ARM: EXYNOS: Add support for Exynos secure firmware

Some Exynos-based boards contain secure firmware and must use firmware
operations to set up some hardware.

This patch adds firmware operations for Exynos secure firmware and a way
for board code and device tree to specify that they must be used.

Example of use:

In board code:

  ...MACHINE_START(...)
          /* ... */
          .init_early   = exynos_firmware_init,
          /* ... */
  MACHINE_END

In device tree:

  / {
          /* ... */

          firmware@0203F000 {
                  compatible = "samsung,secure-firmware";
                  reg = <0x0203F000 0x1000>;
          };

          /* ... */
  };
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

Documentation/devicetree/bindings/arm/samsung-boards.txt

@@ -6,3 +6,13 @@ Required root node properties:
     - compatible = should be one or more of the following.
         (a) "samsung,smdkv310" - for Samsung's SMDKV310 eval board.
         (b) "samsung,exynos4210"  - for boards based on Exynos4210 SoC.
+
+Optional:
+    - firmware node, specifying presence and type of secure firmware:
+        - compatible: only "samsung,secure-firmware" is currently supported
+        - reg: address of non-secure SYSRAM used for communication with firmware
+
+	firmware@0203F000 {
+		compatible = "samsung,secure-firmware";
+		reg = <0x0203F000 0x1000>;
+	};

arch/arm/mach-exynos/Makefile

@@ -25,6 +25,7 @@ obj-$(CONFIG_SMP)		+= platsmp.o headsmp.o
 obj-$(CONFIG_HOTPLUG_CPU)	+= hotplug.o
 
 obj-$(CONFIG_ARCH_EXYNOS)	+= exynos-smc.o
+obj-$(CONFIG_ARCH_EXYNOS)	+= firmware.o
 
 plus_sec := $(call as-instr,.arch_extension sec,+sec)
 AFLAGS_exynos-smc.o		:=-Wa,-march=armv7-a$(plus_sec)

arch/arm/mach-exynos/common.h

@@ -30,6 +30,8 @@ void exynos_init_late(void);
 void exynos4_clk_init(struct device_node *np);
 void exynos4_clk_register_fixed_ext(unsigned long, unsigned long);
 
+void exynos_firmware_init(void);
+
 #ifdef CONFIG_PM_GENERIC_DOMAINS
 int exynos_pm_late_initcall(void);
 #else

arch/arm/mach-exynos/firmware.c

+/*
+ * Copyright (C) 2012 Samsung Electronics.
+ * Kyungmin Park <kyungmin.park@samsung.com>
+ * Tomasz Figa <t.figa@samsung.com>
+ *
+ * This program is free software,you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/io.h>
+#include <linux/init.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+
+#include <asm/firmware.h>
+
+#include <mach/map.h>
+
+#include "smc.h"
+
+static int exynos_do_idle(void)
+{
+	exynos_smc(SMC_CMD_SLEEP, 0, 0, 0);
+	return 0;
+}
+
+static int exynos_cpu_boot(int cpu)
+{
+	exynos_smc(SMC_CMD_CPU1BOOT, cpu, 0, 0);
+	return 0;
+}
+
+static int exynos_set_cpu_boot_addr(int cpu, unsigned long boot_addr)
+{
+	void __iomem *boot_reg = S5P_VA_SYSRAM_NS + 0x1c + 4*cpu;
+
+	__raw_writel(boot_addr, boot_reg);
+	return 0;
+}
+
+static const struct firmware_ops exynos_firmware_ops = {
+	.do_idle		= exynos_do_idle,
+	.set_cpu_boot_addr	= exynos_set_cpu_boot_addr,
+	.cpu_boot		= exynos_cpu_boot,
+};
+
+void __init exynos_firmware_init(void)
+{
+	if (of_have_populated_dt()) {
+		struct device_node *nd;
+		const __be32 *addr;
+
+		nd = of_find_compatible_node(NULL, NULL,
+						"samsung,secure-firmware");
+		if (!nd)
+			return;
+
+		addr = of_get_address(nd, 0, NULL, NULL);
+		if (!addr) {
+			pr_err("%s: No address specified.\n", __func__);
+			return;
+		}
+	}
+
+	pr_info("Running under secure firmware.\n");
+
+	register_firmware_ops(&exynos_firmware_ops);
+}

arch/arm/mach-exynos/mach-exynos4-dt.c

@@ -57,6 +57,7 @@ DT_MACHINE_START(EXYNOS4210_DT, "Samsung Exynos4 (Flattened Device Tree)")
 	.smp		= smp_ops(exynos_smp_ops),
 	.init_irq	= exynos4_init_irq,
 	.map_io		= exynos4_dt_map_io,
+	.init_early	= exynos_firmware_init,
 	.init_machine	= exynos4_dt_machine_init,
 	.init_late	= exynos_init_late,
 	.init_time	= exynos_init_time,