MCPM refactoring and major backend simplification

index 3c165fc2dc..5f8a52ac7e 100644
@@ -55,22 +55,81 @@ bool mcpm_is_available(void)
 	return (platform_ops) ? true : false;
 }
 
+/*
+ * We can't use regular spinlocks. In the switcher case, it is possible
+ * for an outbound CPU to call power_down() after its inbound counterpart
+ * is already live using the same logical CPU number which trips lockdep
+ * debugging.
+ */
+static arch_spinlock_t mcpm_lock = __ARCH_SPIN_LOCK_UNLOCKED;
+
+static int mcpm_cpu_use_count[MAX_NR_CLUSTERS][MAX_CPUS_PER_CLUSTER];
+
+static inline bool mcpm_cluster_unused(unsigned int cluster)
+{
+	int i, cnt;
+	for (i = 0, cnt = 0; i < MAX_CPUS_PER_CLUSTER; i++)
+		cnt |= mcpm_cpu_use_count[cluster][i];
+	return !cnt;
+}
+
 int mcpm_cpu_power_up(unsigned int cpu, unsigned int cluster)
 {
+	bool cpu_is_down, cluster_is_down;
+	int ret = 0;
+
 	if (!platform_ops)
 		return -EUNATCH; /* try not to shadow power_up errors */
 	might_sleep();
-	return platform_ops->power_up(cpu, cluster);
+
+	/* backward compatibility callback */
+	if (platform_ops->power_up)
+		return platform_ops->power_up(cpu, cluster);
+
+	pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
+
+	/*
+	 * Since this is called with IRQs enabled, and no arch_spin_lock_irq
+	 * variant exists, we need to disable IRQs manually here.
+	 */
+	local_irq_disable();
+	arch_spin_lock(&mcpm_lock);
+
+	cpu_is_down = !mcpm_cpu_use_count[cluster][cpu];
+	cluster_is_down = mcpm_cluster_unused(cluster);
+
+	mcpm_cpu_use_count[cluster][cpu]++;
+	/*
+	 * The only possible values are:
+	 * 0 = CPU down
+	 * 1 = CPU (still) up
+	 * 2 = CPU requested to be up before it had a chance
+	 *     to actually make itself down.
+	 * Any other value is a bug.
+	 */
+	BUG_ON(mcpm_cpu_use_count[cluster][cpu] != 1 &&
+	       mcpm_cpu_use_count[cluster][cpu] != 2);
+
+	if (cluster_is_down)
+		ret = platform_ops->cluster_powerup(cluster);
+	if (cpu_is_down && !ret)
+		ret = platform_ops->cpu_powerup(cpu, cluster);
+
+	arch_spin_unlock(&mcpm_lock);
+	local_irq_enable();
+	return ret;
 }
 
 typedef void (*phys_reset_t)(unsigned long);
 
 void mcpm_cpu_power_down(void)
 {
+	unsigned int mpidr, cpu, cluster;
+	bool cpu_going_down, last_man;
 	phys_reset_t phys_reset;
 
-	if (WARN_ON_ONCE(!platform_ops || !platform_ops->power_down))
-		return;
+	if (WARN_ON_ONCE(!platform_ops))
+	       return;
 	BUG_ON(!irqs_disabled());
 
 	/*

@@ -79,28 +138,65 @@ void mcpm_cpu_power_down(void)
 	 */
 	setup_mm_for_reboot();
 
-	platform_ops->power_down();
+	/* backward compatibility callback */
+	if (platform_ops->power_down) {
+		platform_ops->power_down();
+		goto not_dead;
+	}
+
+	mpidr = read_cpuid_mpidr();
+	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
+	pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
+
+	__mcpm_cpu_going_down(cpu, cluster);
 
+	arch_spin_lock(&mcpm_lock);
+	BUG_ON(__mcpm_cluster_state(cluster) != CLUSTER_UP);
+
+	mcpm_cpu_use_count[cluster][cpu]--;
+	BUG_ON(mcpm_cpu_use_count[cluster][cpu] != 0 &&
+	       mcpm_cpu_use_count[cluster][cpu] != 1);
+	cpu_going_down = !mcpm_cpu_use_count[cluster][cpu];
+	last_man = mcpm_cluster_unused(cluster);
+
+	if (last_man && __mcpm_outbound_enter_critical(cpu, cluster)) {
+		platform_ops->cpu_powerdown_prepare(cpu, cluster);
+		platform_ops->cluster_powerdown_prepare(cluster);
+		arch_spin_unlock(&mcpm_lock);
+		platform_ops->cluster_cache_disable();
+		__mcpm_outbound_leave_critical(cluster, CLUSTER_DOWN);
+	} else {
+		if (cpu_going_down)
+			platform_ops->cpu_powerdown_prepare(cpu, cluster);
+		arch_spin_unlock(&mcpm_lock);
+		/*
+		 * If cpu_going_down is false here, that means a power_up
+		 * request raced ahead of us.  Even if we do not want to
+		 * shut this CPU down, the caller still expects execution
+		 * to return through the system resume entry path, like
+		 * when the WFI is aborted due to a new IRQ or the like..
+		 * So let's continue with cache cleaning in all cases.
+		 */
+		platform_ops->cpu_cache_disable();
+	}
+
+	__mcpm_cpu_down(cpu, cluster);
+
+	/* Now we are prepared for power-down, do it: */
+	if (cpu_going_down)
+		wfi();
+
+not_dead:
 	/*
 	 * It is possible for a power_up request to happen concurrently
 	 * with a power_down request for the same CPU. In this case the
-	 * power_down method might not be able to actually enter a
-	 * powered down state with the WFI instruction if the power_up
-	 * method has removed the required reset condition.  The
-	 * power_down method is then allowed to return. We must perform
-	 * a re-entry in the kernel as if the power_up method just had
-	 * deasserted reset on the CPU.
-	 *
-	 * To simplify race issues, the platform specific implementation
-	 * must accommodate for the possibility of unordered calls to
-	 * power_down and power_up with a usage count. Therefore, if a
-	 * call to power_up is issued for a CPU that is not down, then
-	 * the next call to power_down must not attempt a full shutdown
-	 * but only do the minimum (normally disabling L1 cache and CPU
-	 * coherency) and return just as if a concurrent power_up request
-	 * had happened as described above.
+	 * CPU might not be able to actually enter a powered down state
+	 * with the WFI instruction if the power_up request has removed
+	 * the required reset condition.  We must perform a re-entry in
+	 * the kernel as if the power_up method just had deasserted reset
+	 * on the CPU.
 	 */
-
 	phys_reset = (phys_reset_t)(unsigned long)virt_to_phys(cpu_reset);
 	phys_reset(virt_to_phys(mcpm_entry_point));
 

@@ -125,26 +221,66 @@ int mcpm_wait_for_cpu_powerdown(unsigned int cpu, unsigned int cluster)
 
 void mcpm_cpu_suspend(u64 expected_residency)
 {
-	phys_reset_t phys_reset;
-
-	if (WARN_ON_ONCE(!platform_ops || !platform_ops->suspend))
+	if (WARN_ON_ONCE(!platform_ops))
 		return;
-	BUG_ON(!irqs_disabled());
 
