1 files changed, 356 insertions, 0 deletions
diff --git a/drivers/firmware/arm_scmi/reset.c b/drivers/firmware/arm_scmi/reset.c
new file mode 100644
index 000000000..e9afa8cab
--- /dev/null
+++ b/drivers/firmware/arm_scmi/reset.c
@@ -0,0 +1,356 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * System Control and Management Interface (SCMI) Reset Protocol
+ *
+ * Copyright (C) 2019-2022 ARM Ltd.
+ */
+
+#define pr_fmt(fmt) "SCMI Notifications RESET - " fmt
+
+#include <linux/module.h>
+#include <linux/scmi_protocol.h>
+
+#include "protocols.h"
+#include "notify.h"
+
+enum scmi_reset_protocol_cmd {
+	RESET_DOMAIN_ATTRIBUTES = 0x3,
+	RESET = 0x4,
+	RESET_NOTIFY = 0x5,
+	RESET_DOMAIN_NAME_GET = 0x6,
+};
+
+#define NUM_RESET_DOMAIN_MASK	0xffff
+#define RESET_NOTIFY_ENABLE	BIT(0)
+
+struct scmi_msg_resp_reset_domain_attributes {
+	__le32 attributes;
+#define SUPPORTS_ASYNC_RESET(x)		((x) & BIT(31))
+#define SUPPORTS_NOTIFY_RESET(x)	((x) & BIT(30))
+#define SUPPORTS_EXTENDED_NAMES(x)	((x) & BIT(29))
+	__le32 latency;
+	u8 name[SCMI_SHORT_NAME_MAX_SIZE];
+};
+
+struct scmi_msg_reset_domain_reset {
+	__le32 domain_id;
+	__le32 flags;
+#define AUTONOMOUS_RESET	BIT(0)
+#define EXPLICIT_RESET_ASSERT	BIT(1)
+#define ASYNCHRONOUS_RESET	BIT(2)
+	__le32 reset_state;
+#define ARCH_COLD_RESET		0
+};
+
+struct scmi_msg_reset_notify {
+	__le32 id;
+	__le32 event_control;
+#define RESET_TP_NOTIFY_ALL	BIT(0)
+};
+
+struct scmi_reset_issued_notify_payld {
+	__le32 agent_id;
+	__le32 domain_id;
+	__le32 reset_state;
+};
+
+struct reset_dom_info {
+	bool async_reset;
+	bool reset_notify;
+	u32 latency_us;
+	char name[SCMI_MAX_STR_SIZE];
+};
+
+struct scmi_reset_info {
+	u32 version;
+	int num_domains;
+	struct reset_dom_info *dom_info;
+};
+
+static int scmi_reset_attributes_get(const struct scmi_protocol_handle *ph,
+				     struct scmi_reset_info *pi)
+{
+	int ret;
+	struct scmi_xfer *t;
+	u32 attr;
+
+	ret = ph->xops->xfer_get_init(ph, PROTOCOL_ATTRIBUTES,
+				      0, sizeof(attr), &t);
+	if (ret)
+		return ret;
+
+	ret = ph->xops->do_xfer(ph, t);
+	if (!ret) {
+		attr = get_unaligned_le32(t->rx.buf);
+		pi->num_domains = attr & NUM_RESET_DOMAIN_MASK;
+	}
+
+	ph->xops->xfer_put(ph, t);
+	return ret;
+}
+
+static int
+scmi_reset_domain_attributes_get(const struct scmi_protocol_handle *ph,
+				 u32 domain, struct reset_dom_info *dom_info,
+				 u32 version)
+{
+	int ret;
+	u32 attributes;
+	struct scmi_xfer *t;
+	struct scmi_msg_resp_reset_domain_attributes *attr;
+
+	ret = ph->xops->xfer_get_init(ph, RESET_DOMAIN_ATTRIBUTES,
+				      sizeof(domain), sizeof(*attr), &t);
+	if (ret)
+		return ret;
+
+	put_unaligned_le32(domain, t->tx.buf);
+	attr = t->rx.buf;
+
+	ret = ph->xops->do_xfer(ph, t);
+	if (!ret) {
+		attributes = le32_to_cpu(attr->attributes);
+
+		dom_info->async_reset = SUPPORTS_ASYNC_RESET(attributes);
+		dom_info->reset_notify = SUPPORTS_NOTIFY_RESET(attributes);
+		dom_info->latency_us = le32_to_cpu(attr->latency);
+		if (dom_info->latency_us == U32_MAX)
+			dom_info->latency_us = 0;
+		strscpy(dom_info->name, attr->name, SCMI_SHORT_NAME_MAX_SIZE);
+	}
+
+	ph->xops->xfer_put(ph, t);
+
+	/*
+	 * If supported overwrite short name with the extended one;
+	 * on error just carry on and use already provided short name.
+	 */
+	if (!ret && PROTOCOL_REV_MAJOR(version) >= 0x3 &&
+	    SUPPORTS_EXTENDED_NAMES(attributes))
+		ph->hops->extended_name_get(ph, RESET_DOMAIN_NAME_GET, domain,
+					    dom_info->name, SCMI_MAX_STR_SIZE);
+
+	return ret;
+}
+
+static int scmi_reset_num_domains_get(const struct scmi_protocol_handle *ph)
+{
+	struct scmi_reset_info *pi = ph->get_priv(ph);
+
+	return pi->num_domains;
+}
+
+static const char *
+scmi_reset_name_get(const struct scmi_protocol_handle *ph, u32 domain)
+{
+	struct scmi_reset_info *pi = ph->get_priv(ph);
+
+	struct reset_dom_info *dom = pi->dom_info + domain;
+
+	return dom->name;
+}
+
+static int scmi_reset_latency_get(const struct scmi_protocol_handle *ph,
+				  u32 domain)
+{
+	struct scmi_reset_info *pi = ph->get_priv(ph);
+	struct reset_dom_info *dom = pi->dom_info + domain;
+
+	return dom->latency_us;
+}
+
+static int scmi_domain_reset(const struct scmi_protocol_handle *ph, u32 domain,
+			     u32 flags, u32 state)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_msg_reset_domain_reset *dom;
+	struct scmi_reset_info *pi = ph->get_priv(ph);
+	struct reset_dom_info *rdom;
+
+	if (domain >= pi->num_domains)
+		return -EINVAL;
+
+	rdom = pi->dom_info + domain;
+	if (rdom->async_reset && flags & AUTONOMOUS_RESET)
+		flags |= ASYNCHRONOUS_RESET;
+
+	ret = ph->xops->xfer_get_init(ph, RESET, sizeof(*dom), 0, &t);
+	if (ret)
+		return ret;
+
+	dom = t->tx.buf;
+	dom->domain_id = cpu_to_le32(domain);
+	dom->flags = cpu_to_le32(flags);
+	dom->reset_state = cpu_to_le32(state);
+
+	if (flags & ASYNCHRONOUS_RESET)
+		ret = ph->xops->do_xfer_with_response(ph, t);
+	else
+		ret = ph->xops->do_xfer(ph, t);
+
+	ph->xops->xfer_put(ph, t);
+	return ret;
+}
+
+static int scmi_reset_domain_reset(const struct scmi_protocol_handle *ph,
+				   u32 domain)
+{
+	return scmi_domain_reset(ph, domain, AUTONOMOUS_RESET,
+				 ARCH_COLD_RESET);
+}
+
+static int
+scmi_reset_domain_assert(const struct scmi_protocol_handle *ph, u32 domain)
+{
+	return scmi_domain_reset(ph, domain, EXPLICIT_RESET_ASSERT,
+				 ARCH_COLD_RESET);
+}
+
+static int
+scmi_reset_domain_deassert(const struct scmi_protocol_handle *ph, u32 domain)
+{
+	return scmi_domain_reset(ph, domain, 0, ARCH_COLD_RESET);
+}
+
+static const struct scmi_reset_proto_ops reset_proto_ops = {
+	.num_domains_get = scmi_reset_num_domains_get,
+	.name_get = scmi_reset_name_get,
+	.latency_get = scmi_reset_latency_get,
+	.reset = scmi_reset_domain_reset,
+	.assert = scmi_reset_domain_assert,
+	.deassert = scmi_reset_domain_deassert,
+};
+
+static int scmi_reset_notify(const struct scmi_protocol_handle *ph,
+			     u32 domain_id, bool enable)
+{
+	int ret;
+	u32 evt_cntl = enable ? RESET_TP_NOTIFY_ALL : 0;
+	struct scmi_xfer *t;
+	struct scmi_msg_reset_notify *cfg;
+
+	ret = ph->xops->xfer_get_init(ph, RESET_NOTIFY, sizeof(*cfg), 0, &t);
+	if (ret)
+		return ret;
+
+	cfg = t->tx.buf;
+	cfg->id = cpu_to_le32(domain_id);
+	cfg->event_control = cpu_to_le32(evt_cntl);
+
+	ret = ph->xops->do_xfer(ph, t);
