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author | Linus Torvalds <torvalds@linux-foundation.org> | 2012-05-22 18:41:01 +0200 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2012-05-22 18:41:01 +0200 |
commit | cdd3a354a05b0c33fe33ab11a0fb0838396cad19 (patch) | |
tree | ea2c87bbc2dc5865a97e73e201661d69937b45d5 /arch/arm/mach-ux500 | |
parent | Merge tag 'pinctrl' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc (diff) | |
parent | Merge branch 'next/cpuidle' into next/pm (diff) | |
download | linux-cdd3a354a05b0c33fe33ab11a0fb0838396cad19.tar.xz linux-cdd3a354a05b0c33fe33ab11a0fb0838396cad19.zip |
Merge tag 'pm' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull arm-soc power management changes from Olof Johansson:
"Power management changes here are mostly for the omap platform, but
also include cpuidle changes for ux500 and suspend/resume code for
mmp."
* tag 'pm' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (48 commits)
ARM: OMAP2+: WDTIMER integration: fix !PM boot crash, disarm timer after hwmod reset
ARM: OMAP2/3: hwmod data: Add 32k-sync timer data to hwmod database
ARM: OMAP4: hwmod_data: Name the common irq for McBSP ports
ARM: OMAP4: hwmod data: I2C: add flag for context restore
ARM: OMAP3: hwmod_data: Rename the common irq for McBSP ports
ARM: OMAP2xxx: hwmod data: add HDQ/1-wire hwmod
ARM: OMAP3: hwmod data: add HDQ/1-wire hwmod
ARM: OMAP2+: hwmod data: add HDQ/1-wire hwmod shared data
ARM: OMAP2+: HDQ1W: add custom reset function
ARM: OMAP2420: hwmod data: Add MMC hwmod data for 2420
arm: omap3: clockdomain data: Remove superfluous commas from gfx_sgx_3xxx_wkdeps[]
ARM: OMAP2+: powerdomain: Get rid off duplicate pwrdm_clkdm_state_switch() API
ARM: OMAP3: clock data: add clockdomain for HDQ functional clock
ARM: OMAP3+: dpll: Configure autoidle mode only if it's supported
ARM: OMAP2+: dmtimer: cleanup iclk usage
ARM: OMAP4+: Add prm and cm base init function.
ARM: OMAP2/3: Add idle_st bits for ST_32KSYNC timer to prcm-common header
ARM: OMAP3: Fix CM register bit masks
ARM: OMAP: clock: convert AM3517/3505 detection/flags to AM35xx
ARM: OMAP3: clock data: treat all AM35x devices the same
...
Diffstat (limited to 'arch/arm/mach-ux500')
-rw-r--r-- | arch/arm/mach-ux500/Makefile | 1 | ||||
-rw-r--r-- | arch/arm/mach-ux500/cpuidle.c | 171 |
2 files changed, 172 insertions, 0 deletions
diff --git a/arch/arm/mach-ux500/Makefile b/arch/arm/mach-ux500/Makefile index 041c35885981..026086ff9e6c 100644 --- a/arch/arm/mach-ux500/Makefile +++ b/arch/arm/mach-ux500/Makefile @@ -4,6 +4,7 @@ obj-y := clock.o cpu.o devices.o devices-common.o \ id.o usb.o timer.o +obj-$(CONFIG_CPU_IDLE) += cpuidle.o obj-$(CONFIG_CACHE_L2X0) += cache-l2x0.o obj-$(CONFIG_UX500_SOC_DB8500) += cpu-db8500.o devices-db8500.o obj-$(CONFIG_MACH_MOP500) += board-mop500.o board-mop500-sdi.o \ diff --git a/arch/arm/mach-ux500/cpuidle.c b/arch/arm/mach-ux500/cpuidle.c new file mode 100644 index 000000000000..b54884bd2549 --- /dev/null +++ b/arch/arm/mach-ux500/cpuidle.c @@ -0,0 +1,171 @@ +/* + * Copyright (c) 2012 Linaro : Daniel Lezcano <daniel.lezcano@linaro.org> (IBM) + * + * Based on the work of Rickard Andersson <rickard.andersson@stericsson.com> + * and Jonas Aaberg <jonas.aberg@stericsson.com>. + * + * 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 <linux/module.h> +#include <linux/cpuidle.h> +#include <linux/clockchips.h> +#include <linux/spinlock.h> +#include <linux/atomic.h> +#include <linux/smp.h> +#include <linux/mfd/dbx500-prcmu.h> + +#include <asm/cpuidle.h> +#include <asm/proc-fns.h> + +static atomic_t master = ATOMIC_INIT(0); +static DEFINE_SPINLOCK(master_lock); +static DEFINE_PER_CPU(struct cpuidle_device, ux500_cpuidle_device); + +static inline int ux500_enter_idle(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) +{ + int this_cpu = smp_processor_id(); + bool recouple = false; + + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &this_cpu); + + if (atomic_inc_return(&master) == num_online_cpus()) { + + /* With this lock, we prevent the other cpu to exit and enter + * this function again and become the master */ + if (!spin_trylock(&master_lock)) + goto wfi; + + /* decouple the gic from the A9 cores */ + if (prcmu_gic_decouple()) + goto out; + + /* If an error occur, we will have to recouple the gic + * manually */ + recouple = true; + + /* At this state, as the gic is decoupled, if the other + * cpu is in WFI, we have the guarantee it won't be wake + * up, so we can safely go to retention */ + if (!prcmu_is_cpu_in_wfi(this_cpu ? 0 : 1)) + goto out; + + /* The prcmu will be in charge of watching the interrupts + * and wake up the cpus */ + if (prcmu_copy_gic_settings()) + goto out; + + /* Check in the meantime an interrupt did + * not occur on the gic ... */ + if (prcmu_gic_pending_irq()) + goto out; + + /* ... and the prcmu */ + if (prcmu_pending_irq()) + goto out; + + /* Go to the retention state, the prcmu will wait for the + * cpu to go WFI and this is what happens after exiting this + * 'master' critical section */ + if (prcmu_set_power_state(PRCMU_AP_IDLE, true, true)) + goto out; + + /* When we switch to retention, the prcmu is in charge + * of recoupling the gic automatically */ + recouple = false; + + spin_unlock(&master_lock); + } +wfi: + cpu_do_idle(); +out: + atomic_dec(&master); + + if (recouple) { + prcmu_gic_recouple(); + spin_unlock(&master_lock); + } + + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &this_cpu); + + return index; +} + +static struct cpuidle_driver ux500_idle_driver = { + .name = "ux500_idle", + .owner = THIS_MODULE, + .en_core_tk_irqen = 1, + .states = { + ARM_CPUIDLE_WFI_STATE, + { + .enter = ux500_enter_idle, + .exit_latency = 70, + .target_residency = 260, + .flags = CPUIDLE_FLAG_TIME_VALID, + .name = "ApIdle", + .desc = "ARM Retention", + }, + }, + .safe_state_index = 0, + .state_count = 2, +}; + +/* + * For each cpu, setup the broadcast timer because we will + * need to migrate the timers for the states >= ApIdle. + */ +static void ux500_setup_broadcast_timer(void *arg) +{ + int cpu = smp_processor_id(); + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ON, &cpu); +} + +int __init ux500_idle_init(void) +{ + int ret, cpu; + struct cpuidle_device *device; + + /* Configure wake up reasons */ + prcmu_enable_wakeups(PRCMU_WAKEUP(ARM) | PRCMU_WAKEUP(RTC) | + PRCMU_WAKEUP(ABB)); + + /* + * Configure the timer broadcast for each cpu, that must + * be done from the cpu context, so we use a smp cross + * call with 'on_each_cpu'. + */ + on_each_cpu(ux500_setup_broadcast_timer, NULL, 1); + + ret = cpuidle_register_driver(&ux500_idle_driver); + if (ret) { + printk(KERN_ERR "failed to register ux500 idle driver\n"); + return ret; + } + + for_each_online_cpu(cpu) { + device = &per_cpu(ux500_cpuidle_device, cpu); + device->cpu = cpu; + ret = cpuidle_register_device(device); + if (ret) { + printk(KERN_ERR "Failed to register cpuidle " + "device for cpu%d\n", cpu); + goto out_unregister; + } + } +out: + return ret; + +out_unregister: + for_each_online_cpu(cpu) { + device = &per_cpu(ux500_cpuidle_device, cpu); + cpuidle_unregister_device(device); + } + + cpuidle_unregister_driver(&ux500_idle_driver); + goto out; +} + +device_initcall(ux500_idle_init); |