On Thu, Oct 23, 2014 at 10:22:18AM +0800, Robin Gong wrote:
> -static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
> - struct dma_chan *chan, struct scatterlist *sgl,
> - unsigned int sg_len, enum dma_transfer_direction direction,
> - unsigned long flags, void *context)
> +static struct dma_async_tx_descriptor *sdma_prep_memcpy(
> + struct dma_chan *chan, dma_addr_t dma_dst,
> + dma_addr_t dma_src, size_t len, unsigned long flags)
> +{
> + struct sdma_channel *sdmac = to_sdma_chan(chan);
> + struct sdma_engine *sdma = sdmac->sdma;
> + int channel = sdmac->channel;
> + size_t count;
> + int i = 0, param, ret;
> + struct sdma_buffer_descriptor *bd;
> +
> + if (!chan || !len || sdmac->status == DMA_IN_PROGRESS)
> + return NULL;
why is this dependent on status. You can prepare a descriptor here!
> +
> + if (len >= NUM_BD * SDMA_BD_MAX_CNT) {
> + dev_err(sdma->dev, "channel%d: maximum bytes exceeded:%d >
> %d\n",
> + channel, len, NUM_BD * SDMA_BD_MAX_CNT);
> + goto err_out;
> + }
> +
> + sdmac->status = DMA_IN_PROGRESS;
??
> +
> + sdmac->buf_tail = 0;
> +
> + dev_dbg(sdma->dev, "memcpy: %x->%x, len=%d, channel=%d.\n",
> + dma_src, dma_dst, len, channel);
> +
> + sdmac->direction = DMA_MEM_TO_MEM;
> +
> + ret = sdma_load_context(sdmac);
> + if (ret)
> + goto err_out;
> +
> + sdmac->chn_count = 0;
> +
> + do {
> + count = min_t(size_t, len, SDMA_BD_MAX_CNT);
> + bd = &sdmac->bd[i];
> + bd->buffer_addr = dma_src;
> + bd->ext_buffer_addr = dma_dst;
> + bd->mode.count = count;
> +
> + if (sdmac->word_size > DMA_SLAVE_BUSWIDTH_4_BYTES) {
> + ret = -EINVAL;
> + goto err_out;
> + }
> +
> + switch (sdmac->word_size) {
> + case DMA_SLAVE_BUSWIDTH_4_BYTES:
So are you dependent of dma_slave_config to be set. Then it is wrong. for
memcpy you shoudn't be!
> switch (sdmac->word_size) {
> case DMA_SLAVE_BUSWIDTH_4_BYTES:
> bd->mode.command = 0;
> - if (count & 3 || sg->dma_address & 3)
> + if ((count | sg_src->dma_address | (sg_dst &&
> + (sg_dst->dma_address))) & 3)
> return NULL;
> break;
> case DMA_SLAVE_BUSWIDTH_2_BYTES:
> bd->mode.command = 2;
> - if (count & 1 || sg->dma_address & 1)
> + if ((count | sg_src->dma_address |
> + (sg_dst && (sg_dst->dma_address))) & 1)
> return NULL;
this doesn't seem to have anything to do with memcpy, shouldn't this be
independent change here?
> break;
> case DMA_SLAVE_BUSWIDTH_1_BYTE:
> @@ -1099,21 +1214,23 @@ static struct dma_async_tx_descriptor
> *sdma_prep_slave_sg(
>
> param = BD_DONE | BD_EXTD | BD_CONT;
>
> - if (i + 1 == sg_len) {
> + if (i + 1 == src_nents) {
> param |= BD_INTR;
> param |= BD_LAST;
> param &= ~BD_CONT;
> }
>
> - dev_dbg(sdma->dev, "entry %d: count: %d dma: %#llx %s%s\n",
> - i, count, (u64)sg->dma_address,
> + dev_dbg(sdma->dev, "entry %d: count: %d dma: 0x%08x %s%s\n",
> + i, count, sg_src->dma_address,
> param & BD_WRAP ? "wrap" : "",
> param & BD_INTR ? " intr" : "");
ditto
>
> bd->mode.status = param;
> + if (direction == DMA_MEM_TO_MEM)
> + sg_dst = sg_next(sg_dst);
> }
>
> - sdmac->num_bd = sg_len;
> + sdmac->num_bd = src_nents;
> sdma->channel_control[channel].current_bd_ptr = sdmac->bd_phys;
>
> return &sdmac->desc;
> @@ -1122,6 +1239,24 @@ err_out:
> return NULL;
> }
>
> +static struct dma_async_tx_descriptor *sdma_prep_memcpy_sg(
> + struct dma_chan *chan,
> + struct scatterlist *dst_sg, unsigned int dst_nents,
> + struct scatterlist *src_sg, unsigned int src_nents,
> + unsigned long flags)
> +{
> + return sdma_prep_sg(chan, dst_sg, dst_nents, src_sg, src_nents,
> + DMA_MEM_TO_MEM);
> +}
> +
> +static struct dma_async_tx_descriptor *sdma_prep_slave_sg(
> + struct dma_chan *chan, struct scatterlist *sgl,
> + unsigned int sg_len, enum dma_transfer_direction direction,
> + unsigned long flags, void *context)
> +{
> + return sdma_prep_sg(chan, NULL, 0, sgl, sg_len, direction);
> +}
you should have done this first and then added memcpy
--
~Vinod
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