[PATCH] iommu/qcom: restore IOMMU state if needed
From: Luca Weiss <hidden>
Date: 2023-10-11 17:57:39
Also in:
linux-arm-msm, linux-iommu, lkml, phone-devel
Subsystem:
arm smmu drivers, arm/qualcomm mailing list, iommu subsystem, qualcomm iommu, the rest · Maintainers:
Will Deacon, Joerg Roedel, Rob Clark, Linus Torvalds
From: Vladimir Lypak <redacted> If the IOMMU has a power domain then some state will be lost in qcom_iommu_suspend and TZ will reset device if we don't call qcom_scm_restore_sec_cfg before accessing it again. Signed-off-by: Vladimir Lypak <redacted> [luca@z3ntu.xyz: reword commit message a bit] Signed-off-by: Luca Weiss <redacted> --- This patch is required for MSM8953 GPU IOMMU. See also downstream sources: https://git.codelinaro.org/clo/la/kernel/msm-4.9/-/commit/f8464885dafc5b780b85de29d92a08c692d3a4d0 https://git.codelinaro.org/clo/la/kernel/msm-4.9/-/blob/LA.UM.10.6.2.r1-02500-89xx.0/drivers/iommu/arm-smmu.c#L4221-4225 Since the compatibles provided by this driver (qcom,msm-iommu-v*) is only used on msm8916, msm8939 and msm8953, and both 8916 and 8939 don't have a power domain on the IOMMU, I also don't expect anything to break there. --- drivers/iommu/arm/arm-smmu/qcom_iommu.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/drivers/iommu/arm/arm-smmu/qcom_iommu.c b/drivers/iommu/arm/arm-smmu/qcom_iommu.c
index 97b2122032b2..67abeb02cf53 100644
--- a/drivers/iommu/arm/arm-smmu/qcom_iommu.c
+++ b/drivers/iommu/arm/arm-smmu/qcom_iommu.c@@ -900,8 +900,16 @@ static void qcom_iommu_device_remove(struct platform_device *pdev) static int __maybe_unused qcom_iommu_resume(struct device *dev) { struct qcom_iommu_dev *qcom_iommu = dev_get_drvdata(dev); + int ret; + + ret = clk_bulk_prepare_enable(CLK_NUM, qcom_iommu->clks); + if (ret < 0) + return ret; + + if (dev->pm_domain) + return qcom_scm_restore_sec_cfg(qcom_iommu->sec_id, 0); - return clk_bulk_prepare_enable(CLK_NUM, qcom_iommu->clks); + return ret; } static int __maybe_unused qcom_iommu_suspend(struct device *dev)
--- base-commit: 2933a1156742d8c47550493a77af8e2d81cf3c84 change-id: 20231011-msm8953-iommu-restore-fabc2e31fee7 Best regards, -- Luca Weiss [off-list ref] _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel