src/spu/internal/dma/imoc_dma-get_spu.c

Go to the documentation of this file.

#include <spu_mfcio.h>
#include <string.h>

#include <moc.h>
#include <internal/imoc_macros.h>
#include <internal/spu/imoc_dma_spu.h>

int IMOC_get_data(void* target, uint64_t source, uint32_t size)
    {
    uint32_t remainder_16b;
    uint32_t remainder_16kb;
    uint32_t offset;
    uint32_t tag_id;
    char buffer[16];

    if ((tag_id = mfc_tag_reserve()) == MFC_TAG_INVALID)
        {
        return MOC_ERR_INTERN;
        }

    /* transfers have to be multiples of 16 bytes */
    remainder_16b = size % 16;

    /* subtracting remainder means the transfer has a valid size now */
    size -= remainder_16b;
    offset = 0;

    /* first case: transfer of size smaller than maximum allowed one (16kbyte) */
    if (size <= MAX_DMA_CALL_SIZE)
        {
        mfc_get(target, source, size, tag_id, 0, 0);
        }
    /* second case: transfer of bigger size is simply split into parts of 16kb */
    else
        {
        remainder_16kb = size % MAX_DMA_CALL_SIZE;
        while (offset + MAX_DMA_CALL_SIZE <= size)
            {
            mfc_get(target + offset, source + offset, MAX_DMA_CALL_SIZE,
                    tag_id, 0, 0);
            offset += MAX_DMA_CALL_SIZE;
            }
        if (remainder_16kb > 0)
            {
            mfc_get(target + offset, source + offset, remainder_16kb, tag_id,
                    0, 0);
            }
        }
    /* if size was reduced previously the remaining bytes have to be transfered */
    if (remainder_16b > 0)
        {
        /* minimum allowed transfer is 16bytes so transfer this size into a buffer */
        mfc_get(buffer, source + size, 16, tag_id, 0, 0);
        /* waiting for dma completion necessary */
        mfc_write_tag_mask(1 << tag_id);
        mfc_read_tag_status_all();
        /* copy only the valid bytes into the target buffer */
        memcpy(target + size, buffer, remainder_16b);
        }
    else
        {
        /* waiting for dma completion necessary */
        mfc_write_tag_mask(1 << tag_id);
        mfc_read_tag_status_all();
        }

    mfc_tag_release(tag_id);
    return MOC_SUCCESS;
    }

---