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Diffstat (limited to 'drivers/gpu/drm/i915/i915_vma.h')
-rw-r--r--drivers/gpu/drm/i915/i915_vma.h47
1 files changed, 30 insertions, 17 deletions
diff --git a/drivers/gpu/drm/i915/i915_vma.h b/drivers/gpu/drm/i915/i915_vma.h
index 4f7c1c7599f4..5793abe509a2 100644
--- a/drivers/gpu/drm/i915/i915_vma.h
+++ b/drivers/gpu/drm/i915/i915_vma.h
@@ -71,29 +71,42 @@ struct i915_vma {
unsigned int open_count;
unsigned long flags;
/**
- * How many users have pinned this object in GTT space. The following
- * users can each hold at most one reference: pwrite/pread, execbuffer
- * (objects are not allowed multiple times for the same batchbuffer),
- * and the framebuffer code. When switching/pageflipping, the
- * framebuffer code has at most two buffers pinned per crtc.
+ * How many users have pinned this object in GTT space.
*
- * In the worst case this is 1 + 1 + 1 + 2*2 = 7. That would fit into 3
- * bits with absolutely no headroom. So use 4 bits.
+ * This is a tightly bound, fairly small number of users, so we
+ * stuff inside the flags field so that we can both check for overflow
+ * and detect a no-op i915_vma_pin() in a single check, while also
+ * pinning the vma.
+ *
+ * The worst case display setup would have the same vma pinned for
+ * use on each plane on each crtc, while also building the next atomic
+ * state and holding a pin for the length of the cleanup queue. In the
+ * future, the flip queue may be increased from 1.
+ * Estimated worst case: 3 [qlen] * 4 [max crtcs] * 7 [max planes] = 84
+ *
+ * For GEM, the number of concurrent users for pwrite/pread is
+ * unbounded. For execbuffer, it is currently one but will in future
+ * be extended to allow multiple clients to pin vma concurrently.
+ *
+ * We also use suballocated pages, with each suballocation claiming
+ * its own pin on the shared vma. At present, this is limited to
+ * exclusive cachelines of a single page, so a maximum of 64 possible
+ * users.
*/
-#define I915_VMA_PIN_MASK 0xf
-#define I915_VMA_PIN_OVERFLOW BIT(5)
+#define I915_VMA_PIN_MASK 0xff
+#define I915_VMA_PIN_OVERFLOW BIT(8)
/** Flags and address space this VMA is bound to */
-#define I915_VMA_GLOBAL_BIND BIT(6)
-#define I915_VMA_LOCAL_BIND BIT(7)
+#define I915_VMA_GLOBAL_BIND BIT(9)
+#define I915_VMA_LOCAL_BIND BIT(10)
#define I915_VMA_BIND_MASK (I915_VMA_GLOBAL_BIND | I915_VMA_LOCAL_BIND | I915_VMA_PIN_OVERFLOW)
-#define I915_VMA_GGTT BIT(8)
-#define I915_VMA_CAN_FENCE BIT(9)
-#define I915_VMA_CLOSED BIT(10)
-#define I915_VMA_USERFAULT_BIT 11
+#define I915_VMA_GGTT BIT(11)
+#define I915_VMA_CAN_FENCE BIT(12)
+#define I915_VMA_CLOSED BIT(13)
+#define I915_VMA_USERFAULT_BIT 14
#define I915_VMA_USERFAULT BIT(I915_VMA_USERFAULT_BIT)
-#define I915_VMA_GGTT_WRITE BIT(12)
+#define I915_VMA_GGTT_WRITE BIT(15)
unsigned int active_count;
struct rb_root active;
@@ -425,7 +438,7 @@ void i915_vma_parked(struct drm_i915_private *i915);
* or the list is empty ofc.
*/
#define for_each_ggtt_vma(V, OBJ) \
- list_for_each_entry(V, &(OBJ)->vma_list, obj_link) \
+ list_for_each_entry(V, &(OBJ)->vma.list, obj_link) \
for_each_until(!i915_vma_is_ggtt(V))
#endif
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