diff options
Diffstat (limited to 'drivers/cpuidle')
| -rw-r--r-- | drivers/cpuidle/Kconfig | 5 | ||||
| -rw-r--r-- | drivers/cpuidle/Kconfig.mips | 17 | ||||
| -rw-r--r-- | drivers/cpuidle/Makefile | 4 | ||||
| -rw-r--r-- | drivers/cpuidle/cpuidle-armada-370-xp.c | 4 | ||||
| -rw-r--r-- | drivers/cpuidle/cpuidle-cps.c | 186 | ||||
| -rw-r--r-- | drivers/cpuidle/cpuidle-powernv.c | 8 | ||||
| -rw-r--r-- | drivers/cpuidle/driver.c | 7 |
7 files changed, 222 insertions, 9 deletions
diff --git a/drivers/cpuidle/Kconfig b/drivers/cpuidle/Kconfig index f04e25f6c98..1b96fb91d32 100644 --- a/drivers/cpuidle/Kconfig +++ b/drivers/cpuidle/Kconfig @@ -35,6 +35,11 @@ depends on ARM source "drivers/cpuidle/Kconfig.arm" endmenu +menu "MIPS CPU Idle Drivers" +depends on MIPS +source "drivers/cpuidle/Kconfig.mips" +endmenu + menu "POWERPC CPU Idle Drivers" depends on PPC source "drivers/cpuidle/Kconfig.powerpc" diff --git a/drivers/cpuidle/Kconfig.mips b/drivers/cpuidle/Kconfig.mips new file mode 100644 index 00000000000..0e70ee28a5c --- /dev/null +++ b/drivers/cpuidle/Kconfig.mips @@ -0,0 +1,17 @@ +# +# MIPS CPU Idle Drivers +# +config MIPS_CPS_CPUIDLE + bool "CPU Idle driver for MIPS CPS platforms" + depends on CPU_IDLE + depends on SYS_SUPPORTS_MIPS_CPS + select ARCH_NEEDS_CPU_IDLE_COUPLED if MIPS_MT + select GENERIC_CLOCKEVENTS_BROADCAST if SMP + select MIPS_CPS_PM + default y + help + Select this option to enable processor idle state management + through cpuidle for systems built around the MIPS Coherent + Processing System (CPS) architecture. In order to make use of + the deepest idle states you will need to ensure that you are + also using the CONFIG_MIPS_CPS SMP implementation. diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile index 9b5b2b560d7..d8bb1ff7256 100644 --- a/drivers/cpuidle/Makefile +++ b/drivers/cpuidle/Makefile @@ -18,6 +18,10 @@ obj-$(CONFIG_ARM_AT91_CPUIDLE) += cpuidle-at91.o obj-$(CONFIG_ARM_EXYNOS_CPUIDLE) += cpuidle-exynos.o ############################################################################### +# MIPS drivers +obj-$(CONFIG_MIPS_CPS_CPUIDLE) += cpuidle-cps.o + +############################################################################### # POWERPC drivers obj-$(CONFIG_PSERIES_CPUIDLE) += cpuidle-pseries.o obj-$(CONFIG_POWERNV_CPUIDLE) += cpuidle-powernv.o diff --git a/drivers/cpuidle/cpuidle-armada-370-xp.c b/drivers/cpuidle/cpuidle-armada-370-xp.c index 28587d0f394..a5fba0287bf 100644 --- a/drivers/cpuidle/cpuidle-armada-370-xp.c +++ b/drivers/cpuidle/cpuidle-armada-370-xp.c @@ -55,7 +55,7 @@ static struct cpuidle_driver armada_370_xp_idle_driver = { .power_usage = 50, .target_residency = 100, .flags = CPUIDLE_FLAG_TIME_VALID, - .name = "MV CPU IDLE", + .name = "Idle", .desc = "CPU power down", }, .states[2] = { @@ -65,7 +65,7 @@ static struct cpuidle_driver armada_370_xp_idle_driver = { .target_residency = 1000, .flags = CPUIDLE_FLAG_TIME_VALID | ARMADA_370_XP_FLAG_DEEP_IDLE, - .name = "MV CPU DEEP IDLE", + .name = "Deep idle", .desc = "CPU and L2 Fabric power down", }, .state_count = ARMADA_370_XP_MAX_STATES, diff --git a/drivers/cpuidle/cpuidle-cps.c b/drivers/cpuidle/cpuidle-cps.c new file mode 100644 index 00000000000..fc7b62720de --- /dev/null +++ b/drivers/cpuidle/cpuidle-cps.c @@ -0,0 +1,186 @@ +/* + * Copyright (C) 2014 Imagination Technologies + * Author: Paul Burton <paul.burton@imgtec.