schedule: implement timer driven scheduling

Implements timer driven scheduling by processing
DW DMA data in tasks added to work queue instead
of registering for DW DMA interrupt. Data processing
by default will happen every 1 ms.

Signed-off-by: Tomasz Lauda <tomasz.lauda@linux.intel.com>

Author: tlauda

src/audio/dai.c

@@ -261,6 +261,7 @@ static int dai_playback_params(struct comp_dev *dev)
 	config->src_width = comp_sample_bytes(dev);
 	config->dest_width = comp_sample_bytes(dev);
 	config->cyclic = 1;
+	config->timer_delay = dev->pipeline->ipc_pipe.timer_delay;
 	config->dest_dev = dd->dai->plat_data.fifo[0].handshake;
 
 	/* set up local and host DMA elems to reset values */
@@ -329,6 +330,7 @@ static int dai_capture_params(struct comp_dev *dev)
 	config->src_width = comp_sample_bytes(dev);
 	config->dest_width = comp_sample_bytes(dev);
 	config->cyclic = 1;
+	config->timer_delay = dev->pipeline->ipc_pipe.timer_delay;
 	config->src_dev = dd->dai->plat_data.fifo[1].handshake;
 
 	/* set up local and host DMA elems to reset values */

src/audio/pipeline.c

@@ -219,15 +219,8 @@ static void pipeline_trigger_sched_comp(struct pipeline *p,
 		 */
 		if (comp->params.direction == SOF_IPC_STREAM_PLAYBACK ||
 		    p->status == COMP_STATE_PAUSED) {
-
-			/* pipelines are either scheduled by timers or DAI/DMA interrupts */
-			if (p->ipc_pipe.timer) {
-				/* timer - schedule initial copy */
-				pipeline_schedule_copy(p, 0);
-			} else {
-				/* DAI - schedule initial pipeline fill when next idle */
-				pipeline_schedule_copy_idle(p);
-			}
+			/* schedule initial pipeline fill when next idle */
+			pipeline_schedule_copy_idle(p);
 		}
 		p->status = COMP_STATE_ACTIVE;
 		break;
@@ -1290,11 +1283,6 @@ static void pipeline_task(void *arg)
 
 sched:
 	tracev_pipe("PWe");
-
-	/* now reschedule the task */
-	/* TODO: add in scheduling cost and any timer drift */
-	if (p->ipc_pipe.timer)
-		pipeline_schedule_copy(p, p->ipc_pipe.deadline);
 }
 
 /* init pipeline */