ASoC: SOF: Add one more state for DMA trace

Currently DMA trace has only 2 states: enabled or disabled.
However DMA trace may have more states. For example, enabled but
not started.

This patch refines the dma trace to provide a mechanism to store
more states than enabled/disabled and adds SOF_DTRACE_STOPPED state.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Signed-off-by: Libin Yang <libin.yang@intel.com>

Author: libinyang

sound/soc/sof/pm.c

@@ -149,8 +149,8 @@ static int sof_resume(struct device *dev, bool runtime_resume)
 		return ret;
 	}
 
-	/* resume DMA trace, only need send ipc */
-	ret = snd_sof_init_trace_ipc(sdev);
+	/* resume DMA trace */
+	ret = snd_sof_trace_resume(sdev);
 	if (ret < 0) {
 		/* non fatal */
 		dev_warn(sdev->dev,
@@ -220,8 +220,8 @@ static int sof_suspend(struct device *dev, bool runtime_suspend)
 
 	sof_tear_down_pipelines(sdev, false);
 
-	/* release trace */
-	snd_sof_release_trace(sdev);
+	/* suspend DMA trace */
+	snd_sof_trace_suspend(sdev, SOF_DSP_PM_D3);
 
 	/* Notify clients not managed by pm framework about core suspend */
 	sof_suspend_clients(sdev, pm_state);

sound/soc/sof/sof-priv.h

@@ -374,6 +374,12 @@ struct snd_sof_ipc {
 	struct snd_sof_ipc_msg msg;
 };
 
+enum sof_dtrace_state {
+	SOF_DTRACE_DISABLED,
+	SOF_DTRACE_STOPPED,
+	SOF_DTRACE_ENABLED,
+};
+
 /*
  * SOF Device Level.
  */
@@ -461,9 +467,9 @@ struct snd_sof_dev {
 	wait_queue_head_t trace_sleep;
 	u32 host_offset;
 	bool dtrace_is_supported; /* set with Kconfig or module parameter */
-	bool dtrace_is_enabled;
 	bool dtrace_error;
 	bool dtrace_draining;
+	enum sof_dtrace_state dtrace_state;
 
 	bool msi_enabled;
 
@@ -568,7 +574,6 @@ static inline void snd_sof_ipc_process_reply(struct snd_sof_dev *sdev, u32 msg_i
  * Trace/debug
  */
 int snd_sof_init_trace(struct snd_sof_dev *sdev);
-void snd_sof_release_trace(struct snd_sof_dev *sdev);
 void snd_sof_free_trace(struct snd_sof_dev *sdev);
 int snd_sof_dbg_init(struct snd_sof_dev *sdev);
 void snd_sof_free_debug(struct snd_sof_dev *sdev);
@@ -582,7 +587,8 @@ void sof_print_oops_and_stack(struct snd_sof_dev *sdev, const char *level,
 			      u32 panic_code, u32 tracep_code, void *oops,
 			      struct sof_ipc_panic_info *panic_info,
 			      void *stack, size_t stack_words);
-int snd_sof_init_trace_ipc(struct snd_sof_dev *sdev);
+int snd_sof_trace_suspend(struct snd_sof_dev *sdev, int pm_state);
+int snd_sof_trace_resume(struct snd_sof_dev *sdev);
 void snd_sof_handle_fw_exception(struct snd_sof_dev *sdev);
 int snd_sof_dbg_memory_info_init(struct snd_sof_dev *sdev);
 int snd_sof_debugfs_add_region_item_iomem(struct snd_sof_dev *sdev,

sound/soc/sof/trace.c

@@ -11,6 +11,7 @@
 #include <linux/debugfs.h>
 #include <linux/sched/signal.h>
 #include "sof-priv.h"
+#include "sof-audio.h"
 #include "ops.h"
 #include "sof-utils.h"
 
@@ -263,7 +264,7 @@ static size_t sof_wait_trace_avail(struct snd_sof_dev *sdev,
 	if (ret)
 		return ret;
 
-	if (!sdev->dtrace_is_enabled && sdev->dtrace_draining) {
+	if (sdev->dtrace_state != SOF_DTRACE_ENABLED && sdev->dtrace_draining) {
 		/*
 		 * tracing has ended and all traces have been
 		 * read by client, return EOF
@@ -337,7 +338,7 @@ static int sof_dfsentry_trace_release(struct inode *inode, struct file *file)
 	struct snd_sof_dev *sdev = dfse->sdev;
 
 	/* avoid duplicate traces at next open */
-	if (!sdev->dtrace_is_enabled)
+	if (sdev->dtrace_state != SOF_DTRACE_ENABLED)
 		sdev->host_offset = 0;
 
 	return 0;
@@ -377,7 +378,7 @@ static int trace_debugfs_create(struct snd_sof_dev *sdev)
 	return 0;
 }
 
-int snd_sof_init_trace_ipc(struct snd_sof_dev *sdev)
+static int snd_sof_enable_trace(struct snd_sof_dev *sdev)
 {
 	struct sof_ipc_fw_ready *ready = &sdev->fw_ready;
 	struct sof_ipc_fw_version *v = &ready->version;
@@ -388,9 +389,12 @@ int snd_sof_init_trace_ipc(struct snd_sof_dev *sdev)
 	if (!sdev->dtrace_is_supported)
 		return 0;
 
-	if (sdev->dtrace_is_enabled || !sdev->dma_trace_pages)
+	if (sdev->dtrace_state == SOF_DTRACE_ENABLED || !sdev->dma_trace_pages)
 		return -EINVAL;
 
