Re: [PATCH 4/4] drm/i915: Drop WaIncreaseLatencyIPCEnabled/1140 for cnl

Ville Syrjälä
2019-02-04T17:41:00Z

On Thu, Jan 31, 2019 at 10:10:47AM -0800, Rodrigo Vivi wrote:
> On Thu, Jan 31, 2019 at 09:42:16AM +0200, Ville Syrjala wrote:
> > From: Ville Syrjälä <ville.syrjala@linux.intel.com>
> >
> > Drop WaIncreaseLatencyIPCEnabled/Display w/a #1140 for
> > early cnl steppings. Also switch the kbl/cfl case to check
> > for IS_GEN9_BC() for brevity. It ends up being the same thing
> > because IPC is disabled on SKL due to w/a #0477.
>
> I think this deserves a commend in the code, otherwise someone
> in the future might not notice that and send a patch to replace
> 9_BC per KBL || CFL...
>
> anyway:
>
> Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

Ta. I just noticed there were some other IS_KBL||IS_CFL cases in the
code as well. So maybe I'll just leave it as is here too.

One thing I don't like is that w/a #0477 is in the device info. I think
I'll want to move that into ipc code to make it less confusing what's
going on.

>
>
>
> >
> > Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> > ---
> > drivers/gpu/drm/i915/intel_pm.c | 4 +---
> > 1 file changed, 1 insertion(+), 3 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> > index 306e41ccc50e..55491e2d5134 100644
> > --- a/drivers/gpu/drm/i915/intel_pm.c
> > +++ b/drivers/gpu/drm/i915/intel_pm.c
> > @@ -4701,9 +4701,7 @@ static void skl_compute_plane_wm(const struct intel_crtc_state *cstate,
> > * WaIncreaseLatencyIPCEnabled: kbl,cfl
> > * Display WA #1141: kbl,cfl
> > */
> > - if ((IS_KABYLAKE(dev_priv) || IS_COFFEELAKE(dev_priv) ||
> > - IS_CNL_REVID(dev_priv, CNL_REVID_A0, CNL_REVID_B0)) &&
> > - dev_priv->ipc_enabled)
> > + if (IS_GEN9_BC(dev_priv) && dev_priv->ipc_enabled)
> > latency += 4;
> >
> > if (skl_needs_memory_bw_wa(dev_priv) && wp->x_tiled)
> > --
> > 2.19.2
> >
> > _______________________________________________
> > Intel-gfx mailing list
> > Intel-gfx@lists.freedesktop.org
> > https://lists.freedesktop.org/mailman/listinfo/intel-gfx

--
Ville Syrjälä
Intel