diff options
Diffstat (limited to 'drivers/dma/at_xdmac.c')
| -rw-r--r-- | drivers/dma/at_xdmac.c | 209 |
1 files changed, 186 insertions, 23 deletions
diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c index cf1213de7865..a165b4bfd330 100644 --- a/drivers/dma/at_xdmac.c +++ b/drivers/dma/at_xdmac.c @@ -359,18 +359,19 @@ static void at_xdmac_start_xfer(struct at_xdmac_chan *atchan, * descriptor view 2 since some fields of the configuration register * depend on transfer size and src/dest addresses. */ - if (at_xdmac_chan_is_cyclic(atchan)) { + if (at_xdmac_chan_is_cyclic(atchan)) reg = AT_XDMAC_CNDC_NDVIEW_NDV1; - at_xdmac_chan_write(atchan, AT_XDMAC_CC, first->lld.mbr_cfg); - } else if (first->lld.mbr_ubc & AT_XDMAC_MBR_UBC_NDV3) { + else if (first->lld.mbr_ubc & AT_XDMAC_MBR_UBC_NDV3) reg = AT_XDMAC_CNDC_NDVIEW_NDV3; - } else { - /* - * No need to write AT_XDMAC_CC reg, it will be done when the - * descriptor is fecthed. - */ + else reg = AT_XDMAC_CNDC_NDVIEW_NDV2; - } + /* + * Even if the register will be updated from the configuration in the + * descriptor when using view 2 or higher, the PROT bit won't be set + * properly. This bit can be modified only by using the channel + * configuration register. + */ + at_xdmac_chan_write(atchan, AT_XDMAC_CC, first->lld.mbr_cfg); reg |= AT_XDMAC_CNDC_NDDUP | AT_XDMAC_CNDC_NDSUP @@ -624,12 +625,12 @@ at_xdmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, unsigned int sg_len, enum dma_transfer_direction direction, unsigned long flags, void *context) { - struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan); - struct at_xdmac_desc *first = NULL, *prev = NULL; - struct scatterlist *sg; - int i; - unsigned int xfer_size = 0; - unsigned long irqflags; + struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan); + struct at_xdmac_desc *first = NULL, *prev = NULL; + struct scatterlist *sg; + int i; + unsigned int xfer_size = 0; + unsigned long irqflags; struct dma_async_tx_descriptor *ret = NULL; if (!sgl) @@ -681,15 +682,16 @@ at_xdmac_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, desc->lld.mbr_sa = mem; desc->lld.mbr_da = atchan->sconfig.dst_addr; } - desc->lld.mbr_cfg = atchan->cfg; - dwidth = at_xdmac_get_dwidth(desc->lld.mbr_cfg); + dwidth = at_xdmac_get_dwidth(atchan->cfg); fixed_dwidth = IS_ALIGNED(len, 1 << dwidth) - ? at_xdmac_get_dwidth(desc->lld.mbr_cfg) + ? dwidth : AT_XDMAC_CC_DWIDTH_BYTE; desc->lld.mbr_ubc = AT_XDMAC_MBR_UBC_NDV2 /* next descriptor view */ | AT_XDMAC_MBR_UBC_NDEN /* next descriptor dst parameter update */ | AT_XDMAC_MBR_UBC_NSEN /* next descriptor src parameter update */ | (len >> fixed_dwidth); /* microblock length */ + desc->lld.mbr_cfg = (atchan->cfg & ~AT_XDMAC_CC_DWIDTH_MASK) | + AT_XDMAC_CC_DWIDTH(fixed_dwidth); 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); @@ -795,10 +797,7 @@ at_xdmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, list_add_tail(&desc->desc_node, &first->descs_list); } - prev->lld.mbr_nda = first->tx_dma_desc.phys; - dev_dbg(chan2dev(chan), - "%s: chain lld: prev=0x%p, mbr_nda=%pad\n", - __func__, prev, &prev->lld.mbr_nda); + at_xdmac_queue_desc(chan, prev, first); first->tx_dma_desc.flags = flags; first->xfer_size = buf_len; first->direction = direction; @@ -1133,7 +1132,7 @@ static struct at_xdmac_desc *at_xdmac_memset_create_desc(struct dma_chan *chan, * SAMA5D4x), so we can use the same interface for source and dest, * that solves the fact we don't know the direction. */ - u32 chan_cc = AT_XDMAC_CC_DAM_INCREMENTED_AM + u32 chan_cc = AT_XDMAC_CC_DAM_UBS_AM | AT_XDMAC_CC_SAM_INCREMENTED_AM | AT_XDMAC_CC_DIF(0) | AT_XDMAC_CC_SIF(0) @@ -1201,6 +1200,168 @@ at_xdmac_prep_dma_memset(struct dma_chan *chan, dma_addr_t dest, int value, return &desc->tx_dma_desc; } +static struct dma_async_tx_descriptor * +at_xdmac_prep_dma_memset_sg(struct dma_chan *chan, struct scatterlist *sgl, + unsigned int sg_len, int value, + unsigned long flags) +{ + struct at_xdmac_chan *atchan = to_at_xdmac_chan(chan); + struct at_xdmac_desc *desc, *pdesc = NULL, + *ppdesc = NULL, *first = NULL; + struct scatterlist *sg, *psg = NULL, *ppsg = NULL; + size_t stride = 0, pstride = 0, len = 0; + int i; + + if (!sgl) + return NULL; + + dev_dbg(chan2dev(chan), "%s: sg_len=%d, value=0x%x, flags=0x%lx\n", + __func__, sg_len, value, flags); + + /* Prepare descriptors. */ + for_each_sg(sgl, sg, sg_len, i) { + dev_dbg(chan2dev(chan), "%s: dest=0x%08x, len=%d, pattern=0x%x, flags=0x%lx\n", + __func__, sg_dma_address(sg), sg_dma_len(sg), + value, flags); + desc = at_xdmac_memset_create_desc(chan, atchan, + sg_dma_address(sg), + sg_dma_len(sg), + value); + if (!desc && first) + list_splice_init(&first->descs_list, + &atchan->free_descs_list); + + if (!first) + first = desc; + + /* Update our strides */ + pstride = stride; + if (psg) + stride = sg_dma_address(sg) - + (sg_dma_address(psg) + sg_dma_len(psg)); + + /* + * The scatterlist API gives us only the address and + * length of each elements. + * + * Unfortunately, we don't have the stride, which we + * will need to compute. + * + * That make us end up in a situation like this one: + * len stride len stride len + * +-------+ +-------+ +-------+ + * | N-2 | | N-1 | | N | + * +-------+ +-------+ +-------+ + * + * We need all these three elements (N-2, N-1 and N) + * to actually take the decision on whether we need to + * queue N-1 or reuse N-2. + * + * We will only consider N if it is the last element. + */ + if (ppdesc && pdesc) { + if ((stride == pstride) && + (sg_dma_len(ppsg) == sg_dma_len(psg))) { + dev_dbg(chan2dev(chan), + "%s: desc 0x%p can be merged with desc 0x%p\n", + __func__, pdesc, ppdesc); + + /* + * Increment the block count of the + * N-2 descriptor + */ + at_xdmac_increment_block_count(chan, ppdesc); + ppdesc->lld.mbr_dus = stride; + + /* + * Put back the N-1 descriptor in the + * free descriptor list + */ + list_add_tail(&pdesc->desc_node, + &atchan->free_descs_list); + + /* + * Make our N-1 descriptor pointer + * point to the N-2 since they were + * actually merged. + */ + pdesc = ppdesc; + + /* + * Rule out the case where we don't have + * pstride computed yet (our second sg + * element) + * + * We also want to catch the case where there + * would be a negative stride, + */ + } else if (pstride || + sg_dma_address(sg) < sg_dma_address(psg)) { + /* + * Queue the N-1 descriptor after the + * N-2 + */ + at_xdmac_queue_desc(chan, ppdesc, pdesc); + + /* + * Add the N-1 descriptor to the list + * of the descriptors used for this + * transfer + */ + list_add_tail(&desc->desc_node, + &first->descs_list); + dev_dbg(chan2dev(chan), + "%s: add desc 0x%p to descs_list 0x%p\n", + __func__, desc, first); + } + } + + /* + * If we are the last element, just see if we have the + * same size than the previous element. + * + * If so, we can merge it with the previous descriptor + * since we don't care about the stride anymore. + */ + if ((i == (sg_len - 1)) && + sg_dma_len(ppsg) == sg_dma_len(psg)) { + dev_dbg(chan2dev(chan), + "%s: desc 0x%p can be merged with desc 0x%p\n", + __func__, desc, pdesc); + + /* + * Increment the block count of the N-1 + * descriptor + */ + at_xdmac_increment_block_count(chan, pdesc); + pdesc->lld.mbr_dus = stride; + + /* + * Put back the N descriptor in the free + * descriptor list + */ + list_add_tail(&desc->desc_node, + &atchan->free_descs_list); + } + + /* Update our descriptors */ + ppdesc = pdesc; + pdesc = desc; + + /* Update our scatter pointers */ + ppsg = psg; + psg = sg; + + len += sg_dma_len(sg); + } + + first->tx_dma_desc.cookie = -EBUSY; + first->tx_dma_desc.flags = flags; + first->xfer_size = len; + + return &first->tx_dma_desc; +} + static enum dma_status at_xdmac_tx_status(struct dma_chan *chan, dma_cookie_t cookie, struct dma_tx_state *txstate) @@ -1734,6 +1895,7 @@ static int at_xdmac_probe(struct platform_device *pdev) dma_cap_set(DMA_INTERLEAVE, atxdmac->dma.cap_mask); dma_cap_set(DMA_MEMCPY, atxdmac->dma.cap_mask); dma_cap_set(DMA_MEMSET, atxdmac->dma.cap_mask); + dma_cap_set(DMA_MEMSET_SG, atxdmac->dma.cap_mask); dma_cap_set(DMA_SLAVE, atxdmac->dma.cap_mask); /* * Without DMA_PRIVATE the driver is not able to allocate more than @@ -1749,6 +1911,7 @@ static int at_xdmac_probe(struct platform_device *pdev) atxdmac->dma.device_prep_interleaved_dma = at_xdmac_prep_interleaved; atxdmac->dma.device_prep_dma_memcpy = at_xdmac_prep_dma_memcpy; atxdmac->dma.device_prep_dma_memset = at_xdmac_prep_dma_memset; + atxdmac->dma.device_prep_dma_memset_sg = at_xdmac_prep_dma_memset_sg; atxdmac->dma.device_prep_slave_sg = at_xdmac_prep_slave_sg; atxdmac->dma.device_config = at_xdmac_device_config; atxdmac->dma.device_pause = at_xdmac_device_pause; |