diff mbox series

[1/4] dt-bindings: remoteproc: qcom: wcnss: Add WCN3680B compatible

Message ID 20231015-fp3-wcnss-v1-1-1b311335e931@z3ntu.xyz
State New
Headers show
Series [1/4] dt-bindings: remoteproc: qcom: wcnss: Add WCN3680B compatible | expand

Commit Message

Luca Weiss Oct. 15, 2023, 8:03 p.m. UTC
Add a compatible for the iris subnode in the WCNSS PIL.

Signed-off-by: Luca Weiss <luca@z3ntu.xyz>
---
 Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml | 1 +
 1 file changed, 1 insertion(+)

Comments

Loic Poulain Oct. 16, 2023, 1:16 p.m. UTC | #1
On Mon, 16 Oct 2023 at 07:35, Krzysztof Kozlowski
<krzysztof.kozlowski@linaro.org> wrote:
>
> On 15/10/2023 22:03, Luca Weiss wrote:
> > Add a compatible for the iris subnode in the WCNSS PIL.
> >
> > Signed-off-by: Luca Weiss <luca@z3ntu.xyz>
> > ---
> >  Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml | 1 +
> >  1 file changed, 1 insertion(+)
> >
> > diff --git a/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml b/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml
> > index 45eb42bd3c2c..0e5e0b7a0610 100644
> > --- a/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml
> > +++ b/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml
> > @@ -111,6 +111,7 @@ properties:
> >            - qcom,wcn3660
> >            - qcom,wcn3660b
> >            - qcom,wcn3680
> > +          - qcom,wcn3680b
>
> Looks like this should be made as compatible with qcom,wcn3680 (so with
> fallback).

Yes, agree, let's do a regular fallback as there is nothing 'b'
specific in the driver:
`compatible = "qcom,wcn3680b", "qcom,wcn3680";`

And yes, we should also have done that for qcom,wcn3660b...

Regards,
Loic
Stephan Gerhold Oct. 16, 2023, 2:44 p.m. UTC | #2
On Mon, Oct 16, 2023 at 03:16:14PM +0200, Loic Poulain wrote:
> On Mon, 16 Oct 2023 at 07:35, Krzysztof Kozlowski
> <krzysztof.kozlowski@linaro.org> wrote:
> >
> > On 15/10/2023 22:03, Luca Weiss wrote:
> > > Add a compatible for the iris subnode in the WCNSS PIL.
> > >
> > > Signed-off-by: Luca Weiss <luca@z3ntu.xyz>
> > > ---
> > >  Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml | 1 +
> > >  1 file changed, 1 insertion(+)
> > >
> > > diff --git a/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml b/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml
> > > index 45eb42bd3c2c..0e5e0b7a0610 100644
> > > --- a/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml
> > > +++ b/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml
> > > @@ -111,6 +111,7 @@ properties:
> > >            - qcom,wcn3660
> > >            - qcom,wcn3660b
> > >            - qcom,wcn3680
> > > +          - qcom,wcn3680b
> >
> > Looks like this should be made as compatible with qcom,wcn3680 (so with
> > fallback).
> 
> Yes, agree, let's do a regular fallback as there is nothing 'b'
> specific in the driver:
> `compatible = "qcom,wcn3680b", "qcom,wcn3680";`
> 
> And yes, we should also have done that for qcom,wcn3660b...
> 

I don't think this would have worked properly for qcom,wcn3660b:

 - It's not compatible with "qcom,wcn3660", because they have different
   regulator voltage requirements. wcn3660(a?) needs vddpa with
   2.9-3.0V, but wcn3660b needs 3.3V. That's why wcn3660b uses the
   wcn3680_data in qcom_wcnss.iris.c. Otherwise if you would run an
   older kernel that knows "qcom,wcn3660" but not "qcom,wcn3660b" it
   would apply the wrong voltage.

 - It's not compatible with "qcom,wcn3680" either because that is used
   as indication if 802.11ac is supported (wcn3660b doesn't).

The main question here is: What does the current "qcom,wcn3680"
compatible actually represent? It's defined with vddpa = 3.3V in the
driver, which would suggest that:

 1. It's actually meant to represent WCN3680B, which needs 3.3V vddpa
    like WCN3660B, or

 2. WCN3680(A?) has different requirements than WCN3660(A?) and also
    needs 3.3V vddpa. But then what is the difference between
    WCN3680(A?) and WCN3680B? Is there even a variant without ...B?

