46  * for GPU/CPU synchronization.  When the fence is written,
47  * it is expected that all buffers associated with that fence
92  * amdgpu_fence_write - write a fence value
94  * @ring: ring the fence is associated with
97  * Writes a fence value to memory (all asics).
108  * amdgpu_fence_read - read a fence value
110  * @ring: ring the fence is associated with
112  * Reads a fence value from memory (all asics).
113  * Returns the value of the fence read from memory.
129  * amdgpu_fence_emit - emit a fence on the requested ring
131  * @ring: ring the fence is associated with
132  * @f: resulting fence object
133  * @job: job the fence is embedded in
136  * Emits a fence command on the requested ring (all asics).
143 	struct dma_fence *fence;  in amdgpu_fence_emit()  local
150 		/* create a sperate hw fence */  in amdgpu_fence_emit()
154 		fence = &am_fence->base;  in amdgpu_fence_emit()
157 		/* take use of job-embedded fence */  in amdgpu_fence_emit()
158 		fence = &job->hw_fence;  in amdgpu_fence_emit()
164 		fence->seqno = seq;  in amdgpu_fence_emit()
165 		/* TO be inline with external fence creation and other drivers */  in amdgpu_fence_emit()
166 		dma_fence_get(fence);  in amdgpu_fence_emit()
169 			dma_fence_init(fence, &amdgpu_job_fence_ops,  in amdgpu_fence_emit()
173 			dma_fence_get(fence);  in amdgpu_fence_emit()
175 			dma_fence_init(fence, &amdgpu_fence_ops,  in amdgpu_fence_emit()
200 	to_amdgpu_fence(fence)->start_timestamp = ktime_get();  in amdgpu_fence_emit()
203 	 * emitting the fence would mess up the hardware ring buffer.  in amdgpu_fence_emit()
205 	rcu_assign_pointer(*ptr, dma_fence_get(fence));  in amdgpu_fence_emit()
207 	*f = fence;  in amdgpu_fence_emit()
213  * amdgpu_fence_emit_polling - emit a fence on the requeste ring
215  * @ring: ring the fence is associated with
219  * Emits a fence command on the requested ring (all asics).
220  * Used For polling fence.
261  * amdgpu_fence_process - check for fence activity
265  * Checks the current fence value and calculates the last
266  * signalled fence value. Wakes the fence queue if the
269  * Returns true if fence was processed
294 		struct dma_fence *fence, **ptr;  in amdgpu_fence_process()  local
300 		/* There is always exactly one thread signaling this fence slot */  in amdgpu_fence_process()
301 		fence = rcu_dereference_protected(*ptr, 1);  in amdgpu_fence_process()
304 		if (!fence)  in amdgpu_fence_process()
307 		dma_fence_signal(fence);  in amdgpu_fence_process()
308 		dma_fence_put(fence);  in amdgpu_fence_process()
321  * Checks for fence activity.
329 		DRM_WARN("Fence fallback timer expired on ring %s\n", ring->name);  in amdgpu_fence_fallback()
335  * @ring: ring index the fence is associated with
343 	struct dma_fence *fence, **ptr;  in amdgpu_fence_wait_empty()  local
351 	fence = rcu_dereference(*ptr);  in amdgpu_fence_wait_empty()
352 	if (!fence || !dma_fence_get_rcu(fence)) {  in amdgpu_fence_wait_empty()
358 	r = dma_fence_wait(fence, false);  in amdgpu_fence_wait_empty()
359 	dma_fence_put(fence);  in amdgpu_fence_wait_empty()
366  * @ring: ring index the fence is associated with
387  * @ring: ring the fence is associated with
398 	 * but it's ok to report slightly wrong fence count here.  in amdgpu_fence_count_emitted()
407  * amdgpu_fence_last_unsignaled_time_us - the time fence emitted until now
408  * @ring: ring the fence is associated with
410  * Find the earliest fence unsignaled until now, calculate the time delta
411  * between the time fence emitted and now.
