diff options
Diffstat (limited to 'drivers/gpu/drm/i915/i915_vma.h')
| -rw-r--r-- | drivers/gpu/drm/i915/i915_vma.h | 45 |
1 files changed, 29 insertions, 16 deletions
diff --git a/drivers/gpu/drm/i915/i915_vma.h b/drivers/gpu/drm/i915/i915_vma.h index 7252abc73d3e..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; |