[PATCH 2/7] firmware: arm_scmi: Add SCMIv3.1 Powercap protocol basic support

From: Cristian Marussi
Date: Wed May 04 2022 - 05:37:03 EST


Add support for SCMIv3.1 Powercap protocol, with the exception of Powercap
FastChannels, exposing all the new related Powercap protocol operations as
usual in include/linux/scmi_protocol.h.

Signed-off-by: Cristian Marussi <cristian.marussi@xxxxxxx>
---
drivers/firmware/arm_scmi/Makefile | 2 +-
drivers/firmware/arm_scmi/driver.c | 2 +
drivers/firmware/arm_scmi/powercap.c | 705 ++++++++++++++++++++++++++
drivers/firmware/arm_scmi/protocols.h | 1 +
include/linux/scmi_protocol.h | 120 +++++
5 files changed, 829 insertions(+), 1 deletion(-)
create mode 100644 drivers/firmware/arm_scmi/powercap.c

diff --git a/drivers/firmware/arm_scmi/Makefile b/drivers/firmware/arm_scmi/Makefile
index 8d4afadda38c..a02dc8ce5a7f 100644
--- a/drivers/firmware/arm_scmi/Makefile
+++ b/drivers/firmware/arm_scmi/Makefile
@@ -7,7 +7,7 @@ scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_SMC) += smc.o
scmi-transport-$(CONFIG_ARM_SCMI_HAVE_MSG) += msg.o
scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_VIRTIO) += virtio.o
scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_OPTEE) += optee.o
-scmi-protocols-y = base.o clock.o perf.o power.o reset.o sensors.o system.o voltage.o
+scmi-protocols-y = base.o clock.o perf.o power.o reset.o sensors.o system.o voltage.o powercap.o
scmi-module-objs := $(scmi-bus-y) $(scmi-driver-y) $(scmi-protocols-y) \
$(scmi-transport-y)
obj-$(CONFIG_ARM_SCMI_PROTOCOL) += scmi-module.o
diff --git a/drivers/firmware/arm_scmi/driver.c b/drivers/firmware/arm_scmi/driver.c
index c1922bd650ae..9e07f2ddc721 100644
--- a/drivers/firmware/arm_scmi/driver.c
+++ b/drivers/firmware/arm_scmi/driver.c
@@ -2400,6 +2400,7 @@ static int __init scmi_driver_init(void)
scmi_sensors_register();
scmi_voltage_register();
scmi_system_register();
+ scmi_powercap_register();

return platform_driver_register(&scmi_driver);
}
@@ -2416,6 +2417,7 @@ static void __exit scmi_driver_exit(void)
scmi_sensors_unregister();
scmi_voltage_unregister();
scmi_system_unregister();
+ scmi_powercap_unregister();

scmi_bus_exit();

diff --git a/drivers/firmware/arm_scmi/powercap.c b/drivers/firmware/arm_scmi/powercap.c
new file mode 100644
index 000000000000..7f2dcb944c4e
--- /dev/null
+++ b/drivers/firmware/arm_scmi/powercap.c
@@ -0,0 +1,705 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * System Control and Management Interface (SCMI) Powercap Protocol
+ *
+ * Copyright (C) 2022 ARM Ltd.
