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authorJani Nikula <jani.nikula@intel.com>2017-05-18 14:10:25 +0300
committerJani Nikula <jani.nikula@intel.com>2017-05-29 13:43:47 +0300
commitb31e85eda38c58cae986162ae2c462b53b0a2065 (patch)
tree5f7c60ad4e74c0d7c53d089b9f712ae6bd8d63f4 /drivers/gpu/drm/i915/intel_dp.c
parent76fa998acd86b6b40d0217e12af39c2406bdcd2b (diff)
downloadop-kernel-dev-b31e85eda38c58cae986162ae2c462b53b0a2065.zip
op-kernel-dev-b31e85eda38c58cae986162ae2c462b53b0a2065.tar.gz
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.c8
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 5ce45d9..fc691b8 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);
}
/*
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