diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /drivers/mmc/host/mmc_hsq.c | |
parent | Initial commit. (diff) | |
download | linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip |
Adding upstream version 5.10.209.upstream/5.10.209
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/mmc/host/mmc_hsq.c')
-rw-r--r-- | drivers/mmc/host/mmc_hsq.c | 375 |
1 files changed, 375 insertions, 0 deletions
diff --git a/drivers/mmc/host/mmc_hsq.c b/drivers/mmc/host/mmc_hsq.c new file mode 100644 index 000000000..9d35453e7 --- /dev/null +++ b/drivers/mmc/host/mmc_hsq.c @@ -0,0 +1,375 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * + * MMC software queue support based on command queue interfaces + * + * Copyright (C) 2019 Linaro, Inc. + * Author: Baolin Wang <baolin.wang@linaro.org> + */ + +#include <linux/mmc/card.h> +#include <linux/mmc/host.h> +#include <linux/module.h> + +#include "mmc_hsq.h" + +#define HSQ_NUM_SLOTS 64 +#define HSQ_INVALID_TAG HSQ_NUM_SLOTS + +static void mmc_hsq_retry_handler(struct work_struct *work) +{ + struct mmc_hsq *hsq = container_of(work, struct mmc_hsq, retry_work); + struct mmc_host *mmc = hsq->mmc; + + mmc->ops->request(mmc, hsq->mrq); +} + +static void mmc_hsq_pump_requests(struct mmc_hsq *hsq) +{ + struct mmc_host *mmc = hsq->mmc; + struct hsq_slot *slot; + unsigned long flags; + int ret = 0; + + spin_lock_irqsave(&hsq->lock, flags); + + /* Make sure we are not already running a request now */ + if (hsq->mrq || hsq->recovery_halt) { + spin_unlock_irqrestore(&hsq->lock, flags); + return; + } + + /* Make sure there are remain requests need to pump */ + if (!hsq->qcnt || !hsq->enabled) { + spin_unlock_irqrestore(&hsq->lock, flags); + return; + } + + slot = &hsq->slot[hsq->next_tag]; + hsq->mrq = slot->mrq; + hsq->qcnt--; + + spin_unlock_irqrestore(&hsq->lock, flags); + + if (mmc->ops->request_atomic) + ret = mmc->ops->request_atomic(mmc, hsq->mrq); + else + mmc->ops->request(mmc, hsq->mrq); + + /* + * If returning BUSY from request_atomic(), which means the card + * may be busy now, and we should change to non-atomic context to + * try again for this unusual case, to avoid time-consuming operations + * in the atomic context. + * + * Note: we just give a warning for other error cases, since the host + * driver will handle them. + */ + if (ret == -EBUSY) + schedule_work(&hsq->retry_work); + else + WARN_ON_ONCE(ret); +} + +static void mmc_hsq_update_next_tag(struct mmc_hsq *hsq, int remains) +{ + struct hsq_slot *slot; + int tag; + + /* + * If there are no remain requests in software queue, then set a invalid + * tag. + */ + if (!remains) { + hsq->next_tag = HSQ_INVALID_TAG; + return; + } + + /* + * Increasing the next tag and check if the corresponding request is + * available, if yes, then we found a candidate request. + */ + if (++hsq->next_tag != HSQ_INVALID_TAG) { + slot = &hsq->slot[hsq->next_tag]; + if (slot->mrq) + return; + } + + /* Othersie we should iterate all slots to find a available tag. */ + for (tag = 0; tag < HSQ_NUM_SLOTS; tag++) { + slot = &hsq->slot[tag]; + if (slot->mrq) + break; + } + + if (tag == HSQ_NUM_SLOTS) + tag = HSQ_INVALID_TAG; + + hsq->next_tag = tag; +} + +static void mmc_hsq_post_request(struct mmc_hsq *hsq) +{ + unsigned long flags; + int remains; + + spin_lock_irqsave(&hsq->lock, flags); + + remains = hsq->qcnt; + hsq->mrq = NULL; + + /* Update the next available tag to be queued. */ + mmc_hsq_update_next_tag(hsq, remains); + + if (hsq->waiting_for_idle && !remains) { + hsq->waiting_for_idle = false; + wake_up(&hsq->wait_queue); + } + + /* Do not pump new request in recovery mode. */ + if (hsq->recovery_halt) { + spin_unlock_irqrestore(&hsq->lock, flags); + return; + } + + spin_unlock_irqrestore(&hsq->lock, flags); + + /* + * Try to pump new request to host controller as fast as possible, + * after completing previous request. + */ + if (remains > 0) + mmc_hsq_pump_requests(hsq); +} + +/** + * mmc_hsq_finalize_request - finalize one request if the request is done + * @mmc: the host controller + * @mrq: the request need to be finalized + * + * Return true if we finalized the corresponding request in software queue, + * otherwise return false. + */ +bool mmc_hsq_finalize_request(struct mmc_host *mmc, struct mmc_request *mrq) +{ + struct mmc_hsq *hsq = mmc->cqe_private; + unsigned long flags; + + spin_lock_irqsave(&hsq->lock, flags); + + if (!hsq->enabled || !hsq->mrq || hsq->mrq != mrq) { + spin_unlock_irqrestore(&hsq->lock, flags); + return false; + } + + /* + * Clear current completed slot request to make a room for new request. + */ + hsq->slot[hsq->next_tag].mrq = NULL; + + spin_unlock_irqrestore(&hsq->lock, flags); + + mmc_cqe_request_done(mmc, hsq->mrq); + + mmc_hsq_post_request(hsq); + + return true; +} +EXPORT_SYMBOL_GPL(mmc_hsq_finalize_request); + +static void mmc_hsq_recovery_start(struct mmc_host *mmc) +{ + struct mmc_hsq *hsq = mmc->cqe_private; + unsigned long flags; + + spin_lock_irqsave(&hsq->lock, flags); + + hsq->recovery_halt = true; + + spin_unlock_irqrestore(&hsq->lock, flags); +} + +static void mmc_hsq_recovery_finish(struct mmc_host *mmc) +{ + struct mmc_hsq *hsq = mmc->cqe_private; + int remains; + + spin_lock_irq(&hsq->lock); + + hsq->recovery_halt = false; + remains = hsq->qcnt; + + spin_unlock_irq(&hsq->lock); + + /* + * Try to pump new request if there are request pending in software + * queue after finishing recovery. + */ + if (remains > 0) + mmc_hsq_pump_requests(hsq); +} + +static int mmc_hsq_request(struct mmc_host *mmc, struct mmc_request *mrq) +{ + struct mmc_hsq *hsq = mmc->cqe_private; + int tag = mrq->tag; + + spin_lock_irq(&hsq->lock); + + if (!hsq->enabled) { + spin_unlock_irq(&hsq->lock); + return -ESHUTDOWN; + } + + /* Do not queue any new requests in recovery mode. */ + if (hsq->recovery_halt) { + spin_unlock_irq(&hsq->lock); + return -EBUSY; + } + + hsq->slot[tag].mrq = mrq; + + /* + * Set the next tag as current request tag if no available + * next tag. + */ + if (hsq->next_tag == HSQ_INVALID_TAG) + hsq->next_tag = tag; + + hsq->qcnt++; + + spin_unlock_irq(&hsq->lock); + + mmc_hsq_pump_requests(hsq); + + return 0; +} + +static void mmc_hsq_post_req(struct mmc_host *mmc, struct mmc_request *mrq) +{ + if (mmc->ops->post_req) + mmc->ops->post_req(mmc, mrq, 0); +} + +static bool mmc_hsq_queue_is_idle(struct mmc_hsq *hsq, int *ret) +{ + bool is_idle; + + spin_lock_irq(&hsq->lock); + + is_idle = (!hsq->mrq && !hsq->qcnt) || + hsq->recovery_halt; + + *ret = hsq->recovery_halt ? -EBUSY : 0; + hsq->waiting_for_idle = !is_idle; + + spin_unlock_irq(&hsq->lock); + + return is_idle; +} + +static int mmc_hsq_wait_for_idle(struct mmc_host *mmc) +{ + struct mmc_hsq *hsq = mmc->cqe_private; + int ret; + + wait_event(hsq->wait_queue, + mmc_hsq_queue_is_idle(hsq, &ret)); + + return ret; +} + +static void mmc_hsq_disable(struct mmc_host *mmc) +{ + struct mmc_hsq *hsq = mmc->cqe_private; + u32 timeout = 500; + int ret; + + spin_lock_irq(&hsq->lock); + + if (!hsq->enabled) { + spin_unlock_irq(&hsq->lock); + return; + } + + spin_unlock_irq(&hsq->lock); + + ret = wait_event_timeout(hsq->wait_queue, + mmc_hsq_queue_is_idle(hsq, &ret), + msecs_to_jiffies(timeout)); + if (ret == 0) { + pr_warn("could not stop mmc software queue\n"); + return; + } + + spin_lock_irq(&hsq->lock); + + hsq->enabled = false; + + spin_unlock_irq(&hsq->lock); +} + +static int mmc_hsq_enable(struct mmc_host *mmc, struct mmc_card *card) +{ + struct mmc_hsq *hsq = mmc->cqe_private; + + spin_lock_irq(&hsq->lock); + + if (hsq->enabled) { + spin_unlock_irq(&hsq->lock); + return -EBUSY; + } + + hsq->enabled = true; + + spin_unlock_irq(&hsq->lock); + + return 0; +} + +static const struct mmc_cqe_ops mmc_hsq_ops = { + .cqe_enable = mmc_hsq_enable, + .cqe_disable = mmc_hsq_disable, + .cqe_request = mmc_hsq_request, + .cqe_post_req = mmc_hsq_post_req, + .cqe_wait_for_idle = mmc_hsq_wait_for_idle, + .cqe_recovery_start = mmc_hsq_recovery_start, + .cqe_recovery_finish = mmc_hsq_recovery_finish, +}; + +int mmc_hsq_init(struct mmc_hsq *hsq, struct mmc_host *mmc) +{ + hsq->num_slots = HSQ_NUM_SLOTS; + hsq->next_tag = HSQ_INVALID_TAG; + + hsq->slot = devm_kcalloc(mmc_dev(mmc), hsq->num_slots, + sizeof(struct hsq_slot), GFP_KERNEL); + if (!hsq->slot) + return -ENOMEM; + + hsq->mmc = mmc; + hsq->mmc->cqe_private = hsq; + mmc->cqe_ops = &mmc_hsq_ops; + + INIT_WORK(&hsq->retry_work, mmc_hsq_retry_handler); + spin_lock_init(&hsq->lock); + init_waitqueue_head(&hsq->wait_queue); + + return 0; +} +EXPORT_SYMBOL_GPL(mmc_hsq_init); + +void mmc_hsq_suspend(struct mmc_host *mmc) +{ + mmc_hsq_disable(mmc); +} +EXPORT_SYMBOL_GPL(mmc_hsq_suspend); + +int mmc_hsq_resume(struct mmc_host *mmc) +{ + return mmc_hsq_enable(mmc, NULL); +} +EXPORT_SYMBOL_GPL(mmc_hsq_resume); + +MODULE_DESCRIPTION("MMC Host Software Queue support"); +MODULE_LICENSE("GPL v2"); |