ASoC: SOF: Intel: hda: Implement get_stream_position (Linear Link Position)

When the Linear Link Position is not available in firmware SRAM window we
use the host accessible position registers to read it.
The address of the PPLCLLPL/U registers depend on the number of streams
(playback+capture).
At probe time the pplc_addr is calculated for each stream and we can use
it to read the LLP without the need of address re-calculation.

Set the get_stream_position callback in sof_hda_common_ops for all
platforms:
The callback is used for IPC4 delay calculations only but the register is
a generic HDA register, not tied to any specific IPC version.

Cc: stable@vger.kernel.org # 6.8
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://msgid.link/r/20240321130814.4412-5-peter.ujfalusi@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/sound/soc/sof/intel/hda-common-ops.c b/sound/soc/sof/intel/hda-common-ops.c
index 2b385cddc385c5bd59e11acfe8e6bda45704fdd1..80a69599a8c305c8247b996146a00c046730bdac 100644 (file)
--- a/sound/soc/sof/intel/hda-common-ops.c
+++ b/sound/soc/sof/intel/hda-common-ops.c
@@ -57,6 +57,8 @@ struct snd_sof_dsp_ops sof_hda_common_ops = {
        .pcm_pointer    = hda_dsp_pcm_pointer,
        .pcm_ack        = hda_dsp_pcm_ack,
 
+       .get_stream_position = hda_dsp_get_stream_llp,
+
        /* firmware loading */
        .load_firmware = snd_sof_load_firmware_raw,
 

diff --git a/sound/soc/sof/intel/hda-stream.c b/sound/soc/sof/intel/hda-stream.c
index b387b1a69d7ea3ceaed9fe814b174d9040e3eae1..48ea187f72302d7a39928662ee2fc5cd9eafda29 100644 (file)
--- a/sound/soc/sof/intel/hda-stream.c
+++ b/sound/soc/sof/intel/hda-stream.c
@@ -1063,3 +1063,35 @@ snd_pcm_uframes_t hda_dsp_stream_get_position(struct hdac_stream *hstream,
 
        return pos;
 }
+
+/**
+ * hda_dsp_get_stream_llp - Retrieve the LLP (Linear Link Position) of the stream
+ * @sdev: SOF device
+ * @component: ASoC component
+ * @substream: PCM substream
+ *
+ * Returns the raw Linear Link Position value
+ */
+u64 hda_dsp_get_stream_llp(struct snd_sof_dev *sdev,
+                          struct snd_soc_component *component,
+                          struct snd_pcm_substream *substream)
+{
+       struct hdac_stream *hstream = substream->runtime->private_data;
+       struct hdac_ext_stream *hext_stream = stream_to_hdac_ext_stream(hstream);
+       u32 llp_l, llp_u;
+
+       /*
+        * The pplc_addr have been calculated during probe in
+        * hda_dsp_stream_init():
+        * pplc_addr = sdev->bar[HDA_DSP_PP_BAR] +
+        *             SOF_HDA_PPLC_BASE +
+        *             SOF_HDA_PPLC_MULTI * total_stream +
+        *             SOF_HDA_PPLC_INTERVAL * stream_index
+        *
+        * Use this pre-calculated address to avoid repeated re-calculation.
+        */
+       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;
+}

diff --git a/sound/soc/sof/intel/hda.h b/sound/soc/sof/intel/hda.h
index b36eb7c7891335a3038d5e1402d6f73ede754b81..9d26cad785fe059a1ea59ebedd6d158ae08da4f9 100644 (file)
--- a/sound/soc/sof/intel/hda.h
+++ b/sound/soc/sof/intel/hda.h
@@ -662,6 +662,9 @@ bool hda_dsp_check_stream_irq(struct snd_sof_dev *sdev);
 
 snd_pcm_uframes_t hda_dsp_stream_get_position(struct hdac_stream *hstream,
                                              int direction, bool can_sleep);
+u64 hda_dsp_get_stream_llp(struct snd_sof_dev *sdev,
+                          struct snd_soc_component *component,
+                          struct snd_pcm_substream *substream);
 
 struct hdac_ext_stream *
        hda_dsp_stream_get(struct snd_sof_dev *sdev, int direction, u32 flags);