diff options
Diffstat (limited to 'drivers/firmware/arm_scmi/clock.c')
| -rw-r--r-- | drivers/firmware/arm_scmi/clock.c | 619 |
1 files changed, 619 insertions, 0 deletions
diff --git a/drivers/firmware/arm_scmi/clock.c b/drivers/firmware/arm_scmi/clock.c new file mode 100644 index 0000000000..96060bf90a --- /dev/null +++ b/drivers/firmware/arm_scmi/clock.c @@ -0,0 +1,619 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * System Control and Management Interface (SCMI) Clock Protocol + * + * Copyright (C) 2018-2022 ARM Ltd. + */ + +#include <linux/module.h> +#include <linux/limits.h> +#include <linux/sort.h> + +#include "protocols.h" +#include "notify.h" + +enum scmi_clock_protocol_cmd { + CLOCK_ATTRIBUTES = 0x3, + CLOCK_DESCRIBE_RATES = 0x4, + CLOCK_RATE_SET = 0x5, + CLOCK_RATE_GET = 0x6, + CLOCK_CONFIG_SET = 0x7, + CLOCK_NAME_GET = 0x8, + CLOCK_RATE_NOTIFY = 0x9, + CLOCK_RATE_CHANGE_REQUESTED_NOTIFY = 0xA, +}; + +struct scmi_msg_resp_clock_protocol_attributes { + __le16 num_clocks; + u8 max_async_req; + u8 reserved; +}; + +struct scmi_msg_resp_clock_attributes { + __le32 attributes; +#define CLOCK_ENABLE BIT(0) +#define SUPPORTS_RATE_CHANGED_NOTIF(x) ((x) & BIT(31)) +#define SUPPORTS_RATE_CHANGE_REQUESTED_NOTIF(x) ((x) & BIT(30)) +#define SUPPORTS_EXTENDED_NAMES(x) ((x) & BIT(29)) + u8 name[SCMI_SHORT_NAME_MAX_SIZE]; + __le32 clock_enable_latency; +}; + +struct scmi_clock_set_config { + __le32 id; + __le32 attributes; +}; + +struct scmi_msg_clock_describe_rates { + __le32 id; + __le32 rate_index; +}; + +struct scmi_msg_resp_clock_describe_rates { + __le32 num_rates_flags; +#define NUM_RETURNED(x) ((x) & 0xfff) +#define RATE_DISCRETE(x) !((x) & BIT(12)) +#define NUM_REMAINING(x) ((x) >> 16) + struct { + __le32 value_low; + __le32 value_high; + } rate[]; +#define RATE_TO_U64(X) \ +({ \ + typeof(X) x = (X); \ + le32_to_cpu((x).value_low) | (u64)le32_to_cpu((x).value_high) << 32; \ +}) +}; + +struct scmi_clock_set_rate { + __le32 flags; +#define CLOCK_SET_ASYNC BIT(0) +#define CLOCK_SET_IGNORE_RESP BIT(1) +#define CLOCK_SET_ROUND_UP BIT(2) +#define CLOCK_SET_ROUND_AUTO BIT(3) + __le32 id; + __le32 value_low; + __le32 value_high; +}; + +struct scmi_msg_resp_set_rate_complete { + __le32 id; + __le32 rate_low; + __le32 rate_high; +}; + +struct scmi_msg_clock_rate_notify { + __le32 clk_id; + __le32 notify_enable; +}; + +struct scmi_clock_rate_notify_payld { + __le32 agent_id; + __le32 clock_id; + __le32 rate_low; + __le32 rate_high; +}; + +struct clock_info { + u32 version; + int num_clocks; + int max_async_req; + atomic_t cur_async_req; + struct scmi_clock_info *clk; +}; + +static enum scmi_clock_protocol_cmd evt_2_cmd[] = { + CLOCK_RATE_NOTIFY, + CLOCK_RATE_CHANGE_REQUESTED_NOTIFY, +}; + +static int +scmi_clock_protocol_attributes_get(const struct scmi_protocol_handle *ph, + struct clock_info *ci) +{ + int ret; + struct scmi_xfer *t; + struct scmi_msg_resp_clock_protocol_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) { + ci->num_clocks = le16_to_cpu(attr->num_clocks); + ci->max_async_req = attr->max_async_req; + } + + ph->xops->xfer_put(ph, t); + return ret; +} + +static int scmi_clock_attributes_get(const struct scmi_protocol_handle *ph, + u32 clk_id, struct scmi_clock_info *clk, + u32 version) +{ + int ret; + u32 attributes; + struct scmi_xfer *t; + struct scmi_msg_resp_clock_attributes *attr; + + ret = ph->xops->xfer_get_init(ph, CLOCK_ATTRIBUTES, + sizeof(clk_id), sizeof(*attr), &t); + if (ret) + return ret; + + put_unaligned_le32(clk_id, t->tx.buf); + attr = t->rx.buf; + + ret = ph->xops->do_xfer(ph, t); + if (!ret) { + u32 latency = 0; + attributes = le32_to_cpu(attr->attributes); + strscpy(clk->name, attr->name, SCMI_SHORT_NAME_MAX_SIZE); + /* clock_enable_latency field is present only since SCMI v3.1 */ + if (PROTOCOL_REV_MAJOR(version) >= 0x2) + latency = le32_to_cpu(attr->clock_enable_latency); + clk->enable_latency = latency ? : U32_MAX; + } + + 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) >= 0x2) { + if (SUPPORTS_EXTENDED_NAMES(attributes)) + ph->hops->extended_name_get(ph, CLOCK_NAME_GET, clk_id, + clk->name, + SCMI_MAX_STR_SIZE); + + if (SUPPORTS_RATE_CHANGED_NOTIF(attributes)) + clk->rate_changed_notifications = true; + if (SUPPORTS_RATE_CHANGE_REQUESTED_NOTIF(attributes)) + clk->rate_change_requested_notifications = true; + } + + return ret; +} + +static int rate_cmp_func(const void *_r1, const void *_r2) +{ + const u64 *r1 = _r1, *r2 = _r2; + + if (*r1 < *r2) + return -1; + else if (*r1 == *r2) + return 0; + else + return 1; +} + +struct scmi_clk_ipriv { + struct device *dev; + u32 clk_id; + struct scmi_clock_info *clk; +}; + +static void iter_clk_describe_prepare_message(void *message, + const unsigned int desc_index, + const void *priv) +{ + struct scmi_msg_clock_describe_rates *msg = message; + const struct scmi_clk_ipriv *p = priv; + + msg->id = cpu_to_le32(p->clk_id); + /* Set the number of rates to be skipped/already read */ + msg->rate_index = cpu_to_le32(desc_index); +} + +static int +iter_clk_describe_update_state(struct scmi_iterator_state *st, + const void *response, void *priv) +{ + u32 flags; + struct scmi_clk_ipriv *p = priv; + const struct scmi_msg_resp_clock_describe_rates *r = response; + + flags = le32_to_cpu(r->num_rates_flags); + st->num_remaining = NUM_REMAINING(flags); + st->num_returned = NUM_RETURNED(flags); + p->clk->rate_discrete = RATE_DISCRETE(flags); + + /* Warn about out of spec replies ... */ + if (!p->clk->rate_discrete && + (st->num_returned != 3 || st->num_remaining != 0)) { + dev_warn(p->dev, + "Out-of-spec CLOCK_DESCRIBE_RATES reply for %s - returned:%d remaining:%d rx_len:%zd\n", + p->clk->name, st->num_returned, st->num_remaining, + st->rx_len); + + /* + * A known quirk: a triplet is returned but num_returned != 3 + * Check for a safe payload size and fix. + */ + if (st->num_returned != 3 && st->num_remaining == 0 && + st->rx_len == sizeof(*r) + sizeof(__le32) * 2 * 3) { + st->num_returned = 3; + st->num_remaining = 0; + } else { + dev_err(p->dev, + "Cannot fix out-of-spec reply !\n"); + return -EPROTO; + } + } + + return 0; +} + +static int +iter_clk_describe_process_response(const struct scmi_protocol_handle *ph, + const void *response, + struct scmi_iterator_state *st, void *priv) +{ + int ret = 0; + struct scmi_clk_ipriv *p = priv; + const struct scmi_msg_resp_clock_describe_rates *r = response; + + if (!p->clk->rate_discrete) { + switch (st->desc_index + st->loop_idx) { + case 0: + p->clk->range.min_rate = RATE_TO_U64(r->rate[0]); + break; + case 1: + p->clk->range.max_rate = RATE_TO_U64(r->rate[1]); + break; + case 2: + p->clk->range.step_size = RATE_TO_U64(r->rate[2]); + break; + default: + ret = -EINVAL; + break; + } + } else { + u64 *rate = &p->clk->list.rates[st->desc_index + st->loop_idx]; + + *rate = RATE_TO_U64(r->rate[st->loop_idx]); + p->clk->list.num_rates++; + } + + return ret; +} + +static int +scmi_clock_describe_rates_get(const struct scmi_protocol_handle *ph, u32 clk_id, + struct scmi_clock_info *clk) +{ + int ret; + void *iter; + struct scmi_iterator_ops ops = { + .prepare_message = iter_clk_describe_prepare_message, + .update_state = iter_clk_describe_update_state, + .process_response = iter_clk_describe_process_response, + }; + struct scmi_clk_ipriv cpriv = { + .clk_id = clk_id, + .clk = clk, + .dev = ph->dev, + }; + + iter = ph->hops->iter_response_init(ph, &ops, SCMI_MAX_NUM_RATES, + CLOCK_DESCRIBE_RATES, + sizeof(struct scmi_msg_clock_describe_rates), + &cpriv); + if (IS_ERR(iter)) + return PTR_ERR(iter); + + ret = ph->hops->iter_response_run(iter); + if (ret) + return ret; + + if (!clk->rate_discrete) { + dev_dbg(ph->dev, "Min %llu Max %llu Step %llu Hz\n", + clk->range.min_rate, clk->range.max_rate, + clk->range.step_size); + } else if (clk->list.num_rates) { + sort(clk->list.rates, clk->list.num_rates, + sizeof(clk->list.rates[0]), rate_cmp_func, NULL); + } + + return ret; +} + +static int +scmi_clock_rate_get(const struct scmi_protocol_handle *ph, + u32 clk_id, u64 *value) +{ + int ret; + struct scmi_xfer *t; + + ret = ph->xops->xfer_get_init(ph, CLOCK_RATE_GET, + sizeof(__le32), sizeof(u64), &t); + if (ret) + return ret; + + put_unaligned_le32(clk_id, t->tx.buf); + + ret = ph->xops->do_xfer(ph, t); + if (!ret) + *value = get_unaligned_le64(t->rx.buf); + + ph->xops->xfer_put(ph, t); + return ret; +} + +static int scmi_clock_rate_set(const struct scmi_protocol_handle *ph, + u32 clk_id, u64 rate) +{ + int ret; + u32 flags = 0; + struct scmi_xfer *t; + struct scmi_clock_set_rate *cfg; + struct clock_info *ci = ph->get_priv(ph); + + ret = ph->xops->xfer_get_init(ph, CLOCK_RATE_SET, sizeof(*cfg), 0, &t); + if (ret) + return ret; + + if (ci->max_async_req && + atomic_inc_return(&ci->cur_async_req) < ci->max_async_req) + flags |= CLOCK_SET_ASYNC; + + cfg = t->tx.buf; + cfg->flags = cpu_to_le32(flags); + cfg->id = cpu_to_le32(clk_id); + cfg->value_low = cpu_to_le32(rate & 0xffffffff); + cfg->value_high = cpu_to_le32(rate >> 32); + + if (flags & CLOCK_SET_ASYNC) { + ret = ph->xops->do_xfer_with_response(ph, t); + if (!ret) { + struct scmi_msg_resp_set_rate_complete *resp; + + resp = t->rx.buf; + if (le32_to_cpu(resp->id) == clk_id) + dev_dbg(ph->dev, + "Clk ID %d set async to %llu\n", clk_id, + get_unaligned_le64(&resp->rate_low)); + else + ret = -EPROTO; + } + } else { + ret = ph->xops->do_xfer(ph, t); + } + + if (ci->max_async_req) + atomic_dec(&ci->cur_async_req); + + ph->xops->xfer_put(ph, t); + return ret; +} + +static int +scmi_clock_config_set(const struct scmi_protocol_handle *ph, u32 clk_id, + u32 config, bool atomic) +{ + int ret; + struct scmi_xfer *t; + struct scmi_clock_set_config *cfg; + + ret = ph->xops->xfer_get_init(ph, CLOCK_CONFIG_SET, + sizeof(*cfg), 0, &t); + if (ret) + return ret; + + t->hdr.poll_completion = atomic; + + cfg = t->tx.buf; + cfg->id = cpu_to_le32(clk_id); + cfg->attributes = cpu_to_le32(config); + + ret = ph->xops->do_xfer(ph, t); + + ph->xops->xfer_put(ph, t); + return ret; +} + +static int scmi_clock_enable(const struct scmi_protocol_handle *ph, u32 clk_id) +{ + return scmi_clock_config_set(ph, clk_id, CLOCK_ENABLE, false); +} + +static int scmi_clock_disable(const struct scmi_protocol_handle *ph, u32 clk_id) +{ + return scmi_clock_config_set(ph, clk_id, 0, false); +} + +static int scmi_clock_enable_atomic(const struct scmi_protocol_handle *ph, + u32 clk_id) +{ + return scmi_clock_config_set(ph, clk_id, CLOCK_ENABLE, true); +} + +static int scmi_clock_disable_atomic(const struct scmi_protocol_handle *ph, + u32 clk_id) +{ + return scmi_clock_config_set(ph, clk_id, 0, true); +} + +static int scmi_clock_count_get(const struct scmi_protocol_handle *ph) +{ + struct clock_info *ci = ph->get_priv(ph); + + return ci->num_clocks; +} + +static const struct scmi_clock_info * +scmi_clock_info_get(const struct scmi_protocol_handle *ph, u32 clk_id) +{ + struct scmi_clock_info *clk; + struct clock_info *ci = ph->get_priv(ph); + + if (clk_id >= ci->num_clocks) + return NULL; + + clk = ci->clk + clk_id; + if (!clk->name[0]) + return NULL; + + return clk; +} + +static const struct scmi_clk_proto_ops clk_proto_ops = { + .count_get = scmi_clock_count_get, + .info_get = scmi_clock_info_get, + .rate_get = scmi_clock_rate_get, + .rate_set = scmi_clock_rate_set, + .enable = scmi_clock_enable, + .disable = scmi_clock_disable, + .enable_atomic = scmi_clock_enable_atomic, + .disable_atomic = scmi_clock_disable_atomic, +}; + +static int scmi_clk_rate_notify(const struct scmi_protocol_handle *ph, + u32 clk_id, int message_id, bool enable) +{ + int ret; + struct scmi_xfer *t; + struct scmi_msg_clock_rate_notify *notify; + + ret = ph->xops->xfer_get_init(ph, message_id, sizeof(*notify), 0, &t); + if (ret) + return ret; + + notify = t->tx.buf; + notify->clk_id = cpu_to_le32(clk_id); + 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_clk_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_clk_rate_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_clk_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_clock_rate_notify_payld *p = payld; + struct scmi_clock_rate_notif_report *r = report; + + if (sizeof(*p) != payld_sz || + (evt_id != SCMI_EVENT_CLOCK_RATE_CHANGED && + evt_id != SCMI_EVENT_CLOCK_RATE_CHANGE_REQUESTED)) + return NULL; + + r->timestamp = timestamp; + r->agent_id = le32_to_cpu(p->agent_id); + r->clock_id = le32_to_cpu(p->clock_id); + r->rate = get_unaligned_le64(&p->rate_low); + *src_id = r->clock_id; + + return r; +} + +static int scmi_clk_get_num_sources(const struct scmi_protocol_handle *ph) +{ + struct clock_info *ci = ph->get_priv(ph); + + if (!ci) + return -EINVAL; + + return ci->num_clocks; +} + +static const struct scmi_event clk_events[] = { + { + .id = SCMI_EVENT_CLOCK_RATE_CHANGED, + .max_payld_sz = sizeof(struct scmi_clock_rate_notify_payld), + .max_report_sz = sizeof(struct scmi_clock_rate_notif_report), + }, + { + .id = SCMI_EVENT_CLOCK_RATE_CHANGE_REQUESTED, + .max_payld_sz = sizeof(struct scmi_clock_rate_notify_payld), + .max_report_sz = sizeof(struct scmi_clock_rate_notif_report), + }, +}; + +static const struct scmi_event_ops clk_event_ops = { + .get_num_sources = scmi_clk_get_num_sources, + .set_notify_enabled = scmi_clk_set_notify_enabled, + .fill_custom_report = scmi_clk_fill_custom_report, +}; + +static const struct scmi_protocol_events clk_protocol_events = { + .queue_sz = SCMI_PROTO_QUEUE_SZ, + .ops = &clk_event_ops, + .evts = clk_events, + .num_events = ARRAY_SIZE(clk_events), +}; + +static int scmi_clock_protocol_init(const struct scmi_protocol_handle *ph) +{ + u32 version; + int clkid, ret; + struct clock_info *cinfo; + + ret = ph->xops->version_get(ph, &version); + if (ret) + return ret; + + dev_dbg(ph->dev, "Clock Version %d.%d\n", + PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version)); + + cinfo = devm_kzalloc(ph->dev, sizeof(*cinfo), GFP_KERNEL); + if (!cinfo) + return -ENOMEM; + + ret = scmi_clock_protocol_attributes_get(ph, cinfo); + if (ret) + return ret; + + cinfo->clk = devm_kcalloc(ph->dev, cinfo->num_clocks, + sizeof(*cinfo->clk), GFP_KERNEL); + if (!cinfo->clk) + return -ENOMEM; + + for (clkid = 0; clkid < cinfo->num_clocks; clkid++) { + struct scmi_clock_info *clk = cinfo->clk + clkid; + + ret = scmi_clock_attributes_get(ph, clkid, clk, version); + if (!ret) + scmi_clock_describe_rates_get(ph, clkid, clk); + } + + cinfo->version = version; + return ph->set_priv(ph, cinfo); +} + +static const struct scmi_protocol scmi_clock = { + .id = SCMI_PROTOCOL_CLOCK, + .owner = THIS_MODULE, + .instance_init = &scmi_clock_protocol_init, + .ops = &clk_proto_ops, + .events = &clk_protocol_events, +}; + +DEFINE_SCMI_PROTOCOL_REGISTER_UNREGISTER(clock, scmi_clock) |