ASoC: SOF: add fw_info_box support

FW can share some information with host driver, .e.g fw status, pipeline
status and volume status. On ipc4 platform it is located in memory
windows 0 with size of struct sof_ipc4_fw_reg.

With this patch, ipc4 driver can find fw information in fw_info_box
Signed-off-by: Rander Wang <rander.wang@intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Link: https://lore.kernel.org/r/20230202132954.26773-3-peter.ujfalusi@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/sof/ipc4-priv.h

@@ -14,6 +14,7 @@
 #include "sof-priv.h"
 
 /* The DSP window indices are fixed */
+#define SOF_IPC4_INBOX_WINDOW_IDX	0
 #define SOF_IPC4_OUTBOX_WINDOW_IDX	1
 #define SOF_IPC4_DEBUG_WINDOW_IDX	2
 

sound/soc/sof/ipc4.c

@@ -13,6 +13,7 @@
 #include <sound/sof/ipc4/header.h>
 #include "sof-priv.h"
 #include "sof-audio.h"
+#include "ipc4-fw-reg.h"
 #include "ipc4-priv.h"
 #include "ops.h"
 
@@ -542,6 +543,8 @@ static int ipc4_fw_ready(struct snd_sof_dev *sdev, struct sof_ipc4_msg *ipc4_msg
 	outbox_offset = snd_sof_dsp_get_window_offset(sdev, SOF_IPC4_OUTBOX_WINDOW_IDX);
 	outbox_size = SOF_IPC4_MSG_MAX_SIZE;
 
+	sdev->fw_info_box.offset = snd_sof_dsp_get_window_offset(sdev, SOF_IPC4_INBOX_WINDOW_IDX);
+	sdev->fw_info_box.size = sizeof(struct sof_ipc4_fw_registers);
 	sdev->dsp_box.offset = inbox_offset;
 	sdev->dsp_box.size = inbox_size;
 	sdev->host_box.offset = outbox_offset;

sound/soc/sof/sof-priv.h

@@ -548,6 +548,7 @@ struct snd_sof_dev {
 
 	/* IPC */
 	struct snd_sof_ipc *ipc;
+	struct snd_sof_mailbox fw_info_box;	/* FW shared memory */
 	struct snd_sof_mailbox dsp_box;		/* DSP initiated IPC */
 	struct snd_sof_mailbox host_box;	/* Host initiated IPC */
 	struct snd_sof_mailbox stream_box;	/* Stream position update */