On Thursday 08 October 2015 13:55:16 Rameshwar Prasad Sahu wrote: > The DMA engine supports memory copy, RAID5 XOR, RAID6 PQ, and other > computations. But the bandwidth of the entire DMA engine is shared > among all channels. This patch re-configures operations availability > such that one can achieve maximum performance for XOR and PQ > computation by removing the memory offload operations. > > Signed-off-by: Rameshwar Prasad Sahu <rsahu@xxxxxxx> > --- > drivers/dma/xgene-dma.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/dma/xgene-dma.c b/drivers/dma/xgene-dma.c > index 8d57b1b..2998fcb 100644 > --- a/drivers/dma/xgene-dma.c > +++ b/drivers/dma/xgene-dma.c > @@ -154,6 +154,7 @@ > #define XGENE_DMA_MAX_XOR_SRC 5 > #define XGENE_DMA_16K_BUFFER_LEN_CODE 0x0 > #define XGENE_DMA_INVALID_LEN_CODE 0x7800000000000000ULL > +#undef XGENE_DMA_MEMCPY_ENABLE > > /* X-Gene DMA descriptor error codes */ > #define ERR_DESC_AXI 0x01 > @@ -1707,7 +1708,9 @@ static void xgene_dma_set_caps(struct xgene_dma_chan *chan, > dma_cap_zero(dma_dev->cap_mask); > > /* Set DMA device capability */ > +#ifdef XGENE_DMA_MEMCPY_ENABLE > dma_cap_set(DMA_MEMCPY, dma_dev->cap_mask); > +#endif > dma_cap_set(DMA_SG, dma_dev->cap_mask); > > /* Basically here, the X-Gene SoC DMA engine channel 0 supports XOR I don't see what the #ifdef gains you here when the setting is hardcoded. Why not just remove that DMA_MEMCPY capability completely if you don't want to use it? Arnd -- 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