+ */
+
+#define pr_fmt(fmt) "SCMI Notifications POWERCAP - " fmt
+
+#include <linux/module.h>
+#include <linux/scmi_protocol.h>
+
+#include "protocols.h"
+#include "notify.h"
+
+enum scmi_powercap_protocol_cmd {
+ POWERCAP_DOMAIN_ATTRIBUTES = 0x3,
+ POWERCAP_CAP_GET = 0x4,
+ POWERCAP_CAP_SET = 0x5,
+ POWERCAP_PAI_GET = 0x6,
+ POWERCAP_PAI_SET = 0x7,
+ POWERCAP_DOMAIN_NAME_GET = 0x8,
+ POWERCAP_MEASUREMENTS_GET = 0x9,
+ POWERCAP_CAP_NOTIFY = 0xa,
+ POWERCAP_MEASUREMENTS_NOTIFY = 0xb,
+ POWERCAP_DESCRIBE_FASTCHANNEL = 0xc,
+};
+
+struct scmi_msg_resp_powercap_domain_attributes {
+ __le32 attributes;
+#define SUPPORTS_POWERCAP_CAP_CHANGE_NOTIFY(x) ((x) & BIT(31))
+#define SUPPORTS_POWERCAP_MEASUREMENTS_CHANGE_NOTIFY(x) ((x) & BIT(30))
+#define SUPPORTS_ASYNC_POWERCAP_CAP_SET(x) ((x) & BIT(29))
+#define SUPPORTS_EXTENDED_NAMES(x) ((x) & BIT(28))
+#define SUPPORTS_POWERCAP_CAP_CONFIGURATION(x) ((x) & BIT(27))
+#define SUPPORTS_POWERCAP_MONITORING(x) ((x) & BIT(26))
+#define SUPPORTS_POWERCAP_PAI_CONFIGURATION(x) ((x) & BIT(25))
+#define POWERCAP_POWER_UNIT(x) \
+ (FIELD_GET(GENMASK(24, 23), (x)))
+#define SUPPORTS_POWER_UNITS_MW(x) \
+ (POWERCAP_POWER_UNIT(x) == 0x2)
+#define SUPPORTS_POWER_UNITS_UW(x) \
+ (POWERCAP_POWER_UNIT(x) == 0x1)
+ u8 name[SCMI_SHORT_NAME_MAX_SIZE];
+ __le32 min_pai;
+ __le32 max_pai;
+ __le32 pai_step;
+ __le32 min_power_cap;
+ __le32 max_power_cap;
+ __le32 power_cap_step;
+ __le32 sustainable_power;
+ __le32 accuracy;
+ __le32 parent_id;
+};
+
+struct scmi_msg_powercap_set_cap_or_pai {
+ __le32 domain;
+ __le32 flags;
+ __le32 value;
+};
+
+struct scmi_msg_resp_powercap_cap_set_complete {
+ __le32 domain;
+ __le32 power_cap;
+};
+
+struct scmi_msg_resp_powercap_meas_get {
+ __le32 power;
+ __le32 pai;
+};
+
+struct scmi_msg_powercap_notify_cap {
+ __le32 domain;
+ __le32 notify_enable;
+};
+
+struct scmi_msg_powercap_notify_thresh {
+ __le32 domain;
+ __le32 notify_enable;
+ __le32 power_thresh_low;
+ __le32 power_thresh_high;
+};
+
+struct scmi_powercap_cap_changed_notify_payld {
+ __le32 agent_id;
+ __le32 domain_id;
+ __le32 power_cap;
+ __le32 pai;
+};
+
+struct scmi_powercap_meas_changed_notify_payld {
+ __le32 agent_id;
+ __le32 domain_id;
+ __le32 power;
+};
+
+struct powercap_info {
+ u32 version;
+ int num_domains;
+ u64 *domain_thresholds;
+ struct scmi_powercap_info *powercaps;
+};
+
+static enum scmi_powercap_protocol_cmd evt_2_cmd[] = {
+ POWERCAP_CAP_NOTIFY,
+ POWERCAP_MEASUREMENTS_NOTIFY,
+};
+
+static int
+scmi_powercap_attributes_get(const struct scmi_protocol_handle *ph,
+ struct powercap_info *pi)
+{
+ int ret;
+ struct scmi_xfer *t;
+
+ ret = ph->xops->xfer_get_init(ph, PROTOCOL_ATTRIBUTES, 0,
+ sizeof(u32), &t);
+ if (ret)
+ return ret;
+
+ ret = ph->xops->do_xfer(ph, t);
+ if (!ret) {
+ u32 attributes;
+
+ attributes = get_unaligned_le32(t->rx.buf);
+ pi->num_domains = FIELD_GET(GENMASK(15, 0), attributes);
+ }
+
+ ph->xops->xfer_put(ph, t);
+ return ret;
+}
+
+static inline int
+scmi_powercap_validate(unsigned int min_val, unsigned int max_val,
+ unsigned int step_val, bool configurable)
+{
+ if (!min_val || !max_val)
+ return -EPROTO;
+
+ if ((configurable && min_val == max_val) ||
