| Message ID | 1518173826-11759-1-git-send-email-vivek.gautam@codeaurora.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Vivek, Thanks for the patch. Please see my comments inline. On Fri, Feb 9, 2018 at 7:57 PM, Vivek Gautam <vivek.gautam@codeaurora.org> wrote: > qcom,smmu-v2 is an arm,smmu-v2 implementation with specific > clock and power requirements. This smmu core is used with > multiple masters on msm8996, viz. mdss, video, etc. > Add bindings for the same. > > Signed-off-by: Vivek Gautam <vivek.gautam@codeaurora.org> > Reviewed-by: Rob Herring <robh@kernel.org> > --- > > Changes in v8: > - Added the missing IOMMU_OF_DECLARE declaration for "qcom,smmu-v2" > > .../devicetree/bindings/iommu/arm,smmu.txt | 43 ++++++++++++++++++++++ > drivers/iommu/arm-smmu.c | 14 +++++++ > 2 files changed, 57 insertions(+) > > diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu.txt b/Documentation/devicetree/bindings/iommu/arm,smmu.txt > index 8a6ffce12af5..169222ae2706 100644 > --- a/Documentation/devicetree/bindings/iommu/arm,smmu.txt > +++ b/Documentation/devicetree/bindings/iommu/arm,smmu.txt > @@ -17,10 +17,19 @@ conditions. > "arm,mmu-401" > "arm,mmu-500" > "cavium,smmu-v2" > + "qcom,<soc>-smmu-v2", "qcom,smmu-v2" > > depending on the particular implementation and/or the > version of the architecture implemented. > > + A number of Qcom SoCs use qcom,smmu-v2 version of the IP. > + "qcom,<soc>-smmu-v2" represents a soc specific compatible > + string that should be present along with the "qcom,smmu-v2" > + to facilitate SoC specific clocks/power connections and to > + address specific bug fixes. > + An example string would be - > + "qcom,msm8996-smmu-v2", "qcom,smmu-v2". Hmm, I remember that for <soc> and similar wildcards we required explicitly listing allowed values. Rob, has it changed since I stumbled upon such thing last time (or I just got it wrong before)? > + > - reg : Base address and size of the SMMU. > > - #global-interrupts : The number of global interrupts exposed by the > @@ -71,6 +80,23 @@ conditions. > or using stream matching with #iommu-cells = <2>, and > may be ignored if present in such cases. > > +- clock-names: Should be "bus", and "iface" for "qcom,smmu-v2" > + implementation. > + > + "bus" clock for "qcom,smmu-v2" is required for downstream > + bus access and for the smmu ptw. > + > + "iface" clock is required to access smmu's registers through > + the TCU's programming interface. nit: Could we have it in a bit more structured way? E.g. - clock-names: List of names of clocks input to the device. The required list depends on particular implementation and is as follows: - for "qcom,smmu-v2": - "bus": clock required for downstream bus access and for the smmu ptw, - "iface": clock required to access smmu's registers through the TCU's programming interface. - unspecified for other implementations. (+/- wrapping) > + > +- clocks: Phandles for respective clocks described by clock-names. Phandle is just a pointer to another node. Clocks are however specified using a phandle and a number of arguments, depending on the clock controller. I'd change it to: - clocks: Specifiers for all clocks listed in the clock-names property, as per generic clock bindings. > + > +- power-domains: Phandles to SMMU's power domain specifier. This is > + required even if SMMU belongs to the master's power > + domain, as the SMMU will have to be enabled and > + accessed before master gets enabled and linked to its > + SMMU. From DT point of view, the relationship of SMMU belonging to a master device doesn't exist. The power-domains property needs to be properly specified for all devices within power domains represented in DT, with an exception of the case when the parent-child relationship is explicitly stated in DT by child devices being represented by child nodes of the parent device node. - power-domains: Specifiers for power domains required to be powered on for the SMMU to operate, as per generic power domain bindings. Best regards, Tomasz
diff --git a/Documentation/devicetree/bindings/iommu/arm,smmu.txt b/Documentation/devicetree/bindings/iommu/arm,smmu.txt index 8a6ffce12af5..169222ae2706 100644 --- a/Documentation/devicetree/bindings/iommu/arm,smmu.txt +++ b/Documentation/devicetree/bindings/iommu/arm,smmu.txt @@ -17,10 +17,19 @@ conditions. "arm,mmu-401" "arm,mmu-500" "cavium,smmu-v2" + "qcom,<soc>-smmu-v2", "qcom,smmu-v2" depending on the particular implementation and/or the version of the architecture implemented. + A number of Qcom SoCs use qcom,smmu-v2 version of the IP. + "qcom,<soc>-smmu-v2" represents a soc specific compatible + string that should be present along with the "qcom,smmu-v2" + to facilitate SoC specific clocks/power connections and to + address specific bug fixes. + An example string would be - + "qcom,msm8996-smmu-v2", "qcom,smmu-v2". + - reg : Base address and size of the SMMU. - #global-interrupts : The number of global interrupts exposed by the @@ -71,6 +80,23 @@ conditions. or using stream matching with #iommu-cells = <2>, and may be ignored if present in such cases. +- clock-names: Should be "bus", and "iface" for "qcom,smmu-v2" + implementation. + + "bus" clock for "qcom,smmu-v2" is required for downstream + bus access and for the smmu ptw. + + "iface" clock is required to access smmu's registers through + the TCU's programming interface. + +- clocks: Phandles for respective clocks described by clock-names. + +- power-domains: Phandles to SMMU's power domain specifier. This is + required even if SMMU belongs to the master's power + domain, as the SMMU will have to be enabled and + accessed before master gets enabled and linked to its + SMMU. + ** Deprecated properties: - mmu-masters (deprecated in favour of the generic "iommus" binding) : @@ -137,3 +163,20 @@ conditions. iommu-map = <0 &smmu3 0 0x400>; ... }; + + /* Qcom's arm,smmu-v2 implementation */ + smmu4: iommu { + compatible = "qcom,msm8996-smmu-v2", "qcom,smmu-v2"; + reg = <0xd00000 0x10000>; + + #global-interrupts = <1>; + interrupts = <GIC_SPI 73 IRQ_TYPE_LEVEL_HIGH>, + <GIC_SPI 320 IRQ_TYPE_LEVEL_HIGH>, + <GIC_SPI 321 IRQ_TYPE_LEVEL_HIGH>; + #iommu-cells = <1>; + power-domains = <&mmcc MDSS_GDSC>; + + clocks = <&mmcc SMMU_MDP_AXI_CLK>, + <&mmcc SMMU_MDP_AHB_CLK>; + clock-names = "bus", "iface"; + }; diff --git a/drivers/iommu/arm-smmu.c b/drivers/iommu/arm-smmu.c index c7e924d553bd..40da3f251acf 100644 --- a/drivers/iommu/arm-smmu.c +++ b/drivers/iommu/arm-smmu.c @@ -119,6 +119,7 @@ enum arm_smmu_implementation { GENERIC_SMMU, ARM_MMU500, CAVIUM_SMMUV2, + QCOM_SMMUV2, }; struct arm_smmu_s2cr { @@ -1950,6 +1951,17 @@ struct arm_smmu_match_data { ARM_SMMU_MATCH_DATA(arm_mmu500, ARM_SMMU_V2, ARM_MMU500); ARM_SMMU_MATCH_DATA(cavium_smmuv2, ARM_SMMU_V2, CAVIUM_SMMUV2); +static const char * const qcom_smmuv2_clks[] = { + "bus", "iface", +}; + +static const struct arm_smmu_match_data qcom_smmuv2 = { + .version = ARM_SMMU_V2, + .model = QCOM_SMMUV2, + .clks = qcom_smmuv2_clks, + .num_clks = ARRAY_SIZE(qcom_smmuv2_clks), +}; + static const struct of_device_id arm_smmu_of_match[] = { { .compatible = "arm,smmu-v1", .data = &smmu_generic_v1 }, { .compatible = "arm,smmu-v2", .data = &smmu_generic_v2 }, @@ -1957,6 +1969,7 @@ struct arm_smmu_match_data { { .compatible = "arm,mmu-401", .data = &arm_mmu401 }, { .compatible = "arm,mmu-500", .data = &arm_mmu500 }, { .compatible = "cavium,smmu-v2", .data = &cavium_smmuv2 }, + { .compatible = "qcom,smmu-v2", .data = &qcom_smmuv2 }, { }, }; MODULE_DEVICE_TABLE(of, arm_smmu_of_match); @@ -2319,6 +2332,7 @@ static int __maybe_unused arm_smmu_runtime_suspend(struct device *dev) IOMMU_OF_DECLARE(arm_mmu401, "arm,mmu-401"); IOMMU_OF_DECLARE(arm_mmu500, "arm,mmu-500"); IOMMU_OF_DECLARE(cavium_smmuv2, "cavium,smmu-v2"); +IOMMU_OF_DECLARE(qcom_smmuv2, "qcom,smmu-v2"); MODULE_DESCRIPTION("IOMMU API for ARM architected SMMU implementations"); MODULE_AUTHOR("Will Deacon <will.deacon@arm.com>");