diff options
Diffstat (limited to 'include/uapi/drm/i915_drm.h')
| -rw-r--r-- | include/uapi/drm/i915_drm.h | 29 |
1 files changed, 28 insertions, 1 deletions
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h index 57093b455db6..6620b6ad76ed 100644 --- a/include/uapi/drm/i915_drm.h +++ b/include/uapi/drm/i915_drm.h @@ -397,6 +397,12 @@ typedef struct drm_i915_irq_wait { #define I915_PARAM_HAS_SCHEDULER 41 #define I915_PARAM_HUC_STATUS 42 +/* Query whether DRM_I915_GEM_EXECBUFFER2 supports the ability to opt-out of + * synchronisation with implicit fencing on individual objects. + * See EXEC_OBJECT_ASYNC. + */ +#define I915_PARAM_HAS_EXEC_ASYNC 43 + typedef struct drm_i915_getparam { __s32 param; /* @@ -737,8 +743,29 @@ struct drm_i915_gem_exec_object2 { #define EXEC_OBJECT_SUPPORTS_48B_ADDRESS (1<<3) #define EXEC_OBJECT_PINNED (1<<4) #define EXEC_OBJECT_PAD_TO_SIZE (1<<5) +/* The kernel implicitly tracks GPU activity on all GEM objects, and + * synchronises operations with outstanding rendering. This includes + * rendering on other devices if exported via dma-buf. However, sometimes + * this tracking is too coarse and the user knows better. For example, + * if the object is split into non-overlapping ranges shared between different + * clients or engines (i.e. suballocating objects), the implicit tracking + * by kernel assumes that each operation affects the whole object rather + * than an individual range, causing needless synchronisation between clients. + * The kernel will also forgo any CPU cache flushes prior to rendering from + * the object as the client is expected to be also handling such domain + * tracking. + * + * The kernel maintains the implicit tracking in order to manage resources + * used by the GPU - this flag only disables the synchronisation prior to + * rendering with this object in this execbuf. + * + * Opting out of implicit synhronisation requires the user to do its own + * explicit tracking to avoid rendering corruption. See, for example, + * I915_PARAM_HAS_EXEC_FENCE to order execbufs and execute them asynchronously. + */ +#define EXEC_OBJECT_ASYNC (1<<6) /* All remaining bits are MBZ and RESERVED FOR FUTURE USE */ -#define __EXEC_OBJECT_UNKNOWN_FLAGS -(EXEC_OBJECT_PAD_TO_SIZE<<1) +#define __EXEC_OBJECT_UNKNOWN_FLAGS -(EXEC_OBJECT_ASYNC<<1) __u64 flags; union { |