source: mainline/uspace/drv/uhci-hcd/transfer_list.c@ 17ceb72

/*
 * 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 "transfer_list.h"

static void transfer_list_remove_batch(
    transfer_list_t *instance, batch_t *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;
        }
        instance->queue_head_pa = addr_to_phys(instance->queue_head);

        qh_init(instance->queue_head);
        list_initialize(&instance->batch_list);
        fibril_mutex_initialize(&instance->guard);
        return EOK;
}
/*----------------------------------------------------------------------------*/
/** 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(next);
        if (!instance->queue_head)
                return;
        /* Set both next and element to point to the same QH */
        qh_set_next_qh(instance->queue_head, next->queue_head_pa);
        qh_set_element_qh(instance->queue_head, next->queue_head_pa);
}
/*----------------------------------------------------------------------------*/
/** Submit transfer batch to the list and queue.
 *
 * @param[in] instance List to use.
 * @param[in] batch Transfer batch to submit.
 * @return Error code
 *
 * The batch is added to the end of the list and queue.
 */
void transfer_list_add_batch(transfer_list_t *instance, batch_t *batch)
{
        assert(instance);
        assert(batch);
        usb_log_debug2("Queue %s: Adding batch(%p).\n", instance->name, batch);

        const uint32_t pa = addr_to_phys(batch->qh);
        assert((pa & LINK_POINTER_ADDRESS_MASK) == pa);

        /* New batch will be added to the end of the current list
         * so set the link accordingly */
        qh_set_next_qh(batch->qh, instance->queue_head->next);

        fibril_mutex_lock(&instance->guard);

        /* Add to the hardware queue. */
        if (list_empty(&instance->batch_list)) {
                /* There is nothing scheduled */
                qh_t *qh = instance->queue_head;
                assert(qh->element == qh->next);
                qh_set_element_qh(qh, pa);
        } else {
                /* There is something scheduled */
                batch_t *last = list_get_instance(
                    instance->batch_list.prev, batch_t, link);
                qh_set_next_qh(last->qh, pa);
        }
        /* Add to the driver list */
        list_append(&batch->link, &instance->batch_list);

        batch_t *first = list_get_instance(
            instance->batch_list.next, batch_t, link);
        usb_log_debug("Batch(%p) added to queue %s, first is %p.\n",
                batch, instance->name, first);
        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.
 * @return Error code
 *
 * Does not lock the transfer list, caller is responsible for that.
 */
void transfer_list_remove_batch(transfer_list_t *instance, batch_t *batch)
{
        assert(instance);
        assert(batch);
        assert(instance->queue_head);
        assert(batch->qh);
        usb_log_debug2(
            "Queue %s: removing batch(%p).\n", instance->name, batch);

        const char * pos = NULL;
        /* Remove from the hardware queue */
        if (batch->link.prev == &instance->batch_list) {
                /* I'm the first one here */
                qh_set_element_qh(instance->queue_head, batch->qh->next);
                pos = "FIRST";
        } else {
                batch_t *prev =
                    list_get_instance(batch->link.prev, batch_t, link);
                qh_set_next_qh(prev->qh, batch->qh->next);
                pos = "NOT FIRST";
        }
        /* Remove from the driver list */
        list_remove(&batch->link);
        usb_log_debug("Batch(%p) removed (%s) from %s, next element %x.\n",
            batch, pos, instance->name, batch->qh->next);
}
/*----------------------------------------------------------------------------*/
/** Check list for finished batches.
 *
 * @param[in] instance List to use.
 * @return Error code
 *
 * Creates a local list of finished batches and calls next_step on each and
 * every one. This is safer because next_step may theoretically access
 * this transfer list leading to the deadlock if its done inline.
 */
void transfer_list_remove_finished(transfer_list_t *instance)
{
        assert(instance);

        LIST_INITIALIZE(done);

        fibril_mutex_lock(&instance->guard);
        link_t *current = instance->batch_list.next;
        while (current != &instance->batch_list) {
                link_t *next = current->next;
                batch_t *batch = list_get_instance(current, batch_t, link);

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

        while (!list_empty(&done)) {
                link_t *item = done.next;
                list_remove(item);
                batch_t *batch = list_get_instance(item, batch_t, link);
                batch->next_step(batch);
        }
}
/**
 * @}
 */