source: mainline/uspace/drv/bus/usb/uhci/transfer_list.c@ a5c2eb5f

/*
 * Copyright (c) 2011 Jan Vesely
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup drvusbuhcihc
 * @{
 */
/** @file
 * @brief UHCI driver transfer list implementation
 */

#include <errno.h>
#include <usb/debug.h>
#include <libarch/barrier.h>

#include "transfer_list.h"

static void transfer_list_remove_batch(
    transfer_list_t *instance, uhci_transfer_batch_t *uhci_batch);

/** Initialize transfer list structures.
 *
 * @param[in] instance Memory place to use.
 * @param[in] name Name of the new list.
 * @return Error code
 *
 * Allocates memory for internal qh_t structure.
 */
int transfer_list_init(transfer_list_t *instance, const char *name)
{
        assert(instance);
        instance->name = name;
        instance->queue_head = malloc32(sizeof(qh_t));
        if (!instance->queue_head) {
                usb_log_error("Failed to allocate queue head.\n");
                return ENOMEM;
        }
        const uint32_t queue_head_pa = addr_to_phys(instance->queue_head);
        usb_log_debug2("Transfer list %s setup with QH: %p (%#" PRIx32" ).\n",
            name, instance->queue_head, queue_head_pa);

        qh_init(instance->queue_head);
        list_initialize(&instance->batch_list);
        fibril_mutex_initialize(&instance->guard);
        return EOK;
}

/** Dispose transfer list structures.
 *
 * @param[in] instance Memory place to use.
 *
 * Frees memory of the internal qh_t structure.
 */
void transfer_list_fini(transfer_list_t *instance)
{
        assert(instance);
        free32(instance->queue_head);
}
/** Set the next list in transfer list chain.
 *
 * @param[in] instance List to lead.
 * @param[in] next List to append.
 * @return Error code
 *
 * Does not check whether this replaces an existing list .
 */
void transfer_list_set_next(transfer_list_t *instance, transfer_list_t *next)
{
        assert(instance);
        assert(instance->queue_head);
        assert(next);
        /* Set queue_head.next to point to the follower */
        qh_set_next_qh(instance->queue_head, next->queue_head);
}

/** Add transfer batch to the list and queue.
 *
 * @param[in] instance List to use.
 * @param[in] batch Transfer batch to submit.
 *
 * The batch is added to the end of the list and queue.
 */
void transfer_list_add_batch(
    transfer_list_t *instance, uhci_transfer_batch_t *uhci_batch)
{
        assert(instance);
        assert(uhci_batch);
        usb_log_debug2("Batch %p adding to queue %s.\n",
            uhci_batch->usb_batch, instance->name);

        fibril_mutex_lock(&instance->guard);

        /* Assume there is nothing scheduled */
        qh_t *last_qh = instance->queue_head;
        /* There is something scheduled */
        if (!list_empty(&instance->batch_list)) {
                last_qh = uhci_transfer_batch_from_link(
                    list_last(&instance->batch_list))->qh;
        }
        /* Add to the hardware queue. */
        const uint32_t pa = addr_to_phys(uhci_batch->qh);
        assert((pa & LINK_POINTER_ADDRESS_MASK) == pa);

        /* Make sure all data in the batch are written */
        write_barrier();

        /* keep link */
        uhci_batch->qh->next = last_qh->next;
        qh_set_next_qh(last_qh, uhci_batch->qh);

        /* Make sure the pointer is updated */
        write_barrier();

        /* Add to the driver's list */
        list_append(&uhci_batch->link, &instance->batch_list);

        usb_log_debug2("Batch %p " USB_TRANSFER_BATCH_FMT
            " scheduled in queue %s.\n", uhci_batch->usb_batch,
            USB_TRANSFER_BATCH_ARGS(*uhci_batch->usb_batch), instance->name);
        fibril_mutex_unlock(&instance->guard);
}

/** Add completed batches to the provided list.
 *
 * @param[in] instance List to use.
 * @param[in] done list to fill
 */
void transfer_list_remove_finished(transfer_list_t *instance, list_t *done)
{
        assert(instance);
        assert(done);

        fibril_mutex_lock(&instance->guard);
        link_t *current = list_first(&instance->batch_list);
        while (current && current != &instance->batch_list.head) {
                link_t * const next = current->next;
                uhci_transfer_batch_t *batch =
                    uhci_transfer_batch_from_link(current);

                if (uhci_transfer_batch_is_complete(batch)) {
                        /* Save for processing */
                        transfer_list_remove_batch(instance, batch);
                        list_append(current, done);
                }
                current = next;
        }
        fibril_mutex_unlock(&instance->guard);
}

/** Walk the list and finish all batches with EINTR.
 *
 * @param[in] instance List to use.
 */
void transfer_list_abort_all(transfer_list_t *instance)
{
        fibril_mutex_lock(&instance->guard);
        while (!list_empty(&instance->batch_list)) {
                link_t * const current = list_first(&instance->batch_list);
                uhci_transfer_batch_t *batch =
                    uhci_transfer_batch_from_link(current);
                transfer_list_remove_batch(instance, batch);
                uhci_transfer_batch_abort(batch);
        }
        fibril_mutex_unlock(&instance->guard);
}

/** Remove a transfer batch from the list and queue.
 *
 * @param[in] instance List to use.
 * @param[in] batch Transfer batch to remove.
 *
 * Does not lock the transfer list, caller is responsible for that.
 */
void transfer_list_remove_batch(
    transfer_list_t *instance, uhci_transfer_batch_t *uhci_batch)
{
        assert(instance);
        assert(instance->queue_head);
        assert(uhci_batch);
        assert(uhci_batch->qh);
        assert(fibril_mutex_is_locked(&instance->guard));

        usb_log_debug2("Batch %p removing from queue %s.\n",
            uhci_batch->usb_batch, instance->name);

        /* Assume I'm the first */
        const char *qpos = "FIRST";
        qh_t *prev_qh = instance->queue_head;
        /* Remove from the hardware queue */
        if (list_first(&instance->batch_list) != &uhci_batch->link) {
                /* There is a batch in front of me */
                prev_qh =
                    uhci_transfer_batch_from_link(uhci_batch->link.prev)->qh;
                qpos = "NOT FIRST";
        }
        assert((prev_qh->next & LINK_POINTER_ADDRESS_MASK)
            == addr_to_phys(uhci_batch->qh));
        prev_qh->next = uhci_batch->qh->next;

        /* Make sure the pointer is updated */
        write_barrier();

        /* Remove from the batch list */
        list_remove(&uhci_batch->link);
        usb_log_debug2("Batch %p " USB_TRANSFER_BATCH_FMT " removed (%s) "
            "from %s, next: %x.\n", uhci_batch->usb_batch,
            USB_TRANSFER_BATCH_ARGS(*uhci_batch->usb_batch),
            qpos, instance->name, uhci_batch->qh->next);
}
/**
 * @}
 */