drm/amdgpu: Wait for GFX idle before PTL state transition

Ensure GFX engine is idle before switching PTL state to prevent
register access violations and CP hang. This addresses the race
condition where in-flight GPU commands could conflict with PTL
state changes.

Signed-off-by: Perry Yuan <perry.yuan@amd.com>
Reviewed-by: Yifan Zhang <yifan1.zhang@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
index 5bea583732cbb98ccd1de48c3352efff38cf813e..a719399bcdd5d2ff24545898975717fb54e15aa5 100644 (file)
--- a/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_chardev.c
@@ -1792,6 +1792,11 @@ static int kfd_ptl_control(struct kfd_process_device *pdd, bool enable)
        if (adev->kfd.init_complete)
                amdgpu_amdkfd_stop_sched(adev, pdd->dev->node_id);
 
+       /* Wait for GFX to be idle before PTL operation */
+       ret = amdgpu_device_ip_wait_for_idle(adev, AMD_IP_BLOCK_TYPE_GFX);
+       if (ret)
+               return -ETIMEDOUT;
+
        ret = pdd->dev->kfd2kgd->ptl_ctrl(adev, PSP_PTL_PERF_MON_SET,
                                          &ptl_state,
                                          &pref_format1,