firmware: arm_scmi: Add internal platform/channel identifiers

Add a couple of unique identifiers to channel and platform instance
descriptors in order to emit more descriptive message dump traces.
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lore.kernel.org/r/20230118121426.492864-8-cristian.marussi@arm.comSigned-off-by: Sudeep Holla <sudeep.holla@arm.com>

drivers/firmware/arm_scmi/common.h

@@ -157,6 +157,8 @@ void scmi_protocol_release(const struct scmi_handle *handle, u8 protocol_id);
 /**
  * struct scmi_chan_info - Structure representing a SCMI channel information
  *
+ * @id: An identifier for this channel: this matches the protocol number
+ *      used to initialize this channel
  * @dev: Reference to device in the SCMI hierarchy corresponding to this
  *	 channel
  * @rx_timeout_ms: The configured RX timeout in milliseconds.
@@ -168,6 +170,7 @@ void scmi_protocol_release(const struct scmi_handle *handle, u8 protocol_id);
  * @transport_info: Transport layer related information
  */
 struct scmi_chan_info {
+	int id;
 	struct device *dev;
 	unsigned int rx_timeout_ms;
 	struct scmi_handle *handle;

drivers/firmware/arm_scmi/driver.c

@@ -39,6 +39,8 @@
 #define CREATE_TRACE_POINTS
 #include <trace/events/scmi.h>
 
+static DEFINE_IDA(scmi_id);
+
 static DEFINE_IDR(scmi_protocols);
 static DEFINE_SPINLOCK(protocol_lock);
 
@@ -98,6 +100,7 @@ struct scmi_protocol_instance {
 /**
  * struct scmi_info - Structure representing a SCMI instance
  *
+ * @id: A sequence number starting from zero identifying this instance
  * @dev: Device pointer
  * @desc: SoC description for this instance
  * @version: SCMI revision information containing protocol version,
@@ -131,6 +134,7 @@ struct scmi_protocol_instance {
  * @devreq_mtx: A mutex to serialize device creation for this SCMI instance
  */
 struct scmi_info {
+	int id;
 	struct device *dev;
 	const struct scmi_desc *desc;
 	struct scmi_revision_info version;
@@ -2270,6 +2274,7 @@ static int scmi_chan_setup(struct scmi_info *info, struct device_node *of_node,
 	}
 	of_node_get(of_node);
 
+	cinfo->id = prot_id;
 	cinfo->dev = &tdev->dev;
 	ret = info->desc->ops->chan_setup(cinfo, info->dev, tx);
 	if (ret) {
@@ -2486,6 +2491,10 @@ static int scmi_probe(struct platform_device *pdev)
 	if (!info)
 		return -ENOMEM;
 
+	info->id = ida_alloc_min(&scmi_id, 0, GFP_KERNEL);
+	if (info->id < 0)
+		return info->id;
+
 	info->dev = dev;
 	info->desc = desc;
 	info->bus_nb.notifier_call = scmi_bus_notifier;
@@ -2518,13 +2527,13 @@ static int scmi_probe(struct platform_device *pdev)
 	if (desc->ops->link_supplier) {
 		ret = desc->ops->link_supplier(dev);
 		if (ret)
-			return ret;
+			goto clear_ida;
 	}
 
 	/* Setup all channels described in the DT at first */
 	ret = scmi_channels_setup(info);
 	if (ret)
-		return ret;
+		goto clear_ida;
 
 	ret = bus_register_notifier(&scmi_bus_type, &info->bus_nb);
 	if (ret)
@@ -2604,6 +2613,8 @@ static int scmi_probe(struct platform_device *pdev)
 	bus_unregister_notifier(&scmi_bus_type, &info->bus_nb);
 clear_txrx_setup:
 	scmi_cleanup_txrx_channels(info);
+clear_ida:
+	ida_free(&scmi_id, info->id);
 	return ret;
 }
 
@@ -2637,6 +2648,8 @@ static int scmi_remove(struct platform_device *pdev)
 	/* Safe to free channels since no more users */
 	scmi_cleanup_txrx_channels(info);
 
+	ida_free(&scmi_id, info->id);
+
 	return 0;
 }