+ (!configurable && min_val != max_val))
+ return -EPROTO;
+
+ if (min_val != max_val && !step_val)
+ return -EPROTO;
+
+ return 0;
+}
+
+static int
+scmi_powercap_domain_attributes_get(const struct scmi_protocol_handle *ph,
+ struct powercap_info *pinfo, u32 domain)
+{
+ int ret;
+ u32 flags;
+ struct scmi_xfer *t;
+ struct scmi_powercap_info *dom_info = pinfo->powercaps + domain;
+ struct scmi_msg_resp_powercap_domain_attributes *resp;
+
+ ret = ph->xops->xfer_get_init(ph, POWERCAP_DOMAIN_ATTRIBUTES,
+ sizeof(domain), sizeof(*resp), &t);
+ if (ret)
+ return ret;
+
+ put_unaligned_le32(domain, t->tx.buf);
+ resp = t->rx.buf;
+
+ ret = ph->xops->do_xfer(ph, t);
+ if (!ret) {
+ flags = le32_to_cpu(resp->attributes);
+
+ dom_info->id = domain;
+ dom_info->notify_powercap_cap_change =
+ SUPPORTS_POWERCAP_CAP_CHANGE_NOTIFY(flags);
+ dom_info->notify_powercap_measurement_change =
+ SUPPORTS_POWERCAP_MEASUREMENTS_CHANGE_NOTIFY(flags);
+ dom_info->async_powercap_cap_set =
+ SUPPORTS_ASYNC_POWERCAP_CAP_SET(flags);
+ dom_info->powercap_cap_config =
+ SUPPORTS_POWERCAP_CAP_CONFIGURATION(flags);
+ dom_info->powercap_monitoring =
+ SUPPORTS_POWERCAP_MONITORING(flags);
+ dom_info->powercap_pai_config =
+ SUPPORTS_POWERCAP_PAI_CONFIGURATION(flags);
+ dom_info->powercap_scale_mw =
+ SUPPORTS_POWER_UNITS_MW(flags);
+ dom_info->powercap_scale_uw =
+ SUPPORTS_POWER_UNITS_UW(flags);
+
+ strscpy(dom_info->name, resp->name, SCMI_MAX_STR_SIZE);
+
+ dom_info->min_pai = le32_to_cpu(resp->min_pai);
+ dom_info->max_pai = le32_to_cpu(resp->max_pai);
+ dom_info->pai_step = le32_to_cpu(resp->pai_step);
+ ret = scmi_powercap_validate(dom_info->min_pai,
+ dom_info->max_pai,
+ dom_info->pai_step,
+ dom_info->powercap_pai_config);
+ if (ret) {
+ dev_err(ph->dev,
+ "Platform reported inconsistent PAI config for domain %d - %s\n",
+ dom_info->id, dom_info->name);
+ goto clean;
+ }
+
+ dom_info->min_power_cap = le32_to_cpu(resp->min_power_cap);
+ dom_info->max_power_cap = le32_to_cpu(resp->max_power_cap);
+ dom_info->power_cap_step = le32_to_cpu(resp->power_cap_step);
+ ret = scmi_powercap_validate(dom_info->min_power_cap,
+ dom_info->max_power_cap,
+ dom_info->power_cap_step,
+ dom_info->powercap_cap_config);
+ if (ret) {
+ dev_err(ph->dev,
+ "Platform reported inconsistent CAP config for domain %d - %s\n",
+ dom_info->id, dom_info->name);
+ goto clean;
+ }
+
+ dom_info->sustainable_power =
+ le32_to_cpu(resp->sustainable_power);
+ dom_info->accuracy = le32_to_cpu(resp->accuracy);
+
+ dom_info->parent_id = le32_to_cpu(resp->parent_id);
+ if (dom_info->parent_id != SCMI_POWERCAP_ROOT_ZONE_ID &&
+ (dom_info->parent_id >= pinfo->num_domains ||
+ dom_info->parent_id == dom_info->id)) {
+ dev_err(ph->dev,
+ "Platform reported inconsistent parent ID for domain %d - %s\n",
+ dom_info->id, dom_info->name);
+ ret = -ENODEV;
+ }
+ }
+
+clean:
+ 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 && SUPPORTS_EXTENDED_NAMES(flags))
+ ph->hops->extended_name_get(ph, POWERCAP_DOMAIN_NAME_GET,
+ domain, dom_info->name,
+ SCMI_MAX_STR_SIZE);
+
+ return ret;
+}
+
+static int scmi_powercap_num_domains_get(const struct scmi_protocol_handle *ph)
+{
+ struct powercap_info *pi = ph->get_priv(ph);
