| Message ID | 1430288260-23718-2-git-send-email-mika.kahola@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Reviewed-by: Sivakumar Thulasimani <sivakumar.thulasimani@intel.com> On 4/29/2015 11:47 AM, Mika Kahola wrote: > This is a first of series patches that optimize DP link > training. The first patch is for eDP only where we reuse > the previously trained link training values from cache > i.e. voltage swing and pre-emphasis levels. > > In case we are not able to train the link by reusing > the known values, the link training parameters are set > to zero and training is restarted. > > V2: > - flag that indicates if DP link is trained and valid > renamed from 'link_trained' to 'train_set_valid' > - removed routine 'intel_dp_reuse_link_train' > > V3: > - rebased against the latest drm-intel-nightly > > V4: > - removed HPD long pulse handling for eDP case to clear the > flag that indicates to reuse the current link training > parameters. (based on Sivakumar's comment) > > Signed-off-by: Mika Kahola <mika.kahola@intel.com> > --- > drivers/gpu/drm/i915/intel_dp.c | 27 ++++++++++++++++++++++++--- > drivers/gpu/drm/i915/intel_drv.h | 1 + > 2 files changed, 25 insertions(+), 3 deletions(-) > > diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c > index 937ba31..e0b35cb 100644 > --- a/drivers/gpu/drm/i915/intel_dp.c > +++ b/drivers/gpu/drm/i915/intel_dp.c > @@ -3547,7 +3547,8 @@ static bool > intel_dp_reset_link_train(struct intel_dp *intel_dp, uint32_t *DP, > uint8_t dp_train_pat) > { > - memset(intel_dp->train_set, 0, sizeof(intel_dp->train_set)); > + if (!intel_dp->train_set_valid) > + memset(intel_dp->train_set, 0, sizeof(intel_dp->train_set)); > intel_dp_set_signal_levels(intel_dp, DP); > return intel_dp_set_link_train(intel_dp, DP, dp_train_pat); > } > @@ -3660,6 +3661,23 @@ intel_dp_start_link_train(struct intel_dp *intel_dp) > break; > } > > + /* > + * if we used previously trained voltage and pre-emphasis values > + * and we don't get clock recovery, reset link training values > + */ > + if (intel_dp->train_set_valid) { > + DRM_DEBUG_KMS("clock recovery not ok, reset"); > + /* clear the flag as we are not reusing train set */ > + intel_dp->train_set_valid = false; > + if (!intel_dp_reset_link_train(intel_dp, &DP, > + DP_TRAINING_PATTERN_1 | > + DP_LINK_SCRAMBLING_DISABLE)) { > + DRM_ERROR("failed to enable link training\n"); > + return; > + } > + continue; > + } > + > /* Check to see if we've tried the max voltage */ > for (i = 0; i < intel_dp->lane_count; i++) > if ((intel_dp->train_set[i] & DP_TRAIN_MAX_SWING_REACHED) == 0) > @@ -3737,6 +3755,7 @@ intel_dp_complete_link_train(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->train_set_valid = false; > intel_dp_start_link_train(intel_dp); > intel_dp_set_link_train(intel_dp, &DP, > training_pattern | > @@ -3752,6 +3771,7 @@ intel_dp_complete_link_train(struct intel_dp *intel_dp) > > /* Try 5 times, then try clock recovery if that fails */ > if (tries > 5) { > + intel_dp->train_set_valid = false; > intel_dp_start_link_train(intel_dp); > intel_dp_set_link_train(intel_dp, &DP, > training_pattern | > @@ -3773,9 +3793,10 @@ intel_dp_complete_link_train(struct intel_dp *intel_dp) > > intel_dp->DP = DP; > > - if (channel_eq) > + if (channel_eq) { > + intel_dp->train_set_valid = is_edp(intel_dp); > DRM_DEBUG_KMS("Channel EQ done. DP Training successful\n"); > - > + } > } > > 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 43fe003..94197bd 100644 > --- a/drivers/gpu/drm/i915/intel_drv.h > +++ b/drivers/gpu/drm/i915/intel_drv.h > @@ -736,6 +736,7 @@ struct intel_dp { > bool has_aux_irq, > int send_bytes, > uint32_t aux_clock_divider); > + bool train_set_valid; > > /* Displayport compliance testing */ > unsigned long compliance_test_type;
