ARM i.MX27: Add devicetree support

This patch adds basic devicetree support for i.MX27 based SoCs.
Only the bindings for which drivers exist are added here:

- UART
- fec
- CSPI
- I2C
- watchdog
- gpio

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
diff --git a/arch/arm/mach-imx/Kconfig b/arch/arm/mach-imx/Kconfig
index 4defb97b..85433b9 100644
--- a/arch/arm/mach-imx/Kconfig
+++ b/arch/arm/mach-imx/Kconfig
@@ -376,6 +376,14 @@
 	  Include support for IMX27 IPCAM platform. This includes specific
 	  configurations for the board and its peripherals.
 
+config MACH_IMX27_DT
+	bool "Support i.MX27 platforms from device tree"
+	select SOC_IMX27
+	select USE_OF
+	help
+	  Include support for Freescale i.MX27 based platforms
+	  using the device tree for discovery
+
 endif
 
 if ARCH_IMX_V6_V7
diff --git a/arch/arm/mach-imx/Makefile b/arch/arm/mach-imx/Makefile
index 55db9c4..4ffeca7 100644
--- a/arch/arm/mach-imx/Makefile
+++ b/arch/arm/mach-imx/Makefile
@@ -41,6 +41,7 @@
 obj-$(CONFIG_MACH_PCA100) += mach-pca100.o
 obj-$(CONFIG_MACH_MXT_TD60) += mach-mxt_td60.o
 obj-$(CONFIG_MACH_IMX27IPCAM) += mach-imx27ipcam.o
+obj-$(CONFIG_MACH_IMX27_DT) += imx27-dt.o
 
 # i.MX31 based machines
 obj-$(CONFIG_MACH_MX31ADS) += mach-mx31ads.o
diff --git a/arch/arm/mach-imx/clock-imx27.c b/arch/arm/mach-imx/clock-imx27.c
index 88fe00a..01ae3a4 100644
--- a/arch/arm/mach-imx/clock-imx27.c
+++ b/arch/arm/mach-imx/clock-imx27.c
@@ -22,6 +22,7 @@
 #include <linux/io.h>
 #include <linux/module.h>
 #include <linux/clkdev.h>
+#include <linux/of.h>
 
 #include <asm/div64.h>
 
@@ -764,3 +765,20 @@
 	return 0;
 }
 
+#ifdef CONFIG_OF
+int __init mx27_clocks_init_dt(void)
+{
+	struct device_node *np;
+	u32 fref = 26000000; /* default */
+
+	for_each_compatible_node(np, NULL, "fixed-clock") {
+		if (!of_device_is_compatible(np, "fsl,imx-osc26m"))
+			continue;
+
+		if (!of_property_read_u32(np, "clock-frequency", &fref))
+			break;
+	}
+
+	return mx27_clocks_init(fref);
+}
+#endif
diff --git a/arch/arm/mach-imx/imx27-dt.c b/arch/arm/mach-imx/imx27-dt.c
new file mode 100644
index 0000000..861ceb8
--- /dev/null
+++ b/arch/arm/mach-imx/imx27-dt.c
@@ -0,0 +1,89 @@
+/*
+ * Copyright 2012 Sascha Hauer, Pengutronix
+ *
+ * The code contained herein is licensed under the GNU General Public
+ * License. You may obtain a copy of the GNU General Public License
+ * Version 2 or later at the following locations:
+ *
+ * http://www.opensource.org/licenses/gpl-license.html
+ * http://www.gnu.org/copyleft/gpl.html
+ */
+
+#include <linux/irq.h>
+#include <linux/irqdomain.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <asm/mach/arch.h>
+#include <asm/mach/time.h>
+#include <mach/common.h>
+#include <mach/mx27.h>
+
+static const struct of_dev_auxdata imx27_auxdata_lookup[] __initconst = {
+	OF_DEV_AUXDATA("fsl,imx27-uart", MX27_UART1_BASE_ADDR, "imx21-uart.0", NULL),
+	OF_DEV_AUXDATA("fsl,imx27-uart", MX27_UART2_BASE_ADDR, "imx21-uart.1", NULL),
+	OF_DEV_AUXDATA("fsl,imx27-uart", MX27_UART3_BASE_ADDR, "imx21-uart.2", NULL),
+	OF_DEV_AUXDATA("fsl,imx27-fec", MX27_FEC_BASE_ADDR, "imx27-fec.0", NULL),
+	OF_DEV_AUXDATA("fsl,imx27-i2c", MX27_I2C1_BASE_ADDR, "imx-i2c.0", NULL),
+	OF_DEV_AUXDATA("fsl,imx27-i2c", MX27_I2C2_BASE_ADDR, "imx-i2c.1", NULL),
+	OF_DEV_AUXDATA("fsl,imx27-cspi", MX27_CSPI1_BASE_ADDR, "imx27-cspi.0", NULL),
+	OF_DEV_AUXDATA("fsl,imx27-cspi", MX27_CSPI2_BASE_ADDR, "imx27-cspi.1", NULL),
+	OF_DEV_AUXDATA("fsl,imx27-cspi", MX27_CSPI3_BASE_ADDR, "imx27-cspi.2", NULL),
+	OF_DEV_AUXDATA("fsl,imx27-wdt", MX27_WDOG_BASE_ADDR, "imx2-wdt.0", NULL),
+	{ /* sentinel */ }
+};
+
+static int __init imx27_avic_add_irq_domain(struct device_node *np,
+				struct device_node *interrupt_parent)
+{
+	irq_domain_add_simple(np, 0);
+	return 0;
+}
+
+static int __init imx27_gpio_add_irq_domain(struct device_node *np,
+				struct device_node *interrupt_parent)
+{
+	static int gpio_irq_base = MXC_GPIO_IRQ_START + ARCH_NR_GPIOS;
+
+	irq_domain_add_simple(np, gpio_irq_base);
+
+	return 0;
+}
+
+static const struct of_device_id imx27_irq_match[] __initconst = {
+	{ .compatible = "fsl,imx27-avic", .data = imx27_avic_add_irq_domain, },
+	{ .compatible = "fsl,imx27-gpio", .data = imx27_gpio_add_irq_domain, },
+	{ /* sentinel */ }
+};
+
+static void __init imx27_dt_init(void)
+{
+	of_irq_init(imx27_irq_match);
+
+	of_platform_populate(NULL, of_default_bus_match_table,
+			     imx27_auxdata_lookup, NULL);
+}
+
+static void __init imx27_timer_init(void)
+{
+	mx27_clocks_init_dt();
+}
+
+static struct sys_timer imx27_timer = {
+	.init = imx27_timer_init,
+};
+
+static const char *imx27_dt_board_compat[] __initdata = {
+	"fsl,imx27",
+	NULL
+};
+
+DT_MACHINE_START(IMX27_DT, "Freescale i.MX27 (Device Tree Support)")
+	.map_io		= mx27_map_io,
+	.init_early	= imx27_init_early,
+	.init_irq	= mx27_init_irq,
+	.handle_irq	= imx27_handle_irq,
+	.timer		= &imx27_timer,
+	.init_machine	= imx27_dt_init,
+	.dt_compat	= imx27_dt_board_compat,
+	.restart	= mxc_restart,
+MACHINE_END