+
+ return pi->num_domains;
+}
+
+static const struct scmi_powercap_info *
+scmi_powercap_dom_info_get(const struct scmi_protocol_handle *ph, u32 domain_id)
+{
+ struct powercap_info *pi = ph->get_priv(ph);
+
+ if (domain_id >= pi->num_domains)
+ return NULL;
+
+ return pi->powercaps + domain_id;
+}
+
+static int scmi_powercap_cap_get(const struct scmi_protocol_handle *ph,
+ u32 domain_id, u32 *power_cap)
+{
+ int ret;
+ struct scmi_xfer *t;
+ struct powercap_info *pi = ph->get_priv(ph);
+
+ if (!power_cap || domain_id >= pi->num_domains)
+ return -EINVAL;
+
+ ret = ph->xops->xfer_get_init(ph, POWERCAP_CAP_GET, sizeof(u32),
+ sizeof(u32), &t);
+ if (ret)
+ return ret;
+
+ put_unaligned_le32(domain_id, t->tx.buf);
+ ret = ph->xops->do_xfer(ph, t);
+ if (!ret)
+ *power_cap = get_unaligned_le32(t->rx.buf);
+
+ ph->xops->xfer_put(ph, t);
+
+ return ret;
+}
+
+static int scmi_powercap_cap_set(const struct scmi_protocol_handle *ph,
+ u32 domain_id, u32 power_cap,
+ bool ignore_dresp)
+{
+ int ret;
+ struct scmi_xfer *t;
+ struct scmi_msg_powercap_set_cap_or_pai *msg;
+ const struct scmi_powercap_info *pc;
+
+ pc = scmi_powercap_dom_info_get(ph, domain_id);
+ if (!pc || !pc->powercap_cap_config || !power_cap ||
+ power_cap < pc->min_power_cap ||
+ power_cap > pc->max_power_cap)
+ return -EINVAL;
+
+ ret = ph->xops->xfer_get_init(ph, POWERCAP_CAP_SET,
+ sizeof(*msg), 0, &t);
+ if (ret)
+ return ret;
+
+ msg = t->tx.buf;
+ msg->domain = cpu_to_le32(domain_id);
+ msg->flags = cpu_to_le32(!!pc->async_powercap_cap_set << 1 |
+ !!ignore_dresp);
+ msg->value = cpu_to_le32(power_cap);
+
+ if (!pc->async_powercap_cap_set || ignore_dresp) {
+ ret = ph->xops->do_xfer(ph, t);
+ } else {
+ ret = ph->xops->do_xfer_with_response(ph, t);
+ if (!ret) {
+ struct scmi_msg_resp_powercap_cap_set_complete *resp;
+
+ resp = t->rx.buf;
+ if (le32_to_cpu(resp->domain) == domain_id)
+ dev_dbg(ph->dev,
+ "Powercap ID %d CAP set async to %u\n",
+ domain_id,
+ get_unaligned_le32(&resp->power_cap));
+ else
+ ret = -EPROTO;
+ }
+ }
+
+ ph->xops->xfer_put(ph, t);
+ return ret;
+}
+
+static int scmi_powercap_pai_get(const struct scmi_protocol_handle *ph,
+ u32 domain_id, u32 *pai)
+{
+ int ret;
+ struct scmi_xfer *t;
+ struct powercap_info *pi = ph->get_priv(ph);
+
+ if (!pai || domain_id >= pi->num_domains)
+ return -EINVAL;
+
+ ret = ph->xops->xfer_get_init(ph, POWERCAP_PAI_GET, sizeof(u32),
+ sizeof(u32), &t);
+ if (ret)
+ return ret;
+
+ put_unaligned_le32(domain_id, t->tx.buf);
+ ret = ph->xops->do_xfer(ph, t);
+ if (!ret)
+ *pai = get_unaligned_le32(t->rx.buf);
+
+ ph->xops->xfer_put(ph, t);
+
+ return ret;
+}
+
+static int scmi_powercap_pai_set(const struct scmi_protocol_handle *ph,
+ u32 domain_id, u32 pai)
+{
+ int ret;
+ struct scmi_xfer *t;
+ struct scmi_msg_powercap_set_cap_or_pai *msg;
+ const struct scmi_powercap_info *pc;
+
+ pc = scmi_powercap_dom_info_get(ph, domain_id);
+ if (!pc || !pc->powercap_pai_config || !pai ||
+ pai < pc->min_pai || pai > pc->max_pai)
+ return -EINVAL;
+
+ ret = ph->xops->xfer_get_init(ph, POWERCAP_PAI_SET,
+ sizeof(*msg), 0, &t);
+ if (ret)
+ return ret;
+
+ msg = t->tx.buf;
+ msg->domain = cpu_to_le32(domain_id);
