/*-
 * Copyright (c) 2013 Hans Petter Selasky. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
 */

#include <bsd_global.h>

#if USB_HAVE_BUSDMA
static void     usb_pc_common_mem_cb(struct usb_page_cache *pc,
                    void *vaddr, uint32_t length);
#endif

/*------------------------------------------------------------------------*
 *  usbd_get_page - lookup DMA-able memory for the given offset
 *
 * NOTE: Only call this function when the "page_cache" structure has
 * been properly initialized !
 *------------------------------------------------------------------------*/
void
usbd_get_page(struct usb_page_cache *pc, usb_frlength_t offset,
    struct usb_page_search *res)
{
#if USB_HAVE_BUSDMA
        struct usb_page *page;

        if (pc->page_start) {

                /* Case 1 - something has been loaded into DMA */

                if (pc->buffer) {

                        /* Case 1a - Kernel Virtual Address */

                        res->buffer = USB_ADD_BYTES(pc->buffer, offset);
                }
                offset += pc->page_offset_buf;

                /* compute destination page */

                page = pc->page_start;

                if (pc->ismultiseg) {

                        page += (offset / USB_PAGE_SIZE);

                        offset %= USB_PAGE_SIZE;

                        res->length = USB_PAGE_SIZE - offset;
                        res->physaddr = page->physaddr + offset;
                } else {
                        res->length = (usb_size_t)-1;
                        res->physaddr = page->physaddr + offset;
                }
                if (!pc->buffer) {

                        /* Case 1b - Non Kernel Virtual Address */

                        res->buffer = USB_ADD_BYTES(page->buffer, offset);
                }
                return;
        }
#endif
        /* Case 2 - Plain PIO */

        res->buffer = USB_ADD_BYTES(pc->buffer, offset);
        res->length = (usb_size_t)-1;
#if USB_HAVE_BUSDMA
        res->physaddr = 0;
#endif
}

/*------------------------------------------------------------------------*
 *  usbd_copy_in - copy directly to DMA-able memory
 *------------------------------------------------------------------------*/
void
usbd_copy_in(struct usb_page_cache *cache, usb_frlength_t offset,
    const void *ptr, usb_frlength_t len)
{
        struct usb_page_search buf_res;

        while (len != 0) {

                usbd_get_page(cache, offset, &buf_res);

                if (buf_res.length > len) {
                        buf_res.length = len;
                }
                memcpy(buf_res.buffer, ptr, buf_res.length);

                offset += buf_res.length;
                len -= buf_res.length;
                ptr = USB_ADD_BYTES(ptr, buf_res.length);
        }
}

/*------------------------------------------------------------------------*
 *  usbd_copy_out - copy directly from DMA-able memory
 *------------------------------------------------------------------------*/
void
usbd_copy_out(struct usb_page_cache *cache, usb_frlength_t offset,
    void *ptr, usb_frlength_t len)
{
        struct usb_page_search res;

        while (len != 0) {

                usbd_get_page(cache, offset, &res);

                if (res.length > len) {
                        res.length = len;
                }
                memcpy(ptr, res.buffer, res.length);

                offset += res.length;
                len -= res.length;
                ptr = USB_ADD_BYTES(ptr, res.length);
        }
}

/*------------------------------------------------------------------------*
 *  usbd_frame_zero - zero DMA-able memory
 *------------------------------------------------------------------------*/
void
usbd_frame_zero(struct usb_page_cache *cache, usb_frlength_t offset,
    usb_frlength_t len)
{
        struct usb_page_search res;

        while (len != 0) {

                usbd_get_page(cache, offset, &res);

                if (res.length > len) {
                        res.length = len;
                }
                memset(res.buffer, 0, res.length);

                offset += res.length;
                len -= res.length;
        }
}

#if USB_HAVE_BUSDMA

/*------------------------------------------------------------------------*
 *      usb_pc_common_mem_cb - BUS-DMA callback function
 *------------------------------------------------------------------------*/
static void
usb_pc_common_mem_cb(struct usb_page_cache *pc,
    void *vaddr, uint32_t length)
{
        struct usb_page *pg;
        usb_size_t rem;
        bus_size_t off;
        bus_addr_t phys = (uintptr_t)vaddr;     /* XXX */
        uint32_t nseg;

