clk: scmi: register scmi clocks with CCF

Implements SCMI APIs to retrieve the number exposed SCMI clocks using
SCMI_PROTOCOL_ATTRIBUTES messages and the names of the clocks using
SCMI_CLOCK_ATTRIBUTES messages.

This change updates sandbox SCMI clock test driver to manage these
2 new message IDs.

Cc: Lukasz Majewski <lukma@denx.de>
Cc: Sean Anderson <seanga2@gmail.com>
Cc: Clement Leger <clement.leger@bootlin.com>
Cc: Patrick Delaunay <patrick.delaunay@foss.st.com>
Reviewed-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
Signed-off-by: Gabriel Fernandez <gabriel.fernandez@st.com>
Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org>

1 files changed, 90 insertions, 0 deletions

diff --git a/drivers/clk/clk_scmi.c b/drivers/clk/clk_scmi.c
index 42fbab0d21b..57022685e23 100644
--- a/drivers/clk/clk_scmi.c
+++ b/drivers/clk/clk_scmi.c
@@ -11,6 +11,52 @@
 #include <scmi_agent.h>
 #include <scmi_protocols.h>
 #include <asm/types.h>
+#include <linux/clk-provider.h>
+
+static int scmi_clk_get_num_clock(struct udevice *dev, size_t *num_clocks)
+{
+	struct scmi_clk_protocol_attr_out out;
+	struct scmi_msg msg = {
+		.protocol_id = SCMI_PROTOCOL_ID_CLOCK,
+		.message_id = SCMI_PROTOCOL_ATTRIBUTES,
+		.out_msg = (u8 *)&out,
+		.out_msg_sz = sizeof(out),
+	};
+	int ret;
+
+	ret = devm_scmi_process_msg(dev, &msg);
+	if (ret)
+		return ret;
+
+	*num_clocks = out.attributes & SCMI_CLK_PROTO_ATTR_COUNT_MASK;
+
+	return 0;
+}
+
+static int scmi_clk_get_attibute(struct udevice *dev, int clkid, char **name)
+{
+	struct scmi_clk_attribute_in in = {
+		.clock_id = clkid,
+	};
+	struct scmi_clk_attribute_out out;
+	struct scmi_msg msg = {
+		.protocol_id = SCMI_PROTOCOL_ID_CLOCK,
+		.message_id = SCMI_CLOCK_ATTRIBUTES,
+		.in_msg = (u8 *)&in,
+		.in_msg_sz = sizeof(in),
+		.out_msg = (u8 *)&out,
+		.out_msg_sz = sizeof(out),
+	};
+	int ret;
+
+	ret = devm_scmi_process_msg(dev, &msg);
+	if (ret)
+		return ret;
+
+	*name = out.clock_name;
+
+	return 0;
+}
 
 static int scmi_clk_gate(struct clk *clk, int enable)
 {
@@ -88,6 +134,49 @@ static ulong scmi_clk_set_rate(struct clk *clk, ulong rate)
 	return scmi_clk_get_rate(clk);
 }
 
+static int scmi_clk_probe(struct udevice *dev)
+{
+	struct clk *clk;
+	size_t num_clocks, i;
+	int ret;
+
+	if (!CONFIG_IS_ENABLED(CLK_CCF))
+		return 0;
+
+	/* register CCF children: CLK UCLASS, no probed again */
+	if (device_get_uclass_id(dev->parent) == UCLASS_CLK)
+		return 0;
+
+	ret = scmi_clk_get_num_clock(dev, &num_clocks);
+	if (ret)
+		return ret;
+
+	for (i = 0; i < num_clocks; i++) {
+		char *name;
+
+		if (!scmi_clk_get_attibute(dev, i, &name)) {
+			char *clock_name = strdup(name);
+
+			clk = kzalloc(sizeof(*clk), GFP_KERNEL);
+			if (!clk || !clock_name)
+				ret = -ENOMEM;
+			else
+				ret = clk_register(clk, dev->driver->name,
+						   clock_name, dev->name);
+
+			if (ret) {
+				free(clk);
+				free(clock_name);
+				return ret;
+			}
+
+			clk_dm(i, clk);
+		}
+	}
+
+	return 0;
+}
+
 static const struct clk_ops scmi_clk_ops = {
 	.enable = scmi_clk_enable,
 	.disable = scmi_clk_disable,
@@ -99,4 +188,5 @@ U_BOOT_DRIVER(scmi_clock) = {
 	.name = "scmi_clk",
 	.id = UCLASS_CLK,
 	.ops = &scmi_clk_ops,
+	.probe = &scmi_clk_probe,
 };