Re: [PATCH] arm64: dts: renesas: spider: Add overlay for PCIe ch0 endpoint mode

[Koichiro Den]

On Fri, Oct 23, 2026 at 02:58:38AM +0200, Marek Vasut wrote:
> On 10/22/26 10:21 AM, Koichiro Den wrote:
> 
> Hello Den-san,
> 
> [...]
> 
> > +++ b/arch/arm64/boot/dts/renesas/r8a779f0-spider-pcie0-ep.dtso
> > @@ -0,0 +1,15 @@
> > +// SPDX-License-Identifier: (GPL-2.0 OR MIT)
> > +/*
> > + * Copyright (C) 2026 Renesas Electronics Corp.
> 
> Is this header correct ?

I checked with Renesas just in case, and confirmed it is fine.

> 
> Would it be possible to include a brief "example usage" comment in the
> header ? An example of such a comment is available in e.g.
> arch/arm64/boot/dts/renesas/r8a779g3-sparrow-hawk-fan-argon40.dtso "Example
> usage:" . If this would be too complicated, then please ignore this request.

I would personally perfer to stay aligned with other in-tree PCIe endpoint
overlays (e.g. freescale/imx*, rockchip/*, ti/k3-*) rather than adding
fan/HAT-style examples here.

The typical (long-standing) usage would just be the standard configfs steps for
pci-epf-test (documented in Documentation/PCI/endpoint/pci-test-howto.rst), so I
suspect duplicating those generic instructions in this file might not add much
value.

That said, keeping the header completely bare might look too terse.
How about something like this:

  // SPDX-License-Identifier: (GPL-2.0 OR MIT)
  /*
   * DT Overlay for enabling PCIe channel 0 in Endpoint Configuration with the
   * R-Car S4-8 Spider board.
   *
   * Copyright (C) 2026 Renesas Electronics Corp.
   */

Thank you for the review!

Best regards,
Koichiro Den

> 
> Thank you for your help !
> 
> -- 
> Best regards,
> Marek Vasut