diff mbox series

[v1,2/3] arm64: dts: qcom: msm8998: Add PCIe SMMU node

Message ID 82ab78ee-4a38-4eee-f064-272b6f964f17@free.fr
State Not Applicable
Delegated to: Lorenzo Pieralisi
Headers show
Series PCIe and AR8151 on APQ8098/MSM8998 | expand

Commit Message

Marc Gonzalez March 28, 2019, 5:05 p.m. UTC
ANOC1 SMMU filters PCIe accesses.

Signed-off-by: Marc Gonzalez <marc.w.gonzalez@free.fr>
---
 arch/arm64/boot/dts/qcom/msm8998.dtsi | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

Comments

Marc Gonzalez March 29, 2019, 10:51 a.m. UTC | #1
On 28/03/2019 18:05, Marc Gonzalez wrote:

> ANOC1 SMMU filters PCIe accesses.

I'm not sure this description is entirely accurate...

ANOC likely stands for "Application Network-On-Chip"


>  arch/arm64/boot/dts/qcom/msm8998.dtsi | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/qcom/msm8998.dtsi b/arch/arm64/boot/dts/qcom/msm8998.dtsi
> index f9a922fdae75..5a1c0961b281 100644
> --- a/arch/arm64/boot/dts/qcom/msm8998.dtsi
> +++ b/arch/arm64/boot/dts/qcom/msm8998.dtsi
> @@ -606,6 +606,21 @@
>  			#thermal-sensor-cells = <1>;
>  		};
>  
> +		anoc1_smmu: arm,smmu@1680000 {
> +			compatible = "qcom,msm8996-smmu-v2", "qcom,smmu-v2";

Maybe I should instead use "qcom,msm8998-smmu-v2", "qcom,smmu-v2";
and define "qcom,msm8998-smmu-v2" in
Documentation/devicetree/bindings/iommu/arm,smmu.txt ?
(Would the Documentation change need to be in a separate patch?)

> +			reg = <0x01680000 0x10000>;
> +			#iommu-cells = <1>;

I'm not sure about this property. IIRC, Robin said <0> is not valid,
but I don't have any iommus prop, only iommu-map.

> +
> +			#global-interrupts = <0>;
> +			interrupts =
> +				<GIC_SPI 364 IRQ_TYPE_EDGE_RISING>,
> +				<GIC_SPI 365 IRQ_TYPE_EDGE_RISING>,
> +				<GIC_SPI 366 IRQ_TYPE_EDGE_RISING>,
> +				<GIC_SPI 367 IRQ_TYPE_EDGE_RISING>,
> +				<GIC_SPI 368 IRQ_TYPE_EDGE_RISING>,
> +				<GIC_SPI 369 IRQ_TYPE_EDGE_RISING>;
> +		};
> +

The rest of the node looks fairly straight-forward.

DT code was adapted from:

https://source.codeaurora.org/quic/la/kernel/msm-4.4/tree/arch/arm/boot/dts/qcom/msm-arm-smmu-8998.dtsi?h=LE.UM.1.3.r3.25#n18

I left out the so-called implementation-defined init:

https://source.codeaurora.org/quic/la/kernel/msm-4.4/tree/arch/arm/boot/dts/qcom/msm-arm-smmu-impl-defs-8998.dtsi?h=LE.UM.1.3.r3.25#n123

Should I try to merge this part in mainline?
(I don't have any documentation for it though.)

Regards.
Robin Murphy March 29, 2019, 6:29 p.m. UTC | #2
On 29/03/2019 10:51, Marc Gonzalez wrote:
> On 28/03/2019 18:05, Marc Gonzalez wrote:
> 
>> ANOC1 SMMU filters PCIe accesses.
> 
> I'm not sure this description is entirely accurate...
> 
> ANOC likely stands for "Application Network-On-Chip"
> 
> 
>>   arch/arm64/boot/dts/qcom/msm8998.dtsi | 15 +++++++++++++++
>>   1 file changed, 15 insertions(+)
>>
>> diff --git a/arch/arm64/boot/dts/qcom/msm8998.dtsi b/arch/arm64/boot/dts/qcom/msm8998.dtsi
>> index f9a922fdae75..5a1c0961b281 100644
>> --- a/arch/arm64/boot/dts/qcom/msm8998.dtsi
>> +++ b/arch/arm64/boot/dts/qcom/msm8998.dtsi
>> @@ -606,6 +606,21 @@
>>   			#thermal-sensor-cells = <1>;
>>   		};
>>   
>> +		anoc1_smmu: arm,smmu@1680000 {
>> +			compatible = "qcom,msm8996-smmu-v2", "qcom,smmu-v2";
> 
> Maybe I should instead use "qcom,msm8998-smmu-v2", "qcom,smmu-v2";
> and define "qcom,msm8998-smmu-v2" in
> Documentation/devicetree/bindings/iommu/arm,smmu.txt ?

Yes please.

> (Would the Documentation change need to be in a separate patch?)

That's generally preferred, yes.

> 
>> +			reg = <0x01680000 0x10000>;
>> +			#iommu-cells = <1>;
> 
> I'm not sure about this property. IIRC, Robin said <0> is not valid,
> but I don't have any iommus prop, only iommu-map.

You have to join the dots between the various bindings a little, but the 
iommu-base part of each iommu-map entry is an IOMMU specifier, and IOMMU 
specifiers are #iommu-cells long.

To cut a long story short, 1 is definitely appropriate, because 
arm-smmu's definition of a 2-cell specifier wouldn't make much sense in 
the iommu-map context (and the current code for parsing iommu-map 
actually just assumes 1 anyway).

>> +
>> +			#global-interrupts = <0>;
>> +			interrupts =
>> +				<GIC_SPI 364 IRQ_TYPE_EDGE_RISING>,
>> +				<GIC_SPI 365 IRQ_TYPE_EDGE_RISING>,
>> +				<GIC_SPI 366 IRQ_TYPE_EDGE_RISING>,
>> +				<GIC_SPI 367 IRQ_TYPE_EDGE_RISING>,
>> +				<GIC_SPI 368 IRQ_TYPE_EDGE_RISING>,
>> +				<GIC_SPI 369 IRQ_TYPE_EDGE_RISING>;
>> +		};
>> +
> 
> The rest of the node looks fairly straight-forward.

You should probably have some "bus" and "iface" clocks too, per the 
requirement of "qcom,smmu-v2". Maybe Vivek might know what's relevant 
for MSM8998?

> 
> DT code was adapted from:
> 
> https://source.codeaurora.org/quic/la/kernel/msm-4.4/tree/arch/arm/boot/dts/qcom/msm-arm-smmu-8998.dtsi?h=LE.UM.1.3.r3.25#n18
> 
> I left out the so-called implementation-defined init:
> 
> https://source.codeaurora.org/quic/la/kernel/msm-4.4/tree/arch/arm/boot/dts/qcom/msm-arm-smmu-impl-defs-8998.dtsi?h=LE.UM.1.3.r3.25#n123
> 
> Should I try to merge this part in mainline?
> (I don't have any documentation for it though.)

"pls no :("

I'm not sure what route the path takes from "DT describes the platform" 
to get to "DT lists opaque register addresses and magic data to write 
into them", but I imagine it might involve getting hit in the head along 
the way.

Robin.
Jeffrey Hugo March 29, 2019, 7:42 p.m. UTC | #3
On 3/29/2019 12:29 PM, Robin Murphy wrote:
> On 29/03/2019 10:51, Marc Gonzalez wrote:
>> On 28/03/2019 18:05, Marc Gonzalez wrote:
>>> +
>>> +            #global-interrupts = <0>;
>>> +            interrupts =
>>> +                <GIC_SPI 364 IRQ_TYPE_EDGE_RISING>,
>>> +                <GIC_SPI 365 IRQ_TYPE_EDGE_RISING>,
>>> +                <GIC_SPI 366 IRQ_TYPE_EDGE_RISING>,
>>> +                <GIC_SPI 367 IRQ_TYPE_EDGE_RISING>,
>>> +                <GIC_SPI 368 IRQ_TYPE_EDGE_RISING>,
>>> +                <GIC_SPI 369 IRQ_TYPE_EDGE_RISING>;
>>> +        };
>>> +
>>
>> The rest of the node looks fairly straight-forward.
> 
> You should probably have some "bus" and "iface" clocks too, per the 
> requirement of "qcom,smmu-v2". Maybe Vivek might know what's relevant 
> for MSM8998?
> 

The clocks that power the SMMU are not under the control of Linux, but 
rather the RPM subsystem.  The interface to them is the interconnect 
framework, which does not yet support 8998 per my understanding.  The 
clocks will always be on, but perhaps not at the best rate for 
performance until the interconnect is brought in.
Vivek Gautam March 30, 2019, 2:18 p.m. UTC | #4
Hi Marc,

On Fri, Mar 29, 2019 at 11:59 PM Robin Murphy <robin.murphy@arm.com> wrote:
>
> On 29/03/2019 10:51, Marc Gonzalez wrote:
> > On 28/03/2019 18:05, Marc Gonzalez wrote:
> >
> >> ANOC1 SMMU filters PCIe accesses.
> >
> > I'm not sure this description is entirely accurate...
> >
> > ANOC likely stands for "Application Network-On-Chip"

How about simply saying - "Add device node for ANOC1 SMMU" for
commit title.
Commit text -
ANOC1 smmu services a list of peripherals - USB, UFS, BLSP2, and PCIe.
Add the device node for this smmu.

> >
> >
> >>   arch/arm64/boot/dts/qcom/msm8998.dtsi | 15 +++++++++++++++
> >>   1 file changed, 15 insertions(+)
> >>
> >> diff --git a/arch/arm64/boot/dts/qcom/msm8998.dtsi b/arch/arm64/boot/dts/qcom/msm8998.dtsi
> >> index f9a922fdae75..5a1c0961b281 100644
> >> --- a/arch/arm64/boot/dts/qcom/msm8998.dtsi
> >> +++ b/arch/arm64/boot/dts/qcom/msm8998.dtsi
> >> @@ -606,6 +606,21 @@
> >>                      #thermal-sensor-cells = <1>;
> >>              };
> >>
> >> +            anoc1_smmu: arm,smmu@1680000 {
> >> +                    compatible = "qcom,msm8996-smmu-v2", "qcom,smmu-v2";
> >
> > Maybe I should instead use "qcom,msm8998-smmu-v2", "qcom,smmu-v2";
> > and define "qcom,msm8998-smmu-v2" in
> > Documentation/devicetree/bindings/iommu/arm,smmu.txt ?
>
> Yes please.
>
> > (Would the Documentation change need to be in a separate patch?)
>
> That's generally preferred, yes.
>
> >
> >> +                    reg = <0x01680000 0x10000>;
> >> +                    #iommu-cells = <1>;
> >
> > I'm not sure about this property. IIRC, Robin said <0> is not valid,
> > but I don't have any iommus prop, only iommu-map.
>
> You have to join the dots between the various bindings a little, but the
> iommu-base part of each iommu-map entry is an IOMMU specifier, and IOMMU
> specifiers are #iommu-cells long.
>
> To cut a long story short, 1 is definitely appropriate, because
> arm-smmu's definition of a 2-cell specifier wouldn't make much sense in
> the iommu-map context (and the current code for parsing iommu-map
> actually just assumes 1 anyway).

Besides this,
Looking at the SID mappings for ANOC1 smmu, devices such as USB, and UFS
can very well enable iommu support, and thus iommu-cells = 1 seems
like the correct thingy.

>
> >> +
> >> +                    #global-interrupts = <0>;
> >> +                    interrupts =
> >> +                            <GIC_SPI 364 IRQ_TYPE_EDGE_RISING>,
> >> +                            <GIC_SPI 365 IRQ_TYPE_EDGE_RISING>,
> >> +                            <GIC_SPI 366 IRQ_TYPE_EDGE_RISING>,
> >> +                            <GIC_SPI 367 IRQ_TYPE_EDGE_RISING>,
> >> +                            <GIC_SPI 368 IRQ_TYPE_EDGE_RISING>,
> >> +                            <GIC_SPI 369 IRQ_TYPE_EDGE_RISING>;
> >> +            };
> >> +
> >
> > The rest of the node looks fairly straight-forward.
>
> You should probably have some "bus" and "iface" clocks too, per the
> requirement of "qcom,smmu-v2". Maybe Vivek might know what's relevant
> for MSM8998?

