| Message ID | 1472767699-31211-11-git-send-email-manasi.d.navare@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Thu, 2016-09-01 at 15:08 -0700, Manasi Navare wrote: > Fix the number of tries in channel euqalization link training > sequence > according to DP 1.2 Spec. It returns a boolean depending on channel > equalization pass or failure. > > Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com> > Signed-off-by: Manasi Navare <manasi.d.navare@intel.com> > --- > drivers/gpu/drm/i915/intel_dp_link_training.c | 57 ++++++++++------- > ---------- > drivers/gpu/drm/i915/intel_drv.h | 1 + > 2 files changed, 22 insertions(+), 36 deletions(-) > > diff --git a/drivers/gpu/drm/i915/intel_dp_link_training.c > b/drivers/gpu/drm/i915/intel_dp_link_training.c > index 13a0341..07f0159 100644 > --- a/drivers/gpu/drm/i915/intel_dp_link_training.c > +++ b/drivers/gpu/drm/i915/intel_dp_link_training.c > @@ -240,12 +240,12 @@ static u32 intel_dp_training_pattern(struct > intel_dp *intel_dp) > return training_pattern; > } > > -static void > +static bool > intel_dp_link_training_channel_equalization(struct intel_dp > *intel_dp) > { > - bool channel_eq = false; > - int tries, cr_tries; > + int tries; > u32 training_pattern; > + uint8_t link_status[DP_LINK_STATUS_SIZE]; > > training_pattern = intel_dp_training_pattern(intel_dp); > > @@ -254,20 +254,11 @@ > intel_dp_link_training_channel_equalization(struct intel_dp > *intel_dp) > training_pattern | > DP_LINK_SCRAMBLING_DISABLE)) { > DRM_ERROR("failed to start channel equalization\n"); > - return; > + return false; > } > > - tries = 0; > - cr_tries = 0; > - channel_eq = false; > - for (;;) { > - uint8_t link_status[DP_LINK_STATUS_SIZE]; > - > - if (cr_tries > 5) { > - DRM_ERROR("failed to train DP, aborting\n"); > - intel_dp_dump_link_status(link_status); > - break; > - } > + intel_dp->channel_eq_status = false; > + for (tries = 0; tries < 5; tries++) { > > drm_dp_link_train_channel_eq_delay(intel_dp->dpcd); > if (!intel_dp_get_link_status(intel_dp, > link_status)) { > @@ -278,44 +269,38 @@ > intel_dp_link_training_channel_equalization(struct intel_dp > *intel_dp) > /* Make sure clock is still ok */ > if (!drm_dp_clock_recovery_ok(link_status, > intel_dp->lane_count)) > { > - intel_dp_link_training_clock_recovery(intel_ > dp); > - intel_dp_set_link_train(intel_dp, > - training_pattern | > - DP_LINK_SCRAMBLING_D > ISABLE); > - cr_tries++; > - continue; > + intel_dp_dump_link_status(link_status); > + DRM_DEBUG_KMS("Clock recovery check failed, > cannot " > + "continue channel > equalization\n"); > + break; > } This clock recovery check got me thinking. Do we really need to check if clock recovery is still ok within a loop? Could we move this outside the loop and return early if we have failed in clock recovery? One idea that I have in mind is that we wouldn't need to enter in channel equalization if we have failed with clock recovery earlier. > > if (drm_dp_channel_eq_ok(link_status, > intel_dp->lane_count)) { > - channel_eq = true; > + intel_dp->channel_eq_status = true; > + DRM_DEBUG_KMS("Channel EQ done. DP Training > " > + "successful\n"); > break; > } > > - /* Try 5 times, then try clock recovery if that > fails */ > - if (tries > 5) { > - intel_dp_link_training_clock_recovery(intel_ > dp); > - intel_dp_set_link_train(intel_dp, > - training_pattern | > - DP_LINK_SCRAMBLING_D > ISABLE); > - tries = 0; > - cr_tries++; > - continue; > - } > - > /* Update training set as requested by target */ > intel_get_adjust_train(intel_dp, link_status); > if (!intel_dp_update_link_train(intel_dp)) { > DRM_ERROR("failed to update link > training\n"); > break; > } > - ++tries; > + } > + > + /* Try 5 times, else fail and try at lower BW */ > + if (tries == 5) { > + intel_dp_dump_link_status(link_status); > + DRM_DEBUG_KMS("Channel equalization failed 5 > times\n"); > } > > intel_dp_set_idle_link_train(intel_dp); > > - if (channel_eq) > - DRM_DEBUG_KMS("Channel EQ done. DP Training > successful\n"); > + return intel_dp->channel_eq_status; > + > } > > void intel_dp_stop_link_train(struct intel_dp *intel_dp) > diff --git a/drivers/gpu/drm/i915/intel_drv.h > b/drivers/gpu/drm/i915/intel_drv.h > index efcd80b..e5bc976 100644 > --- a/drivers/gpu/drm/i915/intel_drv.h > +++ b/drivers/gpu/drm/i915/intel_drv.h > @@ -878,6 +878,7 @@ struct intel_dp { > bool link_mst; > bool has_audio; > bool detect_done; > + bool channel_eq_status; > enum hdmi_force_audio force_audio; > bool limited_color_range; > bool color_range_auto;
On Fri, 2016-09-02 at 14:20 +0300, Mika Kahola wrote: > On Thu, 2016-09-01 at 15:08 -0700, Manasi Navare wrote: > > Fix the number of tries in channel euqalization link training > > sequence > > according to DP 1.2 Spec. It returns a boolean depending on channel > > equalization pass or failure. > > > > Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com> > > Signed-off-by: Manasi Navare <manasi.d.navare@intel.com> > > --- > > drivers/gpu/drm/i915/intel_dp_link_training.c | 57 ++++++++++------- > > ---------- > > drivers/gpu/drm/i915/intel_drv.h | 1 + > > 2 files changed, 22 insertions(+), 36 deletions(-) > > > > diff --git a/drivers/gpu/drm/i915/intel_dp_link_training.c > > b/drivers/gpu/drm/i915/intel_dp_link_training.c > > index 13a0341..07f0159 100644 > > --- a/drivers/gpu/drm/i915/intel_dp_link_training.c > > +++ b/drivers/gpu/drm/i915/intel_dp_link_training.c > > @@ -240,12 +240,12 @@ static u32 intel_dp_training_pattern(struct > > intel_dp *intel_dp) > > return training_pattern; > > } > > > > -static void > > +static bool > > intel_dp_link_training_channel_equalization(struct intel_dp > > *intel_dp) > > { > > - bool channel_eq = false; > > - int tries, cr_tries; > > + int tries; > > u32 training_pattern; > > + uint8_t link_status[DP_LINK_STATUS_SIZE]; > > > > training_pattern = intel_dp_training_pattern(intel_dp); > > > > @@ -254,20 +254,11 @@ > > intel_dp_link_training_channel_equalization(struct intel_dp > > *intel_dp) > > training_pattern | > > DP_LINK_SCRAMBLING_DISABLE)) { > > DRM_ERROR("failed to start channel equalization\n"); > > - return; > > + return false; > > } > > > > - tries = 0; > > - cr_tries = 0; > > - channel_eq = false; > > - for (;;) { > > - uint8_t link_status[DP_LINK_STATUS_SIZE]; > > - > > - if (cr_tries > 5) { > > - DRM_ERROR("failed to train DP, aborting\n"); > > - intel_dp_dump_link_status(link_status); > > - break; > > - } > > + intel_dp->channel_eq_status = false; > > + for (tries = 0; tries < 5; tries++) { > > > > drm_dp_link_train_channel_eq_delay(intel_dp->dpcd); > > if (!intel_dp_get_link_status(intel_dp, > > link_status)) { > > @@ -278,44 +269,38 @@ > > intel_dp_link_training_channel_equalization(struct intel_dp > > *intel_dp) > > /* Make sure clock is still ok */ > > if (!drm_dp_clock_recovery_ok(link_status, > > intel_dp->lane_count)) > > { > > - intel_dp_link_training_clock_recovery(intel_ > > dp); > > - intel_dp_set_link_train(intel_dp, > > - training_pattern | > > - DP_LINK_SCRAMBLING_D > > ISABLE); > > - cr_tries++; > > - continue; > > + intel_dp_dump_link_status(link_status); > > + DRM_DEBUG_KMS("Clock recovery check failed, > > cannot " > > + "continue channel > > equalization\n"); > > + break; > > } > This clock recovery check got me thinking. Do we really need to check > if clock recovery is still ok within a loop? Could we move this outside > the loop and return early if we have failed in clock recovery? One idea > that I have in mind is that we wouldn't need to enter in channel > equalization if we have failed with clock recovery earlier. > Looks like we do. This check helps us to break out of the loop for link rate reduction after adjusting drive setting. > > > > if (drm_dp_channel_eq_ok(link_status, > > intel_dp->lane_count)) { > > - channel_eq = true; > > + intel_dp->channel_eq_status = true; > > + DRM_DEBUG_KMS("Channel EQ done. DP Training > > " > > + "successful\n"); > > break; > > } > > > > - /* Try 5 times, then try clock recovery if that > > fails */ > > - if (tries > 5) { > > - intel_dp_link_training_clock_recovery(intel_ > > dp); > > - intel_dp_set_link_train(intel_dp, > > - training_pattern | > > - DP_LINK_SCRAMBLING_D > > ISABLE); > > - tries = 0; > > - cr_tries++; > > - continue; > > - } > > - > > /* Update training set as requested by target */ > > intel_get_adjust_train(intel_dp, link_status); > > if (!intel_dp_update_link_train(intel_dp)) { > > DRM_ERROR("failed to update link > > training\n"); > > break; > > } > > - ++tries; > > + } > > + > > + /* Try 5 times, else fail and try at lower BW */ > > + if (tries == 5) { > > + intel_dp_dump_link_status(link_status); > > + DRM_DEBUG_KMS("Channel equalization failed 5 > > times\n"); > > } > > > > intel_dp_set_idle_link_train(intel_dp); > > > > - if (channel_eq) > > - DRM_DEBUG_KMS("Channel EQ done. DP Training > > successful\n"); > > + return intel_dp->channel_eq_status; > > + > > } > > > > void intel_dp_stop_link_train(struct intel_dp *intel_dp) > > diff --git a/drivers/gpu/drm/i915/intel_drv.h > > b/drivers/gpu/drm/i915/intel_drv.h > > index efcd80b..e5bc976 100644 > > --- a/drivers/gpu/drm/i915/intel_drv.h > > +++ b/drivers/gpu/drm/i915/intel_drv.h > > @@ -878,6 +878,7 @@ struct intel_dp { > > bool link_mst; > > bool has_audio; > > bool detect_done; > > + bool channel_eq_status; > > enum hdmi_force_audio force_audio; > > bool limited_color_range; > > bool color_range_auto;
Reviewed-by: Mika Kahola <mika.kahola@intel.com> On Fri, 2016-09-02 at 22:05 +0300, Pandiyan, Dhinakaran wrote: > On Fri, 2016-09-02 at 14:20 +0300, Mika Kahola wrote: > > > > On Thu, 2016-09-01 at 15:08 -0700, Manasi Navare wrote: > > > > > > Fix the number of tries in channel euqalization link training > > > sequence > > > according to DP 1.2 Spec. It returns a boolean depending on > > > channel > > > equalization pass or failure. > > > > > > Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com > > > > > > > Signed-off-by: Manasi Navare <manasi.d.navare@intel.com> > > > --- > > > drivers/gpu/drm/i915/intel_dp_link_training.c | 57 ++++++++++--- > > > ---- > > > ---------- > > > drivers/gpu/drm/i915/intel_drv.h | 1 + > > > 2 files changed, 22 insertions(+), 36 deletions(-) > > > > > > diff --git a/drivers/gpu/drm/i915/intel_dp_link_training.c > > > b/drivers/gpu/drm/i915/intel_dp_link_training.c > > > index 13a0341..07f0159 100644 > > > --- a/drivers/gpu/drm/i915/intel_dp_link_training.c > > > +++ b/drivers/gpu/drm/i915/intel_dp_link_training.c > > > @@ -240,12 +240,12 @@ static u32 intel_dp_training_pattern(struct > > > intel_dp *intel_dp) > > > return training_pattern; > > > } > > > > > > -static void > > > +static bool > > > intel_dp_link_training_channel_equalization(struct intel_dp > > > *intel_dp) > > > { > > > - bool channel_eq = false; > > > - int tries, cr_tries; > > > + int tries; > > > u32 training_pattern; > > > + uint8_t link_status[DP_LINK_STATUS_SIZE]; > > > > > > training_pattern = intel_dp_training_pattern(intel_dp); > > > > > > @@ -254,20 +254,11 @@ > > > intel_dp_link_training_channel_equalization(struct intel_dp > > > *intel_dp) > > > training_pattern | > > > DP_LINK_SCRAMBLING_DISABLE) > > > ) { > > > DRM_ERROR("failed to start channel > > > equalization\n"); > > > - return; > > > + return false; > > > } > > > > > > - tries = 0; > > > - cr_tries = 0; > > > - channel_eq = false; > > > - for (;;) { > > > - uint8_t link_status[DP_LINK_STATUS_SIZE]; > > > - > > > - if (cr_tries > 5) { > > > - DRM_ERROR("failed to train DP, > > > aborting\n"); > > > - intel_dp_dump_link_status(link_status); > > > - break; > > > - } > > > + intel_dp->channel_eq_status = false; > > > + for (tries = 0; tries < 5; tries++) { > > > > > > drm_dp_link_train_channel_eq_delay(intel_dp- > > > >dpcd); > > > if (!intel_dp_get_link_status(intel_dp, > > > link_status)) { > > > @@ -278,44 +269,38 @@ > > > intel_dp_link_training_channel_equalization(struct intel_dp > > > *intel_dp) > > > /* Make sure clock is still ok */ > > > if (!drm_dp_clock_recovery_ok(link_status, > > > intel_dp- > > > >lane_count)) > > > { > > > - intel_dp_link_training_clock_recovery(in > > > tel_ > > > dp); > > > - intel_dp_set_link_train(intel_dp, > > > - training_pattern > > > | > > > - DP_LINK_SCRAMBLI > > > NG_D > > > ISABLE); > > > - cr_tries++; > > > - continue; > > > + intel_dp_dump_link_status(link_status); > > > + DRM_DEBUG_KMS("Clock recovery check > > > failed, > > > cannot " > > > + "continue channel > > > equalization\n"); > > > + break; > > > } > > This clock recovery check got me thinking. Do we really need to > > check > > if clock recovery is still ok within a loop? Could we move this > > outside > > the loop and return early if we have failed in clock recovery? One > > idea > > that I have in mind is that we wouldn't need to enter in channel > > equalization if we have failed with clock recovery earlier. > > > Looks like we do. This check helps us to break out of the loop for > link > rate reduction after adjusting drive setting. You're right we do that. > > > > > > > > > > > > > if (drm_dp_channel_eq_ok(link_status, > > > intel_dp->lane_count)) > > > { > > > - channel_eq = true; > > > + intel_dp->channel_eq_status = true; > > > + DRM_DEBUG_KMS("Channel EQ done. DP > > > Training > > > " > > > + "successful\n"); > > > break; > > > } > > > > > > - /* Try 5 times, then try clock recovery if that > > > fails */ > > > - if (tries > 5) { > > > - intel_dp_link_training_clock_recovery(in > > > tel_ > > > dp); > > > - intel_dp_set_link_train(intel_dp, > > > - training_pattern > > > | > > > - DP_LINK_SCRAMBLI > > > NG_D > > > ISABLE); > > > - tries = 0; > > > - cr_tries++; > > > - continue; > > > - } > > > - > > > /* Update training set as requested by target */ > > > intel_get_adjust_train(intel_dp, link_status); > > > if (!intel_dp_update_link_train(intel_dp)) { > > > DRM_ERROR("failed to update link > > > training\n"); > > > break; > > > } > > > - ++tries; > > > + } > > > + > > > + /* Try 5 times, else fail and try at lower BW */ > > > + if (tries == 5) { > > > + intel_dp_dump_link_status(link_status); > > > + DRM_DEBUG_KMS("Channel equalization failed 5 > > > times\n"); > > > } > > > > > > intel_dp_set_idle_link_train(intel_dp); > > > > > > - if (channel_eq) > > > - DRM_DEBUG_KMS("Channel EQ done. DP Training > > > successful\n"); > > > + return intel_dp->channel_eq_status; > > > + > > > } > > > > > > void intel_dp_stop_link_train(struct intel_dp *intel_dp) > > > diff --git a/drivers/gpu/drm/i915/intel_drv.h > > > b/drivers/gpu/drm/i915/intel_drv.h > > > index efcd80b..e5bc976 100644 > > > --- a/drivers/gpu/drm/i915/intel_drv.h > > > +++ b/drivers/gpu/drm/i915/intel_drv.h > > > @@ -878,6 +878,7 @@ struct intel_dp { > > > bool link_mst; > > > bool has_audio; > > > bool detect_done; > > > + bool channel_eq_status; > > > enum hdmi_force_audio force_audio; > > > bool limited_color_range; > > > bool color_range_auto;
Patches 1 to 10 merged on dinq last week. Thanks for patches and reviews and sorry for the delayed update. On Wed, Sep 7, 2016 at 12:50 AM, Mika Kahola <mika.kahola@intel.com> wrote: > Reviewed-by: Mika Kahola <mika.kahola@intel.com> > > On Fri, 2016-09-02 at 22:05 +0300, Pandiyan, Dhinakaran wrote: >> On Fri, 2016-09-02 at 14:20 +0300, Mika Kahola wrote: >> > >> > On Thu, 2016-09-01 at 15:08 -0700, Manasi Navare wrote: >> > > >> > > Fix the number of tries in channel euqalization link training >> > > sequence >> > > according to DP 1.2 Spec. It returns a boolean depending on >> > > channel >> > > equalization pass or failure. >> > > >> > > Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com >> > > > >> > > Signed-off-by: Manasi Navare <manasi.d.navare@intel.com> >> > > --- >> > > drivers/gpu/drm/i915/intel_dp_link_training.c | 57 ++++++++++--- >> > > ---- >> > > ---------- >> > > drivers/gpu/drm/i915/intel_drv.h | 1 + >> > > 2 files changed, 22 insertions(+), 36 deletions(-) >> > > >> > > diff --git a/drivers/gpu/drm/i915/intel_dp_link_training.c >> > > b/drivers/gpu/drm/i915/intel_dp_link_training.c >> > > index 13a0341..07f0159 100644 >> > > --- a/drivers/gpu/drm/i915/intel_dp_link_training.c >> > > +++ b/drivers/gpu/drm/i915/intel_dp_link_training.c >> > > @@ -240,12 +240,12 @@ static u32 intel_dp_training_pattern(struct >> > > intel_dp *intel_dp) >> > > return training_pattern; >> > > } >> > > >> > > -static void >> > > +static bool >> > > intel_dp_link_training_channel_equalization(struct intel_dp >> > > *intel_dp) >> > > { >> > > - bool channel_eq = false; >> > > - int tries, cr_tries; >> > > + int tries; >> > > u32 training_pattern; >> > > + uint8_t link_status[DP_LINK_STATUS_SIZE]; >> > > >> > > training_pattern = intel_dp_training_pattern(intel_dp); >> > > >> > > @@ -254,20 +254,11 @@ >> > > intel_dp_link_training_channel_equalization(struct intel_dp >> > > *intel_dp) >> > > training_pattern | >> > > DP_LINK_SCRAMBLING_DISABLE) >> > > ) { >> > > DRM_ERROR("failed to start channel >> > > equalization\n"); >> > > - return; >> > > + return false; >> > > } >> > > >> > > - tries = 0; >> > > - cr_tries = 0; >> > > - channel_eq = false; >> > > - for (;;) { >> > > - uint8_t link_status[DP_LINK_STATUS_SIZE]; >> > > - >> > > - if (cr_tries > 5) { >> > > - DRM_ERROR("failed to train DP, >> > > aborting\n"); >> > > - intel_dp_dump_link_status(link_status); >> > > - break; >> > > - } >> > > + intel_dp->channel_eq_status = false; >> > > + for (tries = 0; tries < 5; tries++) { >> > > >> > > drm_dp_link_train_channel_eq_delay(intel_dp- >> > > >dpcd); >> > > if (!intel_dp_get_link_status(intel_dp, >> > > link_status)) { >> > > @@ -278,44 +269,38 @@ >> > > intel_dp_link_training_channel_equalization(struct intel_dp >> > > *intel_dp) >> > > /* Make sure clock is still ok */ >> > > if (!drm_dp_clock_recovery_ok(link_status, >> > > intel_dp- >> > > >lane_count)) >> > > { >> > > - intel_dp_link_training_clock_recovery(in >> > > tel_ >> > > dp); >> > > - intel_dp_set_link_train(intel_dp, >> > > - training_pattern >> > > | >> > > - DP_LINK_SCRAMBLI >> > > NG_D >> > > ISABLE); >> > > - cr_tries++; >> > > - continue; >> > > + intel_dp_dump_link_status(link_status); >> > > + DRM_DEBUG_KMS("Clock recovery check >> > > failed, >> > > cannot " >> > > + "continue channel >> > > equalization\n"); >> > > + break; >> > > } >> > This clock recovery check got me thinking. Do we really need to >> > check >> > if clock recovery is still ok within a loop? Could we move this >> > outside >> > the loop and return early if we have failed in clock recovery? One >> > idea >> > that I have in mind is that we wouldn't need to enter in channel >> > equalization if we have failed with clock recovery earlier. >> > >> Looks like we do. This check helps us to break out of the loop for >> link >> rate reduction after adjusting drive setting. > You're right we do that. >> >> >> > >> > > >> > > >> > > if (drm_dp_channel_eq_ok(link_status, >> > > intel_dp->lane_count)) >> > > { >> > > - channel_eq = true; >> > > + intel_dp->channel_eq_status = true; >> > > + DRM_DEBUG_KMS("Channel EQ done. DP >> > > Training >> > > " >> > > + "successful\n"); >> > > break; >> > > } >> > > >> > > - /* Try 5 times, then try clock recovery if that >> > > fails */ >> > > - if (tries > 5) { >> > > - intel_dp_link_training_clock_recovery(in >> > > tel_ >> > > dp); >> > > - intel_dp_set_link_train(intel_dp, >> > > - training_pattern >> > > | >> > > - DP_LINK_SCRAMBLI >> > > NG_D >> > > ISABLE); >> > > - tries = 0; >> > > - cr_tries++; >> > > - continue; >> > > - } >> > > - >> > > /* Update training set as requested by target */ >> > > intel_get_adjust_train(intel_dp, link_status); >> > > if (!intel_dp_update_link_train(intel_dp)) { >> > > DRM_ERROR("failed to update link >> > > training\n"); >> > > break; >> > > } >> > > - ++tries; >> > > + } >> > > + >> > > + /* Try 5 times, else fail and try at lower BW */ >> > > + if (tries == 5) { >> > > + intel_dp_dump_link_status(link_status); >> > > + DRM_DEBUG_KMS("Channel equalization failed 5 >> > > times\n"); >> > > } >> > > >> > > intel_dp_set_idle_link_train(intel_dp); >> > > >> > > - if (channel_eq) >> > > - DRM_DEBUG_KMS("Channel EQ done. DP Training >> > > successful\n"); >> > > + return intel_dp->channel_eq_status; >> > > + >> > > } >> > > >> > > void intel_dp_stop_link_train(struct intel_dp *intel_dp) >> > > diff --git a/drivers/gpu/drm/i915/intel_drv.h >> > > b/drivers/gpu/drm/i915/intel_drv.h >> > > index efcd80b..e5bc976 100644 >> > > --- a/drivers/gpu/drm/i915/intel_drv.h >> > > +++ b/drivers/gpu/drm/i915/intel_drv.h >> > > @@ -878,6 +878,7 @@ struct intel_dp { >> > > bool link_mst; >> > > bool has_audio; >> > > bool detect_done; >> > > + bool channel_eq_status; >> > > enum hdmi_force_audio force_audio; >> > > bool limited_color_range; >> > > bool color_range_auto; > -- > Mika Kahola - Intel OTC > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/intel-gfx
