On Fri, May 18, 2018 at 11:58:19PM +0200, Thierry Reding wrote: > On Sat, May 19, 2018 at 12:42:22AM +0300, Dmitry Osipenko wrote: > > On 18.05.2018 23:33, Thierry Reding wrote: > > > From: Thierry Reding > > > > > > Document the userspace ABI with kerneldoc to provide some information on > > > how to use it. > > > > > > v2: > > > - keep GEM object creation flags for ABI compatibility > > > - fix typo in struct drm_tegra_syncpt_incr kerneldoc > > > - fix typos in struct drm_tegra_submit kerneldoc > > > - reworded some descriptions as suggested > > > > > > Signed-off-by: Thierry Reding > > > --- > > > include/uapi/drm/tegra_drm.h | 480 ++++++++++++++++++++++++++++++++++- > > > 1 file changed, 471 insertions(+), 9 deletions(-) > > > > > > diff --git a/include/uapi/drm/tegra_drm.h b/include/uapi/drm/tegra_drm.h > > > index 99e15d82d1e9..7e121c69cd9a 100644 > > > --- a/include/uapi/drm/tegra_drm.h > > > +++ b/include/uapi/drm/tegra_drm.h > > > @@ -32,143 +32,605 @@ extern "C" { > > > #define DRM_TEGRA_GEM_CREATE_TILED (1 << 0) > > > #define DRM_TEGRA_GEM_CREATE_BOTTOM_UP (1 << 1) > > > > > > +/** > > > + * struct drm_tegra_gem_create - parameters for the GEM object creation IOCTL > > > + */ > > > struct drm_tegra_gem_create { > > > + /** > > > + * @size: > > > + * > > > + * The size, in bytes, of the buffer object to be created. > > > + */ > > > __u64 size; > > > + > > > + /** > > > + * @flags: > > > + * > > > + * A bitmask of flags that influence the creation of GEM objects: > > > + * > > > + * DRM_TEGRA_GEM_CREATE_TILED > > > + * Use the 16x16 tiling format for this buffer. > > > + * > > > + * DRM_TEGRA_GEM_CREATE_BOTTOM_UP > > > + * The buffer has a bottom-up layout. > > > + */ > > > __u32 flags; > > > + > > > + /** > > > + * @handle: > > > + * > > > + * The handle of the created GEM object. Set by the kernel upon > > > + * successful completion of the IOCTL. > > > + */ > > > __u32 handle; > > > }; > > > > > > +/** > > > + * struct drm_tegra_gem_mmap - parameters for the GEM mmap IOCTL > > > + */ > > > struct drm_tegra_gem_mmap { > > > + /** > > > + * @handle: > > > + * > > > + * Handle of the GEM object to obtain an mmap offset for. > > > + */ > > > __u32 handle; > > > + > > > + /** > > > + * @pad: > > > + * > > > + * Structure padding that may be used in the future. Must be 0. > > > + */ > > > __u32 pad; > > > + > > > + /** > > > + * @offset: > > > + * > > > + * The mmap offset for the given GEM object. Set by the kernel upon > > > + * successful completion of the IOCTL. > > > + */ > > > __u64 offset; > > > }; > > > > > > +/** > > > + * struct drm_tegra_syncpt_read - parameters for the read syncpoint IOCTL > > > + */ > > > struct drm_tegra_syncpt_read { > > > + /** > > > + * @id: > > > + * > > > + * ID of the syncpoint to read the current value from. > > > + */ > > > __u32 id; > > > + > > > + /** > > > + * @value: > > > + * > > > + * The current syncpoint value. Set by the kernel upon successful > > > + * completion of the IOCTL. > > > + */ > > > __u32 value; > > > }; > > > > > > +/** > > > + * struct drm_tegra_syncpt_incr - parameters for the increment syncpoint IOCTL > > > + */ > > > struct drm_tegra_syncpt_incr { > > > + /** > > > + * @id: > > > + * > > > + * ID of the syncpoint to increment. > > > + */ > > > __u32 id; > > > + > > > + /** > > > + * @pad: > > > + * > > > + * Structure padding that may be used in the future. Must be 0. > > > + */ > > > __u32 pad; > > > }; > > > > > > +/** > > > + * struct drm_tegra_syncpt_wait - parameters for the wait syncpoint IOCTL > > > + */ > > > struct drm_tegra_syncpt_wait { > > > + /** > > > + * @id: > > > + * > > > + * ID of the syncpoint to wait on. > > > + */ > > > __u32 id; > > > + > > > + /** > > > + * @thresh: > > > + * > > > + * Threshold value for which to wait. > > > + */ > > > __u32 thresh; > > > + > > > + /** > > > + * @timeout: > > > + * > > > + * Timeout, in milliseconds, to wait. > > > + */ > > > __u32 timeout; > > > + > > > + /** > > > + * @value: > > > + * > > > + * The new syncpoint value after the wait. Set by the kernel upon > > > + * successful completion of the IOCTL. > > > + */ > > > __u32 value; > > > }; > > > > > > #define DRM_TEGRA_NO_TIMEOUT (0xffffffff) > > > > > > +/** > > > + * struct drm_tegra_open_channel - parameters for the open channel IOCTL > > > + */ > > > struct drm_tegra_open_channel { > > > + /** > > > + * @client: > > > + * > > > + * The client ID for this channel. > > > + */ > > > __u32 client; > > > + > > > + /** > > > + * @pad: > > > + * > > > + * Structure padding that may be used in the future. Must be 0. > > > + */ > > > __u32 pad; > > > + > > > + /** > > > + * @context: > > > + * > > > + * The application context of this channel. Set by the kernel upon > > > + * successful completion of the IOCTL. This context needs to be passed > > > + * to the DRM_TEGRA_CHANNEL_CLOSE or the DRM_TEGRA_SUBMIT IOCTLs. > > > + */ > > > __u64 context; > > > }; > > > > > > +/** > > > + * struct drm_tegra_close_channel - parameters for the close channel IOCTL > > > + */ > > > struct drm_tegra_close_channel { > > > + /** > > > + * @context: > > > + * > > > + * The application context of this channel. This is obtained from the > > > + * DRM_TEGRA_OPEN_CHANNEL IOCTL. > > > + */ > > > __u64 context; > > > }; > > > > > > +/** > > > + * struct drm_tegra_get_syncpt - parameters for the get syncpoint IOCTL > > > + */ > > > struct drm_tegra_get_syncpt { > > > + /** > > > + * @context: > > > + * > > > + * The application context identifying the channel for which to obtain > > > + * the syncpoint ID. > > > + */ > > > __u64 context; > > > + > > > + /** > > > + * @index: > > > + * > > > + * Index of the client syncpoint for which to obtain the ID. > > > + */ > > > __u32 index; > > > + > > > + /** > > > + * @id: > > > + * > > > + * The ID of the given syncpoint. Set by the kernel upon successful > > > + * completion of the IOCTL. > > > + */ > > > __u32 id; > > > }; > > > > > > +/** > > > + * struct drm_tegra_get_syncpt_base - parameters for the get wait base IOCTL > > > + */ > > > struct drm_tegra_get_syncpt_base { > > > + /** > > > + * @context: > > > + * > > > + * The application context identifying for which channel to obtain the > > > + * wait base. > > > + */ > > > __u64 context; > > > + > > > + /** > > > + * @syncpt: > > > + * > > > + * ID of the syncpoint for which to obtain the wait base. > > > + */ > > > __u32 syncpt; > > > + > > > + /** > > > + * @id: > > > + * > > > + * The ID of the wait base corresponding to the client syncpoint. Set > > > + * by the kernel upon successful completion of the IOCTL. > > > + */ > > > __u32 id; > > > }; > > > > > > +/** > > > + * struct drm_tegra_syncpt - syncpoint increment operation > > > + */ > > > struct drm_tegra_syncpt { > > > + /** > > > + * @id: > > > + * > > > + * ID of the syncpoint to operate on. > > > + */ > > > __u32 id; > > > + > > > + /** > > > + * @incrs: > > > + * > > > + * Number of increments to perform for the syncpoint. > > > + */ > > > __u32 incrs; > > > }; > > > > > > +/** > > > + * struct drm_tegra_cmdbuf - structure describing a command buffer > > > + */ > > > struct drm_tegra_cmdbuf { > > > + /** > > > + * @handle: > > > + * > > > + * Handle to a GEM object containing the command buffer. > > > + */ > > > __u32 handle; > > > + > > > + /** > > > + * @offset: > > > + * > > > + * Offset, in bytes, into the GEM object identified by @handle at > > > + * which the command buffer starts. > > > + */ > > > __u32 offset; > > > + > > > + /** > > > + * @words: > > > + * > > > + * Number of 32-bit words in this command buffer. > > > + */ > > > __u32 words; > > > + > > > + /** > > > + * @pad: > > > + * > > > + * Structure padding that may be used in the future. Must be 0. > > > + */ > > > __u32 pad; > > > }; > > > > > > +/** > > > + * struct drm_tegra_reloc - GEM object relocation structure > > > + */ > > > struct drm_tegra_reloc { > > > struct { > > > + /** > > > + * @cmdbuf.handle: > > > + * > > > + * Handle to the GEM object containing the command buffer for > > > + * which to perform this GEM object relocation. > > > + */ > > > __u32 handle; > > > + > > > + /** > > > + * @cmdbuf.offset: > > > + * > > > + * Offset, in bytes, into the command buffer at which to > > > + * insert the relocated address. > > > + */ > > > __u32 offset; > > > } cmdbuf; > > > struct { > > > + /** > > > + * @target.handle: > > > + * > > > + * Handle to the GEM object to be relocated. > > > + */ > > > __u32 handle; > > > + > > > + /** > > > + * @target.offset: > > > + * > > > + * Offset, in bytes, into the target GEM object at which the > > > + * relocated data starts. > > > + */ > > > __u32 offset; > > > } target; > > > + > > > + /** > > > + * @shift: > > > + * > > > + * The number of bits by which to shift relocated addresses. > > > + */ > > > __u32 shift; > > > + > > > + /** > > > + * @pad: > > > + * > > > + * Structure padding that may be used in the future. Must be 0. > > > + */ > > > __u32 pad; > > > }; > > > > > > +/** > > > + * struct drm_tegra_waitchk - wait check structure > > > + */ > > > struct drm_tegra_waitchk { > > > + /** > > > + * @handle: > > > + * > > > + * Handle to the GEM object containing a command stream on which to > > > + * perform the wait check. > > > + */ > > > __u32 handle; > > > + > > > + /** > > > + * @offset: > > > + * > > > + * Offset, in bytes, of the location in the command stream to perform > > > + * the wait check on. > > > + */ > > > __u32 offset; > > > + > > > + /** > > > + * @syncpt: > > > + * > > > + * ID of the syncpoint to wait check. > > > + */ > > > __u32 syncpt; > > > + > > > + /** > > > + * @thresh: > > > + * > > > + * Threshold value for which to check. > > > + */ > > > __u32 thresh; > > > }; > > > > > > +/** > > > + * struct drm_tegra_submit - job submission structure > > > + */ > > > struct drm_tegra_submit { > > > + /** > > > + * @context: > > > + * > > > + * The application context identifying the channel to use for the > > > + * execution of this job. > > > + */ > > > __u64 context; > > > + > > > + /** > > > + * @num_syncpts: > > > + * > > > + * The number of syncpoints operated on by this job. > > > + */ > > > __u32 num_syncpts; > > > + > > > + /** > > > + * @num_cmdbufs: > > > + * > > > + * The number of command buffers to execute as part of this job. > > > + */ > > > __u32 num_cmdbufs; > > > + > > > + /** > > > + * @num_relocs: > > > + * > > > + * The number of relocations to perform before executing this job. > > > + */ > > > __u32 num_relocs; > > > + > > > + /** > > > + * @num_waitchks: > > > + * > > > + * The number of wait checks to perform as part of this job. > > > + */ > > > __u32 num_waitchks; > > > + > > > + /** > > > + * @waitchk_mask: > > > + * > > > + * Bitmask of valid wait checks. > > > + */ > > > __u32 waitchk_mask; > > > + > > > + /** > > > + * @timeout: > > > + * > > > + * Timeout, in milliseconds, before this job is cancelled. > > > + */ > > > __u32 timeout; > > > + > > > + /** > > > + * @syncpts: > > > + * > > > + * A pointer to @num_syncpts &struct drm_tegra_syncpt structures that > > > > I'm not sure whether this "pointer to @num_syncpts" makes sense, shouldn't it be: > > > > A pointer to &struct drm_tegra_syncpt structures that... > > > > ? > > > > Same for the @cmdbufs/@relocs/@waitchks members. > > I wanted to have the references to those fields in the text so that it > becomes obvious that num_syncpts defines the number of entries in this > syncpts array. > > Perhaps a better formulation would be: > > A pointer to an array of @num_syncpts &struct drm_tegra_syncpt > structure that... > > ? Another alternative may be: /** * @syncpts: * * A pointer to an array of &struct drm_tegra_syncpt structure that * specify the syncpoint operations performed as part of this job. * The number of elements in the array must be equal to the value * given by @num_syncpts. */ That's slightly easier to read but also very explicit in relating both fields to one another. Perhaps a two-way link can be established by adding something like this to the description of @num_syncpts: /** * @num_syncpts: * * The number of syncpoints operated on by this job. This defines * the length of the array pointed to by @syncpts. */ Thierry