1 files changed, 81 insertions, 0 deletions
diff --git a/drivers/reset/reset-scmi.c b/drivers/reset/reset-scmi.c
new file mode 100644
index 0000000000..1bff8075ee
--- /dev/null
+++ b/drivers/reset/reset-scmi.c
@@ -0,0 +1,81 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2019-2020 Linaro Limited
+ */
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <reset-uclass.h>
+#include <scmi_agent.h>
+#include <scmi_protocols.h>
+#include <asm/types.h>
+
+static int scmi_reset_set_level(struct reset_ctl *rst, bool assert_not_deassert)
+{
+	struct scmi_rd_reset_in in = {
+		.domain_id = rst->id,
+		.flags = assert_not_deassert ? SCMI_RD_RESET_FLAG_ASSERT : 0,
+		.reset_state = 0,
+	};
+	struct scmi_rd_reset_out out;
+	struct scmi_msg msg = SCMI_MSG_IN(SCMI_PROTOCOL_ID_RESET_DOMAIN,
+					  SCMI_RESET_DOMAIN_RESET,
+					  in, out);
+	int ret;
+
+	ret = devm_scmi_process_msg(rst->dev->parent, &msg);
+	if (ret)
+		return ret;
+
+	return scmi_to_linux_errno(out.status);
+}
+
+static int scmi_reset_assert(struct reset_ctl *rst)
+{
+	return scmi_reset_set_level(rst, true);
+}
+
+static int scmi_reset_deassert(struct reset_ctl *rst)
+{
+	return scmi_reset_set_level(rst, false);
+}
+
+static int scmi_reset_request(struct reset_ctl *rst)
+{
+	struct scmi_rd_attr_in in = {
+		.domain_id = rst->id,
+	};
+	struct scmi_rd_attr_out out;
+	struct scmi_msg msg = SCMI_MSG_IN(SCMI_PROTOCOL_ID_RESET_DOMAIN,
+					  SCMI_RESET_DOMAIN_ATTRIBUTES,
+					  in, out);
+	int ret;
+
+	/*
+	 * We don't really care about the attribute, just check
+	 * the reset domain exists.
+	 */
+	ret = devm_scmi_process_msg(rst->dev->parent, &msg);
+	if (ret)
+		return ret;
+
+	return scmi_to_linux_errno(out.status);
+}
+
+static int scmi_reset_rfree(struct reset_ctl *rst)
+{
+	return 0;
+}
+
+static const struct reset_ops scmi_reset_domain_ops = {
+	.request	= scmi_reset_request,
+	.rfree		= scmi_reset_rfree,
+	.rst_assert	= scmi_reset_assert,
+	.rst_deassert	= scmi_reset_deassert,
+};
+
+U_BOOT_DRIVER(scmi_reset_domain) = {
+	.name = "scmi_reset_domain",
+	.id = UCLASS_RESET,
+	.ops = &scmi_reset_domain_ops,
+};