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arm64: tegra: Disable ISO SMMU for Tegra194

PATCH Applied Jon Hunter 2 participants 2 messages Jan 13, 2022 – Jan 27, 2022

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Jon Hunter

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PATCH 1/1 arm64: tegra: Disable ISO SMMU for Tegra194

Commit e762232f9466 ("arm64: tegra: Add ISO SMMU controller for Tegra194") add the ISO SMMU for display devices on Tegra194. The SMMU is enabled by default but no hooked up to the display controllers yet because we do not have a way to pass frame-buffer memory from the bootloader to the kernel. However, even though the SMMU is not hooked up to the display controllers SMMU faults are being seen if a display is connected. Therefore, keep the ISO SMMU disabled by default for now.

Fixes e762232f9466 ("arm64: tegra: Add ISO SMMU controller for Tegra194")
Signed-off-by Jon Hunter <[email protected]>
---
 arch/arm64/boot/dts/nvidia/tegra194.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
arch/arm64/boot/dts/nvidia/tegra194.dtsi +1 -1
index 2d48c3715fc6..aaa00da5351d 100644
@@ -1584,7 +1584,7 @@ iommu@10000000 {
 			#iommu-cells = <1>;
 
 			nvidia,memory-controller = <&mc>;
-			status = "okay";
+			status = "disabled";
 		};
 
 		smmu: iommu@12000000 {
Signature · 1 line
2.25.1
Applied
#1 lore raw
Quoted 8 lines · Jon Hunter

Commit e762232f9466 ("arm64: tegra: Add ISO SMMU controller for Tegra194") add the ISO SMMU for display devices on Tegra194. The SMMU is enabled by default but no hooked up to the display controllers yet because we do not have a way to pass frame-buffer memory from the bootloader to the kernel. However, even though the SMMU is not hooked up to the display controllers SMMU faults are being seen if a display is connected. Therefore, keep the ISO SMMU disabled by default for now.

Quoted 5 lines
Fixes e762232f9466 ("arm64: tegra: Add ISO SMMU controller for Tegra194")
Signed-off-by Jon Hunter <[email protected]>
---
 arch/arm64/boot/dts/nvidia/tegra194.dtsi | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Applied, thanks.

Thierry