diff --git a/drivers/gpu/drm/i915/intel_dp_link_training.c b/drivers/gpu/drm/i915/intel_dp_link_training.c index 13a0341..07f0159 100644 --- a/drivers/gpu/drm/i915/intel_dp_link_training.c +++ b/drivers/gpu/drm/i915/intel_dp_link_training.c @@ -240,12 +240,12 @@ static u32 intel_dp_training_pattern(struct intel_dp *intel_dp) return training_pattern; } -static void +static bool intel_dp_link_training_channel_equalization(struct intel_dp *intel_dp) { - bool channel_eq = false; - int tries, cr_tries; + int tries; u32 training_pattern; + uint8_t link_status[DP_LINK_STATUS_SIZE]; training_pattern = intel_dp_training_pattern(intel_dp); @@ -254,20 +254,11 @@ intel_dp_link_training_channel_equalization(struct intel_dp *intel_dp) training_pattern | DP_LINK_SCRAMBLING_DISABLE)) { DRM_ERROR("failed to start channel equalization\n"); - return; + return false; } - tries = 0; - cr_tries = 0; - channel_eq = false; - for (;;) { - uint8_t link_status[DP_LINK_STATUS_SIZE]; - - if (cr_tries > 5) { - DRM_ERROR("failed to train DP, aborting\n"); - intel_dp_dump_link_status(link_status); - break; - } + intel_dp->channel_eq_status = false; + for (tries = 0; tries < 5; tries++) { drm_dp_link_train_channel_eq_delay(intel_dp->dpcd); if (!intel_dp_get_link_status(intel_dp, link_status)) { @@ -278,44 +269,38 @@ intel_dp_link_training_channel_equalization(struct intel_dp *intel_dp) /* Make sure clock is still ok */ if (!drm_dp_clock_recovery_ok(link_status, intel_dp->lane_count)) { - intel_dp_link_training_clock_recovery(intel_dp); - intel_dp_set_link_train(intel_dp, - training_pattern | - DP_LINK_SCRAMBLING_DISABLE); - cr_tries++; - continue; + intel_dp_dump_link_status(link_status); + DRM_DEBUG_KMS("Clock recovery check failed, cannot " + "continue channel equalization\n"); + break; } if (drm_dp_channel_eq_ok(link_status, intel_dp->lane_count)) { - channel_eq = true; + intel_dp->channel_eq_status = true; + DRM_DEBUG_KMS("Channel EQ done. DP Training " + "successful\n"); break; } - /* Try 5 times, then try clock recovery if that fails */ - if (tries > 5) { - intel_dp_link_training_clock_recovery(intel_dp); - intel_dp_set_link_train(intel_dp, - training_pattern | - DP_LINK_SCRAMBLING_DISABLE); - tries = 0; - cr_tries++; - continue; - } - /* Update training set as requested by target */ intel_get_adjust_train(intel_dp, link_status); if (!intel_dp_update_link_train(intel_dp)) { DRM_ERROR("failed to update link training\n"); break; } - ++tries; + } + + /* Try 5 times, else fail and try at lower BW */ + if (tries == 5) { + intel_dp_dump_link_status(link_status); + DRM_DEBUG_KMS("Channel equalization failed 5 times\n"); } intel_dp_set_idle_link_train(intel_dp); - if (channel_eq) - DRM_DEBUG_KMS("Channel EQ done. DP Training successful\n"); + return intel_dp->channel_eq_status; + } void intel_dp_stop_link_train(struct intel_dp *intel_dp) diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h index efcd80b..e5bc976 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -878,6 +878,7 @@ struct intel_dp { bool link_mst; bool has_audio; bool detect_done; + bool channel_eq_status; enum hdmi_force_audio force_audio; bool limited_color_range; bool color_range_auto;