On Wed, Apr 29, 2015 at 11:56:41AM +0530, Sivakumar Thulasimani wrote: > Reviewed-by: Sivakumar Thulasimani <sivakumar.thulasimani@intel.com> > > On 4/29/2015 11:47 AM, Mika Kahola wrote: > >This is a first of series patches that optimize DP link > >training. The first patch is for eDP only where we reuse > >the previously trained link training values from cache > >i.e. voltage swing and pre-emphasis levels. > > > >In case we are not able to train the link by reusing > >the known values, the link training parameters are set > >to zero and training is restarted. > > > >V2: > >- flag that indicates if DP link is trained and valid > > renamed from 'link_trained' to 'train_set_valid' > >- removed routine 'intel_dp_reuse_link_train' > > > >V3: > >- rebased against the latest drm-intel-nightly > > > >V4: > >- removed HPD long pulse handling for eDP case to clear the > > flag that indicates to reuse the current link training > > parameters. (based on Sivakumar's comment) > > > >Signed-off-by: Mika Kahola <mika.kahola@intel.com> Both merged, with an s/DP/eDP/ on this one to make the different scope of the 2 patches clear. Two patches with the same summary is confusing ;-) Thanks, Daniel > >--- > > drivers/gpu/drm/i915/intel_dp.c | 27 ++++++++++++++++++++++++--- > > drivers/gpu/drm/i915/intel_drv.h | 1 + > > 2 files changed, 25 insertions(+), 3 deletions(-) > > > >diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c > >index 937ba31..e0b35cb 100644 > >--- a/drivers/gpu/drm/i915/intel_dp.c > >+++ b/drivers/gpu/drm/i915/intel_dp.c > >@@ -3547,7 +3547,8 @@ static bool > > intel_dp_reset_link_train(struct intel_dp *intel_dp, uint32_t *DP, > > uint8_t dp_train_pat) > > { > >- memset(intel_dp->train_set, 0, sizeof(intel_dp->train_set)); > >+ if (!intel_dp->train_set_valid) > >+ memset(intel_dp->train_set, 0, sizeof(intel_dp->train_set)); > > intel_dp_set_signal_levels(intel_dp, DP); > > return intel_dp_set_link_train(intel_dp, DP, dp_train_pat); > > } > >@@ -3660,6 +3661,23 @@ intel_dp_start_link_train(struct intel_dp *intel_dp) > > break; > > } > >+ /* > >+ * if we used previously trained voltage and pre-emphasis values > >+ * and we don't get clock recovery, reset link training values > >+ */ > >+ if (intel_dp->train_set_valid) { > >+ DRM_DEBUG_KMS("clock recovery not ok, reset"); > >+ /* clear the flag as we are not reusing train set */ > >+ intel_dp->train_set_valid = false; > >+ if (!intel_dp_reset_link_train(intel_dp, &DP, > >+ DP_TRAINING_PATTERN_1 | > >+ DP_LINK_SCRAMBLING_DISABLE)) { > >+ DRM_ERROR("failed to enable link training\n"); > >+ return; > >+ } > >+ continue; > >+ } > >+ > > /* Check to see if we've tried the max voltage */ > > for (i = 0; i < intel_dp->lane_count; i++) > > if ((intel_dp->train_set[i] & DP_TRAIN_MAX_SWING_REACHED) == 0) > >@@ -3737,6 +3755,7 @@ intel_dp_complete_link_train(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->train_set_valid = false; > > intel_dp_start_link_train(intel_dp); > > intel_dp_set_link_train(intel_dp, &DP, > > training_pattern | > >@@ -3752,6 +3771,7 @@ intel_dp_complete_link_train(struct intel_dp *intel_dp) > > /* Try 5 times, then try clock recovery if that fails */ > > if (tries > 5) { > >+ intel_dp->train_set_valid = false; > > intel_dp_start_link_train(intel_dp); > > intel_dp_set_link_train(intel_dp, &DP, > > training_pattern | > >@@ -3773,9 +3793,10 @@ intel_dp_complete_link_train(struct intel_dp *intel_dp) > > intel_dp->DP = DP; > >- if (channel_eq) > >+ if (channel_eq) { > >+ intel_dp->train_set_valid = is_edp(intel_dp); > > DRM_DEBUG_KMS("Channel EQ done. DP Training successful\n"); > >- > >+ } > > } > > 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 43fe003..94197bd 100644 > >--- a/drivers/gpu/drm/i915/intel_drv.h > >+++ b/drivers/gpu/drm/i915/intel_drv.h > >@@ -736,6 +736,7 @@ struct intel_dp { > > bool has_aux_irq, > > int send_bytes, > > uint32_t aux_clock_divider); > >+ bool train_set_valid; > > /* Displayport compliance testing */ > > unsigned long compliance_test_type; > > -- > regards, > Sivakumar > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/intel-gfx
