drm/etnaviv: consider completed fence seqno in hang check

[ Upstream commit cdd156955f946beaa5f3a00d8ccf90e5a197becc ]

Some GPU heavy test programs manage to trigger the hangcheck quite often.
If there are no other GPU users in the system and the test program
exhibits a very regular structure in the commandstreams that are being
submitted, we can end up with two distinct submits managing to trigger
the hangcheck with the FE in a very similar address range. This leads
the hangcheck to believe that the GPU is stuck, while in reality the GPU
is already busy working on a different job. To avoid those spurious
GPU resets, also remember and consider the last completed fence seqno
in the hang check.

Reported-by: Joerg Albert <joerg.albert@iav.de>
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_gpu.h b/drivers/gpu/drm/etnaviv/etnaviv_gpu.h
index 1c75c8ed5bcea2c5bec1d923ed35fc9a78884c67..85eddd492774d59c34189f6768e24e3f42dd8766 100644 (file)
--- a/drivers/gpu/drm/etnaviv/etnaviv_gpu.h
+++ b/drivers/gpu/drm/etnaviv/etnaviv_gpu.h
@@ -130,6 +130,7 @@ struct etnaviv_gpu {
 
        /* hang detection */
        u32 hangcheck_dma_addr;
+       u32 hangcheck_fence;
 
        void __iomem *mmio;
        int irq;

diff --git a/drivers/gpu/drm/etnaviv/etnaviv_sched.c b/drivers/gpu/drm/etnaviv/etnaviv_sched.c
index feb6da1b6cebc6b5646c58e2f551969f257b5edc..bbf391f48f94966eeff1a4ca459955c9943fc843 100644 (file)
--- a/drivers/gpu/drm/etnaviv/etnaviv_sched.c
+++ b/drivers/gpu/drm/etnaviv/etnaviv_sched.c
@@ -107,8 +107,10 @@ static enum drm_gpu_sched_stat etnaviv_sched_timedout_job(struct drm_sched_job
         */
        dma_addr = gpu_read(gpu, VIVS_FE_DMA_ADDRESS);
        change = dma_addr - gpu->hangcheck_dma_addr;
-       if (change < 0 || change > 16) {
+       if (gpu->completed_fence != gpu->hangcheck_fence ||
+           change < 0 || change > 16) {
                gpu->hangcheck_dma_addr = dma_addr;
+               gpu->hangcheck_fence = gpu->completed_fence;
                goto out_no_timeout;
        }