Re: [PATCH net-next 1/5] dt-bindings: net: qcom,ipa: deprecate modem-init

[Alex Elder]

On 11/14/22 03:56, Krzysztof Kozlowski wrote:
> On 12/11/2022 21:07, Alex Elder wrote:
> > GSI firmware for IPA must be loaded during initialization, either by
> > the AP or by the modem.  The loader is currently specified based on
> > whether the Boolean modem-init property is present.
> >
> > Instead, use a new property with an enumerated value to indicate
> > explicitly how GSI firmware gets loaded.  With this in place, a
> > third approach can be added in an upcoming patch.
> >
> > The new qcom,gsi-loader property has two defined values:
> >    - self:   The AP loads GSI firmware
> >    - modem:  The modem loads GSI firmware
> > The modem-init property must still be supported, but is now marked
> > deprecated.
> >
> > Signed-off-by: Alex Elder <elder@xxxxxxxxxx>
> > ---
> >   .../devicetree/bindings/net/qcom,ipa.yaml     | 59 +++++++++++++++----
> >   1 file changed, 46 insertions(+), 13 deletions(-)
> >
> > diff --git a/Documentation/devicetree/bindings/net/qcom,ipa.yaml b/Documentation/devicetree/bindings/net/qcom,ipa.yaml
> > index e752b76192df0..0dfd6c721e045 100644
> > --- a/Documentation/devicetree/bindings/net/qcom,ipa.yaml
> > +++ b/Documentation/devicetree/bindings/net/qcom,ipa.yaml
> > @@ -124,12 +124,22 @@ properties:
> >         - const: ipa-clock-enabled-valid
> >         - const: ipa-clock-enabled
> >   
> > +  qcom,gsi-loader:
> > +    enum:
> > +      - self
> > +      - modem
> > +    description:
> > +      This indicates how GSI firmware should be loaded.  If the AP loads
>
> s/This indicates/Indicate/
> (or any other grammar without describing DT syntax but hardware/system)

OK.

> > +      and validates GSI firmware, this property has value "self".  If the
> > +      modem does this, this property has value "modem".
> > +
> >     modem-init:
> > +    deprecated: true
> >       type: boolean
> >       description:
> > -      If present, it indicates that the modem is responsible for
> > -      performing early IPA initialization, including loading and
> > -      validating firwmare used by the GSI.
> > +      This is the older (deprecated) way of indicating how GSI firmware
> > +      should be loaded.  If present, the modem loads GSI firmware; if
> > +      absent, the AP loads GSI firmware.
> >   
> >     memory-region:
> >       maxItems: 1
> > @@ -155,15 +165,36 @@ required:
> >     - interconnects
> >     - qcom,smem-states
> >   
> > -# If modem-init is not present, the AP loads GSI firmware, and
> > -# memory-region must be specified
> > -if:
> > -  not:
> > -    required:
> > -      - modem-init
> > -then:
> > -  required:
> > -    - memory-region
> > +allOf:
> > +  # If qcom,gsi-loader is present, modem-init must not be present
> > +  - if:
> > +      required:
> > +        - qcom,gsi-loader
> > +    then:
> > +      properties:
> > +        modem-init: false
>
> This is ok, but will not allow you to keep deprecated property in DTS
> for the transition period. We talked about this that you need to keep
> both or wait few cycles before applying DTS cleanups.

My intention is expressed in the comment.  Is it because of the
"if .... required ... qcom,gsi-loader"?

Should it be "if ... properties ... qcom,gsi-loader"?

I believe I tested the deprecated cases also, but will do it again.
If I coded it wrong I'd like to fix it (even if "it works").

> > +
> > +      # If qcom,gsi-loader is "self", the AP loads GSI firmware, and
> > +      # memory-region must be specified
> > +      if:
> > +        properties:
> > +          qcom,gsi-loader:
> > +            contains:
> > +              const: self
> > +      then:
> > +        required:
> > +          - memory-region
> > +    else:
> > +      # If qcom,gsi-loader is not present, we use deprecated behavior.
> > +      # If modem-init is not present, the AP loads GSI firmware, and
> > +      # memory-region must be specified.
> > +      if:
> > +        not:
> > +          required:
> > +            - modem-init
> > +      then:
> > +        required:
> > +          - memory-region
> >   
> >   additionalProperties: false
> >   
> > @@ -196,7 +227,9 @@ examples:
> >           ipa@1e40000 {
> >                   compatible = "qcom,sdm845-ipa";
> >   
> > -                modem-init;
> > +                qcom,gsi-loader = "self";
> > +                memory-region = <&ipa_fw_mem>;
> > +                firmware-name = "qcom/sc7180-trogdor/modem-nolte/mba.mbn";
>
> Isn't this example based on sdm845?

Yes, you're right.  I'll update it.  I just wanted to supply an
example that actually showed using all these properties.  I'll
make the whole example be for sc7180.

Thank you.

					-Alex

> >   
> >                   iommus = <&apps_smmu 0x720 0x3>;
> >                   reg = <0x1e40000 0x7000>,
>
> Best regards,
> Krzysztof