On Mon, Jul 30, 2012 at 12:16 PM, Alex Deucher <alexdeucher@xxxxxxxxx> wrote: > On Mon, Jul 30, 2012 at 12:03 PM, Alex Deucher <alexdeucher@xxxxxxxxx> wrote: >> On Mon, Jul 30, 2012 at 11:48 AM, Marek Olšák <maraeo@xxxxxxxxx> wrote: >>> On Mon, Jul 30, 2012 at 4:56 PM, Jerome Glisse <j.glisse@xxxxxxxxx> wrote: >>>> On Sun, Jul 29, 2012 at 1:04 PM, Marek Olšák <maraeo@xxxxxxxxx> wrote: >>>>> If we don't need stencil, don't allocate it. >>>>> If we need only stencil (like PIPE_FORMAT_S8_UINT), don't allocate depth. >>>>> >>>>> v2: actually do it correctly >>>> >>>> Big NAK >>>> >>>> We need to allocate stencil and depth no matter what. Otherwise it >>>> will lockup. You can take a look by poisonning the surface and see >>>> that when stencil is disabled or depth is disabled the hw still write >>>> to it. >>> >>> :) >>> >>> If what you say is true, then we're in a big trouble. Regardless of >>> this patch, we're in it right now, because we cannot fully disable >>> depth or stencil if the user binds a NULL zbuffer. That's clearly the >>> kind of issue that cannot be fixed in the allocator code and should be >>> fixed in r600g where the hardware is programmed. >>> >>> I *think* that the correct way to disable Z or stencil is to set the >>> Z_INVALID or STENCIL_INVALID format, respectively, and not by >>> disabling reads and writes. (cc'ing Alex to confirm that if he can). I >>> don't think the hardware designers have added those "invalid" formats >>> just for the lulz. Please see my latest kernel patch "drm/radeon/kms: >>> allow "invalid" DB formats as a means to disable DB" that tries to >>> address this issue. >> >> That is correct. I just verified with the hw team. If you allocate >> both buffers there are some restrictions in that they share tiling >> parameters, but you can set either buffer to _INVALID and allocate one >> or the other independently. > > Some further clarifications from the hw team. If you want to have > truly independent z and stencil buffers that allows for mixing and > matching, you need to make sure that any z and stencil buffer that can > be bound together must share the same addressing parameters (except > tile split), and you must disable the htile buffer on evergreen and > before (DB_Z_INFO.TILE_SURFACE_ENABLE=0) or disable the htile buffer > for stencil on cayman and newer > (DB_STENCIL_INFO.TILE_STENCIL_DISABLE=1). If you are only interested > in unbinding z or stencil independently (but not mixing and matching) > then you don't need to the above restrictions on the htile buffer. > You can do so by setting the format to INVALID. > > Alex Well somehow i can't reproduce might have been fixed by something like render backend fix. I should have write down how i saw this back in the day. Cheers, Jerome _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel
