Re: [PATCH 1/6] dt-bindings: PCI: toshiba,tc9563: Restrict Tx Amplitude, DFE and N_FTS to USP, DSP1 and DSP2

[Manivannan Sadhasivam]

On Mon, Jul 27, 2026 at 10:59:02AM -0500, Alex Elder wrote:
> On 7/25/26 3:59 AM, Manivannan Sadhasivam via B4 Relay wrote:
> > From: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxxxxxxxx>
> > 
> > TC9563 switch allows configuring Tx Amplitude, DFE and N_FTS settings only
> > to USP, DSP1 and DSP2 ports. These settings don't apply to DSP3 and also
> > the integrated Ethernet MAC Endpoint.
> 
> s/and also the/nor its/
> 
> Also I don't know if there is only one Ethernet MAC here, but
> the TC9564 has two, so maybe make "MAC Endpoint" plural.
> 
> > 
> > So restrict these properties and also move the
> > 'toshiba,tx-amplitude-microvolt' property to DSP2 in the example to conform
> > to the binding.
> > 
> > Fixes: 26f3ac884835 ("dt-bindings: PCI: Add binding for Toshiba TC9563 PCIe switch")
> > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxxxxxxxx>
> 
> I have some other questions with implied suggestions below, but
> this looks good to me.
> 
> Acked-by: Alex Elder <elder@xxxxxxxxxxxx>
> 
> > ---
> >   .../devicetree/bindings/pci/toshiba,tc9563.yaml     | 21 ++++++++++++++++++---
> >   1 file changed, 18 insertions(+), 3 deletions(-)
> > 
> > diff --git a/Documentation/devicetree/bindings/pci/toshiba,tc9563.yaml b/Documentation/devicetree/bindings/pci/toshiba,tc9563.yaml
> > index b3ad05d90201..f084830c6d0c 100644
> > --- a/Documentation/devicetree/bindings/pci/toshiba,tc9563.yaml
> > +++ b/Documentation/devicetree/bindings/pci/toshiba,tc9563.yaml
> > @@ -54,7 +54,7 @@ properties:
> >             - description: I2C slave address
> >   patternProperties:
> > -  "^pcie@[1-3],0$":
> > +  "^pcie@[1-2],0$":
> >       description:
> >         child nodes describing the internal downstream ports of
> >         the tc9563 switch.
> 
> Can you offer any explanation about why the settings apply to these
> two downstream ports but not the third?  (I think it's because the
> third has a different type of link to the endpoint.)
> 

There was no explanation provided in the manual or in the application note. But
since these are PHY related tunings and the VDSP has an integrated MAC Endpoint,
these tunings are irrelevant.

> > @@ -64,6 +64,21 @@ patternProperties:
> >         - $ref: /schemas/pci/pci-pci-bridge.yaml#
> >       unevaluatedProperties: false
> > +  "^pcie@[3],0$":
> 
> Can this just be "^pcie@3,0$"?
> 
> Is there any need to define "^pcie@3,1" for the second PCI function?
> 

Good question. I tried "^pcie@3,0$" first, but it throwed the dt_binding_check
error:

/home/mani/tc9563-fix/Documentation/devicetree/bindings/pci/toshiba,tc9563.yaml:
patternProperties: '^pcie@3,0$' should not be valid under {'pattern': '^\\^[a-zA-Z0-9,\\-._#@]+\\$$'}
        hint: Fixed strings belong in 'properties', not 'patternProperties'

Looks like the schema doesn't allow fixed strings in patternProperties. So I
used regex, just to satisfy the requirement.

- Mani

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