diff options
| author | Brendan Tam <Brendan.Tam@amd.com> | 2025-03-14 20:09:13 +0300 |
|---|---|---|
| committer | Alex Deucher <alexander.deucher@amd.com> | 2025-03-27 00:43:25 +0300 |
| commit | 8058061ed9d6bc259d1e678607b07d259342c08f (patch) | |
| tree | 7841f629048a57dde5230767da6ad289171b0770 /drivers/gpu/drm/amd | |
| parent | 0389f2a3a23c9a2d4cf58d2ab0d3b283f19e8630 (diff) | |
| download | linux-8058061ed9d6bc259d1e678607b07d259342c08f.tar.xz | |
drm/amd/display: prevent hang on link training fail
[Why]
When link training fails, the phy clock will be disabled. However, in
enable_streams, it is assumed that link training succeeded and the
mux selects the phy clock, causing a hang when a register write is made.
[How]
When enable_stream is hit, check if link training failed. If it did, fall
back to the ref clock to avoid a hang and keep the system in a recoverable
state.
Reviewed-by: Dillon Varone <dillon.varone@amd.com>
Signed-off-by: Brendan Tam <Brendan.Tam@amd.com>
Signed-off-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Diffstat (limited to 'drivers/gpu/drm/amd')
| -rw-r--r-- | drivers/gpu/drm/amd/display/dc/hwss/dcn20/dcn20_hwseq.c | 6 | ||||
| -rw-r--r-- | drivers/gpu/drm/amd/display/dc/hwss/dcn401/dcn401_hwseq.c | 7 |
2 files changed, 10 insertions, 3 deletions
diff --git a/drivers/gpu/drm/amd/display/dc/hwss/dcn20/dcn20_hwseq.c b/drivers/gpu/drm/amd/display/dc/hwss/dcn20/dcn20_hwseq.c index 926c08e790c1..846c9c51f2d9 100644 --- a/drivers/gpu/drm/amd/display/dc/hwss/dcn20/dcn20_hwseq.c +++ b/drivers/gpu/drm/amd/display/dc/hwss/dcn20/dcn20_hwseq.c @@ -3033,7 +3033,11 @@ void dcn20_enable_stream(struct pipe_ctx *pipe_ctx) dccg->funcs->set_dpstreamclk(dccg, DTBCLK0, tg->inst, dp_hpo_inst); phyd32clk = get_phyd32clk_src(link); - dccg->funcs->enable_symclk32_se(dccg, dp_hpo_inst, phyd32clk); + if (link->cur_link_settings.link_rate == LINK_RATE_UNKNOWN) { + dccg->funcs->disable_symclk32_se(dccg, dp_hpo_inst); + } else { + dccg->funcs->enable_symclk32_se(dccg, dp_hpo_inst, phyd32clk); + } } else { if (dccg->funcs->enable_symclk_se) dccg->funcs->enable_symclk_se(dccg, stream_enc->stream_enc_inst, diff --git a/drivers/gpu/drm/amd/display/dc/hwss/dcn401/dcn401_hwseq.c b/drivers/gpu/drm/amd/display/dc/hwss/dcn401/dcn401_hwseq.c index 8f5da0ded850..5489f3d431f6 100644 --- a/drivers/gpu/drm/amd/display/dc/hwss/dcn401/dcn401_hwseq.c +++ b/drivers/gpu/drm/amd/display/dc/hwss/dcn401/dcn401_hwseq.c @@ -936,8 +936,11 @@ void dcn401_enable_stream(struct pipe_ctx *pipe_ctx) if (dc_is_dp_signal(pipe_ctx->stream->signal) || dc_is_virtual_signal(pipe_ctx->stream->signal)) { if (dc->link_srv->dp_is_128b_132b_signal(pipe_ctx)) { dccg->funcs->set_dpstreamclk(dccg, DPREFCLK, tg->inst, dp_hpo_inst); - - dccg->funcs->enable_symclk32_se(dccg, dp_hpo_inst, phyd32clk); + if (link->cur_link_settings.link_rate == LINK_RATE_UNKNOWN) { + dccg->funcs->disable_symclk32_se(dccg, dp_hpo_inst); + } else { + dccg->funcs->enable_symclk32_se(dccg, dp_hpo_inst, phyd32clk); + } } else { dccg->funcs->enable_symclk_se(dccg, stream_enc->stream_enc_inst, link_enc->transmitter - TRANSMITTER_UNIPHY_A); |