#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>
#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;
+};
+
static struct rpmh_ctrlr *get_rpmh_ctrlr(const struct device *dev)
{
struct rsc_drv *drv = dev_get_drvdata(dev->parent);
complete(compl);
}
+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;
+
+ 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;
+ INIT_LIST_HEAD(&req->list);
+ list_add_tail(&req->list, &ctrlr->cache);
+
+existing:
+ switch (state) {
+ case RPMH_ACTIVE_ONLY_STATE:
+ if (req->sleep_val != UINT_MAX)
+ req->wake_val = cmd->data;
+ break;
+ case RPMH_WAKE_ONLY_STATE:
+ req->wake_val = cmd->data;
+ break;
+ case RPMH_SLEEP_STATE:
+ req->sleep_val = cmd->data;
+ break;
+ default:
+ break;
+ }
+
+ ctrlr->dirty = true;
+unlock:
+ spin_unlock_irqrestore(&ctrlr->cache_lock, flags);
+
+ return req;
+}
+
/**
- * __rpmh_write: send the RPMH request
+ * __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;
- if (state != RPMH_ACTIVE_ONLY_STATE)
- return -EINVAL;
+ /* 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;
- WARN_ON(irqs_disabled());
+ 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 rpmh_rsc_send_data(ctrlr_to_drv(ctrlr), &rpm_msg->msg);
+ return ret;
}
/**
return (ret > 0) ? 0 : -ETIMEDOUT;
}
EXPORT_SYMBOL(rpmh_write);
+
+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;
+ }
+
+ /*
+ * 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 all sleep and active sets
+ * sets.
+ *
+ * @dev: The device making the request
+ *
+ * Invalidate the sleep and active values in the TCS blocks.
+ */
+int rpmh_invalidate(const struct device *dev)
+{
+ struct rpmh_ctrlr *ctrlr = get_rpmh_ctrlr(dev);
+ int ret;
+
+ ctrlr->dirty = true;
+
+ do {
+ ret = rpmh_rsc_invalidate(ctrlr_to_drv(ctrlr));
+ } while (ret == -EAGAIN);
+
+ return ret;
+}
+EXPORT_SYMBOL(rpmh_invalidate);
projects / platform / kernel / linux-rpi.git / commitdiff