diff options
Diffstat (limited to 'drivers/gpu/drm/i915/gem/i915_gem_clflush.c')
-rw-r--r-- | drivers/gpu/drm/i915/gem/i915_gem_clflush.c | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_clflush.c b/drivers/gpu/drm/i915/gem/i915_gem_clflush.c new file mode 100644 index 000000000000..5295285d5843 --- /dev/null +++ b/drivers/gpu/drm/i915/gem/i915_gem_clflush.c @@ -0,0 +1,162 @@ +/* + * SPDX-License-Identifier: MIT + * + * Copyright © 2016 Intel Corporation + */ + +#include "display/intel_frontbuffer.h" + +#include "i915_drv.h" +#include "i915_gem_clflush.h" + +static DEFINE_SPINLOCK(clflush_lock); + +struct clflush { + struct dma_fence dma; /* Must be first for dma_fence_free() */ + struct i915_sw_fence wait; + struct work_struct work; + struct drm_i915_gem_object *obj; +}; + +static const char *i915_clflush_get_driver_name(struct dma_fence *fence) +{ + return DRIVER_NAME; +} + +static const char *i915_clflush_get_timeline_name(struct dma_fence *fence) +{ + return "clflush"; +} + +static void i915_clflush_release(struct dma_fence *fence) +{ + struct clflush *clflush = container_of(fence, typeof(*clflush), dma); + + i915_sw_fence_fini(&clflush->wait); + + BUILD_BUG_ON(offsetof(typeof(*clflush), dma)); + dma_fence_free(&clflush->dma); +} + +static const struct dma_fence_ops i915_clflush_ops = { + .get_driver_name = i915_clflush_get_driver_name, + .get_timeline_name = i915_clflush_get_timeline_name, + .release = i915_clflush_release, +}; + +static void __i915_do_clflush(struct drm_i915_gem_object *obj) +{ + GEM_BUG_ON(!i915_gem_object_has_pages(obj)); + drm_clflush_sg(obj->mm.pages); + intel_fb_obj_flush(obj, ORIGIN_CPU); +} + +static void i915_clflush_work(struct work_struct *work) +{ + struct clflush *clflush = container_of(work, typeof(*clflush), work); + struct drm_i915_gem_object *obj = clflush->obj; + + if (i915_gem_object_pin_pages(obj)) { + DRM_ERROR("Failed to acquire obj->pages for clflushing\n"); + goto out; + } + + __i915_do_clflush(obj); + + i915_gem_object_unpin_pages(obj); + +out: + i915_gem_object_put(obj); + + dma_fence_signal(&clflush->dma); + dma_fence_put(&clflush->dma); +} + +static int __i915_sw_fence_call +i915_clflush_notify(struct i915_sw_fence *fence, + enum i915_sw_fence_notify state) +{ + struct clflush *clflush = container_of(fence, typeof(*clflush), wait); + + switch (state) { + case FENCE_COMPLETE: + schedule_work(&clflush->work); + break; + + case FENCE_FREE: + dma_fence_put(&clflush->dma); + break; + } + + return NOTIFY_DONE; +} + +bool i915_gem_clflush_object(struct drm_i915_gem_object *obj, + unsigned int flags) +{ + struct clflush *clflush; + + assert_object_held(obj); + + /* + * 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; + + trace_i915_gem_object_clflush(obj); + + clflush = NULL; + if (!(flags & I915_CLFLUSH_SYNC)) + clflush = kmalloc(sizeof(*clflush), GFP_KERNEL); + if (clflush) { + GEM_BUG_ON(!obj->cache_dirty); + + dma_fence_init(&clflush->dma, + &i915_clflush_ops, + &clflush_lock, + to_i915(obj->base.dev)->mm.unordered_timeline, + 0); + i915_sw_fence_init(&clflush->wait, i915_clflush_notify); + + clflush->obj = i915_gem_object_get(obj); + INIT_WORK(&clflush->work, i915_clflush_work); + + dma_fence_get(&clflush->dma); + + i915_sw_fence_await_reservation(&clflush->wait, + obj->base.resv, NULL, + true, I915_FENCE_TIMEOUT, + I915_FENCE_GFP); + + reservation_object_add_excl_fence(obj->base.resv, + &clflush->dma); + + i915_sw_fence_commit(&clflush->wait); + } else if (obj->mm.pages) { + __i915_do_clflush(obj); + } else { + GEM_BUG_ON(obj->write_domain != I915_GEM_DOMAIN_CPU); + } + + obj->cache_dirty = false; + return true; +} |