On Mon, Jan 08, 2018 at 05:25:01PM +0000, Appana Durga Kedareswara Rao wrote: > Hi, > > <Snip> > >> >> + 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 > > Address width is configurable parameter at the h/w level. > Since this IP is a soft IP user can create a design with either > 32-bit or 64-bit address configuration. and not both right? > Currently we are reading this configuration through device-tree (xlnx, addr-width property) > https://git.kernel.org/pub/scm/linux/kernel/git/vkoul/slave-dma.git/tree/Documentation/devicetree/bindings/dma/xilinx/xilinx_dma.txt#n19 > Based on the h/w configuration setting the dst_addr_widths/src_addr_widths variables in this patch. > Please let me know if you are still not clear with my explanation will explain in detail... > > Regards, > Kedar. > > > > >> 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 -- ~Vinod -- 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