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + */ + +#include <linux/cpu_pm.h> +#include <linux/cpuidle.h> +#include <linux/init.h> + +#include <asm/idle.h> +#include <asm/pm-cps.h> + +/* Enumeration of the various idle states this driver may enter */ +enum cps_idle_state { + STATE_WAIT = 0, /* MIPS wait instruction, coherent */ + STATE_NC_WAIT, /* MIPS wait instruction, non-coherent */ + STATE_CLOCK_GATED, /* Core clock gated */ + STATE_POWER_GATED, /* Core power gated */ + STATE_COUNT +}; + +static int cps_nc_enter(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) +{ + enum cps_pm_state pm_state; + int err; + + /* + * At least one core must remain powered up & clocked in order for the + * system to have any hope of functioning. + * + * TODO: don't treat core 0 specially, just prevent the final core + * TODO: remap interrupt affinity temporarily + */ + if (!cpu_data[dev->cpu].core && (index > STATE_NC_WAIT)) + index = STATE_NC_WAIT; + + /* Select the appropriate cps_pm_state */ + switch (index) { + case STATE_NC_WAIT: + pm_state = CPS_PM_NC_WAIT; + break; + case STATE_CLOCK_GATED: + pm_state = CPS_PM_CLOCK_GATED; + break; + case STATE_POWER_GATED: + pm_state = CPS_PM_POWER_GATED; + break; + default: + BUG(); + return -EINVAL; + } + + /* Notify listeners the CPU is about to power down */ + if ((pm_state == CPS_PM_POWER_GATED) && cpu_pm_enter()) + return -EINTR; + + /* Enter that state */ + err = cps_pm_enter_state(pm_state); + + /* Notify listeners the CPU is back up */ + if (pm_state == CPS_PM_POWER_GATED) + cpu_pm_exit(); + + return err ?: index; +} + +static struct cpuidle_driver cps_driver = { + .name = "cpc_cpuidle", + .owner = THIS_MODULE, + .states = { + [STATE_WAIT] = MIPS_CPUIDLE_WAIT_STATE, + [STATE_NC_WAIT] = { + .enter = cps_nc_enter, + .exit_latency = 200, + .target_residency = 450, + .flags = CPUIDLE_FLAG_TIME_VALID, + .name = "nc-wait", + .desc = "non-coherent MIPS wait", + }, + [STATE_CLOCK_GATED] = { + .enter = cps_nc_enter, + .exit_latency = 300, + .target_residency = 700, + .flags = CPUIDLE_FLAG_TIME_VALID | + CPUIDLE_FLAG_TIMER_STOP, + .name = "clock-gated", + .desc = "core clock gated", + }, + [STATE_POWER_GATED] = { + .enter = cps_nc_enter, + .exit_latency = 600, + .target_residency = 1000, + .flags = CPUIDLE_FLAG_TIME_VALID | + CPUIDLE_FLAG_TIMER_STOP, + .name = "power-gated", + .desc = "core power gated", + }, + }, + .state_count = STATE_COUNT, + .safe_state_index = 0, +}; + +static void __init cps_cpuidle_unregister(void) +{ + int cpu; + struct cpuidle_device *device; + + for_each_possible_cpu(cpu) { + device = &per_cpu(cpuidle_dev, cpu); + cpuidle_unregister_device(device); + } + + cpuidle_unregister_driver(&cps_driver); +} + +static int __init cps_cpuidle_init(void) +{ + int err, cpu, core, i; + struct cpuidle_device *device; + + /* Detect supported states */ + if (!cps_pm_support_state(CPS_PM_POWER_GATED)) + cps_driver.state_count = STATE_CLOCK_GATED + 1; + if (!cps_pm_support_state(CPS_PM_CLOCK_GATED)) + cps_driver.state_count = STATE_NC_WAIT + 1; + if (!cps_pm_support_state(CPS_PM_NC_WAIT)) + cps_driver.state_count = STATE_WAIT + 1; + + /* Inform the user if some states are unavailable */ + if (cps_driver.state_count < STATE_COUNT) { + pr_info("cpuidle-cps: limited to "); + switch (cps_driver.state_count - 1) { + case STATE_WAIT: + pr_cont("coherent wait\n"); + break; + case STATE_NC_WAIT: + pr_cont("non-coherent wait\n"); + break; + case STATE_CLOCK_GATED: + pr_cont("clock gating\n"); + break; + } + } + + /* + * Set the coupled flag on the appropriate states if this system + * requires it. + */ + if (coupled_coherence) + for (i = STATE_NC_WAIT; i < cps_driver.state_count; i++) + cps_driver.states[i].flags |= CPUIDLE_FLAG_COUPLED; + + err = cpuidle_register_driver(&cps_driver); + if (err) { + pr_err("Failed to register CPS cpuidle driver\n"); + return err; + } + + for_each_possible_cpu(cpu) { + core = cpu_data[cpu].core; + device = &per_cpu(cpuidle_dev, cpu); + device->cpu = cpu; +#ifdef CONFIG_MIPS_MT + cpumask_copy(&device->coupled_cpus, &cpu_sibling_map[cpu]); +#endif + + err = cpuidle_register_device(device); + if (err) { + pr_err("Failed to register CPU%d cpuidle device\n", + cpu); + goto err_out; + } + } + + return 0; +err_out: + cps_cpuidle_unregister(); + return err; +} +device_initcall(cps_cpuidle_init); diff --git a/drivers/cpuidle/cpuidle-powernv.c b/drivers/cpuidle/cpuidle-powernv.c index 719f6fb5b1c..74f5788d50b 100644 --- a/drivers/cpuidle/cpuidle-powernv.c +++ b/drivers/cpuidle/cpuidle-powernv.c @@ -73,12 +73,10 @@ static int fastsleep_loop(struct cpuidle_device *dev, return index; new_lpcr = old_lpcr; - new_lpcr &= ~(LPCR_MER | LPCR_PECE); /* lpcr[mer] must be 0 */ - - /* exit powersave upon external interrupt, but not decrementer - * interrupt. + /* Do not exit powersave upon decrementer as we've setup the timer + * offload. */ - new_lpcr |= LPCR_PECE0; + new_lpcr &= ~LPCR_PECE1; mtspr(SPRN_LPCR, new_lpcr); power7_sleep(); diff --git a/drivers/cpuidle/driver.c b/drivers/cpuidle/driver.c index 136d6a283e0..9634f20e392 100644 --- a/drivers/cpuidle/driver.c +++ b/drivers/cpuidle/driver.c @@ -187,8 +187,11 @@ static int poll_idle(struct cpuidle_device *dev, t1 = ktime_get(); local_irq_enable(); - while (!need_resched()) - cpu_relax(); + if (!current_set_polling_and_test()) { + while (!need_resched()) + cpu_relax(); + } + current_clr_polling(); t2 = ktime_get(); diff = ktime_to_us(ktime_sub(t2, t1)); |