-	/* Very similar to mcpm_cpu_power_down() */
-	setup_mm_for_reboot();
-	platform_ops->suspend(expected_residency);
-	phys_reset = (phys_reset_t)(unsigned long)virt_to_phys(cpu_reset);
-	phys_reset(virt_to_phys(mcpm_entry_point));
-	BUG();
+	/* backward compatibility callback */
+	if (platform_ops->suspend) {
+		phys_reset_t phys_reset;
+		BUG_ON(!irqs_disabled());
+		setup_mm_for_reboot();
+		platform_ops->suspend(expected_residency);
+		phys_reset = (phys_reset_t)(unsigned long)virt_to_phys(cpu_reset);
+		phys_reset(virt_to_phys(mcpm_entry_point));
+		BUG();
+	}
+
+	/* Some platforms might have to enable special resume modes, etc. */
+	if (platform_ops->cpu_suspend_prepare) {
+		unsigned int mpidr = read_cpuid_mpidr();
+		unsigned int cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+		unsigned int cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1); 
+		arch_spin_lock(&mcpm_lock);
+		platform_ops->cpu_suspend_prepare(cpu, cluster);
+		arch_spin_unlock(&mcpm_lock);
+	}
+	mcpm_cpu_power_down();
 }
 
 int mcpm_cpu_powered_up(void)
 {
+	unsigned int mpidr, cpu, cluster;
+	bool cpu_was_down, first_man;
+	unsigned long flags;
+
 	if (!platform_ops)
 		return -EUNATCH;
-	if (platform_ops->powered_up)
+
+	/* backward compatibility callback */
+	if (platform_ops->powered_up) {
 		platform_ops->powered_up();
+		return 0;
+	}
+
+	mpidr = read_cpuid_mpidr();
+	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
+	local_irq_save(flags);
+	arch_spin_lock(&mcpm_lock);
+
+	cpu_was_down = !mcpm_cpu_use_count[cluster][cpu];
+	first_man = mcpm_cluster_unused(cluster);
+
+	if (first_man && platform_ops->cluster_is_up)
+		platform_ops->cluster_is_up(cluster);
+	if (cpu_was_down)
+		mcpm_cpu_use_count[cluster][cpu] = 1;
+	if (platform_ops->cpu_is_up)
+		platform_ops->cpu_is_up(cpu, cluster);
+
+	arch_spin_unlock(&mcpm_lock);
+	local_irq_restore(flags);
+
 	return 0;
 }
 

@@ -334,8 +470,10 @@ int __init mcpm_sync_init(
 	}
 	mpidr = read_cpuid_mpidr();
 	this_cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
-	for_each_online_cpu(i)
+	for_each_online_cpu(i) {
+		mcpm_cpu_use_count[this_cluster][i] = 1;
 		mcpm_sync.clusters[this_cluster].cpus[i].cpu = CPU_UP;
+	}
 	mcpm_sync.clusters[this_cluster].cluster = CLUSTER_UP;
 	sync_cache_w(&mcpm_sync);
 

75 lines not on this page · raw message

index 2fb78b4648..b3328cd46c 100644
@@ -18,7 +18,6 @@
 #include <linux/kernel.h>
 #include <linux/of_address.h>
 #include <linux/of_irq.h>
-#include <linux/spinlock.h>
 #include <linux/errno.h>
 #include <linux/irqchip/arm-gic.h>
 

@@ -44,101 +43,36 @@
 
 static void __iomem *scc;
 
-/*
- * We can't use regular spinlocks. In the switcher case, it is possible
- * for an outbound CPU to call power_down() after its inbound counterpart
- * is already live using the same logical CPU number which trips lockdep
- * debugging.
- */
-static arch_spinlock_t tc2_pm_lock = __ARCH_SPIN_LOCK_UNLOCKED;
-
 #define TC2_CLUSTERS			2
 #define TC2_MAX_CPUS_PER_CLUSTER	3
 
 static unsigned int tc2_nr_cpus[TC2_CLUSTERS];
 
-/* Keep per-cpu usage count to cope with unordered up/down requests */
-static int tc2_pm_use_count[TC2_MAX_CPUS_PER_CLUSTER][TC2_CLUSTERS];
-
-#define tc2_cluster_unused(cluster) \
-	(!tc2_pm_use_count[0][cluster] && \
-	 !tc2_pm_use_count[1][cluster] && \
-	 !tc2_pm_use_count[2][cluster])
-
-static int tc2_pm_power_up(unsigned int cpu, unsigned int cluster)
+static int tc2_pm_cpu_powerup(unsigned int cpu, unsigned int cluster)
 {
 	pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
 	if (cluster >= TC2_CLUSTERS || cpu >= tc2_nr_cpus[cluster])
 		return -EINVAL;
-
-	/*
-	 * Since this is called with IRQs enabled, and no arch_spin_lock_irq
-	 * variant exists, we need to disable IRQs manually here.
-	 */
-	local_irq_disable();
-	arch_spin_lock(&tc2_pm_lock);
-
-	if (tc2_cluster_unused(cluster))
-		ve_spc_powerdown(cluster, false);
-
-	tc2_pm_use_count[cpu][cluster]++;
-	if (tc2_pm_use_count[cpu][cluster] == 1) {
-		ve_spc_set_resume_addr(cluster, cpu,
-				       virt_to_phys(mcpm_entry_point));
-		ve_spc_cpu_wakeup_irq(cluster, cpu, true);
-	} else if (tc2_pm_use_count[cpu][cluster] != 2) {
-		/*
-		 * The only possible values are:
-		 * 0 = CPU down
-		 * 1 = CPU (still) up
-		 * 2 = CPU requested to be up before it had a chance
-		 *     to actually make itself down.
-		 * Any other value is a bug.
-		 */
-		BUG();
-	}
-
-	arch_spin_unlock(&tc2_pm_lock);
-	local_irq_enable();
-
+	ve_spc_set_resume_addr(cluster, cpu,
+			       virt_to_phys(mcpm_entry_point));
+	ve_spc_cpu_wakeup_irq(cluster, cpu, true);
 	return 0;
 }
 
-static void tc2_pm_down(u64 residency)
+static int tc2_pm_cluster_powerup(unsigned int cluster)
 {
-	unsigned int mpidr, cpu, cluster;
-	bool last_man = false, skip_wfi = false;
-
-	mpidr = read_cpuid_mpidr();
-	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
-	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
+	pr_debug("%s: cluster %u\n", __func__, cluster);
+	if (cluster >= TC2_CLUSTERS)
+		return -EINVAL;
+	ve_spc_powerdown(cluster, false);
+	return 0;
+}
 
