ASoC: SOF: Intel: hda: Create debugfs file to force a clean DSP boot

When IMR boot is supported on a platform it is always going to be used to
boot the DSP unless some catastrophic event happens.
There is no way for a developer to force a clean DSP boot without removing
and re-inserting the modules.

Create a 'skip_imr_boot' debugfs file which can be used to force the
next DSP boot as clean (prune) boot.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://msgid.link/r/20240403105210.17949-2-peter.ujfalusi@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

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

@@ -15,6 +15,7 @@
  * Hardware interface for HDA DSP code loader
  */
 
+#include <linux/debugfs.h>
 #include <linux/firmware.h>
 #include <sound/hdaudio_ext.h>
 #include <sound/hda_register.h>
@@ -643,8 +644,12 @@ int hda_dsp_post_fw_run(struct snd_sof_dev *sdev)
 		/* Check if IMR boot is usable */
 		if (!sof_debug_check_flag(SOF_DBG_IGNORE_D3_PERSISTENT) &&
 		    (sdev->fw_ready.flags & SOF_IPC_INFO_D3_PERSISTENT ||
-		     sdev->pdata->ipc_type == SOF_IPC_TYPE_4))
+		     sdev->pdata->ipc_type == SOF_IPC_TYPE_4)) {
 			hdev->imrboot_supported = true;
+			debugfs_create_bool("skip_imr_boot",
+					    0644, sdev->debugfs_root,
+					    &hdev->skip_imr_boot);
+		}
 	}
 
 	hda_sdw_int_enable(sdev, true);

sound/soc/sof/intel/hda.c

@@ -19,6 +19,7 @@
 #include <sound/hda_register.h>
 
 #include <linux/acpi.h>
+#include <linux/debugfs.h>
 #include <linux/module.h>
 #include <linux/soundwire/sdw.h>
 #include <linux/soundwire/sdw_intel.h>

sound/soc/sof/intel/lnl.c

@@ -6,6 +6,7 @@
  * Hardware interface for audio DSP on LunarLake.
  */
 
+#include <linux/debugfs.h>
 #include <linux/firmware.h>
 #include <sound/hda_register.h>
 #include <sound/sof/ipc4/header.h>
@@ -83,8 +84,12 @@ static int lnl_dsp_post_fw_run(struct snd_sof_dev *sdev)
 		struct sof_intel_hda_dev *hda = sdev->pdata->hw_pdata;
 
 		/* Check if IMR boot is usable */
-		if (!sof_debug_check_flag(SOF_DBG_IGNORE_D3_PERSISTENT))
+		if (!sof_debug_check_flag(SOF_DBG_IGNORE_D3_PERSISTENT)) {
 			hda->imrboot_supported = true;
+			debugfs_create_bool("skip_imr_boot",
+					    0644, sdev->debugfs_root,
+					    &hda->skip_imr_boot);
+		}
 	}
 
 	return 0;

sound/soc/sof/intel/mtl.c

@@ -9,6 +9,7 @@
  * Hardware interface for audio DSP on Meteorlake.
  */
 
+#include <linux/debugfs.h>
 #include <linux/firmware.h>
 #include <sound/sof/ipc4/header.h>
 #include <trace/events/sof_intel.h>
@@ -294,8 +295,12 @@ int mtl_dsp_post_fw_run(struct snd_sof_dev *sdev)
 		}
 
 		/* Check if IMR boot is usable */
-		if (!sof_debug_check_flag(SOF_DBG_IGNORE_D3_PERSISTENT))
+		if (!sof_debug_check_flag(SOF_DBG_IGNORE_D3_PERSISTENT)) {
 			hdev->imrboot_supported = true;
+			debugfs_create_bool("skip_imr_boot",
+					    0644, sdev->debugfs_root,
+					    &hdev->skip_imr_boot);
+		}
 	}
 
 	hda_sdw_int_enable(sdev, true);