[PATCH 1/1] arm64: dts: marvell: keep SMMU disabled by default for Armada 7040 and 8040

Tomasz Nowicki tn at semihalf.com
Thu Nov 5 06:26:02 EST 2020


FW has to configure devices' StreamIDs so that SMMU is able to lookup
context and do proper translation later on. For Armada 7040 & 8040 and
publicly available FW, most of the devices are configured properly,
but some like ap_sdhci0, PCIe, NIC still remain unassigned which
results in SMMU faults about unmatched StreamID (assuming
ARM_SMMU_DISABLE_BYPASS_BY_DEFAUL=y).

Since there is dependency on custom FW let SMMU be disabled by default.
People who still willing to use SMMU need to enable manually and
use ARM_SMMU_DISABLE_BYPASS_BY_DEFAUL=n (or via kernel command line)
with extra caution.

Fixes: 83a3545d9c37 ("arm64: dts: marvell: add SMMU support")
Cc: <stable at vger.kernel.org> # 5.9+
Signed-off-by: Tomasz Nowicki <tn at semihalf.com>
---
 arch/arm64/boot/dts/marvell/armada-7040.dtsi | 4 ----
 arch/arm64/boot/dts/marvell/armada-8040.dtsi | 4 ----
 2 files changed, 8 deletions(-)

diff --git a/arch/arm64/boot/dts/marvell/armada-7040.dtsi b/arch/arm64/boot/dts/marvell/armada-7040.dtsi
index 7a3198cd7a07..2f440711d21d 100644
--- a/arch/arm64/boot/dts/marvell/armada-7040.dtsi
+++ b/arch/arm64/boot/dts/marvell/armada-7040.dtsi
@@ -15,10 +15,6 @@ / {
 		     "marvell,armada-ap806";
 };
 
-&smmu {
-	status = "okay";
-};
-
 &cp0_pcie0 {
 	iommu-map =
 		<0x0   &smmu 0x480 0x20>,
diff --git a/arch/arm64/boot/dts/marvell/armada-8040.dtsi b/arch/arm64/boot/dts/marvell/armada-8040.dtsi
index 79e8ce59baa8..22c2d6ebf381 100644
--- a/arch/arm64/boot/dts/marvell/armada-8040.dtsi
+++ b/arch/arm64/boot/dts/marvell/armada-8040.dtsi
@@ -15,10 +15,6 @@ / {
 		     "marvell,armada-ap806";
 };
 
-&smmu {
-	status = "okay";
-};
-
 &cp0_pcie0 {
 	iommu-map =
 		<0x0   &smmu 0x480 0x20>,
-- 
2.25.1




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