+static void tc2_pm_cpu_powerdown_prepare(unsigned int cpu, unsigned int cluster)
+{
 	pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
 	BUG_ON(cluster >= TC2_CLUSTERS || cpu >= TC2_MAX_CPUS_PER_CLUSTER);
-
-	__mcpm_cpu_going_down(cpu, cluster);
-
-	arch_spin_lock(&tc2_pm_lock);
-	BUG_ON(__mcpm_cluster_state(cluster) != CLUSTER_UP);
-	tc2_pm_use_count[cpu][cluster]--;
-	if (tc2_pm_use_count[cpu][cluster] == 0) {
-		ve_spc_cpu_wakeup_irq(cluster, cpu, true);
-		if (tc2_cluster_unused(cluster)) {
-			ve_spc_powerdown(cluster, true);
-			ve_spc_global_wakeup_irq(true);
-			last_man = true;
-		}
-	} else if (tc2_pm_use_count[cpu][cluster] == 1) {
-		/*
-		 * A power_up request went ahead of us.
-		 * Even if we do not want to shut this CPU down,
-		 * the caller expects a certain state as if the WFI
-		 * was aborted.  So let's continue with cache cleaning.
-		 */
-		skip_wfi = true;
-	} else
-		BUG();
-
+	ve_spc_cpu_wakeup_irq(cluster, cpu, true);
 	/*
 	 * If the CPU is committed to power down, make sure
 	 * the power controller will be in charge of waking it

@@ -146,55 +80,38 @@ static void tc2_pm_down(u64 residency)
 	 * to the CPU by disabling the GIC CPU IF to prevent wfi
 	 * from completing execution behind power controller back
 	 */
-	if (!skip_wfi)
-		gic_cpu_if_down();
-
-	if (last_man && __mcpm_outbound_enter_critical(cpu, cluster)) {
-		arch_spin_unlock(&tc2_pm_lock);
-
-		if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A15) {
-			/*
-			 * On the Cortex-A15 we need to disable
-			 * L2 prefetching before flushing the cache.
-			 */
-			asm volatile(
-			"mcr	p15, 1, %0, c15, c0, 3 \n\t"
-			"isb	\n\t"
-			"dsb	"
-			: : "r" (0x400) );
-		}
-
-		v7_exit_coherency_flush(all);
-
-		cci_disable_port_by_cpu(mpidr);
-
-		__mcpm_outbound_leave_critical(cluster, CLUSTER_DOWN);
-	} else {
-		/*
-		 * If last man then undo any setup done previously.
-		 */
-		if (last_man) {
-			ve_spc_powerdown(cluster, false);
-			ve_spc_global_wakeup_irq(false);
-		}
-
-		arch_spin_unlock(&tc2_pm_lock);
-
-		v7_exit_coherency_flush(louis);
-	}
-
-	__mcpm_cpu_down(cpu, cluster);
+	gic_cpu_if_down();
+}
 
-	/* Now we are prepared for power-down, do it: */
-	if (!skip_wfi)
-		wfi();
+static void tc2_pm_cluster_powerdown_prepare(unsigned int cluster)
+{
+	pr_debug("%s: cluster %u\n", __func__, cluster);
+	BUG_ON(cluster >= TC2_CLUSTERS);
+	ve_spc_powerdown(cluster, true);
+	ve_spc_global_wakeup_irq(true);
+}
 
-	/* Not dead at this point?  Let our caller cope. */
+static void tc2_pm_cpu_cache_disable(void)
+{
+	v7_exit_coherency_flush(louis);
 }
 
-static void tc2_pm_power_down(void)
+static void tc2_pm_cluster_cache_disable(void)
 {
-	tc2_pm_down(0);
+	if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A15) {
+		/*
+		 * On the Cortex-A15 we need to disable
+		 * L2 prefetching before flushing the cache.
+		 */
+		asm volatile(
+		"mcr	p15, 1, %0, c15, c0, 3 \n\t"
+		"isb	\n\t"
+		"dsb	"
+		: : "r" (0x400) );
+	}
+
+	v7_exit_coherency_flush(all);
+	cci_disable_port_by_cpu(read_cpuid_mpidr());
 }
 
 static int tc2_core_in_reset(unsigned int cpu, unsigned int cluster)

@@ -217,27 +134,21 @@ static int tc2_pm_wait_for_powerdown(unsigned int cpu, unsigned int cluster)
 	BUG_ON(cluster >= TC2_CLUSTERS || cpu >= TC2_MAX_CPUS_PER_CLUSTER);
 
 	for (tries = 0; tries < TIMEOUT_MSEC / POLL_MSEC; ++tries) {
+		pr_debug("%s(cpu=%u, cluster=%u): RESET_CTRL = 0x%08X\n",
+			 __func__, cpu, cluster,
+			 readl_relaxed(scc + RESET_CTRL));
+
 		/*
-		 * Only examine the hardware state if the target CPU has
-		 * caught up@least as far as tc2_pm_down():
+		 * We need the CPU to reach WFI, but the power
+		 * controller may put the cluster in reset and
+		 * power it off as soon as that happens, before
+		 * we have a chance to see STANDBYWFI.
+		 *
+		 * So we need to check for both conditions:
 		 */
-		if (ACCESS_ONCE(tc2_pm_use_count[cpu][cluster]) == 0) {
-			pr_debug("%s(cpu=%u, cluster=%u): RESET_CTRL = 0x%08X\n",
-				 __func__, cpu, cluster,
-				 readl_relaxed(scc + RESET_CTRL));
-
-			/*
-			 * We need the CPU to reach WFI, but the power
-			 * controller may put the cluster in reset and
-			 * power it off as soon as that happens, before
-			 * we have a chance to see STANDBYWFI.
-			 *
-			 * So we need to check for both conditions:
-			 */
-			if (tc2_core_in_reset(cpu, cluster) ||
-			    ve_spc_cpu_in_wfi(cpu, cluster))
-				return 0; /* success: the CPU is halted */
-		}
+		if (tc2_core_in_reset(cpu, cluster) ||
+		    ve_spc_cpu_in_wfi(cpu, cluster))
+			return 0; /* success: the CPU is halted */
 
 		/* Otherwise, wait and retry: */
 		msleep(POLL_MSEC);

@@ -246,72 +157,40 @@ static int tc2_pm_wait_for_powerdown(unsigned int cpu, unsigned int cluster)
 	return -ETIMEDOUT; /* timeout */
 }
 
-static void tc2_pm_suspend(u64 residency)
+static void tc2_pm_cpu_suspend_prepare(unsigned int cpu, unsigned int cluster)
 {
-	unsigned int mpidr, cpu, cluster;
-
-	mpidr = read_cpuid_mpidr();
-	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
-	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
 	ve_spc_set_resume_addr(cluster, cpu, virt_to_phys(mcpm_entry_point));
-	tc2_pm_down(residency);
 }
 
-static void tc2_pm_powered_up(void)
+static void tc2_pm_cpu_is_up(unsigned int cpu, unsigned int cluster)
 {
-	unsigned int mpidr, cpu, cluster;
-	unsigned long flags;
-
-	mpidr = read_cpuid_mpidr();
-	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
-	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
-
 	pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
 	BUG_ON(cluster >= TC2_CLUSTERS || cpu >= TC2_MAX_CPUS_PER_CLUSTER);
-
-	local_irq_save(flags);
-	arch_spin_lock(&tc2_pm_lock);
-
-	if (tc2_cluster_unused(cluster)) {
-		ve_spc_powerdown(cluster, false);
-		ve_spc_global_wakeup_irq(false);
-	}
-
-	if (!tc2_pm_use_count[cpu][cluster])
-		tc2_pm_use_count[cpu][cluster] = 1;
-
 	ve_spc_cpu_wakeup_irq(cluster, cpu, false);
 	ve_spc_set_resume_addr(cluster, cpu, 0);
+}
 
