diff --git a/drivers/firmware/arm_scmi/Makefile b/drivers/firmware/arm_scmi/Makefile index 687cbbfb3af6..2130ee9ac825 100644 --- a/drivers/firmware/arm_scmi/Makefile +++ b/drivers/firmware/arm_scmi/Makefile @@ -1,4 +1,4 @@ obj-y = scmi-bus.o scmi-driver.o scmi-protocols.o scmi-bus-y = bus.o scmi-driver-y = driver.o -scmi-protocols-y = base.o perf.o +scmi-protocols-y = base.o clock.o perf.o diff --git a/drivers/firmware/arm_scmi/clock.c b/drivers/firmware/arm_scmi/clock.c new file mode 100644 index 000000000000..e8ffad33a0ff --- /dev/null +++ b/drivers/firmware/arm_scmi/clock.c @@ -0,0 +1,342 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * System Control and Management Interface (SCMI) Clock Protocol + * + * Copyright (C) 2018 ARM Ltd. + */ + +#include "common.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, +}; + +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) + u8 name[SCMI_MAX_STR_SIZE]; +}; + +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[0]; +#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_DELAYED 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 clock_info { + int num_clocks; + int max_async_req; + struct scmi_clock_info *clk; +}; + +static int scmi_clock_protocol_attributes_get(const struct scmi_handle *handle, + struct clock_info *ci) +{ + int ret; + struct scmi_xfer *t; + struct scmi_msg_resp_clock_protocol_attributes *attr; + + ret = scmi_one_xfer_init(handle, PROTOCOL_ATTRIBUTES, + SCMI_PROTOCOL_CLOCK, 0, sizeof(*attr), &t); + if (ret) + return ret; + + attr = t->rx.buf; + + ret = scmi_do_xfer(handle, t); + if (!ret) { + ci->num_clocks = le16_to_cpu(attr->num_clocks); + ci->max_async_req = attr->max_async_req; + } + + scmi_one_xfer_put(handle, t); + return ret; +} + +static int scmi_clock_attributes_get(const struct scmi_handle *handle, + u32 clk_id, struct scmi_clock_info *clk) +{ + int ret; + struct scmi_xfer *t; + struct scmi_msg_resp_clock_attributes *attr; + + ret = scmi_one_xfer_init(handle, CLOCK_ATTRIBUTES, SCMI_PROTOCOL_CLOCK, + sizeof(clk_id), sizeof(*attr), &t); + if (ret) + return ret; + + *(__le32 *)t->tx.buf = cpu_to_le32(clk_id); + attr = t->rx.buf; + + ret = scmi_do_xfer(handle, t); + if (!ret) + memcpy(clk->name, attr->name, SCMI_MAX_STR_SIZE); + else + clk->name[0] = '\0'; + + scmi_one_xfer_put(handle, t); + return ret; +} + +static int +scmi_clock_describe_rates_get(const struct scmi_handle *handle, u32 clk_id, + struct scmi_clock_info *clk) +{ + u64 *rate; + int ret, cnt; + bool rate_discrete; + u32 tot_rate_cnt = 0, rates_flag; + u16 num_returned, num_remaining; + struct scmi_xfer *t; + struct scmi_msg_clock_describe_rates *clk_desc; + struct scmi_msg_resp_clock_describe_rates *rlist; + + ret = scmi_one_xfer_init(handle, CLOCK_DESCRIBE_RATES, + SCMI_PROTOCOL_CLOCK, sizeof(*clk_desc), 0, &t); + if (ret) + return ret; + + clk_desc = t->tx.buf; + rlist = t->rx.buf; + + do { + clk_desc->id = cpu_to_le32(clk_id); + /* Set the number of rates to be skipped/already read */ + clk_desc->rate_index = cpu_to_le32(tot_rate_cnt); + + ret = scmi_do_xfer(handle, t); + if (ret) + break; + + rates_flag = le32_to_cpu(rlist->num_rates_flags); + num_remaining = NUM_REMAINING(rates_flag); + rate_discrete = RATE_DISCRETE(rates_flag); + num_returned = NUM_RETURNED(rates_flag); + + if (tot_rate_cnt + num_returned > SCMI_MAX_NUM_RATES) { + dev_err(handle->dev, "No. of rates > MAX_NUM_RATES"); + break; + } + + if (!rate_discrete) { + clk->range.min_rate = RATE_TO_U64(rlist->rate[0]); + clk->range.max_rate = RATE_TO_U64(rlist->rate[1]); + clk->range.step_size = RATE_TO_U64(rlist->rate[2]); + dev_dbg(handle->dev, "Min %llu Max %llu Step %llu Hz\n", + clk->range.min_rate, clk->range.max_rate, + clk->range.step_size); + break; + } + + rate = &clk->list.rates[tot_rate_cnt]; + for (cnt = 0; cnt < num_returned; cnt++, rate++) { + *rate = RATE_TO_U64(rlist->rate[cnt]); + dev_dbg(handle->dev, "Rate %llu Hz\n", *rate); + } + + tot_rate_cnt += num_returned; + /* + * check for both returned and remaining to avoid infinite + * loop due to buggy firmware + */ + } while (num_returned && num_remaining); + + if (rate_discrete) + clk->list.num_rates = tot_rate_cnt; + + scmi_one_xfer_put(handle, t); + return ret; +} + +static int +scmi_clock_rate_get(const struct scmi_handle *handle, u32 clk_id, u64 *value) +{ + int ret; + struct scmi_xfer *t; + + ret = scmi_one_xfer_init(handle, CLOCK_RATE_GET, SCMI_PROTOCOL_CLOCK, + sizeof(__le32), sizeof(u64), &t); + if (ret) + return ret; + + *(__le32 *)t->tx.buf = cpu_to_le32(clk_id); + + ret = scmi_do_xfer(handle, t); + if (!ret) { + __le32 *pval = t->rx.buf; + + *value = le32_to_cpu(*pval); + *value |= (u64)le32_to_cpu(*(pval + 1)) << 32; + } + + scmi_one_xfer_put(handle, t); + return ret; +} + +static int scmi_clock_rate_set(const struct scmi_handle *handle, u32 clk_id, + u32 config, u64 rate) +{ + int ret; + struct scmi_xfer *t; + struct scmi_clock_set_rate *cfg; + + ret = scmi_one_xfer_init(handle, CLOCK_RATE_SET, SCMI_PROTOCOL_CLOCK, + sizeof(*cfg), 0, &t); + if (ret) + return ret; + + cfg = t->tx.buf; + cfg->flags = cpu_to_le32(config); + cfg->id = cpu_to_le32(clk_id); + cfg->value_low = cpu_to_le32(rate & 0xffffffff); + cfg->value_high = cpu_to_le32(rate >> 32); + + ret = scmi_do_xfer(handle, t); + + scmi_one_xfer_put(handle, t); + return ret; +} + +static int +scmi_clock_config_set(const struct scmi_handle *handle, u32 clk_id, u32 config) +{ + int ret; + struct scmi_xfer *t; + struct scmi_clock_set_config *cfg; + + ret = scmi_one_xfer_init(handle, CLOCK_CONFIG_SET, SCMI_PROTOCOL_CLOCK, + sizeof(*cfg), 0, &t); + if (ret) + return ret; + + cfg = t->tx.buf; + cfg->id = cpu_to_le32(clk_id); + cfg->attributes = cpu_to_le32(config); + + ret = scmi_do_xfer(handle, t); + + scmi_one_xfer_put(handle, t); + return ret; +} + +static int scmi_clock_enable(const struct scmi_handle *handle, u32 clk_id) +{ + return scmi_clock_config_set(handle, clk_id, CLOCK_ENABLE); +} + +static int scmi_clock_disable(const struct scmi_handle *handle, u32 clk_id) +{ + return scmi_clock_config_set(handle, clk_id, 0); +} + +static int scmi_clock_count_get(const struct scmi_handle *handle) +{ + struct clock_info *ci = handle->clk_priv; + + return ci->num_clocks; +} + +static const struct scmi_clock_info * +scmi_clock_info_get(const struct scmi_handle *handle, u32 clk_id) +{ + struct clock_info *ci = handle->clk_priv; + struct scmi_clock_info *clk = ci->clk + clk_id; + + if (!clk->name || !clk->name[0]) + return NULL; + + return clk; +} + +static struct scmi_clk_ops clk_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, +}; + +static int scmi_clock_protocol_init(struct scmi_handle *handle) +{ + u32 version; + int clkid, ret; + struct clock_info *cinfo; + + scmi_version_get(handle, SCMI_PROTOCOL_CLOCK, &version); + + dev_dbg(handle->dev, "Clock Version %d.%d\n", + PROTOCOL_REV_MAJOR(version), PROTOCOL_REV_MINOR(version)); + + cinfo = devm_kzalloc(handle->dev, sizeof(*cinfo), GFP_KERNEL); + if (!cinfo) + return -ENOMEM; + + scmi_clock_protocol_attributes_get(handle, cinfo); + + cinfo->clk = devm_kcalloc(handle->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(handle, clkid, clk); + if (!ret) + scmi_clock_describe_rates_get(handle, clkid, clk); + } + + handle->clk_ops = &clk_ops; + handle->clk_priv = cinfo; + + return 0; +} + +static int __init scmi_clock_init(void) +{ + return scmi_protocol_register(SCMI_PROTOCOL_CLOCK, + &scmi_clock_protocol_init); +} +subsys_initcall(scmi_clock_init); diff --git a/include/linux/scmi_protocol.h b/include/linux/scmi_protocol.h index 57d4b1c099e5..5a3092f05011 100644 --- a/include/linux/scmi_protocol.h +++ b/include/linux/scmi_protocol.h @@ -8,6 +8,7 @@ #include #define SCMI_MAX_STR_SIZE 16 +#define SCMI_MAX_NUM_RATES 16 /** * struct scmi_revision_info - version information structure @@ -33,8 +34,48 @@ struct scmi_revision_info { char sub_vendor_id[SCMI_MAX_STR_SIZE]; }; +struct scmi_clock_info { + char name[SCMI_MAX_STR_SIZE]; + bool rate_discrete; + union { + struct { + int num_rates; + u64 rates[SCMI_MAX_NUM_RATES]; + } list; + struct { + u64 min_rate; + u64 max_rate; + u64 step_size; + } range; + }; +}; + struct scmi_handle; +/** + * struct scmi_clk_ops - represents the various operations provided + * by SCMI Clock Protocol + * + * @count_get: get the count of clocks provided by SCMI + * @info_get: get the information of the specified clock + * @rate_get: request the current clock rate of a clock + * @rate_set: set the clock rate of a clock + * @enable: enables the specified clock + * @disable: disables the specified clock + */ +struct scmi_clk_ops { + int (*count_get)(const struct scmi_handle *handle); + + const struct scmi_clock_info *(*info_get) + (const struct scmi_handle *handle, u32 clk_id); + int (*rate_get)(const struct scmi_handle *handle, u32 clk_id, + u64 *rate); + int (*rate_set)(const struct scmi_handle *handle, u32 clk_id, + u32 config, u64 rate); + int (*enable)(const struct scmi_handle *handle, u32 clk_id); + int (*disable)(const struct scmi_handle *handle, u32 clk_id); +}; + /** * struct scmi_perf_ops - represents the various operations provided * by SCMI Performance Protocol @@ -77,13 +118,16 @@ struct scmi_perf_ops { * @dev: pointer to the SCMI device * @version: pointer to the structure containing SCMI version information * @perf_ops: pointer to set of performance protocol operations + * @clk_ops: pointer to set of clock protocol operations */ struct scmi_handle { struct device *dev; struct scmi_revision_info *version; struct scmi_perf_ops *perf_ops; + struct scmi_clk_ops *clk_ops; /* for protocol internal use */ void *perf_priv; + void *clk_priv; }; enum scmi_std_protocol {