blob: 2175ffd6cef534870a8e7f41a66d30981a7bc845 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0
/*
* System Control and Management Interface (SCMI) Voltage Protocol
*
* Copyright (C) 2020-2022 ARM Ltd.
*/
#include <linux/module.h>
#include <linux/scmi_protocol.h>
#include "protocols.h"
/* Updated only after ALL the mandatory features for that version are merged */
#define SCMI_PROTOCOL_SUPPORTED_VERSION 0x20000
#define VOLTAGE_DOMS_NUM_MASK GENMASK(15, 0)
#define REMAINING_LEVELS_MASK GENMASK(31, 16)
#define RETURNED_LEVELS_MASK GENMASK(11, 0)
enum scmi_voltage_protocol_cmd {
VOLTAGE_DOMAIN_ATTRIBUTES = 0x3,
VOLTAGE_DESCRIBE_LEVELS = 0x4,
VOLTAGE_CONFIG_SET = 0x5,
VOLTAGE_CONFIG_GET = 0x6,
VOLTAGE_LEVEL_SET = 0x7,
VOLTAGE_LEVEL_GET = 0x8,
VOLTAGE_DOMAIN_NAME_GET = 0x09,
};
#define NUM_VOLTAGE_DOMAINS(x) ((u16)(FIELD_GET(VOLTAGE_DOMS_NUM_MASK, (x))))
struct scmi_msg_resp_domain_attributes {
__le32 attr;
#define SUPPORTS_ASYNC_LEVEL_SET(x) ((x) & BIT(31))
#define SUPPORTS_EXTENDED_NAMES(x) ((x) & BIT(30))
u8 name[SCMI_SHORT_NAME_MAX_SIZE];
};
struct scmi_msg_cmd_describe_levels {
__le32 domain_id;
__le32 level_index;
};
struct scmi_msg_resp_describe_levels {
__le32 flags;
#define NUM_REMAINING_LEVELS(f) ((u16)(FIELD_GET(REMAINING_LEVELS_MASK, (f))))
#define NUM_RETURNED_LEVELS(f) ((u16)(FIELD_GET(RETURNED_LEVELS_MASK, (f))))
#define SUPPORTS_SEGMENTED_LEVELS(f) ((f) & BIT(12))
__le32 voltage[];
};
struct scmi_msg_cmd_config_set {
__le32 domain_id;
__le32 config;
};
struct scmi_msg_cmd_level_set {
__le32 domain_id;
__le32 flags;
__le32 voltage_level;
};
struct scmi_resp_voltage_level_set_complete {
__le32 domain_id;
__le32 voltage_level;
};
struct voltage_info {
unsigned int version;
unsigned int num_domains;
struct scmi_voltage_info *domains;
};
static int scmi_protocol_attributes_get(const struct scmi_protocol_handle *ph,
struct voltage_info *vinfo)
{
int ret;
struct scmi_xfer *t;
ret = ph->xops->xfer_get_init(ph, PROTOCOL_ATTRIBUTES, 0,
sizeof(__le32), &t);
if (ret)
return ret;
ret = ph->xops->do_xfer(ph, t);
if (!ret)
vinfo->num_domains =
NUM_VOLTAGE_DOMAINS(get_unaligned_le32(t->rx.buf));
ph->xops->xfer_put(ph, t);
return ret;
}
static int scmi_init_voltage_levels(struct device *dev,
struct scmi_voltage_info *v,
u32 num_returned, u32 num_remaining,
bool segmented)
{
u32 num_levels;
num_levels = num_returned + num_remaining;
/*
* segmented levels entries are represented by a single triplet
* returned all in one go.
*/
if (!num_levels ||
(segmented && (num_remaining || num_returned != 3))) {
dev_err(dev,
"Invalid level descriptor(%d/%d/%d) for voltage dom %d\n",
num_levels, num_returned, num_remaining, v->id);
return -EINVAL;
}
v->levels_uv = devm_kcalloc(dev, num_levels, sizeof(u32), GFP_KERNEL);
if (!v->levels_uv)
return -ENOMEM;
v->num_levels = num_levels;
v->segmented = segmented;
return 0;
}
struct scmi_volt_ipriv {
struct device *dev;
struct scmi_voltage_info *v;
};
static void iter_volt_levels_prepare_message(void *message,
unsigned int desc_index,
const void *priv)
{
struct scmi_msg_cmd_describe_levels *msg = message;
const struct scmi_volt_ipriv *p = priv;
msg->domain_id = cpu_to_le32(p->v->id);
msg->level_index = cpu_to_le32(desc_index);
}
static int iter_volt_levels_update_state(struct scmi_iterator_state *st,
const void *response, void *priv)
{
int ret = 0;
u32 flags;
const struct scmi_msg_resp_describe_levels *r = response;
struct scmi_volt_ipriv *p = priv;
flags = le32_to_cpu(r->flags);
st->num_returned = NUM_RETURNED_LEVELS(flags);
st->num_remaining = NUM_REMAINING_LEVELS(flags);
/* Allocate space for num_levels if not already done */
if (!p->v->num_levels) {
ret = scmi_init_voltage_levels(p->dev, p->v, st->num_returned,
st->num_remaining,
SUPPORTS_SEGMENTED_LEVELS(flags));
if (!ret)
st->max_resources = p->v->num_levels;
}
return ret;
}
static int
iter_volt_levels_process_response(const struct scmi_protocol_handle *ph,
const void *response,
struct scmi_iterator_state *st, void *priv)
{
s32 val;
const struct scmi_msg_resp_describe_levels *r = response;
struct scmi_volt_ipriv *p = priv;
val = (s32)le32_to_cpu(r->voltage[st->loop_idx]);
p->v->levels_uv[st->desc_index + st->loop_idx] = val;
if (val < 0)
p->v->negative_volts_allowed = true;
return 0;
}
static int scmi_voltage_levels_get(const struct scmi_protocol_handle *ph,
struct scmi_voltage_info *v)
{
int ret;
void *iter;
struct scmi_iterator_ops ops = {
.prepare_message = iter_volt_levels_prepare_message,
.update_state = iter_volt_levels_update_state,
.process_response = iter_volt_levels_process_response,
};
struct scmi_volt_ipriv vpriv = {
.dev = ph->dev,
.v = v,
};
iter = ph->hops->iter_response_init(ph, &ops, v->num_levels,
VOLTAGE_DESCRIBE_LEVELS,
sizeof(struct scmi_msg_cmd_describe_levels),
&vpriv);
if (IS_ERR(iter))
return PTR_ERR(iter);
ret = ph->hops->iter_response_run(iter);
if (ret) {
v->num_levels = 0;
devm_kfree(ph->dev, v->levels_uv);
}
return ret;
}
static int scmi_voltage_descriptors_get(const struct scmi_protocol_handle *ph,
struct voltage_info *vinfo)
{
int ret, dom;
struct scmi_xfer *td;
struct scmi_msg_resp_domain_attributes *resp_dom;
ret = ph->xops->xfer_get_init(ph, VOLTAGE_DOMAIN_ATTRIBUTES,
sizeof(__le32), sizeof(*resp_dom), &td);
if (ret)
return ret;
resp_dom = td->rx.buf;
for (dom = 0; dom < vinfo->num_domains; dom++) {
u32 attributes;
struct scmi_voltage_info *v;
/* Retrieve domain attributes at first ... */
put_unaligned_le32(dom, td->tx.buf);
/* Skip domain on comms error */
if (ph->xops->do_xfer(ph, td))
continue;
v = vinfo->domains + dom;
v->id = dom;
attributes = le32_to_cpu(resp_dom->attr);
strscpy(v->name, resp_dom->name, SCMI_SHORT_NAME_MAX_SIZE);
/*
* If supported overwrite short name with the extended one;
* on error just carry on and use already provided short name.
*/
if (PROTOCOL_REV_MAJOR(vinfo->version) >= 0x2) {
if (SUPPORTS_EXTENDED_NAMES(attributes))
ph->hops->extended_name_get(ph,
VOLTAGE_DOMAIN_NAME_GET,
v->id, NULL, v->name,
SCMI_MAX_STR_SIZE);
if (SUPPORTS_ASYNC_LEVEL_SET(attributes))
v->async_level_set = true;
}
/* Skip invalid voltage descriptors */
scmi_voltage_levels_get(ph, v);
}
ph->xops->xfer_put(ph, td);
return ret;
}
static int __scmi_voltage_get_u32(const struct scmi_protocol_handle *ph,
u8 cmd_id, u32 domain_id, u32 *value)
{
int ret;
struct scmi_xfer *t;
struct voltage_info *vinfo = ph->get_priv(ph);
if (domain_id >= vinfo->num_domains)
return -EINVAL;
ret = ph->xops->xfer_get_init(ph, cmd_id, sizeof(__le32), 0, &t);
if (ret)
return ret;