-	arch_spin_unlock(&tc2_pm_lock);
-	local_irq_restore(flags);
+static void tc2_pm_cluster_is_up(unsigned int cluster)
+{
+	pr_debug("%s: cluster %u\n", __func__, cluster);
+	BUG_ON(cluster >= TC2_CLUSTERS);
+	ve_spc_powerdown(cluster, false);
+	ve_spc_global_wakeup_irq(false);
 }
 
 static const struct mcpm_platform_ops tc2_pm_power_ops = {
-	.power_up		= tc2_pm_power_up,
-	.power_down		= tc2_pm_power_down,
+	.cpu_powerup		= tc2_pm_cpu_powerup,
+	.cluster_powerup	= tc2_pm_cluster_powerup,
+	.cpu_suspend_prepare	= tc2_pm_cpu_suspend_prepare,
+	.cpu_powerdown_prepare	= tc2_pm_cpu_powerdown_prepare,
+	.cluster_powerdown_prepare = tc2_pm_cluster_powerdown_prepare,
+	.cpu_cache_disable	= tc2_pm_cpu_cache_disable,
+	.cluster_cache_disable	= tc2_pm_cluster_cache_disable,
 	.wait_for_powerdown	= tc2_pm_wait_for_powerdown,
-	.suspend		= tc2_pm_suspend,
-	.powered_up		= tc2_pm_powered_up,
+	.cpu_is_up		= tc2_pm_cpu_is_up,
+	.cluster_is_up		= tc2_pm_cluster_is_up,
 };
 
-static bool __init tc2_pm_usage_count_init(void)
-{
-	unsigned int mpidr, cpu, cluster;
-
-	mpidr = read_cpuid_mpidr();
-	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
-	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
-
-	pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
-	if (cluster >= TC2_CLUSTERS || cpu >= tc2_nr_cpus[cluster]) {
-		pr_err("%s: boot CPU is out of bound!\n", __func__);
-		return false;
-	}
-	tc2_pm_use_count[cpu][cluster] = 1;
-	return true;
-}
-
 /*
  * Enable cluster-level coherency, in preparation for turning on the MMU.
  */

@@ -323,23 +202,9 @@ static void __naked tc2_pm_power_up_setup(unsigned int affinity_level)
 "	b	cci_enable_port_for_self ");
 }
 
-static void __init tc2_cache_off(void)
-{
-	pr_info("TC2: disabling cache during MCPM loopback test\n");
-	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) );
-	}
-	v7_exit_coherency_flush(all);
-	cci_disable_port_by_cpu(read_cpuid_mpidr());
-}
-
 static int __init tc2_pm_init(void)
 {
+	unsigned int mpidr, cpu, cluster;
 	int ret, irq;
 	u32 a15_cluster_id, a7_cluster_id, sys_info;
 	struct device_node *np;

@@ -379,14 +244,20 @@ static int __init tc2_pm_init(void)
 	if (!cci_probed())
 		return -ENODEV;
 
-	if (!tc2_pm_usage_count_init())
+	mpidr = read_cpuid_mpidr();
+	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
+	pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
+	if (cluster >= TC2_CLUSTERS || cpu >= tc2_nr_cpus[cluster]) {
+		pr_err("%s: boot CPU is out of bound!\n", __func__);
 		return -EINVAL;
+	}
 
 	ret = mcpm_platform_register(&tc2_pm_power_ops);
 	if (!ret) {
 		mcpm_sync_init(tc2_pm_power_up_setup);
 		/* test if we can (re)enable the CCI on our own */
-		BUG_ON(mcpm_loopback(tc2_cache_off) != 0);
+		BUG_ON(mcpm_loopback(tc2_pm_cluster_cache_disable) != 0);
 		pr_info("TC2 power management initialized\n");
 	}
 	return ret;

index 30b993399e..12c74734cd 100644
@@ -54,7 +54,7 @@ static int dcscb_power_up(unsigned int cpu, unsigned int cluster)
 	unsigned int all_mask;
 
 	pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
-	if (cpu >= 4 || cluster >= 2)
+	if (cluster >= 2 || !(cpumask & dcscb_allcpus_mask[cluster]))
 		return -EINVAL;
 
 	all_mask = dcscb_allcpus_mask[cluster];

@@ -105,7 +105,7 @@ static void dcscb_power_down(void)
 	cpumask = (1 << cpu);
 
 	pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
-	BUG_ON(cpu >= 4 || cluster >= 2);
+	BUG_ON(cluster >= 2 || !(cpumask & dcscb_allcpus_mask[cluster]));
 
 	all_mask = dcscb_allcpus_mask[cluster];
 

@@ -189,7 +189,7 @@ static void __init dcscb_usage_count_init(void)
 	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
 
 	pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
-	BUG_ON(cpu >= 4 || cluster >= 2);
+	BUG_ON(cluster >= 2 || !((1 << cpu) & dcscb_allcpus_mask[cluster]));
 	dcscb_use_count[cpu][cluster] = 1;
 }
 

index 12c74734cd..5cedcf5721 100644
@@ -12,7 +12,6 @@
 #include <linux/init.h>
 #include <linux/kernel.h>
 #include <linux/io.h>
-#include <linux/spinlock.h>
 #include <linux/errno.h>
 #include <linux/of_address.h>
 #include <linux/vexpress.h>

@@ -36,163 +35,102 @@
 #define KFC_CFG_W	0x2c
 #define DCS_CFG_R	0x30
 
-/*
- * We can't use regular spinlocks. In the switcher case, it is possible
- * for an outbound CPU to call power_down() while its inbound counterpart
- * is already live using the same logical CPU number which trips lockdep
- * debugging.
- */
-static arch_spinlock_t dcscb_lock = __ARCH_SPIN_LOCK_UNLOCKED;
-
 static void __iomem *dcscb_base;
-static int dcscb_use_count[4][2];
 static int dcscb_allcpus_mask[2];
 
-static int dcscb_power_up(unsigned int cpu, unsigned int cluster)
+static int dcscb_cpu_powerup(unsigned int cpu, unsigned int cluster)
 {
 	unsigned int rst_hold, cpumask = (1 << cpu);
-	unsigned int all_mask;
 
 	pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
 	if (cluster >= 2 || !(cpumask & dcscb_allcpus_mask[cluster]))
 		return -EINVAL;
 
-	all_mask = dcscb_allcpus_mask[cluster];
+	rst_hold = readl_relaxed(dcscb_base + RST_HOLD0 + cluster * 4);
+	rst_hold &= ~(cpumask | (cpumask << 4));
+	writel_relaxed(rst_hold, dcscb_base + RST_HOLD0 + cluster * 4);
+	return 0;
+}
 
-	/*
-	 * Since this is called with IRQs enabled, and no arch_spin_lock_irq
-	 * variant exists, we need to disable IRQs manually here.
-	 */
-	local_irq_disable();
-	arch_spin_lock(&dcscb_lock);
-
-	dcscb_use_count[cpu][cluster]++;
-	if (dcscb_use_count[cpu][cluster] == 1) {
-		rst_hold = readl_relaxed(dcscb_base + RST_HOLD0 + cluster * 4);
-		if (rst_hold & (1 << 8)) {
-			/* remove cluster reset and add individual CPU's reset */
-			rst_hold &= ~(1 << 8);
-			rst_hold |= all_mask;
-		}
-		rst_hold &= ~(cpumask | (cpumask << 4));
-		writel_relaxed(rst_hold, dcscb_base + RST_HOLD0 + cluster * 4);
-	} else if (dcscb_use_count[cpu][cluster] != 2) {
-		/*
-		 * The only possible values are:
-		 * 0 = CPU down
-		 * 1 = CPU (still) up
-		 * 2 = CPU requested to be up before it had a chance
-		 *     to actually make itself down.
-		 * Any other value is a bug.
-		 */
-		BUG();
-	}
+static int dcscb_cluster_powerup(unsigned int cluster)
+{
+	unsigned int rst_hold;
 
-	arch_spin_unlock(&dcscb_lock);
-	local_irq_enable();
+	pr_debug("%s: cluster %u\n", __func__, cluster);
+	if (cluster >= 2)
+		return -EINVAL;
 
+	/* remove cluster reset and add individual CPU's reset */
+	rst_hold = readl_relaxed(dcscb_base + RST_HOLD0 + cluster * 4);
+	rst_hold &= ~(1 << 8);
+	rst_hold |= dcscb_allcpus_mask[cluster];
+	writel_relaxed(rst_hold, dcscb_base + RST_HOLD0 + cluster * 4);
 	return 0;
 }
 
-static void dcscb_power_down(void)
+static void dcscb_cpu_powerdown_prepare(unsigned int cpu, unsigned int cluster)
 {
-	unsigned int mpidr, cpu, cluster, rst_hold, cpumask, all_mask;
-	bool last_man = false, skip_wfi = false;
-
-	mpidr = read_cpuid_mpidr();
-	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
-	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
-	cpumask = (1 << cpu);
+	unsigned int rst_hold;
 
 	pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
-	BUG_ON(cluster >= 2 || !(cpumask & dcscb_allcpus_mask[cluster]));
-
-	all_mask = dcscb_allcpus_mask[cluster];
-
-	__mcpm_cpu_going_down(cpu, cluster);
-
-	arch_spin_lock(&dcscb_lock);
-	BUG_ON(__mcpm_cluster_state(cluster) != CLUSTER_UP);
-	dcscb_use_count[cpu][cluster]--;
-	if (dcscb_use_count[cpu][cluster] == 0) {
-		rst_hold = readl_relaxed(dcscb_base + RST_HOLD0 + cluster * 4);
-		rst_hold |= cpumask;
-		if (((rst_hold | (rst_hold >> 4)) & all_mask) == all_mask) {
-			rst_hold |= (1 << 8);
-			last_man = true;
-		}
-		writel_relaxed(rst_hold, dcscb_base + RST_HOLD0 + cluster * 4);
-	} else if (dcscb_use_count[cpu][cluster] == 1) {
-		/*
-		 * A power_up request went ahead of us.
-		 * Even if we do not want to shut this CPU down,
-		 * the caller expects a certain state as if the WFI
-		 * was aborted.  So let's continue with cache cleaning.
-		 */
-		skip_wfi = true;
-	} else
-		BUG();
-
-	if (last_man && __mcpm_outbound_enter_critical(cpu, cluster)) {
-		arch_spin_unlock(&dcscb_lock);
-
-		/* Flush all cache levels for this cluster. */
-		v7_exit_coherency_flush(all);
-
-		/*
-		 * A full outer cache flush could be needed@this point
-		 * on platforms with such a cache, depending on where the
-		 * outer cache sits. In some cases the notion of a "last
-		 * cluster standing" would need to be implemented if the
-		 * outer cache is shared across clusters. In any case, when
-		 * the outer cache needs flushing, there is no concurrent
-		 * access to the cache controller to worry about and no
-		 * special locking besides what is already provided by the
-		 * MCPM state machinery is needed.
-		 */
-
-		/*
-		 * Disable cluster-level coherency by masking
-		 * incoming snoops and DVM messages:
-		 */
-		cci_disable_port_by_cpu(mpidr);
-
-		__mcpm_outbound_leave_critical(cluster, CLUSTER_DOWN);
-	} else {
-		arch_spin_unlock(&dcscb_lock);
-
-		/* Disable and flush the local CPU cache. */
-		v7_exit_coherency_flush(louis);
-	}
+	BUG_ON(cluster >= 2 || !((1 << cpu) & dcscb_allcpus_mask[cluster]));
 
-	__mcpm_cpu_down(cpu, cluster);
+	rst_hold = readl_relaxed(dcscb_base + RST_HOLD0 + cluster * 4);
+	rst_hold |= (1 << cpu);
+	writel_relaxed(rst_hold, dcscb_base + RST_HOLD0 + cluster * 4);
+}
 
-	/* Now we are prepared for power-down, do it: */
-	dsb();
-	if (!skip_wfi)
-		wfi();
+static void dcscb_cluster_powerdown_prepare(unsigned int cluster)
+{
+	unsigned int rst_hold;
 
-	/* Not dead@this point?  Let our caller cope. */
+	pr_debug("%s: cluster %u\n", __func__, cluster);
+	BUG_ON(cluster >= 2);
+
+	rst_hold = readl_relaxed(dcscb_base + RST_HOLD0 + cluster * 4);
+	rst_hold |= (1 << 8);
+	writel_relaxed(rst_hold, dcscb_base + RST_HOLD0 + cluster * 4);
 }
 
-static const struct mcpm_platform_ops dcscb_power_ops = {
-	.power_up	= dcscb_power_up,
-	.power_down	= dcscb_power_down,
-};
+static void dcscb_cpu_cache_disable(void)
+{
+	/* Disable and flush the local CPU cache. */
+	v7_exit_coherency_flush(louis);
+}
 
-static void __init dcscb_usage_count_init(void)
+static void dcscb_cluster_cache_disable(void)
 {
-	unsigned int mpidr, cpu, cluster;
+	/* Flush all cache levels for this cluster. */
+	v7_exit_coherency_flush(all);
 
-	mpidr = read_cpuid_mpidr();
-	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
-	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
+	/*
+	 * A full outer cache flush could be needed@this point
+	 * on platforms with such a cache, depending on where the
+	 * outer cache sits. In some cases the notion of a "last
+	 * cluster standing" would need to be implemented if the
+	 * outer cache is shared across clusters. In any case, when
+	 * the outer cache needs flushing, there is no concurrent
+	 * access to the cache controller to worry about and no
+	 * special locking besides what is already provided by the
+	 * MCPM state machinery is needed.
+	 */
 
-	pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
-	BUG_ON(cluster >= 2 || !((1 << cpu) & dcscb_allcpus_mask[cluster]));
-	dcscb_use_count[cpu][cluster] = 1;
+	/*
+	 * Disable cluster-level coherency by masking
+	 * incoming snoops and DVM messages:
+	 */
+	cci_disable_port_by_cpu(read_cpuid_mpidr());
 }
 
