ARM: clps711x: Add basic DT support

This patch adds basic support to run Cirrus Logic ARMv4T CPUs
with device-tree support.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

arch/arm/mach-clps711x/Kconfig

@@ -2,6 +2,15 @@ if ARCH_CLPS711X
 
 menu "CLPS711X/EP721X/EP731X Implementations"
 
+config MACH_CLPS711X_DT
+	bool "Device-tree support"
+	select CLKSRC_OF
+	select OF_IRQ
+	select USE_OF
+	help
+	  Select this if you want to experiment device-tree with
+	  ARMv4T Cirrus Logic chips.
+
 config ARCH_AUTCPU12
 	bool "AUTCPU12"
 	help

arch/arm/mach-clps711x/Makefile

@@ -6,6 +6,7 @@
 
 obj-y				:= common.o devices.o
 
+obj-$(CONFIG_MACH_CLPS711X_DT)	+= board-dt.o
 obj-$(CONFIG_ARCH_AUTCPU12)	+= board-autcpu12.o
 obj-$(CONFIG_ARCH_CDB89712)	+= board-cdb89712.o
 obj-$(CONFIG_ARCH_CLEP7312)	+= board-clep7312.o

arch/arm/mach-clps711x/board-dt.c

@@ -0,0 +1,82 @@
+/*
+ *  Author: Alexander Shiyan <shc_work@mail.ru>, 2016
+ *
+ * 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/io.h>
+#include <linux/of_fdt.h>
+#include <linux/platform_device.h>
+#include <linux/random.h>
+#include <linux/sizes.h>
+
+#include <linux/mfd/syscon/clps711x.h>
+
+#include <asm/system_info.h>
+#include <asm/system_misc.h>
+#include <asm/mach/arch.h>
+#include <asm/mach/map.h>
+
+#define CLPS711X_VIRT_BASE	IOMEM(0xfeff4000)
+#define CLPS711X_PHYS_BASE	(0x80000000)
+# define SYSFLG1		(0x0140)
+# define HALT			(0x0800)
+# define UNIQID			(0x2440)
+# define RANDID0		(0x2700)
+# define RANDID1		(0x2704)
+# define RANDID2		(0x2708)
+# define RANDID3		(0x270c)
+
+static struct map_desc clps711x_io_desc __initdata = {
+	.virtual	= (unsigned long)CLPS711X_VIRT_BASE,
+	.pfn		= __phys_to_pfn(CLPS711X_PHYS_BASE),
+	.length		= 48 * SZ_1K,
+	.type		= MT_DEVICE,
+};
+
+static void __init clps711x_map_io(void)
+{
+	iotable_init(&clps711x_io_desc, 1);
+}
+
+static const struct resource clps711x_cpuidle_res =
+	DEFINE_RES_MEM(CLPS711X_PHYS_BASE + HALT, SZ_128);
+
+static void __init clps711x_init(void)
+{
+	u32 id[5];
+
+	id[0] = readl(CLPS711X_VIRT_BASE + UNIQID);
+	id[1] = readl(CLPS711X_VIRT_BASE + RANDID0);
+	id[2] = readl(CLPS711X_VIRT_BASE + RANDID1);
+	id[3] = readl(CLPS711X_VIRT_BASE + RANDID2);
+	id[4] = readl(CLPS711X_VIRT_BASE + RANDID3);
+	system_rev = SYSFLG1_VERID(readl(CLPS711X_VIRT_BASE + SYSFLG1));
+
+	add_device_randomness(id, sizeof(id));
+
+	system_serial_low = id[0];
+
+	platform_device_register_simple("clps711x-cpuidle", PLATFORM_DEVID_NONE,
+					&clps711x_cpuidle_res, 1);
+}
+
+static void clps711x_restart(enum reboot_mode mode, const char *cmd)
+{
+	soft_restart(0);
+}
+
+static const char *clps711x_compat[] __initconst = {
+	"cirrus,ep7209",
+	NULL
+};
+
+DT_MACHINE_START(CLPS711X_DT, "Cirrus Logic CLPS711X (Device Tree Support)")
+	.dt_compat	= clps711x_compat,
+	.map_io		= clps711x_map_io,
+	.init_late	= clps711x_init,
+	.restart	= clps711x_restart,
+MACHINE_END