[igt-dev] [PATCH i-g-t] tests/kms_dp_dsc: Force a full modeset when we force dsc enable

[Imre Deak]

On Wed, Apr 03, 2019 at 11:20:58AM -0700, Manasi Navare wrote:
> On Wed, Apr 03, 2019 at 04:25:10PM +0300, Imre Deak wrote:
> > On Tue, Apr 02, 2019 at 12:31:19PM -0700, Manasi Navare wrote:
> > > DSC enable gets configured during compute_config and needs
> > > a full modeset to force DSC.
> > > Sometimes in between the tests, if the initial output is same as the
> > > mode being set for DSC then it will not do a full modeset.
> > > So we disable the output before forcing a mode with DSC enable.
> > > 
> > > Fixes: db19bccc1c22 ("test/kms_dp_dsc: Basic KMS test to validate VESA DSC on DP/eDP")
> > > Cc: Petri Latvala <petri.latvala at intel.com>
> > > Cc: Anusha Srivatsa <anusha.srivatsa at intel.com>
> > > Cc: Imre Deak <imre.deak at intel.com>
> > > Signed-off-by: Manasi Navare <manasi.d.navare at intel.com>
> > > ---
> > >  tests/kms_dp_dsc.c | 7 ++++++-
> > >  1 file changed, 6 insertions(+), 1 deletion(-)
> > > 
> > > diff --git a/tests/kms_dp_dsc.c b/tests/kms_dp_dsc.c
> > > index da93cd74..f3a61029 100644
> > > --- a/tests/kms_dp_dsc.c
> > > +++ b/tests/kms_dp_dsc.c
> > > @@ -174,6 +174,11 @@ static void update_display(data_t *data, enum dsc_test_type test_type)
> > >  				      &data->fb_test_pattern);
> > >  		primary = igt_output_get_plane_type(data->output,
> > >  						    DRM_PLANE_TYPE_PRIMARY);
> > > +		/* Disable the output first */
> > > +		igt_plane_set_fb(primary, NULL);
> > 
> > I think no need to reset the plane, it's enough to set PIPE_NONE to turn
> > off the output.
> > 
> > > +		igt_output_set_pipe(data->output, PIPE_NONE);
> > 
> > You are missing here the additional commit needed to turn off the output
> > and then set back the output to data->pipe before the commit below. The
> > igt_output_set_pipe() call in run_test() won't be needed either.
> 
> Oh I looked through all the other kms tests and there we always set
> the fb for PRIMARY plane to NULL then set the pipe to NULL.  But I
> guess if we disable to pipe output, the plane if its NULL or not
> shouldnt really matter.  So I should just have:
> 
> igt_plane_set_fb(primary, NULL);
> igt_display_commit(&data->display);

You need to set PIPE_NONE before the commit and then the actual pipe
before the rest of the sequence, like:

	igt_debug("DSC is supported on %s\n", data->conn_name);

	igt_output_set_pipe(data->output, PIPE_NONE);
	igt_display_commit(&data->display);

	force_dp_dsc_enable(...);

	igt_output_set_pipe(data->output, data->pipe);
	igt_create_pattern_fb(...);
	primary = ...
	igt_plane_set_fb(...);
	igt_display_commit(&data->display);

> Then set fb to the test pattern and display commit to set output to
> the desired mode corerct?
> 

> So why is it that I wont need the igt_output_set_pipe(output, pipe) in
> run_test()?  I see that all the kms tests use this call
> for_each_valid_output_on_pipe iterator

Because you will anyway set it to PIPE_NONE right afterwards in
update_display().

> > > +
> > > +		/* Now set the output to the desired mode */
> > >  		igt_plane_set_fb(primary, &data->fb_test_pattern);
> > >  		igt_display_commit(&data->display);
> > >  
> > > @@ -187,7 +192,7 @@ static void update_display(data_t *data, enum dsc_test_type test_type)
> > >  		clear_dp_dsc_enable(data);
> > 
> > Instead of this we should restore the original value of
> > i915_dsc_fec_support and also make sure we restore it if the test fails
> > and aborts somewhere before this call. Take a look at a look at the
> > various places changing debugfs entries that call
> > igt_install_exit_handler() for an idea how to do this.
> 

> So save the original value of i915_dsc_fec_support() and restore that
> in test_cleanup()

Save the original value in force_dp_dsc_enable() and restore it in a new
restore_dp_dsc_enable() which you call instead of clear_dp_dsc_enable()
in update_display().

> and in the igt_fixture(), have:
> kmstest_set_vt_graphics_mode();
> igt_install_exit_handler()

The exit handler should be installed only after saving the original
value, so the handler will have the proper value to restore. Save/install
the exit handler only once even if force_dp_dsc_enable() is called
multiple times.

> 
> Manasi
> 
> > 
> > >  
> > >  		igt_assert_f(enabled,
> > > -			     "Default DSC enable failed on Connector: %s Pipe: %s",
> > > +			     "\nDefault DSC enable failed on Connector: %s Pipe: %s",
> > >  			     data->conn_name,
> > >  			     kmstest_pipe_name(data->pipe));
> > >  	} else {
> > > -- 
> > > 2.19.1
> > >