ASoC: SOF: Intel: mtl: Implement firmware boot state check

With the corrected rom_status_reg values we can now add a check for target
boot status for firmware booting.
With the check now we can identify failed firmware boots (IMR boots) and
we can use the fallback to purge boot the DSP.

Fixes: 064520e8 ("ASoC: SOF: Intel: Add support for MeteorLake (MTL)")
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Reviewed-by: Rander Wang <rander.wang@intel.com>
Reviewed-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Liam Girdwood <liam.r.girdwood@intel.com>
Link: https://msgid.link/r/20240403105210.17949-6-peter.ujfalusi@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/sof/intel/mtl.c

@@ -444,7 +444,7 @@ int mtl_dsp_cl_init(struct snd_sof_dev *sdev, int stream_tag, bool imr_boot)
 {
 	struct sof_intel_hda_dev *hda = sdev->pdata->hw_pdata;
 	const struct sof_intel_dsp_desc *chip = hda->desc;
-	unsigned int status;
+	unsigned int status, target_status;
 	u32 ipc_hdr, flags;
 	char *dump_msg;
 	int ret;
@@ -490,13 +490,40 @@ int mtl_dsp_cl_init(struct snd_sof_dev *sdev, int stream_tag, bool imr_boot)
 
 	mtl_enable_ipc_interrupts(sdev);
 
+	if (chip->rom_status_reg == MTL_DSP_ROM_STS) {
+		/*
+		 * Workaround: when the ROM status register is pointing to
+		 * the SRAM window (MTL_DSP_ROM_STS) the platform cannot catch
+		 * ROM_INIT_DONE because of a very short timing window.
+		 * Follow the recommendations and skip target state waiting.
+		 */
+		return 0;
+	}
+
 	/*
-	 * ACE workaround: don't wait for ROM INIT.
-	 * The platform cannot catch ROM_INIT_DONE because of a very short
-	 * timing window. Follow the recommendations and skip this part.
+	 * step 7:
+	 * - Cold/Full boot: wait for ROM init to proceed to download the firmware
+	 * - IMR boot: wait for ROM firmware entered (firmware booted up from IMR)
 	 */
+	if (imr_boot)
+		target_status = FSR_STATE_FW_ENTERED;
+	else
+		target_status = FSR_STATE_INIT_DONE;
 
-	return 0;
+	ret = snd_sof_dsp_read_poll_timeout(sdev, HDA_DSP_BAR,
+					chip->rom_status_reg, status,
+					(FSR_TO_STATE_CODE(status) == target_status),
+					HDA_DSP_REG_POLL_INTERVAL_US,
+					chip->rom_init_timeout *
+					USEC_PER_MSEC);
+
+	if (!ret)
+		return 0;
+
+	if (hda->boot_iteration == HDA_FW_BOOT_ATTEMPTS)
+		dev_err(sdev->dev,
+			"%s: timeout with rom_status_reg (%#x) read\n",
+			__func__, chip->rom_status_reg);
 
 err:
 	flags = SOF_DBG_DUMP_PCI | SOF_DBG_DUMP_MBOX | SOF_DBG_DUMP_OPTIONAL;