Re: [PATCH v3 7/7] arm64: dts: qcom: sa8775p: add the GPU IOMMU node

From: Bartosz Golaszewski
Date: Tue Apr 11 2023 - 10:42:08 EST


On Tue, Apr 11, 2023 at 3:16 PM Konrad Dybcio <konrad.dybcio@xxxxxxxxxx> wrote:
>
>
>
> On 11.04.2023 14:59, Bartosz Golaszewski wrote:
> > From: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
> >
> > Add the Adreno GPU IOMMU for sa8775p-based platforms.
> >
> > Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
> > ---
> > arch/arm64/boot/dts/qcom/sa8775p.dtsi | 37 +++++++++++++++++++++++++++
> > 1 file changed, 37 insertions(+)
> >
> > diff --git a/arch/arm64/boot/dts/qcom/sa8775p.dtsi b/arch/arm64/boot/dts/qcom/sa8775p.dtsi
> > index 191b510b5a1a..11f3d80dd869 100644
> > --- a/arch/arm64/boot/dts/qcom/sa8775p.dtsi
> > +++ b/arch/arm64/boot/dts/qcom/sa8775p.dtsi
> > @@ -7,6 +7,7 @@
> > #include <dt-bindings/interrupt-controller/arm-gic.h>
> > #include <dt-bindings/clock/qcom,rpmh.h>
> > #include <dt-bindings/clock/qcom,sa8775p-gcc.h>
> > +#include <dt-bindings/clock/qcom,sa8775p-gpucc.h>
> > #include <dt-bindings/interconnect/qcom,sa8775p-rpmh.h>
> > #include <dt-bindings/power/qcom-rpmpd.h>
> > #include <dt-bindings/soc/qcom,rpmh-rsc.h>
> > @@ -605,6 +606,42 @@ gpucc: clock-controller@3d90000 {
> > #power-domain-cells = <1>;
> > };
> >
> > + adreno_smmu: iommu@3da0000 {
> > + compatible = "qcom,sa8775p-smmu-500", "qcom,adreno-smmu",
> > + "arm,mmu-500";
> Err.. does it even boot like this? You dropped the qcom,smmu-500 compatible
> which means it's getting bound to the generic SMMU driver (without
> QC quirks). If that was a mistake, you should have had all 4
>
> "qcom,sa8775p-smmu-500", qcom,adreno-smmu, "qcom,smmu-500", "arm,mmu-500"
>
> Without falling into the qc-specific codepaths, the Adreno compat does
> nothing.
>

I did that initially, then noticed dtbs_check fails because the
existing adreno GPUs implementing "arm,smmu-500" expect three
compatibles like in this commit. I did that and the driver still
probed the same so I assumed all's good. You're right of course, the
adreno impl is not being assigned without "qcom,smmu-500". Are the
bindings wrong in this case and should it be something like the
following?

diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
b/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
index d966dc65ce10..cd1b052a7242 100644
--- a/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
+++ b/Documentation/devicetree/bindings/iommu/arm,smmu.yaml
@@ -84,6 +84,7 @@ properties:
- qcom,sm8150-smmu-500
- qcom,sm8250-smmu-500
- const: qcom,adreno-smmu
+ - const: qcom,smmu-500
- const: arm,mmu-500
- description: Qcom Adreno GPUs implementing "arm,smmu-v2"
items:

Bartosz

> Konrad
> > + reg = <0x0 0x03da0000 0x0 0x20000>;
> > + #iommu-cells = <2>;
> > + #global-interrupts = <2>;
> > + dma-coherent;
> > + power-domains = <&gpucc GPU_CC_CX_GDSC>;
> > + clocks = <&gcc GCC_GPU_MEMNOC_GFX_CLK>,
> > + <&gcc GCC_GPU_SNOC_DVM_GFX_CLK>,
> > + <&gpucc GPU_CC_AHB_CLK>,
> > + <&gpucc GPU_CC_HLOS1_VOTE_GPU_SMMU_CLK>,
> > + <&gpucc GPU_CC_CX_GMU_CLK>,
> > + <&gpucc GPU_CC_HUB_CX_INT_CLK>,
> > + <&gpucc GPU_CC_HUB_AON_CLK>;
> > + clock-names = "gcc_gpu_memnoc_gfx_clk",
> > + "gcc_gpu_snoc_dvm_gfx_clk",
> > + "gpu_cc_ahb_clk",
> > + "gpu_cc_hlos1_vote_gpu_smmu_clk",
> > + "gpu_cc_cx_gmu_clk",
> > + "gpu_cc_hub_cx_int_clk",
> > + "gpu_cc_hub_aon_clk";
> > + interrupts = <GIC_SPI 673 IRQ_TYPE_LEVEL_HIGH>,
> > + <GIC_SPI 674 IRQ_TYPE_LEVEL_HIGH>,
> > + <GIC_SPI 678 IRQ_TYPE_LEVEL_HIGH>,
> > + <GIC_SPI 679 IRQ_TYPE_LEVEL_HIGH>,
> > + <GIC_SPI 680 IRQ_TYPE_LEVEL_HIGH>,
> > + <GIC_SPI 681 IRQ_TYPE_LEVEL_HIGH>,
> > + <GIC_SPI 682 IRQ_TYPE_LEVEL_HIGH>,
> > + <GIC_SPI 683 IRQ_TYPE_LEVEL_HIGH>,
> > + <GIC_SPI 684 IRQ_TYPE_LEVEL_HIGH>,
> > + <GIC_SPI 685 IRQ_TYPE_LEVEL_HIGH>,
> > + <GIC_SPI 686 IRQ_TYPE_LEVEL_HIGH>,
> > + <GIC_SPI 687 IRQ_TYPE_LEVEL_HIGH>;
> > + };
> > +
> > pdc: interrupt-controller@b220000 {
> > compatible = "qcom,sa8775p-pdc", "qcom,pdc";
> > reg = <0x0 0x0b220000 0x0 0x30000>,