Commit 73974893 authored by Maarten Lankhorst's avatar Maarten Lankhorst Committed by Ville Syrjälä
Browse files

drm/i915: Fix modeset handling during gpu reset, v5. 



This function would call drm_modeset_lock_all, while the suspend/resume
functions already have their own locking. Fix this by factoring out
__intel_display_resume, and calling the atomic helpers for duplicating
atomic state and disabling all crtc's during suspend.

Changes since v1:
- Deal with -EDEADLK right after lock_all and clean up calls
  to hw readout.
- Always take all modeset locks so updates during gpu reset are blocked.
Changes since v2:
- Fix deadlock in intel_update_primary_planes.
- Move WARN_ON(EDEADLK) to __intel_display_resume.
- pctx -> ctx
- only call __intel_display_resume on success in intel_display_resume.
Changes since v3:
- Rebase on top of dev_priv -> dev change.
- Use drm_modeset_lock_all_ctx instead of drm_modeset_lock_all.
Changes since v4 [by vsyrjala]:
- Deal with skip_intermediate_wm
- Update comment w.r.t. mode_config.mutex vs. ->detect()
- Rebase due to INTEL_GEN() etc.

Signed-off-by: default avatarMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Fixes: e2c8b870 ("drm/i915: Use atomic helpers for suspend, v2.")
Cc: stable@vger.kernel.org
Tested-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: default avatarVille Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470428910-12125-2-git-send-email-ville.syrjala@linux.intel.com
parent a168f5b3

drivers/gpu/drm/i915/i915_drv.h

+1 −0
Original line number Diff line number Diff line
@@ -1840,6 +1840,7 @@ struct drm_i915_private { 
	enum modeset_restore modeset_restore;

	struct mutex modeset_restore_lock;

	struct drm_atomic_state *modeset_restore_state;

	struct drm_modeset_acquire_ctx reset_ctx;



	struct list_head vm_list; /* Global list of all address spaces */

	struct i915_ggtt ggtt; /* VM representing the global address space */

drivers/gpu/drm/i915/intel_display.c

+110 −60
Original line number Diff line number Diff line
@@ -3093,40 +3093,110 @@ static void intel_update_primary_planes(struct drm_device *dev) 


	for_each_crtc(dev, crtc) {

		struct intel_plane *plane = to_intel_plane(crtc->primary);

		struct intel_plane_state *plane_state;



		drm_modeset_lock_crtc(crtc, &plane->base);

		plane_state = to_intel_plane_state(plane->base.state);

		struct intel_plane_state *plane_state =

			to_intel_plane_state(plane->base.state);



		if (plane_state->visible)

			plane->update_plane(&plane->base,

					    to_intel_crtc_state(crtc->state),

					    plane_state);

	}

}



static int

__intel_display_resume(struct drm_device *dev,

		       struct drm_atomic_state *state)

{

	struct drm_crtc_state *crtc_state;

	struct drm_crtc *crtc;

	int i, ret;



	intel_modeset_setup_hw_state(dev);

	i915_redisable_vga(dev);



		drm_modeset_unlock_crtc(crtc);

	if (!state)

		return 0;



	for_each_crtc_in_state(state, crtc, crtc_state, i) {

		/*

		 * Force recalculation even if we restore

		 * current state. With fast modeset this may not result

		 * in a modeset when the state is compatible.

		 */

		crtc_state->mode_changed = true;

	}



	/* ignore any reset values/BIOS leftovers in the WM registers */

	to_intel_atomic_state(state)->skip_intermediate_wm = true;



	ret = drm_atomic_commit(state);



	WARN_ON(ret == -EDEADLK);

	return ret;

}



void intel_prepare_reset(struct drm_i915_private *dev_priv)

{

	struct drm_device *dev = &dev_priv->drm;

	struct drm_modeset_acquire_ctx *ctx = &dev_priv->reset_ctx;

	struct drm_atomic_state *state;

	int ret;



	/* no reset support for gen2 */

	if (IS_GEN2(dev_priv))

		return;



	/* reset doesn't touch the display */

	/*

	 * Need mode_config.mutex so that we don't

	 * trample ongoing ->detect() and whatnot.

	 */

	mutex_lock(&dev->mode_config.mutex);

	drm_modeset_acquire_init(ctx, 0);

	while (1) {

		ret = drm_modeset_lock_all_ctx(dev, ctx);

		if (ret != -EDEADLK)

			break;



		drm_modeset_backoff(ctx);

	}



	/* reset doesn't touch the display, but flips might get nuked anyway, */

	if (INTEL_GEN(dev_priv) >= 5 || IS_G4X(dev_priv))

		return;



	drm_modeset_lock_all(&dev_priv->drm);

	/*

	 * Disabling the crtcs gracefully seems nicer. Also the

	 * g33 docs say we should at least disable all the planes.

