diff options
| author | Daniel Mack <zonque@gmail.com> | 2013-08-10 18:52:22 +0200 |
|---|---|---|
| committer | Vinod Koul <vinod.koul@intel.com> | 2013-08-14 13:55:16 +0530 |
| commit | 6fc4573c4e17eb57f6e1a20992dcf0b6a105afdb (patch) | |
| tree | 4a3e10a868da8fdff40bd68a42e0aa8346e42905 /drivers/dma/mmp_pdma.c | |
| parent | 8fd6aac3a8234d4ffd0ea514ba2aba9488888a36 (diff) | |
| download | linux-6fc4573c4e17eb57f6e1a20992dcf0b6a105afdb.tar.bz2 | |
dma: mmp_pdma: add support for byte-aligned transfers
The PXA DMA controller has a DALGN register which allows for
byte-aligned DMA transfers. Use it in case any of the transfer
descriptors is not aligned to a mask of ~0x7.
Signed-off-by: Daniel Mack <zonque@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Diffstat (limited to 'drivers/dma/mmp_pdma.c')
| -rw-r--r-- | drivers/dma/mmp_pdma.c | 17 |
1 files changed, 16 insertions, 1 deletions
diff --git a/drivers/dma/mmp_pdma.c b/drivers/dma/mmp_pdma.c index b426e55f8316..dba9fe9cbbbe 100644 --- a/drivers/dma/mmp_pdma.c +++ b/drivers/dma/mmp_pdma.c @@ -109,6 +109,7 @@ struct mmp_pdma_chan { struct list_head chain_pending; /* Link descriptors queue for pending */ struct list_head chain_running; /* Link descriptors queue for running */ bool idle; /* channel statue machine */ + bool byte_align; struct dma_pool *desc_pool; /* Descriptors pool */ }; @@ -142,7 +143,7 @@ static void set_desc(struct mmp_pdma_phy *phy, dma_addr_t addr) static void enable_chan(struct mmp_pdma_phy *phy) { - u32 reg; + u32 reg, dalgn; if (!phy->vchan) return; @@ -150,6 +151,13 @@ static void enable_chan(struct mmp_pdma_phy *phy) reg = DRCMR(phy->vchan->drcmr); writel(DRCMR_MAPVLD | phy->idx, phy->base + reg); + dalgn = readl(phy->base + DALGN); + if (phy->vchan->byte_align) + dalgn |= 1 << phy->idx; + else + dalgn &= ~(1 << phy->idx); + writel(dalgn, phy->base + DALGN); + reg = (phy->idx << 2) + DCSR; writel(readl(phy->base + reg) | DCSR_RUN, phy->base + reg); @@ -455,6 +463,7 @@ mmp_pdma_prep_memcpy(struct dma_chan *dchan, return NULL; chan = to_mmp_pdma_chan(dchan); + chan->byte_align = false; if (!chan->dir) { chan->dir = DMA_MEM_TO_MEM; @@ -471,6 +480,8 @@ mmp_pdma_prep_memcpy(struct dma_chan *dchan, } copy = min_t(size_t, len, PDMA_MAX_DESC_BYTES); + if (dma_src & 0x7 || dma_dst & 0x7) + chan->byte_align = true; new->desc.dcmd = chan->dcmd | (DCMD_LENGTH & copy); new->desc.dsadr = dma_src; @@ -530,12 +541,16 @@ mmp_pdma_prep_slave_sg(struct dma_chan *dchan, struct scatterlist *sgl, if ((sgl == NULL) || (sg_len == 0)) return NULL; + chan->byte_align = false; + for_each_sg(sgl, sg, sg_len, i) { addr = sg_dma_address(sg); avail = sg_dma_len(sgl); do { len = min_t(size_t, avail, PDMA_MAX_DESC_BYTES); + if (addr & 0x7) + chan->byte_align = true; /* allocate and populate the descriptor */ new = mmp_pdma_alloc_descriptor(chan); |