All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH 1/2] drm/i915: Combine write_domain flushes to a single function
@ 2017-04-11 13:47 Chris Wilson
  2017-04-11 13:47 ` [PATCH 2/2] drm/i915: Treat WC a separate cache domain Chris Wilson
                   ` (4 more replies)
  0 siblings, 5 replies; 8+ messages in thread
From: Chris Wilson @ 2017-04-11 13:47 UTC (permalink / raw)
  To: intel-gfx

In the next patch, we will introduce a new cache domain for
differentiating between GTT access and direct WC access. This will
require us to include WC in our write_domain flushes. Rather than
duplicate a third function, combine the existing two into one and
flushing WC writes will then be automatically handled as well.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_gem.c                    | 123 ++++++++++-----------
 .../gpu/drm/i915/selftests/i915_gem_coherency.c    |   4 +-
 drivers/gpu/drm/i915/selftests/i915_gem_object.c   |   2 +-
 3 files changed, 63 insertions(+), 66 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index cb8c6a94ba4e..354082df10c4 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -46,8 +46,6 @@
 #include <linux/dma-buf.h>
 
 static void i915_gem_flush_free_objects(struct drm_i915_private *i915);
-static void i915_gem_object_flush_gtt_write_domain(struct drm_i915_gem_object *obj);
-static void i915_gem_object_flush_cpu_write_domain(struct drm_i915_gem_object *obj);
 
 static bool cpu_write_needs_clflush(struct drm_i915_gem_object *obj)
 {
@@ -705,6 +703,62 @@ i915_gem_create_ioctl(struct drm_device *dev, void *data,
 			       args->size, &args->handle);
 }
 
+static inline enum fb_op_origin
+write_origin(struct drm_i915_gem_object *obj, unsigned int domain)
+{
+	return (domain == I915_GEM_DOMAIN_GTT ?
+		obj->frontbuffer_ggtt_origin : ORIGIN_CPU);
+}
+
+static void
+flush_write_domain(struct drm_i915_gem_object *obj,
+		   unsigned int exclude_write_domain)
+{
+	struct drm_i915_private *dev_priv = to_i915(obj->base.dev);
+
+	if (!obj->base.write_domain ||
+	    obj->base.write_domain == exclude_write_domain)
+		return;
+
+	/* No actual flushing is required for the GTT write domain.  Writes
+	 * to it "immediately" go to main memory as far as we know, so there's
+	 * no chipset flush.  It also doesn't land in render cache.
+	 *
+	 * However, we do have to enforce the order so that all writes through
+	 * the GTT land before any writes to the device, such as updates to
+	 * the GATT itself.
+	 *
+	 * We also have to wait a bit for the writes to land from the GTT.
+	 * An uncached read (i.e. mmio) seems to be ideal for the round-trip
+	 * timing. This issue has only been observed when switching quickly
+	 * between GTT writes and CPU reads from inside the kernel on recent hw,
+	 * and it appears to only affect discrete GTT blocks (i.e. on LLC
+	 * system agents we cannot reproduce this behaviour).
+	 */
+	wmb();
+
+	switch (obj->base.write_domain) {
+	case I915_GEM_DOMAIN_GTT:
+		if (INTEL_GEN(dev_priv) >= 6 && !HAS_LLC(dev_priv)) {
+			if (intel_runtime_pm_get_if_in_use(dev_priv)) {
+				spin_lock_irq(&dev_priv->uncore.lock);
+				POSTING_READ_FW(RING_ACTHD(dev_priv->engine[RCS]->mmio_base));
+				spin_unlock_irq(&dev_priv->uncore.lock);
+				intel_runtime_pm_put(dev_priv);
+			}
+		}
+
+		intel_fb_obj_flush(obj, write_origin(obj, I915_GEM_DOMAIN_GTT));
+		break;
+
+	case I915_GEM_DOMAIN_CPU:
+		i915_gem_clflush_object(obj, I915_CLFLUSH_SYNC);
+		break;
+	}
+
+	obj->base.write_domain = 0;
+}
+
 static inline int
 __copy_to_user_swizzled(char __user *cpu_vaddr,
 			const char *gpu_vaddr, int gpu_offset,
@@ -794,7 +848,7 @@ int i915_gem_obj_prepare_shmem_read(struct drm_i915_gem_object *obj,
 			goto out;
 	}
 
-	i915_gem_object_flush_gtt_write_domain(obj);
+	flush_write_domain(obj, I915_GEM_DOMAIN_CPU);
 
 	/* If we're not in the cpu read domain, set ourself into the gtt
 	 * read domain and manually flush cachelines (if required). This
@@ -846,7 +900,7 @@ int i915_gem_obj_prepare_shmem_write(struct drm_i915_gem_object *obj,
 			goto out;
 	}
 
-	i915_gem_object_flush_gtt_write_domain(obj);
+	flush_write_domain(obj, I915_GEM_DOMAIN_CPU);
 
 	/* If we're not in the cpu write domain, set ourself into the
 	 * gtt write domain and manually flush cachelines (as required).
@@ -1501,13 +1555,6 @@ i915_gem_pwrite_ioctl(struct drm_device *dev, void *data,
 	return ret;
 }
 
-static inline enum fb_op_origin
-write_origin(struct drm_i915_gem_object *obj, unsigned domain)
-{
-	return (domain == I915_GEM_DOMAIN_GTT ?
-		obj->frontbuffer_ggtt_origin : ORIGIN_CPU);
-}
-
 static void i915_gem_object_bump_inactive_ggtt(struct drm_i915_gem_object *obj)
 {
 	struct drm_i915_private *i915;
@@ -3320,56 +3367,6 @@ int i915_gem_wait_for_idle(struct drm_i915_private *i915, unsigned int flags)
 	return ret;
 }
 
-/** Flushes the GTT write domain for the object if it's dirty. */
-static void
-i915_gem_object_flush_gtt_write_domain(struct drm_i915_gem_object *obj)
-{
-	struct drm_i915_private *dev_priv = to_i915(obj->base.dev);
-
-	if (obj->base.write_domain != I915_GEM_DOMAIN_GTT)
-		return;
-
-	/* No actual flushing is required for the GTT write domain.  Writes
-	 * to it "immediately" go to main memory as far as we know, so there's
-	 * no chipset flush.  It also doesn't land in render cache.
-	 *
-	 * However, we do have to enforce the order so that all writes through
-	 * the GTT land before any writes to the device, such as updates to
-	 * the GATT itself.
-	 *
-	 * We also have to wait a bit for the writes to land from the GTT.
-	 * An uncached read (i.e. mmio) seems to be ideal for the round-trip
-	 * timing. This issue has only been observed when switching quickly
-	 * between GTT writes and CPU reads from inside the kernel on recent hw,
-	 * and it appears to only affect discrete GTT blocks (i.e. on LLC
-	 * system agents we cannot reproduce this behaviour).
-	 */
-	wmb();
-	if (INTEL_GEN(dev_priv) >= 6 && !HAS_LLC(dev_priv)) {
-		if (intel_runtime_pm_get_if_in_use(dev_priv)) {
-			spin_lock_irq(&dev_priv->uncore.lock);
-			POSTING_READ_FW(RING_ACTHD(dev_priv->engine[RCS]->mmio_base));
-			spin_unlock_irq(&dev_priv->uncore.lock);
-			intel_runtime_pm_put(dev_priv);
-		}
-	}
-
-	intel_fb_obj_flush(obj, write_origin(obj, I915_GEM_DOMAIN_GTT));
-
-	obj->base.write_domain = 0;
-}
-
-/** Flushes the CPU write domain for the object if it's dirty. */
-static void
-i915_gem_object_flush_cpu_write_domain(struct drm_i915_gem_object *obj)
-{
-	if (obj->base.write_domain != I915_GEM_DOMAIN_CPU)
-		return;
-
-	i915_gem_clflush_object(obj, I915_CLFLUSH_SYNC);
-	obj->base.write_domain = 0;
-}
-
 static void __i915_gem_object_flush_for_display(struct drm_i915_gem_object *obj)
 {
 	if (obj->base.write_domain != I915_GEM_DOMAIN_CPU && !obj->cache_dirty)
@@ -3428,7 +3425,7 @@ i915_gem_object_set_to_gtt_domain(struct drm_i915_gem_object *obj, bool write)
 	if (ret)
 		return ret;
 
