1 files changed, 85 insertions, 38 deletions

diff --git a/arch/arm/mach-exynos/mcpm-exynos.c b/arch/arm/mach-exynos/mcpm-exynos.c
index ace0ed617476..b2f8b60cf0e9 100644
--- a/arch/arm/mach-exynos/mcpm-exynos.c
+++ b/arch/arm/mach-exynos/mcpm-exynos.c
@@ -26,6 +26,10 @@
 #define EXYNOS5420_CPUS_PER_CLUSTER	4
 #define EXYNOS5420_NR_CLUSTERS		2
 
+#define EXYNOS5420_ENABLE_AUTOMATIC_CORE_DOWN	BIT(9)
+#define EXYNOS5420_USE_ARM_CORE_DOWN_STATE	BIT(29)
+#define EXYNOS5420_USE_L2_COMMON_UP_STATE	BIT(30)
+
 /*
  * The common v7_exit_coherency_flush API could not be used because of the
  * Erratum 799270 workaround. This macro is the same as the common one (in
@@ -51,7 +55,7 @@
 	"dsb\n\t" \
 	"ldmfd	sp!, {fp, ip}" \
 	: \
-	: "Ir" (S5P_INFORM0) \
+	: "Ir" (pmu_base_addr + S5P_INFORM0) \
 	: "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", \
 	  "r9", "r10", "lr", "memory")
 
@@ -73,36 +77,9 @@ cpu_use_count[EXYNOS5420_CPUS_PER_CLUSTER][EXYNOS5420_NR_CLUSTERS];
 
 #define exynos_cluster_unused(cluster) !exynos_cluster_usecnt(cluster)
 
-static int exynos_cluster_power_control(unsigned int cluster, int enable)
-{
-	unsigned int tries = 100;
-	unsigned int val;
-
-	if (enable) {
-		exynos_cluster_power_up(cluster);
-		val = S5P_CORE_LOCAL_PWR_EN;
-	} else {
-		exynos_cluster_power_down(cluster);
-		val = 0;
-	}
-
-	/* Wait until cluster power control is applied */
-	while (tries--) {
-		if (exynos_cluster_power_state(cluster) == val)
-			return 0;
-
-		cpu_relax();
-	}
-	pr_debug("timed out waiting for cluster %u to power %s\n", cluster,
-		enable ? "on" : "off");
-
-	return -ETIMEDOUT;
-}
-
 static int exynos_power_up(unsigned int cpu, unsigned int cluster)
 {
 	unsigned int cpunr = cpu + (cluster * EXYNOS5420_CPUS_PER_CLUSTER);
-	int err = 0;
 
 	pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
 	if (cpu >= EXYNOS5420_CPUS_PER_CLUSTER ||
@@ -126,12 +103,9 @@ static int exynos_power_up(unsigned int cpu, unsigned int cluster)
 		 * cores.
 		 */
 		if (was_cluster_down)
-			err = exynos_cluster_power_control(cluster, 1);
+			exynos_cluster_power_up(cluster);
 
-		if (!err)
-			exynos_cpu_power_up(cpunr);
-		else
-			exynos_cluster_power_control(cluster, 0);
+		exynos_cpu_power_up(cpunr);
 	} else if (cpu_use_count[cpu][cluster] != 2) {
 		/*
 		 * The only possible values are:
@@ -147,7 +121,7 @@ static int exynos_power_up(unsigned int cpu, unsigned int cluster)
 	arch_spin_unlock(&exynos_mcpm_lock);
 	local_irq_enable();
 
-	return err;
+	return 0;
 }
 
 /*
@@ -178,9 +152,10 @@ static void exynos_power_down(void)
 	if (cpu_use_count[cpu][cluster] == 0) {
 		exynos_cpu_power_down(cpunr);
 
-		if (exynos_cluster_unused(cluster))
-			/* TODO: Turn off the cluster here to save power. */
+		if (exynos_cluster_unused(cluster)) {
+			exynos_cluster_power_down(cluster);
 			last_man = true;
+		}
 	} else if (cpu_use_count[cpu][cluster] == 1) {
 		/*
 		 * A power_up request went ahead of us.
@@ -196,7 +171,7 @@ static void exynos_power_down(void)
 	if (last_man && __mcpm_outbound_enter_critical(cpu, cluster)) {
 		arch_spin_unlock(&exynos_mcpm_lock);
 
