diff --git a/drivers/soc/qcom/rpmh-internal.h b/drivers/soc/qcom/rpmh-internal.h index ef60e790a750..344ba687c13b 100644 --- a/drivers/soc/qcom/rpmh-internal.h +++ b/drivers/soc/qcom/rpmh-internal.h @@ -8,6 +8,7 @@ #define __RPM_INTERNAL_H__ #include +#include #include #define TCS_TYPE_NR 4 @@ -106,6 +107,8 @@ struct rpmh_ctrlr { * @lock: Synchronize state of the controller. If RPMH's cache * lock will also be held, the order is: drv->lock then * cache_lock. + * @tcs_wait: Wait queue used to wait for @tcs_in_use to free up a + * slot * @client: Handle to the DRV's client. */ struct rsc_drv { @@ -118,6 +121,7 @@ struct rsc_drv { struct tcs_group tcs[TCS_TYPE_NR]; DECLARE_BITMAP(tcs_in_use, MAX_TCS_NR); spinlock_t lock; + wait_queue_head_t tcs_wait; struct rpmh_ctrlr client; }; diff --git a/drivers/soc/qcom/rpmh-rsc.c b/drivers/soc/qcom/rpmh-rsc.c index ae6675782581..a297911afe57 100644 --- a/drivers/soc/qcom/rpmh-rsc.c +++ b/drivers/soc/qcom/rpmh-rsc.c @@ -19,6 +19,7 @@ #include #include #include +#include #include #include @@ -453,6 +454,7 @@ skip: if (!drv->tcs[ACTIVE_TCS].num_tcs) enable_tcs_irq(drv, i, false); spin_unlock(&drv->lock); + wake_up(&drv->tcs_wait); if (req) rpmh_tx_done(req, err); } @@ -571,43 +573,74 @@ static int find_free_tcs(struct tcs_group *tcs) } /** - * tcs_write() - Store messages into a TCS right now, or return -EBUSY. + * claim_tcs_for_req() - Claim a tcs in the given tcs_group; only for active. * @drv: The controller. + * @tcs: The tcs_group used for ACTIVE_ONLY transfers. * @msg: The data to be sent. * - * Grabs a TCS for ACTIVE_ONLY transfers and writes the messages to it. + * Claims a tcs in the given tcs_group while making sure that no existing cmd + * is in flight that would conflict with the one in @msg. * - * If there are no free TCSes for ACTIVE_ONLY transfers or if a command for - * the same address is already transferring returns -EBUSY which means the - * client should retry shortly. + * Context: Must be called with the drv->lock held since that protects + * tcs_in_use. * - * Return: 0 on success, -EBUSY if client should retry, or an error. - * Client should have interrupts enabled for a bit before retrying. + * Return: The id of the claimed tcs or -EBUSY if a matching msg is in flight + * or the tcs_group is full. */ -static int tcs_write(struct rsc_drv *drv, const struct tcs_request *msg) +static int claim_tcs_for_req(struct rsc_drv *drv, struct tcs_group *tcs, + const struct tcs_request *msg) { - struct tcs_group *tcs; - int tcs_id; - unsigned long flags; int ret; - tcs = get_tcs_for_msg(drv, msg); - if (IS_ERR(tcs)) - return PTR_ERR(tcs); - - spin_lock_irqsave(&drv->lock, flags); /* * The h/w does not like if we send a request to the same address, * when one is already in-flight or being processed. */ ret = check_for_req_inflight(drv, tcs, msg); if (ret) - goto unlock; + return ret; - ret = find_free_tcs(tcs); - if (ret < 0) - goto unlock; - tcs_id = ret; + return find_free_tcs(tcs); +} + +/** + * rpmh_rsc_send_data() - Write / trigger active-only message. + * @drv: The controller. + * @msg: The data to be sent. + * + * NOTES: + * - This is only used for "ACTIVE_ONLY" since the limitations of this + * function don't make sense for sleep/wake cases. + * - To do the transfer, we will grab a whole TCS for ourselves--we don't + * try to share. If there are none available we'll wait indefinitely + * for a free one. + * - This function will not wait for the commands to be finished, only for + * data to be programmed into the RPMh. See rpmh_tx_done() which will + * be called when the transfer is fully complete. + * - This function must be called with interrupts enabled. If the hardware + * is busy doing someone else's transfer we need that transfer to fully + * finish so that we can have the hardware, and to fully finish it needs + * the interrupt handler to run. If the interrupts is set to run on the + * active CPU this can never happen if interrupts are disabled. + * + * Return: 0 on success, -EINVAL on error. + */ +int rpmh_rsc_send_data(struct rsc_drv *drv, const struct tcs_request *msg) +{ + struct tcs_group *tcs; + int tcs_id; + unsigned long flags; + + tcs = get_tcs_for_msg(drv, msg); + if (IS_ERR(tcs)) + return PTR_ERR(tcs); + + spin_lock_irqsave(&drv->lock, flags); + + /* Wait forever for a free tcs. It better be there eventually! */ + wait_event_lock_irq(drv->tcs_wait, + (tcs_id = claim_tcs_for_req(drv, tcs, msg)) >= 0, + drv->lock); tcs->req[tcs_id - tcs->offset] = msg; set_bit(tcs_id, drv->tcs_in_use); @@ -635,47 +668,6 @@ static int tcs_write(struct rsc_drv *drv, const struct tcs_request *msg) __tcs_set_trigger(drv, tcs_id, true); return 0; -unlock: - spin_unlock_irqrestore(&drv->lock, flags); - return ret; -} - -/** - * rpmh_rsc_send_data() - Write / trigger active-only message. - * @drv: The controller. - * @msg: The data to be sent. - * - * NOTES: - * - This is only used for "ACTIVE_ONLY" since the limitations of this - * function don't make sense for sleep/wake cases. - * - To do the transfer, we will grab a whole TCS for ourselves--we don't - * try to share. If there are none available we'll wait indefinitely - * for a free one. - * - This function will not wait for the commands to be finished, only for - * data to be programmed into the RPMh. See rpmh_tx_done() which will - * be called when the transfer is fully complete. - * - This function must be called with interrupts enabled. If the hardware - * is busy doing someone else's transfer we need that transfer to fully - * finish so that we can have the hardware, and to fully finish it needs - * the interrupt handler to run. If the interrupts is set to run on the - * active CPU this can never happen if interrupts are disabled. - * - * Return: 0 on success, -EINVAL on error. - */ -int rpmh_rsc_send_data(struct rsc_drv *drv, const struct tcs_request *msg) -{ - int ret; - - do { - ret = tcs_write(drv, msg); - if (ret == -EBUSY) { - pr_info_ratelimited("TCS Busy, retrying RPMH message send: addr=%#x\n", - msg->cmds[0].addr); - udelay(10); - } - } while (ret == -EBUSY); - - return ret; } /** @@ -983,6 +975,7 @@ static int rpmh_rsc_probe(struct platform_device *pdev) return ret; spin_lock_init(&drv->lock); + init_waitqueue_head(&drv->tcs_wait); bitmap_zero(drv->tcs_in_use, MAX_TCS_NR); irq = platform_get_irq(pdev, drv->id);