A8XX GPUs have two sets of protect registers: 64 global slots and 16
pipe specific slots. The last-span-unbound feature is only available
on pipe protect registers, and should always target pipe slot 15.

This matches the downstream driver which hardcodes pipe slot 15 for
all A8XX GPUs (GRAPHICS.LA.15.0.r1) and resolves protect errors on
A810.

Signed-off-by: Alexander Koskovich <akoskovich@pm.me>
---
 drivers/gpu/drm/msm/adreno/a8xx_gpu.c | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/msm/adreno/a8xx_gpu.c b/drivers/gpu/drm/msm/adreno/a8xx_gpu.c
index 5af82d43f1e4..63387ee9b04a 100644
--- a/drivers/gpu/drm/msm/adreno/a8xx_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/a8xx_gpu.c
@@ -252,11 +252,12 @@ static void a8xx_set_cp_protect(struct msm_gpu *gpu)
 	}
 
 	/*
-	 * Last span feature is only supported on PIPE specific register.
-	 * So update those here
+	 * Last span setting is only being applied to the last pipe specific
+	 * register. Hence duplicate the last span from protect reg into the
+	 * BR and BV protect reg pipe 15.
 	 */
-	a8xx_write_pipe(gpu, PIPE_BR, REG_A8XX_CP_PROTECT_PIPE(protect->count_max), final_cfg);
-	a8xx_write_pipe(gpu, PIPE_BV, REG_A8XX_CP_PROTECT_PIPE(protect->count_max), final_cfg);
+	a8xx_write_pipe(gpu, PIPE_BR, REG_A8XX_CP_PROTECT_PIPE(15), final_cfg);
+	a8xx_write_pipe(gpu, PIPE_BV, REG_A8XX_CP_PROTECT_PIPE(15), final_cfg);
 
 	a8xx_aperture_clear(gpu);
 }

-- 
2.53.0