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 937ba31..e0b35cb 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -3547,7 +3547,8 @@ static bool intel_dp_reset_link_train(struct intel_dp *intel_dp, uint32_t *DP, uint8_t dp_train_pat) { - memset(intel_dp->train_set, 0, sizeof(intel_dp->train_set)); + if (!intel_dp->train_set_valid) + memset(intel_dp->train_set, 0, sizeof(intel_dp->train_set)); intel_dp_set_signal_levels(intel_dp, DP); return intel_dp_set_link_train(intel_dp, DP, dp_train_pat); } @@ -3660,6 +3661,23 @@ intel_dp_start_link_train(struct intel_dp *intel_dp) break; } + /* + * if we used previously trained voltage and pre-emphasis values + * and we don't get clock recovery, reset link training values + */ + if (intel_dp->train_set_valid) { + DRM_DEBUG_KMS("clock recovery not ok, reset"); + /* clear the flag as we are not reusing train set */ + intel_dp->train_set_valid = false; + if (!intel_dp_reset_link_train(intel_dp, &DP, + DP_TRAINING_PATTERN_1 | + DP_LINK_SCRAMBLING_DISABLE)) { + DRM_ERROR("failed to enable link training\n"); + return; + } + continue; + } + /* Check to see if we've tried the max voltage */ for (i = 0; i < intel_dp->lane_count; i++) if ((intel_dp->train_set[i] & DP_TRAIN_MAX_SWING_REACHED) == 0) @@ -3737,6 +3755,7 @@ intel_dp_complete_link_train(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->train_set_valid = false; intel_dp_start_link_train(intel_dp); intel_dp_set_link_train(intel_dp, &DP, training_pattern | @@ -3752,6 +3771,7 @@ intel_dp_complete_link_train(struct intel_dp *intel_dp) /* Try 5 times, then try clock recovery if that fails */ if (tries > 5) { + intel_dp->train_set_valid = false; intel_dp_start_link_train(intel_dp); intel_dp_set_link_train(intel_dp, &DP, training_pattern | @@ -3773,9 +3793,10 @@ intel_dp_complete_link_train(struct intel_dp *intel_dp) intel_dp->DP = DP; - if (channel_eq) + if (channel_eq) { + intel_dp->train_set_valid = is_edp(intel_dp); DRM_DEBUG_KMS("Channel EQ done. DP Training successful\n"); - + } } 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 43fe003..94197bd 100644 --- a/drivers/gpu/drm/i915/intel_drv.h +++ b/drivers/gpu/drm/i915/intel_drv.h @@ -736,6 +736,7 @@ struct intel_dp { bool has_aux_irq, int send_bytes, uint32_t aux_clock_divider); + bool train_set_valid; /* Displayport compliance testing */ unsigned long compliance_test_type;
This is a first of series patches that optimize DP link training. The first patch is for eDP only where we reuse the previously trained link training values from cache i.e. voltage swing and pre-emphasis levels. In case we are not able to train the link by reusing the known values, the link training parameters are set to zero and training is restarted. V2: - flag that indicates if DP link is trained and valid renamed from 'link_trained' to 'train_set_valid' - removed routine 'intel_dp_reuse_link_train' V3: - rebased against the latest drm-intel-nightly V4: - removed HPD long pulse handling for eDP case to clear the flag that indicates to reuse the current link training parameters. (based on Sivakumar's comment) Signed-off-by: Mika Kahola <mika.kahola@intel.com> --- drivers/gpu/drm/i915/intel_dp.c | 27 ++++++++++++++++++++++++--- drivers/gpu/drm/i915/intel_drv.h | 1 + 2 files changed, 25 insertions(+), 3 deletions(-)