On Fri, Apr 16, 2021 at 09:34:01AM -0400, Kyle Harding wrote: > My understanding is that the system with the SDIO hardware will write > packets directly to shared memory, and thus will be unavailable to be read > by the networking stack on the remote/virtual system. The SDIO hardware controller is off on the "device" side of a greybus connection, not on the host, so if any DMA needs to happen, that device side handles it. The SDIO hardware is not on the "host" side, perhaps you are getting confused as to how a greybus protocol is supposed to be used? Think of it as a SDIO device that is plugged into a system by a USB connection. The USB data traveling to the device doesn't care about SDIO dma stuff, as the whole SDIO controller hardware is in the USB device itself. You can think of greybus as just a way to tell a device "hey, here's some SDIO data, can you read/write it please?" The transport on which that message goes on does not matter, which is why you can do this over a network connection. hope this helps, greg k-h _______________________________________________ greybus-dev mailing list greybus-dev@xxxxxxxxxxxxxxxx https://lists.linaro.org/mailman/listinfo/greybus-dev
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