On Wed, Nov 26, 2014 at 05:22:28PM +0100, Ludovic Desroches wrote:
> Using the cc field of the descriptor simplifies the management of the channel
> configuration.
>
> Signed-off-by: Ludovic Desroches <ludovic.desroches@xxxxxxxxx>
> ---
> drivers/dma/at_xdmac.c | 33 +++++++++++++--------------------
> 1 file changed, 13 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c
> index bc4b018..94b714e 100644
> --- a/drivers/dma/at_xdmac.c
> +++ b/drivers/dma/at_xdmac.c
> @@ -200,6 +200,7 @@ struct at_xdmac_chan {
> u8 memif; /* Memory Interface */
> u32 per_src_addr;
> u32 per_dst_addr;
> + u32 save_cc;
> u32 save_cim;
> u32 save_cnda;
> u32 save_cndc;
> @@ -357,14 +358,7 @@ static void at_xdmac_start_xfer(struct at_xdmac_chan *atchan,
> */
> if (is_slave_direction(first->direction)) {
> reg = AT_XDMAC_CNDC_NDVIEW_NDV1;
> - if (first->direction == DMA_MEM_TO_DEV)
> - atchan->cfg[AT_XDMAC_CUR_CFG] =
> - atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG];
> - else
> - atchan->cfg[AT_XDMAC_CUR_CFG] =
> - atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG];
> - at_xdmac_chan_write(atchan, AT_XDMAC_CC,
> - atchan->cfg[AT_XDMAC_CUR_CFG]);
> + at_xdmac_chan_write(atchan, AT_XDMAC_CC, first->lld.mbr_cfg);
how is this related to adding cc field?
> } else {
> /*
> * No need to write AT_XDMAC_CC reg, it will be done when the
> @@ -568,7 +562,6 @@ at_xdmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
> struct at_xdmac_desc *first = NULL, *prev = NULL;
> struct scatterlist *sg;
> int i;
> - u32 cfg;
> unsigned int xfer_size = 0;
>
> if (!sgl)
> @@ -615,17 +608,17 @@ at_xdmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl,
> if (direction == DMA_DEV_TO_MEM) {
> desc->lld.mbr_sa = atchan->per_src_addr;
> desc->lld.mbr_da = mem;
> - cfg = atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG];
> + desc->lld.mbr_cfg = atchan->cfg[AT_XDMAC_DEV_TO_MEM_CFG];
> } else {
> desc->lld.mbr_sa = mem;
> desc->lld.mbr_da = atchan->per_dst_addr;
> - cfg = atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG];
> + desc->lld.mbr_cfg = atchan->cfg[AT_XDMAC_MEM_TO_DEV_CFG];
> }
> - desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV1 /* next descriptor view */
> - | AT_XDMAC_MBR_UBC_NDEN /* next descriptor dst parameter update */
> - | AT_XDMAC_MBR_UBC_NSEN /* next descriptor src parameter update */
> - | (i == sg_len - 1 ? 0 : AT_XDMAC_MBR_UBC_NDE) /* descriptor fetch */
> - | len / (1 << at_xdmac_get_dwidth(cfg)); /* microblock length */
> + desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV1 /* next descriptor view */
> + | AT_XDMAC_MBR_UBC_NDEN /* next descriptor dst parameter update */
> + | AT_XDMAC_MBR_UBC_NSEN /* next descriptor src parameter update */
> + | (i == sg_len - 1 ? 0 : AT_XDMAC_MBR_UBC_NDE) /* descriptor fetch */
> + | len / (1 << at_xdmac_get_dwidth(desc->lld.mbr_cfg)); /* microblock length */
> dev_dbg(chan2dev(chan),
> "%s: lld: mbr_sa=%pad, mbr_da=%pad, mbr_ubc=0x%08x\n",
> __func__, &desc->lld.mbr_sa, &desc->lld.mbr_da, desc->lld.mbr_ubc);
> @@ -889,7 +882,7 @@ at_xdmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
> enum dma_status ret;
> int residue;
> u32 cur_nda, mask, value;
> - u8 dwidth = at_xdmac_get_dwidth(atchan->cfg[AT_XDMAC_CUR_CFG]);
> + u8 dwidth = 0;
>
> ret = dma_cookie_status(chan, cookie, txstate);
> if (ret == DMA_COMPLETE)
> @@ -933,6 +926,7 @@ at_xdmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie,
> */
> descs_list = &desc->descs_list;
> list_for_each_entry_safe(desc, _desc, descs_list, desc_node) {
> + dwidth = at_xdmac_get_dwidth(desc->lld.mbr_cfg);
> residue -= (desc->lld.mbr_ubc & 0xffffff) << dwidth;
> if ((desc->lld.mbr_nda & 0xfffffffc) == cur_nda)
> break;
> @@ -1276,6 +1270,7 @@ static int atmel_xdmac_suspend(struct device *dev)
> list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
> struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan);
>
> + atchan->save_cc = at_xdmac_chan_read(atchan, AT_XDMAC_CC);
okay finally we end us using the new field, the code before that seems to
use existing lld.mbr_cfg, shouldnt this be another change explaining the
changes...
> if (at_xdmac_chan_is_cyclic(atchan)) {
> if (!at_xdmac_chan_is_paused(atchan))
> at_xdmac_device_pause(chan);
> @@ -1298,7 +1293,6 @@ static int atmel_xdmac_resume(struct device *dev)
> struct at_xdmac_chan *atchan;
> struct dma_chan *chan, *_chan;
> int i;
> - u32 cfg;
>
> clk_prepare_enable(atxdmac->clk);
>
> @@ -1313,8 +1307,7 @@ static int atmel_xdmac_resume(struct device *dev)
> at_xdmac_write(atxdmac, AT_XDMAC_GE, atxdmac->save_gs);
> list_for_each_entry_safe(chan, _chan, &atxdmac->dma.channels, device_node) {
> atchan = to_at_xdmac_chan(chan);
> - cfg = atchan->cfg[AT_XDMAC_CUR_CFG];
> - at_xdmac_chan_write(atchan, AT_XDMAC_CC, cfg);
> + at_xdmac_chan_write(atchan, AT_XDMAC_CC, atchan->save_cc);
only thing here wer are saving and restoring from save_cc. How does that
impact rest of the code above?
--
~Vinod
> if (at_xdmac_chan_is_cyclic(atchan)) {
> at_xdmac_chan_write(atchan, AT_XDMAC_CNDA, atchan->save_cnda);
> at_xdmac_chan_write(atchan, AT_XDMAC_CNDC, atchan->save_cndc);
> --
> 2.0.3
>
--
--
To unsubscribe from this list: send the line "unsubscribe dmaengine" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
