[PATCH 1/2] drm/amdgpu: Move HDP remapping earlier during init

[Bjorn Helgaas]

[+cc Greg, no action needed yet, just FYI that stable will want these]

On Thu, Aug 25, 2022 at 02:28:19PM +0530, Lijo Lazar wrote:
> HDP flush is used early in the init sequence as part of memory controller
> block initialization. Hence remapping of HDP registers needed for flush
> needs to happen earlier.
> 
> This also fixes the AER error reported as Unsupported Request during
> driver load.

I would say something like:

  This prevents writes to unimplemented space, which would cause
  Unsupported Request errors.  Prior to 8795e182b02d ("PCI/portdrv:
  Don't disable AER reporting in get_port_device_capability()"), these
  errors occurred but were ignored.

The write is the error; AER is just the reporting mechanism.

> Link: https://bugzilla.kernel.org/show_bug.cgi?id=216373

We need a cc: stable because 8795e182b02d ("PCI/portdrv: Don't disable
AER reporting in get_port_device_capability()") has already been
backported to at lealst these stable kernels:

  5.10.137 5.15.61 5.18.18 5.19.2

and these fixes need to go there as well.  So add something like this:

  Fixes: 8795e182b02d ("PCI/portdrv: Don't disable AER reporting in get_port_device_capability()")
  cc: stable at vger.kernel.org

It's not that there was something wrong with 8795e182b02d and these
patches fix it; it's just that 8795e182b02d *exposed* an amdgpu
problem that was there all along.  But we need some way to connect
with it.

> Reported-by: Tom Seewald <tseewald at gmail.com>
> Signed-off-by: Lijo Lazar <lijo.lazar at amd.com>