[SRU,Bionic,1/1] UBUNTU: SAUCE: Revert "drm/i915/edp: Allow alternate fixed mode for eDP if available."

Message ID f77a5287fbcc380b2fa83c18b4c03634517ff0d0.1527700585.git.joseph.salisbury@canonical.com
State New
Headers show
Series
  • UBUNTU: SAUCE: Revert "drm/i915/edp: Allow alternate fixed mode for eDP if available."
Related show

Commit Message

Joseph Salisbury June 1, 2018, 3:46 p.m.
From: Jani Nikula <jani.nikula@intel.com>

BugLink: http://bugs.launchpad.net/bugs/1773520

This reverts commit dc911f5bd8aacfcf8aabd5c26c88e04c837a938e.

Per the report, no matter what display mode you select with xrandr, the
i915 driver will always select the alternate fixed mode. For the
reporter this means that the display will always run at 40Hz which is
quite annoying. This may be due to the mode comparison.

But there are some other potential issues. The choice of alt_fixed_mode
seems dubious. It's the first non-preferred mode, but there are no
guarantees that the only difference would be refresh rate. Similarly,
there may be more than one preferred mode in the probed modes list, and
the commit changes the preferred mode selection to choose the last one
on the list instead of the first.

(Note that the probed modes list is the raw, unfiltered, unsorted list
of modes from drm_add_edid_modes(), not the pretty result after a
drm_helper_probe_single_connector_modes() call.)

Finally, we already have eerily similar code in place to find the
downclock mode for DRRS that seems like could be reused here.

Back to the drawing board.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=105469
Reported-by: Rune Petersen <rune@megahurts.dk>
Reported-by: Mark Spencer <n7u4722r35@ynzlx.anonbox.net>
Fixes: dc911f5bd8aa ("drm/i915/edp: Allow alternate fixed mode for eDP if available.")
Cc: Clint Taylor <clinton.a.taylor@intel.com>
Cc: David Weinehall <david.weinehall@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jim Bride <jim.bride@linux.intel.com>
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: intel-gfx@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v4.14+
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180516080110.22770-1-jani.nikula@intel.com
Signed-off-by: Joseph Salisbury <joseph.salisbury@canonical.com>
---
 drivers/gpu/drm/i915/intel_dp.c    | 38 +++++---------------------------------
 drivers/gpu/drm/i915/intel_drv.h   |  2 --
 drivers/gpu/drm/i915/intel_dsi.c   |  2 +-
 drivers/gpu/drm/i915/intel_dvo.c   |  2 +-
 drivers/gpu/drm/i915/intel_lvds.c  |  3 +--
 drivers/gpu/drm/i915/intel_panel.c |  6 ------
 6 files changed, 8 insertions(+), 45 deletions(-)

Comments

Kleber Souza June 5, 2018, 6:31 p.m. | #1
On 06/01/18 08:46, Joseph Salisbury wrote:
> From: Jani Nikula <jani.nikula@intel.com>
> 
> BugLink: http://bugs.launchpad.net/bugs/1773520
> 
> This reverts commit dc911f5bd8aacfcf8aabd5c26c88e04c837a938e.
> 
> Per the report, no matter what display mode you select with xrandr, the
> i915 driver will always select the alternate fixed mode. For the
> reporter this means that the display will always run at 40Hz which is
> quite annoying. This may be due to the mode comparison.
> 
> But there are some other potential issues. The choice of alt_fixed_mode
> seems dubious. It's the first non-preferred mode, but there are no
> guarantees that the only difference would be refresh rate. Similarly,
> there may be more than one preferred mode in the probed modes list, and
> the commit changes the preferred mode selection to choose the last one
> on the list instead of the first.
> 
> (Note that the probed modes list is the raw, unfiltered, unsorted list
> of modes from drm_add_edid_modes(), not the pretty result after a
> drm_helper_probe_single_connector_modes() call.)
> 
> Finally, we already have eerily similar code in place to find the
> downclock mode for DRRS that seems like could be reused here.
> 
> Back to the drawing board.
> 
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=105469
> Reported-by: Rune Petersen <rune@megahurts.dk>
> Reported-by: Mark Spencer <n7u4722r35@ynzlx.anonbox.net>
> Fixes: dc911f5bd8aa ("drm/i915/edp: Allow alternate fixed mode for eDP if available.")
> Cc: Clint Taylor <clinton.a.taylor@intel.com>
> Cc: David Weinehall <david.weinehall@linux.intel.com>
> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
> Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
> Cc: Jani Nikula <jani.nikula@intel.com>
> Cc: Chris Wilson <chris@chris-wilson.co.uk>
> Cc: Jim Bride <jim.bride@linux.intel.com>
> Cc: Jani Nikula <jani.nikula@linux.intel.com>
> Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
> Cc: intel-gfx@lists.freedesktop.org
> Cc: <stable@vger.kernel.org> # v4.14+
> Signed-off-by: Jani Nikula <jani.nikula@intel.com>
> Reviewed-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
> Link: https://patchwork.freedesktop.org/patch/msgid/20180516080110.22770-1-jani.nikula@intel.com
> Signed-off-by: Joseph Salisbury <joseph.salisbury@canonical.com>

Acked-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com>

> ---
>  drivers/gpu/drm/i915/intel_dp.c    | 38 +++++---------------------------------
>  drivers/gpu/drm/i915/intel_drv.h   |  2 --
>  drivers/gpu/drm/i915/intel_dsi.c   |  2 +-
>  drivers/gpu/drm/i915/intel_dvo.c   |  2 +-
>  drivers/gpu/drm/i915/intel_lvds.c  |  3 +--
>  drivers/gpu/drm/i915/intel_panel.c |  6 ------
>  6 files changed, 8 insertions(+), 45 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> index add4b24..0dace06 100644
> --- a/drivers/gpu/drm/i915/intel_dp.c
> +++ b/drivers/gpu/drm/i915/intel_dp.c
> @@ -1603,23 +1603,6 @@ static int intel_dp_compute_bpp(struct intel_dp *intel_dp,
>  	return bpp;
>  }
>  
> -static bool intel_edp_compare_alt_mode(struct drm_display_mode *m1,
> -				       struct drm_display_mode *m2)
> -{
> -	bool bres = false;
> -
> -	if (m1 && m2)
> -		bres = (m1->hdisplay == m2->hdisplay &&
> -			m1->hsync_start == m2->hsync_start &&
> -			m1->hsync_end == m2->hsync_end &&
> -			m1->htotal == m2->htotal &&
> -			m1->vdisplay == m2->vdisplay &&
> -			m1->vsync_start == m2->vsync_start &&
> -			m1->vsync_end == m2->vsync_end &&
> -			m1->vtotal == m2->vtotal);
> -	return bres;
> -}
> -
>  bool
>  intel_dp_compute_config(struct intel_encoder *encoder,
>  			struct intel_crtc_state *pipe_config,
> @@ -1666,16 +1649,8 @@ intel_dp_compute_config(struct intel_encoder *encoder,
>  		pipe_config->has_audio = intel_conn_state->force_audio == HDMI_AUDIO_ON;
>  
>  	if (intel_dp_is_edp(intel_dp) && intel_connector->panel.fixed_mode) {
> -		struct drm_display_mode *panel_mode =
> -			intel_connector->panel.alt_fixed_mode;
> -		struct drm_display_mode *req_mode = &pipe_config->base.mode;
> -
> -		if (!intel_edp_compare_alt_mode(req_mode, panel_mode))
> -			panel_mode = intel_connector->panel.fixed_mode;
> -
> -		drm_mode_debug_printmodeline(panel_mode);
> -
> -		intel_fixed_panel_mode(panel_mode, adjusted_mode);
> +		intel_fixed_panel_mode(intel_connector->panel.fixed_mode,
> +				       adjusted_mode);
>  
>  		if (INTEL_GEN(dev_priv) >= 9) {
>  			int ret;
> @@ -5828,7 +5803,6 @@ static bool intel_edp_init_connector(struct intel_dp *intel_dp,
>  	struct drm_device *dev = intel_encoder->base.dev;
>  	struct drm_i915_private *dev_priv = to_i915(dev);
>  	struct drm_display_mode *fixed_mode = NULL;
> -	struct drm_display_mode *alt_fixed_mode = NULL;
>  	struct drm_display_mode *downclock_mode = NULL;
>  	bool has_dpcd;
>  	struct drm_display_mode *scan;
> @@ -5884,14 +5858,13 @@ static bool intel_edp_init_connector(struct intel_dp *intel_dp,
>  	}
>  	intel_connector->edid = edid;
>  
> -	/* prefer fixed mode from EDID if available, save an alt mode also */
> +	/* prefer fixed mode from EDID if available */
>  	list_for_each_entry(scan, &connector->probed_modes, head) {
>  		if ((scan->type & DRM_MODE_TYPE_PREFERRED)) {
>  			fixed_mode = drm_mode_duplicate(dev, scan);
>  			downclock_mode = intel_dp_drrs_init(
>  						intel_connector, fixed_mode);
> -		} else if (!alt_fixed_mode) {
> -			alt_fixed_mode = drm_mode_duplicate(dev, scan);
> +			break;
>  		}
>  	}
>  
> @@ -5928,8 +5901,7 @@ static bool intel_edp_init_connector(struct intel_dp *intel_dp,
>  			      pipe_name(pipe));
>  	}
>  
> -	intel_panel_init(&intel_connector->panel, fixed_mode, alt_fixed_mode,
> -			 downclock_mode);
> +	intel_panel_init(&intel_connector->panel, fixed_mode, downclock_mode);
>  	intel_connector->panel.backlight.power = intel_edp_backlight_power;
>  	intel_panel_setup_backlight(connector, pipe);
>  
> diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
> index 5d77f75..aa8097b 100644
> --- a/drivers/gpu/drm/i915/intel_drv.h
> +++ b/drivers/gpu/drm/i915/intel_drv.h
> @@ -265,7 +265,6 @@ struct intel_encoder {
>  
>  struct intel_panel {
>  	struct drm_display_mode *fixed_mode;
> -	struct drm_display_mode *alt_fixed_mode;
>  	struct drm_display_mode *downclock_mode;
>  
>  	/* backlight */
> @@ -1708,7 +1707,6 @@ void intel_overlay_reset(struct drm_i915_private *dev_priv);
>  /* intel_panel.c */
>  int intel_panel_init(struct intel_panel *panel,
>  		     struct drm_display_mode *fixed_mode,
> -		     struct drm_display_mode *alt_fixed_mode,
>  		     struct drm_display_mode *downclock_mode);
>  void intel_panel_fini(struct intel_panel *panel);
>  void intel_fixed_panel_mode(const struct drm_display_mode *fixed_mode,
> diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c
> index 83f1584..d1deb74 100644
> --- a/drivers/gpu/drm/i915/intel_dsi.c
> +++ b/drivers/gpu/drm/i915/intel_dsi.c
> @@ -1822,7 +1822,7 @@ void intel_dsi_init(struct drm_i915_private *dev_priv)
>  	connector->display_info.width_mm = fixed_mode->width_mm;
>  	connector->display_info.height_mm = fixed_mode->height_mm;
>  
> -	intel_panel_init(&intel_connector->panel, fixed_mode, NULL, NULL);
> +	intel_panel_init(&intel_connector->panel, fixed_mode, NULL);
>  	intel_panel_setup_backlight(connector, INVALID_PIPE);
>  
>  	intel_dsi_add_properties(intel_connector);
> diff --git a/drivers/gpu/drm/i915/intel_dvo.c b/drivers/gpu/drm/i915/intel_dvo.c
> index 53c9b76..2b99904 100644
> --- a/drivers/gpu/drm/i915/intel_dvo.c
> +++ b/drivers/gpu/drm/i915/intel_dvo.c
> @@ -535,7 +535,7 @@ void intel_dvo_init(struct drm_i915_private *dev_priv)
>  			 */
>  			intel_panel_init(&intel_connector->panel,
>  					 intel_dvo_get_current_mode(intel_encoder),
> -					 NULL, NULL);
> +					 NULL);
>  			intel_dvo->panel_wants_dither = true;
>  		}
>  
> diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
> index 38572d6..885d349 100644
> --- a/drivers/gpu/drm/i915/intel_lvds.c
> +++ b/drivers/gpu/drm/i915/intel_lvds.c
> @@ -1125,8 +1125,7 @@ void intel_lvds_init(struct drm_i915_private *dev_priv)
>  out:
>  	mutex_unlock(&dev->mode_config.mutex);
>  
> -	intel_panel_init(&intel_connector->panel, fixed_mode, NULL,
> -			 downclock_mode);
> +	intel_panel_init(&intel_connector->panel, fixed_mode, downclock_mode);
>  	intel_panel_setup_backlight(connector, INVALID_PIPE);
>  
>  	lvds_encoder->is_dual_link = compute_is_dual_link_lvds(lvds_encoder);
> diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
> index adc51e4..76f3aa5 100644
> --- a/drivers/gpu/drm/i915/intel_panel.c
> +++ b/drivers/gpu/drm/i915/intel_panel.c
> @@ -1924,13 +1924,11 @@ intel_panel_init_backlight_funcs(struct intel_panel *panel)
>  
>  int intel_panel_init(struct intel_panel *panel,
>  		     struct drm_display_mode *fixed_mode,
> -		     struct drm_display_mode *alt_fixed_mode,
>  		     struct drm_display_mode *downclock_mode)
>  {
>  	intel_panel_init_backlight_funcs(panel);
>  
>  	panel->fixed_mode = fixed_mode;
> -	panel->alt_fixed_mode = alt_fixed_mode;
>  	panel->downclock_mode = downclock_mode;
>  
>  	return 0;
> @@ -1944,10 +1942,6 @@ void intel_panel_fini(struct intel_panel *panel)
>  	if (panel->fixed_mode)
>  		drm_mode_destroy(intel_connector->base.dev, panel->fixed_mode);
>  
> -	if (panel->alt_fixed_mode)
> -		drm_mode_destroy(intel_connector->base.dev,
> -				panel->alt_fixed_mode);
> -
>  	if (panel->downclock_mode)
>  		drm_mode_destroy(intel_connector->base.dev,
>  				panel->downclock_mode);
>

Patch

diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index add4b24..0dace06 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -1603,23 +1603,6 @@  static int intel_dp_compute_bpp(struct intel_dp *intel_dp,
 	return bpp;
 }
 
-static bool intel_edp_compare_alt_mode(struct drm_display_mode *m1,
-				       struct drm_display_mode *m2)
-{
-	bool bres = false;
-
-	if (m1 && m2)
-		bres = (m1->hdisplay == m2->hdisplay &&
-			m1->hsync_start == m2->hsync_start &&
-			m1->hsync_end == m2->hsync_end &&
-			m1->htotal == m2->htotal &&
-			m1->vdisplay == m2->vdisplay &&
-			m1->vsync_start == m2->vsync_start &&
-			m1->vsync_end == m2->vsync_end &&
-			m1->vtotal == m2->vtotal);
-	return bres;
-}
-
 bool
 intel_dp_compute_config(struct intel_encoder *encoder,
 			struct intel_crtc_state *pipe_config,
@@ -1666,16 +1649,8 @@  intel_dp_compute_config(struct intel_encoder *encoder,
 		pipe_config->has_audio = intel_conn_state->force_audio == HDMI_AUDIO_ON;
 
 	if (intel_dp_is_edp(intel_dp) && intel_connector->panel.fixed_mode) {
-		struct drm_display_mode *panel_mode =
-			intel_connector->panel.alt_fixed_mode;
-		struct drm_display_mode *req_mode = &pipe_config->base.mode;
-
-		if (!intel_edp_compare_alt_mode(req_mode, panel_mode))
-			panel_mode = intel_connector->panel.fixed_mode;
-
-		drm_mode_debug_printmodeline(panel_mode);
-
-		intel_fixed_panel_mode(panel_mode, adjusted_mode);
+		intel_fixed_panel_mode(intel_connector->panel.fixed_mode,
+				       adjusted_mode);
 
 		if (INTEL_GEN(dev_priv) >= 9) {
 			int ret;
@@ -5828,7 +5803,6 @@  static bool intel_edp_init_connector(struct intel_dp *intel_dp,
 	struct drm_device *dev = intel_encoder->base.dev;
 	struct drm_i915_private *dev_priv = to_i915(dev);
 	struct drm_display_mode *fixed_mode = NULL;
-	struct drm_display_mode *alt_fixed_mode = NULL;
 	struct drm_display_mode *downclock_mode = NULL;
 	bool has_dpcd;
 	struct drm_display_mode *scan;
@@ -5884,14 +5858,13 @@  static bool intel_edp_init_connector(struct intel_dp *intel_dp,
 	}
 	intel_connector->edid = edid;
 
-	/* prefer fixed mode from EDID if available, save an alt mode also */
+	/* prefer fixed mode from EDID if available */
 	list_for_each_entry(scan, &connector->probed_modes, head) {
 		if ((scan->type & DRM_MODE_TYPE_PREFERRED)) {
 			fixed_mode = drm_mode_duplicate(dev, scan);
 			downclock_mode = intel_dp_drrs_init(
 						intel_connector, fixed_mode);
-		} else if (!alt_fixed_mode) {
-			alt_fixed_mode = drm_mode_duplicate(dev, scan);
+			break;
 		}
 	}
 
@@ -5928,8 +5901,7 @@  static bool intel_edp_init_connector(struct intel_dp *intel_dp,
 			      pipe_name(pipe));
 	}
 
-	intel_panel_init(&intel_connector->panel, fixed_mode, alt_fixed_mode,
-			 downclock_mode);
+	intel_panel_init(&intel_connector->panel, fixed_mode, downclock_mode);
 	intel_connector->panel.backlight.power = intel_edp_backlight_power;
 	intel_panel_setup_backlight(connector, pipe);
 
