loongson: enable serial port support

From bf9563658acaff1b9de721841383eba655ccfd4d Mon Sep 17 00:00:00 2001
From: Wu Zhangjin <[email protected]>
Date: Sat, 16 May 2009 03:34:11 +0800
Subject: [PATCH 15/30] loongson: enable serial port support

this serial port support is portable to loongson-based machines, the old serial port support in fuloong(2e) via HAVE_STD_PC_SERIAL_PORT is replaced by this implementation.

before, only fuloong(2e) used HAVE_STD_PC_SERIAL_PORT kernel option, so, we can remove arch/mips/kernel/8250-platform.c directly.

---
 arch/mips/include/asm/mach-loongson/machine.h |    4 ++
 arch/mips/loongson/common/Makefile            |    5 ++
 arch/mips/loongson/common/serial.c            |   64
+++++++++++++++++++++++++
 3 files changed, 73 insertions(+), 0 deletions(-)
 create mode 100644 arch/mips/loongson/common/serial.c

b/arch/mips/include/asm/mach-loongson/machine.h
index 577b86c..cb48d9b 100644

@@ -18,6 +18,8 @@
 #define MACH_NAME			"lemote-fuloong(2e)"
 
 #define LOONGSON_UART_BASE		0x1fd003f8
+#define LOONGSON_UART_BAUD		1843200	
+#define LOONGSON_UART_IOTYPE		UPIO_PORT
 
 #define LOONGSON_NORTH_BRIDGE_IRQ	(MIPS_CPU_IRQ_BASE + 2)
 #define LOONGSON_UART_IRQ		(MIPS_CPU_IRQ_BASE + 4)

@@ -30,6 +32,8 @@
 #define MACH_NAME			"lemote-fuloong(2f)"
 
 #define LOONGSON_UART_BASE		0x1fd002f8
+#define LOONGSON_UART_BAUD		1843200
+#define LOONGSON_UART_IOTYPE		UPIO_PORT
 
 #define LOONGSON_TIMER_IRQ		(MIPS_CPU_IRQ_BASE + 7)	/* cpu timer */
 #define LOONGSON_PERFCNT_IRQ		(MIPS_CPU_IRQ_BASE + 6)	/* cpu perf

counter */

b/arch/mips/loongson/common/Makefile
index 869adb5..91ba177 100644

@@ -23,4 +23,9 @@ obj-$(CONFIG_RTC_DRV_CMOS) += rtc.o
 #
 obj-$(CONFIG_CS5536) += cs5536_vsm.o
 
+#
+# Enable serial port
+#
+obj-$(CONFIG_SERIAL_8250) += serial.o
+
 EXTRA_CFLAGS += -Werror

b/arch/mips/loongson/common/serial.c
new file mode 100644
index 0000000..683184a

@@ -0,0 +1,64 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General

Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2007 Ralf Baechle ([email protected])
+ *
+ * Copyright (C) 2009 Lemote, Inc. & Institute of Computing Technology
+ * Author: yanhua ([email protected])
+ * Author: Wu Zhangjin ([email protected])
+ */
+
+#include <linux/io.h>
+#include <linux/init.h>
+#include <linux/serial_8250.h>
+
+#include <machine.h>
+
+#define PORT(int, base_baud, io_type) \
+{ \
+ .irq = int, \
+ .uartclk = base_baud, \
+ .iotype = io_type, \
+ .flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST, \
+ .regshift = 0, \
+}
+
+static struct plat_serial8250_port uart8250_data[] = {
+ PORT(LOONGSON_UART_IRQ, LOONGSON_UART_BAUD, LOONGSON_UART_IOTYPE),
+ {},
+};
+
+static struct platform_device uart8250_device = {
+ .name = "serial8250",
+ .id = PLAT8250_DEV_PLATFORM,
+ .dev = {
+ .platform_data = uart8250_data,
+ },
+};
+
+static inline void uart8250_init(void)
+{
+#if (LOONGSON_UART_IOTYPE == UPIO_MEM)
+ uart8250_data[0].membase =
+ ioremap_nocache(LOONGSON_UART_BASE, 8);
+#elif (LOONGSON_UART_IOTYPE == UPIO_PORT)
+ uart8250_data[0].iobase = LOONGSON_UART_BASE & 0x3ff;
+ uart8250_data[0].irq -= MIPS_CPU_IRQ_BASE;
+#else
+#warning currently, no such iotype of uart used in loongson-based machines
+
+#endif
+}
+
+static int __init serial_init(void)
+{
+ uart8250_init();
+
+ platform_device_register(&uart8250_device);
+
+ return 0;
+}
+
+device_initcall(serial_init);

1.6.2.1