diff options
Diffstat (limited to 'drivers/soc/qcom/rpmh.c')
| -rw-r--r-- | drivers/soc/qcom/rpmh.c | 519 |
1 files changed, 519 insertions, 0 deletions
diff --git a/drivers/soc/qcom/rpmh.c b/drivers/soc/qcom/rpmh.c new file mode 100644 index 000000000..8e19a8bdf --- /dev/null +++ b/drivers/soc/qcom/rpmh.c @@ -0,0 +1,519 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (c) 2016-2018, The Linux Foundation. All rights reserved. + */ + +#include <linux/atomic.h> +#include <linux/bug.h> +#include <linux/interrupt.h> +#include <linux/jiffies.h> +#include <linux/kernel.h> +#include <linux/list.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/slab.h> +#include <linux/spinlock.h> +#include <linux/types.h> +#include <linux/wait.h> + +#include <soc/qcom/rpmh.h> + +#include "rpmh-internal.h" + +#define RPMH_TIMEOUT_MS msecs_to_jiffies(10000) + +#define DEFINE_RPMH_MSG_ONSTACK(dev, s, q, name) \ + struct rpmh_request name = { \ + .msg = { \ + .state = s, \ + .cmds = name.cmd, \ + .num_cmds = 0, \ + .wait_for_compl = true, \ + }, \ + .cmd = { { 0 } }, \ + .completion = q, \ + .dev = dev, \ + .needs_free = false, \ + } + +#define ctrlr_to_drv(ctrlr) container_of(ctrlr, struct rsc_drv, client) + +/** + * struct cache_req: the request object for caching + * + * @addr: the address of the resource + * @sleep_val: the sleep vote + * @wake_val: the wake vote + * @list: linked list obj + */ +struct cache_req { + u32 addr; + u32 sleep_val; + u32 wake_val; + struct list_head list; +}; + +/** + * struct batch_cache_req - An entry in our batch catch + * + * @list: linked list obj + * @count: number of messages + * @rpm_msgs: the messages + */ + +struct batch_cache_req { + struct list_head list; + int count; + struct rpmh_request rpm_msgs[]; +}; + +static struct rpmh_ctrlr *get_rpmh_ctrlr(const struct device *dev) +{ + struct rsc_drv *drv = dev_get_drvdata(dev->parent); + + return &drv->client; +} + +void rpmh_tx_done(const struct tcs_request *msg, int r) +{ + struct rpmh_request *rpm_msg = container_of(msg, struct rpmh_request, + msg); + struct completion *compl = rpm_msg->completion; + bool free = rpm_msg->needs_free; + + rpm_msg->err = r; + + if (r) + dev_err(rpm_msg->dev, "RPMH TX fail in msg addr=%#x, err=%d\n", + rpm_msg->msg.cmds[0].addr, r); + + if (!compl) + goto exit; + + /* Signal the blocking thread we are done */ + complete(compl); + +exit: + if (free) + kfree(rpm_msg); +} + +static struct cache_req *__find_req(struct rpmh_ctrlr *ctrlr, u32 addr) +{ + struct cache_req *p, *req = NULL; + + list_for_each_entry(p, &ctrlr->cache, list) { + if (p->addr == addr) { + req = p; + break; + } + } + + return req; +} + +static struct cache_req *cache_rpm_request(struct rpmh_ctrlr *ctrlr, + enum rpmh_state state, + struct tcs_cmd *cmd) +{ + struct cache_req *req; + unsigned long flags; + u32 old_sleep_val, old_wake_val; + + spin_lock_irqsave(&ctrlr->cache_lock, flags); + req = __find_req(ctrlr, cmd->addr); + if (req) + goto existing; + + req = kzalloc(sizeof(*req), GFP_ATOMIC); + if (!req) { + req = ERR_PTR(-ENOMEM); + goto unlock; + } + + req->addr = cmd->addr; + req->sleep_val = req->wake_val = UINT_MAX; + list_add_tail(&req->list, &ctrlr->cache); + +existing: + old_sleep_val = req->sleep_val; + old_wake_val = req->wake_val; + + switch (state) { + case RPMH_ACTIVE_ONLY_STATE: + case RPMH_WAKE_ONLY_STATE: + req->wake_val = cmd->data; + break; + case RPMH_SLEEP_STATE: + req->sleep_val = cmd->data; + break; + } + + ctrlr->dirty |= (req->sleep_val != old_sleep_val || + req->wake_val != old_wake_val) && + req->sleep_val != UINT_MAX && + req->wake_val != UINT_MAX; + +unlock: + spin_unlock_irqrestore(&ctrlr->cache_lock, flags); + + return req; +} + +/** + * __rpmh_write: Cache and send the RPMH request + * + * @dev: The device making the request + * @state: Active/Sleep request type + * @rpm_msg: The data that needs to be sent (cmds). + * + * Cache the RPMH request and send if the state is ACTIVE_ONLY. + * SLEEP/WAKE_ONLY requests are not sent to the controller at + * this time. Use rpmh_flush() to send them to the controller. + */ +static int __rpmh_write(const struct device *dev, enum rpmh_state state, + struct rpmh_request *rpm_msg) +{ + struct rpmh_ctrlr *ctrlr = get_rpmh_ctrlr(dev); + int ret = -EINVAL; + struct cache_req *req; + int i; + + rpm_msg->msg.state = state; + + /* Cache the request in our store and link the payload */ + for (i = 0; i < rpm_msg->msg.num_cmds; i++) { + req = cache_rpm_request(ctrlr, state, &rpm_msg->msg.cmds[i]); + if (IS_ERR(req)) + return PTR_ERR(req); + } + + rpm_msg->msg.state = state; + + if (state == RPMH_ACTIVE_ONLY_STATE) { + WARN_ON(irqs_disabled()); + ret = rpmh_rsc_send_data(ctrlr_to_drv(ctrlr), &rpm_msg->msg); + } else { + ret = rpmh_rsc_write_ctrl_data(ctrlr_to_drv(ctrlr), + &rpm_msg->msg); + /* Clean up our call by spoofing tx_done */ + rpmh_tx_done(&rpm_msg->msg, ret); + } + + return ret; +} + +static int __fill_rpmh_msg(struct rpmh_request *req, enum rpmh_state state, + const struct tcs_cmd *cmd, u32 n) +{ + if (!cmd || !n || n > MAX_RPMH_PAYLOAD) + return -EINVAL; + + memcpy(req->cmd, cmd, n * sizeof(*cmd)); + + req->msg.state = state; + req->msg.cmds = req->cmd; + req->msg.num_cmds = n; + + return 0; +} + +/** + * rpmh_write_async: Write a set of RPMH commands + * + * @dev: The device making the request + * @state: Active/sleep set + * @cmd: The payload data + * @n: The number of elements in payload + * + * Write a set of RPMH commands, the order of commands is maintained + * and will be sent as a single shot. + */ +int rpmh_write_async(const struct device *dev, enum rpmh_state state, + const struct tcs_cmd *cmd, u32 n) +{ + struct rpmh_request *rpm_msg; + int ret; + + rpm_msg = kzalloc(sizeof(*rpm_msg), GFP_ATOMIC); + if (!rpm_msg) + return -ENOMEM; + rpm_msg->needs_free = true; + + ret = __fill_rpmh_msg(rpm_msg, state, cmd, n); + if (ret) { + kfree(rpm_msg); + return ret; + } + + return __rpmh_write(dev, state, rpm_msg); +} +EXPORT_SYMBOL(rpmh_write_async); + +/** + * rpmh_write: Write a set of RPMH commands and block until response + * + * @rc: The RPMH handle got from rpmh_get_client + * @state: Active/sleep set + * @cmd: The payload data + * @n: The number of elements in @cmd + * + * May sleep. Do not call from atomic contexts. + */ +int rpmh_write(const struct device *dev, enum rpmh_state state, + const struct tcs_cmd *cmd, u32 n) +{ + DECLARE_COMPLETION_ONSTACK(compl); + DEFINE_RPMH_MSG_ONSTACK(dev, state, &compl, rpm_msg); + int ret; + + if (!cmd || !n || n > MAX_RPMH_PAYLOAD) + return -EINVAL; + + memcpy(rpm_msg.cmd, cmd, n * sizeof(*cmd)); + rpm_msg.msg.num_cmds = n; + + ret = __rpmh_write(dev, state, &rpm_msg); + if (ret) + return ret; + + ret = wait_for_completion_timeout(&compl, RPMH_TIMEOUT_MS); + WARN_ON(!ret); + return (ret > 0) ? 