        if (length == 0)
                nseg = 1;
        else
                nseg = ((length + USB_PAGE_SIZE - 1) / USB_PAGE_SIZE);

        pg = pc->page_start;
        pg->physaddr = phys & ~(USB_PAGE_SIZE - 1);
        rem = phys & (USB_PAGE_SIZE - 1);
        pc->page_offset_buf = rem;
        pc->page_offset_end += rem;
        length += rem;

        for (off = USB_PAGE_SIZE; off < length; off += USB_PAGE_SIZE) {
                pg++;
                pg->physaddr = (phys + off) & ~(USB_PAGE_SIZE - 1);
        }
}

/*------------------------------------------------------------------------*
 *      usb_pc_alloc_mem - allocate DMA'able memory
 *
 * Returns:
 *    0: Success
 * Else: Failure
 *------------------------------------------------------------------------*/
uint8_t
usb_pc_alloc_mem(struct usb_page_cache *pc, struct usb_page *pg,
    usb_size_t size, usb_size_t align)
{
        void *ptr;
        uint32_t rem;

        /* allocate zeroed memory */

        if (align != 1) {
                ptr = malloc(size + align, XXX, XXX);
                if (ptr == NULL)
                        goto error;

                rem = (-((uintptr_t)ptr)) & (align - 1);
        } else {
                ptr = malloc(size, XXX, XXX);
                if (ptr == NULL)
                        goto error;
                rem = 0;
        }

        /* setup page cache */
        pc->buffer = ((uint8_t *)ptr) + rem;
        pc->page_start = pg;
        pc->page_offset_buf = 0;
        pc->page_offset_end = size;
        pc->map = NULL;
        pc->tag = ptr;
        pc->ismultiseg = (align == 1);

        /* compute physical address */
        usb_pc_common_mem_cb(pc, pc->buffer, size);

        usb_pc_cpu_flush(pc);
        return (0);

error:
        /* reset most of the page cache */
        pc->buffer = NULL;
        pc->page_start = NULL;
        pc->page_offset_buf = 0;
        pc->page_offset_end = 0;
        pc->map = NULL;
        pc->tag = NULL;
        return (1);
}

/*------------------------------------------------------------------------*
 *      usb_pc_free_mem - free DMA memory
 *
 * This function is NULL safe.
 *------------------------------------------------------------------------*/
void
usb_pc_free_mem(struct usb_page_cache *pc)
{
        if (pc != NULL && pc->buffer != NULL) {
                free(pc->tag, XXX);
                pc->buffer = NULL;
        }
}

/*------------------------------------------------------------------------*
 *      usb_pc_load_mem - load virtual memory into DMA
 *
 * Return values:
 * 0: Success
 * Else: Error
 *------------------------------------------------------------------------*/
uint8_t
usb_pc_load_mem(struct usb_page_cache *pc, usb_size_t size, uint8_t sync)
{
        /* setup page cache */
        pc->page_offset_buf = 0;
        pc->page_offset_end = size;
        pc->ismultiseg = 1;

        mtx_assert(pc->tag_parent->mtx, MA_OWNED);

        if (size > 0) {
                /* compute physical address */
                usb_pc_common_mem_cb(pc, pc->buffer, size);
        }
        if (sync == 0) {
                /*
                 * Call callback so that refcount is decremented
                 * properly:
                 */
                pc->tag_parent->dma_error = 0;
                (pc->tag_parent->func) (pc->tag_parent);
        }
        return (0);
}

/*------------------------------------------------------------------------*
 *      usb_pc_cpu_invalidate - invalidate CPU cache
 *------------------------------------------------------------------------*/
void
usb_pc_cpu_invalidate(struct usb_page_cache *pc)
{
        if (pc->page_offset_end == pc->page_offset_buf) {
                /* nothing has been loaded into this page cache! */
                return;
        }
        /* NOP */
}

/*------------------------------------------------------------------------*
 *      usb_pc_cpu_flush - flush CPU cache
 *------------------------------------------------------------------------*/
void
usb_pc_cpu_flush(struct usb_page_cache *pc)
{
        if (pc->page_offset_end == pc->page_offset_buf) {
                /* nothing has been loaded into this page cache! */
                return;
        }
        /* NOP */
}

/*------------------------------------------------------------------------*
 *      usb_pc_dmamap_create - create a DMA map
 *
 * Returns:
 *    0: Success
 * Else: Failure
 *------------------------------------------------------------------------*/
uint8_t
usb_pc_dmamap_create(struct usb_page_cache *pc, usb_size_t size)
{
        return (0);     /* NOP, success */
}

/*------------------------------------------------------------------------*
 *      usb_pc_dmamap_destroy
 *
 * This function is NULL safe.
 *------------------------------------------------------------------------*/
void
usb_pc_dmamap_destroy(struct usb_page_cache *pc)
{
        /* NOP */
}

/*------------------------------------------------------------------------*
 *      usb_dma_tag_setup - initialise USB DMA tags
 *------------------------------------------------------------------------*/
void
usb_dma_tag_setup(struct usb_dma_parent_tag *udpt,
    struct usb_dma_tag *udt, bus_dma_tag_t dmat,
    struct mtx *mtx, usb_dma_callback_t *func,
    uint8_t ndmabits, uint8_t nudt)
{
        memset(udpt, 0, sizeof(*udpt));

        /* sanity checking */
        if ((nudt == 0) ||
            (ndmabits == 0) ||
            (mtx == NULL)) {
                /* something is corrupt */
                return;
        }
        /* initialise condition variable */
        cv_init(udpt->cv, "USB DMA CV");

        /* store some information */
        udpt->mtx = mtx;
        udpt->func = func;
        udpt->tag = dmat;
        udpt->utag_first = udt;
        udpt->utag_max = nudt;
        udpt->dma_bits = ndmabits;

        while (nudt--) {
                memset(udt, 0, sizeof(*udt));
                udt->tag_parent = udpt;
                udt++;
        }
}

/*------------------------------------------------------------------------*
 *      usb_bus_tag_unsetup - factored out code
 *------------------------------------------------------------------------*/
void
usb_dma_tag_unsetup(struct usb_dma_parent_tag *udpt)
{
        struct usb_dma_tag *udt;
        uint8_t nudt;

        udt = udpt->utag_first;
        nudt = udpt->utag_max;

        while (nudt--) {
                udt->align = 0;
                udt++;
        }

        if (udpt->utag_max) {
                /* destroy the condition variable */
                cv_destroy(udpt->cv);
        }
}

/*------------------------------------------------------------------------*
 *      usb_bdma_work_loop
 *
 * This function handles loading of virtual buffers into DMA and is
 * only called when "dma_refcount" is zero.
 *------------------------------------------------------------------------*/
void
usb_bdma_work_loop(struct usb_xfer_queue *pq)
{
        struct usb_xfer_root *info;
        struct usb_xfer *xfer;
        usb_frcount_t nframes;

        xfer = pq->curr;
        info = xfer->xroot;

        mtx_assert(info->xfer_mtx, MA_OWNED);

        if (xfer->error) {
                /* some error happened */
                USB_BUS_LOCK(info->bus);
                usbd_transfer_done(xfer, 0);
                USB_BUS_UNLOCK(info->bus);
                return;
        }
        if (!xfer->flags_int.bdma_setup) {
                struct usb_page *pg;
                usb_frlength_t frlength_0;
                uint8_t isread;

                xfer->flags_int.bdma_setup = 1;

                /* reset BUS-DMA load state */

                info->dma_error = 0;

                if (xfer->flags_int.isochronous_xfr) {
                        /* only one frame buffer */
                        nframes = 1;
                        frlength_0 = xfer->sumlen;
                } else {
                        /* can be multiple frame buffers */
                        nframes = xfer->nframes;
                        frlength_0 = xfer->frlengths[0];
                }

                /*
                 * Set DMA direction first. This is needed to
                 * select the correct cache invalidate and cache
                 * flush operations.
                 */
                isread = USB_GET_DATA_ISREAD(xfer);
                pg = xfer->dma_page_ptr;

                if (xfer->flags_int.control_xfr &&
                    xfer->flags_int.control_hdr) {
                        /* special case */
                        if (xfer->flags_int.usb_mode == USB_MODE_DEVICE) {
                                /* The device controller writes to memory */
                                xfer->frbuffers[0].isread = 1;
                        } else {
                                /* The host controller reads from memory */
                                xfer->frbuffers[0].isread = 0;
                        }
                } else {
                        /* default case */
                        xfer->frbuffers[0].isread = isread;
                }

                /*
                 * Setup the "page_start" pointer which points to an array of
                 * USB pages where information about the physical address of a
                 * page will be stored. Also initialise the "isread" field of
                 * the USB page caches.
                 */
                xfer->frbuffers[0].page_start = pg;

                info->dma_nframes = nframes;
                info->dma_currframe = 0;
                info->dma_frlength_0 = frlength_0;

                pg += (frlength_0 / USB_PAGE_SIZE);
                pg += 2;

                while (--nframes > 0) {
                        xfer->frbuffers[nframes].isread = isread;
                        xfer->frbuffers[nframes].page_start = pg;

                        pg += (xfer->frlengths[nframes] / USB_PAGE_SIZE);
                        pg += 2;
                }

        }
        if (info->dma_error) {
                USB_BUS_LOCK(info->bus);
                usbd_transfer_done(xfer, USB_ERR_DMA_LOAD_FAILED);
                USB_BUS_UNLOCK(info->bus);
                return;
        }
        if (info->dma_currframe != info->dma_nframes) {

                if (info->dma_currframe == 0) {
                        /* special case */
                        usb_pc_load_mem(xfer->frbuffers,
                            info->dma_frlength_0, 0);
                } else {
                        /* default case */
                        nframes = info->dma_currframe;
                        usb_pc_load_mem(xfer->frbuffers + nframes,
                            xfer->frlengths[nframes], 0);
                }

                /* advance frame index */
                info->dma_currframe++;

                return;
        }
        /* go ahead */
        usb_bdma_pre_sync(xfer);

        /* start loading next USB transfer, if any */
        usb_command_wrapper(pq, NULL);

        /* finally start the hardware */
        usbd_pipe_enter(xfer);
}

/*------------------------------------------------------------------------*
 *      usb_bdma_done_event
 *
 * This function is called when the BUS-DMA has loaded virtual memory
 * into DMA, if any.
 *------------------------------------------------------------------------*/
void
usb_bdma_done_event(struct usb_dma_parent_tag *udpt)
{
        struct usb_xfer_root *info;

        info = USB_DMATAG_TO_XROOT(udpt);

        mtx_assert(info->xfer_mtx, MA_OWNED);

        /* copy error */
        info->dma_error = udpt->dma_error;

        /* enter workloop again */
        usb_command_wrapper(&info->dma_q,
            info->dma_q.curr);
}

/*------------------------------------------------------------------------*
 *      usb_bdma_pre_sync
 *
 * This function handles DMA synchronisation that must be done before
 * an USB transfer is started.
 *------------------------------------------------------------------------*/
void
usb_bdma_pre_sync(struct usb_xfer *xfer)
{
        struct usb_page_cache *pc;
        usb_frcount_t nframes;

        if (xfer->flags_int.isochronous_xfr) {
                /* only one frame buffer */
                nframes = 1;
        } else {
                /* can be multiple frame buffers */
                nframes = xfer->nframes;
        }

        pc = xfer->frbuffers;

        while (nframes--) {

                if (pc->isread) {
                        usb_pc_cpu_invalidate(pc);
                } else {
                        usb_pc_cpu_flush(pc);
                }
                pc++;
        }
}

/*------------------------------------------------------------------------*
 *      usb_bdma_post_sync
 *
 * This function handles DMA synchronisation that must be done after
 * an USB transfer is complete.
 *------------------------------------------------------------------------*/
void
usb_bdma_post_sync(struct usb_xfer *xfer)
{
        struct usb_page_cache *pc;
        usb_frcount_t nframes;

        if (xfer->flags_int.isochronous_xfr) {
                /* only one frame buffer */
                nframes = 1;
        } else {
                /* can be multiple frame buffers */
                nframes = xfer->nframes;
        }

        pc = xfer->frbuffers;

        while (nframes--) {
                if (pc->isread) {
                        usb_pc_cpu_invalidate(pc);
                }
                pc++;
        }
}
#endif