PATCH -v4 2/2] x86: more early console output from compressed/misc.c

Thanks

Yinghai

Yinghai Lu

author

2010-08-02 22:32 UTC #17 lore raw

Re: [PATCH -v3 2/2] x86: more early console output from compressed/misc.c

Quoted 12 lines · H. Peter Anvin

Quoted 11 lines · H. Peter Anvin
Quoted 9 lines · H. Peter Anvin
Quoted 3 lines · Yinghai Lu
it seems I can not global variables in arch/x86/boot/compressed/misc.c
I just looked at it, it's the fact that we don't relocate the GOT that is causing problems. It's relatively easy to fix: here is a patch, but in grand Linus tradition it is completely untested.

Quoted 5 lines

Quoted 2 lines
Untested indeed... here is one which doesn't clobber live registers.
And of course I got the test backwards... in AT&T syntax, number compares you!

updated version

Subject: [PATCH -v4 2/2] x86: more early console output from compressed/misc.c

will get

|Decompressing Linux... Parsing ELF... done.
|Booting the kernel.

in serial console.

reuse code from arch/x86/boot/
and we can use printf if needed

-v2: define BOOT_BOOT_H to avoid include boot.h
-v3: early_serial_base need to be static in misc.c ?
-v4: create seperate string.c printf.c cmdline.c early_serial_console.c
after hpa's patch that allow global variables in compressed/misc stage

Signed-off-by Yinghai Lu <[email protected]>

---
 arch/x86/boot/compressed/Makefile               |    4 -
 arch/x86/boot/compressed/cmdline.c              |   21 +++++++
 arch/x86/boot/compressed/early_serial_console.c |    4 +
 arch/x86/boot/compressed/misc.c                 |   66 +++++++++++++++---------
 arch/x86/boot/compressed/misc.h                 |   38 +++++++++++++
 arch/x86/boot/compressed/printf.c               |    4 +
 arch/x86/boot/compressed/string.c               |    4 +
 arch/x86/boot/main.c                            |    6 --
 8 files changed, 118 insertions(+), 29 deletions(-)

arch/x86/boot/compressed/misc.c +43 ~~-23~~

Index: linux-2.6/arch/x86/boot/compressed/misc.c
===================================================================
@@ -9,23 +9,7 @@
  * High loaded stuff by Hans Lermen & Werner Almesberger, Feb. 1996
  */
 
-/*
- * we have to be careful, because no indirections are allowed here, and
- * paravirt_ops is a kind of one. As it will only run in baremetal anyway,
- * we just keep it from happening
- */
-#undef CONFIG_PARAVIRT
-#ifdef CONFIG_X86_32
-#define _ASM_X86_DESC_H 1
-#endif
-
-#include <linux/linkage.h>
-#include <linux/screen_info.h>
-#include <linux/elf.h>
-#include <linux/io.h>
-#include <asm/page.h>
-#include <asm/boot.h>
-#include <asm/bootparam.h>
+#include "misc.h"
 
 /* WARNING!!
  * This code is compiled with -fPIC and it is relocated dynamically

@@ -123,15 +107,13 @@ static void error(char *m);
 /*
  * This is set up by the setup-routine at boot-time
  */
-static struct boot_params *real_mode;		/* Pointer to real-mode data */
+struct boot_params *real_mode;		/* Pointer to real-mode data */
 static int quiet;
+static int debug;
 
 void *memset(void *s, int c, size_t n);
 void *memcpy(void *dest, const void *src, size_t n);
 
-static void __putstr(int, const char *);
-#define putstr(__x)  __putstr(0, __x)
-
 #ifdef CONFIG_X86_64
 #define memptr long
 #else

@@ -170,7 +152,21 @@ static void scroll(void)
 		vidmem[i] = ' ';
 }
 
-static void __putstr(int error, const char *s)
+#define XMTRDY          0x20
+
+#define TXR             0       /*  Transmit register (WRITE) */
+#define LSR             5       /*  Line Status               */
+static void serial_putchar(int ch)
+{
+	unsigned timeout = 0xffff;
+
+	while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout)
+		cpu_relax();
+
+	outb(ch, early_serial_base + TXR);
+}
+
+void __putstr(int error, const char *s)
 {
 	int x, y, pos;
 	char c;

@@ -179,6 +175,14 @@ static void __putstr(int error, const ch
 	if (!error)
 		return;
 #endif
+	if (early_serial_base) {
+		const char *str = s;
+		while (*str) {
+			if (*str == '\n')
+				serial_putchar('\r');
+			serial_putchar(*str++);
+		}
+	}
 
 	if (real_mode->screen_info.orig_video_mode == 0 &&
 	    lines == 0 && cols == 0)

@@ -305,8 +309,10 @@ asmlinkage void decompress_kernel(void *
 {
 	real_mode = rmode;
 
-	if (real_mode->hdr.loadflags & QUIET_FLAG)
+	if (cmdline_find_option_bool("quiet"))
 		quiet = 1;
+	if (cmdline_find_option_bool("debug"))
+		debug = 1;
 
 	if (real_mode->screen_info.orig_video_mode == 7) {
 		vidmem = (char *) 0xb0000;

@@ -319,9 +325,23 @@ asmlinkage void decompress_kernel(void *
 	lines = real_mode->screen_info.orig_video_lines;
 	cols = real_mode->screen_info.orig_video_cols;
 
+	console_init();
+	if (debug)
+		putstr("early console in decompress_kernel\n");
+
 	free_mem_ptr     = heap;	/* Heap */
 	free_mem_end_ptr = heap + BOOT_HEAP_SIZE;
 
+	if (debug) {
+		putstr("decompress_kernel:\n");
+		printf("  input: [0x%lx-0x%lx], output: 0x%lx, heap: [0x%lx-0x%lx]\n",
+			 (unsigned long)input_data,
+			 (unsigned long)input_data + input_len - 1,
+			 (unsigned long)output,
+			 (unsigned long)heap,
+			 (unsigned long)heap + BOOT_HEAP_SIZE - 1);
+	}
+
 	if ((unsigned long)output & (MIN_KERNEL_ALIGN - 1))
 		error("Destination address inappropriately aligned");
 #ifdef CONFIG_X86_64

arch/x86/boot/main.c +2 -4

Index: linux-2.6/arch/x86/boot/main.c
===================================================================
@@ -132,6 +132,8 @@ void main(void)
 
