ASoC: SOF: Intel: hda: enable DMI L1 for D0i3-compatible streams

DMI L1 entry is currently disabled whenever any capture stream is
opened to prevent xruns during pause/release. But, in
order to maximise power savings for the wake-on-voice usecase,
DMI L1 entry should be enabled for D0i3-compatible capture streams.
Introduce a new field, flags in struct sof_intel_hda_stream
that stores whether a stream is dmi_l1_compatible. All playback streams,
and D0i3-compatible capture streams are DMI L1 compatible.
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Link: https://lore.kernel.org/r/20210127020737.1088960-2-ranjani.sridharan@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/sof/intel/hda-compress.c

@@ -25,7 +25,7 @@ int hda_probe_compr_assign(struct snd_sof_dev *sdev,
 {
 	struct hdac_ext_stream *stream;
 
-	stream = hda_dsp_stream_get(sdev, cstream->direction);
+	stream = hda_dsp_stream_get(sdev, cstream->direction, 0);
 	if (!stream)
 		return -EBUSY;
 

sound/soc/sof/intel/hda-loader.c

@@ -35,7 +35,7 @@ static struct hdac_ext_stream *cl_stream_prepare(struct snd_sof_dev *sdev, unsig
 	struct pci_dev *pci = to_pci_dev(sdev->dev);
 	int ret;
 
-	dsp_stream = hda_dsp_stream_get(sdev, direction);
+	dsp_stream = hda_dsp_stream_get(sdev, direction, 0);
 
 	if (!dsp_stream) {
 		dev_err(sdev->dev, "error: no stream available\n");

sound/soc/sof/intel/hda-pcm.c

@@ -215,11 +215,25 @@ snd_pcm_uframes_t hda_dsp_pcm_pointer(struct snd_sof_dev *sdev,
 int hda_dsp_pcm_open(struct snd_sof_dev *sdev,
 		     struct snd_pcm_substream *substream)
 {
+	struct snd_soc_pcm_runtime *rtd = asoc_substream_to_rtd(substream);
+	struct snd_soc_component *scomp = sdev->component;
 	struct hdac_ext_stream *dsp_stream;
+	struct snd_sof_pcm *spcm;
 	int direction = substream->stream;
+	u32 flags = 0;
+
+	spcm = snd_sof_find_spcm_dai(scomp, rtd);
+	if (!spcm) {
+		dev_err(sdev->dev, "error: can't find PCM with DAI ID %d\n", rtd->dai_link->id);
+		return -EINVAL;
+	}
 
-	dsp_stream = hda_dsp_stream_get(sdev, direction);
+	/* All playback and D0i3 compatible streams are DMI L1 capable */
+	if (direction == SNDRV_PCM_STREAM_PLAYBACK ||
+	    spcm->stream[substream->stream].d0i3_compatible)
+		flags |= SOF_HDA_STREAM_DMI_L1_COMPATIBLE;
 
+	dsp_stream = hda_dsp_stream_get(sdev, direction, flags);
 	if (!dsp_stream) {
 		dev_err(sdev->dev, "error: no stream available\n");
 		return -ENODEV;

sound/soc/sof/intel/hda-stream.c

@@ -155,7 +155,7 @@ int hda_dsp_stream_spib_config(struct snd_sof_dev *sdev,
 
 /* get next unused stream */
 struct hdac_ext_stream *
-hda_dsp_stream_get(struct snd_sof_dev *sdev, int direction)
+hda_dsp_stream_get(struct snd_sof_dev *sdev, int direction, u32 flags)
 {
 	struct hdac_bus *bus = sof_to_bus(sdev);
 	struct sof_intel_hda_stream *hda_stream;
@@ -183,18 +183,22 @@ hda_dsp_stream_get(struct snd_sof_dev *sdev, int direction)
 	spin_unlock_irq(&bus->reg_lock);
 
 	/* stream found ? */
-	if (!stream)
+	if (!stream) {
 		dev_err(sdev->dev, "error: no free %s streams\n",
 			direction == SNDRV_PCM_STREAM_PLAYBACK ?
 			"playback" : "capture");
+		return stream;
+	}
+
+	hda_stream->flags = flags;
 
 	/*
-	 * Disable DMI Link L1 entry when capture stream is opened.
+	 * Prevent DMI Link L1 entry for streams that don't support it.
 	 * Workaround to address a known issue with host DMA that results
 	 * in xruns during pause/release in capture scenarios.
 	 */
 	if (!IS_ENABLED(CONFIG_SND_SOC_SOF_HDA_ALWAYS_ENABLE_DMI_L1))
-		if (stream && direction == SNDRV_PCM_STREAM_CAPTURE)
+		if (stream && !(flags & SOF_HDA_STREAM_DMI_L1_COMPATIBLE))
 			snd_sof_dsp_update_bits(sdev, HDA_DSP_HDA_BAR,
 						HDA_VS_INTEL_EM2,
 						HDA_VS_INTEL_EM2_L1SEN, 0);
@@ -206,37 +210,39 @@ hda_dsp_stream_get(struct snd_sof_dev *sdev, int direction)
 int hda_dsp_stream_put(struct snd_sof_dev *sdev, int direction, int stream_tag)
 {
 	struct hdac_bus *bus = sof_to_bus(sdev);
+	struct sof_intel_hda_stream *hda_stream;
+	struct hdac_ext_stream *stream;
 	struct hdac_stream *s;
-	bool active_capture_stream = false;
+	bool dmi_l1_enable = true;
 	bool found = false;
 
 	spin_lock_irq(&bus->reg_lock);
 
