On Friday, March 5th, 2021 at 9:28 AM, Pekka Paalanen <ppaalanen@xxxxxxxxx> wrote: > > +/** > > + * DRM_CAP_DUMB_PREFERRED_DEPTH > > + * > > + * The preferred depth (in bits) for dumb buffers. > > this is literally depth, not bits per pixel, right? "Depth" is pretty ambiguous [1]. Maybe we should be more explicit here and say that it's the number of bits used to indicate the color of a single pixel? And maybe add a note that it's different from bits per pixel? [1]: https://en.wikipedia.org/wiki/Color_depth > > + */ > > #define DRM_CAP_DUMB_PREFERRED_DEPTH 0x3 > > +/** > > + * DRM_CAP_DUMB_PREFER_SHADOW > > + * > > + * If set to 1, the driver prefers userspace to render to a shadow buffer > > + * instead of directly rendering to a dumb buffer. > > Maybe add something like: > > For best speed, userspace should do streaming ordered memory copies > into the dumb buffer and never read from it. > > Isn't that correct? Good call, will add. > > + */ > > #define DRM_CAP_DUMB_PREFER_SHADOW 0x4 > > +/** > > + * DRM_CAP_PRIME > > + * > > + * Bitfield of supported PRIME sharing capabilities. See &DRM_PRIME_CAP_IMPORT > > + * and &DRM_PRIME_CAP_EXPORT. > > + */ > > #define DRM_CAP_PRIME 0x5 > > +/** > > + * DRM_PRIME_CAP_IMPORT > > + * > > + * If this bit is set in &DRM_CAP_PRIME, the driver supports importing PRIME > > + * buffers. > > What are PRIME buffers? Will add something like: PRIME buffers are exposed as dma-buf file descriptors. See Documentation/gpu/drm-mm.rst, section "PRIME Buffer Sharing". > > + */ > > #define DRM_PRIME_CAP_IMPORT 0x1 > > +/** > > + * DRM_PRIME_CAP_EXPORT > > + * > > + * If this bit is set in &DRM_CAP_PRIME, the driver supports exporting PRIME > > + * buffers. > > What's the export API? HandleToFD()? Yes. Will add a note about it. Same for import. > > + */ > > #define DRM_PRIME_CAP_EXPORT 0x2 > > +/** > > + * DRM_CAP_TIMESTAMP_MONOTONIC > > + * > > + * If set to 0, the kernel will report timestamps with the realtime clock in > > + * struct drm_event_vblank. If set to 1, the kernel will report timestamps with > > + * the monotonic clock. > > I think it would be more explicit to say CLOCK_REALTIME and > CLOCK_MONOTONIC, because there are things like CLOCK_MONOTONIC_RAW > which is different. Mention clock_gettime()? Ack, better be explicit here. > > + */ > > #define DRM_CAP_TIMESTAMP_MONOTONIC 0x6 > > +/** > > + * DRM_CAP_ASYNC_PAGE_FLIP > > + * > > + * If set to 1, the driver supports &DRM_MODE_PAGE_FLIP_ASYNC. > > Does this apply equally to both legacy and atomic KMS API? Yes (it's included in DRM_MODE_ATOMIC_FLAGS), but I heard that some drivers get it wrong. > > + */ > > #define DRM_CAP_ASYNC_PAGE_FLIP 0x7 > > -/* > > - * The CURSOR_WIDTH and CURSOR_HEIGHT capabilities return a valid widthxheight > > - * combination for the hardware cursor. The intention is that a hardware > > - * agnostic userspace can query a cursor plane size to use. > > +/** > > + * DRM_CAP_CURSOR_WIDTH > > + * > > + * The ``CURSOR_WIDTH`` and ``CURSOR_HEIGHT`` capabilities return a valid > > + * width x height combination for the hardware cursor. The intention is that a > > + * hardware agnostic userspace can query a cursor plane size to use. > > * > > * Note that the cross-driver contract is to merely return a valid size; > > * drivers are free to attach another meaning on top, eg. i915 returns the > > * maximum plane size. > > */ > > #define DRM_CAP_CURSOR_WIDTH 0x8 > > +/** > > + * DRM_CAP_CURSOR_HEIGHT > > + * > > + * See &DRM_CAP_CURSOR_WIDTH. > > + */ > > #define DRM_CAP_CURSOR_HEIGHT 0x9 > > +/** > > + * DRM_CAP_ADDFB2_MODIFIERS > > + * > > + * If set to 1, the driver supports supplying modifiers in the > > + * &DRM_IOCTL_MODE_ADDFB2 ioctl. > > + */ > > #define DRM_CAP_ADDFB2_MODIFIERS 0x10 > > +/** > > + * DRM_CAP_PAGE_FLIP_TARGET > > + * > > + * If set to 1, the driver supports the &DRM_MODE_PAGE_FLIP_TARGET_ABSOLUTE and > > + * &DRM_MODE_PAGE_FLIP_TARGET_RELATIVE flags in > > + * &drm_mode_crtc_page_flip_target.flags for the &DRM_IOCTL_MODE_PAGE_FLIP > > + * ioctl. > > + */ > > #define DRM_CAP_PAGE_FLIP_TARGET 0x11 > > +/** > > + * DRM_CAP_CRTC_IN_VBLANK_EVENT > > + * > > + * If set to 1, the kernel supports reporting the CRTC ID in > > + * &drm_event_vblank.crtc_id. > > Does this not apply also to the pageflip / atomic completion event? Both DRM_EVENT_VBLANK and DRM_EVENT_FLIP_COMPLETE use the struct drm_event_vblank, so yes. I'll mention these two events explicitly. > > + */ > > #define DRM_CAP_CRTC_IN_VBLANK_EVENT 0x12 > > +/** > > + * DRM_CAP_SYNCOBJ > > + * > > + * If set to 1, the driver supports sync objects. See > > + * Documentation/gpu/drm-mm.rst, section "DRM Sync Objects". > > + */ > > #define DRM_CAP_SYNCOBJ 0x13 > > +/** > > + * DRM_CAP_SYNCOBJ_TIMELINE > > + * > > + * If set to 1, the driver supports timeline operations on sync objects. See > > + * Documentation/gpu/drm-mm.rst, section "DRM Sync Objects". > > + */ > > #define DRM_CAP_SYNCOBJ_TIMELINE 0x14 > > > > /* DRM_IOCTL_GET_CAP ioctl argument type */ > > I'm so happy seeing this doc appear! :-) > Sorry for trolling you into it. ;-) Np :) _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
