On Tue, Oct 25, 2016 at 01:50:19PM +0300, Peter Ujfalusi wrote:
> Based on the src/dst_port_window_size - if it is set - configure the DMA
> channel to use double indexing in order to be able to loop within the
> address window.
>
> Signed-off-by: Peter Ujfalusi <[email protected]>
> ---
> drivers/dma/omap-dma.c | 45 +++++++++++++++++++++++++++++++++++++++++++--
> 1 file changed, 43 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/dma/omap-dma.c b/drivers/dma/omap-dma.c
> index 025f499cb20d..29350f936154 100644
> --- a/drivers/dma/omap-dma.c
> +++ b/drivers/dma/omap-dma.c
> @@ -166,6 +166,9 @@ enum {
> CSDP_DST_BURST_16 = 1 << 14,
> CSDP_DST_BURST_32 = 2 << 14,
> CSDP_DST_BURST_64 = 3 << 14,
> + CSDP_WRITE_NON_POSTED = (0 << 16),
> + CSDP_WRITE_POSTED = (1 << 16),
> + CSDP_WRITE_LAST_NON_POSTED = (2 << 16),
Why the useless parens?
> + if (port_window) {
> + d->ccr |= CCR_SRC_AMODE_DBLIDX;
> + d->ei = 1;
> + d->fi = (-1) * (port_window - 1);
You know that's 1 - port_window, or -(port_window - 1).
> +
> + if (port_window / 64)
> + d->csdp = CSDP_SRC_BURST_64 | CSDP_SRC_PACKED;
> + else if (port_window / 32)
> + d->csdp = CSDP_SRC_BURST_32 | CSDP_SRC_PACKED;
> + else if (port_window / 16)
> + d->csdp = CSDP_SRC_BURST_16 | CSDP_SRC_PACKED;
Why these divisions? Wouldn't >= be more suitable here? Do they even
make sense here?
> + } else {
> + d->ccr |= CCR_SRC_AMODE_CONSTANT;
> + }
> } else {
> - d->ccr |= CCR_DST_AMODE_CONSTANT | CCR_SRC_AMODE_POSTINC;
> d->csdp = CSDP_SRC_BURST_64 | CSDP_SRC_PACKED;
> +
> + d->ccr |= CCR_SRC_AMODE_POSTINC;
> + if (port_window) {
> + d->ccr |= CCR_DST_AMODE_DBLIDX;
> +
> + if (port_window / 64)
> + d->csdp = CSDP_DST_BURST_64 | CSDP_DST_PACKED;
> + else if (port_window / 32)
> + d->csdp = CSDP_DST_BURST_32 | CSDP_DST_PACKED;
> + else if (port_window / 16)
> + d->csdp = CSDP_DST_BURST_16 | CSDP_DST_PACKED;
Ditto.
> + } else {
> + d->ccr |= CCR_DST_AMODE_CONSTANT;
> + }
> }
>
> d->cicr = CICR_DROP_IE | CICR_BLOCK_IE;
> @@ -945,6 +979,9 @@ static struct dma_async_tx_descriptor
> *omap_dma_prep_slave_sg(
> d->ccr |= CCR_TRIGGER_SRC;
>
> d->cicr |= CICR_MISALIGNED_ERR_IE | CICR_TRANS_ERR_IE;
> +
> + if (port_window)
> + d->csdp |= CSDP_WRITE_LAST_NON_POSTED;
> }
> if (od->plat->errata & DMA_ERRATA_PARALLEL_CHANNELS)
> d->clnk_ctrl = c->dma_ch;
> @@ -970,6 +1007,10 @@ static struct dma_async_tx_descriptor
> *omap_dma_prep_slave_sg(
> osg->addr = sg_dma_address(sgent);
> osg->en = en;
> osg->fn = sg_dma_len(sgent) / frame_bytes;
> + if (port_window && dir == DMA_MEM_TO_DEV) {
> + osg->ei = 1;
> + osg->fi = (-1) * (port_window - 1);
Same as above.
--
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