/* * OMAP4 CPU idle Routines * * Copyright (C) 2011 Texas Instruments, Inc. * Santosh Shilimkar * Rajendra Nayak * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #include #include #include #include #include #include #include "common.h" #include "pm.h" #include "prm.h" #ifdef CONFIG_CPU_IDLE /* Machine specific information to be recorded in the C-state driver_data */ struct omap4_idle_statedata { u32 cpu_state; u32 mpu_logic_state; u32 mpu_state; u8 valid; }; static struct cpuidle_params cpuidle_params_table[] = { /* C1 - CPU0 ON + CPU1 ON + MPU ON */ {.exit_latency = 2 + 2 , .target_residency = 5, .valid = 1}, /* C2- CPU0 OFF + CPU1 OFF + MPU CSWR */ {.exit_latency = 328 + 440 , .target_residency = 960, .valid = 1}, /* C3 - CPU0 OFF + CPU1 OFF + MPU OSWR */ {.exit_latency = 460 + 518 , .target_residency = 1100, .valid = 1}, }; #define OMAP4_NUM_STATES ARRAY_SIZE(cpuidle_params_table) struct omap4_idle_statedata omap4_idle_data[OMAP4_NUM_STATES]; static struct powerdomain *mpu_pd, *cpu0_pd, *cpu1_pd; /** * omap4_enter_idle - Programs OMAP4 to enter the specified state * @dev: cpuidle device * @drv: cpuidle driver * @index: the index of state to be entered * * Called from the CPUidle framework to program the device to the * specified low power state selected by the governor. * Returns the amount of time spent in the low power state. */ static int omap4_enter_idle(struct cpuidle_device *dev, struct cpuidle_driver *drv, int index) { struct omap4_idle_statedata *cx = cpuidle_get_statedata(&dev->states_usage[index]); struct timespec ts_preidle, ts_postidle, ts_idle; u32 cpu1_state; int idle_time; int new_state_idx; int cpu_id = smp_processor_id(); /* Used to keep track of the total time in idle */ getnstimeofday(&ts_preidle); local_irq_disable(); local_fiq_disable(); /* * CPU0 has to stay ON (i.e in C1) until CPU1 is OFF state. * This is necessary to honour hardware recommondation * of triggeing all the possible low power modes once CPU1 is * out of coherency and in OFF mode. * Update dev->last_state so that governor stats reflects right * data. */ cpu1_state = pwrdm_read_pwrst(cpu1_pd); if (cpu1_state != PWRDM_POWER_OFF) { new_state_idx = drv->safe_state_index; cx = cpuidle_get_statedata(&dev->states_usage[new_state_idx]); } if (index > 0) clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &cpu_id); /* * Call idle CPU PM enter notifier chain so that * VFP and per CPU interrupt context is saved. */ if (cx->cpu_state == PWRDM_POWER_OFF) cpu_pm_enter(); pwrdm_set_logic_retst(mpu_pd, cx->mpu_logic_state); omap_set_pwrdm_state(mpu_pd, cx->mpu_state); /* * Call idle CPU cluster PM enter notifier chain * to save GIC and wakeupgen context. */ if ((cx->mpu_state == PWRDM_POWER_RET) && (cx->mpu_logic_state == PWRDM_POWER_OFF)) cpu_cluster_pm_enter(); omap4_enter_lowpower(dev->cpu, cx->cpu_state); /* * Call idle CPU PM exit notifier chain to restore * VFP and per CPU IRQ context. Only CPU0 state is * considered since CPU1 is managed by CPU hotplug. */ if (pwrdm_read_prev_pwrst(cpu0_pd) == PWRDM_POWER_OFF) cpu_pm_exit(); /* * Call