 	/* Initialize the early-boot console */
 	console_init();
+	if (cmdline_find_option_bool("debug"))
+		puts("early console in setup code\n");
 
 	/* End of heap check */
 	init_heap();

@@ -171,10 +173,6 @@ void main(void)
 	/* Set the video mode */
 	set_video();
 
-	/* Parse command line for 'quiet' and pass it to decompressor. */
-	if (cmdline_find_option_bool("quiet"))
-		boot_params.hdr.loadflags |= QUIET_FLAG;
-
 	/* Do the last things and invoke protected mode */
 	go_to_protected_mode();
 }

arch/x86/boot/compressed/Makefile +2 -2

Index: linux-2.6/arch/x86/boot/compressed/Makefile
===================================================================
@@ -4,7 +4,7 @@
 # create a compressed vmlinux image from the original vmlinux
 #
 
-targets := vmlinux.lds vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma vmlinux.bin.lzo head_$(BITS).o misc.o piggy.o
+targets := vmlinux.lds vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma vmlinux.bin.lzo head_$(BITS).o misc.o string.o printf.o cmdline.o early_serial_console.o piggy.o
 
 KBUILD_CFLAGS := -m$(BITS) -D__KERNEL__ $(LINUX_INCLUDE) -O2
 KBUILD_CFLAGS += -fno-strict-aliasing -fPIC

@@ -23,7 +23,7 @@ LDFLAGS_vmlinux := -T
 
 hostprogs-y	:= mkpiggy
 
-$(obj)/vmlinux: $(obj)/vmlinux.lds $(obj)/head_$(BITS).o $(obj)/misc.o $(obj)/piggy.o FORCE
+$(obj)/vmlinux: $(obj)/vmlinux.lds $(obj)/head_$(BITS).o $(obj)/misc.o $(obj)/string.o $(obj)/printf.o $(obj)/cmdline.o $(obj)/early_serial_console.o $(obj)/piggy.o FORCE
 	$(call if_changed,ld)
 	@:

arch/x86/boot/compressed/cmdline.c new file +21 -0

Index: linux-2.6/arch/x86/boot/compressed/cmdline.c
===================================================================
@@ -0,0 +1,21 @@
+#include "misc.h"
+
+static unsigned long fs;
+static inline void set_fs(unsigned long seg)
+{
+	fs = seg << 4;  /* shift it back */
+}
+typedef unsigned long addr_t;
+static inline char rdfs8(addr_t addr)
+{
+	return *((char *)(fs + addr));
+}
+#include "../cmdline.c"
+int cmdline_find_option(const char *option, char *buffer, int bufsize)
+{
+	return __cmdline_find_option(real_mode->hdr.cmd_line_ptr, option, buffer, bufsize);
+}
+int cmdline_find_option_bool(const char *option)
+{
+	return __cmdline_find_option_bool(real_mode->hdr.cmd_line_ptr, option);
+}

arch/x86/boot/compressed/early_serial_console.c new file +4 -0

Index: linux-2.6/arch/x86/boot/compressed/early_serial_console.c
===================================================================
@@ -0,0 +1,4 @@
+#include "misc.h"
+
+int early_serial_base;
+#include "../early_serial_console.c"

arch/x86/boot/compressed/misc.h new file +38 -0

Index: linux-2.6/arch/x86/boot/compressed/misc.h
===================================================================
@@ -0,0 +1,38 @@
+#ifndef BOOT_COMPRESSED_MISC_H
+#define BOOT_COMPRESSED_MISC_H
+
+/*
+ * we have to be careful, because no indirections are allowed here, and
+ * paravirt_ops is a kind of one. As it will only run in baremetal anyway,
+ * we just keep it from happening
+ */
+#undef CONFIG_PARAVIRT
+#ifdef CONFIG_X86_32
+#define _ASM_X86_DESC_H 1
+#endif
+
+#include <linux/linkage.h>
+#include <linux/screen_info.h>
+#include <linux/elf.h>
+#include <linux/io.h>
+#include <asm/page.h>
+#include <asm/boot.h>
+#include <asm/bootparam.h>
+
+#define BOOT_BOOT_H
+
+/* misc.c */
+extern struct boot_params *real_mode;		/* Pointer to real-mode data */
+void __putstr(int error, const char *s);
+#define putstr(__x)  __putstr(0, __x)
+#define puts(__x)  __putstr(0, __x)
+
+/* cmdline.c */
+int cmdline_find_option(const char *option, char *buffer, int bufsize);
+int cmdline_find_option_bool(const char *option);
+
+/* early_serial_console.c */
+extern int early_serial_base;
+void console_init(void);
+
+#endif

arch/x86/boot/compressed/printf.c new file +4 -0

Index: linux-2.6/arch/x86/boot/compressed/printf.c
===================================================================
@@ -0,0 +1,4 @@
+#include "misc.h"
+
+#include "../isdigit.h"
+#include "../printf.c"

arch/x86/boot/compressed/string.c new file +4 -0

Index: linux-2.6/arch/x86/boot/compressed/string.c
===================================================================
@@ -0,0 +1,4 @@
+#include "misc.h"
+
+#include "../isdigit.h"
+#include "../string.c"

H. Peter Anvin

reviewer

2010-08-02 22:47 UTC #18 lore raw

Re: [PATCH -v3 2/2] x86: more early console output from compressed/misc.c

First, I'm not quite sure which 1/2 patch you're expecting this to be compiled against.

arch/x86/boot/compressed/misc.c asmlinkage void decompress_kernel(void * · line 344

Quoted 11 lines · Yinghai Lu

arch/x86/boot/compressed/misc.c +10 -0

+	if (debug) {
+		putstr("decompress_kernel:\n");
+		printf("  input: [0x%lx-0x%lx], output: 0x%lx, heap: [0x%lx-0x%lx]\n",
+			 (unsigned long)input_data,
+			 (unsigned long)input_data + input_len - 1,
+			 (unsigned long)output,
+			 (unsigned long)heap,
+			 (unsigned long)heap + BOOT_HEAP_SIZE - 1);
+	}
+

This seems to be the only user of printf() in the code. As such, I really suspect it's not worth pulling in all of printf(). I'd be willing to be convinced, but if so I need (a) a concrete usage case, and
(b) it should be a separate patch.

