Joystick timing for x86-64

PATCH In review Vojtech Pavlik 1 participant 1 message Sep 13, 2001 Char and misc drivers

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Vojtech Pavlik

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2001-09-13 16:47 UTC #0 lore raw

PATCH 8/11 Joystick timing for x86-64

Hi!

This patch adds support for timing on x86-64 in the joystick drivers. It also changes the compile-time configuration of TSC vs PIT timing to runtime - PIT is too slow to notice the extra check and TSC processors are fast enough to make it non-noticeable (and TSC precision is much much more than we need anyway in the joystick drivers).

drivers/char/joystick/analog.c +14 ~~-15~~

diff -urN linux-x86_64/drivers/char/joystick/analog.c linux-64-latest/drivers/char/joystick/analog.c
@@ -39,6 +39,7 @@
 #include <linux/init.h>
 #include <linux/input.h>
 #include <linux/gameport.h>
+#include <asm/timex.h>
 
 MODULE_AUTHOR("Vojtech Pavlik <[email protected]>");
 MODULE_DESCRIPTION("Analog joystick and gamepad driver for Linux");

@@ -135,27 +136,25 @@
  */
 
 #ifdef __i386__
-#ifdef CONFIG_X86_TSC
-#define GET_TIME(x)	__asm__ __volatile__ ( "rdtsc" : "=a" (x) : : "dx" )
+#define TSC_PRESENT	(test_bit(X86_FEATURE_TSC, &boot_cpu_data.x86_capability))
+#define GET_TIME(x)	do { if (TSC_PRESENT) rdtscl(x); else outb(0, 0x43); x = inb(0x40); x |= inb(0x40) << 8; } while (0)
+#define DELTA(x,y)	(TSC_PRESENT?((y)-(x)):((x)-(y)+((x)<(y)?1193180L/HZ:0)))
+#define TIME_NAME	(TSC_PRESENT?"TSC":"PIT")
+#elif __x86_64__
+#define GET_TIME(x)	rdtscl(x)
 #define DELTA(x,y)	((y)-(x))
-#define TIME_NAME "TSC"
-#else
-#define GET_TIME(x)	do { outb(0, 0x43); x = inb(0x40); x |= inb(0x40) << 8; } while (0)
-#define DELTA(x,y)	((x)-(y)+((x)<(y)?1193180L/HZ:0))
-#define TIME_NAME "PIT"
-#endif
+#define TIME_NAME	"TSC"
 #elif __alpha__
-#define GET_TIME(x)	__asm__ __volatile__ ( "rpcc %0" : "=r" (x) )
+#define GET_TIME(x)	get_cycles(x)
 #define DELTA(x,y)	((y)-(x))
-#define TIME_NAME "PCC"
-#endif
-
-#ifndef GET_TIME
+#define TIME_NAME	"PCC"
+#else
 #define FAKE_TIME
 static unsigned long analog_faketime = 0;
 #define GET_TIME(x)     do { x = analog_faketime++; } while(0)
 #define DELTA(x,y)	((y)-(x))
-#define TIME_NAME "Unreliable"
+#define TIME_NAME	"Unreliable"
+#warning Precise timer not defined for this architecture.
 #endif
 
 /*

@@ -497,7 +496,7 @@
 	if (port->cooked)
 		printk(" [ADC port]\n");
 	else
-		printk(" ["TIME_NAME" timer, %d %sHz clock, %d ns res]\n",
+		printk(" [%s timer, %d %sHz clock, %d ns res]\n", TIME_NAME,
 		port->speed > 10000 ? (port->speed + 800) / 1000 : port->speed,
 		port->speed > 10000 ? "M" : "k", (port->loop * 1000000) / port->speed);
 }

drivers/char/joystick/gameport.c +1 -1

diff -urN linux-x86_64/drivers/char/joystick/gameport.c linux-64-latest/drivers/char/joystick/gameport.c
@@ -61,7 +61,7 @@
 
 static int gameport_measure_speed(struct gameport *gameport)
 {
-#ifdef __i386__
+#if defined(__i386__) || defined(__x86_64__)
 
 #define GET_TIME(x)     do { outb(0, 0x43); x = inb(0x40); x |= inb(0x40) << 8; } while (0)
 #define DELTA(x,y)      ((y)-(x)+((y)<(x)?1193180L/HZ:0))

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Vojtech Pavlik
SuSE Labs