ARM: EXYNOS: add exynos_get_boot_addr() helper

Add get_cpu_boot_addr() firmware operation and then
exynos_get_boot_addr() helper.

This is a preparation for adding coupled cpuidle support
for Exynos3250 SoC.

There should be no functional changes caused by this patch.

Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Kukjin Kim <kgene@kernel.org>
diff --git a/arch/arm/mach-exynos/firmware.c b/arch/arm/mach-exynos/firmware.c
index 1bd3576..b30562d 100644
--- a/arch/arm/mach-exynos/firmware.c
+++ b/arch/arm/mach-exynos/firmware.c
@@ -104,6 +104,22 @@
 	return 0;
 }
 
+static int exynos_get_cpu_boot_addr(int cpu, unsigned long *boot_addr)
+{
+	void __iomem *boot_reg;
+
+	if (!sysram_ns_base_addr)
+		return -ENODEV;
+
+	boot_reg = sysram_ns_base_addr + 0x1c;
+
+	if (soc_is_exynos4412())
+		boot_reg += 4 * cpu;
+
+	*boot_addr = __raw_readl(boot_reg);
+	return 0;
+}
+
 static int exynos_cpu_suspend(unsigned long arg)
 {
 	flush_cache_all();
@@ -138,6 +154,7 @@
 static const struct firmware_ops exynos_firmware_ops = {
 	.do_idle		= IS_ENABLED(CONFIG_EXYNOS_CPU_SUSPEND) ? exynos_do_idle : NULL,
 	.set_cpu_boot_addr	= exynos_set_cpu_boot_addr,
+	.get_cpu_boot_addr	= exynos_get_cpu_boot_addr,
 	.cpu_boot		= exynos_cpu_boot,
 	.suspend		= IS_ENABLED(CONFIG_PM_SLEEP) ? exynos_suspend : NULL,
 	.resume			= IS_ENABLED(CONFIG_EXYNOS_CPU_SUSPEND) ? exynos_resume : NULL,