1 files changed, 342 insertions, 0 deletions
diff --git a/drivers/firmware/arm_scmi/power.c b/drivers/firmware/arm_scmi/power.c
new file mode 100644
index 000000000..356e83631
--- /dev/null
+++ b/drivers/firmware/arm_scmi/power.c
@@ -0,0 +1,342 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * System Control and Management Interface (SCMI) Power Protocol
+ *
+ * Copyright (C) 2018-2022 ARM Ltd.
+ */
+
+#define pr_fmt(fmt) "SCMI Notifications POWER - " fmt
+
+#include <linux/module.h>
+#include <linux/scmi_protocol.h>
+
+#include "protocols.h"
+#include "notify.h"
+
+enum scmi_power_protocol_cmd {
+	POWER_DOMAIN_ATTRIBUTES = 0x3,
+	POWER_STATE_SET = 0x4,
+	POWER_STATE_GET = 0x5,
+	POWER_STATE_NOTIFY = 0x6,
+	POWER_DOMAIN_NAME_GET = 0x8,
+};
+
+struct scmi_msg_resp_power_attributes {
+	__le16 num_domains;
+	__le16 reserved;
+	__le32 stats_addr_low;
+	__le32 stats_addr_high;
+	__le32 stats_size;
+};
+
+struct scmi_msg_resp_power_domain_attributes {
+	__le32 flags;
+#define SUPPORTS_STATE_SET_NOTIFY(x)	((x) & BIT(31))
+#define SUPPORTS_STATE_SET_ASYNC(x)	((x) & BIT(30))
+#define SUPPORTS_STATE_SET_SYNC(x)	((x) & BIT(29))
+#define SUPPORTS_EXTENDED_NAMES(x)	((x) & BIT(27))
+	    u8 name[SCMI_SHORT_NAME_MAX_SIZE];
+};
+
+struct scmi_power_set_state {
+	__le32 flags;
+#define STATE_SET_ASYNC		BIT(0)
+	__le32 domain;
+	__le32 state;
+};
+
+struct scmi_power_state_notify {
+	__le32 domain;
+	__le32 notify_enable;
+};
+
+struct scmi_power_state_notify_payld {
+	__le32 agent_id;
+	__le32 domain_id;
+	__le32 power_state;
+};
+
+struct power_dom_info {
+	bool state_set_sync;
+	bool state_set_async;
+	bool state_set_notify;
+	char name[SCMI_MAX_STR_SIZE];
+};
+
+struct scmi_power_info {
+	u32 version;
+	int num_domains;
+	u64 stats_addr;
+	u32 stats_size;
+	struct power_dom_info *dom_info;
+};
+
+static int scmi_power_attributes_get(const struct scmi_protocol_handle *ph,
+				     struct scmi_power_info *pi)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_msg_resp_power_attributes *attr;
+
+	ret = ph->xops->xfer_get_init(ph, PROTOCOL_ATTRIBUTES,
+				      0, sizeof(*attr), &t);
+	if (ret)
+		return ret;
+
+	attr = t->rx.buf;
+
+	ret = ph->xops->do_xfer(ph, t);
+	if (!ret) {
+		pi->num_domains = le16_to_cpu(attr->num_domains);
+		pi->stats_addr = le32_to_cpu(attr->stats_addr_low) |
+				(u64)le32_to_cpu(attr->stats_addr_high) << 32;
+		pi->stats_size = le32_to_cpu(attr->stats_size);
+	}
+
+	ph->xops->xfer_put(ph, t);
+	return ret;
+}
+
+static int
+scmi_power_domain_attributes_get(const struct scmi_protocol_handle *ph,
+				 u32 domain, struct power_dom_info *dom_info,
+				 u32 version)
+{
+	int ret;
+	u32 flags;
+	struct scmi_xfer *t;
+	struct scmi_msg_resp_power_domain_attributes *attr;
+
+	ret = ph->xops->xfer_get_init(ph, POWER_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) {
+		flags = le32_to_cpu(attr->flags);
+
+		dom_info->state_set_notify = SUPPORTS_STATE_SET_NOTIFY(flags);
+		dom_info->state_set_async = SUPPORTS_STATE_SET_ASYNC(flags);
+		dom_info->state_set_sync = SUPPORTS_STATE_SET_SYNC(flags);
+		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(flags)) {
+		ph->hops->extended_name_get(ph, POWER_DOMAIN_NAME_GET,
+					    domain, dom_info->name,
+					    SCMI_MAX_STR_SIZE);
+	}
+
+	return ret;
+}
+
+static int scmi_power_state_set(const struct scmi_protocol_handle *ph,
+				u32 domain, u32 state)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_power_set_state *st;
+
+	ret = ph->xops->xfer_get_init(ph, POWER_STATE_SET, sizeof(*st), 0, &t);
+	if (ret)
+		return ret;
+
+	st = t->tx.buf;
+	st->flags = cpu_to_le32(0);
+	st->domain = cpu_to_le32(domain);
+	st->state = cpu_to_le32(state);
+
+	ret = ph->xops->do_xfer(ph, t);
+
+	ph->xops->xfer_put(ph, t);
+	return ret;
+}
+
+static int scmi_power_state_get(const struct scmi_protocol_handle *ph,
+				u32 domain, u32 *state)
