Messages in this thread | | | Date | Fri, 29 May 2020 13:25:15 +0300 | From | Andy Shevchenko <> | Subject | Re: [PATCH v4 09/11] dmaengine: dw: Initialize min_burst capability |
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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
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