Hi Eric,
On 1 December 2015 at 20:35, Eric Anholt eric@anholt.net wrote:
Since we have no MMU, the kernel needs to validate that the submitted shader code won't make any accesses to memory that the user doesn't control, which involves banning some operations (general purpose DMA writes), and tracking where we need to write out pointers for other operations (texture sampling). Once it's validated, we return a GEM BO containing the shader, which doesn't allow mapping for write or exporting to other subsystems.
Signed-off-by: Eric Anholt eric@anholt.net
drivers/gpu/drm/vc4/Makefile | 3 +- drivers/gpu/drm/vc4/vc4_bo.c | 140 ++++++++ drivers/gpu/drm/vc4/vc4_drv.c | 9 +- drivers/gpu/drm/vc4/vc4_drv.h | 50 +++ drivers/gpu/drm/vc4/vc4_qpu_defines.h | 264 +++++++++++++++
May I suggest that one 'exports' the header to something like libdrm_vc4 ? There are patches in flight for nouveau which in similar fashion, allow userspare to reuse existing api/abi.
-Emil