Re: Could I (ab)use bus (struct bus_type) for virtual Broadcom bus?

From: RafaÅ MiÅecki
Date: Thu Apr 14 2011 - 09:45:36 EST


W dniu 14 kwietnia 2011 15:15 uÅytkownik George Kashperko
<george@xxxxxxxxxxx> napisaÅ:
>
>> W dniu 14 kwietnia 2011 14:34 uÅytkownik Hauke Mehrtens
>> <hauke@xxxxxxxxxx> napisaÅ:
>> > On 04/14/2011 02:04 PM, RafaÅ MiÅecki wrote:
>> >> Hauke: you were proposing integrating with drivers/amba. I really
>> >> expect you to comment on this, please tell us how do you see this now,
>> >> when we have better overview. I took your proposal seriously, you can
>> >> see the results above.
>> >
>> > I had no closer look at drivers/amba and this bus driver, I just saw
>> > that there was a discussion about drivers/amba and this implementation
>> > with no result. When the Bradcom cores are not directly connected to
>> > AMBA, but are using some sort of wrapper and there are no benefits in
>> > using drivers/amba, just leave it.
>> >
>> > As the implementation of the Braodcom AIX Bus contains some Broadcom
>> > extensions and there seams to be no normal AMBA device being connected
>> > to some Broadcom devices with this special interface number 3) "Broadcom
>> > specific bus (bcmai)" seams to the the best approach in my opinion.
>>
>> Thanks for commenting.
>>
>> Russell: you were asking:
>> > What does this do which the 'amba' bus support doesn't?
>> I believe I explained it well in this thread. Do you still think about
>> using amba/driver? Do you think we should use it?
>>
>> Arnd: I found you saying:
>> > I believe the one thing we really want from this driver is the bus
>> > scan code, which is not present in the amba bus implementation,
>> I explained how it works, I believe scanning (EPROM in this case) it
>> Broadcom specific, not really AMBA standard. How do you see it?
>>
> It might not Broadcom specific as EPROM core seems to be CoreLink one
> core and maybe is arm-developed. But it isn't documented publicly and we
> don't know yet if it is obligatory for all amba (or at least axi)
> interconnects or not.

Maybe EPROM is not Broadcom specific, but I suspect the content we
deal with in bcmai/axi is Broadcom specific. I didn't see any notes of
manuf/id/rev/class we deal with. So I guess everything *we* (out
driver) read from EPROM is Bcm specific.

--
RafaÅ
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