	 */

	intel_display_suspend(&dev_priv->drm);

	state = drm_atomic_helper_duplicate_state(dev, ctx);

	if (IS_ERR(state)) {

		ret = PTR_ERR(state);

		state = NULL;

		DRM_ERROR("Duplicating state failed with %i\n", ret);

		goto err;

	}



	ret = drm_atomic_helper_disable_all(dev, ctx);

	if (ret) {

		DRM_ERROR("Suspending crtc's failed with %i\n", ret);

		goto err;

	}



	dev_priv->modeset_restore_state = state;

	state->acquire_ctx = ctx;

	return;



err:

	drm_atomic_state_free(state);

}



void intel_finish_reset(struct drm_i915_private *dev_priv)

{

	struct drm_device *dev = &dev_priv->drm;

	struct drm_modeset_acquire_ctx *ctx = &dev_priv->reset_ctx;

	struct drm_atomic_state *state = dev_priv->modeset_restore_state;

	int ret;



	/*

	 * Flips in the rings will be nuked by the reset,

	 * so complete all pending flips so that user space
@@ -3138,6 +3208,8 @@ void intel_finish_reset(struct drm_i915_private *dev_priv) 
	if (IS_GEN2(dev_priv))

		return;



	dev_priv->modeset_restore_state = NULL;



	/* reset doesn't touch the display */

	if (INTEL_GEN(dev_priv) >= 5 || IS_G4X(dev_priv)) {

		/*
@@ -3149,10 +3221,8 @@ void intel_finish_reset(struct drm_i915_private *dev_priv) 
		 * FIXME: Atomic will make this obsolete since we won't schedule

		 * CS-based flips (which might get lost in gpu resets) any more.

		 */

		intel_update_primary_planes(&dev_priv->drm);

		return;

	}



		intel_update_primary_planes(dev);

	} else {

		/*

		 * The display has been reset as well,

		 * so need a full re-initialization.
@@ -3160,18 +3230,23 @@ void intel_finish_reset(struct drm_i915_private *dev_priv) 
		intel_runtime_pm_disable_interrupts(dev_priv);

		intel_runtime_pm_enable_interrupts(dev_priv);



	intel_modeset_init_hw(&dev_priv->drm);

		intel_modeset_init_hw(dev);



		spin_lock_irq(&dev_priv->irq_lock);

		if (dev_priv->display.hpd_irq_setup)

			dev_priv->display.hpd_irq_setup(dev_priv);

		spin_unlock_irq(&dev_priv->irq_lock);



	intel_display_resume(&dev_priv->drm);

		ret = __intel_display_resume(dev, state);

		if (ret)

			DRM_ERROR("Restoring old state failed with %i\n", ret);



		intel_hpd_init(dev_priv);

	}



	drm_modeset_unlock_all(&dev_priv->drm);

	drm_modeset_drop_locks(ctx);

	drm_modeset_acquire_fini(ctx);

	mutex_unlock(&dev->mode_config.mutex);

}



static bool intel_crtc_has_pending_flip(struct drm_crtc *crtc)
@@ -16180,9 +16255,10 @@ void intel_display_resume(struct drm_device *dev) 
	struct drm_atomic_state *state = dev_priv->modeset_restore_state;

	struct drm_modeset_acquire_ctx ctx;

	int ret;

	bool setup = false;



	dev_priv->modeset_restore_state = NULL;

	if (state)

		state->acquire_ctx = &ctx;



	/*

	 * This is a cludge because with real atomic modeset mode_config.mutex
@@ -16193,43 +16269,17 @@ void intel_display_resume(struct drm_device *dev) 
	mutex_lock(&dev->mode_config.mutex);

	drm_modeset_acquire_init(&ctx, 0);



retry:

	while (1) {

		ret = drm_modeset_lock_all_ctx(dev, &ctx);

		if (ret != -EDEADLK)

			break;



	if (ret == 0 && !setup) {

		setup = true;



		intel_modeset_setup_hw_state(dev);

		i915_redisable_vga(dev);

	}



	if (ret == 0 && state) {

		struct drm_crtc_state *crtc_state;

		struct drm_crtc *crtc;

		int i;



		state->acquire_ctx = &ctx;



		/* ignore any reset values/BIOS leftovers in the WM registers */

		to_intel_atomic_state(state)->skip_intermediate_wm = true;



		for_each_crtc_in_state(state, crtc, crtc_state, i) {

			/*

			 * Force recalculation even if we restore

			 * current state. With fast modeset this may not result

			 * in a modeset when the state is compatible.

			 */

			crtc_state->mode_changed = true;

		}



		ret = drm_atomic_commit(state);

	}



	if (ret == -EDEADLK) {

		drm_modeset_backoff(&ctx);

		goto retry;

	}



	if (!ret)

		ret = __intel_display_resume(dev, state);



	drm_modeset_drop_locks(&ctx);

	drm_modeset_acquire_fini(&ctx);

	mutex_unlock(&dev->mode_config.mutex);

CRA Git | Maintained and supported by SUSTech CRA and CCSE