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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/gpu/drm/i915/gem/i915_gem_clflush.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/gpu/drm/i915/gem/i915_gem_clflush.c')
-rw-r--r--drivers/gpu/drm/i915/gem/i915_gem_clflush.c139
1 files changed, 139 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 0000000000..385ffc575b
--- /dev/null
+++ b/drivers/gpu/drm/i915/gem/i915_gem_clflush.c
@@ -0,0 +1,139 @@
+/*
+ * SPDX-License-Identifier: MIT
+ *
+ * Copyright © 2016 Intel Corporation
+ */
+
+#include <drm/drm_cache.h>
+
+#include "display/intel_frontbuffer.h"
+
+#include "i915_config.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)
+{
+ GEM_BUG_ON(!i915_gem_object_has_pages(obj));
+ drm_clflush_sg(obj->mm.pages);
+
+ i915_gem_object_flush_frontbuffer(obj, ORIGIN_CPU);
+}
+
+static void clflush_work(struct dma_fence_work *base)
+{
+ struct clflush *clflush = container_of(base, typeof(*clflush), base);
+
+ __do_clflush(clflush->obj);
+}
+
+static void clflush_release(struct dma_fence_work *base)
+{
+ struct clflush *clflush = container_of(base, typeof(*clflush), base);
+
+ i915_gem_object_unpin_pages(clflush->obj);
+ i915_gem_object_put(clflush->obj);
+}
+
+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;
+
+ GEM_BUG_ON(!obj->cache_dirty);
+
+ clflush = kmalloc(sizeof(*clflush), GFP_KERNEL);
+ if (!clflush)
+ return NULL;
+
+ if (__i915_gem_object_get_pages(obj) < 0) {
+ kfree(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 drm_i915_private *i915 = to_i915(obj->base.dev);
+ struct clflush *clflush;
+
+ assert_object_held(obj);
+
+ if (IS_DGFX(i915)) {
+ WARN_ON_ONCE(obj->cache_dirty);
+ return false;
+ }
+
+ /*
+ * 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) &&
+ dma_resv_reserve_fences(obj->base.resv, 1) == 0)
+ clflush = clflush_work_create(obj);
+ if (clflush) {
+ i915_sw_fence_await_reservation(&clflush->base.chain,
+ obj->base.resv, true,
+ i915_fence_timeout(i915),
+ I915_FENCE_GFP);
+ dma_resv_add_fence(obj->base.resv, &clflush->base.dma,
+ DMA_RESV_USAGE_KERNEL);
+ dma_fence_work_commit(&clflush->base);
+ /*
+ * We must have successfully populated the pages(since we are
+ * holding a pin on the pages as per the flush worker) to reach
+ * this point, which must mean we have already done the required
+ * flush-on-acquire, hence resetting cache_dirty here should be
+ * safe.
+ */
+ obj->cache_dirty = false;
+ } else if (obj->mm.pages) {
+ __do_clflush(obj);
+ obj->cache_dirty = false;
+ } else {
+ GEM_BUG_ON(obj->write_domain != I915_GEM_DOMAIN_CPU);
+ }
+
+ return true;
+}