diff mbox

drm/i915: Kill sink_crc for good

Message ID 20180705192528.30515-1-rodrigo.vivi@intel.com (mailing list archive)
State New, archived
Headers show

Commit Message

Rodrigo Vivi July 5, 2018, 7:25 p.m. UTC
It was originally introduced following the VESA spec in order to validate PSR.

However we found so many issues around sink_crc that instead of helping PSR
development it only brought another layer of trouble to the table.

So, sink_crc has been a black whole for us in question of time, effort and hope.

First of the problems is that HW statement is clear: "Do not attempt to use
aux communication with PSR enabled". So the main reason behind sink_crc is
already compromised.

For a while we had hope on the aux-mutex could workaround this problem on SKL+
platforms, but that mutex was not reliable, not tested,
and we shouldn't use according to HW engineers.

Also, nor source, nor sink designed and implemented the sink_crc to be used like
we are trying to use here.

Well, the sink side of things is also apparently not prepared for this
case. Each panel that we tried seemed to have a different behavior with same
code and same source.

So, for all the time we lost on trying to ducktape all these different issues
I believe it is now time to move PSR to a more reliable validation.
Maybe not a perfect one as we dreamed for this sink_crc, but at least more
reliable.

Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
---
 drivers/gpu/drm/i915/i915_debugfs.c |  81 ------------------
 drivers/gpu/drm/i915/intel_dp.c     | 123 ----------------------------
 drivers/gpu/drm/i915/intel_drv.h    |   2 -
 3 files changed, 206 deletions(-)

Comments

Dhinakaran Pandiyan July 5, 2018, 9:11 p.m. UTC | #1
On Thursday, July 5, 2018 12:25:28 PM PDT Rodrigo Vivi wrote:
> It was originally introduced following the VESA spec in order to validate
> PSR.
> 
> However we found so many issues around sink_crc that instead of helping PSR
> development it only brought another layer of trouble to the table.
> 
> So, sink_crc has been a black whole for us in question of time, effort and
> hope.
> 
> First of the problems is that HW statement is clear: "Do not attempt to use
> aux communication with PSR enabled". So the main reason behind sink_crc is
> already compromised.
> 
> For a while we had hope on the aux-mutex could workaround this problem on
> SKL+ platforms, but that mutex was not reliable, not tested,
> and we shouldn't use according to HW engineers.
> 
> Also, nor source, nor sink designed and implemented the sink_crc to be used
> like we are trying to use here.
> 
> Well, the sink side of things is also apparently not prepared for this
> case. Each panel that we tried seemed to have a different behavior with same
> code and same source.
> 
> So, for all the time we lost on trying to ducktape all these different
> issues I believe it is now time to move PSR to a more reliable validation.
> Maybe not a perfect one as we dreamed for this sink_crc, but at least more
> reliable.
> 
Good riddance.
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>

> Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
> Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
> ---
>  drivers/gpu/drm/i915/i915_debugfs.c |  81 ------------------
>  drivers/gpu/drm/i915/intel_dp.c     | 123 ----------------------------
>  drivers/gpu/drm/i915/intel_drv.h    |   2 -
>  3 files changed, 206 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_debugfs.c
> b/drivers/gpu/drm/i915/i915_debugfs.c index f6142d78ede4..e8fa106a3655
> 100644
> --- a/drivers/gpu/drm/i915/i915_debugfs.c
> +++ b/drivers/gpu/drm/i915/i915_debugfs.c
> @@ -2761,86 +2761,6 @@ DEFINE_SIMPLE_ATTRIBUTE(i915_edp_psr_debug_fops,
>  			i915_edp_psr_debug_get, i915_edp_psr_debug_set,
>  			"%llu\n");
> 
> -static int i915_sink_crc(struct seq_file *m, void *data)
> -{
> -	struct drm_i915_private *dev_priv = node_to_i915(m->private);
> -	struct drm_device *dev = &dev_priv->drm;
> -	struct intel_connector *connector;
> -	struct drm_connector_list_iter conn_iter;
> -	struct intel_dp *intel_dp = NULL;
> -	struct drm_modeset_acquire_ctx ctx;
> -	int ret;
> -	u8 crc[6];
> -
> -	drm_modeset_acquire_init(&ctx, DRM_MODESET_ACQUIRE_INTERRUPTIBLE);
> -
> -	drm_connector_list_iter_begin(dev, &conn_iter);
> -
> -	for_each_intel_connector_iter(connector, &conn_iter) {
> -		struct drm_crtc *crtc;
> -		struct drm_connector_state *state;
> -		struct intel_crtc_state *crtc_state;
> -
> -		if (connector->base.connector_type != DRM_MODE_CONNECTOR_eDP)
> -			continue;
> -
> -retry:
> -		ret = drm_modeset_lock(&dev->mode_config.connection_mutex, &ctx);
> -		if (ret)
> -			goto err;
> -
> -		state = connector->base.state;
> -		if (!state->best_encoder)
> -			continue;
> -
> -		crtc = state->crtc;
> -		ret = drm_modeset_lock(&crtc->mutex, &ctx);
> -		if (ret)
> -			goto err;
> -
> -		crtc_state = to_intel_crtc_state(crtc->state);
> -		if (!crtc_state->base.active)
> -			continue;
> -
> -		/*
> -		 * We need to wait for all crtc updates to complete, to make
> -		 * sure any pending modesets and plane updates are completed.
> -		 */
> -		if (crtc_state->base.commit) {
> -			ret =
> wait_for_completion_interruptible(&crtc_state->base.commit->hw_done); -
> -			if (ret)
> -				goto err;
> -		}
> -
> -		intel_dp = enc_to_intel_dp(state->best_encoder);
> -
> -		ret = intel_dp_sink_crc(intel_dp, crtc_state, crc);
> -		if (ret)
> -			goto err;
> -
> -		seq_printf(m, "%02x%02x%02x%02x%02x%02x\n",
> -			   crc[0], crc[1], crc[2],
> -			   crc[3], crc[4], crc[5]);
> -		goto out;
> -
> -err:
> -		if (ret == -EDEADLK) {
> -			ret = drm_modeset_backoff(&ctx);
> -			if (!ret)
> -				goto retry;
> -		}
> -		goto out;
> -	}
> -	ret = -ENODEV;
> -out:
> -	drm_connector_list_iter_end(&conn_iter);
> -	drm_modeset_drop_locks(&ctx);
> -	drm_modeset_acquire_fini(&ctx);
> -
> -	return ret;
> -}
> -
>  static int i915_energy_uJ(struct seq_file *m, void *data)
>  {
>  	struct drm_i915_private *dev_priv = node_to_i915(m->private);
> @@ -4784,7 +4704,6 @@ static const struct drm_info_list i915_debugfs_list[]
> = { {"i915_ppgtt_info", i915_ppgtt_info, 0},
>  	{"i915_llc", i915_llc, 0},
>  	{"i915_edp_psr_status", i915_edp_psr_status, 0},
> -	{"i915_sink_crc_eDP1", i915_sink_crc, 0},
>  	{"i915_energy_uJ", i915_energy_uJ, 0},
>  	{"i915_runtime_pm_status", i915_runtime_pm_status, 0},
>  	{"i915_power_domain_info", i915_power_domain_info, 0},
> diff --git a/drivers/gpu/drm/i915/intel_dp.c
> b/drivers/gpu/drm/i915/intel_dp.c index 5be07e1d816d..efdd4b408d51 100644
> --- a/drivers/gpu/drm/i915/intel_dp.c
> +++ b/drivers/gpu/drm/i915/intel_dp.c
> @@ -3905,129 +3905,6 @@ intel_dp_configure_mst(struct intel_dp *intel_dp)
>  					intel_dp->is_mst);
>  }
> 
> -static int intel_dp_sink_crc_stop(struct intel_dp *intel_dp,
> -				  struct intel_crtc_state *crtc_state, bool disable_wa)
> -{
> -	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
> -	struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
> -	struct intel_crtc *intel_crtc = to_intel_crtc(crtc_state->base.crtc);
> -	u8 buf;
> -	int ret = 0;
> -	int count = 0;
> -	int attempts = 10;
> -
> -	if (drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_SINK, &buf) < 0) {
> -		DRM_DEBUG_KMS("Sink CRC couldn't be stopped properly\n");
> -		ret = -EIO;
> -		goto out;
> -	}
> -
> -	if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_TEST_SINK,
> -			       buf & ~DP_TEST_SINK_START) < 0) {
> -		DRM_DEBUG_KMS("Sink CRC couldn't be stopped properly\n");
> -		ret = -EIO;
> -		goto out;
> -	}
> -
> -	do {
> -		intel_wait_for_vblank(dev_priv, intel_crtc->pipe);
> -
> -		if (drm_dp_dpcd_readb(&intel_dp->aux,
> -				      DP_TEST_SINK_MISC, &buf) < 0) {
> -			ret = -EIO;
> -			goto out;
> -		}
> -		count = buf & DP_TEST_COUNT_MASK;
> -	} while (--attempts && count);
