loongson: enable Real Time Clock Support

From 1a13dd55ecc7d3d886cbf39e43acdd0585ca5285 Mon Sep 17 00:00:00 2001
From: Wu Zhangjin <[email protected]>
Date: Sat, 16 May 2009 00:51:39 +0800
Subject: [PATCH 09/30] loongson: enable Real Time Clock Support of fuloong(2e)

by default, RTC_LIB is selected by MIPS, but if RTC_LIB is enabled, Enhanced Real Time Clock Support(RTC) will be disabled, so, to enable it, not select RTC_LIB in LEMOTE_FULOONG2E will fix this problem.

RTC support is needed by some tools like hwclock, if you want hwclock work well, these two jobs need to do:

kernel configuration:

Device Drivers --->
Character devices --->
<*> Enhanced Real Time Clock Support (legacy PC RTC driver)

user-space configuration:

$ mknod /dev/rtc c 10 135

there is another RTC support in linux, whose kernel option is RTC_CLASS, it should be fixed for fuloong(2e) via enabling the binary mode and register the RTC device resource.

to make hwclock work with it normally, please do:

kernel configuration:

Device Drivers --->
<*> Real Time Clock --->

	<*>   PC-style 'CMOS'

user-space configuration:

$ mknod /dev/rtc0 c 254 0

/dev/rtc0 is the default RTC device file.

---
 arch/mips/Kconfig                      |    2 +-
 arch/mips/loongson/fuloong-2e/Makefile |    7 ++++
 arch/mips/loongson/fuloong-2e/rtc.c    |   54
++++++++++++++++++++++++++++++++
 drivers/rtc/rtc-cmos.c                 |    2 +-
 4 files changed, 63 insertions(+), 2 deletions(-)
 create mode 100644 arch/mips/loongson/fuloong-2e/rtc.c

index d9ecb44..974ce41 100644
@@ -6,7 +6,7 @@ config MIPS
 	select HAVE_ARCH_KGDB
 	# Horrible source of confusion.  Die, die, die ...
 	select EMBEDDED
-	select RTC_LIB
+	select RTC_LIB if !LEMOTE_FULOONG2E
 
 mainmenu "Linux/MIPS Kernel Configuration"
 

b/arch/mips/loongson/fuloong-2e/Makefile
index 88002a6..2ab49cb 100644

@@ -10,4 +10,11 @@ obj-y += setup.o init.o cmdline.o time.o reset.o

irq.o \
#
obj-$(CONFIG_EARLY_PRINTK) += early_printk.o

+#
+# Enable RTC Class support
+#
+# please enable CONFIG_RTC_DRV_CMOS
+#
+obj-$(CONFIG_RTC_DRV_CMOS) += rtc.o
+
EXTRA_CFLAGS += -Werror

b/arch/mips/loongson/fuloong-2e/rtc.c
new file mode 100644
index 0000000..c2f413f

@@ -0,0 +1,54 @@
+/*
+ *  Registration of Cobalt RTC platform device.
+ *
+ *  Copyright (C) 2007  Yoichi Yuasa <[email protected]>
+ *  Copyright (C) 2009  Wu Zhangjin <[email protected]>
+ *
+ *  This program is free software; you can redistribute it and/or

modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *

+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA

02110-1301 USA
+ */
+
+#include <linux/init.h>
+#include <linux/ioport.h>
+#include <linux/mc146818rtc.h>
+#include <linux/platform_device.h>
+
+static struct resource rtc_cmos_resource[] = {
+ {
+ .start = RTC_PORT(0),
+ .end = RTC_PORT(1),
+ .flags = IORESOURCE_IO,
+ },
+ {
+ .start = RTC_IRQ,
+ .end = RTC_IRQ,
+ .flags = IORESOURCE_IRQ,
+ },
+};
+
+static struct platform_device rtc_cmos_device = {

+        .name           = "rtc_cmos",
+        .id             = -1,
+        .num_resources  = ARRAY_SIZE(rtc_cmos_resource),
+        .resource       = rtc_cmos_resource

+};
+
+static __init int rtc_cmos_init(void)
+{
+ platform_device_register(&rtc_cmos_device);
+
+ return 0;
+}
+
+device_initcall(rtc_cmos_init);

index b6d35f5..1718526 100644
@@ -757,7 +757,7 @@ cmos_do_probe(struct device *dev, struct resource

*ports, int rtc_irq)
* <asm-generic/rtc.h> doesn't know 12-hour mode either. */
if (is_valid_irq(rtc_irq) &&
- (!(rtc_control & RTC_24H) || (rtc_control & (RTC_DM_BINARY)))) {
+ (!(rtc_control & RTC_24H))) {
dev_dbg(dev, "only 24-hr BCD mode supported\n"); retval = -ENXIO;
goto cleanup1;

1.6.2.1