drivers/gpu/drm/i915/intel_frontbuffer.c - kernel/msm-4.9 - Gitiles

 /*
  * Copyright © 2014 Intel Corporation
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
  * to deal in the Software without restriction, including without limitation
  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  * and/or sell copies of the Software, and to permit persons to whom the
  * Software is furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice (including the next
  * paragraph) shall be included in all copies or substantial portions of the
  * Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  * DEALINGS IN THE SOFTWARE.
  *
  * Authors:
  *	Daniel Vetter <daniel.vetter@ffwll.ch>
  */

 /**
  * DOC: frontbuffer tracking
  *
  * Many features require us to track changes to the currently active
  * frontbuffer, especially rendering targeted at the frontbuffer.
  *
  * To be able to do so GEM tracks frontbuffers using a bitmask for all possible
  * frontbuffer slots through i915_gem_track_fb(). The function in this file are
  * then called when the contents of the frontbuffer are invalidated, when
  * frontbuffer rendering has stopped again to flush out all the changes and when
  * the frontbuffer is exchanged with a flip. Subsystems interested in
  * frontbuffer changes (e.g. PSR, FBC, DRRS) should directly put their callbacks
  * into the relevant places and filter for the frontbuffer slots that they are
  * interested int.
  *
  * On a high level there are two types of powersaving features. The first one
  * work like a special cache (FBC and PSR) and are interested when they should
  * stop caching and when to restart caching. This is done by placing callbacks
  * into the invalidate and the flush functions: At invalidate the caching must
  * be stopped and at flush time it can be restarted. And maybe they need to know
  * when the frontbuffer changes (e.g. when the hw doesn't initiate an invalidate
  * and flush on its own) which can be achieved with placing callbacks into the
  * flip functions.
  *
  * The other type of display power saving feature only cares about busyness
  * (e.g. DRRS). In that case all three (invalidate, flush and flip) indicate
  * busyness. There is no direct way to detect idleness. Instead an idle timer
  * work delayed work should be started from the flush and flip functions and
  * cancelled as soon as busyness is detected.
  *
  * Note that there's also an older frontbuffer activity tracking scheme which
  * just tracks general activity. This is done by the various mark_busy and
  * mark_idle functions. For display power management features using these
  * functions is deprecated and should be avoided.
  */

 #include <drm/drmP.h>

 #include "intel_drv.h"
 #include "i915_drv.h"

 static void intel_increase_pllclock(struct drm_device *dev,
 				    enum pipe pipe)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	int dpll_reg = DPLL(pipe);
 	int dpll;

 	if (!HAS_GMCH_DISPLAY(dev))
 		return;

 	if (!dev_priv->lvds_downclock_avail)
 		return;

 	dpll = I915_READ(dpll_reg);
 	if (!HAS_PIPE_CXSR(dev) && (dpll & DISPLAY_RATE_SELECT_FPA1)) {
 		DRM_DEBUG_DRIVER("upclocking LVDS\n");

 		assert_panel_unlocked(dev_priv, pipe);

 		dpll &= ~DISPLAY_RATE_SELECT_FPA1;
 		I915_WRITE(dpll_reg, dpll);
 		intel_wait_for_vblank(dev, pipe);

 		dpll = I915_READ(dpll_reg);
 		if (dpll & DISPLAY_RATE_SELECT_FPA1)
 			DRM_DEBUG_DRIVER("failed to upclock LVDS!\n");
 	}
 }

 /**
  * intel_mark_fb_busy - mark given planes as busy
  * @dev: DRM device
  * @frontbuffer_bits: bits for the affected planes
  * @ring: optional ring for asynchronous commands
  *
  * This function gets called every time the screen contents change. It can be
  * used to keep e.g. the update rate at the nominal refresh rate with DRRS.
  */
 static void intel_mark_fb_busy(struct drm_device *dev,
 			       unsigned frontbuffer_bits,
 			       struct intel_engine_cs *ring)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	enum pipe pipe;

 	if (!i915.powersave)
 		return;

 	for_each_pipe(dev_priv, pipe) {
 		if (!(frontbuffer_bits & INTEL_FRONTBUFFER_ALL_MASK(pipe)))
 			continue;