+ msg->flags = cpu_to_le32(0);
+ msg->value = cpu_to_le32(pai);
+
+ ret = ph->xops->do_xfer(ph, t);
+
+ ph->xops->xfer_put(ph, t);
+ return ret;
+}
+
+static int scmi_powercap_measurements_get(const struct scmi_protocol_handle *ph,
+ u32 domain_id, u32 *average_power,
+ u32 *pai)
+{
+ int ret;
+ struct scmi_xfer *t;
+ struct scmi_msg_resp_powercap_meas_get *resp;
+ const struct scmi_powercap_info *pc;
+
+ pc = scmi_powercap_dom_info_get(ph, domain_id);
+ if (!pc || !pc->powercap_monitoring || !pai || !average_power)
+ return -EINVAL;
+
+ ret = ph->xops->xfer_get_init(ph, POWERCAP_MEASUREMENTS_GET,
+ sizeof(u32), sizeof(*resp), &t);
+ if (ret)
+ return ret;
+
+ resp = t->rx.buf;
+ put_unaligned_le32(domain_id, t->tx.buf);
+ ret = ph->xops->do_xfer(ph, t);
+ if (!ret) {
+ *average_power = le32_to_cpu(resp->power);
+ *pai = le32_to_cpu(resp->pai);
+ }
+
+ ph->xops->xfer_put(ph, t);
+ return ret;
+}
+
+static int
+scmi_powercap_measurements_threshold_get(const struct scmi_protocol_handle *ph,
+ u32 domain_id, u32 *power_thresh_low,
+ u32 *power_thresh_high)
+{
+ struct powercap_info *pi = ph->get_priv(ph);
+
+ if (!power_thresh_low || !power_thresh_high ||
+ domain_id >= pi->num_domains)
+ return -EINVAL;
+
+ *power_thresh_low = lower_32_bits(pi->domain_thresholds[domain_id]);
+ *power_thresh_high = upper_32_bits(pi->domain_thresholds[domain_id]);
+
+ return 0;
+}
+
+static int
+scmi_powercap_measurements_threshold_set(const struct scmi_protocol_handle *ph,
+ u32 domain_id, u32 power_thresh_low,
+ u32 power_thresh_high)
+{
+ struct powercap_info *pi = ph->get_priv(ph);
+
+ if (domain_id >= pi->num_domains)
+ return -EINVAL;
+
+ pi->domain_thresholds[domain_id] =
+ (FIELD_PREP(GENMASK(63, 32), power_thresh_high) |
+ FIELD_PREP(GENMASK(31, 0), power_thresh_low));
+
+ return 0;
+}
+
+static const struct scmi_powercap_proto_ops powercap_proto_ops = {
+ .num_domains_get = scmi_powercap_num_domains_get,
+ .info_get = scmi_powercap_dom_info_get,
+ .cap_get = scmi_powercap_cap_get,
+ .cap_set = scmi_powercap_cap_set,
+ .pai_get = scmi_powercap_pai_get,
+ .pai_set = scmi_powercap_pai_set,
+ .measurements_get = scmi_powercap_measurements_get,
+ .measurements_threshold_set = scmi_powercap_measurements_threshold_set,
+ .measurements_threshold_get = scmi_powercap_measurements_threshold_get,
+};
+
+static int scmi_powercap_notify(const struct scmi_protocol_handle *ph,
+ u32 domain, int message_id, bool enable)
+{
+ int ret;
+ struct scmi_xfer *t;
+
+ switch (message_id) {
+ case POWERCAP_CAP_NOTIFY:
+ {
+ struct scmi_msg_powercap_notify_cap *notify;
+
+ ret = ph->xops->xfer_get_init(ph, message_id,
+ sizeof(*notify), 0, &t);
+ if (ret)
+ return ret;
+
+ notify = t->tx.buf;
+ notify->domain = cpu_to_le32(domain);
+ notify->notify_enable = cpu_to_le32(enable ? BIT(0) : 0);
+ break;
+ }
+ case POWERCAP_MEASUREMENTS_NOTIFY:
+ {
+ u32 low, high;
+ struct scmi_msg_powercap_notify_thresh *notify;
+
+ /*
+ * Note that we have to pick the most recently configured
+ * thresholds to build a proper POWERCAP_MEASUREMENTS_NOTIFY
+ * enable request and we fail, complaining, if no thresholds
+ * were ever set, since this is an indication the API has been
+ * used wrongly.
