blob: 34be4c0ee7c59a3d9b64a8219d224f28ed6c52ca [file] [log] [blame]
* SPDX-License-Identifier: MIT
* Copyright © 2016 Intel Corporation
#include "display/intel_frontbuffer.h"
#include "i915_drv.h"
#include "i915_gem_clflush.h"
#include "i915_sw_fence_work.h"
#include "i915_trace.h"
struct clflush {
struct dma_fence_work base;
struct drm_i915_gem_object *obj;
static void __do_clflush(struct drm_i915_gem_object *obj)
i915_gem_object_flush_frontbuffer(obj, ORIGIN_CPU);
static int clflush_work(struct dma_fence_work *base)
struct clflush *clflush = container_of(base, typeof(*clflush), base);
struct drm_i915_gem_object *obj = clflush->obj;
int err;
err = i915_gem_object_pin_pages(obj);
if (err)
return err;
return 0;
static void clflush_release(struct dma_fence_work *base)
struct clflush *clflush = container_of(base, typeof(*clflush), base);
static const struct dma_fence_work_ops clflush_ops = {
.name = "clflush",
.work = clflush_work,
.release = clflush_release,
static struct clflush *clflush_work_create(struct drm_i915_gem_object *obj)
struct clflush *clflush;
clflush = kmalloc(sizeof(*clflush), GFP_KERNEL);
if (!clflush)
return NULL;
dma_fence_work_init(&clflush->base, &clflush_ops);
clflush->obj = i915_gem_object_get(obj); /* obj <-> clflush cycle */
return clflush;
bool i915_gem_clflush_object(struct drm_i915_gem_object *obj,
unsigned int flags)
struct clflush *clflush;
* Stolen memory is always coherent with the GPU as it is explicitly
* marked as wc by the system, or the system is cache-coherent.
* Similarly, we only access struct pages through the CPU cache, so
* anything not backed by physical memory we consider to be always
* coherent and not need clflushing.
if (!i915_gem_object_has_struct_page(obj)) {
obj->cache_dirty = false;
return false;
/* If the GPU is snooping the contents of the CPU cache,
* we do not need to manually clear the CPU cache lines. However,
* the caches are only snooped when the render cache is
* flushed/invalidated. As we always have to emit invalidations
* and flushes when moving into and out of the RENDER domain, correct
* snooping behaviour occurs naturally as the result of our domain
* tracking.
if (!(flags & I915_CLFLUSH_FORCE) &&
obj->cache_coherent & I915_BO_CACHE_COHERENT_FOR_READ)
return false;
clflush = NULL;
if (!(flags & I915_CLFLUSH_SYNC))
clflush = clflush_work_create(obj);
if (clflush) {
obj->base.resv, NULL, true,
dma_resv_add_excl_fence(obj->base.resv, &clflush->base.dma);
} else if (obj->mm.pages) {
} else {
GEM_BUG_ON(obj->write_domain != I915_GEM_DOMAIN_CPU);
obj->cache_dirty = false;
return true;