On 26/10/16 08:39, Mark L. wrote: Hi Mark,
> I have a doubt I would like to clear. > When you buy a Allwinner H3, one doesn't have to mess with the AMBA > specification, right? > We just use the H3 interface we got (clock, secure memory) and that is it? > > Isn't this specification for hardware (Chip) makers only? Even a PCB maker > shouldn't be too concerned by it as well (except to connect the right pins > with the right traces) Yes, usually on this side of the SoC you don't have to care too much about AMBA, as it is an on-chip interconnect only. So there are no "AMBA pins" exposed on the package, for instance. Sometime you see AMBA terms "shine through" in the documentation, for instance AHB and APB are AMBA names, Allwinner named the respective clocks this way. Also you have to be aware that this is a bus system external to the *core* (but not the SoC), so the usual concerns about buses apply here: delay, arbitration, possible aborts, cache coherency and so on. So writing something to an MMIO device is not guaranteed to land immediately and in every case there, for instance. But this is not really AMBA specific, but applies to other peripheral buses like PCI as well. But you are right that from a software point of view (and even as a PCB designer) you should not need the AMBA specification to get yourself going. Cheers, Andre. -- You received this message because you are subscribed to the Google Groups "linux-sunxi" group. To unsubscribe from this group and stop receiving emails from it, send an email to linux-sunxi+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