+ */
+ ret = scmi_powercap_measurements_threshold_get(ph, domain,
+ &low, &high);
+ if (ret)
+ return ret;
+
+ if (enable && !low && !high) {
+ dev_err(ph->dev,
+ "Invalid Measurements Notify thresholds: %u/%u\n",
+ low, high);
+ return -EINVAL;
+ }
+
+ ret = ph->xops->xfer_get_init(ph, message_id,
+ sizeof(*notify), 0, &t);
+ if (ret)
+ return ret;
+
+ notify = t->tx.buf;
+ notify->domain = cpu_to_le32(domain);
+ notify->notify_enable = cpu_to_le32(enable ? BIT(0) : 0);
+ notify->power_thresh_low = cpu_to_le32(low);
+ notify->power_thresh_high = cpu_to_le32(high);
+ break;
+ }
+ default:
+ return -EINVAL;
+ }
+
+ ret = ph->xops->do_xfer(ph, t);
+
+ ph->xops->xfer_put(ph, t);
+ return ret;
+}
+
+static int
+scmi_powercap_set_notify_enabled(const struct scmi_protocol_handle *ph,
+ u8 evt_id, u32 src_id, bool enable)
+{
+ int ret, cmd_id;
+
+ if (evt_id >= ARRAY_SIZE(evt_2_cmd))
+ return -EINVAL;
+
+ cmd_id = evt_2_cmd[evt_id];
+ ret = scmi_powercap_notify(ph, src_id, cmd_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_powercap_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)
+{
+ void *rep = NULL;
+
+ switch (evt_id) {
+ case SCMI_EVENT_POWERCAP_CAP_CHANGED:
+ {
+ const struct scmi_powercap_cap_changed_notify_payld *p = payld;
+ struct scmi_powercap_cap_changed_report *r = report;
+
+ if (sizeof(*p) != payld_sz)
+ break;
+
+ r->timestamp = timestamp;
+ r->agent_id = le32_to_cpu(p->agent_id);
+ r->domain_id = le32_to_cpu(p->domain_id);
+ r->power_cap = le32_to_cpu(p->power_cap);
+ r->pai = le32_to_cpu(p->pai);
+ *src_id = r->domain_id;
+ rep = r;
+ break;
+ }
+ case SCMI_EVENT_POWERCAP_MEASUREMENTS_CHANGED:
+ {
+ const struct scmi_powercap_meas_changed_notify_payld *p = payld;
+ struct scmi_powercap_meas_changed_report *r = report;
+
+ if (sizeof(*p) != payld_sz)
+ break;
+
+ r->timestamp = timestamp;
+ r->agent_id = le32_to_cpu(p->agent_id);
+ r->domain_id = le32_to_cpu(p->domain_id);
+ r->power = le32_to_cpu(p->power);
+ *src_id = r->domain_id;
+ rep = r;
+ break;
+ }
+ default:
+ break;
+ }
+
+ return rep;
+}
+
+static int
+scmi_powercap_get_num_sources(const struct scmi_protocol_handle *ph)
+{
+ struct powercap_info *pi = ph->get_priv(ph);
+
+ if (!pi)
+ return -EINVAL;
+
+ return pi->num_domains;
+}
+
+static const struct scmi_event powercap_events[] = {
+ {
+ .id = SCMI_EVENT_POWERCAP_CAP_CHANGED,
+ .max_payld_sz =
+ sizeof(struct scmi_powercap_cap_changed_notify_payld),
+ .max_report_sz =
+ sizeof(struct scmi_powercap_cap_changed_report),
+ },
+ {
+ .id = SCMI_EVENT_POWERCAP_MEASUREMENTS_CHANGED,
+ .max_payld_sz =
+ sizeof(struct scmi_powercap_meas_changed_notify_payld),
+ .max_report_sz =
+ sizeof(struct scmi_powercap_meas_changed_report),
+ },
+};
+
+static const struct scmi_event_ops powercap_event_ops = {
+ .get_num_sources = scmi_powercap_get_num_sources,
+ .set_notify_enabled = scmi_powercap_set_notify_enabled,
+ .fill_custom_report = scmi_powercap_fill_custom_report,
+};
+
+static const struct scmi_protocol_events powercap_protocol_events = {
+ .queue_sz = SCMI_PROTO_QUEUE_SZ,
+ .ops = &powercap_event_ops,
+ .evts = powercap_events,
+ .num_events = ARRAY_SIZE(powercap_events),
+};
+
+static int
+scmi_powercap_protocol_init(const struct scmi_protocol_handle *ph)
+{
+ int domain, ret;
+ u32 version;
+ struct powercap_info *pinfo;
+
+ ret = ph->xops->version_get(ph, &version);
+ if (ret)
+ return ret;
+
+ dev_dbg(ph->dev, "Powercap 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_powercap_attributes_get(ph, pinfo);
+ if (ret)
+ return ret;
+
+ pinfo->powercaps = devm_kcalloc(ph->dev, pinfo->num_domains,
+ sizeof(*pinfo->powercaps),
+ GFP_KERNEL);
+ if (!pinfo->powercaps)
+ return -ENOMEM;
+
+ /*
+ * Note that any failure in retrieving any domain attribute leads to
+ * the whole Powercap protocol initialization failure: this way the
+ * reported Powercap domains are all assured, when accessed, to be well
+ * formed and correlated by sane parent-child relationship (if any).
