On Wed, Jan 22, 2020 at 11:19 PM Sharat Masetty <smasetty@xxxxxxxxxxxxxx> wrote: > > This patch adds support for enabling Graphics Bus Interface(GBIF) > used in multiple A6xx series chipets. Also makes changes to the > PDC/RSC sequencing specifically required for A618. This is needed > for proper interfacing with RPMH. > > Signed-off-by: Sharat Masetty <smasetty@xxxxxxxxxxxxxx> > --- > diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c > index dc8ec2c..2ac9a51 100644 > --- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c > +++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c > @@ -378,6 +378,18 @@ static int a6xx_hw_init(struct msm_gpu *gpu) > struct a6xx_gpu *a6xx_gpu = to_a6xx_gpu(adreno_gpu); > int ret; > > + /* > + * During a previous slumber, GBIF halt is asserted to ensure > + * no further transaction can go through GPU before GPU > + * headswitch is turned off. > + * > + * This halt is deasserted once headswitch goes off but > + * incase headswitch doesn't goes off clear GBIF halt > + * here to ensure GPU wake-up doesn't fail because of > + * halted GPU transactions. > + */ > + gpu_write(gpu, REG_A6XX_GBIF_HALT, 0x0); > + > /* Make sure the GMU keeps the GPU on while we set it up */ > a6xx_gmu_set_oob(&a6xx_gpu->gmu, GMU_OOB_GPU_SET); > So I already brought this up on #freedreno but figured I'd follow up on the list. With linus/master, I'm seeing hard crashes (into usb crash mode) with the db845c, which I isolated down to this patch, and then to the chunk above. Dropping the gpu_write line above gets things booting again for me. Let me know if there are any follow on patches I can help validate. thanks -john
