On Mon, Aug 01, 2022 at 11:56:36AM -0600, Rob Herring wrote:
> On Thu, Jul 28, 2022 at 05:34:13PM +0300, Serge Semin wrote:
> > It's normal to have the DW PCIe RP/EP DT-nodes equipped with the explicit
> > PHY phandle references. There can be up to 16 PHYs attach in accordance
> > with the maximum number of supported PCIe lanes. Let's extend the common
> > DW PCIe controller schema with the 'phys' and 'phy-names' properties
> > definition. The PHY names are defined with the regexp pattern
> > '^pcie([0-9]+|-?phy[0-9]*)?$' so to match the names currently supported by
> > the DW PCIe platform drivers ("pcie": meson; "pciephy": qcom, imx6;
> > "pcie-phy": uniphier, rockchip, spear13xx; "pcie": intel-gw; "pcie-phy%d":
> > keystone, dra7xx; "pcie": histb, etc). Though the "pcie%d" format would
> > the most preferable in this case.
>
> No phy-names is my preference. Some string plus an index is utterly
> pointless. Oh well...
Mine too, but we have no choice in this case since the named
PHY-properties support has already been advertised by the platform
drivers. This patch just provides the bindings for them. Just note
the string patterns have been designed in a way to match these bindings.
Anyway thanks for telling about the preferred option. Keeping that in
mind I won't have doubts what approach to select for the new
driver/bindings development.
>
> >
> > Signed-off-by: Serge Semin <Sergey.Semin@xxxxxxxxxxxxxxxxxxxx>
> >
> > ---
> >
> > Changelog v3:
> > - This is a new patch unpinned from the next one:
> > https://lore.kernel.org/linux-pci/20220503214638.1895-2-Sergey.Semin@xxxxxxxxxxxxxxxxxxxx/
> > by the Rob' request. (@Rob)
> > ---
> > .../bindings/pci/snps,dw-pcie-common.yaml | 15 +++++++++++++++
> > .../devicetree/bindings/pci/snps,dw-pcie-ep.yaml | 3 +++
> > .../devicetree/bindings/pci/snps,dw-pcie.yaml | 3 +++
> > 3 files changed, 21 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/pci/snps,dw-pcie-common.yaml b/Documentation/devicetree/bindings/pci/snps,dw-pcie-common.yaml
> > index 3e992b653d12..627a5d6625ba 100644
> > --- a/Documentation/devicetree/bindings/pci/snps,dw-pcie-common.yaml
> > +++ b/Documentation/devicetree/bindings/pci/snps,dw-pcie-common.yaml
> > @@ -17,6 +17,21 @@ description:
> > select: false
> >
> > properties:
> > + phys:
> > + description:
> > + There can be up to the number of possible lanes PHYs specified.
>
> This needs something about being in order of lane number.
Ok.
>
> > + Obviously each specified PHY is supposed to be able to work in the
> > + PCIe mode with a speed implied by the DWC PCIe controller it is
> > + attached to.
> > + minItems: 1
> > + maxItems: 16
> > +
> > + phy-names:
> > + minItems: 1
> > + maxItems: 16
> > + items:
> > + pattern: '^pcie([0-9]+|-?phy[0-9]*)?$'
>
> Please comment here that pcie[0-9] is the preferred form.
What about a bit more sophisticated update?
phy-names:
minItems: 1
maxItems: 16
oneOf:
- items:
pattern: '^pcie[0-9]+$'
- deprecated: true
items:
pattern: '^pcie(-?phy[0-9]*)?$'
-Sergey
>
> Rob
