Ben Widawsky <ben at bwidawsk.net> writes: > The interface's immediate purpose is to do synchronous timestamp queries > as required by GL_TIMESTAMP. The GPU has a register for reading the > timestamp but because that would normally require root access through > libpciaccess, the IOCTL can provide this service instead. > > Currently the implementation whitelists only the render ring timestamp > register, because that is the only thing we need to expose at this time. > > v2: make size implicit based on the register offset > Add a generation check > diff --git a/include/drm/i915_drm.h b/include/drm/i915_drm.h > index 8cc7083..fbe7757 100644 > --- a/include/drm/i915_drm.h > +++ b/include/drm/i915_drm.h > @@ -203,6 +203,7 @@ typedef struct _drm_i915_sarea { > #define DRM_I915_GEM_WAIT 0x2c > #define DRM_I915_GEM_CONTEXT_CREATE 0x2d > #define DRM_I915_GEM_CONTEXT_DESTROY 0x2e > +#define DRM_I915_REG_READ 0x30 Is 0x2f some other outstanding ioctl? Other than that, Reviewed-by: Eric Anholt <eric at anholt.net> Note: we have requests both by Arjan and by Valve for the functionality that this patch will allow. -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 197 bytes Desc: not available URL: <http://lists.freedesktop.org/archives/intel-gfx/attachments/20120718/54465894/attachment.pgp>