| Message ID | 20231219-topic-8280_smmuv3-v2-2-c67bd3226687@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Describe SC8280XP PCIe SMMU | expand |
On Sat, Mar 09, 2024 at 02:31:10PM +0100, Konrad Dybcio wrote: > SC8280XP actually has a third SMMU, which can be seen in e.g. the IORT > ACPI table and is used for the PCIe hosts. > > Unfortunately though, the secure firmware seems to be configured in a > way such that Linux can't touch it, not even read back the ID registers. > It also seems like the SMMU is configured to run in some sort of bypass > mode, completely opaque to the OS. > > Describe it so that one can configure it when running Linux as a > hypervisor (e.g with [1]) and for hardware description completeness. > > [1] https://github.com/TravMurav/slbounce > Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org> Have this information been validated? Or are you suggesting we add it for documentation purposes? Regards, Bjorn > --- > arch/arm64/boot/dts/qcom/sc8280xp.dtsi | 16 ++++++++++++++++ > 1 file changed, 16 insertions(+) > > diff --git a/arch/arm64/boot/dts/qcom/sc8280xp.dtsi b/arch/arm64/boot/dts/qcom/sc8280xp.dtsi > index a5b194813079..28edd30a9c04 100644 > --- a/arch/arm64/boot/dts/qcom/sc8280xp.dtsi > +++ b/arch/arm64/boot/dts/qcom/sc8280xp.dtsi > @@ -4648,6 +4648,22 @@ cci3_i2c1_sleep: cci3-i2c1-sleep-pins { > }; > }; > > + pcie_smmu: iommu@14f80000 { > + compatible = "qcom,sc8280xp-smmu-v3", "arm,smmu-v3"; > + reg = <0 0x14f80000 0 0x80000>; > + interrupts = <GIC_SPI 951 IRQ_TYPE_EDGE_RISING>, > + <GIC_SPI 955 IRQ_TYPE_EDGE_RISING>, > + <GIC_SPI 953 IRQ_TYPE_EDGE_RISING>; > + interrupt-names = "eventq", > + "gerror", > + "cmdq-sync"; > + #iommu-cells = <1>; > + dma-coherent; > + > + /* The hypervisor prevents register access from Linux */ > + status = "reserved"; > + }; > + > apps_smmu: iommu@15000000 { > compatible = "qcom,sc8280xp-smmu-500", "arm,mmu-500"; > reg = <0 0x15000000 0 0x100000>; > > -- > 2.44.0 >
On 18.03.2024 02:31, Bjorn Andersson wrote: > On Sat, Mar 09, 2024 at 02:31:10PM +0100, Konrad Dybcio wrote: >> SC8280XP actually has a third SMMU, which can be seen in e.g. the IORT >> ACPI table and is used for the PCIe hosts. >> >> Unfortunately though, the secure firmware seems to be configured in a >> way such that Linux can't touch it, not even read back the ID registers. >> It also seems like the SMMU is configured to run in some sort of bypass >> mode, completely opaque to the OS. >> >> Describe it so that one can configure it when running Linux as a >> hypervisor (e.g with [1]) and for hardware description completeness. >> >> [1] https://github.com/TravMurav/slbounce >> Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org> > > Have this information been validated? Or are you suggesting we add it > for documentation purposes? I confirmed the platforms boots up with this if the hypervisor is gone. Konrad
diff --git a/arch/arm64/boot/dts/qcom/sc8280xp.dtsi b/arch/arm64/boot/dts/qcom/sc8280xp.dtsi index a5b194813079..28edd30a9c04 100644 --- a/arch/arm64/boot/dts/qcom/sc8280xp.dtsi +++ b/arch/arm64/boot/dts/qcom/sc8280xp.dtsi @@ -4648,6 +4648,22 @@ cci3_i2c1_sleep: cci3-i2c1-sleep-pins { }; }; + pcie_smmu: iommu@14f80000 { + compatible = "qcom,sc8280xp-smmu-v3", "arm,smmu-v3"; + reg = <0 0x14f80000 0 0x80000>; + interrupts = <GIC_SPI 951 IRQ_TYPE_EDGE_RISING>, + <GIC_SPI 955 IRQ_TYPE_EDGE_RISING>, + <GIC_SPI 953 IRQ_TYPE_EDGE_RISING>; + interrupt-names = "eventq", + "gerror", + "cmdq-sync"; + #iommu-cells = <1>; + dma-coherent; + + /* The hypervisor prevents register access from Linux */ + status = "reserved"; + }; + apps_smmu: iommu@15000000 { compatible = "qcom,sc8280xp-smmu-500", "arm,mmu-500"; reg = <0 0x15000000 0 0x100000>;
SC8280XP actually has a third SMMU, which can be seen in e.g. the IORT ACPI table and is used for the PCIe hosts. Unfortunately though, the secure firmware seems to be configured in a way such that Linux can't touch it, not even read back the ID registers. It also seems like the SMMU is configured to run in some sort of bypass mode, completely opaque to the OS. Describe it so that one can configure it when running Linux as a hypervisor (e.g with [1]) and for hardware description completeness. [1] https://github.com/TravMurav/slbounce Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org> --- arch/arm64/boot/dts/qcom/sc8280xp.dtsi | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)