+	if (sdev->dtrace_state == SOF_DTRACE_STOPPED)
+		goto start;
+
 	/* set IPC parameters */
 	params.hdr.cmd = SOF_IPC_GLB_TRACE_MSG;
 	/* PARAMS_EXT is only supported from ABI 3.7.0 onwards */
@@ -428,14 +432,15 @@ int snd_sof_init_trace_ipc(struct snd_sof_dev *sdev)
 		goto trace_release;
 	}
 
+start:
 	ret = snd_sof_dma_trace_trigger(sdev, SNDRV_PCM_TRIGGER_START);
 	if (ret < 0) {
 		dev_err(sdev->dev,
 			"error: snd_sof_dma_trace_trigger: start: %d\n", ret);
 		goto trace_release;
 	}
 
-	sdev->dtrace_is_enabled = true;
+	sdev->dtrace_state = SOF_DTRACE_ENABLED;
 
 	return 0;
 
@@ -452,7 +457,7 @@ int snd_sof_init_trace(struct snd_sof_dev *sdev)
 		return 0;
 
 	/* set false before start initialization */
-	sdev->dtrace_is_enabled = false;
+	sdev->dtrace_state = SOF_DTRACE_DISABLED;
 
 	/* allocate trace page table buffer */
 	ret = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, sdev->dev,
@@ -490,7 +495,7 @@ int snd_sof_init_trace(struct snd_sof_dev *sdev)
 
 	init_waitqueue_head(&sdev->trace_sleep);
 
-	ret = snd_sof_init_trace_ipc(sdev);
+	ret = snd_sof_enable_trace(sdev);
 	if (ret < 0)
 		goto table_err;
 
@@ -510,7 +515,8 @@ int snd_sof_trace_update_pos(struct snd_sof_dev *sdev,
 	if (!sdev->dtrace_is_supported)
 		return 0;
 
-	if (sdev->dtrace_is_enabled && sdev->host_offset != posn->host_offset) {
+	if (sdev->dtrace_state == SOF_DTRACE_ENABLED &&
+	    sdev->host_offset != posn->host_offset) {
 		sdev->host_offset = posn->host_offset;
 		wake_up(&sdev->trace_sleep);
 	}
@@ -529,28 +535,29 @@ void snd_sof_trace_notify_for_error(struct snd_sof_dev *sdev)
 	if (!sdev->dtrace_is_supported)
 		return;
 
-	if (sdev->dtrace_is_enabled) {
+	if (sdev->dtrace_state == SOF_DTRACE_ENABLED) {
 		sdev->dtrace_error = true;
 		wake_up(&sdev->trace_sleep);
 	}
 }
 EXPORT_SYMBOL(snd_sof_trace_notify_for_error);
 
-void snd_sof_release_trace(struct snd_sof_dev *sdev)
+static void snd_sof_release_trace(struct snd_sof_dev *sdev, bool only_stop)
 {
 	struct sof_ipc_fw_ready *ready = &sdev->fw_ready;
 	struct sof_ipc_fw_version *v = &ready->version;
 	struct sof_ipc_cmd_hdr hdr;
 	struct sof_ipc_reply ipc_reply;
 	int ret;
 
-	if (!sdev->dtrace_is_supported || !sdev->dtrace_is_enabled)
+	if (!sdev->dtrace_is_supported || sdev->dtrace_state == SOF_DTRACE_DISABLED)
 		return;
 
 	ret = snd_sof_dma_trace_trigger(sdev, SNDRV_PCM_TRIGGER_STOP);
 	if (ret < 0)
 		dev_err(sdev->dev,
 			"error: snd_sof_dma_trace_trigger: stop: %d\n", ret);
+	sdev->dtrace_state = SOF_DTRACE_STOPPED;
 
 	/*
 	 * stop and free trace DMA in the DSP. TRACE_DMA_FREE is only supported from
@@ -566,23 +573,46 @@ void snd_sof_release_trace(struct snd_sof_dev *sdev)
 			dev_err(sdev->dev, "DMA_TRACE_FREE failed with error: %d\n", ret);
 	}
 
+	if (only_stop)
+		goto out;
+
 	ret = snd_sof_dma_trace_release(sdev);
 	if (ret < 0)
 		dev_err(sdev->dev,
 			"error: fail in snd_sof_dma_trace_release %d\n", ret);
 
-	sdev->dtrace_is_enabled = false;
+	sdev->dtrace_state = SOF_DTRACE_DISABLED;
+
+out:
 	sdev->dtrace_draining = true;
 	wake_up(&sdev->trace_sleep);
 }
-EXPORT_SYMBOL(snd_sof_release_trace);
+
+int snd_sof_trace_suspend(struct snd_sof_dev *sdev, int pm_state)
+{
+	if (pm_state == SOF_DSP_PM_D0)
+		snd_sof_release_trace(sdev, 1);
+	else
+		snd_sof_release_trace(sdev, 0);
+
+	/* always return 0 */
+	return 0;
+}
+EXPORT_SYMBOL(snd_sof_trace_suspend);
+
+int snd_sof_trace_resume(struct snd_sof_dev *sdev)
+{
+	return snd_sof_enable_trace(sdev);
+}
+EXPORT_SYMBOL(snd_sof_trace_resume);
 
 void snd_sof_free_trace(struct snd_sof_dev *sdev)
 {
 	if (!sdev->dtrace_is_supported)
 		return;
 
-	snd_sof_release_trace(sdev);
+	/* release trace */
+	snd_sof_release_trace(sdev, 0);
 
 	if (sdev->dma_trace_pages) {
 		snd_dma_free_pages(&sdev->dmatb);