There is public documentation for WCN3660B and WCN3680B but the non-B
variants are shrouded in mystery.

Thanks,
Stephan
Luca Weiss Nov. 25, 2023, 12:25 p.m. UTC | #3
On Montag, 16. Oktober 2023 16:44:28 CET Stephan Gerhold wrote:
> On Mon, Oct 16, 2023 at 03:16:14PM +0200, Loic Poulain wrote:
> > On Mon, 16 Oct 2023 at 07:35, Krzysztof Kozlowski
> > 
> > <krzysztof.kozlowski@linaro.org> wrote:
> > > On 15/10/2023 22:03, Luca Weiss wrote:
> > > > Add a compatible for the iris subnode in the WCNSS PIL.
> > > > 
> > > > Signed-off-by: Luca Weiss <luca@z3ntu.xyz>
> > > > ---
> > > > 
> > > >  Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml | 1
> > > >  +
> > > >  1 file changed, 1 insertion(+)
> > > > 
> > > > diff --git
> > > > a/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml
> > > > b/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml
> > > > index 45eb42bd3c2c..0e5e0b7a0610 100644
> > > > --- a/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml
> > > > +++ b/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml
> > > > 
> > > > @@ -111,6 +111,7 @@ properties:
> > > >            - qcom,wcn3660
> > > >            - qcom,wcn3660b
> > > >            - qcom,wcn3680
> > > > 
> > > > +          - qcom,wcn3680b
> > > 
> > > Looks like this should be made as compatible with qcom,wcn3680 (so with
> > > fallback).
> > 
> > Yes, agree, let's do a regular fallback as there is nothing 'b'
> > specific in the driver:
> > `compatible = "qcom,wcn3680b", "qcom,wcn3680";`
> > 
> > And yes, we should also have done that for qcom,wcn3660b...
> 
> I don't think this would have worked properly for qcom,wcn3660b:
> 
>  - It's not compatible with "qcom,wcn3660", because they have different
>    regulator voltage requirements. wcn3660(a?) needs vddpa with
>    2.9-3.0V, but wcn3660b needs 3.3V. That's why wcn3660b uses the
>    wcn3680_data in qcom_wcnss.iris.c. Otherwise if you would run an
>    older kernel that knows "qcom,wcn3660" but not "qcom,wcn3660b" it
>    would apply the wrong voltage.
> 
>  - It's not compatible with "qcom,wcn3680" either because that is used
>    as indication if 802.11ac is supported (wcn3660b doesn't).
> 
> The main question here is: What does the current "qcom,wcn3680"
> compatible actually represent? It's defined with vddpa = 3.3V in the
> driver, which would suggest that:
> 
>  1. It's actually meant to represent WCN3680B, which needs 3.3V vddpa
>     like WCN3660B, or
> 
>  2. WCN3680(A?) has different requirements than WCN3660(A?) and also
>     needs 3.3V vddpa. But then what is the difference between
>     WCN3680(A?) and WCN3680B? Is there even a variant without ...B?
> 
> There is public documentation for WCN3660B and WCN3680B but the non-B
> variants are shrouded in mystery.

Hi Stephan (and everyone),

Do you have a suggestion how to move this patchset forward? Is the fallback 
compatible that was suggested okay for the wcn3680b situation?

  compatible = "qcom,wcn3680b", "qcom,wcn3680";

If so, I'll make v2 with that implemented.