+static const struct mcpm_platform_ops dcscb_power_ops = {
+	.cpu_powerup		= dcscb_cpu_powerup,
+	.cluster_powerup	= dcscb_cluster_powerup,
+	.cpu_powerdown_prepare	= dcscb_cpu_powerdown_prepare,
+	.cluster_powerdown_prepare = dcscb_cluster_powerdown_prepare,
+	.cpu_cache_disable	= dcscb_cpu_cache_disable,
+	.cluster_cache_disable	= dcscb_cluster_cache_disable,
+};
+
 extern void dcscb_power_up_setup(unsigned int affinity_level);
 
 static int __init dcscb_init(void)

@@ -213,7 +151,6 @@ static int __init dcscb_init(void)
 	cfg = readl_relaxed(dcscb_base + DCS_CFG_R);
 	dcscb_allcpus_mask[0] = (1 << (((cfg >> 16) >> (0 << 2)) & 0xf)) - 1;
 	dcscb_allcpus_mask[1] = (1 << (((cfg >> 16) >> (1 << 2)) & 0xf)) - 1;
-	dcscb_usage_count_init();
 
 	ret = mcpm_platform_register(&dcscb_power_ops);
 	if (!ret)

index b0d3c2e876..d4bbbfb5fe 100644
@@ -61,25 +61,7 @@ static void __iomem *ns_sram_base_addr;
 	: "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", \
 	  "r9", "r10", "lr", "memory")
 
-/*
- * We can't use regular spinlocks. In the switcher case, it is possible
- * for an outbound CPU to call power_down() after its inbound counterpart
- * is already live using the same logical CPU number which trips lockdep
- * debugging.
- */
-static arch_spinlock_t exynos_mcpm_lock = __ARCH_SPIN_LOCK_UNLOCKED;
-static int
-cpu_use_count[EXYNOS5420_CPUS_PER_CLUSTER][EXYNOS5420_NR_CLUSTERS];
-
-#define exynos_cluster_usecnt(cluster) \
-	(cpu_use_count[0][cluster] +   \
-	 cpu_use_count[1][cluster] +   \
-	 cpu_use_count[2][cluster] +   \
-	 cpu_use_count[3][cluster])
-
-#define exynos_cluster_unused(cluster) !exynos_cluster_usecnt(cluster)
-
-static int exynos_power_up(unsigned int cpu, unsigned int cluster)
+static int exynos_cpu_powerup(unsigned int cpu, unsigned int cluster)
 {
 	unsigned int cpunr = cpu + (cluster * EXYNOS5420_CPUS_PER_CLUSTER);
 

@@ -88,127 +70,65 @@ static int exynos_power_up(unsigned int cpu, unsigned int cluster)
 		cluster >= EXYNOS5420_NR_CLUSTERS)
 		return -EINVAL;
 
-	/*
-	 * Since this is called with IRQs enabled, and no arch_spin_lock_irq
-	 * variant exists, we need to disable IRQs manually here.
-	 */
-	local_irq_disable();
-	arch_spin_lock(&exynos_mcpm_lock);
-
-	cpu_use_count[cpu][cluster]++;
-	if (cpu_use_count[cpu][cluster] == 1) {
-		bool was_cluster_down =
-			(exynos_cluster_usecnt(cluster) == 1);
-
-		/*
-		 * Turn on the cluster (L2/COMMON) and then power on the
-		 * cores.
-		 */
-		if (was_cluster_down)
-			exynos_cluster_power_up(cluster);
-
-		exynos_cpu_power_up(cpunr);
-	} else if (cpu_use_count[cpu][cluster] != 2) {
-		/*
-		 * The only possible values are:
-		 * 0 = CPU down
-		 * 1 = CPU (still) up
-		 * 2 = CPU requested to be up before it had a chance
-		 *     to actually make itself down.
-		 * Any other value is a bug.
-		 */
-		BUG();
-	}
+	exynos_cpu_power_up(cpunr);
+	return 0;
+}
 
-	arch_spin_unlock(&exynos_mcpm_lock);
-	local_irq_enable();
+static int exynos_cluster_powerup(unsigned int cluster)
+{
+	pr_debug("%s: cluster %u\n", __func__, cluster);
+	if (cluster >= EXYNOS5420_NR_CLUSTERS)
+		return -EINVAL;
 
+	exynos_cluster_power_up(cluster);
 	return 0;
 }
 
-/*
- * NOTE: 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.
- */
-static void exynos_power_down(void)
+static void exynos_cpu_powerdown_prepare(unsigned int cpu, unsigned int cluster)
 {
-	unsigned int mpidr, cpu, cluster;
-	bool last_man = false, skip_wfi = false;
-	unsigned int cpunr;
-
-	mpidr = read_cpuid_mpidr();
-	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
-	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
-	cpunr =  cpu + (cluster * EXYNOS5420_CPUS_PER_CLUSTER);
+	unsigned int cpunr = cpu + (cluster * EXYNOS5420_CPUS_PER_CLUSTER);
 
 	pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
 	BUG_ON(cpu >= EXYNOS5420_CPUS_PER_CLUSTER ||
 			cluster >= EXYNOS5420_NR_CLUSTERS);
+	exynos_cpu_power_down(cpunr);
+}
 
-	__mcpm_cpu_going_down(cpu, cluster);
-
-	arch_spin_lock(&exynos_mcpm_lock);
-	BUG_ON(__mcpm_cluster_state(cluster) != CLUSTER_UP);
-	cpu_use_count[cpu][cluster]--;
-	if (cpu_use_count[cpu][cluster] == 0) {
-		exynos_cpu_power_down(cpunr);
-
-		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.
-		 * Even if we do not want to shut this CPU down,
-		 * the caller expects a certain state as if the WFI
-		 * was aborted.  So let's continue with cache cleaning.
-		 */
-		skip_wfi = true;
-	} else {
-		BUG();
-	}
-
-	if (last_man && __mcpm_outbound_enter_critical(cpu, cluster)) {
-		arch_spin_unlock(&exynos_mcpm_lock);
-
-		if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A15) {
-			/*
-			 * On the Cortex-A15 we need to disable
-			 * L2 prefetching before flushing the cache.
-			 */
-			asm volatile(
-			"mcr	p15, 1, %0, c15, c0, 3\n\t"
-			"isb\n\t"
-			"dsb"
-			: : "r" (0x400));
-		}
+static void exynos_cluster_powerdown_prepare(unsigned int cluster)
+{
+	pr_debug("%s: cluster %u\n", __func__, cluster);
+	BUG_ON(cluster >= EXYNOS5420_NR_CLUSTERS);
+	exynos_cluster_power_down(cluster);
+}
 
-		/* Flush all cache levels for this cluster. */
-		exynos_v7_exit_coherency_flush(all);
+static void exynos_cpu_cache_disable(void)
+{
+	/* Disable and flush the local CPU cache. */
+	exynos_v7_exit_coherency_flush(louis);
+}
 
+static void exynos_cluster_cache_disable(void)
+{
+	if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A15) {
 		/*
-		 * Disable cluster-level coherency by masking
-		 * incoming snoops and DVM messages:
+		 * On the Cortex-A15 we need to disable
+		 * L2 prefetching before flushing the cache.
 		 */
-		cci_disable_port_by_cpu(mpidr);
-
-		__mcpm_outbound_leave_critical(cluster, CLUSTER_DOWN);
-	} else {
-		arch_spin_unlock(&exynos_mcpm_lock);
-
-		/* Disable and flush the local CPU cache. */
-		exynos_v7_exit_coherency_flush(louis);
+		asm volatile(
+		"mcr	p15, 1, %0, c15, c0, 3\n\t"
+		"isb\n\t"
+		"dsb"
+		: : "r" (0x400));
 	}
 
-	__mcpm_cpu_down(cpu, cluster);
-
-	/* Now we are prepared for power-down, do it: */
-	if (!skip_wfi)
-		wfi();
+	/* Flush all cache levels for this cluster. */
+	exynos_v7_exit_coherency_flush(all);
 
-	/* Not dead at this point?  Let our caller cope. */
+	/*
+	 * Disable cluster-level coherency by masking
+	 * incoming snoops and DVM messages:
+	 */
+	cci_disable_port_by_cpu(read_cpuid_mpidr());
 }
 
 static int exynos_wait_for_powerdown(unsigned int cpu, unsigned int cluster)

@@ -222,10 +142,8 @@ static int exynos_wait_for_powerdown(unsigned int cpu, unsigned int cluster)
 
 	/* Wait for the core state to be OFF */
 	while (tries--) {
-		if (ACCESS_ONCE(cpu_use_count[cpu][cluster]) == 0) {
-			if ((exynos_cpu_power_state(cpunr) == 0))
-				return 0; /* success: the CPU is halted */
-		}
+		if ((exynos_cpu_power_state(cpunr) == 0))
+			return 0; /* success: the CPU is halted */
 
 		/* Otherwise, wait and retry: */
 		msleep(1);

@@ -234,63 +152,16 @@ 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,
+	.cpu_powerup		= exynos_cpu_powerup,
+	.cluster_powerup	= exynos_cluster_powerup,
+	.cpu_powerdown_prepare	= exynos_cpu_powerdown_prepare,
+	.cluster_powerdown_prepare = exynos_cluster_powerdown_prepare,
+	.cpu_cache_disable	= exynos_cpu_cache_disable,
+	.cluster_cache_disable	= exynos_cluster_cache_disable,
 	.wait_for_powerdown	= exynos_wait_for_powerdown,
-	.suspend		= exynos_suspend,
-	.powered_up		= exynos_powered_up,
 };
 
-static void __init exynos_mcpm_usage_count_init(void)
-{
-	unsigned int mpidr, cpu, cluster;
-
-	mpidr = read_cpuid_mpidr();
-	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
-	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
-
-	pr_debug("%s: cpu %u cluster %u\n", __func__, cpu, cluster);
-	BUG_ON(cpu >= EXYNOS5420_CPUS_PER_CLUSTER  ||
-			cluster >= EXYNOS5420_NR_CLUSTERS);
-
-	cpu_use_count[cpu][cluster] = 1;
-}
-
 /*
  * Enable cluster-level coherency, in preparation for turning on the MMU.
  */

@@ -302,19 +173,6 @@ 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" },

@@ -370,13 +228,11 @@ static int __init exynos_mcpm_init(void)
 	 */
 	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 */
+		ret = mcpm_loopback(exynos_cluster_cache_disable); /* turn on the CCI */
 	if (ret) {
 		iounmap(ns_sram_base_addr);
 		return ret;

index d4bbbfb5fe..9bdf54795f 100644
@@ -152,6 +152,12 @@ static int exynos_wait_for_powerdown(unsigned int cpu, unsigned int cluster)
 	return -ETIMEDOUT; /* timeout */
 }
 
+static void exynos_cpu_is_up(unsigned int cpu, unsigned int cluster)
+{
+	/* especially when resuming: make sure power control is set */
+	exynos_cpu_powerup(cpu, cluster);
+}
+
 static const struct mcpm_platform_ops exynos_power_ops = {
 	.cpu_powerup		= exynos_cpu_powerup,
 	.cluster_powerup	= exynos_cluster_powerup,

@@ -160,6 +166,7 @@ static const struct mcpm_platform_ops exynos_power_ops = {
 	.cpu_cache_disable	= exynos_cpu_cache_disable,
 	.cluster_cache_disable	= exynos_cluster_cache_disable,
 	.wait_for_powerdown	= exynos_wait_for_powerdown,
+	.cpu_is_up		= exynos_cpu_is_up,
 };
 
 /*

312 lines not on this page · raw message

index 280f3f14f7..880cbfa9c3 100644
@@ -6,6 +6,8 @@
  * under the terms and conditions of the GNU General Public License,
  * version 2, as published by the Free Software Foundation.
  */
+#include <linux/init.h>
+#include <linux/smp.h>
 #include <linux/delay.h>
 #include <linux/io.h>
 #include <linux/memblock.h>

@@ -13,7 +15,9 @@
 
 #include <asm/cputype.h>
 #include <asm/cp15.h>
-#include <asm/mcpm.h>
+#include <asm/cacheflush.h>
+#include <asm/smp.h>
+#include <asm/smp_plat.h>
 
 #include "core.h"
 

@@ -94,11 +98,16 @@ static void hip04_set_snoop_filter(unsigned int cluster, unsigned int on)
 	} while (data != readl_relaxed(fabric + FAB_SF_MODE));
 }
 
-static int hip04_mcpm_power_up(unsigned int cpu, unsigned int cluster)
+static int hip04_boot_secondary(unsigned int l_cpu, struct task_struct *idle)
 {
+	unsigned int mpidr, cpu, cluster;
 	unsigned long data;
 	void __iomem *sys_dreq, *sys_status;
 
+	mpidr = cpu_logical_map(l_cpu);
+	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
+
 	if (!sysctrl)
 		return -ENODEV;
 	if (cluster >= HIP04_MAX_CLUSTERS || cpu >= HIP04_MAX_CPUS_PER_CLUSTER)

@@ -118,6 +127,7 @@ static int hip04_mcpm_power_up(unsigned int cpu, unsigned int cluster)
 			cpu_relax();
 			data = readl_relaxed(sys_status);
 		} while (data & CLUSTER_DEBUG_RESET_STATUS);
+		hip04_set_snoop_filter(cluster, 1);
 	}
 
 	data = CORE_RESET_BIT(cpu) | NEON_RESET_BIT(cpu) | \

@@ -126,11 +136,15 @@ static int hip04_mcpm_power_up(unsigned int cpu, unsigned int cluster)
 	do {
 		cpu_relax();
 	} while (data == readl_relaxed(sys_status));
+
 	/*
 	 * We may fail to power up core again without this delay.
 	 * It's not mentioned in document. It's found by test.
 	 */
 	udelay(20);
+
+	arch_send_wakeup_ipi_mask(cpumask_of(l_cpu));
+
 out:
 	hip04_cpu_table[cluster][cpu]++;
 	spin_unlock_irq(&boot_lock);

@@ -138,31 +152,29 @@ out:
 	return 0;
 }
 
-static void hip04_mcpm_power_down(void)
+static void hip04_cpu_die(unsigned int l_cpu)
 {
 	unsigned int mpidr, cpu, cluster;
-	bool skip_wfi = false, last_man = false;
+	bool last_man;
 
-	mpidr = read_cpuid_mpidr();
+	mpidr = cpu_logical_map(l_cpu);
 	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
 	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
 