416 	struct dma_fence *fence;  in amdgpu_fence_last_unsignaled_time_us()  local
426 	fence = drv->fences[last_seq];  in amdgpu_fence_last_unsignaled_time_us()
427 	if (!fence)  in amdgpu_fence_last_unsignaled_time_us()
431 		to_amdgpu_fence(fence)->start_timestamp);  in amdgpu_fence_last_unsignaled_time_us()
435  * amdgpu_fence_update_start_timestamp - update the timestamp of the fence
436  * @ring: ring the fence is associated with
437  * @seq: the fence seq number to update.
440  * The function called at the time the fence and related ib is about to
442  * with amdgpu_fence_process to modify the same fence.
447 	struct dma_fence *fence;  in amdgpu_fence_update_start_timestamp()  local
450 	fence = drv->fences[seq];  in amdgpu_fence_update_start_timestamp()
451 	if (!fence)  in amdgpu_fence_update_start_timestamp()
454 	to_amdgpu_fence(fence)->start_timestamp = timestamp;  in amdgpu_fence_update_start_timestamp()
458  * amdgpu_fence_driver_start_ring - make the fence driver
461  * @ring: ring to start the fence driver on
465  * Make the fence driver ready for processing (all asics).
467  * start the fence driver on the rings it has.
481 		/* put fence directly behind firmware */  in amdgpu_fence_driver_start_ring()
492 	DRM_DEV_DEBUG(adev->dev, "fence driver on ring %s use gpu addr 0x%016llx\n",  in amdgpu_fence_driver_start_ring()
498  * amdgpu_fence_driver_init_ring - init the fence driver
501  * @ring: ring to init the fence driver on
503  * Init the fence driver for the requested ring (all asics).
536  * amdgpu_fence_driver_sw_init - init the fence driver
541  * Init the fence driver for all possible rings (all asics).
543  * start the fence driver on the rings it has using
554  * fence driver interrupts need to be restored.
589  * amdgpu_fence_driver_hw_fini - tear down the fence driver
594  * Tear down the fence driver for all possible rings (all asics).
671  * amdgpu_fence_driver_hw_init - enable the fence driver
676  * Enable the fence driver for all possible rings (all asics).
678  * start the fence driver on the rings it has using
703  * @ring: fence of the ring to be cleared
744 		struct dma_fence *fence;  in amdgpu_fence_driver_set_error()  local
746 		fence = rcu_dereference_protected(drv->fences[i],  in amdgpu_fence_driver_set_error()
748 		if (fence && !dma_fence_is_signaled_locked(fence))  in amdgpu_fence_driver_set_error()
749 			dma_fence_set_error(fence, error);  in amdgpu_fence_driver_set_error()
755  * amdgpu_fence_driver_force_completion - force signal latest fence of ring
757  * @ring: fence of the ring to signal
768  * Common fence implementation
771 static const char *amdgpu_fence_get_driver_name(struct dma_fence *fence)  in amdgpu_fence_get_driver_name()  argument
789  * amdgpu_fence_enable_signaling - enable signalling on fence
790  * @f: fence
793  * to fence_queue that checks if this fence is signaled, and if so it
794  * signals the fence and removes itself.
805  * amdgpu_job_fence_enable_signaling - enable signalling on job fence
806  * @f: fence
809  * only handles the job embedded fence.
822  * amdgpu_fence_free - free up the fence memory
826  * Free up the fence memory after the RCU grace period.
832 	/* free fence_slab if it's separated fence*/  in amdgpu_fence_free()
837  * amdgpu_job_fence_free - free up the job with embedded fence
841  * Free up the job with embedded fence after the RCU grace period.
847 	/* free job if fence has a parent job */  in amdgpu_job_fence_free()
852  * amdgpu_fence_release - callback that fence can be freed
854  * @f: fence
857  * It just RCU schedules freeing up the fence.
865  * amdgpu_job_fence_release - callback that job embedded fence can be freed
867  * @f: fence
870  * only handles the job embedded fence.
892  * Fence debugfs
909 		seq_printf(m, "Last signaled fence          0x%08x\n",  in amdgpu_debugfs_fence_info_show()
916 			seq_printf(m, "Last signaled trailing fence 0x%08x\n",  in amdgpu_debugfs_fence_info_show()
941  * Manually trigger a gpu reset at the next fence wait.