Regards
Luca

> 
> Thanks,
> Stephan
Stephan Gerhold Nov. 27, 2023, 8:07 p.m. UTC | #4
On Sat, Nov 25, 2023 at 01:25:22PM +0100, Luca Weiss wrote:
> On Montag, 16. Oktober 2023 16:44:28 CET Stephan Gerhold wrote:
> > On Mon, Oct 16, 2023 at 03:16:14PM +0200, Loic Poulain wrote:
> > > On Mon, 16 Oct 2023 at 07:35, Krzysztof Kozlowski
> > > 
> > > <krzysztof.kozlowski@linaro.org> wrote:
> > > > On 15/10/2023 22:03, Luca Weiss wrote:
> > > > > Add a compatible for the iris subnode in the WCNSS PIL.
> > > > > 
> > > > > Signed-off-by: Luca Weiss <luca@z3ntu.xyz>
> > > > > ---
> > > > > 
> > > > >  Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml | 1
> > > > >  +
> > > > >  1 file changed, 1 insertion(+)
> > > > > 
> > > > > diff --git
> > > > > a/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml
> > > > > b/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml
> > > > > index 45eb42bd3c2c..0e5e0b7a0610 100644
> > > > > --- a/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml
> > > > > +++ b/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml
> > > > > 
> > > > > @@ -111,6 +111,7 @@ properties:
> > > > >            - qcom,wcn3660
> > > > >            - qcom,wcn3660b
> > > > >            - qcom,wcn3680
> > > > > 
> > > > > +          - qcom,wcn3680b
> > > > 
> > > > Looks like this should be made as compatible with qcom,wcn3680 (so with
> > > > fallback).
> > > 
> > > Yes, agree, let's do a regular fallback as there is nothing 'b'
> > > specific in the driver:
> > > `compatible = "qcom,wcn3680b", "qcom,wcn3680";`
> > > 
> > > And yes, we should also have done that for qcom,wcn3660b...
> > 
> > I don't think this would have worked properly for qcom,wcn3660b:
> > 
> >  - It's not compatible with "qcom,wcn3660", because they have different
> >    regulator voltage requirements. wcn3660(a?) needs vddpa with
> >    2.9-3.0V, but wcn3660b needs 3.3V. That's why wcn3660b uses the
> >    wcn3680_data in qcom_wcnss.iris.c. Otherwise if you would run an
> >    older kernel that knows "qcom,wcn3660" but not "qcom,wcn3660b" it
> >    would apply the wrong voltage.
> > 
> >  - It's not compatible with "qcom,wcn3680" either because that is used
> >    as indication if 802.11ac is supported (wcn3660b doesn't).
> > 
> > The main question here is: What does the current "qcom,wcn3680"
> > compatible actually represent? It's defined with vddpa = 3.3V in the
> > driver, which would suggest that:
> > 
> >  1. It's actually meant to represent WCN3680B, which needs 3.3V vddpa
> >     like WCN3660B, or
> > 
> >  2. WCN3680(A?) has different requirements than WCN3660(A?) and also
> >     needs 3.3V vddpa. But then what is the difference between
> >     WCN3680(A?) and WCN3680B? Is there even a variant without ...B?
> > 
> > There is public documentation for WCN3660B and WCN3680B but the non-B
> > variants are shrouded in mystery.
> 
> Hi Stephan (and everyone),
> 
> Do you have a suggestion how to move this patchset forward? Is the fallback 
> compatible that was suggested okay for the wcn3680b situation?
> 
>   compatible = "qcom,wcn3680b", "qcom,wcn3680";
> 
> If so, I'll make v2 with that implemented.
> 

Personally, I would just go with what exists already and use the
existing "qcom,wcn3680" compatible as-is. No one has provided evidence
that there is actually something like a WCN3680(A), without a 'B' at the
end. Also, all existing users of the "qcom,wcn3680" compatible upstream
actually seem to refer to WCN3680B (I'm quite sure apq8039-t2 has
WCN3680B, MSM8974 isn't entirely clear but iirc you mentioned there was
some schematic of a MSM8974 device which says WCN3680B as well).

It would be nice to have the compatible perfectly correct and complete,
but I see no point to extend it with additional information that we
can't properly verify.

Or do you actually need a different compatible to customize something in
the driver?

