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authorDavid Gibson <dwg@au1.ibm.com>2008-01-11 14:25:34 +1100
committerJosh Boyer <jwboyer@linux.vnet.ibm.com>2008-01-25 07:07:26 -0600
commit22258fa40e54ceefe75a6c6a793f5c44d8339b9c (patch)
tree6a77172e80c134ba4c46889e309d00494e6f8211 /arch
parenta40955167ffc34a1651ebe2e88a8c1db2987fc91 (diff)
[POWERPC] Enable RTC for Ebony and Walnut (v2)
This patch extends the Ebony and Walnut platform code to instantiate the existing ds1742 RTC class driver for the DS1743 RTC/NVRAM chip found on both those boards. The patch uses a helper function to scan the device tree and instantiate the appropriate platform_device based on it, so it should be easy to extend for other boards which have mmio mapped RTC chips. Along with this, the device tree binding for the ds1743 chips is tweaked, based on the existing DS1385 OF binding found at: http://playground.sun.com/1275/proposals/Closed/Remanded/Accepted/346-it.txt Although that document covers the NVRAM portion of the chip, whereas here we're interested in the RTC portion, so it's not entirely clear if that's a good model. This implements only RTC class driver support - that is /dev/rtc0, not /dev/rtc, and the low-level get/set time callbacks remain unimplemented. That means in order to get at the clock you will either need a modified version of hwclock which will look at /dev/rtc0, or you'll need to configure udev to symlink rtc0 to rtc. Signed-off-by: David Gibson <david@gibson.dropbear.id.au> Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Diffstat (limited to 'arch')
-rw-r--r--arch/powerpc/boot/dts/ebony.dts5
-rw-r--r--arch/powerpc/boot/dts/walnut.dts5
-rw-r--r--arch/powerpc/platforms/40x/walnut.c1
-rw-r--r--arch/powerpc/platforms/44x/Kconfig1
-rw-r--r--arch/powerpc/platforms/44x/ebony.c2
-rw-r--r--arch/powerpc/platforms/Kconfig6
-rw-r--r--arch/powerpc/sysdev/Makefile1
-rw-r--r--arch/powerpc/sysdev/of_rtc.c59
8 files changed, 76 insertions, 4 deletions
diff --git a/arch/powerpc/boot/dts/ebony.dts b/arch/powerpc/boot/dts/ebony.dts
index f8790c4747d..7aad135a44b 100644
--- a/arch/powerpc/boot/dts/ebony.dts
+++ b/arch/powerpc/boot/dts/ebony.dts
@@ -158,9 +158,10 @@
};
};
- ds1743@1,0 {
+ nvram@1,0 {
/* NVRAM & RTC */
- compatible = "ds1743";
+ compatible = "ds1743-nvram";
+ #bytes = <2000>;
reg = <1 0 2000>;
};
diff --git a/arch/powerpc/boot/dts/walnut.dts b/arch/powerpc/boot/dts/walnut.dts
index 0e3825e599d..dcc21b0438e 100644
--- a/arch/powerpc/boot/dts/walnut.dts
+++ b/arch/powerpc/boot/dts/walnut.dts
@@ -175,9 +175,10 @@
};
};
- ds1743@1,0 {
+ nvram@1,0 {
/* NVRAM and RTC */
- compatible = "ds1743";
+ compatible = "ds1743-nvram";
+ #bytes = <2000>;
reg = <1 0 2000>;
};
diff --git a/arch/powerpc/platforms/40x/walnut.c b/arch/powerpc/platforms/40x/walnut.c
index f115b6dbf5a..5d9edd917f9 100644
--- a/arch/powerpc/platforms/40x/walnut.c
+++ b/arch/powerpc/platforms/40x/walnut.c
@@ -36,6 +36,7 @@ static __initdata struct of_device_id walnut_of_bus[] = {
static int __init walnut_device_probe(void)
{
of_platform_bus_probe(NULL, walnut_of_bus, NULL);
+ of_instantiate_rtc();
return 0;
}
diff --git a/arch/powerpc/platforms/44x/Kconfig b/arch/powerpc/platforms/44x/Kconfig
index d2480130534..c3e4e8c3c46 100644
--- a/arch/powerpc/platforms/44x/Kconfig
+++ b/arch/powerpc/platforms/44x/Kconfig
@@ -13,6 +13,7 @@ config EBONY
default y
select 440GP
select PCI
+ select OF_RTC
help
This option enables support for the IBM PPC440GP evaluation board.
