[Sound-open-firmware] [PATCH] APL/CNL Fix: Only send position once after copy DMA trace data on APL/CNL.

[yan.wang at linux.intel.com]

From: Yan Wang <yan.wang at linux.intel.com>

Firmware side should not send position in every trace_work() is called.

Signed-off-by: Yan Wang <yan.wang at linux.intel.com>
---
Test with:
Mininow max rt5651 and APL UP^2 nocodec and CNL nocodec
SOF 1.1-stable: 98d3a838cb397e91d6c032cf9b39d3748102803e
SOF-Tool 1.1-stable: 78ad1ccce5ac689680adc32f8136f5bf551b0f7c
https://github.com/plbossart/sound/tree/topic/sof-v4.14:
c33cfed51fff5eb156dcf70ba849e6ffb3008377
---
 src/include/reef/dma-trace.h | 1 +
 src/lib/dma-trace.c          | 5 ++++-
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/include/reef/dma-trace.h b/src/include/reef/dma-trace.h
index bf6e3f3..c5982d2 100644
--- a/src/include/reef/dma-trace.h
+++ b/src/include/reef/dma-trace.h
@@ -56,6 +56,7 @@ struct dma_trace_data {
 	struct dma_sg_config config;
 	struct dma_trace_buf dmatb;
 	struct dma_copy dc;
+	uint32_t old_host_offset;
 	uint32_t host_offset;
 	uint32_t overflow;
 	uint32_t messages;
diff --git a/src/lib/dma-trace.c b/src/lib/dma-trace.c
index d9adb6d..d7ad3d2 100644
--- a/src/lib/dma-trace.c
+++ b/src/lib/dma-trace.c
@@ -64,7 +64,10 @@ static uint64_t trace_work(void *data, uint64_t delay)
 	 * This function will be called once every 500ms at least even
 	 * if no new trace is filled.
 	 */
-	ipc_dma_trace_send_position();
+	if (d->old_host_offset != d->host_offset) {
+		ipc_dma_trace_send_position();
+		d->old_host_offset = d->host_offset;
+	}
 #endif
 
 	/* any data to copy ? */
-- 
2.14.3