Hi, >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? Yes not both at the same time... Axi dma controller can be configured for either 32-bit or 64-bit address... Regards, Kedar. > >> 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/tr >> ee/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 -- 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
