diff options
Diffstat (limited to 'include/uapi/drm/i915_drm.h')
-rw-r--r-- | include/uapi/drm/i915_drm.h | 43 |
1 files changed, 35 insertions, 8 deletions
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h index acf2102..a5524cc 100644 --- a/include/uapi/drm/i915_drm.h +++ b/include/uapi/drm/i915_drm.h @@ -772,10 +772,12 @@ struct drm_i915_gem_execbuffer2 { #define I915_EXEC_HANDLE_LUT (1<<12) /** Used for switching BSD rings on the platforms with two BSD rings */ -#define I915_EXEC_BSD_MASK (3<<13) -#define I915_EXEC_BSD_DEFAULT (0<<13) /* default ping-pong mode */ -#define I915_EXEC_BSD_RING1 (1<<13) -#define I915_EXEC_BSD_RING2 (2<<13) +#define I915_EXEC_BSD_SHIFT (13) +#define I915_EXEC_BSD_MASK (3 << I915_EXEC_BSD_SHIFT) +/* default ping-pong mode */ +#define I915_EXEC_BSD_DEFAULT (0 << I915_EXEC_BSD_SHIFT) +#define I915_EXEC_BSD_RING1 (1 << I915_EXEC_BSD_SHIFT) +#define I915_EXEC_BSD_RING2 (2 << I915_EXEC_BSD_SHIFT) /** Tell the kernel that the batchbuffer is processed by * the resource streamer. @@ -812,10 +814,35 @@ struct drm_i915_gem_busy { /** Handle of the buffer to check for busy */ __u32 handle; - /** Return busy status (1 if busy, 0 if idle). - * The high word is used to indicate on which rings the object - * currently resides: - * 16:31 - busy (r or r/w) rings (16 render, 17 bsd, 18 blt, etc) + /** Return busy status + * + * A return of 0 implies that the object is idle (after + * having flushed any pending activity), and a non-zero return that + * the object is still in-flight on the GPU. (The GPU has not yet + * signaled completion for all pending requests that reference the + * object.) + * + * The returned dword is split into two fields to indicate both + * the engines on which the object is being read, and the + * engine on which it is currently being written (if any). + * + * The low word (bits 0:15) indicate if the object is being written + * to by any engine (there can only be one, as the GEM implicit + * synchronisation rules force writes to be serialised). Only the + * engine for the last write is reported. + * + * The high word (bits 16:31) are a bitmask of which engines are + * currently reading from the object. Multiple engines may be + * reading from the object simultaneously. + * + * The value of each engine is the same as specified in the + * EXECBUFFER2 ioctl, i.e. I915_EXEC_RENDER, I915_EXEC_BSD etc. + * Note I915_EXEC_DEFAULT is a symbolic value and is mapped to + * the I915_EXEC_RENDER engine for execution, and so it is never + * reported as active itself. Some hardware may have parallel + * execution engines, e.g. multiple media engines, which are + * mapped to the same identifier in the EXECBUFFER2 ioctl and + * so are not separately reported for busyness. */ __u32 busy; }; |