As Jeffrey rightly mentioned, these clocks are not under the control of Linux.
So, we won't need to add clocks to this SMMU.

Thanks
Vivek

>
> >
> > DT code was adapted from:
> >
> > https://source.codeaurora.org/quic/la/kernel/msm-4.4/tree/arch/arm/boot/dts/qcom/msm-arm-smmu-8998.dtsi?h=LE.UM.1.3.r3.25#n18
> >
> > I left out the so-called implementation-defined init:
> >
> > https://source.codeaurora.org/quic/la/kernel/msm-4.4/tree/arch/arm/boot/dts/qcom/msm-arm-smmu-impl-defs-8998.dtsi?h=LE.UM.1.3.r3.25#n123
> >
> > Should I try to merge this part in mainline?
> > (I don't have any documentation for it though.)
>
> "pls no :("
>
> I'm not sure what route the path takes from "DT describes the platform"
> to get to "DT lists opaque register addresses and magic data to write
> into them", but I imagine it might involve getting hit in the head along
> the way.
>
> Robin.
> _______________________________________________
> iommu mailing list
> iommu@lists.linux-foundation.org
> https://lists.linuxfoundation.org/mailman/listinfo/iommu
Robin Murphy April 2, 2019, 1:54 p.m. UTC | #5
On 30/03/2019 14:18, Vivek Gautam wrote:
>> You should probably have some "bus" and "iface" clocks too, per the
>> requirement of "qcom,smmu-v2". Maybe Vivek might know what's relevant
>> for MSM8998?
> 
> As Jeffrey rightly mentioned, these clocks are not under the control of Linux.
> So, we won't need to add clocks to this SMMU.

OK, in that case the "clock-names" part of binding doc probably wants 
refining to reflect which implementations do actually require clocks.

Robin.
Vivek Gautam April 3, 2019, 9:26 a.m. UTC | #6
On 4/2/2019 7:24 PM, Robin Murphy wrote:
> On 30/03/2019 14:18, Vivek Gautam wrote:
>>> You should probably have some "bus" and "iface" clocks too, per the
>>> requirement of "qcom,smmu-v2". Maybe Vivek might know what's relevant
>>> for MSM8998?
>>
>> As Jeffrey rightly mentioned, these clocks are not under the control 
>> of Linux.
>> So, we won't need to add clocks to this SMMU.
>
> OK, in that case the "clock-names" part of binding doc probably wants 
> refining to reflect which implementations do actually require clocks.

Certainly.
Marc, do you want to push a patch for the same? Or, let me know I can 
prepare one.

Thanks
Vivek

>
> Robin.
diff mbox series

Patch

diff --git a/arch/arm64/boot/dts/qcom/msm8998.dtsi b/arch/arm64/boot/dts/qcom/msm8998.dtsi
index f9a922fdae75..5a1c0961b281 100644
--- a/arch/arm64/boot/dts/qcom/msm8998.dtsi
+++ b/arch/arm64/boot/dts/qcom/msm8998.dtsi
@@ -606,6 +606,21 @@ 
 			#thermal-sensor-cells = <1>;
 		};
 
+		anoc1_smmu: arm,smmu@1680000 {
+			compatible = "qcom,msm8996-smmu-v2", "qcom,smmu-v2";
+			reg = <0x01680000 0x10000>;
+			#iommu-cells = <1>;
+
+			#global-interrupts = <0>;
+			interrupts =
+				<GIC_SPI 364 IRQ_TYPE_EDGE_RISING>,
+				<GIC_SPI 365 IRQ_TYPE_EDGE_RISING>,
+				<GIC_SPI 366 IRQ_TYPE_EDGE_RISING>,
+				<GIC_SPI 367 IRQ_TYPE_EDGE_RISING>,
+				<GIC_SPI 368 IRQ_TYPE_EDGE_RISING>,
+				<GIC_SPI 369 IRQ_TYPE_EDGE_RISING>;
+		};
+
 		tcsr_mutex_regs: syscon@1f40000 {
 			compatible = "syscon";
 			reg = <0x1f40000 0x20000>;