diff options
Diffstat (limited to 'drivers/gpu/drm/i915/display/intel_frontbuffer.c')
| -rw-r--r-- | drivers/gpu/drm/i915/display/intel_frontbuffer.c | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_frontbuffer.c b/drivers/gpu/drm/i915/display/intel_frontbuffer.c new file mode 100644 index 000000000000..44273c10cea5 --- /dev/null +++ b/drivers/gpu/drm/i915/display/intel_frontbuffer.c @@ -0,0 +1,199 @@ +/* + * 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. + */ + +#include "display/intel_dp.h" + +#include "i915_drv.h" +#include "intel_drv.h" +#include "intel_fbc.h" +#include "intel_frontbuffer.h" +#include "intel_psr.h" + +void __intel_fb_obj_invalidate(struct drm_i915_gem_object *obj, + enum fb_op_origin origin, + unsigned int frontbuffer_bits) +{ + struct drm_i915_private *dev_priv = to_i915(obj->base.dev); + + if (origin == ORIGIN_CS) { + spin_lock(&dev_priv->fb_tracking.lock); + dev_priv->fb_tracking.busy_bits |= frontbuffer_bits; + dev_priv->fb_tracking.flip_bits &= ~frontbuffer_bits; + spin_unlock(&dev_priv->fb_tracking.lock); + } + + might_sleep(); + intel_psr_invalidate(dev_priv, frontbuffer_bits, origin); + intel_edp_drrs_invalidate(dev_priv, frontbuffer_bits); + intel_fbc_invalidate(dev_priv, frontbuffer_bits, origin); +} + +/** + * intel_frontbuffer_flush - flush frontbuffer + * @dev_priv: i915 device + * @frontbuffer_bits: frontbuffer plane tracking bits + * @origin: which operation caused the flush + * + * 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. + */ +static void intel_frontbuffer_flush(struct drm_i915_private *dev_priv, + unsigned frontbuffer_bits, + enum fb_op_origin origin) +{ + /* Delay flushing when rings are still busy.*/ + spin_lock(&dev_priv->fb_tracking.lock); + frontbuffer_bits &= ~dev_priv->fb_tracking.busy_bits; + spin_unlock(&dev_priv->fb_tracking.lock); + + if (!frontbuffer_bits) + return; + + might_sleep(); + intel_edp_drrs_flush(dev_priv, frontbuffer_bits); + intel_psr_flush(dev_priv, frontbuffer_bits, origin); + intel_fbc_flush(dev_priv, frontbuffer_bits, origin); +} + +void __intel_fb_obj_flush(struct drm_i915_gem_object *obj, + enum fb_op_origin origin, + unsigned int frontbuffer_bits) +{ + struct drm_i915_private *dev_priv = to_i915(obj->base.dev); + + if (origin == ORIGIN_CS) { + spin_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; + spin_unlock(&dev_priv->fb_tracking.lock); + } + + if (frontbuffer_bits) + intel_frontbuffer_flush(dev_priv, frontbuffer_bits, origin); +} + +/** + * intel_frontbuffer_flip_prepare - prepare asynchronous frontbuffer flip + * @dev_priv: i915 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_i915_private *dev_priv, + unsigned frontbuffer_bits) +{ + spin_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; + spin_unlock(&dev_priv->fb_tracking.lock); +} + +/** + * intel_frontbuffer_flip_complete - complete asynchronous frontbuffer flip + * @dev_priv: i915 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_i915_private *dev_priv, + unsigned frontbuffer_bits) +{ + spin_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; + spin_unlock(&dev_priv->fb_tracking.lock); + + if (frontbuffer_bits) + intel_frontbuffer_flush(dev_priv, + frontbuffer_bits, ORIGIN_FLIP); +} + +/** + * intel_frontbuffer_flip - synchronous frontbuffer flip + * @dev_priv: i915 device + * @frontbuffer_bits: frontbuffer plane tracking bits + * + * This function gets called after scheduling a flip on @obj. This is for + * synchronous plane updates which will happen on the next vblank and which will + * not get delayed by pending gpu rendering. + * + * Can be called without any locks held. + */ +void intel_frontbuffer_flip(struct drm_i915_private *dev_priv, + unsigned frontbuffer_bits) +{ + spin_lock(&dev_priv->fb_tracking.lock); + /* Remove stale busy bits due to the old buffer. */ + dev_priv->fb_tracking.busy_bits &= ~frontbuffer_bits; + spin_unlock(&dev_priv->fb_tracking.lock); + + intel_frontbuffer_flush(dev_priv, frontbuffer_bits, ORIGIN_FLIP); +} |