[PATCH v2 01/20] remoteproc: k3_system_controller: Support optional boot_notification channel

[Aswath Govindraju <a-govindraju@ti.com>]

From: Nishanth Menon <nm@ti.com>

If there is an optional boot notification channel that an SoC uses
separate from the rx path, use the same.

Signed-off-by: Nishanth Menon <nm@ti.com>
---
 .../remoteproc/k3-system-controller.txt       |  3 +++
 drivers/remoteproc/k3_system_controller.c     | 20 ++++++++++++++++++-
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/doc/device-tree-bindings/remoteproc/k3-system-controller.txt b/doc/device-tree-bindings/remoteproc/k3-system-controller.txt
index 32f4720b0d17..33dc46812ed4 100644
--- a/doc/device-tree-bindings/remoteproc/k3-system-controller.txt
+++ b/doc/device-tree-bindings/remoteproc/k3-system-controller.txt
@@ -13,6 +13,9 @@ Required properties:
 			"rx" for Receive channel
 - mboxes:		Corresponding phandles to mailbox channels.
 
+Optional properties:
+--------------------
+- mbox-names:		"boot_notify" for Optional alternate boot notification channel.
 
 Example:
 --------
diff --git a/drivers/remoteproc/k3_system_controller.c b/drivers/remoteproc/k3_system_controller.c
index 89cb90207dcb..e2affe69c678 100644
--- a/drivers/remoteproc/k3_system_controller.c
+++ b/drivers/remoteproc/k3_system_controller.c
@@ -77,14 +77,18 @@ struct k3_sysctrler_desc {
  * struct k3_sysctrler_privdata - Structure representing System Controller data.
  * @chan_tx:	Transmit mailbox channel
  * @chan_rx:	Receive mailbox channel
+ * @chan_boot_notify:	Boot notification channel
  * @desc:	SoC description for this instance
  * @seq_nr:	Counter for number of messages sent.
+ * @has_boot_notify:	Has separate boot notification channel
  */
 struct k3_sysctrler_privdata {
 	struct mbox_chan chan_tx;
 	struct mbox_chan chan_rx;
+	struct mbox_chan chan_boot_notify;
 	struct k3_sysctrler_desc *desc;
 	u32 seq_nr;
+	bool has_boot_notify;
 };
 
 static inline
@@ -223,7 +227,8 @@ static int k3_sysctrler_start(struct udevice *dev)
 	debug("%s(dev=%p)\n", __func__, dev);
 
 	/* Receive the boot notification. Note that it is sent only once. */
-	ret = mbox_recv(&priv->chan_rx, &msg, priv->desc->max_rx_timeout_us);
+	ret = mbox_recv(priv->has_boot_notify ? &priv->chan_boot_notify :
+			&priv->chan_rx, &msg, priv->desc->max_rx_timeout_us);
 	if (ret) {
 		dev_err(dev, "%s: Boot Notification response failed. ret = %d\n",
 			__func__, ret);
@@ -272,6 +277,19 @@ static int k3_of_to_priv(struct udevice *dev,
 		return ret;
 	}
 
+	/* Some SoCs may have a optional channel for boot notification. */
+	priv->has_boot_notify = 1;
+	ret = mbox_get_by_name(dev, "boot_notify", &priv->chan_boot_notify);
+	if (ret == -ENODATA) {
+		dev_dbg(dev, "%s: Acquiring optional Boot_notify failed. ret = %d. Using Rx\n",
+			__func__, ret);
+		priv->has_boot_notify = 0;
+	} else if (ret) {
+		dev_err(dev, "%s: Acquiring boot_notify channel failed. ret = %d\n",
+			__func__, ret);
+		return ret;
+	}
+
 	return 0;
 }
 
-- 
2.17.1