[PATCH 6.6 136/538] iommu/arm-smmu-qcom: apply num_context_bank fixes for SDM630 / SDM660

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



6.6-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>

[ Upstream commit 19eb465c969f3d6ed1b98506d3e470e863b41e16 ]

The Qualcomm SDM630 / SDM660 platform requires the same kind of
workaround as MSM8998: some IOMMUs have context banks reserved by
firmware / TZ, touching those banks resets the board.

Apply the num_context_bank workaround to those two SMMU devices in order
to allow them to be used by Linux.

Fixes: b812834b5329 ("iommu: arm-smmu-qcom: Add sdm630/msm8998 compatibles for qcom quirks")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
Reviewed-by: Bjorn Andersson <andersson@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20240907-sdm660-wifi-v1-1-e316055142f8@xxxxxxxxxx
Signed-off-by: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
index db2092d5af5eb..d491589360197 100644
--- a/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
+++ b/drivers/iommu/arm/arm-smmu/arm-smmu-qcom.c
@@ -282,8 +282,15 @@ static int qcom_smmu_cfg_probe(struct arm_smmu_device *smmu)
 	 * MSM8998 LPASS SMMU reports 13 context banks, but accessing
 	 * the last context bank crashes the system.
 	 */
-	if (of_device_is_compatible(smmu->dev->of_node, "qcom,msm8998-smmu-v2") && smmu->num_context_banks == 13)
+	if (of_device_is_compatible(smmu->dev->of_node, "qcom,msm8998-smmu-v2") &&
+	    smmu->num_context_banks == 13) {
 		smmu->num_context_banks = 12;
+	} else if (of_device_is_compatible(smmu->dev->of_node, "qcom,sdm630-smmu-v2")) {
+		if (smmu->num_context_banks == 21) /* SDM630 / SDM660 A2NOC SMMU */
+			smmu->num_context_banks = 7;
+		else if (smmu->num_context_banks == 14) /* SDM630 / SDM660 LPASS SMMU */
+			smmu->num_context_banks = 13;
+	}
 
 	/*
 	 * Some platforms support more than the Arm SMMU architected maximum of
@@ -346,6 +353,11 @@ static int qcom_adreno_smmuv2_cfg_probe(struct arm_smmu_device *smmu)
 	/* Support for 16K pages is advertised on some SoCs, but it doesn't seem to work */
 	smmu->features &= ~ARM_SMMU_FEAT_FMT_AARCH64_16K;
 
+	/* TZ protects several last context banks, hide them from Linux */
+	if (of_device_is_compatible(smmu->dev->of_node, "qcom,sdm630-smmu-v2") &&
+	    smmu->num_context_banks == 5)
+		smmu->num_context_banks = 2;
+
 	return 0;
 }
 
-- 
2.43.0







[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux