[Intel-gfx] [PATCH] drm/i915: Deal with machines that expose less than three QGV points

[Ville Syrjälä]

On Wed, Jul 03, 2019 at 11:01:18AM -0700, Matt Roper wrote:
> On Thu, Jun 06, 2019 at 03:42:10PM +0300, Ville Syrjala wrote:
> > From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > 
> > When SAGV is forced to disabled/min/med/max in the BIOS pcode will
> > only hand us a single QGV point instead of the normal three. Fix
> > the code to deal with that instead declaring the bandwidth limit
> > to be 0 MB/s (and thus preventing any planes from being enabled).
> > 
> > Also shrink the max_bw sturct a bit while at it, and change the
> > deratedbw type to unsigned since the code returns the bw as
> > an unsigned int.
> > 
> > Since we now keep track of how many qgv points we got from pcode
> > we can drop the earlier check added for the "pcode doesn't
> > support the memory subsystem query" case.
> > 
> > Cc: felix.j.degrood at intel.com
> > Cc: Mark Janes <mark.a.janes at intel.com>
> > Cc: Matt Roper <matthew.d.roper at intel.com>
> > Cc: Clint Taylor <Clinton.A.Taylor at intel.com>
> > Fixes: c457d9cf256e ("drm/i915: Make sure we have enough memory bandwidth on ICL")
> > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=110838
> > Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> 
> This one slipped through the cracks, but it looks correct.

Yeah, also disappeared from my own radar due to patchwork getting
confused and moving the patch under Felix's authorship.

> 
> Reviewed-by: Matt Roper <matthew.d.roper at intel.com>

Thanks.

> 
> You'll need to re-spin the patch since intel_bw.c is under the display/
> folder now and enough time has passed that we probably want another CI
> run anyway.

git am is smart enough to deal with file renames usually, and nothing
has changed really so I trust the earlier ci results. Pushed to dinq.

-- 
Ville Syrjälä
Intel