> -
> -	if (attempts == 0) {
> -		DRM_DEBUG_KMS("TIMEOUT: Sink CRC counter is not zeroed after 
calculation
> is stopped\n"); -		ret = -ETIMEDOUT;
> -	}
> -
> - out:
> -	if (disable_wa)
> -		hsw_enable_ips(crtc_state);
> -	return ret;
> -}
> -
> -static int intel_dp_sink_crc_start(struct intel_dp *intel_dp,
> -				   struct intel_crtc_state *crtc_state)
> -{
> -	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
> -	struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
> -	struct intel_crtc *intel_crtc = to_intel_crtc(crtc_state->base.crtc);
> -	u8 buf;
> -	int ret;
> -
> -	if (drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_SINK_MISC, &buf) < 0)
> -		return -EIO;
> -
> -	if (!(buf & DP_TEST_CRC_SUPPORTED))
> -		return -ENOTTY;
> -
> -	if (drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_SINK, &buf) < 0)
> -		return -EIO;
> -
> -	if (buf & DP_TEST_SINK_START) {
> -		ret = intel_dp_sink_crc_stop(intel_dp, crtc_state, false);
> -		if (ret)
> -			return ret;
> -	}
> -
> -	hsw_disable_ips(crtc_state);
> -
> -	if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_TEST_SINK,
> -			       buf | DP_TEST_SINK_START) < 0) {
> -		hsw_enable_ips(crtc_state);
> -		return -EIO;
> -	}
> -
> -	intel_wait_for_vblank(dev_priv, intel_crtc->pipe);
> -	return 0;
> -}
> -
> -int intel_dp_sink_crc(struct intel_dp *intel_dp, struct intel_crtc_state
> *crtc_state, u8 *crc) -{
> -	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
> -	struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
> -	struct intel_crtc *intel_crtc = to_intel_crtc(crtc_state->base.crtc);
> -	u8 buf;
> -	int count, ret;
> -	int attempts = 6;
> -
> -	ret = intel_dp_sink_crc_start(intel_dp, crtc_state);
> -	if (ret)
> -		return ret;
> -
> -	do {
> -		intel_wait_for_vblank(dev_priv, intel_crtc->pipe);
> -
> -		if (drm_dp_dpcd_readb(&intel_dp->aux,
> -				      DP_TEST_SINK_MISC, &buf) < 0) {
> -			ret = -EIO;
> -			goto stop;
> -		}
> -		count = buf & DP_TEST_COUNT_MASK;
> -
> -	} while (--attempts && count == 0);
> -
> -	if (attempts == 0) {
> -		DRM_ERROR("Panel is unable to calculate any CRC after 6 vblanks\n");
> -		ret = -ETIMEDOUT;
> -		goto stop;
> -	}
> -
> -	if (drm_dp_dpcd_read(&intel_dp->aux, DP_TEST_CRC_R_CR, crc, 6) < 0) {
> -		ret = -EIO;
> -		goto stop;
> -	}
> -
> -stop:
> -	intel_dp_sink_crc_stop(intel_dp, crtc_state, true);
> -	return ret;
> -}
> -
>  static bool
>  intel_dp_get_sink_irq(struct intel_dp *intel_dp, u8 *sink_irq_vector)
>  {
> diff --git a/drivers/gpu/drm/i915/intel_drv.h
> b/drivers/gpu/drm/i915/intel_drv.h index e09b42d91d1e..8e6ee2fe66e4 100644
> --- a/drivers/gpu/drm/i915/intel_drv.h
> +++ b/drivers/gpu/drm/i915/intel_drv.h
> @@ -1665,8 +1665,6 @@ void intel_dp_sink_dpms(struct intel_dp *intel_dp, int
> mode); void intel_dp_encoder_reset(struct drm_encoder *encoder);
>  void intel_dp_encoder_suspend(struct intel_encoder *intel_encoder);
>  void intel_dp_encoder_destroy(struct drm_encoder *encoder);
> -int intel_dp_sink_crc(struct intel_dp *intel_dp,
> -		      struct intel_crtc_state *crtc_state, u8 *crc);
>  bool intel_dp_compute_config(struct intel_encoder *encoder,
>  			     struct intel_crtc_state *pipe_config,
>  			     struct drm_connector_state *conn_state);
Rodrigo Vivi July 5, 2018, 9:25 p.m. UTC | #2
On Thu, Jul 05, 2018 at 02:11:45PM -0700, Dhinakaran Pandiyan wrote:
> On Thursday, July 5, 2018 12:25:28 PM PDT Rodrigo Vivi wrote:
> > It was originally introduced following the VESA spec in order to validate
> > PSR.
> > 
> > However we found so many issues around sink_crc that instead of helping PSR
> > development it only brought another layer of trouble to the table.
> > 
> > So, sink_crc has been a black whole for us in question of time, effort and
> > hope.
> > 
> > First of the problems is that HW statement is clear: "Do not attempt to use
> > aux communication with PSR enabled". So the main reason behind sink_crc is
> > already compromised.
> > 
> > For a while we had hope on the aux-mutex could workaround this problem on
> > SKL+ platforms, but that mutex was not reliable, not tested,
> > and we shouldn't use according to HW engineers.
> > 
> > Also, nor source, nor sink designed and implemented the sink_crc to be used
> > like we are trying to use here.
> > 
> > Well, the sink side of things is also apparently not prepared for this
> > case. Each panel that we tried seemed to have a different behavior with same
> > code and same source.
> > 
> > So, for all the time we lost on trying to ducktape all these different
> > issues I believe it is now time to move PSR to a more reliable validation.
> > Maybe not a perfect one as we dreamed for this sink_crc, but at least more
> > reliable.
> > 
> Good riddance.