 		intel_increase_pllclock(dev, pipe);
 	}
 }

 /**
  * intel_fb_obj_invalidate - invalidate frontbuffer object
  * @obj: GEM object to invalidate
  * @ring: set for asynchronous rendering
  * @origin: which operation caused the invalidation
  *
  * This function gets called every time rendering on the given object starts and
  * frontbuffer caching (fbc, low refresh rate for DRRS, panel self refresh) must
  * be invalidated. If @ring is non-NULL any subsequent invalidation will be delayed
  * until the rendering completes or a flip on this frontbuffer plane is
  * scheduled.
  */
 void intel_fb_obj_invalidate(struct drm_i915_gem_object *obj,
 			     struct intel_engine_cs *ring,
 			     enum fb_op_origin origin)
 {
 	struct drm_device *dev = obj->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;

 	WARN_ON(!mutex_is_locked(&dev->struct_mutex));

 	if (!obj->frontbuffer_bits)
 		return;

 	if (ring) {
 		mutex_lock(&dev_priv->fb_tracking.lock);
 		dev_priv->fb_tracking.busy_bits
 			|= obj->frontbuffer_bits;
 		dev_priv->fb_tracking.flip_bits
 			&= ~obj->frontbuffer_bits;
 		mutex_unlock(&dev_priv->fb_tracking.lock);
 	}

 	intel_mark_fb_busy(dev, obj->frontbuffer_bits, ring);

 	intel_psr_invalidate(dev, obj->frontbuffer_bits);
 	intel_edp_drrs_invalidate(dev, obj->frontbuffer_bits);
 	intel_fbc_invalidate(dev_priv, obj->frontbuffer_bits, origin);
 }

 /**
  * intel_frontbuffer_flush - flush frontbuffer
  * @dev: DRM device
  * @frontbuffer_bits: frontbuffer plane tracking bits
  *
  * This function gets called every time rendering on the given planes has
  * completed and frontbuffer caching can be started again. Flushes will get
  * delayed if they're blocked by some outstanding asynchronous rendering.
  *
  * Can be called without any locks held.
  */
 void intel_frontbuffer_flush(struct drm_device *dev,
 			     unsigned frontbuffer_bits)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;

 	/* Delay flushing when rings are still busy.*/
 	mutex_lock(&dev_priv->fb_tracking.lock);
 	frontbuffer_bits &= ~dev_priv->fb_tracking.busy_bits;
 	mutex_unlock(&dev_priv->fb_tracking.lock);

 	intel_mark_fb_busy(dev, frontbuffer_bits, NULL);

 	intel_edp_drrs_flush(dev, frontbuffer_bits);
 	intel_psr_flush(dev, frontbuffer_bits);
 	intel_fbc_flush(dev_priv, frontbuffer_bits);
 }

 /**
  * intel_fb_obj_flush - flush frontbuffer object
  * @obj: GEM object to flush
  * @retire: set when retiring asynchronous rendering
  *
  * This function gets called every time rendering on the given object has
  * completed and frontbuffer caching can be started again. If @retire is true
  * then any delayed flushes will be unblocked.
  */
 void intel_fb_obj_flush(struct drm_i915_gem_object *obj,
 			bool retire)
 {
 	struct drm_device *dev = obj->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	unsigned frontbuffer_bits;

 	WARN_ON(!mutex_is_locked(&dev->struct_mutex));

 	if (!obj->frontbuffer_bits)
 		return;

 	frontbuffer_bits = obj->frontbuffer_bits;

 	if (retire) {
 		mutex_lock(&dev_priv->fb_tracking.lock);
 		/* Filter out new bits since rendering started. */
 		frontbuffer_bits &= dev_priv->fb_tracking.busy_bits;

 		dev_priv->fb_tracking.busy_bits &= ~frontbuffer_bits;
 		mutex_unlock(&dev_priv->fb_tracking.lock);
 	}