+{
+	int ret;
+	struct scmi_xfer *t;
+
+	ret = ph->xops->xfer_get_init(ph, POWER_STATE_GET, sizeof(u32), sizeof(u32), &t);
+	if (ret)
+		return ret;
+
+	put_unaligned_le32(domain, t->tx.buf);
+
+	ret = ph->xops->do_xfer(ph, t);
+	if (!ret)
+		*state = get_unaligned_le32(t->rx.buf);
+
+	ph->xops->xfer_put(ph, t);
+	return ret;
+}
+
+static int scmi_power_num_domains_get(const struct scmi_protocol_handle *ph)
+{
+	struct scmi_power_info *pi = ph->get_priv(ph);
+
+	return pi->num_domains;
+}
+
+static const char *
+scmi_power_name_get(const struct scmi_protocol_handle *ph,
+		    u32 domain)
+{
+	struct scmi_power_info *pi = ph->get_priv(ph);
+	struct power_dom_info *dom = pi->dom_info + domain;
+
+	return dom->name;
+}
+
+static const struct scmi_power_proto_ops power_proto_ops = {
+	.num_domains_get = scmi_power_num_domains_get,
+	.name_get = scmi_power_name_get,
+	.state_set = scmi_power_state_set,
+	.state_get = scmi_power_state_get,
+};
+
+static int scmi_power_request_notify(const struct scmi_protocol_handle *ph,
+				     u32 domain, bool enable)
+{
+	int ret;
+	struct scmi_xfer *t;
+	struct scmi_power_state_notify *notify;
+
+	ret = ph->xops->xfer_get_init(ph, POWER_STATE_NOTIFY,
+				      sizeof(*notify), 0, &t);
+	if (ret)
+		return ret;
+
+	notify = t->tx.buf;
+	notify->domain = cpu_to_le32(domain);
+	notify->notify_enable = enable ? cpu_to_le32(BIT(0)) : 0;
+
+	ret = ph->xops->do_xfer(ph, t);
+
+	ph->xops->xfer_put(ph, t);
+	return ret;
+}
+
+static int scmi_power_set_notify_enabled(const struct scmi_protocol_handle *ph,
+					 u8 evt_id, u32 src_id, bool enable)
+{
+	int ret;
+
+	ret = scmi_power_request_notify(ph, src_id, enable);
+	if (ret)
+		pr_debug("FAIL_ENABLE - evt[%X] dom[%d] - ret:%d\n",
+			 evt_id, src_id, ret);
+
+	return ret;
+}
+
+static void *
+scmi_power_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_power_state_notify_payld *p = payld;
+	struct scmi_power_state_changed_report *r = report;
+
+	if (evt_id != SCMI_EVENT_POWER_STATE_CHANGED || 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->power_state = le32_to_cpu(p->power_state);
+	*src_id = r->domain_id;
+
+	return r;
+}
+
+static int scmi_power_get_num_sources(const struct scmi_protocol_handle *ph)
+{
+	struct scmi_power_info *pinfo = ph->get_priv(ph);
+
+	if (!pinfo)
+		return -EINVAL;
+
+	return pinfo->num_domains;
+}
+
+static const struct scmi_event power_events[] = {
+	{
+		.id = SCMI_EVENT_POWER_STATE_CHANGED,
+		.max_payld_sz = sizeof(struct scmi_power_state_notify_payld),
+		.max_report_sz =
+			sizeof(struct scmi_power_state_changed_report),
+	},
+};
+
+static const struct scmi_event_ops power_event_ops = {
+	.get_num_sources = scmi_power_get_num_sources,
+	.set_notify_enabled = scmi_power_set_notify_enabled,
+	.fill_custom_report = scmi_power_fill_custom_report,
+};
+
+static const struct scmi_protocol_events power_protocol_events = {
+	.queue_sz = SCMI_PROTO_QUEUE_SZ,
+	.ops = &power_event_ops,
+	.evts = power_events,
+	.num_events = ARRAY_SIZE(power_events),
+};
+
+static int scmi_power_protocol_init(const struct scmi_protocol_handle *ph)
+{
+	int domain, ret;
+	u32 version;
+	struct scmi_power_info *pinfo;
+
+	ret = ph->xops->version_get(ph, &version);
+	if (ret)
+		return ret;
+
+	dev_dbg(ph->dev, "Power 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_power_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 power_dom_info *dom = pinfo->dom_info + domain;
+
+		scmi_power_domain_attributes_get(ph, domain, dom, version);
+	}
+
+	pinfo->version = version;
+
+	return ph->set_priv(ph, pinfo);
+}
+
+static const struct scmi_protocol scmi_power = {
+	.id = SCMI_PROTOCOL_POWER,
+	.owner = THIS_MODULE,
+	.instance_init = &scmi_power_protocol_init,
+	.ops = &power_proto_ops,
+	.events = &power_protocol_events,
+};
+
+DEFINE_SCMI_PROTOCOL_REGISTER_UNREGISTER(power, scmi_power)