Hi Rob, On Tue, Jan 30, 2018 at 9:36 PM, Robert Foss <robert.f...@collabora.com> wrote: >>>>>> uint32_t (*get_fd)(buffer_handle_t handle, uint32_t plane); >>>>>> uint64_t (*get_modifier)(buffer_handle_t handle, uint32_t >>>>>> plane); >>>>>> uint32_t (*get_offsets)(buffer_handle_t handle, uint32_t plane); >>>>>> uint32_t (*get_stride)(buffer_handle_t handle, uint32_t plane); >>>>>> ... >>>>>> } gralloc_funcs_t; >> >> >> These ones? > >> Yeah, if we could retrieve such function pointer struct using perform >> or any equivalent (like the implementation-specific methods in >> gralloc1, but not sure if that's going to be used in practice >> anywhere), it could work for us. > > > So this is where you and Rob Herring lose me, I don't think I understand > quite how the gralloc1 call would be used, and how it would tie into this > handle struct. I think I could do with some guidance on this.
This would be very similar to gralloc0 perform call. gralloc1 implementations need to provide getFunction() callback [1], which returns a pointer to given function. The list of standard functions is defined in the gralloc1.h header [2], but we could take some random big number and use it for our function that fills in provided gralloc_funcs_t struct with necessary pointers. [1] https://android.googlesource.com/platform/hardware/libhardware/+/master/include/hardware/gralloc1.h#300 [2] https://android.googlesource.com/platform/hardware/libhardware/+/master/include/hardware/gralloc1.h#134 With this, the buffer consumers (e.g. Mesa) would look like this: consume_buffer(priv, handle) { gralloc_funcs_t funcs; if (priv->gralloc1) { DRM_GRALLOC1_PFN_GET_GRALLOC_FUNCS get_gralloc_funcs; get_gralloc_func = priv->gralloc1->getFunction(priv->gralloc1, DRM_GRALLOC1_FUNCTION_GET_GRALLOC_FUNCS); get_gralloc_func(priv->gralloc1, handle, &funcs); // Not sure if the handle is even necessary } else /* gralloc0 */ { priv->gralloc0->perform(priv->gralloc0, DRM_GRALLOC_PERFORM_GET_GRALLOC_FUNCS, &funcs); } // funcs has everything that the consumer needs to deal with the buffer } Best regards, Tomasz _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev
