Re: [PATCH 1/3] dt-bindings: PCI: cdns: Add PHY latency properties

From: Bjorn Helgaas
Date: Thu Oct 13 2022 - 15:32:29 EST


On Thu, Oct 13, 2022 at 02:12:49PM -0500, Rob Herring wrote:
> On Thu, Oct 13, 2022 at 08:26:47AM +0200, Dominic Rath wrote:
> > From: Alexander Bahle <bahle@xxxxxxxxxxxxxxx>
> >
> > Add "cdns,tx-phy-latency-ps" and "cdns,rx-phy-latency-ps" DT bindings for
> > setting the PCIe PHY latencies.
> > The properties expect a list of uint32 PHY latencies in picoseconds for
> > every supported speed starting at PCIe Gen1, e.g.:
> >
> > max-link-speed = <2>;
> > tx-phy-latency-ps = <100000 200000>; /* Gen1: 100ns, Gen2: 200ns */
> > rx-phy-latency-ps = <150000 250000>; /* Gen1: 150ns, Gen2: 250ns */
> ...

> If PTM is a standard PCIe thing, then I don't think these should be
> Cadence specific. IOW, drop 'cdns'.

PTM is definitely a standard PCIe thing. I had the same question.