+ */
+ for (domain = 0; domain < pinfo->num_domains; domain++) {
+ ret = scmi_powercap_domain_attributes_get(ph, pinfo, domain);
+ if (ret)
+ return ret;
+ }
+
+ pinfo->domain_thresholds = devm_kcalloc(ph->dev, pinfo->num_domains,
+ sizeof(*pinfo->domain_thresholds),
+ GFP_KERNEL);
+ if (!pinfo->domain_thresholds)
+ return -ENOMEM;
+
+ pinfo->version = version;
+
+ return ph->set_priv(ph, pinfo);
+}
+
+static const struct scmi_protocol scmi_powercap = {
+ .id = SCMI_PROTOCOL_POWERCAP,
+ .owner = THIS_MODULE,
+ .instance_init = &scmi_powercap_protocol_init,
+ .ops = &powercap_proto_ops,
+ .events = &powercap_protocol_events,
+};
+
+DEFINE_SCMI_PROTOCOL_REGISTER_UNREGISTER(powercap, scmi_powercap)
diff --git a/drivers/firmware/arm_scmi/protocols.h b/drivers/firmware/arm_scmi/protocols.h
index 73304af5ec4a..c774e37062e9 100644
--- a/drivers/firmware/arm_scmi/protocols.h
+++ b/drivers/firmware/arm_scmi/protocols.h
@@ -314,5 +314,6 @@ DECLARE_SCMI_REGISTER_UNREGISTER(reset);
DECLARE_SCMI_REGISTER_UNREGISTER(sensors);
DECLARE_SCMI_REGISTER_UNREGISTER(voltage);
DECLARE_SCMI_REGISTER_UNREGISTER(system);
+DECLARE_SCMI_REGISTER_UNREGISTER(powercap);

#endif /* _SCMI_PROTOCOLS_H */
diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h
index 1c58646ba381..0216f70d57a8 100644
--- a/include/linux/scmi_protocol.h
+++ b/include/linux/scmi_protocol.h
@@ -559,6 +559,109 @@ struct scmi_voltage_proto_ops {
s32 *volt_uV);
};

+/**
+ * struct scmi_powercap_info - Describe one available Powercap domain
+ *
+ * @id: Domain ID as advertised by the platform.
+ * @notify_powercap_cap_change: CAP change notification support.
+ * @otify_powercap_measurement_change: MEASUREMENTS change notifications
+ * support.
+ * @async_powercap_cap_set: Asynchronous CAP set support.
+ * @powercap_cap_config: CAP configuration support.
+ * @powercap_monitoring: Monitoring (measurements) support.
+ * @powercap_pai_config: PAI configuration support.
+ * @powercap_scale_mw: Domain reports power data in milliwatt units.
+ * @powercap_scale_uw: Domain reports power data in microwatt units.
+ * Note that, when both @powercap_scale_mw and
+ * @powercap_scale_uw are set to false, the domain
+ * reports power data on an abstract linear scale.
+ * @name: name assigned to the Powercap Domain by platform.
+ * @min_pai: Minimum configurable PAI.
+ * @max_pai: Maximum configurable PAI.
+ * @pai_step: Step size between two consecutive PAI values.
+ * @min_power_cap: Minimum configurable CAP.
+ * @max_power_cap: Maximum configurable CAP.
+ * @power_cap_step: Step size between two consecutive CAP values.
+ * @sustainable_power: Maximum sustainable power consumption for this domain
+ * under normal conditions.
+ * @accuracy: The accuracy with which the power is measured and reported in
+ * integral multiples of 0.001 percent.
+ * @parent_id: Identifier of the containing parent power capping domain, or the
+ * value 0xFFFFFFFF if this powercap domain is a root domain not
+ * contained in any other domain.
+ */
+struct scmi_powercap_info {
+ unsigned int id;
+ bool notify_powercap_cap_change;
+ bool notify_powercap_measurement_change;
+ bool async_powercap_cap_set;
+ bool powercap_cap_config;
+ bool powercap_monitoring;
+ bool powercap_pai_config;
+ bool powercap_scale_mw;
+ bool powercap_scale_uw;
+ char name[SCMI_MAX_STR_SIZE];
+ unsigned int min_pai;
+ unsigned int max_pai;
+ unsigned int pai_step;
+ unsigned int min_power_cap;
+ unsigned int max_power_cap;
+ unsigned int power_cap_step;
+ unsigned int sustainable_power;
+ unsigned int accuracy;
+#define SCMI_POWERCAP_ROOT_ZONE_ID 0xFFFFFFFFUL
+ unsigned int parent_id;
+};
+
+/**
+ * struct scmi_powercap_proto_ops - represents the various operations provided
+ * by SCMI Powercap Protocol
+ *
+ * @num_domains_get: get the count of powercap domains provided by SCMI.