 	intel_frontbuffer_flush(dev, frontbuffer_bits);
 }

 /**
  * intel_frontbuffer_flip_prepare - prepare asynchronous frontbuffer flip
  * @dev: DRM device
  * @frontbuffer_bits: frontbuffer plane tracking bits
  *
  * This function gets called after scheduling a flip on @obj. The actual
  * frontbuffer flushing will be delayed until completion is signalled with
  * intel_frontbuffer_flip_complete. If an invalidate happens in between this
  * flush will be cancelled.
  *
  * Can be called without any locks held.
  */
 void intel_frontbuffer_flip_prepare(struct drm_device *dev,
 				    unsigned frontbuffer_bits)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;

 	mutex_lock(&dev_priv->fb_tracking.lock);
 	dev_priv->fb_tracking.flip_bits |= frontbuffer_bits;
 	/* Remove stale busy bits due to the old buffer. */
 	dev_priv->fb_tracking.busy_bits &= ~frontbuffer_bits;
 	mutex_unlock(&dev_priv->fb_tracking.lock);
 }

 /**
  * intel_frontbuffer_flip_complete - complete asynchronous frontbuffer flip
  * @dev: DRM device
  * @frontbuffer_bits: frontbuffer plane tracking bits
  *
  * This function gets called after the flip has been latched and will complete
  * on the next vblank. It will execute the flush if it hasn't been cancelled yet.
  *
  * Can be called without any locks held.
  */
 void intel_frontbuffer_flip_complete(struct drm_device *dev,
 				     unsigned frontbuffer_bits)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;

 	mutex_lock(&dev_priv->fb_tracking.lock);
 	/* Mask any cancelled flips. */
 	frontbuffer_bits &= dev_priv->fb_tracking.flip_bits;
 	dev_priv->fb_tracking.flip_bits &= ~frontbuffer_bits;
 	mutex_unlock(&dev_priv->fb_tracking.lock);

 	intel_frontbuffer_flush(dev, frontbuffer_bits);
 }
	/*
	* Copyright © 2014 Intel Corporation
	*
	* Permission is hereby granted, free of charge, to any person obtaining a
	* copy of this software and associated documentation files (the "Software"),
	* to deal in the Software without restriction, including without limitation
	* the rights to use, copy, modify, merge, publish, distribute, sublicense,
	* and/or sell copies of the Software, and to permit persons to whom the
	* Software is furnished to do so, subject to the following conditions:
	*
	* The above copyright notice and this permission notice (including the next
	* paragraph) shall be included in all copies or substantial portions of the
	* Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
	* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
	* DEALINGS IN THE SOFTWARE.
	*
	* Authors:
	* Daniel Vetter <daniel.vetter@ffwll.ch>
	*/

	/**
	* DOC: frontbuffer tracking
	*
	* Many features require us to track changes to the currently active
	* frontbuffer, especially rendering targeted at the frontbuffer.
	*
	* To be able to do so GEM tracks frontbuffers using a bitmask for all possible
	* frontbuffer slots through i915_gem_track_fb(). The function in this file are
	* then called when the contents of the frontbuffer are invalidated, when
	* frontbuffer rendering has stopped again to flush out all the changes and when
	* the frontbuffer is exchanged with a flip. Subsystems interested in
	* frontbuffer changes (e.g. PSR, FBC, DRRS) should directly put their callbacks
	* into the relevant places and filter for the frontbuffer slots that they are
	* interested int.
	*
	* On a high level there are two types of powersaving features. The first one
	* work like a special cache (FBC and PSR) and are interested when they should
	* stop caching and when to restart caching. This is done by placing callbacks
	* into the invalidate and the flush functions: At invalidate the caching must
	* be stopped and at flush time it can be restarted. And maybe they need to know
	* when the frontbuffer changes (e.g. when the hw doesn't initiate an invalidate
	* and flush on its own) which can be achieved with placing callbacks into the
	* flip functions.
	*
	* The other type of display power saving feature only cares about busyness
	* (e.g. DRRS). In that case all three (invalidate, flush and flip) indicate
	* busyness. There is no direct way to detect idleness. Instead an idle timer
	* work delayed work should be started from the flush and flip functions and
	* cancelled as soon as busyness is detected.
	*
	* Note that there's also an older frontbuffer activity tracking scheme which
	* just tracks general activity. This is done by the various mark_busy and
	* mark_idle functions. For display power management features using these
	* functions is deprecated and should be avoided.
	*/