-		if (read_cpuid_part_number() == ARM_CPU_PART_CORTEX_A15) {
+		if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A15) {
 			/*
 			 * On the Cortex-A15 we need to disable
 			 * L2 prefetching before flushing the cache.
@@ -257,10 +232,46 @@ static int exynos_wait_for_powerdown(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,
 	.wait_for_powerdown	= exynos_wait_for_powerdown,
+	.suspend		= exynos_suspend,
+	.powered_up		= exynos_powered_up,
 };
 
 static void __init exynos_mcpm_usage_count_init(void)
@@ -289,6 +300,19 @@ static void __naked exynos_pm_power_up_setup(unsigned int affinity_level)
 	"b	cci_enable_port_for_self");
 }
 
+static void __init exynos_cache_off(void)
+{
+	if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A15) {
+		/* disable L2 prefetching on the Cortex-A15 */
+		asm volatile(
+		"mcr	p15, 1, %0, c15, c0, 3\n\t"
+		"isb\n\t"
+		"dsb"
+		: : "r" (0x400));
+	}
+	exynos_v7_exit_coherency_flush(all);
+}
+
 static const struct of_device_id exynos_dt_mcpm_match[] = {
 	{ .compatible = "samsung,exynos5420" },
 	{ .compatible = "samsung,exynos5800" },
@@ -299,6 +323,7 @@ static int __init exynos_mcpm_init(void)
 {
 	struct device_node *node;
 	void __iomem *ns_sram_base_addr;
+	unsigned int value, i;
 	int ret;
 
 	node = of_find_matching_node(NULL, exynos_dt_mcpm_match);
@@ -325,13 +350,15 @@ static int __init exynos_mcpm_init(void)
 	 * To increase the stability of KFC reset we need to program
 	 * the PMU SPARE3 register
 	 */
-	__raw_writel(EXYNOS5420_SWRESET_KFC_SEL, S5P_PMU_SPARE3);
+	pmu_raw_writel(EXYNOS5420_SWRESET_KFC_SEL, S5P_PMU_SPARE3);
 
 	exynos_mcpm_usage_count_init();
 
 	ret = mcpm_platform_register(&exynos_power_ops);
 	if (!ret)
 		ret = mcpm_sync_init(exynos_pm_power_up_setup);
+	if (!ret)
+		ret = mcpm_loopback(exynos_cache_off); /* turn on the CCI */
 	if (ret) {
 		iounmap(ns_sram_base_addr);
 		return ret;
@@ -342,6 +369,26 @@ static int __init exynos_mcpm_init(void)
 	pr_info("Exynos MCPM support installed\n");
 
 	/*
+	 * On Exynos5420/5800 for the A15 and A7 clusters:
+	 *
+	 * EXYNOS5420_ENABLE_AUTOMATIC_CORE_DOWN ensures that all the cores
+	 * in a cluster are turned off before turning off the cluster L2.
+	 *
+	 * EXYNOS5420_USE_ARM_CORE_DOWN_STATE ensures that a cores is powered
+	 * off before waking it up.
+	 *
+	 * EXYNOS5420_USE_L2_COMMON_UP_STATE ensures that cluster L2 will be
+	 * turned on before the first man is powered up.
+	 */
+	for (i = 0; i < EXYNOS5420_NR_CLUSTERS; i++) {
+		value = pmu_raw_readl(EXYNOS_COMMON_OPTION(i));
+		value |= EXYNOS5420_ENABLE_AUTOMATIC_CORE_DOWN |
+			 EXYNOS5420_USE_ARM_CORE_DOWN_STATE    |
+			 EXYNOS5420_USE_L2_COMMON_UP_STATE;
+		pmu_raw_writel(value, EXYNOS_COMMON_OPTION(i));
+	}
+
+	/*
 	 * U-Boot SPL is hardcoded to jump to the start of ns_sram_base_addr
 	 * as part of secondary_cpu_start().  Let's redirect it to the
 	 * mcpm_entry_point().