ASoC: SOF: amd: Handle IPC replies before FW_BOOT_COMPLETE

In some cases, e.g. during resuming from suspend, there is a possibility
that some IPC reply messages get received by the host while the DSP
firmware has not yet reached the complete boot state.

Detect when this happens and do not attempt to process the unexpected
replies from DSP.  Instead, provide proper debugging support.

Signed-off-by: Cristian Ciocaltea <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Mark Brown <[email protected]>

Author: cristicc

sound/soc/sof/amd/acp-ipc.c

@@ -167,6 +167,7 @@ irqreturn_t acp_sof_ipc_irq_thread(int irq, void *context)
 
 	if (sdev->first_boot && sdev->fw_state != SOF_FW_BOOT_COMPLETE) {
 		acp_mailbox_read(sdev, sdev->dsp_box.offset, &status, sizeof(status));
+
 		if ((status & SOF_IPC_PANIC_MAGIC_MASK) == SOF_IPC_PANIC_MAGIC) {
 			snd_sof_dsp_panic(sdev, sdev->dsp_box.offset + sizeof(status),
 					  true);
@@ -188,13 +189,21 @@ irqreturn_t acp_sof_ipc_irq_thread(int irq, void *context)
 
 	dsp_ack = snd_sof_dsp_read(sdev, ACP_DSP_BAR, ACP_SCRATCH_REG_0 + dsp_ack_write);
 	if (dsp_ack) {
-		spin_lock_irq(&sdev->ipc_lock);
-		/* handle immediate reply from DSP core */
-		acp_dsp_ipc_get_reply(sdev);
-		snd_sof_ipc_reply(sdev, 0);
-		/* set the done bit */
-		acp_dsp_ipc_dsp_done(sdev);
-		spin_unlock_irq(&sdev->ipc_lock);
+		if (likely(sdev->fw_state == SOF_FW_BOOT_COMPLETE)) {
+			spin_lock_irq(&sdev->ipc_lock);
+
+			/* handle immediate reply from DSP core */
+			acp_dsp_ipc_get_reply(sdev);
+			snd_sof_ipc_reply(sdev, 0);
+			/* set the done bit */
+			acp_dsp_ipc_dsp_done(sdev);
+
+			spin_unlock_irq(&sdev->ipc_lock);
+		} else {
+			dev_dbg_ratelimited(sdev->dev, "IPC reply before FW_BOOT_COMPLETE: %#x\n",
+					    dsp_ack);
+		}
+
 		ipc_irq = true;
 	}