diff options
Diffstat (limited to 'arch/arm/mach-exynos/mcpm-exynos.c')
| -rw-r--r-- | arch/arm/mach-exynos/mcpm-exynos.c | 247 |
1 files changed, 55 insertions, 192 deletions
diff --git a/arch/arm/mach-exynos/mcpm-exynos.c b/arch/arm/mach-exynos/mcpm-exynos.c index b0d3c2e876fb..9bdf54795f05 100644 --- a/arch/arm/mach-exynos/mcpm-exynos.c +++ b/arch/arm/mach-exynos/mcpm-exynos.c @@ -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 +152,23 @@ 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) +static void exynos_cpu_is_up(unsigned int cpu, unsigned int cluster) { - 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); + /* especially when resuming: make sure power control is set */ + exynos_cpu_powerup(cpu, cluster); } 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, + .cpu_is_up = exynos_cpu_is_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 +180,6 @@ 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 +235,11 @@ 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; |