Re: [PATCH v2 00/12] arm64: dts: qcom: sc8280xp: PCIe fixes and GICv3 ITS enable

[Johan Hovold <johan@kernel.org>]

On Thu, Feb 29, 2024 at 07:24:07PM +0530, Manivannan Sadhasivam wrote:
> On Thu, Feb 29, 2024 at 02:10:21PM +0100, Johan Hovold wrote:

> > I think that based on the available data it's reasonable to go ahead and
> > merge these patches. In the event that this turns out to be a
> > configuration issue, we can just drop the 'aspm-no-l0s' properties
> > again.
> 
> Well the problem is, if you are not sure, then adding the DT properties is
> certainly not correct. As that implies a hardware defect, but it may not be.
> So let's wait for some time to find out the actual issue.

Our devicetrees are always going to be a tentative description of the
hardware, and this especially true for Qualcomm that don't publish any
documentation so that people are forced to rely on informed guesses
based on downstream devicetrees and drivers and reverse engineering.

As far as I can tell, after having spent a lot of time on this and
checking with sources inside Qualcomm, the hardware is to blame here. If
this turns out not to be true, we can always revise later. We do this
all the time, as you know.

I'm all for digging further into this issue with the help of Qualcomm,
but I don't think that should block this series as that would leave the
link errors that we hit since 6.7 in place and effectively prevent us
from enabling the ITS in 6.9.

Johan