ASoC: SOF: Intel: hda-mlink: add helper to program SoundWire PCMSyCM registers

These registers enable the HDaudio DMA hardware to split/merge data
from different PDIs, possibly on different links.

This capability exists for all types of HDaudio extended links, but
for now is only required for SoundWire. In the SSP/DMIC case, the IP
is programmed by the DSP firmware.

Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com
Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com
Reviewed-by: Rander Wang <rander.wang@intel.com
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com
Link: https://lore.kernel.org/r/20230512174611.84372-7-pierre-louis.bossart@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org

include/sound/hda-mlink.h

@@ -44,6 +44,9 @@ int hdac_bus_eml_sdw_power_down_unlocked(struct hdac_bus *bus, int sublink);
 
 int hdac_bus_eml_sdw_set_lsdiid(struct hdac_bus *bus, int sublink, int dev_num);
 
+int hdac_bus_eml_sdw_map_stream_ch(struct hdac_bus *bus, int sublink, int y,
+				   int channel_mask, int stream_id, int dir);
+
 void hda_bus_ml_put_all(struct hdac_bus *bus);
 void hda_bus_ml_reset_losidv(struct hdac_bus *bus);
 int hda_bus_ml_resume(struct hdac_bus *bus);
@@ -145,6 +148,13 @@ hdac_bus_eml_sdw_power_down_unlocked(struct hdac_bus *bus, int sublink) { return
 static inline int
 hdac_bus_eml_sdw_set_lsdiid(struct hdac_bus *bus, int sublink, int dev_num) { return 0; }
 
+static inline int
+hdac_bus_eml_sdw_map_stream_ch(struct hdac_bus *bus, int sublink, int y,
+			       int channel_mask, int stream_id, int dir)
+{
+	return 0;
+}
+
 static inline void hda_bus_ml_put_all(struct hdac_bus *bus) { }
 static inline void hda_bus_ml_reset_losidv(struct hdac_bus *bus) { }
 static inline int hda_bus_ml_resume(struct hdac_bus *bus) { return 0; }

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

@@ -73,6 +73,7 @@ struct hdac_ext2_link {
 #define AZX_REG_SDW_SHIM_OFFSET				0x0
 #define AZX_REG_SDW_IP_OFFSET				0x100
 #define AZX_REG_SDW_VS_SHIM_OFFSET			0x6000
+#define AZX_REG_SDW_SHIM_PCMSyCM(y)			(0x16 + 0x4 * (y))
 
 /* only one instance supported */
 #define AZX_REG_INTEL_DMIC_SHIM_OFFSET			0x0
@@ -340,6 +341,21 @@ static void hdaml_link_set_lsdiid(u32 __iomem *lsdiid, int dev_num)
 	writel(val, lsdiid);
 }
 
+static void hdaml_shim_map_stream_ch(u16 __iomem *pcmsycm, int lchan, int hchan,
+				     int stream_id, int dir)
+{
+	u16 val;
+
+	val = readw(pcmsycm);
+
+	u16p_replace_bits(&val, lchan, GENMASK(3, 0));
+	u16p_replace_bits(&val, hchan, GENMASK(7, 4));
+	u16p_replace_bits(&val, stream_id, GENMASK(13, 8));
+	u16p_replace_bits(&val, dir, BIT(15));
+
+	writew(val, pcmsycm);
+}
+
 static void hdaml_lctl_offload_enable(u32 __iomem *lctl, bool enable)
 {
 	u32 val = readl(lctl);
@@ -756,6 +772,40 @@ int hdac_bus_eml_sdw_set_lsdiid(struct hdac_bus *bus, int sublink, int dev_num)
 	return 0;
 } EXPORT_SYMBOL_NS(hdac_bus_eml_sdw_set_lsdiid, SND_SOC_SOF_HDA_MLINK);
 
+/*
+ * the 'y' parameter comes from the PCMSyCM hardware register naming. 'y' refers to the
+ * PDI index, i.e. the FIFO used for RX or TX
+ */
+int hdac_bus_eml_sdw_map_stream_ch(struct hdac_bus *bus, int sublink, int y,
+				   int channel_mask, int stream_id, int dir)
+{
+	struct hdac_ext2_link *h2link;
+	u16 __iomem *pcmsycm;
+	u16 val;
+
+	h2link = find_ext2_link(bus, true, AZX_REG_ML_LEPTR_ID_SDW);
+	if (!h2link)
+		return -ENODEV;
+
+	pcmsycm = h2link->base_ptr + h2link->shim_offset +
+		h2link->instance_offset * sublink +
+		AZX_REG_SDW_SHIM_PCMSyCM(y);
+
+	mutex_lock(&h2link->eml_lock);
+
+	hdaml_shim_map_stream_ch(pcmsycm, 0, hweight32(channel_mask),
+				 stream_id, dir);
+
+	mutex_unlock(&h2link->eml_lock);
+
+	val = readw(pcmsycm);
+
+	dev_dbg(bus->dev, "channel_mask %#x stream_id %d dir %d pcmscm %#x\n",
+		channel_mask, stream_id, dir, val);
+
+	return 0;
+} EXPORT_SYMBOL_NS(hdac_bus_eml_sdw_map_stream_ch, SND_SOC_SOF_HDA_MLINK);
+
 void hda_bus_ml_put_all(struct hdac_bus *bus)
 {
 	struct hdac_ext_link *hlink;