[Gnewsense-dev] [loongson-PATCH-v1 14/27] enable serial port support of loongson-based machines

[wuzhangjin]

From: Wu Zhangjin <address@hidden>

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,
with this new support, we can remove arch/mips/kernel/8250-platform.c
directly. but in this patch, that file is reserved there for potential
use in the other machines.

Signed-off-by: Wu Zhangjin <address@hidden>
---
 arch/mips/include/asm/mach-loongson/machine.h |    4 ++
 arch/mips/loongson/Kconfig                    |    1 -
 arch/mips/loongson/common/Makefile            |    5 ++
 arch/mips/loongson/common/serial.c            |   64 +++++++++++++++++++++++++
 4 files changed, 73 insertions(+), 1 deletions(-)
 create mode 100644 arch/mips/loongson/common/serial.c

diff --git a/arch/mips/include/asm/mach-loongson/machine.h 
b/arch/mips/include/asm/mach-loongson/machine.h
index bb3dd37..73ff14d 100644
--- a/arch/mips/include/asm/mach-loongson/machine.h
+++ b/arch/mips/include/asm/mach-loongson/machine.h
@@ -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 */
diff --git a/arch/mips/loongson/Kconfig b/arch/mips/loongson/Kconfig
index 2bfda6e..0547907 100644
--- a/arch/mips/loongson/Kconfig
+++ b/arch/mips/loongson/Kconfig
@@ -11,7 +11,6 @@ config LEMOTE_FULOONG2E
        select DMA_NONCOHERENT
        select BOOT_ELF32
        select BOARD_SCACHE
-       select HAVE_STD_PC_SERIAL_PORT
        select HW_HAS_PCI
        select I8259
        select ISA
diff --git a/arch/mips/loongson/common/Makefile 
b/arch/mips/loongson/common/Makefile
index 71a4ea7..06ae7f6 100644
--- a/arch/mips/loongson/common/Makefile
+++ b/arch/mips/loongson/common/Makefile
@@ -23,4 +23,9 @@ obj-$(CONFIG_RTC_DRV_CMOS) += rtc.o
 #
 obj-$(CONFIG_CS5536) += cs5536/
 
+#
+# Enable serial port
+#
+obj-$(CONFIG_SERIAL_8250) += serial.o
+
 EXTRA_CFLAGS += -Werror
diff --git a/arch/mips/loongson/common/serial.c 
b/arch/mips/loongson/common/serial.c
new file mode 100644
index 0000000..335dbe3
--- /dev/null
+++ b/arch/mips/loongson/common/serial.c
@@ -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 (address@hidden)
+ *
+ * Copyright (C) 2009 Lemote, Inc. & Institute of Computing Technology
+ * Author: yanhua (address@hidden)
+ * Author: Wu Zhangjin (address@hidden)
+ */
+
+#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