Re: [Intel-gfx] [PATCH 4/4] DO_NOT_MERGE: drm/i915/display: Enable PSR2 selective fetch by default

["Souza, Jose" <jose.souza@intel.com>]

On Tue, 2021-08-03 at 14:17 +0300, Gwan-gyeong Mun wrote:
> 
> On 7/31/21 3:10 AM, José Roberto de Souza wrote:
> > Only to execute tests with PSR2 selective fetch enabled and check what
> > is broken.
> > 
> > IGT tests know to fail with this:
> > - kms_cursor_legacy: all tests that checks if evasion happend, I have
> > fix for it making cursor_slowpath() returns true for display 12+.
> > 
> > - kms_psr2_su: The pageflip test, it needs to have the damage clip set
> > otherwise it will update the whole screen and the selective blocks
> > will not match with expected.
> > 
> kms_psr2_su is a test case for intel PSR2 HW tracking and kms_psr2_sf is 
> used as a test for intel PSR2 manual tracking. Is it necessary to modify 
> kms_psr2_su for testing PSR2 manual tracking?

kms_psr2_su is to test that PSR2 is sending selective updates, just adding a couple of lines we can make it work with selective fetch.

> > - kms_psr: psr2_*_(mmap_gtt, mmap_cpu, blt and render), all those
> > tests should be dropped or skipped for display 12+.
> > 
> Could you explain in more detail why we need to skip on display 12+?

This are stuff that would end up calling intel_psr_invalidate/flush().

> 
> > Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
> > ---
> >   drivers/gpu/drm/i915/display/intel_psr.c | 9 ---------
> >   drivers/gpu/drm/i915/i915_params.h       | 2 +-
> >   2 files changed, 1 insertion(+), 10 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/display/intel_psr.c b/drivers/gpu/drm/i915/display/intel_psr.c
> > index 894a2d35668a2..e128f0c2aeecc 100644
> > --- a/drivers/gpu/drm/i915/display/intel_psr.c
> > +++ b/drivers/gpu/drm/i915/display/intel_psr.c
> > @@ -877,15 +877,6 @@ static bool intel_psr2_config_valid(struct intel_dp *intel_dp,
> >   		return false;
> >   	}
> >   
> > -	/*
> > -	 * We are missing the implementation of some workarounds to enabled PSR2
> > -	 * in Alderlake_P, until ready PSR2 should be kept disabled.
> > -	 */
> > -	if (IS_ALDERLAKE_P(dev_priv)) {
> > -		drm_dbg_kms(&dev_priv->drm, "PSR2 is missing the implementation of workarounds\n");
> > -		return false;
> > -	}
> > -
> >   	if (!transcoder_has_psr2(dev_priv, crtc_state->cpu_transcoder)) {
> >   		drm_dbg_kms(&dev_priv->drm,
> >   			    "PSR2 not supported in transcoder %s\n",
> > diff --git a/drivers/gpu/drm/i915/i915_params.h b/drivers/gpu/drm/i915/i915_params.h
> > index f27eceb82c0f5..8d725b64592d8 100644
> > --- a/drivers/gpu/drm/i915/i915_params.h
> > +++ b/drivers/gpu/drm/i915/i915_params.h
> > @@ -55,7 +55,7 @@ struct drm_printer;
> >   	param(int, enable_fbc, -1, 0600) \
> >   	param(int, enable_psr, -1, 0600) \
> >   	param(bool, psr_safest_params, false, 0400) \
> > -	param(bool, enable_psr2_sel_fetch, false, 0400) \
> > +	param(bool, enable_psr2_sel_fetch, true, 0400) \
> >   	param(int, disable_power_well, -1, 0400) \
> >   	param(int, enable_ips, 1, 0600) \
> >   	param(int, invert_brightness, 0, 0600) \
> >