drm/msm/a6xx: Skip crashdumper state if GPU needs_hw_init

I am seeing some crash logs which imply that we are trying to use
crashdumper hw to read back GPU state when the GPU isn't initialized.
This doesn't go well (for example, GPU could be in 32b address mode
and ignoring the upper bits of buffer that it is trying to dump state
to).

I'm not *quite* sure how we get into this state in the first place,
but lets not make a bad situation worse by triggering iova fault
crashes.

While we're at it, also add the information about whether the GPU is
initialized to the devcore dump to make this easier to see in the
logs (which makes the WARN_ON() redundant and even harmful because
it fills up the small bit of dmesg we get with the crash report).

Signed-off-by: Rob Clark <robdclark@chromium.org>
Link: https://lore.kernel.org/r/20211209193118.1163248-1-robdclark@gmail.com
Signed-off-by: Rob Clark <robdclark@chromium.org>

diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c
index bdd0059a81ff116d99e5995a1d72e479300e3c5c..55f443328d8e72e10b04921841de6703c1e970b3 100644 (file)
--- a/drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c
+++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu_state.c
@@ -49,6 +49,8 @@ struct a6xx_gpu_state {
        s32 hfi_queue_history[2][HFI_HISTORY_SZ];
 
        struct list_head objs;
+
+       bool gpu_initialized;
 };
 
 static inline int CRASHDUMP_WRITE(u64 *in, u32 reg, u32 val)
@@ -1001,7 +1003,8 @@ struct msm_gpu_state *a6xx_gpu_state_get(struct msm_gpu *gpu)
         * write out GPU state, so we need to skip this when the SMMU is
         * stalled in response to an iova fault
         */
-       if (!stalled && !a6xx_crashdumper_init(gpu, &_dumper)) {
+       if (!stalled && !gpu->needs_hw_init &&
+           !a6xx_crashdumper_init(gpu, &_dumper)) {
                dumper = &_dumper;
        }
 
@@ -1018,6 +1021,8 @@ struct msm_gpu_state *a6xx_gpu_state_get(struct msm_gpu *gpu)
        if (snapshot_debugbus)
                a6xx_get_debugbus(gpu, a6xx_state);
 
+       a6xx_state->gpu_initialized = !gpu->needs_hw_init;
+
        return  &a6xx_state->base;
 }
 
@@ -1246,6 +1251,8 @@ void a6xx_show(struct msm_gpu *gpu, struct msm_gpu_state *state,
        if (IS_ERR_OR_NULL(state))
                return;
 
+       drm_printf(p, "gpu-initialized: %d\n", a6xx_state->gpu_initialized);
+
        adreno_show(gpu, state, p);
 
        drm_puts(p, "gmu-log:\n");

diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.c b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
index 47cb40bdbd4394f4d8f31b2a5c2e7e9ce839f8ad..f33cfa4ef1c87866df83e4ad77e8174c34b2fde4 100644 (file)
--- a/drivers/gpu/drm/msm/adreno/adreno_gpu.c
+++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
@@ -504,7 +504,6 @@ int adreno_gpu_state_get(struct msm_gpu *gpu, struct msm_gpu_state *state)
        struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
        int i, count = 0;
 
-       WARN_ON(gpu->needs_hw_init);
        WARN_ON(!mutex_is_locked(&gpu->lock));
 
        kref_init(&state->ref);