-hpa

Yinghai Lu

author

2010-08-02 22:52 UTC #19 lore raw

Re: [PATCH -v3 2/2] x86: more early console output from compressed/misc.c

Quoted 2 lines · H. Peter Anvin

First, I'm not quite sure which 1/2 patch you're expecting this to be compiled against.

-v3

Quoted 18 lines · Yinghai Lu

arch/x86/boot/compressed/misc.c asmlinkage void decompress_kernel(void * · line 344
Quoted 11 lines
arch/x86/boot/compressed/misc.c +10 -0
+	if (debug) {
+		putstr("decompress_kernel:\n");
+		printf("  input: [0x%lx-0x%lx], output: 0x%lx, heap: [0x%lx-0x%lx]\n",
+			 (unsigned long)input_data,
+			 (unsigned long)input_data + input_len - 1,
+			 (unsigned long)output,
+			 (unsigned long)heap,
+			 (unsigned long)heap + BOOT_HEAP_SIZE - 1);
+	}
+
This seems to be the only user of printf() in the code. As such, I really suspect it's not worth pulling in all of printf(). I'd be willing to be convinced, but if so I need (a) a concrete usage case, and
(b) it should be a separate patch.

ok, will drop printf.

Yinghai

Yinghai Lu

author

2010-08-02 23:22 UTC #20 lore raw

Re: [PATCH -v3 2/2] x86: more early console output from compressed/misc.c

Quoted 27 lines · Yinghai Lu

Quoted 2 lines · H. Peter Anvin
First, I'm not quite sure which 1/2 patch you're expecting this to be compiled against.
-v3
Quoted 18 lines · Yinghai Lu
Review
Quoted 11 lines
(quoted diff) +10 -0
+	if (debug) {
+		putstr("decompress_kernel:\n");
+		printf("  input: [0x%lx-0x%lx], output: 0x%lx, heap: [0x%lx-0x%lx]\n",
+			 (unsigned long)input_data,
+			 (unsigned long)input_data + input_len - 1,
+			 (unsigned long)output,
+			 (unsigned long)heap,
+			 (unsigned long)heap + BOOT_HEAP_SIZE - 1);
+	}
+
This seems to be the only user of printf() in the code. As such, I really suspect it's not worth pulling in all of printf(). I'd be willing to be convinced, but if so I need (a) a concrete usage case, and
(b) it should be a separate patch.

Quoted 2 lines

ok, will drop printf.

please check..

Subject: [PATCH -v5 2/2] x86: more early console output from compressed/misc.c

will get

|Decompressing Linux... Parsing ELF... done.
|Booting the kernel.

in serial console.

reuse code from arch/x86/boot/
and we can use printf if needed

Signed-off-by Yinghai Lu <[email protected]>

---
 arch/x86/boot/compressed/Makefile               |    4 -
 arch/x86/boot/compressed/cmdline.c              |   21 +++++++++
 arch/x86/boot/compressed/early_serial_console.c |    5 ++
 arch/x86/boot/compressed/misc.c                 |   56 ++++++++++++++----------
 arch/x86/boot/compressed/misc.h                 |   38 ++++++++++++++++
 arch/x86/boot/compressed/string.c               |    4 +
 arch/x86/boot/main.c                            |    6 --
 7 files changed, 105 insertions(+), 29 deletions(-)

arch/x86/boot/compressed/misc.c +33 ~~-23~~

Index: linux-2.6/arch/x86/boot/compressed/misc.c
===================================================================
@@ -9,23 +9,7 @@
  * High loaded stuff by Hans Lermen & Werner Almesberger, Feb. 1996
  */
 
-/*
- * we have to be careful, because no indirections are allowed here, and
- * paravirt_ops is a kind of one. As it will only run in baremetal anyway,
- * we just keep it from happening
- */
-#undef CONFIG_PARAVIRT
-#ifdef CONFIG_X86_32
-#define _ASM_X86_DESC_H 1
-#endif
-
-#include <linux/linkage.h>
-#include <linux/screen_info.h>
-#include <linux/elf.h>
-#include <linux/io.h>
-#include <asm/page.h>
-#include <asm/boot.h>
-#include <asm/bootparam.h>
+#include "misc.h"
 
 /* WARNING!!
  * This code is compiled with -fPIC and it is relocated dynamically

@@ -123,15 +107,13 @@ static void error(char *m);
 /*
  * This is set up by the setup-routine at boot-time
  */
-static struct boot_params *real_mode;		/* Pointer to real-mode data */
+struct boot_params *real_mode;		/* Pointer to real-mode data */
 static int quiet;
+static int debug;
 
 void *memset(void *s, int c, size_t n);
 void *memcpy(void *dest, const void *src, size_t n);
 
-static void __putstr(int, const char *);
-#define putstr(__x)  __putstr(0, __x)
-
 #ifdef CONFIG_X86_64
 #define memptr long
 #else

@@ -170,7 +152,21 @@ static void scroll(void)
 		vidmem[i] = ' ';
 }
 
-static void __putstr(int error, const char *s)
+#define XMTRDY          0x20
+
+#define TXR             0       /*  Transmit register (WRITE) */
+#define LSR             5       /*  Line Status               */
+static void serial_putchar(int ch)
+{
+	unsigned timeout = 0xffff;
+
+	while ((inb(early_serial_base + LSR) & XMTRDY) == 0 && --timeout)
+		cpu_relax();
+
+	outb(ch, early_serial_base + TXR);
+}
+
+void __putstr(int error, const char *s)
 {
 	int x, y, pos;
 	char c;

@@ -179,6 +175,14 @@ static void __putstr(int error, const ch
 	if (!error)
 		return;
 #endif
+	if (early_serial_base) {
+		const char *str = s;
+		while (*str) {
+			if (*str == '\n')
+				serial_putchar('\r');
+			serial_putchar(*str++);
+		}
+	}
 
 	if (real_mode->screen_info.orig_video_mode == 0 &&
 	    lines == 0 && cols == 0)

@@ -305,8 +309,10 @@ asmlinkage void decompress_kernel(void *
 {
 	real_mode = rmode;
 
