[PATCH 4/4] mcpm: exynos: populate suspend and powered_up callbacks

Chander Kashyap chander.kashyap at linaro.org
Mon Apr 21 04:49:18 PDT 2014


In order to support cpuidle through mcpm, suspend and powered-up
callbacks are required in mcpm platform code.
Hence populate the same callbacks.

Signed-off-by: Chander Kashyap <chander.kashyap at linaro.org>
Signed-off-by: Chander Kashyap <k.chander at samsung.com>
---
 arch/arm/mach-exynos/mcpm-exynos.c |   53 ++++++++++++++++++++++++++++++++++++
 1 file changed, 53 insertions(+)

diff --git a/arch/arm/mach-exynos/mcpm-exynos.c b/arch/arm/mach-exynos/mcpm-exynos.c
index 46d4968..16af0bd 100644
--- a/arch/arm/mach-exynos/mcpm-exynos.c
+++ b/arch/arm/mach-exynos/mcpm-exynos.c
@@ -318,10 +318,63 @@ static int exynos_power_down_finish(unsigned int cpu, unsigned int cluster)
 	return 0; /* success: the CPU is halted */
 }
 
+static void enable_coherency(void)
+{
+	unsigned long v, u;
+
+	asm volatile(
+		"mrc	p15, 0, %0, c1, c0, 1\n"
+		"orr	%0, %0, %2\n"
+		"ldr	%1, [%3]\n"
+		"and	%1, %1, #0\n"
+		"orr	%0, %0, %1\n"
+		"mcr	p15, 0, %0, c1, c0, 1\n"
+		: "=&r" (v), "=&r" (u)
+		: "Ir" (0x40), "Ir" (S5P_INFORM0)
+		: "cc");
+}
+
+void exynos_powered_up(void)
+{
+	unsigned int mpidr, cpu, cluster;
+
+	mpidr = read_cpuid_mpidr();
+	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
+
+	arch_spin_lock(&bl_lock);
+	if (cpu_use_count[cpu][cluster] == 0)
+		cpu_use_count[cpu][cluster] = 1;
+	arch_spin_unlock(&bl_lock);
+}
+
+static void exynos_suspend(u64 residency)
+{
+	unsigned int mpidr, cpunr;
+
+	mpidr = read_cpuid_mpidr();
+	cpunr = enynos_pmu_cpunr(mpidr);
+
+	__raw_writel(virt_to_phys(mcpm_entry_point), REG_ENTRY_ADDR);
+
+	exynos_power_down();
+
+	/*
+	 * Execution reaches here only if cpu did not power down.
+	 * Hence roll back the changes done in exynos_power_down function.
+	*/
+	__raw_writel(EXYNOS_CORE_LOCAL_PWR_EN,
+			EXYNOS_ARM_CORE_CONFIGURATION(cpunr));
+	set_cr(get_cr() | CR_C);
+	enable_coherency();
+}
+
 static const struct mcpm_platform_ops exynos_power_ops = {
 	.power_up		= exynos_power_up,
 	.power_down		= exynos_power_down,
 	.power_down_finish	= exynos_power_down_finish,
+	.suspend		= exynos_suspend,
+	.powered_up		= exynos_powered_up,
 };
 
 static void __init exynos_mcpm_usage_count_init(void)
-- 
1.7.9.5




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