/*
* 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.
*/
/**
* DOC: Frame Buffer Compression (FBC)
*
* FBC tries to save memory bandwidth (and so power consumption) by
* compressing the amount of memory used by the display. It is total
* transparent to user space and completely handled in the kernel.
*
* The benefits of FBC are mostly visible with solid backgrounds and
* variation-less patterns. It comes from keeping the memory footprint small
* and having fewer memory pages opened and accessed for refreshing the display.
*
* i915 is responsible to reserve stolen memory for FBC and configure its
* offset on proper registers. The hardware takes care of all
* compress/decompress. However there are many known cases where we have to
* forcibly disable it to allow proper screen updates.
*/
#include <drm/drm_fourcc.h>
#include "i915_drv.h"
#include "i915_trace.h"
#include "i915_vgpu.h"
#include "intel_de.h"
#include "intel_display_types.h"
#include "intel_fbc.h"
#include "intel_frontbuffer.h"
