When CPU-idle is enabled, the MPU sub-system will transition to low power states during idle periods. If the PMU is active and the MPU sub-system transitions to a low power state, such as retention, then the PMU context will be lost and PMU events will stop. To prevent this from happening add a QoS constraint whenever PMU is active to prevent the MPU sub-system from transitioning to a low power state.
By default the PMU QoS constraint is set to -1 so it will not prevent any low power states and when the PMU is enabled, it is set to 0, so that only C-state C0 is allowed. Cc: Ming Lei <[email protected]> Cc: Will Deacon <[email protected]> Cc: Benoit Cousson <[email protected]> Cc: Paul Walmsley <[email protected]> Cc: Kevin Hilman <[email protected]> Signed-off-by: Jon Hunter <[email protected]> --- arch/arm/mach-omap2/pmu.c | 52 ++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 49 insertions(+), 3 deletions(-) diff --git a/arch/arm/mach-omap2/pmu.c b/arch/arm/mach-omap2/pmu.c index f1b535a..e457f0e 100644 --- a/arch/arm/mach-omap2/pmu.c +++ b/arch/arm/mach-omap2/pmu.c @@ -13,6 +13,7 @@ * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. */ +#include <linux/pm_qos.h> #include <linux/pm_runtime.h> #include <asm/pmu.h> @@ -21,11 +22,40 @@ #include <plat/omap_hwmod.h> #include <plat/omap_device.h> +static struct pm_qos_request pmu_pm_qos_request; static struct arm_pmu_platdata omap_pmu_data; static struct platform_device *omap_pmu_dev; static struct cti omap4_cti[2]; /* + * omap_pmu_runtime_resume - PMU runtime resume callback + * + * Platform specific PMU runtime resume callback for OMAP devices to + * configure the cross trigger interface for routing PMU interrupts. + * This is called by the PM runtime framework. + */ +static int omap_pmu_runtime_resume(struct device *dev) +{ + pm_qos_update_request(&pmu_pm_qos_request, 0); + + return 0; +} + +/* + * omap_pmu_runtime_suspend - PMU runtime suspend callback + * + * Platform specific PMU runtime suspend callback for OMAP devices to + * disable the cross trigger interface interrupts. This is called by + * the PM runtime framework. + */ +static int omap_pmu_runtime_suspend(struct device *dev) +{ + pm_qos_update_request(&pmu_pm_qos_request, PM_QOS_DEFAULT_VALUE); + + return 0; +} + +/* * omap2_init_pmu - creates and registers PMU platform device * * Uses OMAP HWMOD framework to create and register an ARM PMU device. @@ -45,7 +75,11 @@ static int __init omap2_init_pmu(void) return -ENODEV; } - omap_pmu_dev = omap_device_build(dev_name, id, oh, NULL, 0, NULL, 0, 0); + omap_pmu_data.runtime_resume = omap_pmu_runtime_resume; + omap_pmu_data.runtime_suspend = omap_pmu_runtime_suspend; + + omap_pmu_dev = omap_device_build(dev_name, id, oh, &omap_pmu_data, + sizeof(omap_pmu_data), NULL, 0, 0); WARN(IS_ERR(omap_pmu_dev), "Can't build omap_device for %s.\n", dev_name); @@ -65,6 +99,8 @@ static int __init omap2_init_pmu(void) */ static int omap4_pmu_runtime_resume(struct device *dev) { + pm_qos_update_request(&pmu_pm_qos_request, 0); + /* configure CTI0 for PMU IRQ routing */ cti_unlock(&omap4_cti[0]); cti_map_trigger(&omap4_cti[0], 1, 6, 2); @@ -90,6 +126,8 @@ static int omap4_pmu_runtime_suspend(struct device *dev) cti_disable(&omap4_cti[0]); cti_disable(&omap4_cti[1]); + pm_qos_update_request(&pmu_pm_qos_request, PM_QOS_DEFAULT_VALUE); + return 0; } @@ -189,6 +227,8 @@ static int __init omap4430_init_pmu(void) static int __init omap_init_pmu(void) { + int r; + /* * OMAP4460/70 devices may use the omap2_init_pmu() function because * these devices have dedicated PMU IRQs and only need the MPU @@ -197,9 +237,15 @@ static int __init omap_init_pmu(void) * sub-systems to be enabled. */ if (cpu_is_omap443x()) - return omap4430_init_pmu(); + r = omap4430_init_pmu(); else - return omap2_init_pmu(); + r = omap2_init_pmu(); + + if (!r) + pm_qos_add_request(&pmu_pm_qos_request, PM_QOS_CPU_DMA_LATENCY, + PM_QOS_DEFAULT_VALUE); + + return r; } subsys_initcall(omap_init_pmu); -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