 	/*
-	 * close stream matching the stream tag
-	 * and check if there are any open capture streams.
+	 * close stream matching the stream tag and check if there are any open streams
+	 * that are DMI L1 incompatible.
 	 */
 	list_for_each_entry(s, &bus->stream_list, list) {
+		stream = stream_to_hdac_ext_stream(s);
+		hda_stream = container_of(stream, struct sof_intel_hda_stream, hda_stream);
+
 		if (!s->opened)
 			continue;
 
 		if (s->direction == direction && s->stream_tag == stream_tag) {
 			s->opened = false;
 			found = true;
-		} else if (s->direction == SNDRV_PCM_STREAM_CAPTURE) {
-			active_capture_stream = true;
+		} else if (!(hda_stream->flags & SOF_HDA_STREAM_DMI_L1_COMPATIBLE)) {
+			dmi_l1_enable = false;
 		}
 	}
 
 	spin_unlock_irq(&bus->reg_lock);
 
-	/* Enable DMI L1 entry if there are no capture streams open */
-	if (!IS_ENABLED(CONFIG_SND_SOC_SOF_HDA_ALWAYS_ENABLE_DMI_L1))
-		if (!active_capture_stream)
-			snd_sof_dsp_update_bits(sdev, HDA_DSP_HDA_BAR,
-						HDA_VS_INTEL_EM2,
-						HDA_VS_INTEL_EM2_L1SEN,
-						HDA_VS_INTEL_EM2_L1SEN);
+	/* Enable DMI L1 if permitted */
+	if (!IS_ENABLED(CONFIG_SND_SOC_SOF_HDA_ALWAYS_ENABLE_DMI_L1) && dmi_l1_enable)
+		snd_sof_dsp_update_bits(sdev, HDA_DSP_HDA_BAR, HDA_VS_INTEL_EM2,
+					HDA_VS_INTEL_EM2_L1SEN, HDA_VS_INTEL_EM2_L1SEN);
 
 	if (!found) {
 		dev_dbg(sdev->dev, "stream_tag %d not opened!\n", stream_tag);

sound/soc/sof/intel/hda-trace.c

@@ -42,8 +42,7 @@ int hda_dsp_trace_init(struct snd_sof_dev *sdev, u32 *stream_tag)
 	struct sof_intel_hda_dev *hda = sdev->pdata->hw_pdata;
 	int ret;
 
-	hda->dtrace_stream = hda_dsp_stream_get(sdev,
-						SNDRV_PCM_STREAM_CAPTURE);
+	hda->dtrace_stream = hda_dsp_stream_get(sdev, SNDRV_PCM_STREAM_CAPTURE, 0);
 
 	if (!hda->dtrace_stream) {
 		dev_err(sdev->dev,

sound/soc/sof/intel/hda.h

@@ -402,6 +402,9 @@ struct sof_intel_dsp_bdl {
 #define SOF_HDA_PLAYBACK		0
 #define SOF_HDA_CAPTURE			1
 
+/* stream flags */
+#define SOF_HDA_STREAM_DMI_L1_COMPATIBLE	1
+
 /*
  * Time in ms for opportunistic D0I3 entry delay.
  * This has been deliberately chosen to be long to avoid race conditions.
@@ -471,6 +474,7 @@ struct sof_intel_hda_stream {
 	struct hdac_ext_stream hda_stream;
 	struct sof_intel_stream stream;
 	int host_reserved; /* reserve host DMA channel */
+	u32 flags;
 };
 
 #define hstream_to_sof_hda_stream(hstream) \
@@ -562,7 +566,7 @@ bool hda_dsp_check_ipc_irq(struct snd_sof_dev *sdev);
 bool hda_dsp_check_stream_irq(struct snd_sof_dev *sdev);
 
 struct hdac_ext_stream *
-	hda_dsp_stream_get(struct snd_sof_dev *sdev, int direction);
+	hda_dsp_stream_get(struct snd_sof_dev *sdev, int direction, u32 flags);
 int hda_dsp_stream_put(struct snd_sof_dev *sdev, int direction, int stream_tag);
 int hda_dsp_stream_spib_config(struct snd_sof_dev *sdev,
 			       struct hdac_ext_stream *stream,