Thanks,
Stephan
Luca Weiss Nov. 27, 2023, 8:27 p.m. UTC | #5
On Montag, 27. November 2023 21:07:28 CET Stephan Gerhold wrote:
> On Sat, Nov 25, 2023 at 01:25:22PM +0100, Luca Weiss wrote:
> > On Montag, 16. Oktober 2023 16:44:28 CET Stephan Gerhold wrote:
> > > On Mon, Oct 16, 2023 at 03:16:14PM +0200, Loic Poulain wrote:
> > > > On Mon, 16 Oct 2023 at 07:35, Krzysztof Kozlowski
> > > > 
> > > > <krzysztof.kozlowski@linaro.org> wrote:
> > > > > On 15/10/2023 22:03, Luca Weiss wrote:
> > > > > > Add a compatible for the iris subnode in the WCNSS PIL.
> > > > > > 
> > > > > > Signed-off-by: Luca Weiss <luca@z3ntu.xyz>
> > > > > > ---
> > > > > > 
> > > > > >  Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml
> > > > > >  | 1
> > > > > >  +
> > > > > >  1 file changed, 1 insertion(+)
> > > > > > 
> > > > > > diff --git
> > > > > > a/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml
> > > > > > b/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml
> > > > > > index 45eb42bd3c2c..0e5e0b7a0610 100644
> > > > > > ---
> > > > > > a/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yam
> > > > > > l
> > > > > > +++
> > > > > > b/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yam
> > > > > > l
> > > > > > 
> > > > > > @@ -111,6 +111,7 @@ properties:
> > > > > >            - qcom,wcn3660
> > > > > >            - qcom,wcn3660b
> > > > > >            - qcom,wcn3680
> > > > > > 
> > > > > > +          - qcom,wcn3680b
> > > > > 
> > > > > Looks like this should be made as compatible with qcom,wcn3680 (so
> > > > > with
> > > > > fallback).
> > > > 
> > > > Yes, agree, let's do a regular fallback as there is nothing 'b'
> > > > specific in the driver:
> > > > `compatible = "qcom,wcn3680b", "qcom,wcn3680";`
> > > > 
> > > > And yes, we should also have done that for qcom,wcn3660b...
> > > 
> > > I don't think this would have worked properly for qcom,wcn3660b:
> > >  - It's not compatible with "qcom,wcn3660", because they have different
> > >  
> > >    regulator voltage requirements. wcn3660(a?) needs vddpa with
> > >    2.9-3.0V, but wcn3660b needs 3.3V. That's why wcn3660b uses the
> > >    wcn3680_data in qcom_wcnss.iris.c. Otherwise if you would run an
> > >    older kernel that knows "qcom,wcn3660" but not "qcom,wcn3660b" it
> > >    would apply the wrong voltage.
> > >  
> > >  - It's not compatible with "qcom,wcn3680" either because that is used
> > >  
> > >    as indication if 802.11ac is supported (wcn3660b doesn't).
> > > 
> > > The main question here is: What does the current "qcom,wcn3680"
> > > compatible actually represent? It's defined with vddpa = 3.3V in the
> > > 
> > > driver, which would suggest that:
> > >  1. It's actually meant to represent WCN3680B, which needs 3.3V vddpa
> > >  
> > >     like WCN3660B, or
> > >  
> > >  2. WCN3680(A?) has different requirements than WCN3660(A?) and also
> > >  
> > >     needs 3.3V vddpa. But then what is the difference between
> > >     WCN3680(A?) and WCN3680B? Is there even a variant without ...B?
> > > 
> > > There is public documentation for WCN3660B and WCN3680B but the non-B
> > > variants are shrouded in mystery.
> > 
> > Hi Stephan (and everyone),
> > 
> > Do you have a suggestion how to move this patchset forward? Is the
> > fallback
> > compatible that was suggested okay for the wcn3680b situation?
> > 
> >   compatible = "qcom,wcn3680b", "qcom,wcn3680";
> > 
> > If so, I'll make v2 with that implemented.
> 
> Personally, I would just go with what exists already and use the
> existing "qcom,wcn3680" compatible as-is. No one has provided evidence
> that there is actually something like a WCN3680(A), without a 'B' at the
> end. Also, all existing users of the "qcom,wcn3680" compatible upstream
> actually seem to refer to WCN3680B (I'm quite sure apq8039-t2 has
> WCN3680B, MSM8974 isn't entirely clear but iirc you mentioned there was
> some schematic of a MSM8974 device which says WCN3680B as well).
> 
> It would be nice to have the compatible perfectly correct and complete,
> but I see no point to extend it with additional information that we
> can't properly verify.
> 
> Or do you actually need a different compatible to customize something in
> the driver?

No it should be fine with qcom,wcn3680.

I'll send v2 in the coming days then, thanks for your input!

Regards
Luca

> 
> Thanks,
> Stephan
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml b/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml
index 45eb42bd3c2c..0e5e0b7a0610 100644
--- a/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml
+++ b/Documentation/devicetree/bindings/remoteproc/qcom,wcnss-pil.yaml
@@ -111,6 +111,7 @@  properties:
           - qcom,wcn3660
           - qcom,wcn3660b
           - qcom,wcn3680
+          - qcom,wcn3680b
 
       clocks:
         minItems: 1