// SPDX-License-Identifier: GPL-1.0+
/*
 * OHCI HCD (Host Controller Driver) for USB.
 *
 * (C) Copyright 1999 Roman Weissgaerber <weissg@vienna.at>
 * (C) Copyright 2000-2002 David Brownell <dbrownell@users.sourceforge.net>
 *
 * This file is licenced under the GPL.
 */

/*-------------------------------------------------------------------------*/

/*
 * OHCI deals with three types of memory:
 *      - data used only by the HCD ... kmalloc is fine
 *      - async and periodic schedules, shared by HC and HCD ... these
 *        need to use dma_pool or dma_alloc_coherent
 *      - driver buffers, read/written by HC ... the hcd glue or the
 *        device driver provides us with dma addresses
 *
 * There's also "register" data, which is memory mapped.
 * No memory seen by this driver (or any HCD) may be paged out.
 */

/*-------------------------------------------------------------------------*/

static void ohci_hcd_init (struct ohci_hcd *ohci)
{
        ohci->next_statechange = jiffies;
        spin_lock_init (&ohci->lock);
        INIT_LIST_HEAD (&ohci->pending);
        INIT_LIST_HEAD(&ohci->eds_in_use);
}

/*-------------------------------------------------------------------------*/

static int ohci_mem_init (struct ohci_hcd *ohci)
{
        /*
         * HCs with local memory allocate from localmem_pool so there's
         * no need to create the below dma pools.
         */
        if (ohci_to_hcd(ohci)->localmem_pool)
                return 0;

        ohci->td_cache = dma_pool_create ("ohci_td",
                ohci_to_hcd(ohci)->self.controller,
                sizeof (struct td),
                32 /* byte alignment */,
                0 /* no page-crossing issues */);
        if (!ohci->td_cache)
                return -ENOMEM;
        ohci->ed_cache = dma_pool_create ("ohci_ed",
                ohci_to_hcd(ohci)->self.controller,
                sizeof (struct ed),
                16 /* byte alignment */,
                0 /* no page-crossing issues */);
        if (!ohci->ed_cache) {
                dma_pool_destroy (ohci->td_cache);
                return -ENOMEM;
        }
        return 0;
}

static void ohci_mem_cleanup (struct ohci_hcd *ohci)
{
        dma_pool_destroy(ohci->td_cache);
        ohci->td_cache = NULL;
        dma_pool_destroy(ohci->ed_cache);
        ohci->ed_cache = NULL;
}

/*-------------------------------------------------------------------------*/

/* ohci "done list" processing needs this mapping */
static inline struct td *
dma_to_td (struct ohci_hcd *hc, dma_addr_t td_dma)
{
        struct td *td;

        td_dma &= TD_MASK;
        td = hc->td_hash [TD_HASH_FUNC(td_dma)];
        while (td && td->td_dma != td_dma)
                td = td->td_hash;
        return td;
}

/* TDs ... */
static struct td *
td_alloc (struct ohci_hcd *hc, gfp_t mem_flags)
{
        dma_addr_t      dma;
        struct td       *td;
        struct usb_hcd  *hcd = ohci_to_hcd(hc);

        if (hcd->localmem_pool)
                td = gen_pool_dma_zalloc_align(hcd->localmem_pool,
                                sizeof(*td), &dma, 32);
        else
                td = dma_pool_zalloc(hc->td_cache, mem_flags, &dma);
        if (td) {
                /* in case hc fetches it, make it look dead */
                td->hwNextTD = cpu_to_hc32 (hc, dma);
                td->td_dma = dma;
                /* hashed in td_fill */
        }
        return td;
}

static void
td_free (struct ohci_hcd *hc, struct td *td)
{
        struct td       **prev = &hc->td_hash [TD_HASH_FUNC (td->td_dma)];
        struct usb_hcd  *hcd = ohci_to_hcd(hc);

        while (*prev && *prev != td)
                prev = &(*prev)->td_hash;
        if (*prev)
                *prev = td->td_hash;
        else if ((td->hwINFO & cpu_to_hc32(hc, TD_DONE)) != 0)
                ohci_dbg (hc, "no hash for td %p\n", td);

        if (hcd->localmem_pool)
                gen_pool_free(hcd->localmem_pool, (unsigned long)td,
                              sizeof(*td));
        else
                dma_pool_free(hc->td_cache, td, td->td_dma);
}

/*-------------------------------------------------------------------------*/

/* EDs ... */
static struct ed *
ed_alloc (struct ohci_hcd *hc, gfp_t mem_flags)
{
        dma_addr_t      dma;
        struct ed       *ed;
        struct usb_hcd  *hcd = ohci_to_hcd(hc);

        if (hcd->localmem_pool)
                ed = gen_pool_dma_zalloc_align(hcd->localmem_pool,
                                sizeof(*ed), &dma, 16);
        else
                ed = dma_pool_zalloc(hc->ed_cache, mem_flags, &dma);
        if (ed) {
                INIT_LIST_HEAD (&ed->td_list);
                ed->dma = dma;
        }
        return ed;
}

static void
ed_free (struct ohci_hcd *hc, struct ed *ed)
{
        struct usb_hcd  *hcd = ohci_to_hcd(hc);

        if (hcd->localmem_pool)
                gen_pool_free(hcd->localmem_pool, (unsigned long)ed,
                              sizeof(*ed));
        else
                dma_pool_free(hc->ed_cache, ed, ed->dma);
}