diff options
| author | Nikola Cornij <nikola.cornij@amd.com> | 2019-11-11 18:03:59 -0500 |
|---|---|---|
| committer | Alex Deucher <alexander.deucher@amd.com> | 2019-12-05 18:19:54 -0500 |
| commit | 87de6cb2f28153bc74d0a001ca099c29453e145f (patch) | |
| tree | 7f0333488272f8e88faa2559c2bd8358c1666032 /drivers/gpu/drm | |
| parent | a2a1f1eb06d73a45a60970c77403687918966fc6 (diff) | |
| download | linux-87de6cb2f28153bc74d0a001ca099c29453e145f.tar.bz2 | |
drm/amd/display: Reset steer fifo before unblanking the stream
[why]
During mode transition steer fifo could overflow. Quite often it
recovers by itself, but sometimes it doesn't.
[how]
Add steer fifo reset before unblanking the stream. Also add a short
delay when resetting dig resync fifo to make sure register writes
don't end up back-to-back, in which case the HW might miss the reset
request.
Signed-off-by: Nikola Cornij <nikola.cornij@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Diffstat (limited to 'drivers/gpu/drm')
| -rw-r--r-- | drivers/gpu/drm/amd/display/dc/dcn20/dcn20_stream_encoder.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_stream_encoder.c b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_stream_encoder.c index 4b3401616434..fcb3877b4fcb 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_stream_encoder.c +++ b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_stream_encoder.c @@ -492,15 +492,23 @@ void enc2_stream_encoder_dp_unblank( DP_VID_N_MUL, n_multiply); } - /* set DIG_START to 0x1 to reset FIFO */ + /* make sure stream is disabled before resetting steer fifo */ + REG_UPDATE(DP_VID_STREAM_CNTL, DP_VID_STREAM_ENABLE, false); + REG_WAIT(DP_VID_STREAM_CNTL, DP_VID_STREAM_STATUS, 0, 10, 5000); + /* set DIG_START to 0x1 to reset FIFO */ REG_UPDATE(DIG_FE_CNTL, DIG_START, 1); + udelay(1); /* write 0 to take the FIFO out of reset */ REG_UPDATE(DIG_FE_CNTL, DIG_START, 0); - /* switch DP encoder to CRTC data */ + /* switch DP encoder to CRTC data, but reset it the fifo first. It may happen + * that it overflows during mode transition, and sometimes doesn't recover. + */ + REG_UPDATE(DP_STEER_FIFO, DP_STEER_FIFO_RESET, 1); + udelay(10); REG_UPDATE(DP_STEER_FIFO, DP_STEER_FIFO_RESET, 0); |