idle CPU cluster PM exit notifier chain * to restore GIC and wakeupgen context. */ if (omap4_mpuss_read_prev_context_state()) cpu_cluster_pm_exit(); if (index > 0) clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &cpu_id); getnstimeofday(&ts_postidle); ts_idle = timespec_sub(ts_postidle, ts_preidle); local_irq_enable(); local_fiq_enable(); idle_time = ts_idle.tv_nsec / NSEC_PER_USEC + ts_idle.tv_sec * \ USEC_PER_SEC; /* Update cpuidle counters */ dev->last_residency = idle_time; return index; } DEFINE_PER_CPU(struct cpuidle_device, omap4_idle_dev); struct cpuidle_driver omap4_idle_driver = { .name = "omap4_idle", .owner = THIS_MODULE, }; static inline void _fill_cstate(struct cpuidle_driver *drv, int idx, const char *descr) { struct cpuidle_state *state = &drv->states[idx]; state->exit_latency = cpuidle_params_table[idx].exit_latency; state->target_residency = cpuidle_params_table[idx].target_residency; state->flags = CPUIDLE_FLAG_TIME_VALID; state->enter = omap4_enter_idle; sprintf(state->name, "C%d", idx + 1); strncpy(state->desc, descr, CPUIDLE_DESC_LEN); } static inline struct omap4_idle_statedata *_fill_cstate_usage( struct cpuidle_device *dev, int idx) { struct omap4_idle_statedata *cx = &omap4_idle_data[idx]; struct cpuidle_state_usage *state_usage = &dev->states_usage[idx]; cx->valid = cpuidle_params_table[idx].valid; cpuidle_set_statedata(state_usage, cx); return cx; } /** * omap4_idle_init - Init routine for OMAP4 idle * * Registers the OMAP4 specific cpuidle driver to the cpuidle * framework with the valid set of states. */ int __init omap4_idle_init(void) { struct omap4_idle_statedata *cx; struct cpuidle_device *dev; struct cpuidle_driver *drv = &omap4_idle_driver; unsigned int cpu_id = 0; mpu_pd = pwrdm_lookup("mpu_pwrdm"); cpu0_pd = pwrdm_lookup("cpu0_pwrdm"); cpu1_pd = pwrdm_lookup("cpu1_pwrdm"); if ((!mpu_pd) || (!cpu0_pd) || (!cpu1_pd)) return -ENODEV; drv->safe_state_index = -1; dev = &per_cpu(omap4_idle_dev, cpu_id); dev->cpu = cpu_id; /* C1 - CPU0 ON + CPU1 ON + MPU ON */ _fill_cstate(drv, 0, "MPUSS ON"); drv->safe_state_index = 0; cx = _fill_cstate_usage(dev, 0); cx->valid = 1; /* C1 is always valid */ cx->cpu_state = PWRDM_POWER_ON; cx->mpu_state = PWRDM_POWER_ON; cx->mpu_logic_state = PWRDM_POWER_RET; /* C2 - CPU0 OFF + CPU1 OFF + MPU CSWR */ _fill_cstate(drv, 1, "MPUSS CSWR"); cx = _fill_cstate_usage(dev, 1); cx->cpu_state = PWRDM_POWER_OFF; cx->mpu_state = PWRDM_POWER_RET; cx->mpu_logic_state = PWRDM_POWER_RET; /* C3 - CPU0 OFF + CPU1 OFF + MPU OSWR */ _fill_cstate(drv, 2, "MPUSS OSWR"); cx = _fill_cstate_usage(dev, 2); cx->cpu_state = PWRDM_POWER_OFF; cx->mpu_state = PWRDM_POWER_RET; cx->mpu_logic_state = PWRDM_POWER_OFF; drv->state_count = OMAP4_NUM_STATES; cpuidle_register_driver(&omap4_idle_driver); dev->state_count = OMAP4_NUM_STATES; if (cpuidle_register_device(dev)) { pr_err("%s: CPUidle register device failed\n", __func__); return -EIO; } return 0; } #else int __init omap4_idle_init(void) { return 0; } #endif /* CONFIG_CPU_IDLE */