Bye bye sink_crc, we are not going to miss you! ;)

> Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>

Thanks for granting me this honor!

now let's wait for CI to blow-up...
than when we change psr test cases we come back here, trigger a retest and
once CI is happy with push.

> 
> > Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
> > Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
> > Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
> > ---
> >  drivers/gpu/drm/i915/i915_debugfs.c |  81 ------------------
> >  drivers/gpu/drm/i915/intel_dp.c     | 123 ----------------------------
> >  drivers/gpu/drm/i915/intel_drv.h    |   2 -
> >  3 files changed, 206 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/i915_debugfs.c
> > b/drivers/gpu/drm/i915/i915_debugfs.c index f6142d78ede4..e8fa106a3655
> > 100644
> > --- a/drivers/gpu/drm/i915/i915_debugfs.c
> > +++ b/drivers/gpu/drm/i915/i915_debugfs.c
> > @@ -2761,86 +2761,6 @@ DEFINE_SIMPLE_ATTRIBUTE(i915_edp_psr_debug_fops,
> >  			i915_edp_psr_debug_get, i915_edp_psr_debug_set,
> >  			"%llu\n");
> > 
> > -static int i915_sink_crc(struct seq_file *m, void *data)
> > -{
> > -	struct drm_i915_private *dev_priv = node_to_i915(m->private);
> > -	struct drm_device *dev = &dev_priv->drm;
> > -	struct intel_connector *connector;
> > -	struct drm_connector_list_iter conn_iter;
> > -	struct intel_dp *intel_dp = NULL;
> > -	struct drm_modeset_acquire_ctx ctx;
> > -	int ret;
> > -	u8 crc[6];
> > -
> > -	drm_modeset_acquire_init(&ctx, DRM_MODESET_ACQUIRE_INTERRUPTIBLE);
> > -
> > -	drm_connector_list_iter_begin(dev, &conn_iter);
> > -
> > -	for_each_intel_connector_iter(connector, &conn_iter) {
> > -		struct drm_crtc *crtc;
> > -		struct drm_connector_state *state;
> > -		struct intel_crtc_state *crtc_state;
> > -
> > -		if (connector->base.connector_type != DRM_MODE_CONNECTOR_eDP)
> > -			continue;
> > -
> > -retry:
> > -		ret = drm_modeset_lock(&dev->mode_config.connection_mutex, &ctx);
> > -		if (ret)
> > -			goto err;
> > -
> > -		state = connector->base.state;
> > -		if (!state->best_encoder)
> > -			continue;
> > -
> > -		crtc = state->crtc;
> > -		ret = drm_modeset_lock(&crtc->mutex, &ctx);
> > -		if (ret)
> > -			goto err;
> > -
> > -		crtc_state = to_intel_crtc_state(crtc->state);
> > -		if (!crtc_state->base.active)
> > -			continue;
> > -
> > -		/*
> > -		 * We need to wait for all crtc updates to complete, to make
> > -		 * sure any pending modesets and plane updates are completed.
> > -		 */
> > -		if (crtc_state->base.commit) {
> > -			ret =
> > wait_for_completion_interruptible(&crtc_state->base.commit->hw_done); -
> > -			if (ret)
> > -				goto err;
> > -		}
> > -
> > -		intel_dp = enc_to_intel_dp(state->best_encoder);
> > -
> > -		ret = intel_dp_sink_crc(intel_dp, crtc_state, crc);
> > -		if (ret)
> > -			goto err;
> > -
> > -		seq_printf(m, "%02x%02x%02x%02x%02x%02x\n",
> > -			   crc[0], crc[1], crc[2],
> > -			   crc[3], crc[4], crc[5]);
> > -		goto out;
> > -
> > -err:
> > -		if (ret == -EDEADLK) {
> > -			ret = drm_modeset_backoff(&ctx);
> > -			if (!ret)
> > -				goto retry;
> > -		}
> > -		goto out;
> > -	}
> > -	ret = -ENODEV;
> > -out:
> > -	drm_connector_list_iter_end(&conn_iter);
> > -	drm_modeset_drop_locks(&ctx);
> > -	drm_modeset_acquire_fini(&ctx);
> > -
> > -	return ret;
> > -}
> > -
> >  static int i915_energy_uJ(struct seq_file *m, void *data)
> >  {
> >  	struct drm_i915_private *dev_priv = node_to_i915(m->private);
> > @@ -4784,7 +4704,6 @@ static const struct drm_info_list i915_debugfs_list[]
> > = { {"i915_ppgtt_info", i915_ppgtt_info, 0},
> >  	{"i915_llc", i915_llc, 0},
> >  	{"i915_edp_psr_status", i915_edp_psr_status, 0},
> > -	{"i915_sink_crc_eDP1", i915_sink_crc, 0},
> >  	{"i915_energy_uJ", i915_energy_uJ, 0},
> >  	{"i915_runtime_pm_status", i915_runtime_pm_status, 0},
> >  	{"i915_power_domain_info", i915_power_domain_info, 0},
> > diff --git a/drivers/gpu/drm/i915/intel_dp.c
> > b/drivers/gpu/drm/i915/intel_dp.c index 5be07e1d816d..efdd4b408d51 100644
> > --- a/drivers/gpu/drm/i915/intel_dp.c
> > +++ b/drivers/gpu/drm/i915/intel_dp.c
> > @@ -3905,129 +3905,6 @@ intel_dp_configure_mst(struct intel_dp *intel_dp)
> >  					intel_dp->is_mst);
> >  }
> > 
> > -static int intel_dp_sink_crc_stop(struct intel_dp *intel_dp,
> > -				  struct intel_crtc_state *crtc_state, bool disable_wa)
> > -{
> > -	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
> > -	struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
> > -	struct intel_crtc *intel_crtc = to_intel_crtc(crtc_state->base.crtc);
> > -	u8 buf;
> > -	int ret = 0;
> > -	int count = 0;
> > -	int attempts = 10;
> > -
> > -	if (drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_SINK, &buf) < 0) {
> > -		DRM_DEBUG_KMS("Sink CRC couldn't be stopped properly\n");
> > -		ret = -EIO;
> > -		goto out;
> > -	}
> > -
> > -	if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_TEST_SINK,
> > -			       buf & ~DP_TEST_SINK_START) < 0) {
> > -		DRM_DEBUG_KMS("Sink CRC couldn't be stopped properly\n");
> > -		ret = -EIO;
> > -		goto out;
> > -	}
> > -
> > -	do {
> > -		intel_wait_for_vblank(dev_priv, intel_crtc->pipe);
> > -
> > -		if (drm_dp_dpcd_readb(&intel_dp->aux,
> > -				      DP_TEST_SINK_MISC, &buf) < 0) {
> > -			ret = -EIO;
> > -			goto out;
> > -		}
> > -		count = buf & DP_TEST_COUNT_MASK;
> > -	} while (--attempts && count);
> > -
> > -	if (attempts == 0) {
> > -		DRM_DEBUG_KMS("TIMEOUT: Sink CRC counter is not zeroed after 
> calculation
> > is stopped\n"); -		ret = -ETIMEDOUT;
> > -	}
> > -
> > - out:
> > -	if (disable_wa)
> > -		hsw_enable_ips(crtc_state);
> > -	return ret;
> > -}
> > -
> > -static int intel_dp_sink_crc_start(struct intel_dp *intel_dp,
> > -				   struct intel_crtc_state *crtc_state)
> > -{
> > -	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
> > -	struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
> > -	struct intel_crtc *intel_crtc = to_intel_crtc(crtc_state->base.crtc);
> > -	u8 buf;
> > -	int ret;
> > -
> > -	if (drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_SINK_MISC, &buf) < 0)
> > -		return -EIO;
> > -
> > -	if (!(buf & DP_TEST_CRC_SUPPORTED))
> > -		return -ENOTTY;
> > -
> > -	if (drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_SINK, &buf) < 0)
> > -		return -EIO;
> > -
> > -	if (buf & DP_TEST_SINK_START) {
> > -		ret = intel_dp_sink_crc_stop(intel_dp, crtc_state, false);
> > -		if (ret)
> > -			return ret;
> > -	}
> > -
> > -	hsw_disable_ips(crtc_state);
> > -
> > -	if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_TEST_SINK,
> > -			       buf | DP_TEST_SINK_START) < 0) {
> > -		hsw_enable_ips(crtc_state);
> > -		return -EIO;
> > -	}
> > -
> > -	intel_wait_for_vblank(dev_priv, intel_crtc->pipe);
> > -	return 0;
> > -}
> > -
> > -int intel_dp_sink_crc(struct intel_dp *intel_dp, struct intel_crtc_state
> > *crtc_state, u8 *crc) -{
> > -	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
> > -	struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
> > -	struct intel_crtc *intel_crtc = to_intel_crtc(crtc_state->base.crtc);
> > -	u8 buf;
> > -	int count, ret;
> > -	int attempts = 6;
> > -
> > -	ret = intel_dp_sink_crc_start(intel_dp, crtc_state);
> > -	if (ret)
> > -		return ret;
> > -
> > -	do {
> > -		intel_wait_for_vblank(dev_priv, intel_crtc->pipe);
> > -
> > -		if (drm_dp_dpcd_readb(&intel_dp->aux,
> > -				      DP_TEST_SINK_MISC, &buf) < 0) {
> > -			ret = -EIO;
> > -			goto stop;
> > -		}
> > -		count = buf & DP_TEST_COUNT_MASK;
> > -
> > -	} while (--attempts && count == 0);
> > -
> > -	if (attempts == 0) {
> > -		DRM_ERROR("Panel is unable to calculate any CRC after 6 vblanks\n");
> > -		ret = -ETIMEDOUT;
> > -		goto stop;
> > -	}
> > -
> > -	if (drm_dp_dpcd_read(&intel_dp->aux, DP_TEST_CRC_R_CR, crc, 6) < 0) {
> > -		ret = -EIO;
> > -		goto stop;
> > -	}
> > -
> > -stop:
> > -	intel_dp_sink_crc_stop(intel_dp, crtc_state, true);
> > -	return ret;
> > -}
> > -
> >  static bool
> >  intel_dp_get_sink_irq(struct intel_dp *intel_dp, u8 *sink_irq_vector)
> >  {
> > diff --git a/drivers/gpu/drm/i915/intel_drv.h
> > b/drivers/gpu/drm/i915/intel_drv.h index e09b42d91d1e..8e6ee2fe66e4 100644
> > --- a/drivers/gpu/drm/i915/intel_drv.h
> > +++ b/drivers/gpu/drm/i915/intel_drv.h
> > @@ -1665,8 +1665,6 @@ void intel_dp_sink_dpms(struct intel_dp *intel_dp, int
> > mode); void intel_dp_encoder_reset(struct drm_encoder *encoder);
> >  void intel_dp_encoder_suspend(struct intel_encoder *intel_encoder);
> >  void intel_dp_encoder_destroy(struct drm_encoder *encoder);
> > -int intel_dp_sink_crc(struct intel_dp *intel_dp,
> > -		      struct intel_crtc_state *crtc_state, u8 *crc);
> >  bool intel_dp_compute_config(struct intel_encoder *encoder,
> >  			     struct intel_crtc_state *pipe_config,
> >  			     struct drm_connector_state *conn_state);
> 
> 
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/intel-gfx
Dhinakaran Pandiyan July 18, 2018, 7:21 p.m. UTC | #3
On Thu, 2018-07-05 at 14:25 -0700, Rodrigo Vivi wrote:
> On Thu, Jul 05, 2018 at 02:11:45PM -0700, Dhinakaran Pandiyan wrote:
> > 
> > On Thursday, July 5, 2018 12:25:28 PM PDT Rodrigo Vivi wrote:
> > > 
> > > It was originally introduced following the VESA spec in order to
> > > validate
> > > PSR.
> > > 
> > > However we found so many issues around sink_crc that instead of
> > > helping PSR
> > > development it only brought another layer of trouble to the
> > > table.
> > > 
> > > So, sink_crc has been a black whole for us in question of time,
> > > effort and
> > > hope.
> > > 
> > > First of the problems is that HW statement is clear: "Do not
> > > attempt to use
> > > aux communication with PSR enabled". So the main reason behind
> > > sink_crc is
> > > already compromised.
> > > 
> > > For a while we had hope on the aux-mutex could workaround this
> > > problem on
> > > SKL+ platforms, but that mutex was not reliable, not tested,
> > > and we shouldn't use according to HW engineers.
> > > 
> > > Also, nor source, nor sink designed and implemented the sink_crc
> > > to be used
> > > like we are trying to use here.
> > > 
> > > Well, the sink side of things is also apparently not prepared for
> > > this
> > > case. Each panel that we tried seemed to have a different
> > > behavior with same
> > > code and same source.
> > > 
> > > So, for all the time we lost on trying to ducktape all these
> > > different
> > > issues I believe it is now time to move PSR to a more reliable
> > > validation.
> > > Maybe not a perfect one as we dreamed for this sink_crc, but at
> > > least more
> > > reliable.
> > > 
> > Good riddance.
> Bye bye sink_crc, we are not going to miss you! ;)
> 
> > 
> > Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
> Thanks for granting me this honor!
> 
> now let's wait for CI to blow-up...
> than when we change psr test cases we come back here, trigger a
> retest and
> once CI is happy with push.

