diff options
Diffstat (limited to 'drivers/dma/sh/rcar-dmac.c')
| -rw-r--r-- | drivers/dma/sh/rcar-dmac.c | 52 |
1 files changed, 32 insertions, 20 deletions
diff --git a/drivers/dma/sh/rcar-dmac.c b/drivers/dma/sh/rcar-dmac.c index 48b22d5c8602..db41795fe42a 100644 --- a/drivers/dma/sh/rcar-dmac.c +++ b/drivers/dma/sh/rcar-dmac.c @@ -344,13 +344,19 @@ static void rcar_dmac_chan_start_xfer(struct rcar_dmac_chan *chan) rcar_dmac_chan_write(chan, RCAR_DMARS, chan->mid_rid); if (desc->hwdescs.use) { - struct rcar_dmac_xfer_chunk *chunk; + struct rcar_dmac_xfer_chunk *chunk = + list_first_entry(&desc->chunks, + struct rcar_dmac_xfer_chunk, node); dev_dbg(chan->chan.device->dev, "chan%u: queue desc %p: %u@%pad\n", chan->index, desc, desc->nchunks, &desc->hwdescs.dma); #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT + rcar_dmac_chan_write(chan, RCAR_DMAFIXSAR, + chunk->src_addr >> 32); + rcar_dmac_chan_write(chan, RCAR_DMAFIXDAR, + chunk->dst_addr >> 32); rcar_dmac_chan_write(chan, RCAR_DMAFIXDPBASE, desc->hwdescs.dma >> 32); #endif @@ -368,8 +374,6 @@ static void rcar_dmac_chan_start_xfer(struct rcar_dmac_chan *chan) * should. Initialize it manually with the destination address * of the first chunk. */ - chunk = list_first_entry(&desc->chunks, - struct rcar_dmac_xfer_chunk, node); rcar_dmac_chan_write(chan, RCAR_DMADAR, chunk->dst_addr & 0xffffffff); @@ -855,8 +859,12 @@ rcar_dmac_chan_prep_sg(struct rcar_dmac_chan *chan, struct scatterlist *sgl, unsigned int nchunks = 0; unsigned int max_chunk_size; unsigned int full_size = 0; - bool highmem = false; + bool cross_boundary = false; unsigned int i; +#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT + u32 high_dev_addr; + u32 high_mem_addr; +#endif desc = rcar_dmac_desc_get(chan); if (!desc) @@ -882,6 +890,16 @@ rcar_dmac_chan_prep_sg(struct rcar_dmac_chan *chan, struct scatterlist *sgl, full_size += len; +#ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT + if (i == 0) { + high_dev_addr = dev_addr >> 32; + high_mem_addr = mem_addr >> 32; + } + + if ((dev_addr >> 32 != high_dev_addr) || + (mem_addr >> 32 != high_mem_addr)) + cross_boundary = true; +#endif while (len) { unsigned int size = min(len, max_chunk_size); @@ -890,18 +908,14 @@ rcar_dmac_chan_prep_sg(struct rcar_dmac_chan *chan, struct scatterlist *sgl, * Prevent individual transfers from crossing 4GB * boundaries. */ - if (dev_addr >> 32 != (dev_addr + size - 1) >> 32) + if (dev_addr >> 32 != (dev_addr + size - 1) >> 32) { size = ALIGN(dev_addr, 1ULL << 32) - dev_addr; - if (mem_addr >> 32 != (mem_addr + size - 1) >> 32) + cross_boundary = true; + } + if (mem_addr >> 32 != (mem_addr + size - 1) >> 32) { size = ALIGN(mem_addr, 1ULL << 32) - mem_addr; - - /* - * Check if either of the source or destination address - * can't be expressed in 32 bits. If so we can't use - * hardware descriptor lists. - */ - if (dev_addr >> 32 || mem_addr >> 32) - highmem = true; + cross_boundary = true; + } #endif chunk = rcar_dmac_xfer_chunk_get(chan); @@ -943,13 +957,11 @@ rcar_dmac_chan_prep_sg(struct rcar_dmac_chan *chan, struct scatterlist *sgl, * Use hardware descriptor lists if possible when more than one chunk * needs to be transferred (otherwise they don't make much sense). * - * The highmem check currently covers the whole transfer. As an - * optimization we could use descriptor lists for consecutive lowmem - * chunks and direct manual mode for highmem chunks. Whether the - * performance improvement would be significant enough compared to the - * additional complexity remains to be investigated. + * Source/Destination address should be located in same 4GiB region + * in the 40bit address space when it uses Hardware descriptor, + * and cross_boundary is checking it. */ - desc->hwdescs.use = !highmem && nchunks > 1; + desc->hwdescs.use = !cross_boundary && nchunks > 1; if (desc->hwdescs.use) { if (rcar_dmac_fill_hwdesc(chan, desc) < 0) desc->hwdescs.use = false; |