firmware: ti_sci: Add support for reboot core service

Since system controller now has control over SoC power management, it
needs to be explicitly requested to reboot the SoC. Add support for
it.

Reviewed-by: Tom Rini <trini@konsulko.com>
Signed-off-by: Andreas Dannenberg <dannenberg@ti.com>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Nishanth Menon <nm@ti.com>

drivers/firmware/ti_sci.c

@@ -1397,6 +1397,50 @@ static int ti_sci_cmd_clk_get_freq(const struct ti_sci_handle *handle,
 	return ret;
 }
 
+/**
+ * ti_sci_cmd_core_reboot() - Command to request system reset
+ * @handle:	pointer to TI SCI handle
+ *
+ * Return: 0 if all went well, else returns appropriate error value.
+ */
+static int ti_sci_cmd_core_reboot(const struct ti_sci_handle *handle)
+{
+	struct ti_sci_msg_req_reboot req;
+	struct ti_sci_msg_hdr *resp;
+	struct ti_sci_info *info;
+	struct ti_sci_xfer *xfer;
+	int ret = 0;
+
+	if (IS_ERR(handle))
+		return PTR_ERR(handle);
+	if (!handle)
+		return -EINVAL;
+
+	info = handle_to_ti_sci_info(handle);
+
+	xfer = ti_sci_setup_one_xfer(info, TI_SCI_MSG_SYS_RESET,
+				     TI_SCI_FLAG_REQ_ACK_ON_PROCESSED,
+				     (u32 *)&req, sizeof(req), sizeof(*resp));
+	if (IS_ERR(xfer)) {
+		ret = PTR_ERR(xfer);
+		dev_err(info->dev, "Message alloc failed(%d)\n", ret);
+		return ret;
+	}
+
+	ret = ti_sci_do_xfer(info, xfer);
+	if (ret) {
+		dev_err(dev, "Mbox send fail %d\n", ret);
+		return ret;
+	}
+
+	resp = (struct ti_sci_msg_hdr *)xfer->tx_message.buf;
+
+	if (!ti_sci_is_response_ack(resp))
+		return -ENODEV;
+
+	return ret;
+}
+
 /*
  * ti_sci_setup_ops() - Setup the operations structures
  * @info:	pointer to TISCI pointer
@@ -1407,6 +1451,7 @@ static void ti_sci_setup_ops(struct ti_sci_info *info)
 	struct ti_sci_board_ops *bops = &ops->board_ops;
 	struct ti_sci_dev_ops *dops = &ops->dev_ops;
 	struct ti_sci_clk_ops *cops = &ops->clk_ops;
+	struct ti_sci_core_ops *core_ops = &ops->core_ops;
 
 	bops->board_config = ti_sci_cmd_set_board_config;
 	bops->board_config_rm = ti_sci_cmd_set_board_config_rm;
@@ -1439,6 +1484,8 @@ static void ti_sci_setup_ops(struct ti_sci_info *info)
 	cops->get_best_match_freq = ti_sci_cmd_clk_get_match_freq;
 	cops->set_freq = ti_sci_cmd_clk_set_freq;
 	cops->get_freq = ti_sci_cmd_clk_get_freq;
+
+	core_ops->reboot_device = ti_sci_cmd_core_reboot;
 }
 
 /**

drivers/firmware/ti_sci.h

@@ -96,6 +96,17 @@ struct ti_sci_msg_resp_version {
 } __packed;
 
 /**
+ * struct ti_sci_msg_req_reboot - Reboot the SoC
+ * @hdr:	Generic Header
+ *
+ * Request type is TI_SCI_MSG_SYS_RESET, responded with a generic
+ * ACK/NACK message.
+ */
+struct ti_sci_msg_req_reboot {
+	struct ti_sci_msg_hdr hdr;
+} __packed;
+
+/**
  * struct ti_sci_msg_board_config - Board configuration message
  * @hdr:		Generic Header
  * @boardcfgp_low:	Lower 32 bit of the pointer pointing to the board

include/linux/soc/ti/ti_sci_protocol.h

@@ -213,15 +213,27 @@ struct ti_sci_clk_ops {
 };
 
 /**
+ * struct ti_sci_core_ops - SoC Core Operations
+ * @reboot_device: Reboot the SoC
+ *		Returns 0 for successful request(ideally should never return),
+ *		else returns corresponding error value.
+ */
+struct ti_sci_core_ops {
+	int (*reboot_device)(const struct ti_sci_handle *handle);
+};
+
+/**
  * struct ti_sci_ops - Function support for TI SCI
  * @board_ops:	Miscellaneous operations
  * @dev_ops:	Device specific operations
  * @clk_ops:	Clock specific operations
+ * @core_ops:	Core specific operations
  */
 struct ti_sci_ops {
 	struct ti_sci_board_ops board_ops;
 	struct ti_sci_dev_ops dev_ops;
 	struct ti_sci_clk_ops clk_ops;
+	struct ti_sci_core_ops core_ops;
 };
 
 /**