The smmu needs to be functional only when the respective master's using it are active. The device_link feature helps to track such functional dependencies, so that the iommu gets powered when the master device enables itself using pm_runtime. So by adapting the smmu driver for runtime pm, above said dependency can be addressed. This patch adds the pm runtime/sleep callbacks to the driver and also the functions to parse the smmu clocks from DT and enable them in resume/suspend. Signed-off-by: Sricharan R <sricharan@xxxxxxxxxxxxxx> --- drivers/iommu/arm-smmu.c | 74 ++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 65 insertions(+), 9 deletions(-) diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index abf6496..f7e11d3 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -48,6 +48,7 @@ #include <linux/of_iommu.h> #include <linux/pci.h> #include <linux/platform_device.h> +#include <linux/pm_runtime.h> #include <linux/slab.h> #include <linux/spinlock.h> @@ -340,6 +341,13 @@ struct arm_smmu_master_cfg { #define for_each_cfg_sme(fw, i, idx) \ for (i = 0; idx = fwspec_smendx(fw, i), i < fw->num_ids; ++i) +struct arm_smmu_clks { + void *clks; + int (*init_clocks)(struct arm_smmu_device *smmu); + int (*enable_clocks)(struct arm_smmu_device *smmu); + void (*disable_clocks)(struct arm_smmu_device *smmu); +}; + struct arm_smmu_device { struct device *dev; @@ -387,7 +395,7 @@ struct arm_smmu_device { u32 num_global_irqs; u32 num_context_irqs; unsigned int *irqs; - + struct arm_smmu_clks smmu_clks; u32 cavium_id_base; /* Specific to Cavium */ /* IOMMU core code handle */ @@ -1958,16 +1966,24 @@ static int arm_smmu_device_cfg_probe(struct arm_smmu_device *smmu) struct arm_smmu_match_data { enum arm_smmu_arch_version version; enum arm_smmu_implementation model; + struct arm_smmu_clks smmu_clks; }; -#define ARM_SMMU_MATCH_DATA(name, ver, imp) \ -static struct arm_smmu_match_data name = { .version = ver, .model = imp } - -ARM_SMMU_MATCH_DATA(smmu_generic_v1, ARM_SMMU_V1, GENERIC_SMMU); -ARM_SMMU_MATCH_DATA(smmu_generic_v2, ARM_SMMU_V2, GENERIC_SMMU); -ARM_SMMU_MATCH_DATA(arm_mmu401, ARM_SMMU_V1_64K, GENERIC_SMMU); -ARM_SMMU_MATCH_DATA(arm_mmu500, ARM_SMMU_V2, ARM_MMU500); -ARM_SMMU_MATCH_DATA(cavium_smmuv2, ARM_SMMU_V2, CAVIUM_SMMUV2); +#define ARM_SMMU_MATCH_DATA(name, ver, imp, init, enable, disable) \ +static struct arm_smmu_match_data name = { .version = ver, .model = imp, \ + .smmu_clks.init_clocks = init, \ + .smmu_clks.enable_clocks = enable, \ + .smmu_clks.disable_clocks = disable } + +ARM_SMMU_MATCH_DATA(smmu_generic_v1, ARM_SMMU_V1, GENERIC_SMMU, + NULL, NULL, NULL); +ARM_SMMU_MATCH_DATA(smmu_generic_v2, ARM_SMMU_V2, GENERIC_SMMU, + NULL, NULL, NULL); +ARM_SMMU_MATCH_DATA(arm_mmu401, ARM_SMMU_V1_64K, GENERIC_SMMU, + NULL, NULL, NULL); +ARM_SMMU_MATCH_DATA(arm_mmu500, ARM_SMMU_V2, ARM_MMU500, NULL, NULL, NULL); +ARM_SMMU_MATCH_DATA(cavium_smmuv2, ARM_SMMU_V2, CAVIUM_SMMUV2, + NULL, NULL, NULL); static const struct of_device_id arm_smmu_of_match[] = { { .compatible = "arm,smmu-v1", .data = &smmu_generic_v1 }, @@ -2054,6 +2070,7 @@ static int arm_smmu_device_dt_probe(struct platform_device *pdev, data = of_device_get_match_data(dev); smmu->version = data->version; smmu->model = data->model; + smmu->smmu_clks = data->smmu_clks; parse_driver_options(smmu); @@ -2135,6 +2152,13 @@ static int arm_smmu_device_probe(struct platform_device *pdev) smmu->irqs[i] = irq; } + if (smmu->smmu_clks.init_clocks) { + err = smmu->smmu_clks.init_clocks(smmu); + if (err) + return err; + } + + pm_runtime_enable(dev); err = arm_smmu_device_cfg_probe(smmu); if (err) return err; @@ -2211,10 +2235,42 @@ static int arm_smmu_device_remove(struct platform_device *pdev) return 0; } +#ifdef CONFIG_PM +static int arm_smmu_resume(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct arm_smmu_device *smmu = platform_get_drvdata(pdev); + int ret = 0; + + if (smmu->smmu_clks.enable_clocks) + ret = smmu->smmu_clks.enable_clocks(smmu); + + return ret; +} + +static int arm_smmu_suspend(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct arm_smmu_device *smmu = platform_get_drvdata(pdev); + + if (smmu->smmu_clks.disable_clocks) + smmu->smmu_clks.disable_clocks(smmu); + + return 0; +} +#endif + +static const struct dev_pm_ops arm_smmu_pm_ops = { + SET_RUNTIME_PM_OPS(arm_smmu_suspend, arm_smmu_resume, NULL) + SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, + pm_runtime_force_resume) +}; + static struct platform_driver arm_smmu_driver = { .driver = { .name = "arm-smmu", .of_match_table = of_match_ptr(arm_smmu_of_match), + .pm = &arm_smmu_pm_ops, }, .probe = arm_smmu_device_probe, .remove = arm_smmu_device_remove, -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html