diff --git a/arch/arm/src/am67/am67_rptun.c b/arch/arm/src/am67/am67_rptun.c
index ce79df863e4..39ef0173191 100644
--- a/arch/arm/src/am67/am67_rptun.c
+++ b/arch/arm/src/am67/am67_rptun.c
@@ -93,6 +93,17 @@
 
 #define AM67_MBOX_USER          (3U)
 
+/* Control messages the Linux side exchanges in the mailbox payload.  Any
+ * value outside [READY, END_MSG) is a virtqueue index instead.  Values are
+ * from the TI kernel's drivers/remoteproc/omap_remoteproc.h; SHUTDOWN and
+ * SHUTDOWN_ACK are TI additions used by ti_k3_r5_remoteproc.c.
+ */
+
+#define RP_MBOX_READY           (0xffffff00ul)
+#define RP_MBOX_SHUTDOWN        (0xffffff14ul)
+#define RP_MBOX_SHUTDOWN_ACK    (0xffffff15ul)
+#define RP_MBOX_END_MSG         (0xffffff16ul)
+
 /* VIM IRQ number on MAIN_R5FSS0_0 for mailbox0_cluster3/user3 */
 
 #ifndef CONFIG_AM67_RPTUN_IRQ
@@ -141,7 +152,6 @@ static const struct rptun_addrenv_s *
 am67_rptun_get_addrenv(struct rptun_dev_s *dev);
 static struct resource_table *
 am67_rptun_get_resource(struct rptun_dev_s *dev);
-static size_t am67_rptun_get_rsc_size(struct rptun_dev_s *dev);
 static bool am67_rptun_is_autostart(struct rptun_dev_s *dev);
 static bool am67_rptun_is_master(struct rptun_dev_s *dev);
 static int am67_rptun_start(struct rptun_dev_s *dev);
@@ -161,7 +171,6 @@ static const struct rptun_ops_s g_am67_rptun_ops =
   .get_firmware      = am67_rptun_get_firmware,
   .get_addrenv       = am67_rptun_get_addrenv,
   .get_resource      = am67_rptun_get_resource,
-  .get_rsc_size      = am67_rptun_get_rsc_size,
   .is_autostart      = am67_rptun_is_autostart,
   .is_master         = am67_rptun_is_master,
   .start             = am67_rptun_start,
@@ -204,16 +213,6 @@ am67_rptun_get_resource(struct rptun_dev_s *dev)
   return (struct resource_table *)&g_am67_rsc_table;
 }
 
-static size_t am67_rptun_get_rsc_size(struct rptun_dev_s *dev)
-{
-  /* Return the real size of the extended resource table so that OpenAMP's
-   * remoteproc_set_rsc_table() can find both vdev entries (rptun.c would
-   * otherwise cap the visible region to sizeof(struct rptun_rsc_s)).
-   */
-
-  return sizeof(struct am67_rsc_s);
-}
-
 static bool am67_rptun_is_autostart(struct rptun_dev_s *dev)
 {
   return true; /* start rptun thread automatically */
@@ -309,14 +308,27 @@ static void am67_rptun_notify_work(void *arg)
 static int am67_rptun_interrupt(int irq, void *context, void *arg)
 {
   struct am67_rptun_dev_s *priv = (struct am67_rptun_dev_s *)arg;
+  bool shutdown = false;
+  bool kick = false;
 
   /* Drain all messages Linux wrote into FIFO 1.  Each read pops one
-   * entry; stop when MSG_STATUS reports 0 pending messages.
+   * entry; stop when MSG_STATUS reports 0 pending messages.  A single
+   * interrupt can carry both control messages and virtqueue kicks, so
+   * classify every entry rather than the batch.
    */
 
   while (getreg32(AM67_MBOX_MSG_STATUS(AM67_MBOX_RX_FIFO)) != 0)
     {
-      (void)getreg32(AM67_MBOX_MESSAGE(AM67_MBOX_RX_FIFO));
+      uint32_t msg = getreg32(AM67_MBOX_MESSAGE(AM67_MBOX_RX_FIFO));
+
+      if (msg == RP_MBOX_SHUTDOWN)
+        {
+          shutdown = true;
+        }
+      else if (msg < RP_MBOX_READY || msg >= RP_MBOX_END_MSG)
+        {
+          kick = true;
+        }
     }
 
   /* Clear the new-message interrupt status for user-3 / FIFO-1.
@@ -333,8 +345,26 @@ static int am67_rptun_interrupt(int irq, void *context, void *arg)
   putreg32(0, AM67_MBOX_EOI);
   UP_DSB();
 
+  /* Honour a shutdown request: acknowledge it, then park the core.  Linux
+   * polls the TI-SCI WFI status for 2 ms after the ACK and only halts the
+   * R5F once it sees us in WFI, so this must never return.
+   */
+
+  if (shutdown)
+    {
+      putreg32(RP_MBOX_SHUTDOWN_ACK, AM67_MBOX_MESSAGE(AM67_MBOX_TX_FIFO));
+      UP_DSB();
+
+      up_irq_save();
+
+      for (; ; )
+        {
+          __asm__ __volatile__ ("wfi");
+        }
+    }
+
   if (priv != NULL && priv->callback != NULL &&
-      work_available(&priv->work))
+      work_available(&priv->work) && kick)
     {
       work_queue(HPWORK, &priv->work, am67_rptun_notify_work, priv, 0);
     }