6.15-stable review patch. If anyone has any objections, please let me know.
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From: Connor Abbott cwabbott0@gmail.com
[ Upstream commit 2b520c6104f34e3a548525173c38ebca4402cac3 ]
Calling this packet is necessary when we switch contexts because there are various pieces of state used by userspace to synchronize between BR and BV that are persistent across submits and we need to make sure that they are in a "safe" state when switching contexts. Otherwise a userspace submission in one context could cause another context to function incorrectly and hang, effectively a denial of service (although without leaking data). This was missed during initial a7xx bringup.
Fixes: af66706accdf ("drm/msm/a6xx: Add skeleton A7xx support") Signed-off-by: Connor Abbott cwabbott0@gmail.com Patchwork: https://patchwork.freedesktop.org/patch/654924/ Signed-off-by: Rob Clark robin.clark@oss.qualcomm.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/msm/adreno/a6xx_gpu.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+)
diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c index 90991ba5a4ae1..742132feb19cc 100644 --- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c +++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c @@ -130,6 +130,20 @@ static void a6xx_set_pagetable(struct a6xx_gpu *a6xx_gpu, OUT_RING(ring, lower_32_bits(rbmemptr(ring, fence))); OUT_RING(ring, upper_32_bits(rbmemptr(ring, fence))); OUT_RING(ring, submit->seqno - 1); + + OUT_PKT7(ring, CP_THREAD_CONTROL, 1); + OUT_RING(ring, CP_SET_THREAD_BOTH); + + /* Reset state used to synchronize BR and BV */ + OUT_PKT7(ring, CP_RESET_CONTEXT_STATE, 1); + OUT_RING(ring, + CP_RESET_CONTEXT_STATE_0_CLEAR_ON_CHIP_TS | + CP_RESET_CONTEXT_STATE_0_CLEAR_RESOURCE_TABLE | + CP_RESET_CONTEXT_STATE_0_CLEAR_BV_BR_COUNTER | + CP_RESET_CONTEXT_STATE_0_RESET_GLOBAL_LOCAL_TS); + + OUT_PKT7(ring, CP_THREAD_CONTROL, 1); + OUT_RING(ring, CP_SET_THREAD_BR); }
if (!sysprof) {