-	if (real_mode->hdr.loadflags & QUIET_FLAG)
+	if (cmdline_find_option_bool("quiet"))
 		quiet = 1;
+	if (cmdline_find_option_bool("debug"))
+		debug = 1;
 
 	if (real_mode->screen_info.orig_video_mode == 7) {
 		vidmem = (char *) 0xb0000;

@@ -319,6 +325,10 @@ asmlinkage void decompress_kernel(void *
 	lines = real_mode->screen_info.orig_video_lines;
 	cols = real_mode->screen_info.orig_video_cols;
 
+	console_init();
+	if (debug)
+		putstr("early console in decompress_kernel\n");
+
 	free_mem_ptr     = heap;	/* Heap */
 	free_mem_end_ptr = heap + BOOT_HEAP_SIZE;

arch/x86/boot/main.c +2 -4

Index: linux-2.6/arch/x86/boot/main.c
===================================================================
@@ -132,6 +132,8 @@ void main(void)
 
 	/* Initialize the early-boot console */
 	console_init();
+	if (cmdline_find_option_bool("debug"))
+		puts("early console in setup code\n");
 
 	/* End of heap check */
 	init_heap();

@@ -171,10 +173,6 @@ void main(void)
 	/* Set the video mode */
 	set_video();
 
-	/* Parse command line for 'quiet' and pass it to decompressor. */
-	if (cmdline_find_option_bool("quiet"))
-		boot_params.hdr.loadflags |= QUIET_FLAG;
-
 	/* Do the last things and invoke protected mode */
 	go_to_protected_mode();
 }

arch/x86/boot/compressed/Makefile +2 -2

Index: linux-2.6/arch/x86/boot/compressed/Makefile
===================================================================
@@ -4,7 +4,7 @@
 # create a compressed vmlinux image from the original vmlinux
 #
 
-targets := vmlinux.lds vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma vmlinux.bin.lzo head_$(BITS).o misc.o piggy.o
+targets := vmlinux.lds vmlinux vmlinux.bin vmlinux.bin.gz vmlinux.bin.bz2 vmlinux.bin.lzma vmlinux.bin.lzo head_$(BITS).o misc.o string.o cmdline.o early_serial_console.o piggy.o
 
 KBUILD_CFLAGS := -m$(BITS) -D__KERNEL__ $(LINUX_INCLUDE) -O2
 KBUILD_CFLAGS += -fno-strict-aliasing -fPIC

@@ -23,7 +23,7 @@ LDFLAGS_vmlinux := -T
 
 hostprogs-y	:= mkpiggy
 
-$(obj)/vmlinux: $(obj)/vmlinux.lds $(obj)/head_$(BITS).o $(obj)/misc.o $(obj)/piggy.o FORCE
+$(obj)/vmlinux: $(obj)/vmlinux.lds $(obj)/head_$(BITS).o $(obj)/misc.o $(obj)/string.o $(obj)/cmdline.o $(obj)/early_serial_console.o $(obj)/piggy.o FORCE
 	$(call if_changed,ld)
 	@:

arch/x86/boot/compressed/cmdline.c new file +21 -0

Index: linux-2.6/arch/x86/boot/compressed/cmdline.c
===================================================================
@@ -0,0 +1,21 @@
+#include "misc.h"
+
+static unsigned long fs;
+static inline void set_fs(unsigned long seg)
+{
+	fs = seg << 4;  /* shift it back */
+}
+typedef unsigned long addr_t;
+static inline char rdfs8(addr_t addr)
+{
+	return *((char *)(fs + addr));
+}
+#include "../cmdline.c"
+int cmdline_find_option(const char *option, char *buffer, int bufsize)
+{
+	return __cmdline_find_option(real_mode->hdr.cmd_line_ptr, option, buffer, bufsize);
+}
+int cmdline_find_option_bool(const char *option)
+{
+	return __cmdline_find_option_bool(real_mode->hdr.cmd_line_ptr, option);
+}

arch/x86/boot/compressed/early_serial_console.c new file +5 -0

Index: linux-2.6/arch/x86/boot/compressed/early_serial_console.c
===================================================================
@@ -0,0 +1,5 @@
+#include "misc.h"
+
+int early_serial_base;
+
+#include "../early_serial_console.c"

arch/x86/boot/compressed/misc.h new file +38 -0

Index: linux-2.6/arch/x86/boot/compressed/misc.h
===================================================================
@@ -0,0 +1,38 @@
+#ifndef BOOT_COMPRESSED_MISC_H
+#define BOOT_COMPRESSED_MISC_H
+
+/*
+ * we have to be careful, because no indirections are allowed here, and
+ * paravirt_ops is a kind of one. As it will only run in baremetal anyway,
+ * we just keep it from happening
+ */
+#undef CONFIG_PARAVIRT
+#ifdef CONFIG_X86_32
+#define _ASM_X86_DESC_H 1
+#endif
+
+#include <linux/linkage.h>
+#include <linux/screen_info.h>
+#include <linux/elf.h>
+#include <linux/io.h>
+#include <asm/page.h>
+#include <asm/boot.h>
+#include <asm/bootparam.h>
+
+#define BOOT_BOOT_H
+
+/* misc.c */
+extern struct boot_params *real_mode;		/* Pointer to real-mode data */
+void __putstr(int error, const char *s);
+#define putstr(__x)  __putstr(0, __x)
+#define puts(__x)  __putstr(0, __x)
+
+/* cmdline.c */
+int cmdline_find_option(const char *option, char *buffer, int bufsize);
+int cmdline_find_option_bool(const char *option);
+
+/* early_serial_console.c */
+extern int early_serial_base;
+void console_init(void);
+
+#endif

arch/x86/boot/compressed/string.c new file +4 -0

Index: linux-2.6/arch/x86/boot/compressed/string.c
===================================================================
@@ -0,0 +1,4 @@
+#include "misc.h"
+
+#include "../isdigit.h"
+#include "../string.c"

tip-bot for H. Peter Anvin

2010-08-03 03:31 UTC #22 lore raw

[tip:x86/setup] x86, setup: Allow global variables and functions in the decompressor

Commit-ID:  22a57f5896df218356bae6203dfaf04bcfd6c88c
Gitweb:     http://git.kernel.org/tip/22a57f5896df218356bae6203dfaf04bcfd6c88c
Author:     H. Peter Anvin <[email protected]>
AuthorDate: Mon, 2 Aug 2010 15:34:44 -0700
Committer:  H. Peter Anvin <[email protected]>
CommitDate: Mon, 2 Aug 2010 15:34:44 -0700

x86, setup: Allow global variables and functions in the decompressor

In order for global variables and functions to work in the decompressor, we need to fix up the GOT in assembly code.

Signed-off-by H. Peter Anvin <[email protected]>

LKML-Reference: <[email protected]>

---
 arch/x86/boot/compressed/head_32.S     |   13 +++++++++++++
 arch/x86/boot/compressed/head_64.S     |   13 +++++++++++++
 arch/x86/boot/compressed/vmlinux.lds.S |    6 ++++++
 3 files changed, 32 insertions(+), 0 deletions(-)

arch/x86/boot/compressed/head_32.S +13 -0

index f543b70..67a655a 100644
@@ -124,6 +124,19 @@ relocated:
 	rep	stosl
 
 /*
+ * Adjust our own GOT
+ */
+	leal	_got(%ebx), %edx
+	leal	_egot(%ebx), %ecx
+1:
+	cmpl	%ecx, %edx
+	jae	2f
+	addl	%ebx, (%edx)
+	addl	$4, %edx
+	jmp	1b
+2:
+
+/*
  * Do the decompression, and jump to the new kernel..
  */
 	leal	z_extract_offset_negative(%ebx), %ebp

arch/x86/boot/compressed/head_64.S +13 -0

index faff0dc..52f85a1 100644
@@ -280,6 +280,19 @@ relocated:
 	rep	stosq
 
 /*
+ * Adjust our own GOT
+ */
+	leaq	_got(%rip), %rdx
+	leaq	_egot(%rip), %rcx
+1:
+	cmpq	%rcx, %rdx
+	jae	2f
+	addq	%rbx, (%rdx)
+	addq	$8, %rdx
+	jmp	1b
+2:
+	
+/*
  * Do the decompression, and jump to the new kernel..
  */
 	pushq	%rsi			/* Save the real mode argument */

arch/x86/boot/compressed/vmlinux.lds.S +6 -0

index 5ddabce..34d047c 100644
@@ -41,6 +41,12 @@ SECTIONS
 		*(.rodata.*)
 		_erodata = . ;
 	}
+	.got : {
+		_got = .;
+		KEEP(*(.got.plt))
+		KEEP(*(.got))
+		_egot = .;
+	}
 	.data :	{
 		_data = . ;
 		*(.data)

tip-bot for Yinghai Lu

author

2010-08-03 03:31 UTC #25 lore raw

[tip:x86/setup] x86, setup: reorganize the early console setup

Commit-ID:  f4ed2877b16e8146427306aea8819adac5c88374
Gitweb:     http://git.kernel.org/tip/f4ed2877b16e8146427306aea8819adac5c88374
Author:     Yinghai Lu <[email protected]>
AuthorDate: Mon, 2 Aug 2010 02:17:31 -0700
Committer:  H. Peter Anvin <[email protected]>
CommitDate: Mon, 2 Aug 2010 15:51:56 -0700

x86, setup: reorganize the early console setup

Separate early_serial_console from tty.c

This allows for reuse of early_serial_console.c/string.c/printf.c/cmdline.c in boot/compressed/.

-v2: according to hpa, don't include string.c etc
-v3: compressed/misc.c must have early_serial_base as static, so move it back to tty.c
for setup code

Signed-off-by Yinghai Lu <[email protected]>

LKML-Reference: <[email protected]>

Signed-off-by H. Peter Anvin <[email protected]>

---
 arch/x86/boot/Makefile               |    8 +-
 arch/x86/boot/boot.h                 |   35 ++++-----
 arch/x86/boot/cmdline.c              |    6 +-
 arch/x86/boot/early_serial_console.c |  139 ++++++++++++++++++++++++++++++++++
 arch/x86/boot/isdigit.h              |   21 +++++
 arch/x86/boot/printf.c               |    4 +-
 arch/x86/boot/tty.c                  |  136 +---------------------------------
 7 files changed, 186 insertions(+), 163 deletions(-)

arch/x86/boot/Makefile +4 -4

index ec749c2..f7cb086 100644
@@ -26,10 +26,10 @@ targets		:= vmlinux.bin setup.bin setup.elf bzImage
 targets		+= fdimage fdimage144 fdimage288 image.iso mtools.conf
 subdir-		:= compressed
 
-setup-y		+= a20.o bioscall.o cmdline.o copy.o cpu.o cpucheck.o edd.o
-setup-y		+= header.o main.o mca.o memory.o pm.o pmjump.o
-setup-y		+= printf.o regs.o string.o tty.o video.o video-mode.o
-setup-y		+= version.o
+setup-y		+= a20.o bioscall.o cmdline.o copy.o cpu.o cpucheck.o
+setup-y		+= early_serial_console.o edd.o header.o main.o mca.o memory.o
+setup-y		+= pm.o pmjump.o printf.o regs.o string.o tty.o video.o
+setup-y		+= video-mode.o version.o
 setup-$(CONFIG_X86_APM_BOOT) += apm.o
 
 # The link order of the video-*.o modules can matter.  In particular,

arch/x86/boot/boot.h +17 ~~-18~~

index 46c4c5c..00cf51c 100644
@@ -200,21 +200,7 @@ static inline int memcmp_gs(const void *s1, addr_t s2, size_t len)
 	return diff;
 }
 
-static inline int isdigit(int ch)
-{
-	return (ch >= '0') && (ch <= '9');
-}
-
-static inline int isxdigit(int ch)
-{
-	if (isdigit(ch))
-		return true;
-
-	if ((ch >= 'a') && (ch <= 'f'))
-		return true;
-
-	return (ch >= 'A') && (ch <= 'F');
-}
+#include "isdigit.h"
 
 /* Heap -- available for dynamic lists. */
 extern char _end[];

@@ -300,8 +286,18 @@ struct biosregs {
 void intcall(u8 int_no, const struct biosregs *ireg, struct biosregs *oreg);
 
 /* cmdline.c */
-int cmdline_find_option(const char *option, char *buffer, int bufsize);
-int cmdline_find_option_bool(const char *option);
+int __cmdline_find_option(u32 cmdline_ptr, const char *option, char *buffer, int bufsize);
+int __cmdline_find_option_bool(u32 cmdline_ptr, const char *option);
+static inline int cmdline_find_option(const char *option, char *buffer, int bufsize)
+{
+	return __cmdline_find_option(boot_params.hdr.cmd_line_ptr, option, buffer, bufsize);
+}
+
+static inline int cmdline_find_option_bool(const char *option)
+{
+	return __cmdline_find_option_bool(boot_params.hdr.cmd_line_ptr, option);
+}
+
 
 /* cpu.c, cpucheck.c */
 struct cpu_features {

@@ -313,6 +309,10 @@ extern struct cpu_features cpu;
 int check_cpu(int *cpu_level_ptr, int *req_level_ptr, u32 **err_flags_ptr);
 int validate_cpu(void);
 
+/* early_serial_console.c */
+extern int early_serial_base;
+void console_init(void);
+
 /* edd.c */
 void query_edd(void);

@@ -348,7 +348,6 @@ unsigned int atou(const char *s);
 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base);
 
 /* tty.c */
-void console_init(void);
 void puts(const char *);
 void putchar(int);
 int getchar(void);

arch/x86/boot/cmdline.c +2 -4

index a1d3563..6b3b6f7 100644
@@ -27,9 +27,8 @@ static inline int myisspace(u8 c)
  * Returns the length of the argument (regardless of if it was
  * truncated to fit in the buffer), or -1 on not found.
  */
-int cmdline_find_option(const char *option, char *buffer, int bufsize)
+int __cmdline_find_option(u32 cmdline_ptr, const char *option, char *buffer, int bufsize)
 {
-	u32 cmdline_ptr = boot_params.hdr.cmd_line_ptr;
 	addr_t cptr;
 	char c;
 	int len = -1;

@@ -100,9 +99,8 @@ int cmdline_find_option(const char *option, char *buffer, int bufsize)
  * Returns the position of that option (starts counting with 1)
  * or 0 on not found
  */
-int cmdline_find_option_bool(const char *option)
+int __cmdline_find_option_bool(u32 cmdline_ptr, const char *option)
 {
-	u32 cmdline_ptr = boot_params.hdr.cmd_line_ptr;
 	addr_t cptr;
 	char c;
 	int pos = 0, wstart = 0;

arch/x86/boot/early_serial_console.c new file +139 -0

139 lines not on this page · raw message

arch/x86/boot/isdigit.h new file +21 -0

new file mode 100644
index 0000000..25e1340
@@ -0,0 +1,21 @@
+#ifndef BOOT_ISDIGIT_H
+
+#define BOOT_ISDIGIT_H
+
+static inline int isdigit(int ch)
+{
+	return (ch >= '0') && (ch <= '9');
+}
+
+static inline int isxdigit(int ch)
+{
+	if (isdigit(ch))
+		return true;
+
+	if ((ch >= 'a') && (ch <= 'f'))
+		return true;
+
+	return (ch >= 'A') && (ch <= 'F');
+}
+
+#endif

arch/x86/boot/printf.c +2 -2

index 50e47cd..cdac91c 100644
@@ -34,7 +34,7 @@ static int skip_atoi(const char **s)
 #define SMALL	32		/* Must be 32 == 0x20 */
 #define SPECIAL	64		/* 0x */
 
-#define do_div(n,base) ({ \
+#define __do_div(n, base) ({ \
 int __res; \
 __res = ((unsigned long) n) % (unsigned) base; \
 n = ((unsigned long) n) / (unsigned) base; \

@@ -83,7 +83,7 @@ static char *number(char *str, long num, int base, int size, int precision,
 		tmp[i++] = '0';
 	else
 		while (num != 0)
-			tmp[i++] = (digits[do_div(num, base)] | locase);
+			tmp[i++] = (digits[__do_div(num, base)] | locase);
 	if (i > precision)
 		precision = i;
 	size -= precision;

arch/x86/boot/tty.c +1 ~~-135~~

150 lines not on this page · raw message

tip-bot for H. Peter Anvin

reviewer

2010-08-03 04:10 UTC #21 lore raw

[tip:x86/setup] x86, setup: move isdigit.h to ctype.h, header files on top.

Commit-ID:  6238b47b58480cd9c092600c05338dbe261b71ce
Gitweb:     http://git.kernel.org/tip/6238b47b58480cd9c092600c05338dbe261b71ce
Author:     H. Peter Anvin <[email protected]>
AuthorDate: Mon, 2 Aug 2010 21:03:46 -0700
Committer:  H. Peter Anvin <[email protected]>
CommitDate: Mon, 2 Aug 2010 21:07:20 -0700

x86, setup: move isdigit.h to ctype.h, header files on top.

It is a subset of <ctype.h> functionality, so name it ctype.h. Also, reorganize header files so #include statements are clustered near the top as they should be.

Signed-off-by H. Peter Anvin <[email protected]>

LKML-Reference: <[email protected]>

---
 arch/x86/boot/boot.h                 |    3 +--
 arch/x86/boot/compressed/misc.h      |    1 +
 arch/x86/boot/compressed/string.c    |    2 --
 arch/x86/boot/{isdigit.h => ctype.h} |    0
 4 files changed, 2 insertions(+), 4 deletions(-)

arch/x86/boot/boot.h +1 -2

index 00cf51c..c7093bd 100644
@@ -28,6 +28,7 @@
 #include "bitops.h"
 #include <asm/cpufeature.h>
 #include <asm/processor-flags.h>
+#include "ctype.h"
 
 /* Useful macros */
 #define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))

@@ -200,8 +201,6 @@ static inline int memcmp_gs(const void *s1, addr_t s2, size_t len)
 	return diff;
 }
 
-#include "isdigit.h"
-
 /* Heap -- available for dynamic lists. */
 extern char _end[];
 extern char *HEAP;

arch/x86/boot/compressed/misc.h +1 -0

index a267849..3f19c81 100644
@@ -20,6 +20,7 @@
 #include <asm/bootparam.h>
 
 #define BOOT_BOOT_H
+#include "../ctype.h"
 
 /* misc.c */
 extern struct boot_params *real_mode;		/* Pointer to real-mode data */

arch/x86/boot/compressed/string.c +0 -2

index 7995c6a..19b3e69 100644
@@ -1,4 +1,2 @@
 #include "misc.h"
-
-#include "../isdigit.h"
 #include "../string.c"

arch/x86/boot/ctype.h renamed from arch/x86/boot/isdigit.h +0 -0

similarity index 100%
rename from arch/x86/boot/isdigit.h
rename to arch/x86/boot/ctype.h

Yinghai Lu

author

2010-08-03 07:17 UTC #33 lore raw

PATCH 1/1 x86: Setup early console as early as possible

In reply to Andrew Morton

Analyze "console=uart8250,io,0x3f8,115200n8" in i386_start_kernel/x86_64_start_kernel, and call setup_early_serial8250_console() to init early serial console.

only can handle io port kind of 8250. because mmio need ioremap.