	#include <drm/drmP.h>

	#include "intel_drv.h"
	#include "i915_drv.h"

	static void intel_increase_pllclock(struct drm_device *dev,
	enum pipe pipe)
	{
	struct drm_i915_private *dev_priv = dev->dev_private;
	int dpll_reg = DPLL(pipe);
	int dpll;

	if (!HAS_GMCH_DISPLAY(dev))
	return;

	if (!dev_priv->lvds_downclock_avail)
	return;

	dpll = I915_READ(dpll_reg);
	if (!HAS_PIPE_CXSR(dev) && (dpll & DISPLAY_RATE_SELECT_FPA1)) {
	DRM_DEBUG_DRIVER("upclocking LVDS\n");

	assert_panel_unlocked(dev_priv, pipe);

	dpll &= ~DISPLAY_RATE_SELECT_FPA1;
	I915_WRITE(dpll_reg, dpll);
	intel_wait_for_vblank(dev, pipe);

	dpll = I915_READ(dpll_reg);
	if (dpll & DISPLAY_RATE_SELECT_FPA1)
	DRM_DEBUG_DRIVER("failed to upclock LVDS!\n");
	}
	}

	/**
	* intel_mark_fb_busy - mark given planes as busy
	* @dev: DRM device
	* @frontbuffer_bits: bits for the affected planes
	* @ring: optional ring for asynchronous commands
	*
	* This function gets called every time the screen contents change. It can be
	* used to keep e.g. the update rate at the nominal refresh rate with DRRS.
	*/
	static void intel_mark_fb_busy(struct drm_device *dev,
	unsigned frontbuffer_bits,
	struct intel_engine_cs *ring)
	{
	struct drm_i915_private *dev_priv = dev->dev_private;
	enum pipe pipe;

	if (!i915.powersave)
	return;

	for_each_pipe(dev_priv, pipe) {
	if (!(frontbuffer_bits & INTEL_FRONTBUFFER_ALL_MASK(pipe)))
	continue;

	intel_increase_pllclock(dev, pipe);
	}
	}

	/**
	* intel_fb_obj_invalidate - invalidate frontbuffer object
	* @obj: GEM object to invalidate
	* @ring: set for asynchronous rendering
	* @origin: which operation caused the invalidation
	*
	* This function gets called every time rendering on the given object starts and
	* frontbuffer caching (fbc, low refresh rate for DRRS, panel self refresh) must
	* be invalidated. If @ring is non-NULL any subsequent invalidation will be delayed
	* until the rendering completes or a flip on this frontbuffer plane is
	* scheduled.
	*/
	void intel_fb_obj_invalidate(struct drm_i915_gem_object *obj,
	struct intel_engine_cs *ring,
	enum fb_op_origin origin)
	{
	struct drm_device *dev = obj->base.dev;
	struct drm_i915_private *dev_priv = dev->dev_private;

	WARN_ON(!mutex_is_locked(&dev->struct_mutex));

	if (!obj->frontbuffer_bits)
	return;

	if (ring) {
	mutex_lock(&dev_priv->fb_tracking.lock);
	dev_priv->fb_tracking.busy_bits
	\|= obj->frontbuffer_bits;
	dev_priv->fb_tracking.flip_bits
	&= ~obj->frontbuffer_bits;
	mutex_unlock(&dev_priv->fb_tracking.lock);
	}

	intel_mark_fb_busy(dev, obj->frontbuffer_bits, ring);

	intel_psr_invalidate(dev, obj->frontbuffer_bits);
	intel_edp_drrs_invalidate(dev, obj->frontbuffer_bits);
	intel_fbc_invalidate(dev_priv, obj->frontbuffer_bits, origin);
	}

