diff options
| author | abdoulaye berthe <abdoulaye.berthe@amd.com> | 2019-09-18 18:57:47 +0300 |
|---|---|---|
| committer | Alex Deucher <alexander.deucher@amd.com> | 2019-11-13 23:29:43 +0300 |
| commit | 903e859b72957985c60de593f364e33639964829 (patch) | |
| tree | 021e753ea4f39dab37a5d92ce8b46c1ac2fc2901 /drivers | |
| parent | 8e5100a575433cc185a2e224280fbd873b6692dd (diff) | |
| download | linux-903e859b72957985c60de593f364e33639964829.tar.xz | |
drm/amd/display: check for dp rev before reading lttpr regs
[Why]
LTTPR was introduced after DP1.2. Reading LTTPR registers 0xFXXXX
on some DP 1.2 display is causing an unexpected behavior.
[How]
Make sure that we don't read any lttpr registers on 1.2 displays.
Signed-off-by: abdoulaye berthe <abdoulaye.berthe@amd.com>
Reviewed-by: Aric Cyr <Aric.Cyr@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c index 2a89f90ef7a7..1e4480f3bd3c 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link_dp.c @@ -2759,9 +2759,10 @@ static bool retrieve_link_cap(struct dc_link *link) /* Set default timeout to 3.2ms and read LTTPR capabilities */ bool ext_timeout_support = link->dc->caps.extended_aux_timeout_support && !link->dc->config.disable_extended_timeout_support; + link->is_lttpr_mode_transparent = true; + if (ext_timeout_support) { status = dc_link_aux_configure_timeout(link->ddc, LINK_AUX_DEFAULT_EXTENDED_TIMEOUT_PERIOD); - link->is_lttpr_mode_transparent = true; } memset(dpcd_data, '\0', sizeof(dpcd_data)); @@ -2796,7 +2797,7 @@ static bool retrieve_link_cap(struct dc_link *link) return false; } - if (ext_timeout_support) { + if (ext_timeout_support && link->dpcd_caps.dpcd_rev.raw >= 0x14) { status = core_link_read_dpcd( link, DP_PHY_REPEATER_CNT, |