[PATCH v2 1/4] dmaengine: xilinx_dma: populate dma caps properly
Vinod Koul
vinod.koul at intel.com
Mon Jan 8 09:06:55 PST 2018
On Mon, Jan 08, 2018 at 10:52:01AM +0000, Appana Durga Kedareswara Rao wrote:
> Hi Vinod,
>
> Thanks for the review....
> <Snip>
> >> @@ -2398,6 +2398,7 @@ static int xilinx_dma_chan_probe(struct
> >xilinx_dma_device *xdev,
> >> chan->direction = DMA_MEM_TO_DEV;
> >> chan->id = chan_id;
> >> chan->tdest = chan_id;
> >> + xdev->common.directions = BIT(DMA_MEM_TO_DEV);
> >>
> >> chan->ctrl_offset = XILINX_DMA_MM2S_CTRL_OFFSET;
> >> if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) { @@ -
> >2415,6
> >> +2416,7 @@ static int xilinx_dma_chan_probe(struct xilinx_dma_device *xdev,
> >> chan->direction = DMA_DEV_TO_MEM;
> >> chan->id = chan_id;
> >> chan->tdest = chan_id - xdev->nr_channels;
> >> + xdev->common.directions |= BIT(DMA_DEV_TO_MEM);
> >>
> >> chan->ctrl_offset = XILINX_DMA_S2MM_CTRL_OFFSET;
> >> if (xdev->dma_config->dmatype == XDMA_TYPE_VDMA) { @@ -
> >2629,6
> >> +2631,8 @@ static int xilinx_dma_probe(struct platform_device *pdev)
> >> dma_cap_set(DMA_PRIVATE, xdev->common.cap_mask);
> >> }
> >>
> >> + xdev->common.dst_addr_widths = BIT(addr_width / 8);
> >> + xdev->common.src_addr_widths = BIT(addr_width / 8);
> >
> >Do you not support trf of 1byte, 2 bytes, or 4 bytes wide transfers? What is value
> >of addr_width here typically? Usually controllers can support different widths and
> >this is a surprise that you support only one value
>
> Controller supports address width of 32 and 64.
Then this should have both 32 and 64 values here
> addr_width typical values are 32-bit or 64-bit .
> Here addr_width is device-tree parameter...
> my understanding of src_addr_widths/dst_addr_widths is, it is a bit mask of the
> address with in bytes that DMA supports, please correct if my understanding is wrong.
>
> Regards,
> Kedar.
>
> >
> >--
> >~Vinod
--
~Vinod
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