https://github.com/torvalds/linux
Tip revision: 7d194c2100ad2a6dded545887d02754948ca5241 authored by Linus Torvalds on 20 October 2019, 19:56:22 UTC
Linux 5.4-rc4
Linux 5.4-rc4
Tip revision: 7d194c2
power.c
// SPDX-License-Identifier: GPL-2.0
/*
* System Control and Management Interface (SCMI) Power Protocol
*
* Copyright (C) 2018 ARM Ltd.
*/
#include "common.h"
enum scmi_power_protocol_cmd {
POWER_DOMAIN_ATTRIBUTES = 0x3,
POWER_STATE_SET = 0x4,
POWER_STATE_GET = 0x5,
POWER_STATE_NOTIFY = 0x6,
};
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))
u8 name[SCMI_MAX_STR_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 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 {
int num_domains;
u64 stats_addr;
u32 stats_size;
struct power_dom_info *dom_info;
};
static int scmi_power_attributes_get(const struct scmi_handle *handle,
struct scmi_power_info *pi)
{
int ret;
struct scmi_xfer *t;
struct scmi_msg_resp_power_attributes *attr;
ret = scmi_xfer_get_init(handle, PROTOCOL_ATTRIBUTES,
SCMI_PROTOCOL_POWER, 0, sizeof(*attr), &t);
if (ret)
return ret;
attr = t->rx.buf;
ret = scmi_do_xfer(handle, 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);
}
scmi_xfer_put(handle, t);
return ret;
}
static int
scmi_power_domain_attributes_get(const struct scmi_handle *handle, u32 domain,
struct power_dom_info *dom_info)
{
int ret;
struct scmi_xfer *t;
struct scmi_msg_resp_power_domain_attributes *attr;
ret = scmi_xfer_get_init(handle, POWER_DOMAIN_ATTRIBUTES,
SCMI_PROTOCOL_POWER, sizeof(domain),
sizeof(*attr), &t);
if (ret)
return ret;
put_unaligned_le32(domain, t->tx.buf);
attr = t->rx.buf;
ret = scmi_do_xfer(handle, t);
if (!ret) {
u32 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);
strlcpy(dom_info->name, attr->name, SCMI_MAX_STR_SIZE);
}
scmi_xfer_put(handle, t);
return ret;
}
static int
scmi_power_state_set(const struct scmi_handle *handle, u32 domain, u32 state)
{
int ret;
struct scmi_xfer *t;
struct scmi_power_set_state *st;
ret = scmi_xfer_get_init(handle, POWER_STATE_SET, SCMI_PROTOCOL_POWER,
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 = scmi_do_xfer(handle, t);
scmi_xfer_put(handle, t);
return ret;
}
static int
scmi_power_state_get(const struct scmi_handle *handle, u32 domain, u32 *state)
{
int ret;
struct scmi_xfer *t;
ret = scmi_xfer_get_init(handle, POWER_STATE_GET, SCMI_PROTOCOL_POWER,
sizeof(u32), sizeof(u32), &t);
if (ret)
return ret;
put_unaligned_le32(domain, t->tx.buf);
ret = scmi_do_xfer(handle, t);
if (!ret)
*state = get_unaligned_le32(t->rx.buf);
scmi_xfer_put(handle, t);
return ret;
}
static int scmi_power_num_domains_get(const struct scmi_handle *handle)
{
struct scmi_power_info *pi = handle->power_priv;
return pi->num_domains;
}
static char *scmi_power_name_get(const struct scmi_handle *handle, u32 domain)
{
struct scmi_power_info *pi = handle->power_priv;
struct power_dom_info *dom = pi->dom_info + domain;
return dom->name;
}
static struct scmi_power_ops power_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_protocol_init(struct scmi_handle *handle)
{
int domain;
u32 version;
struct scmi_power_info *pinfo;
scmi_version_get(handle, SCMI_PROTOCOL_POWER, &version);
dev_dbg(handle->dev, "Power Version %d.%d\n",
PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
pinfo = devm_kzalloc(handle->dev, sizeof(*pinfo), GFP_KERNEL);
if (!pinfo)
return -ENOMEM;
scmi_power_attributes_get(handle, pinfo);
pinfo->dom_info = devm_kcalloc(handle->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(handle, domain, dom);
}
handle->power_ops = &power_ops;
handle->power_priv = pinfo;
return 0;
}
static int __init scmi_power_init(void)
{
return scmi_protocol_register(SCMI_PROTOCOL_POWER,
&scmi_power_protocol_init);
}
subsys_initcall(scmi_power_init);