Hi, This is a request for comments on the idea of being able to map gbm bos and how to implement it. The idea here is to take advantage of UMA atchitectures when the contents on the screen are a mix of GPU and CPU rendered.
One of the problems of adding a map entry point to gbm is the fact that it relies on the DRI image extension to do all the work. Instead of extending that extension, the proposal here is to support different gbm backends, which may optionally support mapping. However, this requires changes to the EGL implementation, since the current implementation is heavily coupled with gbm's dri backend. The one problem in doing that is that the dri driver and gbm device no longer share the same fd, so another way of sharing buffers between then is necessary. As a stop gap measure I added the ability for gbm to provide gem names (given that dri 2's interface relies on names anyway), but a better solution is needed. This would also let the dependency between libgbm and libEGL to be moved to gbm's dri backend, and open up the possibility of running a Wayland compositor on KMS with a software renderer that would still be able to use overlays. This ties with the fast start patches I submitted to the wayland mailing list. Still talking about Wayland, I have a rough plan on how to make this usable with that too. Since gbm is already Wayland aware to some extent, given that it is able to import wl_buffers into gbm_bos, it seems like a natural extension that it would be able to do the converse. That ability together with an entry point for creating a gbm_device for a given wl_display would be enough for making this available for any wayland client. Any comments on this will be highly appreciated. Thanks, Ander Ander Conselvan de Oliveira (3): gbm: Add intel backend egl/dri: Add gbm platform gbm: Add entry points for mapping and unmapping bos configure.ac | 5 +- src/egl/drivers/dri2/Makefile.am | 5 + src/egl/drivers/dri2/egl_dri2.c | 6 + src/egl/drivers/dri2/egl_dri2.h | 11 +- src/egl/drivers/dri2/platform_gbm.c | 545 +++++++++++++++++++++++++++++++++++ src/egl/main/Makefile.am | 5 + src/egl/main/egldisplay.c | 3 +- src/egl/main/egldisplay.h | 1 + src/gbm/Makefile.am | 12 + src/gbm/backends/dri/gbm_dri.c | 11 + src/gbm/backends/intel/gbm_intel.c | 269 +++++++++++++++++ src/gbm/backends/intel/gbm_intel.h | 77 +++++ src/gbm/main/backend.c | 2 + src/gbm/main/common_drm.h | 1 + src/gbm/main/gbm.c | 54 +++- src/gbm/main/gbm.h | 18 ++ src/gbm/main/gbmint.h | 5 + 17 files changed, 1022 insertions(+), 8 deletions(-) create mode 100644 src/egl/drivers/dri2/platform_gbm.c create mode 100644 src/gbm/backends/intel/gbm_intel.c create mode 100644 src/gbm/backends/intel/gbm_intel.h -- 1.7.9.5 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