-	__mcpm_cpu_going_down(cpu, cluster);
-
 	spin_lock(&boot_lock);
-	BUG_ON(__mcpm_cluster_state(cluster) != CLUSTER_UP);
 	hip04_cpu_table[cluster][cpu]--;
 	if (hip04_cpu_table[cluster][cpu] == 1) {
 		/* A power_up request went ahead of us. */
-		skip_wfi = true;
+		spin_unlock(&boot_lock);
+		return;
 	} else if (hip04_cpu_table[cluster][cpu] > 1) {
 		pr_err("Cluster %d CPU%d boots multiple times\n", cluster, cpu);
 		BUG();
 	}
 
 	last_man = hip04_cluster_is_down(cluster);
-	if (last_man && __mcpm_outbound_enter_critical(cpu, cluster)) {
-		spin_unlock(&boot_lock);
+	spin_unlock(&boot_lock);
+	if (last_man) {
 		/* Since it's Cortex A15, disable L2 prefetching. */
 		asm volatile(
 		"mcr	p15, 1, %0, c15, c0, 3 \n\t"

@@ -170,34 +182,30 @@ static void hip04_mcpm_power_down(void)
 		"dsb	"
 		: : "r" (0x400) );
 		v7_exit_coherency_flush(all);
-		hip04_set_snoop_filter(cluster, 0);
-		__mcpm_outbound_leave_critical(cluster, CLUSTER_DOWN);
 	} else {
-		spin_unlock(&boot_lock);
 		v7_exit_coherency_flush(louis);
 	}
 
-	__mcpm_cpu_down(cpu, cluster);
-
-	if (!skip_wfi)
+	for (;;)
 		wfi();
 }
 
-static int hip04_mcpm_wait_for_powerdown(unsigned int cpu, unsigned int cluster)
+static int hip04_cpu_kill(unsigned int l_cpu)
 {
+	unsigned int mpidr, cpu, cluster;
 	unsigned int data, tries, count;
-	int ret = -ETIMEDOUT;
 
+	mpidr = cpu_logical_map(l_cpu);
+	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
+	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
 	BUG_ON(cluster >= HIP04_MAX_CLUSTERS ||
 	       cpu >= HIP04_MAX_CPUS_PER_CLUSTER);
 
 	count = TIMEOUT_MSEC / POLL_MSEC;
 	spin_lock_irq(&boot_lock);
 	for (tries = 0; tries < count; tries++) {
-		if (hip04_cpu_table[cluster][cpu]) {
-			ret = -EBUSY;
+		if (hip04_cpu_table[cluster][cpu])
 			goto err;
-		}
 		cpu_relax();
 		data = readl_relaxed(sysctrl + SC_CPU_RESET_STATUS(cluster));
 		if (data & CORE_WFI_STATUS(cpu))

@@ -220,64 +228,19 @@ static int hip04_mcpm_wait_for_powerdown(unsigned int cpu, unsigned int cluster)
 	}
 	if (tries >= count)
 		goto err;
+	if (hip04_cluster_is_down(cluster))
+		hip04_set_snoop_filter(cluster, 0);
 	spin_unlock_irq(&boot_lock);
-	return 0;
+	return 1;
 err:
 	spin_unlock_irq(&boot_lock);
-	return ret;
-}
-
-static void hip04_mcpm_powered_up(void)
-{
-	unsigned int mpidr, cpu, cluster;
-
-	mpidr = read_cpuid_mpidr();
-	cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0);
-	cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1);
-
-	spin_lock(&boot_lock);
-	if (!hip04_cpu_table[cluster][cpu])
-		hip04_cpu_table[cluster][cpu] = 1;
-	spin_unlock(&boot_lock);
-}
-
-static void __naked hip04_mcpm_power_up_setup(unsigned int affinity_level)
-{
-	asm volatile ("			\n"
-"	cmp	r0, #0			\n"
-"	bxeq	lr			\n"
-	/* calculate fabric phys address */
-"	adr	r2, 2f			\n"
-"	ldmia	r2, {r1, r3}		\n"
-"	sub	r0, r2, r1		\n"
-"	ldr	r2, [r0, r3]		\n"
-	/* get cluster id from MPIDR */
-"	mrc	p15, 0, r0, c0, c0, 5	\n"
-"	ubfx	r1, r0, #8, #8		\n"
-	/* 1 << cluster id */
-"	mov	r0, #1			\n"
-"	mov	r3, r0, lsl r1		\n"
-"	ldr	r0, [r2, #"__stringify(FAB_SF_MODE)"]	\n"
-"	tst	r0, r3			\n"
-"	bxne	lr			\n"
-"	orr	r1, r0, r3		\n"
-"	str	r1, [r2, #"__stringify(FAB_SF_MODE)"]	\n"
-"1:	ldr	r0, [r2, #"__stringify(FAB_SF_MODE)"]	\n"
-"	tst	r0, r3			\n"
-"	beq	1b			\n"
-"	bx	lr			\n"
-
-"	.align	2			\n"
-"2:	.word	.			\n"
-"	.word	fabric_phys_addr	\n"
-	);
+	return 0;
 }
 
-static const struct mcpm_platform_ops hip04_mcpm_ops = {
-	.power_up		= hip04_mcpm_power_up,
-	.power_down		= hip04_mcpm_power_down,
-	.wait_for_powerdown	= hip04_mcpm_wait_for_powerdown,
-	.powered_up		= hip04_mcpm_powered_up,
+static struct smp_operations __initdata hip04_smp_ops = {
+	.smp_boot_secondary	= hip04_boot_secondary,
+	.cpu_die		= hip04_cpu_die,
+	.cpu_kill		= hip04_cpu_kill,
 };
 
 static bool __init hip04_cpu_table_init(void)

@@ -298,7 +261,7 @@ static bool __init hip04_cpu_table_init(void)
 	return true;
 }
 
-static int __init hip04_mcpm_init(void)
+static int __init hip04_smp_init(void)
 {
 	struct device_node *np, *np_sctl, *np_fab;
 	struct resource fab_res;

@@ -353,10 +316,6 @@ static int __init hip04_mcpm_init(void)
 		ret = -EINVAL;
 		goto err_table;
 	}
-	ret = mcpm_platform_register(&hip04_mcpm_ops);
-	if (ret) {
-		goto err_table;
-	}
 
 	/*
 	 * Fill the instruction address that is used after secondary core

@@ -364,13 +323,11 @@ static int __init hip04_mcpm_init(void)
 	 */
 	writel_relaxed(hip04_boot_method[0], relocation);
 	writel_relaxed(0xa5a5a5a5, relocation + 4);	/* magic number */
-	writel_relaxed(virt_to_phys(mcpm_entry_point), relocation + 8);
+	writel_relaxed(virt_to_phys(secondary_startup), relocation + 8);
 	writel_relaxed(0, relocation + 12);
 	iounmap(relocation);
 
-	mcpm_sync_init(hip04_mcpm_power_up_setup);
-	mcpm_smp_set_ops();
-	pr_info("HiP04 MCPM initialized\n");
+	smp_set_ops(&hip04_smp_ops);
 	return ret;
 err_table:
 	iounmap(fabric);

@@ -383,4 +340,4 @@ err_reloc:
 err:
 	return ret;
 }
-early_initcall(hip04_mcpm_init);
+early_initcall(hip04_smp_init);