CI is indeed happy now.
Rodrigo Vivi July 18, 2018, 7:54 p.m. UTC | #4
On Wed, Jul 18, 2018 at 12:21:13PM -0700, Dhinakaran Pandiyan wrote:
> On Thu, 2018-07-05 at 14:25 -0700, Rodrigo Vivi wrote:
> > On Thu, Jul 05, 2018 at 02:11:45PM -0700, Dhinakaran Pandiyan wrote:
> > > 
> > > On Thursday, July 5, 2018 12:25:28 PM PDT Rodrigo Vivi wrote:
> > > > 
> > > > It was originally introduced following the VESA spec in order to
> > > > validate
> > > > PSR.
> > > > 
> > > > However we found so many issues around sink_crc that instead of
> > > > helping PSR
> > > > development it only brought another layer of trouble to the
> > > > table.
> > > > 
> > > > So, sink_crc has been a black whole for us in question of time,
> > > > effort and
> > > > hope.
> > > > 
> > > > First of the problems is that HW statement is clear: "Do not
> > > > attempt to use
> > > > aux communication with PSR enabled". So the main reason behind
> > > > sink_crc is
> > > > already compromised.
> > > > 
> > > > For a while we had hope on the aux-mutex could workaround this
> > > > problem on
> > > > SKL+ platforms, but that mutex was not reliable, not tested,
> > > > and we shouldn't use according to HW engineers.
> > > > 
> > > > Also, nor source, nor sink designed and implemented the sink_crc
> > > > to be used
> > > > like we are trying to use here.
> > > > 
> > > > Well, the sink side of things is also apparently not prepared for
> > > > this
> > > > case. Each panel that we tried seemed to have a different
> > > > behavior with same
> > > > code and same source.
> > > > 
> > > > So, for all the time we lost on trying to ducktape all these
> > > > different
> > > > issues I believe it is now time to move PSR to a more reliable
> > > > validation.
> > > > Maybe not a perfect one as we dreamed for this sink_crc, but at
> > > > least more
> > > > reliable.
> > > > 
> > > Good riddance.
> > Bye bye sink_crc, we are not going to miss you! ;)
> > 
> > > 
> > > Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
> > Thanks for granting me this honor!
> > 
> > now let's wait for CI to blow-up...
> > than when we change psr test cases we come back here, trigger a
> > retest and
> > once CI is happy with push.
> 
> CI is indeed happy now.

