diff options
| author | Imre Deak | 2021-03-17 20:49:01 +0200 |
|---|---|---|
| committer | Rodrigo Vivi | 2021-03-23 08:26:59 -0400 |
| commit | ab03631087f5c296030dd86265ea02dcdacc6802 (patch) | |
| tree | f7e19a04aa7310fc7faf7f483e81f6b1df813989 /drivers | |
| parent | 7dffbdedb96a076843719d4ea5b2cd666481c416 (diff) | |
drm/i915: Disable LTTPR support when the LTTPR rev < 1.4
By the specification the 0xF0000 - 0xF02FF range is only valid if the
LTTPR revision at 0xF0000 is at least 1.4. Disable the LTTPR support
otherwise.
Fixes: 7b2a4ab8b0ef ("drm/i915: Switch to LTTPR transparent mode link training")
Cc: <stable@vger.kernel.org> # v5.11
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210317184901.4029798-4-imre.deak@intel.com
(cherry picked from commit 1663ad4936e0679443a315fe342f99636a2420dd)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/gpu/drm/i915/display/intel_dp_link_training.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_dp_link_training.c b/drivers/gpu/drm/i915/display/intel_dp_link_training.c index c10e81a3d64f..be6ac0dd846e 100644 --- a/drivers/gpu/drm/i915/display/intel_dp_link_training.c +++ b/drivers/gpu/drm/i915/display/intel_dp_link_training.c @@ -99,17 +99,23 @@ static bool intel_dp_read_lttpr_common_caps(struct intel_dp *intel_dp) return false; if (drm_dp_read_lttpr_common_caps(&intel_dp->aux, - intel_dp->lttpr_common_caps) < 0) { - intel_dp_reset_lttpr_common_caps(intel_dp); - return false; - } + intel_dp->lttpr_common_caps) < 0) + goto reset_caps; drm_dbg_kms(&dp_to_i915(intel_dp)->drm, "LTTPR common capabilities: %*ph\n", (int)sizeof(intel_dp->lttpr_common_caps), intel_dp->lttpr_common_caps); + /* The minimum value of LT_TUNABLE_PHY_REPEATER_FIELD_DATA_STRUCTURE_REV is 1.4 */ + if (intel_dp->lttpr_common_caps[0] < 0x14) + goto reset_caps; + return true; + +reset_caps: + intel_dp_reset_lttpr_common_caps(intel_dp); + return false; } static bool |