-	i915_gem_object_flush_cpu_write_domain(obj);
+	flush_write_domain(obj, I915_GEM_DOMAIN_GTT);
 
 	/* Serialise direct access to this object with the barriers for
 	 * coherent writes from the GPU, by effectively invalidating the
@@ -3802,7 +3799,7 @@ i915_gem_object_set_to_cpu_domain(struct drm_i915_gem_object *obj, bool write)
 	if (obj->base.write_domain == I915_GEM_DOMAIN_CPU)
 		return 0;
 
-	i915_gem_object_flush_gtt_write_domain(obj);
+	flush_write_domain(obj, I915_GEM_DOMAIN_CPU);
 
 	/* Flush the CPU cache if it's still invalid. */
 	if ((obj->base.read_domains & I915_GEM_DOMAIN_CPU) == 0) {
diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_coherency.c b/drivers/gpu/drm/i915/selftests/i915_gem_coherency.c
index f08d0179b3df..615fb75f3ed7 100644
--- a/drivers/gpu/drm/i915/selftests/i915_gem_coherency.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem_coherency.c
@@ -139,7 +139,7 @@ static int wc_set(struct drm_i915_gem_object *obj,
 	int err;
 
 	/* XXX GTT write followed by WC write go missing */
-	i915_gem_object_flush_gtt_write_domain(obj);
+	flush_write_domain(obj, 0);
 
 	err = i915_gem_object_set_to_gtt_domain(obj, true);
 	if (err)
@@ -163,7 +163,7 @@ static int wc_get(struct drm_i915_gem_object *obj,
 	int err;
 
 	/* XXX WC write followed by GTT write go missing */
-	i915_gem_object_flush_gtt_write_domain(obj);
+	flush_write_domain(obj, 0);
 
 	err = i915_gem_object_set_to_gtt_domain(obj, false);
 	if (err)
diff --git a/drivers/gpu/drm/i915/selftests/i915_gem_object.c b/drivers/gpu/drm/i915/selftests/i915_gem_object.c
index 67d82bf1407f..f6246b71f301 100644
--- a/drivers/gpu/drm/i915/selftests/i915_gem_object.c
+++ b/drivers/gpu/drm/i915/selftests/i915_gem_object.c
@@ -266,7 +266,7 @@ static int check_partial_mapping(struct drm_i915_gem_object *obj,
 		if (offset >= obj->base.size)
 			continue;
 
-		i915_gem_object_flush_gtt_write_domain(obj);
+		flush_write_domain(obj, I915_GEM_DOMAIN_CPU);
 
 		p = i915_gem_object_get_page(obj, offset >> PAGE_SHIFT);
 		cpu = kmap(p) + offset_in_page(offset);
-- 
2.11.0

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 8+ messages in thread

end of thread, other threads:[~2017-04-12 10:31 UTC | newest]

Thread overview: 8+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2017-04-11 13:47 [PATCH 1/2] drm/i915: Combine write_domain flushes to a single function Chris Wilson
2017-04-11 13:47 ` [PATCH 2/2] drm/i915: Treat WC a separate cache domain Chris Wilson
2017-04-11 15:12 ` ✓ Fi.CI.BAT: success for series starting with [1/2] drm/i915: Combine write_domain flushes to a single function Patchwork
2017-04-12  8:42 ` [PATCH 1/2] " Joonas Lahtinen
2017-04-12  9:42 ` [PATCH v2] " Chris Wilson
2017-04-12 10:06   ` Joonas Lahtinen
2017-04-12 10:23     ` Chris Wilson
2017-04-12 10:31 ` ✗ Fi.CI.BAT: failure for series starting with [v2] drm/i915: Combine write_domain flushes to a single function (rev2) Patchwork

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.