\o/

pushed. Thanks for granting me this honor!

>
diff mbox

Patch

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index f6142d78ede4..e8fa106a3655 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -2761,86 +2761,6 @@  DEFINE_SIMPLE_ATTRIBUTE(i915_edp_psr_debug_fops,
 			i915_edp_psr_debug_get, i915_edp_psr_debug_set,
 			"%llu\n");
 
-static int i915_sink_crc(struct seq_file *m, void *data)
-{
-	struct drm_i915_private *dev_priv = node_to_i915(m->private);
-	struct drm_device *dev = &dev_priv->drm;
-	struct intel_connector *connector;
-	struct drm_connector_list_iter conn_iter;
-	struct intel_dp *intel_dp = NULL;
-	struct drm_modeset_acquire_ctx ctx;
-	int ret;
-	u8 crc[6];
-
-	drm_modeset_acquire_init(&ctx, DRM_MODESET_ACQUIRE_INTERRUPTIBLE);
-
-	drm_connector_list_iter_begin(dev, &conn_iter);
-
-	for_each_intel_connector_iter(connector, &conn_iter) {
-		struct drm_crtc *crtc;
-		struct drm_connector_state *state;
-		struct intel_crtc_state *crtc_state;
-
-		if (connector->base.connector_type != DRM_MODE_CONNECTOR_eDP)
-			continue;
-
-retry:
-		ret = drm_modeset_lock(&dev->mode_config.connection_mutex, &ctx);
-		if (ret)
-			goto err;
-
-		state = connector->base.state;
-		if (!state->best_encoder)
-			continue;
-
-		crtc = state->crtc;
-		ret = drm_modeset_lock(&crtc->mutex, &ctx);
-		if (ret)
-			goto err;
-
-		crtc_state = to_intel_crtc_state(crtc->state);
-		if (!crtc_state->base.active)
-			continue;
-
-		/*
-		 * We need to wait for all crtc updates to complete, to make
-		 * sure any pending modesets and plane updates are completed.
-		 */
-		if (crtc_state->base.commit) {
-			ret = wait_for_completion_interruptible(&crtc_state->base.commit->hw_done);
-
-			if (ret)
-				goto err;
-		}
-
-		intel_dp = enc_to_intel_dp(state->best_encoder);
-
-		ret = intel_dp_sink_crc(intel_dp, crtc_state, crc);
-		if (ret)
-			goto err;
-
-		seq_printf(m, "%02x%02x%02x%02x%02x%02x\n",
-			   crc[0], crc[1], crc[2],
-			   crc[3], crc[4], crc[5]);
-		goto out;
-
-err:
-		if (ret == -EDEADLK) {
-			ret = drm_modeset_backoff(&ctx);
-			if (!ret)
-				goto retry;
-		}
-		goto out;
-	}
-	ret = -ENODEV;
-out:
-	drm_connector_list_iter_end(&conn_iter);
-	drm_modeset_drop_locks(&ctx);
-	drm_modeset_acquire_fini(&ctx);
-
-	return ret;
-}
-
 static int i915_energy_uJ(struct seq_file *m, void *data)
 {
 	struct drm_i915_private *dev_priv = node_to_i915(m->private);
@@ -4784,7 +4704,6 @@  static const struct drm_info_list i915_debugfs_list[] = {
 	{"i915_ppgtt_info", i915_ppgtt_info, 0},
 	{"i915_llc", i915_llc, 0},
 	{"i915_edp_psr_status", i915_edp_psr_status, 0},
-	{"i915_sink_crc_eDP1", i915_sink_crc, 0},
 	{"i915_energy_uJ", i915_energy_uJ, 0},
 	{"i915_runtime_pm_status", i915_runtime_pm_status, 0},
 	{"i915_power_domain_info", i915_power_domain_info, 0},
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 5be07e1d816d..efdd4b408d51 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -3905,129 +3905,6 @@  intel_dp_configure_mst(struct intel_dp *intel_dp)
 					intel_dp->is_mst);
 }
 
-static int intel_dp_sink_crc_stop(struct intel_dp *intel_dp,
-				  struct intel_crtc_state *crtc_state, bool disable_wa)
-{
-	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
-	struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
-	struct intel_crtc *intel_crtc = to_intel_crtc(crtc_state->base.crtc);
-	u8 buf;
-	int ret = 0;
-	int count = 0;
-	int attempts = 10;
-
-	if (drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_SINK, &buf) < 0) {
-		DRM_DEBUG_KMS("Sink CRC couldn't be stopped properly\n");
-		ret = -EIO;
-		goto out;
-	}
-
-	if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_TEST_SINK,
-			       buf & ~DP_TEST_SINK_START) < 0) {
-		DRM_DEBUG_KMS("Sink CRC couldn't be stopped properly\n");
-		ret = -EIO;
-		goto out;
-	}
-
-	do {
-		intel_wait_for_vblank(dev_priv, intel_crtc->pipe);
-
-		if (drm_dp_dpcd_readb(&intel_dp->aux,
-				      DP_TEST_SINK_MISC, &buf) < 0) {
-			ret = -EIO;
-			goto out;
-		}
-		count = buf & DP_TEST_COUNT_MASK;
-	} while (--attempts && count);
-
-	if (attempts == 0) {
-		DRM_DEBUG_KMS("TIMEOUT: Sink CRC counter is not zeroed after calculation is stopped\n");
-		ret = -ETIMEDOUT;
-	}
-
- out:
-	if (disable_wa)
-		hsw_enable_ips(crtc_state);
-	return ret;
-}
-
-static int intel_dp_sink_crc_start(struct intel_dp *intel_dp,
-				   struct intel_crtc_state *crtc_state)
-{
-	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
-	struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
-	struct intel_crtc *intel_crtc = to_intel_crtc(crtc_state->base.crtc);
-	u8 buf;
-	int ret;
-
-	if (drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_SINK_MISC, &buf) < 0)
-		return -EIO;
-
-	if (!(buf & DP_TEST_CRC_SUPPORTED))
-		return -ENOTTY;
-
-	if (drm_dp_dpcd_readb(&intel_dp->aux, DP_TEST_SINK, &buf) < 0)
-		return -EIO;
-
-	if (buf & DP_TEST_SINK_START) {
-		ret = intel_dp_sink_crc_stop(intel_dp, crtc_state, false);
-		if (ret)
-			return ret;
-	}
-
-	hsw_disable_ips(crtc_state);
-
-	if (drm_dp_dpcd_writeb(&intel_dp->aux, DP_TEST_SINK,
-			       buf | DP_TEST_SINK_START) < 0) {
-		hsw_enable_ips(crtc_state);
-		return -EIO;
-	}
-
-	intel_wait_for_vblank(dev_priv, intel_crtc->pipe);
-	return 0;
-}
-
-int intel_dp_sink_crc(struct intel_dp *intel_dp, struct intel_crtc_state *crtc_state, u8 *crc)
-{
-	struct intel_digital_port *dig_port = dp_to_dig_port(intel_dp);
-	struct drm_i915_private *dev_priv = to_i915(dig_port->base.base.dev);
-	struct intel_crtc *intel_crtc = to_intel_crtc(crtc_state->base.crtc);
-	u8 buf;
-	int count, ret;
-	int attempts = 6;
-
-	ret = intel_dp_sink_crc_start(intel_dp, crtc_state);
-	if (ret)
-		return ret;
-
-	do {
-		intel_wait_for_vblank(dev_priv, intel_crtc->pipe);
-
-		if (drm_dp_dpcd_readb(&intel_dp->aux,
-				      DP_TEST_SINK_MISC, &buf) < 0) {
-			ret = -EIO;
-			goto stop;
-		}
-		count = buf & DP_TEST_COUNT_MASK;
-
-	} while (--attempts && count == 0);
-
-	if (attempts == 0) {
-		DRM_ERROR("Panel is unable to calculate any CRC after 6 vblanks\n");
-		ret = -ETIMEDOUT;
-		goto stop;
-	}
-
-	if (drm_dp_dpcd_read(&intel_dp->aux, DP_TEST_CRC_R_CR, crc, 6) < 0) {
-		ret = -EIO;
-		goto stop;
-	}
-
-stop:
-	intel_dp_sink_crc_stop(intel_dp, crtc_state, true);
-	return ret;
-}
-
 static bool
 intel_dp_get_sink_irq(struct intel_dp *intel_dp, u8 *sink_irq_vector)
 {
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index e09b42d91d1e..8e6ee2fe66e4 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1665,8 +1665,6 @@  void intel_dp_sink_dpms(struct intel_dp *intel_dp, int mode);
 void intel_dp_encoder_reset(struct drm_encoder *encoder);
 void intel_dp_encoder_suspend(struct intel_encoder *intel_encoder);
 void intel_dp_encoder_destroy(struct drm_encoder *encoder);
-int intel_dp_sink_crc(struct intel_dp *intel_dp,
-		      struct intel_crtc_state *crtc_state, u8 *crc);
 bool intel_dp_compute_config(struct intel_encoder *encoder,
 			     struct intel_crtc_state *pipe_config,
 			     struct drm_connector_state *conn_state);