diff --git a/arch/powerpc/platforms/44x/ebony.c b/arch/powerpc/platforms/44x/ebony.c
index 481a016e153..1a8d467bff8 100644
--- a/arch/powerpc/platforms/44x/ebony.c
+++ b/arch/powerpc/platforms/44x/ebony.c
@@ -18,6 +18,7 @@
#include <linux/init.h>
#include <linux/of_platform.h>
+#include <linux/rtc.h>
#include <asm/machdep.h>
#include <asm/prom.h>
@@ -38,6 +39,7 @@ static __initdata struct of_device_id ebony_of_bus[] = {
static int __init ebony_device_probe(void)
{
of_platform_bus_probe(NULL, ebony_of_bus, NULL);
+ of_instantiate_rtc();
return 0;
}
diff --git a/arch/powerpc/platforms/Kconfig b/arch/powerpc/platforms/Kconfig
index 2cec34314d2..4286664741d 100644
--- a/arch/powerpc/platforms/Kconfig
+++ b/arch/powerpc/platforms/Kconfig
@@ -321,6 +321,12 @@ config FSL_ULI1575
config CPM
bool
+config OF_RTC
+ bool
+ help
+ Uses information from the OF or flattened device tree to instatiate
+ platform devices for direct mapped RTC chips like the DS1742 or DS1743.
+
source "arch/powerpc/sysdev/bestcomm/Kconfig"
endmenu
diff --git a/arch/powerpc/sysdev/Makefile b/arch/powerpc/sysdev/Makefile
index f17e7b885f6..702916bf28f 100644
--- a/arch/powerpc/sysdev/Makefile
+++ b/arch/powerpc/sysdev/Makefile
@@ -28,6 +28,7 @@ obj-$(CONFIG_PPC_I8259) += i8259.o
obj-$(CONFIG_IPIC) += ipic.o
obj-$(CONFIG_4xx) += uic.o
obj-$(CONFIG_XILINX_VIRTEX) += xilinx_intc.o
+obj-$(CONFIG_OF_RTC) += of_rtc.o
ifeq ($(CONFIG_PCI),y)
obj-$(CONFIG_4xx) += ppc4xx_pci.o
endif
diff --git a/arch/powerpc/sysdev/of_rtc.c b/arch/powerpc/sysdev/of_rtc.c
new file mode 100644
index 00000000000..3d54450640c
--- /dev/null
+++ b/arch/powerpc/sysdev/of_rtc.c
@@ -0,0 +1,59 @@
+/*
+ * Instantiate mmio-mapped RTC chips based on device tree information
+ *
+ * Copyright 2007 David Gibson <dwg@au1.ibm.com>, IBM Corporation.
+ *
+ * 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.
+ */
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/init.h>
+#include <linux/of_platform.h>
+
+static __initdata struct {
+ const char *compatible;
+ char *plat_name;
+} of_rtc_table[] = {
+ { "ds1743-nvram", "rtc-ds1742" },
+};
+
+void __init of_instantiate_rtc(void)
+{
+ struct device_node *node;
+ int err;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(of_rtc_table); i++) {
+ char *plat_name = of_rtc_table[i].plat_name;
+
+ for_each_compatible_node(node, NULL,
+ of_rtc_table[i].compatible) {
+ struct resource *res;
+
+ res = kmalloc(sizeof(*res), GFP_KERNEL);
+ if (!res) {
+ printk(KERN_ERR "OF RTC: Out of memory "
+ "allocating resource structure for %s\n",
+ node->full_name);
+ continue;
+ }
+
+ err = of_address_to_resource(node, 0, res);
+ if (err) {
+ printk(KERN_ERR "OF RTC: Error "
+ "translating resources for %s\n",
+ node->full_name);
+ continue;
+ }
+
+ printk(KERN_INFO "OF_RTC: %s is a %s @ 0x%llx-0x%llx\n",
+ node->full_name, plat_name,
+ (unsigned long long)res->start,
+ (unsigned long long)res->end);
+ platform_device_register_simple(plat_name, -1, res, 1);
+ }
+ }
+}