On Thu, Jan 20, 2022 at 1:48 PM Simon Ser contact@emersion.fr wrote:
Follow-up for the DRM_IOCTL_MODE_GETFB2 docs.
Signed-off-by: Simon Ser contact@emersion.fr Cc: Daniel Vetter daniel@ffwll.ch Cc: Pekka Paalanen pekka.paalanen@collabora.com Cc: Daniel Stone daniels@collabora.com
Thanks for pushing our docs forward!
Reviewed-by: Daniel Vetter daniel.vetter@ffwll.ch
include/uapi/drm/drm_mode.h | 83 ++++++++++++++++++++++++------------- 1 file changed, 55 insertions(+), 28 deletions(-)
diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h index e1e351682872..5dbbe1393bff 100644 --- a/include/uapi/drm/drm_mode.h +++ b/include/uapi/drm/drm_mode.h @@ -663,41 +663,68 @@ struct drm_mode_fb_cmd { #define DRM_MODE_FB_INTERLACED (1<<0) /* for interlaced framebuffers */ #define DRM_MODE_FB_MODIFIERS (1<<1) /* enables ->modifer[] */
+/**
- struct drm_mode_fb_cmd2 - Frame-buffer metadata.
- This struct holds frame-buffer metadata. There are two ways to use it:
- User-space can fill this struct and perform an &DRM_IOCTL_MODE_ADDFB2
- ioctl to register a new frame-buffer. The new frame-buffer object ID will
- be set by the kernel in @fb_id.
- User-space can set @fb_id and perform a &DRM_IOCTL_MODE_GETFB2 ioctl to
- fetch metadata about an existing frame-buffer.
- In case of planar formats, this struct allows up to 4 buffer objects with
- offsets and pitches per plane. The pitch and offset order is dictated by the
- fourcc, e.g. NV12 (https://fourcc.org/yuv.php#NV12) is described as:
YUV 4:2:0 image with a plane of 8 bit Y samples followed by an
interleaved U/V plane containing 8 bit 2x2 subsampled colour difference
samples.
- So it would consist of Y as ``offsets[0]`` and UV as ``offsets[1]``. Note
- that ``offsets[0]`` will generally be 0 (but this is not required).
- To accommodate tiled, compressed, etc formats, a modifier can be specified.
- For more information see the "Format Modifiers" section. Note that even
- though it looks like we have a modifier per-plane, we in fact do not. The
- modifier for each plane must be identical. Thus all combinations of
- different data layouts for multi-plane formats must be enumerated as
- separate modifiers.
- */
struct drm_mode_fb_cmd2 {
/** @fb_id: Object ID of the frame-buffer. */ __u32 fb_id;
/** @width: Width of the frame-buffer. */ __u32 width;
/** @height: Height of the frame-buffer. */ __u32 height;
__u32 pixel_format; /* fourcc code from drm_fourcc.h */
__u32 flags; /* see above flags */
/**
* @pixel_format: FourCC format code, see ``DRM_FORMAT_*`` constants in
* ``drm_fourcc.h``.
*/
__u32 pixel_format;
/**
* @flags: Frame-buffer flags (see &DRM_MODE_FB_INTERLACED and
* &DRM_MODE_FB_MODIFIERS).
*/
__u32 flags;
/*
* In case of planar formats, this ioctl allows up to 4
* buffer objects with offsets and pitches per plane.
* The pitch and offset order is dictated by the fourcc,
* e.g. NV12 (https://fourcc.org/yuv.php#NV12) is described as:
*
* YUV 4:2:0 image with a plane of 8 bit Y samples
* followed by an interleaved U/V plane containing
* 8 bit 2x2 subsampled colour difference samples.
*
* So it would consist of Y as offsets[0] and UV as
* offsets[1]. Note that offsets[0] will generally
* be 0 (but this is not required).
*
* To accommodate tiled, compressed, etc formats, a
* modifier can be specified. The default value of zero
* indicates "native" format as specified by the fourcc.
* Vendor specific modifier token. Note that even though
* it looks like we have a modifier per-plane, we in fact
* do not. The modifier for each plane must be identical.
* Thus all combinations of different data layouts for
* multi plane formats must be enumerated as separate
* modifiers.
/**
* @handles: GEM buffer handle, one per plane. Set to 0 if the plane is
* unused. */ __u32 handles[4];
__u32 pitches[4]; /* pitch for each plane */
__u32 offsets[4]; /* offset of each plane */
__u64 modifier[4]; /* ie, tiling, compress */
/** @pitches: Pitch (aka. stride), one per plane. */
__u32 pitches[4];
/** @offsets: Offset into the buffer, one per plane. */
__u32 offsets[4];
/**
* @modifier: Format modifier, one per plane. See ``DRM_FORMAT_MOD_*``
* constants in ``drm_fourcc.h``. All planes must use the same
* modifier. Ignored unless &DRM_MODE_FB_MODIFIERS is set in @flags.
*/
__u64 modifier[4];
};
#define DRM_MODE_FB_DIRTY_ANNOTATE_COPY 0x01
base-commit: 37e0321ab2569b44f8a94339bf47653493ac864e
2.34.1