Re: [PATCH v5 1/7] dt-bindings: iommu: Add Qualcomm TBU bindings
From: Georgi Djakov <djakov@kernel.org>
Date: 2024-02-29 20:17:30
Also in:
linux-arm-msm, linux-devicetree, linux-iommu, lkml
Hi Krzysztof, On 29.02.24 19:59, Krzysztof Kozlowski wrote:
On 26/02/2024 18:22, Georgi Djakov wrote:quoted
The "apps_smmu" on the Qualcomm sdm845 platform is an implementation of the SMMU-500, that consists of a single TCU (Translation Control Unit) and multiple TBUs (Translation Buffer Units). These TBUs have hardware debugging features that are specific and only present on Qualcomm hardware. Represent them as independent DT nodes. List all the resources that are needed to operate them (such as registers, clocks, power domains and interconnects). Signed-off-by: Georgi Djakov <redacted> --- .../devicetree/bindings/iommu/qcom,tbu.yaml | 65 +++++++++++++++++++ 1 file changed, 65 insertions(+) create mode 100644 Documentation/devicetree/bindings/iommu/qcom,tbu.yamlHeh, I wonder how did you solve Robin's comments. I don't see you responding to Robin. Just v5 sent...
Yeah, i didn't respond because his response was clear to me. He responded to the fundamental question whether to model the TBUs as child DT nodes of the SMMU or as standalone nodes. So in the first versions of this patchset we tried to explore the path with "child" nodes and search if there are any other implementation than the Qualcomm one and try to find some common binding... and Robin's objection was exactly to that. It seems that adding more functionalities in TBUs (which requires resource management) is only a Qualcomm thing and common binding does not make sense, so now we are going with standalone DT nodes as he suggested. Thanks, Georgi _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel