From 96a299d24cfb6b9659304131b598fa09f4c9041e Mon Sep 17 00:00:00 2001 From: Sricharan R Date: Tue, 4 Dec 2018 11:52:09 +0530 Subject: [PATCH] iommu/arm-smmu: Add pm_runtime/sleep ops 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 the corresponding bulk clock handling for all the clocks needed by smmu. Also, while we enable the runtime pm, add a pm sleep suspend callback that pushes devices to low power state by turning the clocks off in a system sleep. Add corresponding clock enable path in resume callback as well. Signed-off-by: Sricharan R Signed-off-by: Archit Taneja [Thor: Rework to get clocks from device tree] Signed-off-by: Thor Thayer [vivek: rework for clock and pm ops] Signed-off-by: Vivek Gautam Reviewed-by: Tomasz Figa Tested-by: Srinivas Kandagatla Reviewed-by: Robin Murphy Tested-by: Thor Thayer Signed-off-by: Will Deacon --- drivers/iommu/arm-smmu.c | 58 +++++++++++++++++++++++++++++++++++++--- 1 file changed, 55 insertions(+), 3 deletions(-) diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index 5a28ae892504..602b67d4f2d6 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -48,6 +48,7 @@ #include #include #include +#include #include #include @@ -206,6 +207,8 @@ struct arm_smmu_device { u32 num_global_irqs; u32 num_context_irqs; unsigned int *irqs; + struct clk_bulk_data *clks; + int num_clks; u32 cavium_id_base; /* Specific to Cavium */ @@ -1947,7 +1950,7 @@ struct arm_smmu_match_data { }; #define ARM_SMMU_MATCH_DATA(name, ver, imp) \ -static struct arm_smmu_match_data name = { .version = ver, .model = imp } +static const 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); @@ -2150,6 +2153,17 @@ static int arm_smmu_device_probe(struct platform_device *pdev) smmu->irqs[i] = irq; } + err = devm_clk_bulk_get_all(dev, &smmu->clks); + if (err < 0) { + dev_err(dev, "failed to get clocks %d\n", err); + return err; + } + smmu->num_clks = err; + + err = clk_bulk_prepare_enable(smmu->num_clks, smmu->clks); + if (err) + return err; + err = arm_smmu_device_cfg_probe(smmu); if (err) return err; @@ -2236,6 +2250,9 @@ static int arm_smmu_device_remove(struct platform_device *pdev) /* Turn the thing off */ writel(sCR0_CLIENTPD, ARM_SMMU_GR0_NS(smmu) + ARM_SMMU_GR0_sCR0); + + clk_bulk_disable_unprepare(smmu->num_clks, smmu->clks); + return 0; } @@ -2244,15 +2261,50 @@ static void arm_smmu_device_shutdown(struct platform_device *pdev) arm_smmu_device_remove(pdev); } -static int __maybe_unused arm_smmu_pm_resume(struct device *dev) +static int __maybe_unused arm_smmu_runtime_resume(struct device *dev) { struct arm_smmu_device *smmu = dev_get_drvdata(dev); + int ret; + + ret = clk_bulk_enable(smmu->num_clks, smmu->clks); + if (ret) + return ret; arm_smmu_device_reset(smmu); + return 0; } -static SIMPLE_DEV_PM_OPS(arm_smmu_pm_ops, NULL, arm_smmu_pm_resume); +static int __maybe_unused arm_smmu_runtime_suspend(struct device *dev) +{ + struct arm_smmu_device *smmu = dev_get_drvdata(dev); + + clk_bulk_disable(smmu->num_clks, smmu->clks); + + return 0; +} + +static int __maybe_unused arm_smmu_pm_resume(struct device *dev) +{ + if (pm_runtime_suspended(dev)) + return 0; + + return arm_smmu_runtime_resume(dev); +} + +static int __maybe_unused arm_smmu_pm_suspend(struct device *dev) +{ + if (pm_runtime_suspended(dev)) + return 0; + + return arm_smmu_runtime_suspend(dev); +} + +static const struct dev_pm_ops arm_smmu_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(arm_smmu_pm_suspend, arm_smmu_pm_resume) + SET_RUNTIME_PM_OPS(arm_smmu_runtime_suspend, + arm_smmu_runtime_resume, NULL) +}; static struct platform_driver arm_smmu_driver = { .driver = {