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-rw-r--r--arch/arm/mach-vexpress/tc2_pm.c291
1 files changed, 81 insertions, 210 deletions
diff --git a/arch/arm/mach-vexpress/tc2_pm.c b/arch/arm/mach-vexpress/tc2_pm.c
index 2fb78b4648cb..b3328cd46c33 100644
--- a/arch/arm/mach-vexpress/tc2_pm.c
+++ b/arch/arm/mach-vexpress/tc2_pm.c
@@ -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 at 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;
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-29 19:45:40 +0100