6.8-stable review patch. If anyone has any objections, please let me know.
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From: Peter Ujfalusi peter.ujfalusi@linux.intel.com
commit 1abc2642588e06f6180b3fbb21968cf5d0ba9e5f 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 --- sound/soc/sof/intel/hda-dai-ops.c | 11 +++++++++++ sound/soc/sof/intel/hda-pcm.c | 8 ++++++++ sound/soc/sof/intel/hda-stream.c | 9 ++++++++- 3 files changed, 27 insertions(+), 1 deletion(-)
--- a/sound/soc/sof/intel/hda-dai-ops.c +++ b/sound/soc/sof/intel/hda-dai-ops.c @@ -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_de 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); --- a/sound/soc/sof/intel/hda-pcm.c +++ b/sound/soc/sof/intel/hda-pcm.c @@ -282,6 +282,14 @@ int hda_dsp_pcm_open(struct snd_sof_dev
/* 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; }
--- a/sound/soc/sof/intel/hda-stream.c +++ b/sound/soc/sof/intel/hda-stream.c @@ -1055,6 +1055,8 @@ snd_pcm_uframes_t hda_dsp_stream_get_pos 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_so 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); }
/**