diff options
Diffstat (limited to 'arch/arm/mach-tegra/cpuidle-tegra20.c')
| -rw-r--r-- | arch/arm/mach-tegra/cpuidle-tegra20.c | 197 |
1 files changed, 193 insertions, 4 deletions
diff --git a/arch/arm/mach-tegra/cpuidle-tegra20.c b/arch/arm/mach-tegra/cpuidle-tegra20.c index d32e8b0dbd4f..825ced4f7a40 100644 --- a/arch/arm/mach-tegra/cpuidle-tegra20.c +++ b/arch/arm/mach-tegra/cpuidle-tegra20.c @@ -22,21 +22,199 @@ #include <linux/kernel.h> #include <linux/module.h> #include <linux/cpuidle.h> +#include <linux/cpu_pm.h> +#include <linux/clockchips.h> +#include <linux/clk/tegra.h> #include <asm/cpuidle.h> +#include <asm/proc-fns.h> +#include <asm/suspend.h> +#include <asm/smp_plat.h> + +#include "pm.h" +#include "sleep.h" +#include "iomap.h" +#include "irq.h" +#include "flowctrl.h" + +#ifdef CONFIG_PM_SLEEP +static bool abort_flag; +static atomic_t abort_barrier; +static int tegra20_idle_lp2_coupled(struct cpuidle_device *dev, + struct cpuidle_driver *drv, + int index); +#endif + +static struct cpuidle_state tegra_idle_states[] = { + [0] = ARM_CPUIDLE_WFI_STATE_PWR(600), +#ifdef CONFIG_PM_SLEEP + [1] = { + .enter = tegra20_idle_lp2_coupled, + .exit_latency = 5000, + .target_residency = 10000, + .power_usage = 0, + .flags = CPUIDLE_FLAG_TIME_VALID | + CPUIDLE_FLAG_COUPLED, + .name = "powered-down", + .desc = "CPU power gated", + }, +#endif +}; static struct cpuidle_driver tegra_idle_driver = { .name = "tegra_idle", .owner = THIS_MODULE, .en_core_tk_irqen = 1, - .state_count = 1, - .states = { - [0] = ARM_CPUIDLE_WFI_STATE_PWR(600), - }, }; static DEFINE_PER_CPU(struct cpuidle_device, tegra_idle_device); +#ifdef CONFIG_PM_SLEEP +#ifdef CONFIG_SMP +static void __iomem *pmc = IO_ADDRESS(TEGRA_PMC_BASE); + +static int tegra20_reset_sleeping_cpu_1(void) +{ + int ret = 0; + + tegra_pen_lock(); + + if (readl(pmc + PMC_SCRATCH41) == CPU_RESETTABLE) + tegra20_cpu_shutdown(1); + else + ret = -EINVAL; + + tegra_pen_unlock(); + + return ret; +} + +static void tegra20_wake_cpu1_from_reset(void) +{ + tegra_pen_lock(); + + tegra20_cpu_clear_resettable(); + + /* enable cpu clock on cpu */ + tegra_enable_cpu_clock(1); + + /* take the CPU out of reset */ + tegra_cpu_out_of_reset(1); + + /* unhalt the cpu */ + flowctrl_write_cpu_halt(1, 0); + + tegra_pen_unlock(); +} + +static int tegra20_reset_cpu_1(void) +{ + if (!cpu_online(1) || !tegra20_reset_sleeping_cpu_1()) + return 0; + + tegra20_wake_cpu1_from_reset(); + return -EBUSY; +} +#else +static inline void tegra20_wake_cpu1_from_reset(void) +{ +} + +static inline int tegra20_reset_cpu_1(void) +{ + return 0; +} +#endif + +static bool tegra20_cpu_cluster_power_down(struct cpuidle_device *dev, + struct cpuidle_driver *drv, + int index) +{ + struct cpuidle_state *state = &drv->states[index]; + u32 cpu_on_time = state->exit_latency; + u32 cpu_off_time = state->target_residency - state->exit_latency; + + while (tegra20_cpu_is_resettable_soon()) + cpu_relax(); + + if (tegra20_reset_cpu_1() || !tegra_cpu_rail_off_ready()) + return false; + + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &dev->cpu); + + tegra_idle_lp2_last(cpu_on_time, cpu_off_time); + + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &dev->cpu); + + if (cpu_online(1)) + tegra20_wake_cpu1_from_reset(); + + return true; +} + +#ifdef CONFIG_SMP +static bool tegra20_idle_enter_lp2_cpu_1(struct cpuidle_device *dev, + struct cpuidle_driver *drv, + int index) +{ + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &dev->cpu); + + cpu_suspend(0, tegra20_sleep_cpu_secondary_finish); + + tegra20_cpu_clear_resettable(); + + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &dev->cpu); + + return true; +} +#else +static inline bool tegra20_idle_enter_lp2_cpu_1(struct cpuidle_device *dev, + struct cpuidle_driver *drv, + int index) +{ + return true; +} +#endif + +static int tegra20_idle_lp2_coupled(struct cpuidle_device *dev, + struct cpuidle_driver *drv, + int index) +{ + u32 cpu = is_smp() ? cpu_logical_map(dev->cpu) : dev->cpu; + bool entered_lp2 = false; + + if (tegra_pending_sgi()) + ACCESS_ONCE(abort_flag) = true; + + cpuidle_coupled_parallel_barrier(dev, &abort_barrier); + + if (abort_flag) { + cpuidle_coupled_parallel_barrier(dev, &abort_barrier); + abort_flag = false; /* clean flag for next coming */ + return -EINTR; + } + + local_fiq_disable(); + + tegra_set_cpu_in_lp2(cpu); + cpu_pm_enter(); + + if (cpu == 0) + entered_lp2 = tegra20_cpu_cluster_power_down(dev, drv, index); + else + entered_lp2 = tegra20_idle_enter_lp2_cpu_1(dev, drv, index); + + cpu_pm_exit(); + tegra_clear_cpu_in_lp2(cpu); + + local_fiq_enable(); + + smp_rmb(); + + return entered_lp2 ? index : 0; +} +#endif + int __init tegra20_cpuidle_init(void) { int ret; @@ -44,6 +222,14 @@ int __init tegra20_cpuidle_init(void) struct cpuidle_device *dev; struct cpuidle_driver *drv = &tegra_idle_driver; +#ifdef CONFIG_PM_SLEEP + tegra_tear_down_cpu = tegra20_tear_down_cpu; +#endif + + drv->state_count = ARRAY_SIZE(tegra_idle_states); + memcpy(drv->states, tegra_idle_states, + drv->state_count * sizeof(drv->states[0])); + ret = cpuidle_register_driver(&tegra_idle_driver); if (ret) { pr_err("CPUidle driver registration failed\n"); @@ -53,6 +239,9 @@ int __init tegra20_cpuidle_init(void) for_each_possible_cpu(cpu) { dev = &per_cpu(tegra_idle_device, cpu); dev->cpu = cpu; +#ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED + dev->coupled_cpus = *cpu_possible_mask; +#endif dev->state_count = drv->state_count; ret = cpuidle_register_device(dev); |