-v2: use boot_params.hdr.version instead of adding another variable, Suggested by hpa
update after using x86 memblock patchset
-v3: x86 memblock can not make into with 2.6.36 now
so update this patch to be applied before x86 memblock patchset again.

Signed-off-by Yinghai Lu <[email protected]>

---
 arch/x86/include/asm/setup.h |    2 ++
 arch/x86/kernel/head.c       |   26 ++++++++++++++++++++++++++
 arch/x86/kernel/head32.c     |    2 ++
 arch/x86/kernel/head64.c     |   13 ++++++++++++-
 kernel/printk.c              |    4 ++++
 5 files changed, 46 insertions(+), 1 deletion(-)

arch/x86/include/asm/setup.h +2 -0

Index: linux-2.6/arch/x86/include/asm/setup.h
===================================================================
@@ -42,6 +42,8 @@ static inline void visws_early_detect(vo
 #endif
 
 extern unsigned long saved_video_mode;
+int setup_early_serial8250_console(char *cmdline);
+void setup_early_console(void);
 
 extern void reserve_standard_io_resources(void);
 extern void i386_reserve_resources(void);

arch/x86/kernel/head.c +26 -0

Index: linux-2.6/arch/x86/kernel/head.c
===================================================================
@@ -53,3 +53,29 @@ void __init reserve_ebda_region(void)
 	/* reserve all memory between lowmem and the 1MB mark */
 	reserve_early_overlap_ok(lowmem, 0x100000, "BIOS reserved");
 }
+
+void __init setup_early_console(void)
+{
+#ifdef CONFIG_SERIAL_8250_CONSOLE
+	char constr[64], *p, *q;
+
+	/* Can not handle mmio type 8250 uart yet, too early */
+	p = strstr(boot_command_line, "console=uart8250,io,");
+	if (!p)
+		p = strstr(boot_command_line, "console=uart,io,");
+	if (!p)
+		return;
+
+	p += 8;	/* sizeof "console=" */
+	q = strchr(p, ' ');
+	if ((q - p) >= sizeof(constr))
+		return;
+
+	memset(constr, 0, sizeof(constr));
+	memcpy(constr, p, q - p);
+
+	lockdep_init();
+
+	setup_early_serial8250_console(constr);
+#endif
+}

arch/x86/kernel/head32.c +2 -0

Index: linux-2.6/arch/x86/kernel/head32.c
===================================================================
@@ -30,6 +30,8 @@ static void __init i386_default_early_se
 
 void __init i386_start_kernel(void)
 {
+	setup_early_console();
+
 #ifdef CONFIG_X86_TRAMPOLINE
 	/*
 	 * But first pinch a few for the stack/trampoline stuff

arch/x86/kernel/head64.c +12 -1

Index: linux-2.6/arch/x86/kernel/head64.c
===================================================================
@@ -73,6 +73,10 @@ void __init x86_64_start_kernel(char * r
 	/* clear bss before set_intr_gate with early_idt_handler */
 	clear_bss();
 
+	/* boot_params is in bss */
+	copy_bootdata(__va(real_mode_data));
+	setup_early_console();
+
 	/* Make NULL pointers segfault */
 	zap_identity_mappings();

@@ -96,7 +100,14 @@ void __init x86_64_start_kernel(char * r
 
 void __init x86_64_start_reservations(char *real_mode_data)
 {
-	copy_bootdata(__va(real_mode_data));
+	/*
+	 * hdr.version is always not 0, so check it to see
+	 *  if boot_params is copied or not.
+	 */
+	if (!boot_params.hdr.version) {
+		copy_bootdata(__va(real_mode_data));
+		setup_early_console();
+	}
 
 	reserve_early(__pa_symbol(&_text), __pa_symbol(&__bss_stop), "TEXT DATA BSS");

kernel/printk.c +4 -0

Index: linux-2.6/kernel/printk.c
===================================================================
@@ -1203,6 +1203,10 @@ void register_console(struct console *ne
 	if (console_drivers && newcon->flags & CON_BOOT) {
 		/* find the last or real console */
 		for_each_console(bcon) {
+			/* not again */
+			if (bcon == newcon)
+				return;
+
 			if (!(bcon->flags & CON_BOOT)) {
 				printk(KERN_INFO "Too late to register bootconsole %s%d\n",
 					newcon->name, newcon->index);

Andrew Morton

2010-08-03 09:06 UTC #34 lore raw

Re: [PATCH -v3] x86: Setup early console as early as possible

Quoted 16 lines · On Tue, 03 Aug 2010 00:14:38 -0700 Yinghai Lu <[email protected]> wrote:

Analyze "console=uart8250,io,0x3f8,115200n8" in i386_start_kernel/x86_64_start_kernel, and call setup_early_serial8250_console() to init early serial console.
only can handle io port kind of 8250. because mmio need ioremap.
(quoted diff) +0 -2
-v2: use boot_params.hdr.version instead of adding another variable, Suggested by hpa
     update after using x86 memblock patchset
-v3: x86 memblock can not make into with 2.6.36 now
     so update this patch to be applied before x86 memblock patchset again.
 
...

kernel/printk.c void register_console(struct console *ne · line 1211

Quoted 9 lines

kernel/printk.c +4 -0

@@ -1203,6 +1203,10 @@ void register_console(struct console *ne
 	if (console_drivers && newcon->flags & CON_BOOT) {
 		/* find the last or real console */
 		for_each_console(bcon) {
+			/* not again */
+			if (bcon == newcon)
+				return;
+
 			if (!(bcon->flags & CON_BOOT)) {
 				printk(KERN_INFO "Too late to register bootconsole %s%d\n",

Why this change?

