Re: [PATCH v2 3/4] dt-bindings: iommu/arm,smmu: add compatible string for Marvell

From: Robin Murphy
Date: Thu Aug 22 2019 - 10:16:34 EST


On 11/07/2019 16:02, Gregory CLEMENT wrote:
From: Hanna Hawa <hannah@xxxxxxxxxxx>

Add specific compatible string for Marvell usage due errata of
accessing 64bits registers of ARM SMMU, in AP806.

AP806 SoC uses the generic ARM-MMU500, and there's no specific
implementation of Marvell, this compatible is used for errata only.

Forgive me for repeating myself[1], but:

"Given that, I think something more specific like:

"marvell,ap806-smmu", "arm,mmu-500";

would be most appropriate. Otherwise, if some future Marvell SoC were to
ever come out with a *different* MMU-500 integration problem, you'd
already have painted yourself into a corner."

Robin.

[1] https://lore.kernel.org/linux-arm-kernel/3ce1d67a-4e3c-e8d8-f7fc-79649f1def68@xxxxxxx/

Signed-off-by: Hanna Hawa <hannah@xxxxxxxxxxx>
Signed-off-by: Gregory CLEMENT <gregory.clement@xxxxxxxxxxx>
---
Documentation/devicetree/bindings/iommu/arm,smmu.txt | 1 +
1 file changed, 1 insertion(+)

diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu.txt b/Documentation/devicetree/bindings/iommu/arm,smmu.txt
index 3133f3ba7567..7ed58d51846e 100644
--- a/Documentation/devicetree/bindings/iommu/arm,smmu.txt
+++ b/Documentation/devicetree/bindings/iommu/arm,smmu.txt
@@ -16,6 +16,7 @@ conditions.
"arm,mmu-400"
"arm,mmu-401"
"arm,mmu-500"
+ "marvell,mmu-500"
"cavium,smmu-v2"
"qcom,smmu-v2"