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 5d77f75..aa8097b 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -265,7 +265,6 @@  struct intel_encoder {
 
 struct intel_panel {
 	struct drm_display_mode *fixed_mode;
-	struct drm_display_mode *alt_fixed_mode;
 	struct drm_display_mode *downclock_mode;
 
 	/* backlight */
@@ -1708,7 +1707,6 @@  void intel_overlay_reset(struct drm_i915_private *dev_priv);
 /* intel_panel.c */
 int intel_panel_init(struct intel_panel *panel,
 		     struct drm_display_mode *fixed_mode,
-		     struct drm_display_mode *alt_fixed_mode,
 		     struct drm_display_mode *downclock_mode);
 void intel_panel_fini(struct intel_panel *panel);
 void intel_fixed_panel_mode(const struct drm_display_mode *fixed_mode,
diff --git a/drivers/gpu/drm/i915/intel_dsi.c b/drivers/gpu/drm/i915/intel_dsi.c
index 83f1584..d1deb74 100644
--- a/drivers/gpu/drm/i915/intel_dsi.c
+++ b/drivers/gpu/drm/i915/intel_dsi.c
@@ -1822,7 +1822,7 @@  void intel_dsi_init(struct drm_i915_private *dev_priv)
 	connector->display_info.width_mm = fixed_mode->width_mm;
 	connector->display_info.height_mm = fixed_mode->height_mm;
 
-	intel_panel_init(&intel_connector->panel, fixed_mode, NULL, NULL);
+	intel_panel_init(&intel_connector->panel, fixed_mode, NULL);
 	intel_panel_setup_backlight(connector, INVALID_PIPE);
 
 	intel_dsi_add_properties(intel_connector);
diff --git a/drivers/gpu/drm/i915/intel_dvo.c b/drivers/gpu/drm/i915/intel_dvo.c
index 53c9b76..2b99904 100644
--- a/drivers/gpu/drm/i915/intel_dvo.c
+++ b/drivers/gpu/drm/i915/intel_dvo.c
@@ -535,7 +535,7 @@  void intel_dvo_init(struct drm_i915_private *dev_priv)
 			 */
 			intel_panel_init(&intel_connector->panel,
 					 intel_dvo_get_current_mode(intel_encoder),
-					 NULL, NULL);
+					 NULL);
 			intel_dvo->panel_wants_dither = true;
 		}
 
diff --git a/drivers/gpu/drm/i915/intel_lvds.c b/drivers/gpu/drm/i915/intel_lvds.c
index 38572d6..885d349 100644
--- a/drivers/gpu/drm/i915/intel_lvds.c
+++ b/drivers/gpu/drm/i915/intel_lvds.c
@@ -1125,8 +1125,7 @@  void intel_lvds_init(struct drm_i915_private *dev_priv)
 out:
 	mutex_unlock(&dev->mode_config.mutex);
 
-	intel_panel_init(&intel_connector->panel, fixed_mode, NULL,
-			 downclock_mode);
+	intel_panel_init(&intel_connector->panel, fixed_mode, downclock_mode);
 	intel_panel_setup_backlight(connector, INVALID_PIPE);
 
 	lvds_encoder->is_dual_link = compute_is_dual_link_lvds(lvds_encoder);
diff --git a/drivers/gpu/drm/i915/intel_panel.c b/drivers/gpu/drm/i915/intel_panel.c
index adc51e4..76f3aa5 100644
--- a/drivers/gpu/drm/i915/intel_panel.c
+++ b/drivers/gpu/drm/i915/intel_panel.c
@@ -1924,13 +1924,11 @@  intel_panel_init_backlight_funcs(struct intel_panel *panel)
 
 int intel_panel_init(struct intel_panel *panel,
 		     struct drm_display_mode *fixed_mode,
-		     struct drm_display_mode *alt_fixed_mode,
 		     struct drm_display_mode *downclock_mode)
 {
 	intel_panel_init_backlight_funcs(panel);
 
 	panel->fixed_mode = fixed_mode;
-	panel->alt_fixed_mode = alt_fixed_mode;
 	panel->downclock_mode = downclock_mode;
 
 	return 0;
@@ -1944,10 +1942,6 @@  void intel_panel_fini(struct intel_panel *panel)
 	if (panel->fixed_mode)
 		drm_mode_destroy(intel_connector->base.dev, panel->fixed_mode);
 
-	if (panel->alt_fixed_mode)
-		drm_mode_destroy(intel_connector->base.dev,
-				panel->alt_fixed_mode);
-
 	if (panel->downclock_mode)
 		drm_mode_destroy(intel_connector->base.dev,
 				panel->downclock_mode);