[PATCH v5 6/6] mcpm: exynos: populate suspend and powered_up callbacks
Chander Kashyap
chander.kashyap at linaro.org
Wed May 14 01:03:57 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>
---
Changes in v5:
1. Add comment to address cache access while c-bit is cleared in SCLTR
2. Make exynos_powered_up static
Changes in v4: None
Changes in v3:
1. Removed coherency enablement after suspend failure.
2. Use generic function to poweron cpu.
changes in v2:
1. Fixed typo: enynos_pmu_cpunr to exynos_pmu_cpunr
arch/arm/mach-exynos/mcpm-exynos.c | 34 ++++++++++++++++++++++++++++++++++
1 file changed, 34 insertions(+)
diff --git a/arch/arm/mach-exynos/mcpm-exynos.c b/arch/arm/mach-exynos/mcpm-exynos.c
index c6bb3a4..623dfa7 100644
--- a/arch/arm/mach-exynos/mcpm-exynos.c
+++ b/arch/arm/mach-exynos/mcpm-exynos.c
@@ -253,10 +253,46 @@ static int exynos_power_down_finish(unsigned int cpu, unsigned int cluster)
return -ETIMEDOUT; /* timeout */
}
+static 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(&exynos_mcpm_lock);
+ if (cpu_use_count[cpu][cluster] == 0)
+ cpu_use_count[cpu][cluster] = 1;
+ arch_spin_unlock(&exynos_mcpm_lock);
+}
+
+static void exynos_suspend(u64 residency)
+{
+ unsigned int mpidr, cpunr;
+
+ exynos_power_down();
+
+ /*
+ * Execution reaches here only if cpu did not power down.
+ * Hence roll back the changes done in exynos_power_down function.
+ *
+ * CAUTION: "This function requires the stack data to be visible through
+ * power down and can only be executed on processors like A15 and A7
+ * that hit the cache with the C bit clear in the SCTLR register."
+ */
+ mpidr = read_cpuid_mpidr();
+ cpunr = exynos_pmu_cpunr(mpidr);
+
+ exynos_cpu_power_up(cpunr);
+}
+
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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