1 files changed, 99 insertions, 0 deletions
diff --git a/drivers/clk/clk_scmi.c b/drivers/clk/clk_scmi.c
new file mode 100644
index 0000000000..93a4819501
--- /dev/null
+++ b/drivers/clk/clk_scmi.c
@@ -0,0 +1,99 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2019-2020 Linaro Limited
+ */
+#include <common.h>
+#include <clk-uclass.h>
+#include <dm.h>
+#include <scmi_agent.h>
+#include <scmi_protocols.h>
+#include <asm/types.h>
+
+static int scmi_clk_gate(struct clk *clk, int enable)
+{
+	struct scmi_clk_state_in in = {
+		.clock_id = clk->id,
+		.attributes = enable,
+	};
+	struct scmi_clk_state_out out;
+	struct scmi_msg msg = SCMI_MSG_IN(SCMI_PROTOCOL_ID_CLOCK,
+					  SCMI_CLOCK_CONFIG_SET,
+					  in, out);
+	int ret;
+
+	ret = devm_scmi_process_msg(clk->dev->parent, &msg);
+	if (ret)
+		return ret;
+
+	return scmi_to_linux_errno(out.status);
+}
+
+static int scmi_clk_enable(struct clk *clk)
+{
+	return scmi_clk_gate(clk, 1);
+}
+
+static int scmi_clk_disable(struct clk *clk)
+{
+	return scmi_clk_gate(clk, 0);
+}
+
+static ulong scmi_clk_get_rate(struct clk *clk)
+{
+	struct scmi_clk_rate_get_in in = {
+		.clock_id = clk->id,
+	};
+	struct scmi_clk_rate_get_out out;
+	struct scmi_msg msg = SCMI_MSG_IN(SCMI_PROTOCOL_ID_CLOCK,
+					  SCMI_CLOCK_RATE_GET,
+					  in, out);
+	int ret;
+
+	ret = devm_scmi_process_msg(clk->dev->parent, &msg);
+	if (ret < 0)
+		return ret;
+
+	ret = scmi_to_linux_errno(out.status);
+	if (ret < 0)
+		return ret;
+
+	return (ulong)(((u64)out.rate_msb << 32) | out.rate_lsb);
+}
+
+static ulong scmi_clk_set_rate(struct clk *clk, ulong rate)
+{
+	struct scmi_clk_rate_set_in in = {
+		.clock_id = clk->id,
+		.flags = SCMI_CLK_RATE_ROUND_CLOSEST,
+		.rate_lsb = (u32)rate,
+		.rate_msb = (u32)((u64)rate >> 32),
+	};
+	struct scmi_clk_rate_set_out out;
+	struct scmi_msg msg = SCMI_MSG_IN(SCMI_PROTOCOL_ID_CLOCK,
+					  SCMI_CLOCK_RATE_SET,
+					  in, out);
+	int ret;
+
+	ret = devm_scmi_process_msg(clk->dev->parent, &msg);
+	if (ret < 0)
+		return ret;
+
+	ret = scmi_to_linux_errno(out.status);
+	if (ret < 0)
+		return ret;
+
+	return scmi_clk_get_rate(clk);
+}
+
+static const struct clk_ops scmi_clk_ops = {
+	.enable = scmi_clk_enable,
+	.disable = scmi_clk_disable,
+	.get_rate = scmi_clk_get_rate,
+	.set_rate = scmi_clk_set_rate,
+};
+
+U_BOOT_DRIVER(scmi_clock) = {
+	.name = "scmi_clk",
+	.id = UCLASS_CLK,
+	.ops = &scmi_clk_ops,
+};