diff mbox series

[4/4] dt-bindings: PCI: microchip,pcie-host: fix missing address translation property

Message ID 20220811203306.179744-5-mail@conchuod.ie
State New
Headers show
Series Fix RISC-V/PCI dt-schema issues with dt-schema v2022.08 | expand

Commit Message

Conor Dooley Aug. 11, 2022, 8:33 p.m. UTC 
From: Conor Dooley <conor.dooley@microchip.com>

When the PCI controller node was added to the PolarFire SoC dtsi,
dt-schema was not able to detect the presence of some undocumented
properties due to how it handled unevaluatedProperties. v2022.08
introduces better validation, producing the following error:

arch/riscv/boot/dts/microchip/mpfs-polarberry.dtb: pcie@2000000000: Unevaluated properties are not allowed ('clock-names', 'microchip,axi-m-atr0' were unexpected)
        From schema: Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml

Fixes: 528a5b1f2556 ("riscv: dts: microchip: add new peripherals to icicle kit device tree")
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
---
I feel like there's a pretty good chance that this is not the way this
should have been done and the property should be marked as deprecated
but I don't know enough about PCI to answer that.
---
 .../devicetree/bindings/pci/microchip,pcie-host.yaml  | 11 +++++++++++
 1 file changed, 11 insertions(+)

Comments

Krzysztof Kozlowski Aug. 12, 2022, 7:52 a.m. UTC | #1 
On 11/08/2022 23:33, Conor Dooley wrote:
> From: Conor Dooley <conor.dooley@microchip.com>
> 
> When the PCI controller node was added to the PolarFire SoC dtsi,
> dt-schema was not able to detect the presence of some undocumented
> properties due to how it handled unevaluatedProperties. v2022.08
> introduces better validation, producing the following error:
> 
> arch/riscv/boot/dts/microchip/mpfs-polarberry.dtb: pcie@2000000000: Unevaluated properties are not allowed ('clock-names', 'microchip,axi-m-atr0' were unexpected)
>         From schema: Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml
> 
> Fixes: 528a5b1f2556 ("riscv: dts: microchip: add new peripherals to icicle kit device tree")
> Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
> ---
> I feel like there's a pretty good chance that this is not the way this
> should have been done and the property should be marked as deprecated
> but I don't know enough about PCI to answer that.

It seems bindings were added incomplete and now based on DTS (which did
not match bindings), we keep adding "missing" properties. I don't think
it is good. It creates a precedence where someone might intentionally
sneak limited bindings (without controversial property) and later claim
"I forgot to include foo,bar".

Therefore the property should pass review just like it is newly added
property.

> ---
>  .../devicetree/bindings/pci/microchip,pcie-host.yaml  | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml b/Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml
> index 9b123bcd034c..9ac34b33c4b2 100644
> --- a/Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml
> +++ b/Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml
> @@ -71,6 +71,17 @@ properties:
>    msi-parent:
>      description: MSI controller the device is capable of using.
>  
> +  microchip,axi-m-atr0:

Name is not helping. If it is offset, add such suffix (see
brcm,iproc-pcie.yaml).

Unfortunately I don't know PCIe good enough to judge whether the
property makes any sense or some other ranges-style should be used.

> +    description: |
> +      Depending on the FPGA bitstream, the AXIM address translation table in the
> +      PCIe controllers bridge layer may need to be configured. Use this property
> +      to set the address offset. For more information, see Section 1.3.3,
> +      "PCIe/AXI4 Address Translation" of the PolarFire SoC PCIe User Guide:
> +      https://www.microsemi.com/document-portal/doc_download/1245812-polarfire-fpga-and-polarfire-soc-fpga-pci-express-user-guide
> +    $ref: /schemas/types.yaml#/definitions/uint32-matrix
> +    minItems: 2

minItems should not be needed, but you should instead describe the items
in the matrix.

> +    maxItems: 2


Best regards,
Krzysztof
Conor Dooley Aug. 12, 2022, 8:20 a.m. UTC | #2 
On 12/08/2022 08:52, Krzysztof Kozlowski wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> 
> On 11/08/2022 23:33, Conor Dooley wrote:
>> From: Conor Dooley <conor.dooley@microchip.com>
>>
>> When the PCI controller node was added to the PolarFire SoC dtsi,
>> dt-schema was not able to detect the presence of some undocumented
>> properties due to how it handled unevaluatedProperties. v2022.08
>> introduces better validation, producing the following error:
>>
>> arch/riscv/boot/dts/microchip/mpfs-polarberry.dtb: pcie@2000000000: Unevaluated properties are not allowed ('clock-names', 'microchip,axi-m-atr0' were unexpected)
>>          From schema: Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml
>>
>> Fixes: 528a5b1f2556 ("riscv: dts: microchip: add new peripherals to icicle kit device tree")
>> Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
>> ---
>> I feel like there's a pretty good chance that this is not the way this
>> should have been done and the property should be marked as deprecated
>> but I don't know enough about PCI to answer that.
> 
> It seems bindings were added incomplete and now based on DTS (which did
> not match bindings), we keep adding "missing" properties. I don't think
> it is good. It creates a precedence where someone might intentionally
> sneak limited bindings (without controversial property) and later claim
> "I forgot to include foo,bar".

Yup, again pretty much the same thoughts as me. I don't think that, even
if the property is valid, should be either named as it is or only work
for translation table 0.

> 
> Therefore the property should pass review just like it is newly added
> property.

SGTM.

> 
>> ---
>>   .../devicetree/bindings/pci/microchip,pcie-host.yaml  | 11 +++++++++++
>>   1 file changed, 11 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml b/Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml
>> index 9b123bcd034c..9ac34b33c4b2 100644
>> --- a/Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml
>> +++ b/Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml
>> @@ -71,6 +71,17 @@ properties:
>>     msi-parent:
>>       description: MSI controller the device is capable of using.
>>
>> +  microchip,axi-m-atr0:
> 
> Name is not helping. If it is offset, add such suffix (see
> brcm,iproc-pcie.yaml).
> 
> Unfortunately I don't know PCIe good enough to judge whether the
> property makes any sense or some other ranges-style should be used.

Yup, I think it is similar to that. Except we have 4 tables rather
than one.

> 
>> +    description: |
>> +      Depending on the FPGA bitstream, the AXIM address translation table in the
>> +      PCIe controllers bridge layer may need to be configured. Use this property
>> +      to set the address offset. For more information, see Section 1.3.3,
>> +      "PCIe/AXI4 Address Translation" of the PolarFire SoC PCIe User Guide:
>> +      https://www.microsemi.com/document-portal/doc_download/1245812-polarfire-fpga-and-polarfire-soc-fpga-pci-express-user-guide
>> +    $ref: /schemas/types.yaml#/definitions/uint32-matrix
>> +    minItems: 2
> 
> minItems should not be needed, but you should instead describe the items
> in the matrix.

SGTM. Thanks Krzysztof.

> 
>> +    maxItems: 2
> 
> 
> Best regards,
> Krzysztof
Rob Herring Aug. 16, 2022, 5:16 p.m. UTC | #3 
On Fri, Aug 12, 2022 at 08:20:45AM +0000, Conor.Dooley@microchip.com wrote:
> On 12/08/2022 08:52, Krzysztof Kozlowski wrote:
> > EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
> > 
> > On 11/08/2022 23:33, Conor Dooley wrote:
> >> From: Conor Dooley <conor.dooley@microchip.com>
> >>
> >> When the PCI controller node was added to the PolarFire SoC dtsi,
> >> dt-schema was not able to detect the presence of some undocumented
> >> properties due to how it handled unevaluatedProperties. v2022.08
> >> introduces better validation, producing the following error:
> >>
> >> arch/riscv/boot/dts/microchip/mpfs-polarberry.dtb: pcie@2000000000: Unevaluated properties are not allowed ('clock-names', 'microchip,axi-m-atr0' were unexpected)
> >>          From schema: Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml
> >>
> >> Fixes: 528a5b1f2556 ("riscv: dts: microchip: add new peripherals to icicle kit device tree")
> >> Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
> >> ---
> >> I feel like there's a pretty good chance that this is not the way this
> >> should have been done and the property should be marked as deprecated
> >> but I don't know enough about PCI to answer that.
> > 
> > It seems bindings were added incomplete and now based on DTS (which did
> > not match bindings), we keep adding "missing" properties. I don't think
> > it is good. It creates a precedence where someone might intentionally
> > sneak limited bindings (without controversial property) and later claim
> > "I forgot to include foo,bar".
> 
> Yup, again pretty much the same thoughts as me. I don't think that, even
> if the property is valid, should be either named as it is or only work
> for translation table 0.
> 
> > 
> > Therefore the property should pass review just like it is newly added
> > property.
> 
> SGTM.
> 
> > 
> >> ---
> >>   .../devicetree/bindings/pci/microchip,pcie-host.yaml  | 11 +++++++++++
> >>   1 file changed, 11 insertions(+)
> >>
> >> diff --git a/Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml b/Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml
> >> index 9b123bcd034c..9ac34b33c4b2 100644
> >> --- a/Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml
> >> +++ b/Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml
> >> @@ -71,6 +71,17 @@ properties:
> >>     msi-parent:
> >>       description: MSI controller the device is capable of using.
> >>
> >> +  microchip,axi-m-atr0:
> > 
> > Name is not helping. If it is offset, add such suffix (see
> > brcm,iproc-pcie.yaml).
> > 
> > Unfortunately I don't know PCIe good enough to judge whether the
> > property makes any sense or some other ranges-style should be used.
> 
> Yup, I think it is similar to that. Except we have 4 tables rather
> than one.

Looks to me like dma-ranges is the answer.

Rob
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml b/Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml
index 9b123bcd034c..9ac34b33c4b2 100644
--- a/Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml
+++ b/Documentation/devicetree/bindings/pci/microchip,pcie-host.yaml
@@ -71,6 +71,17 @@  properties:
   msi-parent:
     description: MSI controller the device is capable of using.
 
+  microchip,axi-m-atr0:
+    description: |
+      Depending on the FPGA bitstream, the AXIM address translation table in the
+      PCIe controllers bridge layer may need to be configured. Use this property
+      to set the address offset. For more information, see Section 1.3.3,
+      "PCIe/AXI4 Address Translation" of the PolarFire SoC PCIe User Guide:
+      https://www.microsemi.com/document-portal/doc_download/1245812-polarfire-fpga-and-polarfire-soc-fpga-pci-express-user-guide
+    $ref: /schemas/types.yaml#/definitions/uint32-matrix
+    minItems: 2
+    maxItems: 2
+
   legacy-interrupt-controller:
     type: object
     properties: