On Fri, May 29, 2020 at 01:23:59AM +0300, Serge Semin wrote: > According to the DW APB DMAC data book the minimum burst transaction > length is 1 and it's true for any version of the controller since > isn't parametrised in the coreAssembler so can't be changed at the > IP-core synthesis stage. Let's initialise the min_burst member of the > DMA controller descriptor so the DMA clients could use it to properly > optimize the DMA requests. > @@ -1229,6 +1229,7 @@ int do_dma_probe(struct dw_dma_chip *chip) > dw->dma.device_issue_pending = dwc_issue_pending; > > /* DMA capabilities */ > + dw->dma.min_burst = 1; Perhaps then relaxed maximum, like dw->dma.max_burst = 256; (channels will update this) ? > dw->dma.src_addr_widths = DW_DMA_BUSWIDTHS; > dw->dma.dst_addr_widths = DW_DMA_BUSWIDTHS; > dw->dma.directions = BIT(DMA_DEV_TO_MEM) | BIT(DMA_MEM_TO_DEV) | > -- > 2.26.2 > -- With Best Regards, Andy Shevchenko