diff options
Diffstat (limited to 'drivers/dma')
| -rw-r--r-- | drivers/dma/at_xdmac.c | 63 |
1 files changed, 32 insertions, 31 deletions
diff --git a/drivers/dma/at_xdmac.c b/drivers/dma/at_xdmac.c index 2d03951..cbeadee 100644 --- a/drivers/dma/at_xdmac.c +++ b/drivers/dma/at_xdmac.c @@ -749,6 +749,35 @@ at_xdmac_prep_dma_cyclic(struct dma_chan *chan, dma_addr_t buf_addr, return &first->tx_dma_desc; } +static inline u32 at_xdmac_align_width(struct dma_chan *chan, dma_addr_t addr) +{ + u32 width; + + /* + * Check address alignment to select the greater data width we + * can use. + * + * Some XDMAC implementations don't provide dword transfer, in + * this case selecting dword has the same behavior as + * selecting word transfers. + */ + if (!(addr & 7)) { + width = AT_XDMAC_CC_DWIDTH_DWORD; + dev_dbg(chan2dev(chan), "%s: dwidth: double word\n", __func__); + } else if (!(addr & 3)) { + width = AT_XDMAC_CC_DWIDTH_WORD; + dev_dbg(chan2dev(chan), "%s: dwidth: word\n", __func__); + } else if (!(addr & 1)) { + width = AT_XDMAC_CC_DWIDTH_HALFWORD; + dev_dbg(chan2dev(chan), "%s: dwidth: half word\n", __func__); + } else { + width = AT_XDMAC_CC_DWIDTH_BYTE; + dev_dbg(chan2dev(chan), "%s: dwidth: byte\n", __func__); + } + + return width; +} + static struct dma_async_tx_descriptor * at_xdmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, size_t len, unsigned long flags) @@ -779,24 +808,7 @@ at_xdmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, if (unlikely(!len)) return NULL; - /* - * Check address alignment to select the greater data width we can use. - * Some XDMAC implementations don't provide dword transfer, in this - * case selecting dword has the same behavior as selecting word transfers. - */ - if (!((src_addr | dst_addr) & 7)) { - dwidth = AT_XDMAC_CC_DWIDTH_DWORD; - dev_dbg(chan2dev(chan), "%s: dwidth: double word\n", __func__); - } else if (!((src_addr | dst_addr) & 3)) { - dwidth = AT_XDMAC_CC_DWIDTH_WORD; - dev_dbg(chan2dev(chan), "%s: dwidth: word\n", __func__); - } else if (!((src_addr | dst_addr) & 1)) { - dwidth = AT_XDMAC_CC_DWIDTH_HALFWORD; - dev_dbg(chan2dev(chan), "%s: dwidth: half word\n", __func__); - } else { - dwidth = AT_XDMAC_CC_DWIDTH_BYTE; - dev_dbg(chan2dev(chan), "%s: dwidth: byte\n", __func__); - } + dwidth = at_xdmac_align_width(chan, src_addr | dst_addr); /* Prepare descriptors. */ while (remaining_size) { @@ -826,19 +838,8 @@ at_xdmac_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, dev_dbg(chan2dev(chan), "%s: xfer_size=%zu\n", __func__, xfer_size); /* Check remaining length and change data width if needed. */ - if (!((src_addr | dst_addr | xfer_size) & 7)) { - dwidth = AT_XDMAC_CC_DWIDTH_DWORD; - dev_dbg(chan2dev(chan), "%s: dwidth: double word\n", __func__); - } else if (!((src_addr | dst_addr | xfer_size) & 3)) { - dwidth = AT_XDMAC_CC_DWIDTH_WORD; - dev_dbg(chan2dev(chan), "%s: dwidth: word\n", __func__); - } else if (!((src_addr | dst_addr | xfer_size) & 1)) { - dwidth = AT_XDMAC_CC_DWIDTH_HALFWORD; - dev_dbg(chan2dev(chan), "%s: dwidth: half word\n", __func__); - } else if ((src_addr | dst_addr | xfer_size) & 1) { - dwidth = AT_XDMAC_CC_DWIDTH_BYTE; - dev_dbg(chan2dev(chan), "%s: dwidth: byte\n", __func__); - } + dwidth = at_xdmac_align_width(chan, + src_addr | dst_addr | xfer_size); chan_cc |= AT_XDMAC_CC_DWIDTH(dwidth); ublen = xfer_size >> dwidth; |