[PATCH 25/34] drm/amd/display: Set the power_down_on_boot function pointer to null

[Melissa Wen]

On 02/28, Mario Limonciello wrote:
> On 2/28/2024 12:39, Alex Hung wrote:
> > From: Muhammad Ahmed <ahmed.ahmed at amd.com>
> > 
> > [WHY]
> > Blackscreen hang @ PC EF000025 when trying to wake up from S0i3. DCN
> > gets powered off due to dc_power_down_on_boot() being called after
> > timeout.
> > 
> > [HOW]
> > Setting the power_down_on_boot function pointer to null since we don't
> > expect the function to be called for APU.
> 
> Perhaps, should we be making the same change for other APUs?

any follow-up to Mario's question?

I wonder if this can help solve other "black screen hangs after suspend"
reported for other APUs...

Melissa

> 
> It seems a few others call dcn10_power_down_on_boot() for the callback.
> 
> > 
> > Cc: Mario Limonciello <mario.limonciello at amd.com>
> > Cc: Alex Deucher <alexander.deucher at amd.com>
> > Cc: stable at vger.kernel.org
> > Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas at amd.com>
> > Acked-by: Alex Hung <alex.hung at amd.com>
> > Signed-off-by: Muhammad Ahmed <ahmed.ahmed at amd.com>
> > ---
> >   drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_init.c | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> > 
> > diff --git a/drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_init.c b/drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_init.c
> > index dce620d359a6..d4e0abbef28e 100644
> > --- a/drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_init.c
> > +++ b/drivers/gpu/drm/amd/display/dc/hwss/dcn35/dcn35_init.c
> > @@ -39,7 +39,7 @@
> >   static const struct hw_sequencer_funcs dcn35_funcs = {
> >   	.program_gamut_remap = dcn30_program_gamut_remap,
> >   	.init_hw = dcn35_init_hw,
> > -	.power_down_on_boot = dcn35_power_down_on_boot,
> > +	.power_down_on_boot = NULL,
> >   	.apply_ctx_to_hw = dce110_apply_ctx_to_hw,
> >   	.apply_ctx_for_surface = NULL,
> >   	.program_front_end_for_ctx = dcn20_program_front_end_for_ctx,
>