ASoC: SOF: Intel: hda: Compensate LLP in case it is not reset

commit 1abc264258 upstream.

During pause/reset or stop/start the LLP counter is not reset, which will
result broken delay reporting.

Read the LLP value on STOP/PAUSE trigger and use it in LLP reading to
normalize the LLP from the register.

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/20240321130814.4412-18-peter.ujfalusi@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Peter Ujfalusi 2024-03-21 15:08:14 +02:00 committed by Greg Kroah-Hartman
parent 75137027f5
commit 7c38be7722
3 changed files with 27 additions and 1 deletions

View File

@ -7,6 +7,7 @@
#include <sound/pcm_params.h>
#include <sound/hdaudio_ext.h>
#include <sound/hda_register.h>
#include <sound/hda-mlink.h>
#include <sound/sof/ipc4/header.h>
#include <uapi/sound/sof/header.h>
@ -362,6 +363,16 @@ static int hda_trigger(struct snd_sof_dev *sdev, struct snd_soc_dai *cpu_dai,
case SNDRV_PCM_TRIGGER_STOP:
case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
snd_hdac_ext_stream_clear(hext_stream);
/*
* Save the LLP registers in case the stream is
* restarting due PAUSE_RELEASE, or START without a pcm
* close/open since in this case the LLP register is not reset
* to 0 and the delay calculation will return with invalid
* results.
*/
hext_stream->pplcllpl = readl(hext_stream->pplc_addr + AZX_REG_PPLCLLPL);
hext_stream->pplcllpu = readl(hext_stream->pplc_addr + AZX_REG_PPLCLLPU);
break;
default:
dev_err(sdev->dev, "unknown trigger command %d\n", cmd);

View File

@ -282,6 +282,14 @@ int hda_dsp_pcm_open(struct snd_sof_dev *sdev,
/* binding pcm substream to hda stream */
substream->runtime->private_data = &dsp_stream->hstream;
/*
* Reset the llp cache values (they are used for LLP compensation in
* case the counter is not reset)
*/
dsp_stream->pplcllpl = 0;
dsp_stream->pplcllpu = 0;
return 0;
}

View File

@ -1055,6 +1055,8 @@ snd_pcm_uframes_t hda_dsp_stream_get_position(struct hdac_stream *hstream,
return pos;
}
#define merge_u64(u32_u, u32_l) (((u64)(u32_u) << 32) | (u32_l))
/**
* hda_dsp_get_stream_llp - Retrieve the LLP (Linear Link Position) of the stream
* @sdev: SOF device
@ -1084,7 +1086,12 @@ u64 hda_dsp_get_stream_llp(struct snd_sof_dev *sdev,
llp_l = readl(hext_stream->pplc_addr + AZX_REG_PPLCLLPL);
llp_u = readl(hext_stream->pplc_addr + AZX_REG_PPLCLLPU);
return ((u64)llp_u << 32) | llp_l;
/* Compensate the LLP counter with the saved offset */
if (hext_stream->pplcllpl || hext_stream->pplcllpu)
return merge_u64(llp_u, llp_l) -
merge_u64(hext_stream->pplcllpu, hext_stream->pplcllpl);
return merge_u64(llp_u, llp_l);
}
/**