+
+	ph->xops->xfer_put(ph, t);
+	return ret;
+}
+
+static int scmi_reset_set_notify_enabled(const struct scmi_protocol_handle *ph,
+					 u8 evt_id, u32 src_id, bool enable)
+{
+	int ret;
+
+	ret = scmi_reset_notify(ph, src_id, enable);
+	if (ret)
+		pr_debug("FAIL_ENABLED - evt[%X] dom[%d] - ret:%d\n",
+			 evt_id, src_id, ret);
+
+	return ret;
+}
+
+static void *
+scmi_reset_fill_custom_report(const struct scmi_protocol_handle *ph,
+			      u8 evt_id, ktime_t timestamp,
+			      const void *payld, size_t payld_sz,
+			      void *report, u32 *src_id)
+{
+	const struct scmi_reset_issued_notify_payld *p = payld;
+	struct scmi_reset_issued_report *r = report;
+
+	if (evt_id != SCMI_EVENT_RESET_ISSUED || sizeof(*p) != payld_sz)
+		return NULL;
+
+	r->timestamp = timestamp;
+	r->agent_id = le32_to_cpu(p->agent_id);
+	r->domain_id = le32_to_cpu(p->domain_id);
+	r->reset_state = le32_to_cpu(p->reset_state);
+	*src_id = r->domain_id;
+
+	return r;
+}
+
+static int scmi_reset_get_num_sources(const struct scmi_protocol_handle *ph)
+{
+	struct scmi_reset_info *pinfo = ph->get_priv(ph);
+
+	if (!pinfo)
+		return -EINVAL;
+
+	return pinfo->num_domains;
+}
+
+static const struct scmi_event reset_events[] = {
+	{
+		.id = SCMI_EVENT_RESET_ISSUED,
+		.max_payld_sz = sizeof(struct scmi_reset_issued_notify_payld),
+		.max_report_sz = sizeof(struct scmi_reset_issued_report),
+	},
+};
+
+static const struct scmi_event_ops reset_event_ops = {
+	.get_num_sources = scmi_reset_get_num_sources,
+	.set_notify_enabled = scmi_reset_set_notify_enabled,
+	.fill_custom_report = scmi_reset_fill_custom_report,
+};
+
+static const struct scmi_protocol_events reset_protocol_events = {
+	.queue_sz = SCMI_PROTO_QUEUE_SZ,
+	.ops = &reset_event_ops,
+	.evts = reset_events,
+	.num_events = ARRAY_SIZE(reset_events),
+};
+
+static int scmi_reset_protocol_init(const struct scmi_protocol_handle *ph)
+{
+	int domain, ret;
+	u32 version;
+	struct scmi_reset_info *pinfo;
+
+	ret = ph->xops->version_get(ph, &version);
+	if (ret)
+		return ret;
+
+	dev_dbg(ph->dev, "Reset Version %d.%d\n",
+		PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
+
+	pinfo = devm_kzalloc(ph->dev, sizeof(*pinfo), GFP_KERNEL);
+	if (!pinfo)
+		return -ENOMEM;
+
+	ret = scmi_reset_attributes_get(ph, pinfo);
+	if (ret)
+		return ret;
+
+	pinfo->dom_info = devm_kcalloc(ph->dev, pinfo->num_domains,
+				       sizeof(*pinfo->dom_info), GFP_KERNEL);
+	if (!pinfo->dom_info)
+		return -ENOMEM;
+
+	for (domain = 0; domain < pinfo->num_domains; domain++) {
+		struct reset_dom_info *dom = pinfo->dom_info + domain;
+
+		scmi_reset_domain_attributes_get(ph, domain, dom, version);
+	}
+
+	pinfo->version = version;
+	return ph->set_priv(ph, pinfo);
+}
+
+static const struct scmi_protocol scmi_reset = {
+	.id = SCMI_PROTOCOL_RESET,
+	.owner = THIS_MODULE,
+	.instance_init = &scmi_reset_protocol_init,
+	.ops = &reset_proto_ops,
+	.events = &reset_protocol_events,
+};
+
+DEFINE_SCMI_PROTOCOL_REGISTER_UNREGISTER(reset, scmi_reset)