2 * OMAP4+ CPU idle Routines
4 * Copyright (C) 2011-2013 Texas Instruments, Inc.
5 * Santosh Shilimkar <santosh.shilimkar@ti.com>
6 * Rajendra Nayak <rnayak@ti.com>
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
13 #include <linux/sched.h>
14 #include <linux/cpuidle.h>
15 #include <linux/cpu_pm.h>
16 #include <linux/export.h>
18 #include <asm/proc-fns.h>
23 #include "clockdomain.h"
25 /* Machine specific information */
26 struct idle_statedata {
32 static struct idle_statedata omap4_idle_data[] = {
34 .cpu_state = PWRDM_POWER_ON,
35 .mpu_state = PWRDM_POWER_ON,
36 .mpu_logic_state = PWRDM_POWER_RET,
39 .cpu_state = PWRDM_POWER_OFF,
40 .mpu_state = PWRDM_POWER_RET,
41 .mpu_logic_state = PWRDM_POWER_RET,
44 .cpu_state = PWRDM_POWER_OFF,
45 .mpu_state = PWRDM_POWER_RET,
46 .mpu_logic_state = PWRDM_POWER_OFF,
50 static struct powerdomain *mpu_pd, *cpu_pd[NR_CPUS];
51 static struct clockdomain *cpu_clkdm[NR_CPUS];
53 static atomic_t abort_barrier;
54 static bool cpu_done[NR_CPUS];
55 static struct idle_statedata *state_ptr = &omap4_idle_data[0];
57 /* Private functions */
60 * omap_enter_idle_[simple/coupled] - OMAP4PLUS cpuidle entry functions
61 * @dev: cpuidle device
62 * @drv: cpuidle driver
63 * @index: the index of state to be entered
65 * Called from the CPUidle framework to program the device to the
66 * specified low power state selected by the governor.
67 * Returns the amount of time spent in the low power state.
69 static int omap_enter_idle_simple(struct cpuidle_device *dev,
70 struct cpuidle_driver *drv,
80 static int omap_enter_idle_coupled(struct cpuidle_device *dev,
81 struct cpuidle_driver *drv,
84 struct idle_statedata *cx = state_ptr + index;
89 * CPU0 has to wait and stay ON until CPU1 is OFF state.
90 * This is necessary to honour hardware recommondation
91 * of triggeing all the possible low power modes once CPU1 is
92 * out of coherency and in OFF mode.
94 if (dev->cpu == 0 && cpumask_test_cpu(1, cpu_online_mask)) {
95 while (pwrdm_read_pwrst(cpu_pd[1]) != PWRDM_POWER_OFF) {
99 * CPU1 could have already entered & exited idle
100 * without hitting off because of a wakeup
101 * or a failed attempt to hit off mode. Check for
102 * that here, otherwise we could spin forever
103 * waiting for CPU1 off.
112 * Call idle CPU PM enter notifier chain so that
113 * VFP and per CPU interrupt context is saved.
118 pwrdm_set_logic_retst(mpu_pd, cx->mpu_logic_state);
119 omap_set_pwrdm_state(mpu_pd, cx->mpu_state);
122 * Call idle CPU cluster PM enter notifier chain
123 * to save GIC and wakeupgen context.
125 if ((cx->mpu_state == PWRDM_POWER_RET) &&
126 (cx->mpu_logic_state == PWRDM_POWER_OFF))
127 cpu_cluster_pm_enter();
130 omap4_enter_lowpower(dev->cpu, cx->cpu_state);
131 cpu_done[dev->cpu] = true;
133 /* Wakeup CPU1 only if it is not offlined */
134 if (dev->cpu == 0 && cpumask_test_cpu(1, cpu_online_mask)) {
135 clkdm_wakeup(cpu_clkdm[1]);
136 clkdm_allow_idle(cpu_clkdm[1]);
140 * Call idle CPU PM exit notifier chain to restore
141 * VFP and per CPU IRQ context.
146 * Call idle CPU cluster PM exit notifier chain
147 * to restore GIC and wakeupgen context.
149 if ((cx->mpu_state == PWRDM_POWER_RET) &&
150 (cx->mpu_logic_state == PWRDM_POWER_OFF))
151 cpu_cluster_pm_exit();
154 cpuidle_coupled_parallel_barrier(dev, &abort_barrier);
155 cpu_done[dev->cpu] = false;
162 static DEFINE_PER_CPU(struct cpuidle_device, omap_idle_dev);
164 static struct cpuidle_driver omap4_idle_driver = {
165 .name = "omap4_idle",
166 .owner = THIS_MODULE,
167 .en_core_tk_irqen = 1,
170 /* C1 - CPU0 ON + CPU1 ON + MPU ON */
171 .exit_latency = 2 + 2,
172 .target_residency = 5,
173 .flags = CPUIDLE_FLAG_TIME_VALID,
174 .enter = omap_enter_idle_simple,
176 .desc = "CPUx ON, MPUSS ON"
179 /* C2 - CPU0 OFF + CPU1 OFF + MPU CSWR */
180 .exit_latency = 328 + 440,
181 .target_residency = 960,
182 .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_COUPLED |
183 CPUIDLE_FLAG_TIMER_STOP,
184 .enter = omap_enter_idle_coupled,
186 .desc = "CPUx OFF, MPUSS CSWR",
189 /* C3 - CPU0 OFF + CPU1 OFF + MPU OSWR */
190 .exit_latency = 460 + 518,
191 .target_residency = 1100,
192 .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_COUPLED |
193 CPUIDLE_FLAG_TIMER_STOP,
194 .enter = omap_enter_idle_coupled,
196 .desc = "CPUx OFF, MPUSS OSWR",
199 .state_count = ARRAY_SIZE(omap4_idle_data),
200 .safe_state_index = 0,
203 /* Public functions */
206 * omap4_idle_init - Init routine for OMAP4+ idle
208 * Registers the OMAP4+ specific cpuidle driver to the cpuidle
209 * framework with the valid set of states.
211 int __init omap4_idle_init(void)
213 struct cpuidle_device *dev;
214 unsigned int cpu_id = 0;
216 mpu_pd = pwrdm_lookup("mpu_pwrdm");
217 cpu_pd[0] = pwrdm_lookup("cpu0_pwrdm");
218 cpu_pd[1] = pwrdm_lookup("cpu1_pwrdm");
219 if ((!mpu_pd) || (!cpu_pd[0]) || (!cpu_pd[1]))
222 cpu_clkdm[0] = clkdm_lookup("mpu0_clkdm");
223 cpu_clkdm[1] = clkdm_lookup("mpu1_clkdm");
224 if (!cpu_clkdm[0] || !cpu_clkdm[1])
227 if (cpuidle_register_driver(&omap4_idle_driver)) {
228 pr_err("%s: CPUidle driver register failed\n", __func__);
232 for_each_cpu(cpu_id, cpu_online_mask) {
233 dev = &per_cpu(omap_idle_dev, cpu_id);
235 #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED
236 dev->coupled_cpus = *cpu_online_mask;
238 if (cpuidle_register_device(dev)) {
239 pr_err("%s: CPUidle register failed\n", __func__);
240 cpuidle_unregister_driver(&omap4_idle_driver);