firmware: scmi: install base protocol to SCMI agent

SCMI base protocol is mandatory, and once SCMI node is found in a device
tree, the protocol handle (udevice) is unconditionally installed to
the agent. Then basic information will be retrieved from SCMI server via
the protocol and saved into the agent instance's local storage.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Etienne Carriere <etienne.carriere@foss.st.com>

1 files changed, 117 insertions, 1 deletions

diff --git a/drivers/firmware/scmi/scmi_agent-uclass.c b/drivers/firmware/scmi/scmi_agent-uclass.c
index b4d0088351..b1a9c36310 100644
--- a/drivers/firmware/scmi/scmi_agent-uclass.c
+++ b/drivers/firmware/scmi/scmi_agent-uclass.c
@@ -51,6 +51,9 @@ struct udevice *scmi_get_protocol(struct udevice *dev,
 	}
 
 	switch (id) {
+	case SCMI_PROTOCOL_ID_BASE:
+		proto = priv->base_dev;
+		break;
 	case SCMI_PROTOCOL_ID_CLOCK:
 		proto = priv->clock_dev;
 		break;
@@ -95,6 +98,9 @@ static int scmi_add_protocol(struct udevice *dev,
 	}
 
 	switch (proto_id) {
+	case SCMI_PROTOCOL_ID_BASE:
+		priv->base_dev = proto;
+		break;
 	case SCMI_PROTOCOL_ID_CLOCK:
 		priv->clock_dev = proto;
 		break;
@@ -232,6 +238,83 @@ int devm_scmi_process_msg(struct udevice *dev, struct scmi_msg *msg)
 	return scmi_process_msg(protocol->parent, priv->channel, msg);
 }
 
+/**
+ * scmi_fill_base_info - get base information about SCMI server
+ * @agent:	SCMI agent device
+ * @dev:	SCMI protocol device
+ *
+ * By using Base protocol commands, collect the base information
+ * about SCMI server.
+ *
+ * Return: 0 on success, error code on failure
+ */
+static int scmi_fill_base_info(struct udevice *agent, struct udevice *dev)
+{
+	struct scmi_agent_priv *priv = dev_get_uclass_plat(agent);
+	int ret;
+
+	ret = scmi_base_protocol_version(dev, &priv->version);
+	if (ret) {
+		dev_err(dev, "protocol_version() failed (%d)\n", ret);
+		return ret;
+	}
+	/* check for required version */
+	if (priv->version < SCMI_BASE_PROTOCOL_VERSION) {
+		dev_err(dev, "base protocol version (%d) lower than expected\n",
+			priv->version);
+		return -EPROTO;
+	}
+
+	ret = scmi_base_protocol_attrs(dev, &priv->num_agents,
+				       &priv->num_protocols);
+	if (ret) {
+		dev_err(dev, "protocol_attrs() failed (%d)\n", ret);
+		return ret;
+	}
+	ret = scmi_base_discover_vendor(dev, &priv->vendor);
+	if (ret) {
+		dev_err(dev, "base_discover_vendor() failed (%d)\n", ret);
+		return ret;
+	}
+	ret = scmi_base_discover_sub_vendor(dev, &priv->sub_vendor);
+	if (ret) {
+		if (ret != -EOPNOTSUPP) {
+			dev_err(dev, "base_discover_sub_vendor() failed (%d)\n",
+				ret);
+			return ret;
+		}
+		priv->sub_vendor = "NA";
+	}
+	ret = scmi_base_discover_impl_version(dev, &priv->impl_version);
+	if (ret) {
+		dev_err(dev, "base_discover_impl_version() failed (%d)\n",
+			ret);
+		return ret;
+	}
+
+	ret = scmi_base_discover_agent(dev, 0xffffffff,
+				       &priv->agent_id, &priv->agent_name);
+	if (ret) {
+		if (ret != -EOPNOTSUPP) {
+			dev_err(dev,
+				"base_discover_agent() failed for myself (%d)\n",
+				ret);
+			return ret;
+		}
+		priv->agent_id = 0xffffffff;
+		priv->agent_name = "NA";
+	}
+
+	ret = scmi_base_discover_list_protocols(dev, &priv->protocols);
+	if (ret != priv->num_protocols) {
+		dev_err(dev, "base_discover_list_protocols() failed (%d)\n",
+			ret);
+		return -EPROTO;
+	}
+
+	return 0;
+}
+
 /*
  * SCMI agent devices binds devices of various uclasses depending on
  * the FDT description. scmi_bind_protocol() is a generic bind sequence
@@ -243,7 +326,40 @@ static int scmi_bind_protocols(struct udevice *dev)
 	ofnode node;
 	const char *name;
 	struct driver *drv;
-	struct udevice *proto;
+	struct udevice *agent, *proto;
+
+	if (!uclass_get_device(UCLASS_SCMI_AGENT, 1, &agent)) {
+		/* This is a second SCMI agent */
+		dev_err(dev, "Cannot have more than one SCMI agent\n");
+		return -EEXIST;
+	}
+
+	/* initialize the device from device tree */
+	drv = DM_DRIVER_GET(scmi_base_drv);
+	name = "scmi-base.0";
+	ret = device_bind(dev, drv, name, NULL, ofnode_null(), &proto);
+	if (ret) {
+		dev_err(dev, "failed to bind base protocol\n");
+		return ret;
+	}
+	ret = scmi_add_protocol(dev, SCMI_PROTOCOL_ID_BASE, proto);
+	if (ret) {
+		dev_err(dev, "failed to add protocol: %s, ret: %d\n",
+			proto->name, ret);
+		return ret;
+	}
+
+	ret = device_probe(proto);
+	if (ret) {
+		dev_err(dev, "failed to probe base protocol\n");
+		return ret;
+	}
+
+	ret = scmi_fill_base_info(dev, proto);
+	if (ret) {
+		dev_err(dev, "failed to get base information\n");
+		return ret;
+	}
 
 	dev_for_each_subnode(node, dev) {
 		u32 protocol_id;