	/**
	* intel_frontbuffer_flush - flush frontbuffer
	* @dev: DRM device
	* @frontbuffer_bits: frontbuffer plane tracking bits
	*
	* This function gets called every time rendering on the given planes has
	* completed and frontbuffer caching can be started again. Flushes will get
	* delayed if they're blocked by some outstanding asynchronous rendering.
	*
	* Can be called without any locks held.
	*/
	void intel_frontbuffer_flush(struct drm_device *dev,
	unsigned frontbuffer_bits)
	{
	struct drm_i915_private *dev_priv = dev->dev_private;

	/* Delay flushing when rings are still busy.*/
	mutex_lock(&dev_priv->fb_tracking.lock);
	frontbuffer_bits &= ~dev_priv->fb_tracking.busy_bits;
	mutex_unlock(&dev_priv->fb_tracking.lock);

	intel_mark_fb_busy(dev, frontbuffer_bits, NULL);

	intel_edp_drrs_flush(dev, frontbuffer_bits);
	intel_psr_flush(dev, frontbuffer_bits);
	intel_fbc_flush(dev_priv, frontbuffer_bits);
	}

	/**
	* intel_fb_obj_flush - flush frontbuffer object
	* @obj: GEM object to flush
	* @retire: set when retiring asynchronous rendering
	*
	* This function gets called every time rendering on the given object has
	* completed and frontbuffer caching can be started again. If @retire is true
	* then any delayed flushes will be unblocked.
	*/
	void intel_fb_obj_flush(struct drm_i915_gem_object *obj,
	bool retire)
	{
	struct drm_device *dev = obj->base.dev;
	struct drm_i915_private *dev_priv = dev->dev_private;
	unsigned frontbuffer_bits;

	WARN_ON(!mutex_is_locked(&dev->struct_mutex));

	if (!obj->frontbuffer_bits)
	return;

	frontbuffer_bits = obj->frontbuffer_bits;

	if (retire) {
	mutex_lock(&dev_priv->fb_tracking.lock);
	/* Filter out new bits since rendering started. */
	frontbuffer_bits &= dev_priv->fb_tracking.busy_bits;

	dev_priv->fb_tracking.busy_bits &= ~frontbuffer_bits;
	mutex_unlock(&dev_priv->fb_tracking.lock);
	}

	intel_frontbuffer_flush(dev, frontbuffer_bits);
	}

	/**
	* intel_frontbuffer_flip_prepare - prepare asynchronous frontbuffer flip
	* @dev: DRM device
	* @frontbuffer_bits: frontbuffer plane tracking bits
	*
	* This function gets called after scheduling a flip on @obj. The actual
	* frontbuffer flushing will be delayed until completion is signalled with
	* intel_frontbuffer_flip_complete. If an invalidate happens in between this
	* flush will be cancelled.
	*
	* Can be called without any locks held.
	*/
	void intel_frontbuffer_flip_prepare(struct drm_device *dev,
	unsigned frontbuffer_bits)
	{
	struct drm_i915_private *dev_priv = dev->dev_private;

	mutex_lock(&dev_priv->fb_tracking.lock);
	dev_priv->fb_tracking.flip_bits \|= frontbuffer_bits;
	/* Remove stale busy bits due to the old buffer. */
	dev_priv->fb_tracking.busy_bits &= ~frontbuffer_bits;
	mutex_unlock(&dev_priv->fb_tracking.lock);
	}

	/**
	* intel_frontbuffer_flip_complete - complete asynchronous frontbuffer flip
	* @dev: DRM device
	* @frontbuffer_bits: frontbuffer plane tracking bits
	*
	* This function gets called after the flip has been latched and will complete
	* on the next vblank. It will execute the flush if it hasn't been cancelled yet.
	*
	* Can be called without any locks held.
	*/
	void intel_frontbuffer_flip_complete(struct drm_device *dev,
	unsigned frontbuffer_bits)
	{
	struct drm_i915_private *dev_priv = dev->dev_private;

	mutex_lock(&dev_priv->fb_tracking.lock);
	/* Mask any cancelled flips. */
	frontbuffer_bits &= dev_priv->fb_tracking.flip_bits;
	dev_priv->fb_tracking.flip_bits &= ~frontbuffer_bits;
	mutex_unlock(&dev_priv->fb_tracking.lock);

	intel_frontbuffer_flush(dev, frontbuffer_bits);
	}