diff options
Diffstat (limited to 'arch/arm/mach-imx/cpuidle-imx6q.c')
-rw-r--r-- | arch/arm/mach-imx/cpuidle-imx6q.c | 73 |
1 files changed, 71 insertions, 2 deletions
diff --git a/arch/arm/mach-imx/cpuidle-imx6q.c b/arch/arm/mach-imx/cpuidle-imx6q.c index 83facc97b5d..d533e2695f0 100644 --- a/arch/arm/mach-imx/cpuidle-imx6q.c +++ b/arch/arm/mach-imx/cpuidle-imx6q.c @@ -6,21 +6,90 @@ * published by the Free Software Foundation. */ +#include <linux/clockchips.h> #include <linux/cpuidle.h> #include <linux/module.h> #include <asm/cpuidle.h> +#include <asm/proc-fns.h> +#include "common.h" #include "cpuidle.h" +static atomic_t master = ATOMIC_INIT(0); +static DEFINE_SPINLOCK(master_lock); + +static int imx6q_enter_wait(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) +{ + int cpu = dev->cpu; + + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &cpu); + + if (atomic_inc_return(&master) == num_online_cpus()) { + /* + * With this lock, we prevent other cpu to exit and enter + * this function again and become the master. + */ + if (!spin_trylock(&master_lock)) + goto idle; + imx6q_set_lpm(WAIT_UNCLOCKED); + cpu_do_idle(); + imx6q_set_lpm(WAIT_CLOCKED); + spin_unlock(&master_lock); + goto done; + } + +idle: + cpu_do_idle(); +done: + atomic_dec(&master); + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &cpu); + + return index; +} + +/* + * For each cpu, setup the broadcast timer because local timer + * stops for the states other than WFI. + */ +static void imx6q_setup_broadcast_timer(void *arg) +{ + int cpu = smp_processor_id(); + + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ON, &cpu); +} + static struct cpuidle_driver imx6q_cpuidle_driver = { .name = "imx6q_cpuidle", .owner = THIS_MODULE, .en_core_tk_irqen = 1, - .states[0] = ARM_CPUIDLE_WFI_STATE, - .state_count = 1, + .states = { + /* WFI */ + ARM_CPUIDLE_WFI_STATE, + /* WAIT */ + { + .exit_latency = 50, + .target_residency = 75, + .flags = CPUIDLE_FLAG_TIME_VALID, + .enter = imx6q_enter_wait, + .name = "WAIT", + .desc = "Clock off", + }, + }, + .state_count = 2, + .safe_state_index = 0, }; int __init imx6q_cpuidle_init(void) { + /* Need to enable SCU standby for entering WAIT modes */ + imx_scu_standby_enable(); + + /* Set chicken bit to get a reliable WAIT mode support */ + imx6q_set_chicken_bit(); + + /* Configure the broadcast timer on each cpu */ + on_each_cpu(imx6q_setup_broadcast_timer, NULL, 1); + return imx_cpuidle_init(&imx6q_cpuidle_driver); } |