source: trunk/kernel/syscalls/sys_dma_memcpy.c @ 5

/*
 * kern/sys_dma_memcpy.c - exported DMA access to user process
 * 
 * Copyright (c) 2008,2009,2010,2011,2012 Ghassan Almaless
 * Copyright (c) 2011,2012 UPMC Sorbonne Universites
 *
 * This file is part of ALMOS-kernel.
 *
 * ALMOS-kernel is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2.0 of the License.
 *
 * ALMOS-kernel is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with ALMOS-kernel; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <errno.h>
#include <types.h>
#include <event.h>
#include <device.h>
#include <driver.h>
#include <kmem.h>
#include <kdmsg.h>
#include <dma.h>
#include <kcm.h>
#include <thread.h>
#include <cluster.h>
#include <kcm.h>


KMEM_OBJATTR_INIT(dma_kmem_request_init)
{
        attr->type = KMEM_DMA_REQUEST;
        attr->name = "KCM Dev-Request";
        attr->size = sizeof(dev_request_t);
        attr->aligne = 0;
        attr->min  = CONFIG_DMA_RQ_KCM_MIN;
        attr->max  = CONFIG_DMA_RQ_KCM_MAX;
        attr->ctor = NULL;
        attr->dtor = NULL;
  
        return 0;
}

static EVENT_HANDLER(dma_async_request_event)
{
        kmem_req_t req;
        error_t err;
  
        if((err=event_get_error(event)) != 0)
                printk(ERROR, "ERROR: dma_async_request_event: DMA transfare is not well completed, remaining %d\n", err);

        req.type = KMEM_DMA_REQUEST;
        req.ptr  = event_get_argument(event);

        assert(req.ptr != NULL && "Corrupted argument, expected the address of request");

        kmem_free(&req);
        return 0;
}

static inline error_t dma_do_async_request(void *dst, void *src, size_t size)
{
        kmem_req_t req;
        dev_request_t *rq;
  
        req.type  = KMEM_DMA_REQUEST;
        req.size  = sizeof(*rq);
        req.flags = AF_KERNEL;

        if((rq = kmem_alloc(&req)) == NULL)
                return ENOMEM;

        memset(rq, 0, sizeof(*rq));

        rq->src   = src;
        rq->dst   = dst;
        rq->count = size;
        rq->flags = DEV_RQ_NOBLOCK;

        event_set_priority(&rq->event, E_FUNC);
        event_set_handler(&rq->event, &dma_async_request_event);
        event_set_argument(&rq->event, rq);
  
        return __sys_dma->op.dev.write(__sys_dma, rq);
}

static inline error_t dma_do_sync_request(void *dst, void *src, size_t size)
{
        dev_request_t rq;
  
        rq.src   = src;
        rq.dst   = dst;
        rq.count = size;
        rq.flags = 0;
  
        return __sys_dma->op.dev.write(__sys_dma, &rq);
}


error_t dma_memcpy(void *dst, void *src, size_t size, uint_t isAsync)
{
        if(isAsync == DMA_ASYNC)
                return dma_do_async_request(dst, src, size);
        else
                return dma_do_sync_request(dst, src, size);
}


int sys_dma_memcpy(void *src, void *dst, size_t size)
{
        return dma_do_sync_request(dst, src, size);
}