put_unaligned_le32(domain_id, t->tx.buf);
ret = ph->xops->do_xfer(ph, t);
if (!ret)
*value = get_unaligned_le32(t->rx.buf);
ph->xops->xfer_put(ph, t);
return ret;
}
static int scmi_voltage_config_set(const struct scmi_protocol_handle *ph,
u32 domain_id, u32 config)
{
int ret;
struct scmi_xfer *t;
struct voltage_info *vinfo = ph->get_priv(ph);
struct scmi_msg_cmd_config_set *cmd;
if (domain_id >= vinfo->num_domains)
return -EINVAL;
ret = ph->xops->xfer_get_init(ph, VOLTAGE_CONFIG_SET,
sizeof(*cmd), 0, &t);
if (ret)
return ret;
cmd = t->tx.buf;
cmd->domain_id = cpu_to_le32(domain_id);
cmd->config = cpu_to_le32(config & GENMASK(3, 0));
ret = ph->xops->do_xfer(ph, t);
ph->xops->xfer_put(ph, t);
return ret;
}
static int scmi_voltage_config_get(const struct scmi_protocol_handle *ph,
u32 domain_id, u32 *config)
{
return __scmi_voltage_get_u32(ph, VOLTAGE_CONFIG_GET,
domain_id, config);
}
static int scmi_voltage_level_set(const struct scmi_protocol_handle *ph,
u32 domain_id,
enum scmi_voltage_level_mode mode,
s32 volt_uV)
{
int ret;
struct scmi_xfer *t;
struct voltage_info *vinfo = ph->get_priv(ph);
struct scmi_msg_cmd_level_set *cmd;
struct scmi_voltage_info *v;
if (domain_id >= vinfo->num_domains)
return -EINVAL;
ret = ph->xops->xfer_get_init(ph, VOLTAGE_LEVEL_SET,
sizeof(*cmd), 0, &t);
if (ret)
return ret;
v = vinfo->domains + domain_id;
cmd = t->tx.buf;
cmd->domain_id = cpu_to_le32(domain_id);
cmd->voltage_level = cpu_to_le32(volt_uV);
if (!v->async_level_set || mode != SCMI_VOLTAGE_LEVEL_SET_AUTO) {
cmd->flags = cpu_to_le32(0x0);
ret = ph->xops->do_xfer(ph, t);
} else {
cmd->flags = cpu_to_le32(0x1);
ret = ph->xops->do_xfer_with_response(ph, t);
if (!ret) {
struct scmi_resp_voltage_level_set_complete *resp;
resp = t->rx.buf;
if (le32_to_cpu(resp->domain_id) == domain_id)
dev_dbg(ph->dev,
"Voltage domain %d set async to %d\n",
v->id,
le32_to_cpu(resp->voltage_level));
else
ret = -EPROTO;
}
}
ph->xops->xfer_put(ph, t);
return ret;
}
static int scmi_voltage_level_get(const struct scmi_protocol_handle *ph,
u32 domain_id, s32 *volt_uV)
{
return __scmi_voltage_get_u32(ph, VOLTAGE_LEVEL_GET,
domain_id, (u32 *)volt_uV);
}
static const struct scmi_voltage_info * __must_check
scmi_voltage_info_get(const struct scmi_protocol_handle *ph, u32 domain_id)
{
struct voltage_info *vinfo = ph->get_priv(ph);
if (domain_id >= vinfo->num_domains ||
!vinfo->domains[domain_id].num_levels)
return NULL;
return vinfo->domains + domain_id;
}
static int scmi_voltage_domains_num_get(const struct scmi_protocol_handle *ph)
{
struct voltage_info *vinfo = ph->get_priv(ph);
return vinfo->num_domains;
}
static struct scmi_voltage_proto_ops voltage_proto_ops = {
.num_domains_get = scmi_voltage_domains_num_get,
.info_get = scmi_voltage_info_get,
.config_set = scmi_voltage_config_set,
.config_get = scmi_voltage_config_get,
.level_set = scmi_voltage_level_set,
.level_get = scmi_voltage_level_get,
};
static int scmi_voltage_protocol_init(const struct scmi_protocol_handle *ph)
{
int ret;
u32 version;
struct voltage_info *vinfo;
ret = ph->xops->version_get(ph, &version);
if (ret)
return ret;
dev_dbg(ph->dev, "Voltage Version %d.%d\n",
PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version));
vinfo = devm_kzalloc(ph->dev, sizeof(*vinfo), GFP_KERNEL);
if (!vinfo)
return -ENOMEM;
vinfo->version = version;
ret = scmi_protocol_attributes_get(ph, vinfo);
if (ret)
return ret;
if (vinfo->num_domains) {
vinfo->domains = devm_kcalloc(ph->dev, vinfo->num_domains,
sizeof(*vinfo->domains),
GFP_KERNEL);
if (!vinfo->domains)
return -ENOMEM;
ret = scmi_voltage_descriptors_get(ph, vinfo);
if (ret)
return ret;
} else {
dev_warn(ph->dev, "No Voltage domains found.\n");
}
return ph->set_priv(ph, vinfo, version);
}
static const struct scmi_protocol scmi_voltage = {
.id = SCMI_PROTOCOL_VOLTAGE,
.owner = THIS_MODULE,
.instance_init = &scmi_voltage_protocol_init,
.ops = &voltage_proto_ops,
.supported_version = SCMI_PROTOCOL_SUPPORTED_VERSION,
};
DEFINE_SCMI_PROTOCOL_REGISTER_UNREGISTER(voltage, scmi_voltage)