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ASoC: SOF: Intel: hda-pcm: Use dsp_max_burst_size_in_ms to place constraint

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If the PCM have the dsp_max_burst_size_in_ms set then place a constraint
to limit the minimum buffer time to avoid xruns caused by DMA bursts
spinning on the ALSA buffer.

Cc: stable@vger.kernel.org # 6.8
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://msgid.link/r/20240321130814.4412-4-peter.ujfalusi@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Peter Ujfalusi 2024-03-21 15:08:00 +02:00 committed by Mark Brown
parent 842bb8b62c
commit fe76d2e75a
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GPG Key ID: 24D68B725D5487D0
1 changed files with 21 additions and 0 deletions
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21
sound/soc/sof/intel/hda-pcm.c
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@ -259,6 +259,27 @@ int hda_dsp_pcm_open(struct snd_sof_dev *sdev,
snd_pcm_hw_constraint_mask64(substream->runtime, SNDRV_PCM_HW_PARAM_FORMAT,
SNDRV_PCM_FMTBIT_S16 | SNDRV_PCM_FMTBIT_S32);
/*
* The dsp_max_burst_size_in_ms is the length of the maximum burst size
* of the host DMA in the ALSA buffer.
*
* On playback start the DMA will transfer dsp_max_burst_size_in_ms
* amount of data in one initial burst to fill up the host DMA buffer.
* Consequent DMA burst sizes are shorter and their length can vary.
* To make sure that userspace allocate large enough ALSA buffer we need
* to place a constraint on the buffer time.
*
* On capture the DMA will transfer 1ms chunks.
*
* Exact dsp_max_burst_size_in_ms constraint is racy, so set the
* constraint to a minimum of 2x dsp_max_burst_size_in_ms.
*/
if (spcm->stream[direction].dsp_max_burst_size_in_ms)
snd_pcm_hw_constraint_minmax(substream->runtime,
SNDRV_PCM_HW_PARAM_BUFFER_TIME,
spcm->stream[direction].dsp_max_burst_size_in_ms * USEC_PER_MSEC * 2,
UINT_MAX);
/* binding pcm substream to hda stream */
substream->runtime->private_data = &dsp_stream->hstream;
return 0;