0 : -ETIMEDOUT; +} +EXPORT_SYMBOL(rpmh_write); + +static void cache_batch(struct rpmh_ctrlr *ctrlr, struct batch_cache_req *req) +{ + unsigned long flags; + + spin_lock_irqsave(&ctrlr->cache_lock, flags); + list_add_tail(&req->list, &ctrlr->batch_cache); + ctrlr->dirty = true; + spin_unlock_irqrestore(&ctrlr->cache_lock, flags); +} + +static int flush_batch(struct rpmh_ctrlr *ctrlr) +{ + struct batch_cache_req *req; + const struct rpmh_request *rpm_msg; + unsigned long flags; + int ret = 0; + int i; + + /* Send Sleep/Wake requests to the controller, expect no response */ + spin_lock_irqsave(&ctrlr->cache_lock, flags); + list_for_each_entry(req, &ctrlr->batch_cache, list) { + for (i = 0; i < req->count; i++) { + rpm_msg = req->rpm_msgs + i; + ret = rpmh_rsc_write_ctrl_data(ctrlr_to_drv(ctrlr), + &rpm_msg->msg); + if (ret) + break; + } + } + spin_unlock_irqrestore(&ctrlr->cache_lock, flags); + + return ret; +} + +/** + * rpmh_write_batch: Write multiple sets of RPMH commands and wait for the + * batch to finish. + * + * @dev: the device making the request + * @state: Active/sleep set + * @cmd: The payload data + * @n: The array of count of elements in each batch, 0 terminated. + * + * Write a request to the RSC controller without caching. If the request + * state is ACTIVE, then the requests are treated as completion request + * and sent to the controller immediately. The function waits until all the + * commands are complete. If the request was to SLEEP or WAKE_ONLY, then the + * request is sent as fire-n-forget and no ack is expected. + * + * May sleep. Do not call from atomic contexts for ACTIVE_ONLY requests. + */ +int rpmh_write_batch(const struct device *dev, enum rpmh_state state, + const struct tcs_cmd *cmd, u32 *n) +{ + struct batch_cache_req *req; + struct rpmh_request *rpm_msgs; + struct completion *compls; + struct rpmh_ctrlr *ctrlr = get_rpmh_ctrlr(dev); + unsigned long time_left; + int count = 0; + int ret, i; + void *ptr; + + if (!cmd || !n) + return -EINVAL; + + while (n[count] > 0) + count++; + if (!count) + return -EINVAL; + + ptr = kzalloc(sizeof(*req) + + count * (sizeof(req->rpm_msgs[0]) + sizeof(*compls)), + GFP_ATOMIC); + if (!ptr) + return -ENOMEM; + + req = ptr; + compls = ptr + sizeof(*req) + count * sizeof(*rpm_msgs); + + req->count = count; + rpm_msgs = req->rpm_msgs; + + for (i = 0; i < count; i++) { + __fill_rpmh_msg(rpm_msgs + i, state, cmd, n[i]); + cmd += n[i]; + } + + if (state != RPMH_ACTIVE_ONLY_STATE) { + cache_batch(ctrlr, req); + return 0; + } + + for (i = 0; i < count; i++) { + struct completion *compl = &compls[i]; + + init_completion(compl); + rpm_msgs[i].completion = compl; + ret = rpmh_rsc_send_data(ctrlr_to_drv(ctrlr), &rpm_msgs[i].msg); + if (ret) { + pr_err("Error(%d) sending RPMH message addr=%#x\n", + ret, rpm_msgs[i].msg.cmds[0].addr); + break; + } + } + + time_left = RPMH_TIMEOUT_MS; + while (i--) { + time_left = wait_for_completion_timeout(&compls[i], time_left); + if (!time_left) { + /* + * Better hope they never finish because they'll signal + * the completion that we're going to free once + * we've returned from this function. + */ + WARN_ON(1); + ret = -ETIMEDOUT; + goto exit; + } + } + +exit: + kfree(ptr); + + return ret; +} +EXPORT_SYMBOL(rpmh_write_batch); + +static int is_req_valid(struct cache_req *req) +{ + return (req->sleep_val != UINT_MAX && + req->wake_val != UINT_MAX && + req->sleep_val != req->wake_val); +} + +static int send_single(const struct device *dev, enum rpmh_state state, + u32 addr, u32 data) +{ + DEFINE_RPMH_MSG_ONSTACK(dev, state, NULL, rpm_msg); + struct rpmh_ctrlr *ctrlr = get_rpmh_ctrlr(dev); + + /* Wake sets are always complete and sleep sets are not */ + rpm_msg.msg.wait_for_compl = (state == RPMH_WAKE_ONLY_STATE); + rpm_msg.cmd[0].addr = addr; + rpm_msg.cmd[0].data = data; + rpm_msg.msg.num_cmds = 1; + + return rpmh_rsc_write_ctrl_data(ctrlr_to_drv(ctrlr), &rpm_msg.msg); +} + +/** + * rpmh_flush: Flushes the buffered active and sleep sets to TCS + * + * @dev: The device making the request + * + * Return: -EBUSY if the controller is busy, probably waiting on a response + * to a RPMH request sent earlier. + * + * This function is always called from the sleep code from the last CPU + * that is powering down the entire system. Since no other RPMH API would be + * executing at this time, it is safe to run lockless. + */ +int rpmh_flush(const struct device *dev) +{ + struct cache_req *p; + struct rpmh_ctrlr *ctrlr = get_rpmh_ctrlr(dev); + int ret; + + if (!ctrlr->dirty) { + pr_debug("Skipping flush, TCS has latest data.\n"); + return 0; + } + + /* Invalidate the TCSes first to avoid stale data */ + do { + ret = rpmh_rsc_invalidate(ctrlr_to_drv(ctrlr)); + } while (ret == -EAGAIN); + if (ret) + return ret; + + /* First flush the cached batch requests */ + ret = flush_batch(ctrlr); + if (ret) + return ret; + + /* + * Nobody else should be calling this function other than system PM, + * hence we can run without locks. + */ + list_for_each_entry(p, &ctrlr->cache, list) { + if (!is_req_valid(p)) { + pr_debug("%s: skipping RPMH req: a:%#x s:%#x w:%#x", + __func__, p->addr, p->sleep_val, p->wake_val); + continue; + } + ret = send_single(dev, RPMH_SLEEP_STATE, p->addr, p->sleep_val); + if (ret) + return ret; + ret = send_single(dev, RPMH_WAKE_ONLY_STATE, + p->addr, p->wake_val); + if (ret) + return ret; + } + + ctrlr->dirty = false; + + return 0; +} +EXPORT_SYMBOL(rpmh_flush); + +/** + * rpmh_invalidate: Invalidate sleep and wake sets in batch_cache + * + * @dev: The device making the request + * + * Invalidate the sleep and wake values in batch_cache. + */ +int rpmh_invalidate(const struct device *dev) +{ + struct rpmh_ctrlr *ctrlr = get_rpmh_ctrlr(dev); + struct batch_cache_req *req, *tmp; + unsigned long flags; + + spin_lock_irqsave(&ctrlr->cache_lock, flags); + list_for_each_entry_safe(req, tmp, &ctrlr->batch_cache, list) + kfree(req); + INIT_LIST_HEAD(&ctrlr->batch_cache); + ctrlr->dirty = true; + spin_unlock_irqrestore(&ctrlr->cache_lock, flags); + + return 0; +} +EXPORT_SYMBOL(rpmh_invalidate); |