path: root/drivers/firmware/arm_scmi/powercap.c

// 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/bitfield.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/scmi_protocol.h>

#include <trace/events/scmi.h>

#include "protocols.h"
#include "notify.h"

/* Updated only after ALL the mandatory features for that version are merged */
#define SCMI_PROTOCOL_SUPPORTED_VERSION		0x20000

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,
};

enum {
	POWERCAP_FC_CAP,
	POWERCAP_FC_PAI,
	POWERCAP_FC_MAX,
};

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 SUPPORTS_POWERCAP_FASTCHANNELS(x)		((x) & BIT(22))
#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;
#define CAP_SET_ASYNC		BIT(1)
#define CAP_SET_IGNORE_DRESP	BIT(0)
	__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 scmi_powercap_state {
	bool enabled;
	u32 last_pcap;
	bool meas_notif_enabled;
	u64 thresholds;
#define THRESH_LOW(p, id)				\
	(lower_32_bits((p)->states[(id)].thresholds))
#define THRESH_HIGH(p, id)				\
	(upper_32_bits((p)->states[(id)].thresholds))
};

struct powercap_info {
	u32 version;
	int num_domains;
	bool notify_cap_cmd;
	bool notify_measurements_cmd;
	struct scmi_powercap_state *states;
	struct scmi_powercap_info *powercaps;
};

static enum scmi_powercap_protocol_cmd evt_2_cmd[] = {
	POWERCAP_CAP_NOTIFY,
	POWERCAP_MEASUREMENTS_NOTIFY,
};

static int scmi_powercap_notify(const struct scmi_protocol_handle *ph,
				u32 domain, int message_id, bool enable);

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);

	if (!ret) {
		if (!ph->hops->protocol_msg_check(ph,
						  POWERCAP_CAP_NOTIFY, NULL))
			pi->notify_cap_cmd = true;

		if (!ph->hops->protocol_msg_check(ph,
						  POWERCAP_MEASUREMENTS_NOTIFY,
						  NULL))
			pi->notify_measurements_cmd = true;
	}

	return ret;
}

static inline int
scmi_powercap_validate(unsigned int min_val, unsigned int max_val,
		       unsigned int step_val, bool configurable)</