diff options
| author | Jani Nikula <jani.nikula@intel.com> | 2017-05-18 13:10:25 +0200 |
|---|---|---|
| committer | Jani Nikula <jani.nikula@intel.com> | 2017-05-29 12:43:47 +0200 |
| commit | b31e85eda38c58cae986162ae2c462b53b0a2065 (patch) | |
| tree | 5f7c60ad4e74c0d7c53d089b9f712ae6bd8d63f4 /drivers/gpu/drm/i915/intel_dp.c | |
| parent | drm/dp: start a DPCD based DP sink/branch device quirk database (diff) | |
| download | linux-b31e85eda38c58cae986162ae2c462b53b0a2065.tar.xz linux-b31e85eda38c58cae986162ae2c462b53b0a2065.zip | |
drm/i915: Detect USB-C specific dongles before reducing M and N
The Analogix 7737 DP to HDMI converter requires reduced M and N values
when to operate correctly at HBR2. We tried to reduce the M/N values for
all devices in commit 9a86cda07af2 ("drm/i915/dp: reduce link M/N
parameters"), but that regressed some other sinks. Detect this IC by its
OUI value of 0x0022B9 via the DPCD quirk list, and only reduce the M/N
values for that.
v2 by Jani: Rebased on the DP quirk database
v3 by Jani: Rebased on the reworked DP quirk database
v4 by Jani: Improve commit message (Daniel)
Fixes: 9a86cda07af2 ("drm/i915/dp: reduce link M/N parameters")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=93578
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=100755
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Clint Taylor <clinton.a.taylor@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/2d2e30f8f47d3f28c9b74ca2612336a54585c3ec.1495105635.git.jani.nikula@intel.com
Diffstat (limited to 'drivers/gpu/drm/i915/intel_dp.c')
| -rw-r--r-- | drivers/gpu/drm/i915/intel_dp.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 5ce45d98da78..fc691b8b317c 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -1593,6 +1593,8 @@ intel_dp_compute_config(struct intel_encoder *encoder, int common_rates[DP_MAX_SUPPORTED_RATES] = {}; int common_len; uint8_t link_bw, rate_select; + bool reduce_m_n = drm_dp_has_quirk(&intel_dp->desc, + DP_DPCD_QUIRK_LIMITED_M_N); common_len = intel_dp_common_rates(intel_dp, common_rates); @@ -1722,7 +1724,8 @@ found: intel_link_compute_m_n(bpp, lane_count, adjusted_mode->crtc_clock, pipe_config->port_clock, - &pipe_config->dp_m_n); + &pipe_config->dp_m_n, + reduce_m_n); if (intel_connector->panel.downclock_mode != NULL && dev_priv->drrs.type == SEAMLESS_DRRS_SUPPORT) { @@ -1730,7 +1733,8 @@ found: intel_link_compute_m_n(bpp, lane_count, intel_connector->panel.downclock_mode->clock, pipe_config->port_clock, - &pipe_config->dp_m2_n2); + &pipe_config->dp_m2_n2, + reduce_m_n); } /* |