RE: [PATCH] drm/amd/display: Shorten delay time to 1us while resetting FIFO
[Public] Thank you all for the review. I've found a better solution here, so I will retire this patch, and re-submit a different one. Thanks, Zhan > -Original Message- > From: Liu, Zhan > Sent: 2022/January/19, Wednesday 5:24 PM > To: Liu, Zhan ; amd-gfx@lists.freedesktop.org > Cc: Liu, Charlene ; Kotarac, Pavle > ; Pierre-Loup Griffais ; > Gutierrez, Agustin ; Cornij, Nikola > > Subject: RE: [PATCH] drm/amd/display: Shorten delay time to 1us while > resetting > FIFO > > [Public] > > Apologize for sending out the patch with the wrong sensitivity a few seconds > ago. > I've updated sensitivity policy to "Public" here. > > Thanks, > Zhan > > > -Original Message- > > From: amd-gfx On Behalf Of > > Liu, Zhan > > Sent: 2022/January/19, Wednesday 5:19 PM > > To: amd-gfx@lists.freedesktop.org > > Cc: Liu, Charlene ; Kotarac, Pavle > > ; Pierre-Loup Griffais > > ; Gutierrez, Agustin > > ; Cornij, Nikola > > Subject: [PATCH] drm/amd/display: Shorten delay time to 1us while > > resetting FIFO > > > > [Why] > > Current FIFO reset delay for dcn10 is 100us, which is too long and > > will fail atomic flip. As a result, there will be no display on boot. > > > > [How] > > Shorten delay time to 1us. This also aligns with FIFO reset delay on other > > ASICs. > > > > Signed-off-by: Zhan Liu > > --- > > drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git > > a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c > > b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c > > index bf4436d7aaab..2077c22befa5 100644 > > --- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c > > +++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c > > @@ -909,7 +909,7 @@ void enc1_stream_encoder_reset_fifo( > > > > /* set DIG_START to 0x1 to reset FIFO */ > > REG_UPDATE(DIG_FE_CNTL, DIG_START, 1); > > - udelay(100); > > + udelay(1); > > > > /* write 0 to take the FIFO out of reset */ > > REG_UPDATE(DIG_FE_CNTL, DIG_START, 0); > > -- > > 2.25.1
RE: [PATCH] drm/amd/display: Shorten delay time to 1us while resetting FIFO
[Public] Apologize for sending out the patch with the wrong sensitivity a few seconds ago. I've updated sensitivity policy to "Public" here. Thanks, Zhan > -Original Message- > From: amd-gfx On Behalf Of Liu, Zhan > Sent: 2022/January/19, Wednesday 5:19 PM > To: amd-gfx@lists.freedesktop.org > Cc: Liu, Charlene ; Kotarac, Pavle > ; Pierre-Loup Griffais ; > Gutierrez, Agustin ; Cornij, Nikola > > Subject: [PATCH] drm/amd/display: Shorten delay time to 1us while resetting > FIFO > > [Why] > Current FIFO reset delay for dcn10 is 100us, which is too long and will fail > atomic > flip. As a result, there will be no display on boot. > > [How] > Shorten delay time to 1us. This also aligns with FIFO reset delay on other > ASICs. > > Signed-off-by: Zhan Liu > --- > drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c > b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c > index bf4436d7aaab..2077c22befa5 100644 > --- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c > +++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c > @@ -909,7 +909,7 @@ void enc1_stream_encoder_reset_fifo( > > /* set DIG_START to 0x1 to reset FIFO */ > REG_UPDATE(DIG_FE_CNTL, DIG_START, 1); > - udelay(100); > + udelay(1); > > /* write 0 to take the FIFO out of reset */ > REG_UPDATE(DIG_FE_CNTL, DIG_START, 0); > -- > 2.25.1
Re: [PATCH] drm/amd/display: Shorten delay time to 1us while resetting FIFO
Acked-by: Alex Deucher On Wed, Jan 19, 2022 at 5:19 PM Liu, Zhan wrote: > > [AMD Official Use Only] > > [Why] > Current FIFO reset delay for dcn10 is 100us, which is too long > and will fail atomic flip. As a result, there will be no display > on boot. > > [How] > Shorten delay time to 1us. This also aligns with FIFO reset delay > on other ASICs. > > Signed-off-by: Zhan Liu > --- > drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c > b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c > index bf4436d7aaab..2077c22befa5 100644 > --- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c > +++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c > @@ -909,7 +909,7 @@ void enc1_stream_encoder_reset_fifo( > > /* set DIG_START to 0x1 to reset FIFO */ > REG_UPDATE(DIG_FE_CNTL, DIG_START, 1); > - udelay(100); > + udelay(1); > > /* write 0 to take the FIFO out of reset */ > REG_UPDATE(DIG_FE_CNTL, DIG_START, 0); > -- > 2.25.1