+ * @info_get: get the information for the specified domain.
+ * @cap_get: get the current CAP value for the specified domain.
+ * @cap_set: set the CAP value for the specified domain to the provided value;
+ * if the domain supports setting the CAP with an asynchronous command
+ * this request will finally trigger an asynchronous transfer, but, if
+ * @ignore_dresp here is set to true, this call will anyway return
+ * immediately without waiting for the related delayed response.
+ * @pai_get: get the current PAI value for the specified domain.
+ * @pai_set: set the PAI value for the specified domain to the provided value.
+ * @measurements_get: retrieve the current average power measurements for the
+ * specified domain and the related PAI upon which is
+ * calculated.
+ * @measurements_threshold_set: set the desired low and high power thresholds
+ * to be used when registering for notification
+ * of type POWERCAP_MEASUREMENTS_NOTIFY with this
+ * powercap domain.
+ * Note that this must be called before registering
+ * the callback with the usual @scmi_notify_ops.
+ * @measurements_threshold_get: get the currently configured low and high power
+ * thresholds used when registering callbacks for
+ * notification POWERCAP_MEASUREMENTS_NOTIFY.
+ */
+struct scmi_powercap_proto_ops {
+ int (*num_domains_get)(const struct scmi_protocol_handle *ph);
+ const struct scmi_powercap_info __must_check *(*info_get)
+ (const struct scmi_protocol_handle *ph, u32 domain_id);
+ int (*cap_get)(const struct scmi_protocol_handle *ph, u32 domain_id,
+ u32 *power_cap);
+ int (*cap_set)(const struct scmi_protocol_handle *ph, u32 domain_id,
+ u32 power_cap, bool ignore_dresp);
+ int (*pai_get)(const struct scmi_protocol_handle *ph, u32 domain_id,
+ u32 *pai);
+ int (*pai_set)(const struct scmi_protocol_handle *ph, u32 domain_id,
+ u32 pai);
+ int (*measurements_get)(const struct scmi_protocol_handle *ph,
+ u32 domain_id, u32 *average_power, u32 *pai);
+ int (*measurements_threshold_set)(const struct scmi_protocol_handle *ph,
+ u32 domain_id, u32 power_thresh_low,
+ u32 power_thresh_high);
+ int (*measurements_threshold_get)(const struct scmi_protocol_handle *ph,
+ u32 domain_id, u32 *power_thresh_low,
+ u32 *power_thresh_high);
+};
+
/**
* struct scmi_notify_ops - represents notifications' operations provided by
* SCMI core
@@ -660,6 +763,7 @@ enum scmi_std_protocol {
SCMI_PROTOCOL_SENSOR = 0x15,
SCMI_PROTOCOL_RESET = 0x16,
SCMI_PROTOCOL_VOLTAGE = 0x17,
+ SCMI_PROTOCOL_POWERCAP = 0x18,
};

enum scmi_system_events {
@@ -761,6 +865,8 @@ enum scmi_notification_events {
SCMI_EVENT_RESET_ISSUED = 0x0,
SCMI_EVENT_BASE_ERROR_EVENT = 0x0,
SCMI_EVENT_SYSTEM_POWER_STATE_NOTIFIER = 0x0,
+ SCMI_EVENT_POWERCAP_CAP_CHANGED = 0x0,
+ SCMI_EVENT_POWERCAP_MEASUREMENTS_CHANGED = 0x1,
};

struct scmi_power_state_changed_report {
@@ -829,4 +935,18 @@ struct scmi_base_error_report {
unsigned long long reports[];
};

+struct scmi_powercap_cap_changed_report {
+ ktime_t timestamp;
+ unsigned int agent_id;
+ unsigned int domain_id;
+ unsigned int power_cap;
+ unsigned int pai;
+};
+
+struct scmi_powercap_meas_changed_report {
+ ktime_t timestamp;
+ unsigned int agent_id;
+ unsigned int domain_id;
+ unsigned int power;
+};
#endif /* _LINUX_SCMI_PROTOCOL_H */
--
2.32.0