drm/amdkfd: Add wavefront context save state retrieval ioctl

Wavefront context save data is of interest to userspace clients for
debugging static wavefront state. The MQD contains two parameters
required to parse the control stack and the control stack itself
is kept in the MQD from gfx9 onwards.

Add an ioctl to fetch the context save area and control stack offsets
and to copy the control stack to a userspace address if it is kept in
the MQD.

Signed-off-by: Jay Cornwall <Jay.Cornwall@amd.com>
Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>
Signed-off-by: Felix Kuehling <Felix.Kuehling@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 37 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c b/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
index ec0d62a16e53..408888911361 100644
--- a/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
+++ b/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
@@ -1528,6 +1528,41 @@ static int process_termination_nocpsch(struct device_queue_manager *dqm,
 	return retval;
 }
 
+static int get_wave_state(struct device_queue_manager *dqm,
+			  struct queue *q,
+			  void __user *ctl_stack,
+			  u32 *ctl_stack_used_size,
+			  u32 *save_area_used_size)
+{
+	struct mqd_manager *mqd;
+	int r;
+
+	dqm_lock(dqm);
+
+	if (q->properties.type != KFD_QUEUE_TYPE_COMPUTE ||
+	    q->properties.is_active || !q->device->cwsr_enabled) {
+		r = -EINVAL;
+		goto dqm_unlock;
+	}
+
+	mqd = dqm->ops.get_mqd_manager(dqm, KFD_MQD_TYPE_COMPUTE);
+	if (!mqd) {
+		r = -ENOMEM;
+		goto dqm_unlock;
+	}
+
+	if (!mqd->get_wave_state) {
+		r = -EINVAL;
+		goto dqm_unlock;
+	}
+
+	r = mqd->get_wave_state(mqd, q->mqd, ctl_stack, ctl_stack_used_size,
+				save_area_used_size);
+
+dqm_unlock:
+	dqm_unlock(dqm);
+	return r;
+}
 
 static int process_termination_cpsch(struct device_queue_manager *dqm,
 		struct qcm_process_device *qpd)
@@ -1649,6 +1684,7 @@ struct device_queue_manager *device_queue_manager_init(struct kfd_dev *dev)
 		dqm->ops.process_termination = process_termination_cpsch;
 		dqm->ops.evict_process_queues = evict_process_queues_cpsch;
 		dqm->ops.restore_process_queues = restore_process_queues_cpsch;
+		dqm->ops.get_wave_state = get_wave_state;
 		break;
 	case KFD_SCHED_POLICY_NO_HWS:
 		/* initialize dqm for no cp scheduling */
@@ -1668,6 +1704,7 @@ struct device_queue_manager *device_queue_manager_init(struct kfd_dev *dev)
 		dqm->ops.evict_process_queues = evict_process_queues_nocpsch;
 		dqm->ops.restore_process_queues =
 			restore_process_queues_nocpsch;
+		dqm->ops.get_wave_state = get_wave_state;
 		break;
 	default:
 		pr_err("Invalid scheduling policy %d\n", dqm->sched_policy);