On Wed, Jan 28, 2015 at 05:57:56PM +0000, Tvrtko Ursulin wrote: > > On 01/28/2015 05:37 PM, Daniel Vetter wrote: > >From: Rob Clark <robdclark@xxxxxxxxx> > > > >In DRM/KMS we are lacking a good way to deal with tiled/compressed > >formats. Especially in the case of dmabuf/prime buffer sharing, where > >we cannot always rely on under-the-hood flags passed to driver specific > >gem-create ioctl to pass around these extra flags. > > > >The proposal is to add a per-plane format modifier. This allows to, if > >necessary, use different tiling patters for sub-sampled planes, etc. > >The format modifiers are added at the end of the ioctl struct, so for > >legacy userspace it will be zero padded. > > > >TODO how best to deal with assignment of modifier token values? The > >rough idea was to namespace things with an 8bit vendor-id, and then > >beyond that it is treated as an opaque value. But that was a relatively > >arbitrary choice. There are cases where same tiling pattern and/or > >compression is supported by various different vendors. So we should > >standardize to use the vendor-id and value of the first one who > >documents the format? > > Maybe: > __u64 modifier[4]; > __u64 vendor_modifier[4]; Seems rendundant since the modifier added in this patch is already vendor specific. Or what exactly are you trying to accomplish here? -Daniel > > ? > > Regards, > > Tvrtko -- Daniel Vetter Software Engineer, Intel Corporation +41 (0) 79 365 57 48 - http://blog.ffwll.ch _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
