From dc256ce61874b4b90b9417500abb3bbe28c0698d Mon Sep 17 00:00:00 2001
From: Sven-Ola Tuecke <sven-ola@gmx.de>
Date: Fri, 23 Jan 2026 17:30:17 +0100
Subject: [PATCH] Revert "k1x_rproc: avoid creating busy looping mailbox
 threads"

This reverts commit 57803086cdfa1df3b4fd5f66889a1f3649b2e796.
---
 drivers/remoteproc/k1x-rproc.c | 51 +++++++++++++++++++++++++++++-----
 1 file changed, 44 insertions(+), 7 deletions(-)

diff --git a/drivers/remoteproc/k1x-rproc.c b/drivers/remoteproc/k1x-rproc.c
index 36d3d17d4..8d0c318b5 100644
--- a/drivers/remoteproc/k1x-rproc.c
+++ b/drivers/remoteproc/k1x-rproc.c
@@ -12,6 +12,7 @@
 #include <linux/reset.h>
 #include <linux/clk.h>
 #include <linux/clkdev.h>
+#include <linux/kthread.h>
 #include <linux/clk-provider.h>
 #include <linux/mailbox_client.h>
 #include <linux/completion.h>
@@ -57,6 +58,8 @@ struct spacemit_mbox {
 	const char name[10];
 	struct mbox_chan *chan;
 	struct mbox_client client;
+	struct task_struct *mb_thread;
+	bool kthread_running;
 	struct completion mb_comp;
 	int vq_id;
 };
@@ -267,6 +270,27 @@ static struct rproc_ops spacemit_rproc_ops = {
 	.get_boot_addr	= spacemit_get_boot_addr,
 };
 
+static int __process_theread(void *arg)
+{
+	int ret;
+	struct mbox_client *cl = arg;
+	struct rproc *rproc = dev_get_drvdata(cl->dev);
+	struct spacemit_mbox *mb = container_of(cl, struct spacemit_mbox, client);
+	struct sched_param param = {.sched_priority = 0 };
+
+	mb->kthread_running = true;
+	ret = sched_setscheduler(current, SCHED_FIFO, &param);
+
+	do {
+		wait_for_completion_timeout(&mb->mb_comp, 10);
+		if (rproc_vq_interrupt(rproc, mb->vq_id) == IRQ_NONE)
+			dev_dbg(&rproc->dev, "no message found in vq%d\n", mb->vq_id);
+	} while (!kthread_should_stop());
+
+	mb->kthread_running = false;
+
+	return 0;
+}
 static void k1x_rproc_mb_callback(struct mbox_client *cl, void *data)
 {
 	struct spacemit_mbox *mb = container_of(cl, struct spacemit_mbox, client);
@@ -281,9 +305,6 @@ static struct spacemit_mbox k1x_rpoc_mbox[] = {
 		.client = {
 			.rx_callback = k1x_rproc_mb_callback,
 			.tx_block = true,
-			.tx_done = NULL,
-			.tx_tout = 500,
-			.knows_txdone = false,
 		},
 	},
 	{
@@ -292,10 +313,7 @@ static struct spacemit_mbox k1x_rpoc_mbox[] = {
 		.client = {
 			.rx_callback = k1x_rproc_mb_callback,
 			.tx_block = true,
-			.tx_done = NULL,
-			.tx_tout = 500,
-			.knows_txdone = false,
-    },
+		},
 	},
 };
 
@@ -569,6 +587,12 @@ static int spacemit_rproc_probe(struct platform_device *pdev)
 			dev_err(dev, "failed to request mbox channel\n");
 			return -EINVAL;
 		}
+
+		if (priv->mb[i].vq_id >= 0) {
+			priv->mb[i].mb_thread = kthread_run(__process_theread, (void *)cl, name);
+			if (IS_ERR(priv->mb[i].mb_thread))
+				return PTR_ERR(priv->mb[i].mb_thread);
+		}
 	}
 
 #ifdef CONFIG_PM_SLEEP
@@ -604,7 +628,13 @@ static void k1x_rproc_free_mbox(struct rproc *rproc)
 
 static void spacemit_rproc_remove(struct platform_device *pdev)
 {
+	int i = 0;
 	struct rproc *rproc = platform_get_drvdata(pdev);
+	struct spacemit_rproc *ddata = rproc->priv;
+
+	for (i = 0; i < MAX_MBOX; ++i)
+		if (ddata->mb[i].kthread_running)
+			kthread_stop(ddata->mb[i].mb_thread);
 
 	rproc_del(rproc);
 	k1x_rproc_free_mbox(rproc);
@@ -625,11 +655,18 @@ MODULE_DEVICE_TABLE(of, spacemit_rproc_of_match);
 
 static void spacemit_rproc_shutdown(struct platform_device *pdev)
 {
+	int i;
 	struct rproc *rproc;
 	struct spacemit_rproc *priv;
 
 	rproc = dev_get_drvdata(&pdev->dev);
 	priv = rproc->priv;
+
+	for (i = 0; i < MAX_MBOX; ++i) {
+		/* release the resource of rt thread */
+		kthread_stop(priv->mb[i].mb_thread);
+		/* mbox_free_channel(priv->mb[i].chan); */
+	}
 }
 
 static struct platform_driver spacemit_rproc_driver = {
-- 
2.34.1