From afefe67e0893325d75eb7b816dd394eef2eac628 Mon Sep 17 00:00:00 2001 From: Sai Prakash Ranjan Date: Tue, 10 Aug 2021 12:18:08 +0530 Subject: iommu/arm-smmu: Add clk_bulk_{prepare/unprepare} to system pm callbacks Some clocks for SMMU can have parent as XO such as gpu_cc_hub_cx_int_clk of GPU SMMU in QTI SC7280 SoC and in order to enter deep sleep states in such cases, we would need to drop the XO clock vote in unprepare call and this unprepare callback for XO is in RPMh (Resource Power Manager-Hardened) clock driver which controls RPMh managed clock resources for new QTI SoCs. Given we cannot have a sleeping calls such as clk_bulk_prepare() and clk_bulk_unprepare() in arm-smmu runtime pm callbacks since the iommu operations like map and unmap can be in atomic context and are in fast path, add this prepare and unprepare call to drop the XO vote only for system pm callbacks since it is not a fast path and we expect the system to enter deep sleep states with system pm as opposed to runtime pm. This is a similar sequence of clock requests (prepare,enable and disable,unprepare) in arm-smmu probe and remove. Signed-off-by: Sai Prakash Ranjan Co-developed-by: Rajendra Nayak Signed-off-by: Rajendra Nayak Link: https://lore.kernel.org/r/20210810064808.32486-1-saiprakash.ranjan@codeaurora.org Signed-off-by: Will Deacon --- drivers/iommu/arm/arm-smmu/arm-smmu.c | 26 +++++++++++++++++++++++--- 1 file changed, 23 insertions(+), 3 deletions(-) (limited to 'drivers/iommu/arm') diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c index f22dbeb1e510..fc8b932b47d4 100644 --- a/drivers/iommu/arm/arm-smmu/arm-smmu.c +++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c @@ -2281,18 +2281,38 @@ static int __maybe_unused arm_smmu_runtime_suspend(struct device *dev) static int __maybe_unused arm_smmu_pm_resume(struct device *dev) { + int ret; + struct arm_smmu_device *smmu = dev_get_drvdata(dev); + + ret = clk_bulk_prepare(smmu->num_clks, smmu->clks); + if (ret) + return ret; + if (pm_runtime_suspended(dev)) return 0; - return arm_smmu_runtime_resume(dev); + ret = arm_smmu_runtime_resume(dev); + if (ret) + clk_bulk_unprepare(smmu->num_clks, smmu->clks); + + return ret; } static int __maybe_unused arm_smmu_pm_suspend(struct device *dev) { + int ret = 0; + struct arm_smmu_device *smmu = dev_get_drvdata(dev); + if (pm_runtime_suspended(dev)) - return 0; + goto clk_unprepare; - return arm_smmu_runtime_suspend(dev); + ret = arm_smmu_runtime_suspend(dev); + if (ret) + return ret; + +clk_unprepare: + clk_bulk_unprepare(smmu->num_clks, smmu->clks); + return ret; } static const struct dev_pm_ops arm_smmu_pm_ops = { -- cgit v1.2.3