diff options
Diffstat (limited to 'include/uapi/drm')
| -rw-r--r-- | include/uapi/drm/i915_drm.h | 47 |
1 files changed, 36 insertions, 11 deletions
diff --git a/include/uapi/drm/i915_drm.h b/include/uapi/drm/i915_drm.h index e20eeeca7a1c..0aea82657cdc 100644 --- a/include/uapi/drm/i915_drm.h +++ b/include/uapi/drm/i915_drm.h @@ -849,31 +849,56 @@ struct drm_i915_gem_mmap_gtt { __u64 offset; }; +/** + * struct drm_i915_gem_mmap_offset - Retrieve an offset so we can mmap this buffer object. + * + * This struct is passed as argument to the `DRM_IOCTL_I915_GEM_MMAP_OFFSET` ioctl, + * and is used to retrieve the fake offset to mmap an object specified by &handle. + * + * The legacy way of using `DRM_IOCTL_I915_GEM_MMAP` is removed on gen12+. + * `DRM_IOCTL_I915_GEM_MMAP_GTT` is an older supported alias to this struct, but will behave + * as setting the &extensions to 0, and &flags to `I915_MMAP_OFFSET_GTT`. + */ struct drm_i915_gem_mmap_offset { - /** Handle for the object being mapped. */ + /** @handle: Handle for the object being mapped. */ __u32 handle; + /** @pad: Must be zero */ __u32 pad; /** - * Fake offset to use for subsequent mmap call + * @offset: The fake offset to use for subsequent mmap call * * This is a fixed-size type for 32/64 compatibility. */ __u64 offset; /** - * Flags for extended behaviour. + * @flags: Flags for extended behaviour. * - * It is mandatory that one of the MMAP_OFFSET types - * (GTT, WC, WB, UC, etc) should be included. + * It is mandatory that one of the `MMAP_OFFSET` types + * should be included: + * + * - `I915_MMAP_OFFSET_GTT`: Use mmap with the object bound to GTT. (Write-Combined) + * - `I915_MMAP_OFFSET_WC`: Use Write-Combined caching. + * - `I915_MMAP_OFFSET_WB`: Use Write-Back caching. + * - `I915_MMAP_OFFSET_FIXED`: Use object placement to determine caching. + * + * On devices with local memory `I915_MMAP_OFFSET_FIXED` is the only valid + * type. On devices without local memory, this caching mode is invalid. + * + * As caching mode when specifying `I915_MMAP_OFFSET_FIXED`, WC or WB will + * be used, depending on the object placement on creation. WB will be used + * when the object can only exist in system memory, WC otherwise. */ __u64 flags; -#define I915_MMAP_OFFSET_GTT 0 -#define I915_MMAP_OFFSET_WC 1 -#define I915_MMAP_OFFSET_WB 2 -#define I915_MMAP_OFFSET_UC 3 - /* - * Zero-terminated chain of extensions. +#define I915_MMAP_OFFSET_GTT 0 +#define I915_MMAP_OFFSET_WC 1 +#define I915_MMAP_OFFSET_WB 2 +#define I915_MMAP_OFFSET_UC 3 +#define I915_MMAP_OFFSET_FIXED 4 + + /** + * @extensions: Zero-terminated chain of extensions. * * No current extensions defined; mbz. */ |