Yinghai Lu

author

2010-08-03 09:10 UTC #35 lore raw

Re: [PATCH -v3] x86: Setup early console as early as possible

Quoted 15 lines · Andrew Morton

Quoted 13 lines · On Tue, 03 Aug 2010 00:14:38 -0700 Yinghai Lu <[email protected]> wrote:
Analyze "console=uart8250,io,0x3f8,115200n8" in i386_start_kernel/x86_64_start_kernel, and call setup_early_serial8250_console() to init early serial console.
only can handle io port kind of 8250. because mmio need ioremap.
(quoted diff) +0 -2
-v2: use boot_params.hdr.version instead of adding another variable, Suggested by hpa
     update after using x86 memblock patchset
-v3: x86 memblock can not make into with 2.6.36 now
     so update this patch to be applied before x86 memblock patchset again.
 
...

Quoted 14 lines

kernel/printk.c void register_console(struct console *ne · line 1211

Quoted 12 lines

kernel/printk.c +4 -0

@@ -1203,6 +1203,10 @@ void register_console(struct console *ne
 	if (console_drivers && newcon->flags & CON_BOOT) {
 		/* find the last or real console */
 		for_each_console(bcon) {
+			/* not again */
+			if (bcon == newcon)
+				return;
+
 			if (!(bcon->flags & CON_BOOT)) {
 				printk(KERN_INFO "Too late to register bootconsole %s%d\n",

Why this change?

it seems register the same console as early console will dead loop.

let me double check that again to see if can remove that change.

Yinghai

Yinghai Lu

author

2010-08-03 10:16 UTC #36 lore raw

Re: [PATCH -v3] x86: Setup early console as early as possible

Quoted 15 lines · Andrew Morton

Quoted 13 lines · On Tue, 03 Aug 2010 00:14:38 -0700 Yinghai Lu <[email protected]> wrote:
Analyze "console=uart8250,io,0x3f8,115200n8" in i386_start_kernel/x86_64_start_kernel, and call setup_early_serial8250_console() to init early serial console.
only can handle io port kind of 8250. because mmio need ioremap.
(quoted diff) +0 -2
-v2: use boot_params.hdr.version instead of adding another variable, Suggested by hpa
     update after using x86 memblock patchset
-v3: x86 memblock can not make into with 2.6.36 now
     so update this patch to be applied before x86 memblock patchset again.
 
...

Quoted 14 lines

kernel/printk.c void register_console(struct console *ne · line 1211

Quoted 12 lines

kernel/printk.c +4 -0

@@ -1203,6 +1203,10 @@ void register_console(struct console *ne
 	if (console_drivers && newcon->flags & CON_BOOT) {
 		/* find the last or real console */
 		for_each_console(bcon) {
+			/* not again */
+			if (bcon == newcon)
+				return;
+
 			if (!(bcon->flags & CON_BOOT)) {
 				printk(KERN_INFO "Too late to register bootconsole %s%d\n",

Why this change?

without that will get

early console in setup code
early console in decompress_kernel
decompress_kernel:
input: [0x24a0269-0x2e8b642], output: 0x1000000, heap: [0x2e90e40-0x2e97e3f]

Decompressing Linux... Parsing ELF... done.
Booting the kernel.

[    0.000000] bootconsole [uart0] enabled
[    0.000000] Kernel Layout:
[    0.000000]   .text: [0x01000000-0x01cb210d]
[    0.000000] .rodata: [0x01cb8000-0x02419fff]
[    0.000000]   .data: [0x0241a000-0x025b583f]
[    0.000000]   .init: [0x025b7000-0x02875fff]
[    0.000000]    .bss: [0x02880000-0x0348bb6f]
[    0.000000]    .brk: [0x0348c000-0x034abfff]
[    0.000000]     memblock_x86_reserve_range: [0x01000000-0x0348bb6f]    TEXT DATA BSS
[    0.000000]     memblock_x86_reserve_range: [0x2c6b0000-0x2ffcefff]          RAMDISK
[    0.000000]     memblock_x86_reserve_range: [0x0009fc00-0x000fffff]  * BIOS reserved
[    0.000000] Initializing cgroup subsys cpuset
[    0.000000] Initializing cgroup subsys cpu
[    0.000000] Linux version 2.6.35-tip-yh-01758-g649ef4b-dirty (yhlu@linux-siqj) (gcc version 4.4.1 [gcc-4_4-branch revision 150839] (SUSE Linux) ) #148 SMP Tue Aug 3 03:09:06 PDT 2010
[    0.000000] Command line: BOOT_IMAGE=linux debug apic=debug ramdisk_size=262144 root=/dev/ram0 rw ip=dhcp console=uart8250,io,0x3f8,115200 initrd=initrd.img
[    0.000000] KERNEL supported cpus:
[    0.000000]   Intel GenuineIntel
[    0.000000]   AMD AuthenticAMD
[    0.000000]   Centaur CentaurHauls
[    0.000000] BIOS-provided physical RAM map:
[    0.000000]  BIOS-e820: [0x00000000000000-0x0000000009efff] (usable)
[    0.000000]  BIOS-e820: [0x0000000009f000-0x0000000009ffff] (reserved)
[    0.000000]  BIOS-e820: [0x000000000e8000-0x000000000fffff] (reserved)
[    0.000000]  BIOS-e820: [0x00000000100000-0x0000002ffeffff] (usable)
[    0.000000]  BIOS-e820: [0x0000002fff0000-0x0000002fffffff] (ACPI data)
[    0.000000]  BIOS-e820: [0x000000fffbc000-0x000000ffffffff] (reserved)
[    0.000000] Early serial console at I/O port 0x3f8 (options '115200')
[    0.000000] Early serial console at I/O port 0x3f8 (options '115200')
[    0.000000] Early serial console at I/O port 0x3f8 (options '115200')
[    0.000000] Early serial console at I/O port 0x3f8 (options '115200')

....

Cyrill Gorcunov

2010-08-03 15:07 UTC #37 lore raw

Re: [PATCH -v3] x86: Setup early console as early as possible