Subject: Re: Could I (ab)use bus (struct bus_type) for virtual Broadcom bus?
From: George Kashperko <george@znau.edu.ua>
To: =?UTF-8?Q?Rafa=C5=82_Mi=C5=82ecki?= <zajec5@gmail.com>
Cc: Hauke Mehrtens <hauke@hauke-m.de>,
	Russell King <rmk@arm.linux.org.uk>,
	Arnd Bergmann <arnd@arndb.de>, linux-kernel@vger.kernel.org,
	linux-wireless@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	Arend van Spriel <arend@broadcom.com>,
	Jonas Gorski <jonas.gorski@gmail.com>,
	b43-dev@lists.infradead.org, Greg KH <greg@kroah.com>,
	Andy Botting <andy@andybotting.com>,
	Larry Finger <Larry.Finger@lwfinger.net>
In-Reply-To: <BANLkTi=16i+D8frz3X2f+JDtp4hbJKLL3A@mail.gmail.com>
References: <BANLkTim7Uj2tsgFngWhUqFK_hk3Leg+sQA@mail.gmail.com>
	 <1302781431.21145.6.camel@dev.znau.edu.ua>
	 <BANLkTinvpt5vs+rXd3WN-a2JpGtTV+=Gyg@mail.gmail.com>
	 <4DA6E9BD.3090404@hauke-m.de>
	 <BANLkTinu+Q367oqQPiUehPcbMs-SBxbwFg@mail.gmail.com>
	 <1302786900.21965.52.camel@dev.znau.edu.ua>
	 <BANLkTimM8=-pX+Ea8Eyp4XyvP1APbUof9w@mail.gmail.com>
	 <1302892585.30441.12.camel@dev.znau.edu.ua>
	 <BANLkTi=16i+D8frz3X2f+JDtp4hbJKLL3A@mail.gmail.com>
Content-Type: text/plain; charset=utf-8
Date: Fri, 15 Apr 2011 22:50:10 +0300
Message-Id: <1302897010.30441.42.camel@dev.znau.edu.ua>
Mime-Version: 1.0
Sender: linux-wireless-owner@vger.kernel.org


> W dniu 15 kwietnia 2011 20:36 użytkownik George Kashperko
> <george@znau.edu.ua> napisał:
> >> >> 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.
> >>
> >
> > Played around amba registers on bcm4716. For all amba cores present
> > (under all I mean broadcom ip core agents, oob router core, erom core,
> > and other I-dont-know-what-for cores present at 0x18100000). All those
> > feature AMBA_CID (0xb105f00d) as PrimeCell ID, and slightly different
> > PrimeCell PeripheralIDs:
> > * vendor 0xBB, part_number 0x368 for broadcom cores' agents;
> > * vendor 0xBB, part_number 0x367 for OOB router core (don't ask me wth
> > is this please);
> > * vendor 0xBB, part_number 0x366 for EROM core;
> >
> > ARM vendor id is 0x41. Might 0xBB is Broadcom vendor id but I've found
> > no evidence for that with google.
> 
> Yeah, as I suspected, everything except Broadcom specific cores
> matches AMBA standards quite nicely. Still, I don't see anything in it
> we could use for driver.
> 
> Let's wait for Russell and Arnd to comment.
> 

Btw, googling for PL366, PL367, PL368 gives nothing relevant except one
reference to "NIC-301 Interconnect Device Management (PL368)" which is
restricted to arm partners. Think it have something to do with that
magic "DMP - Device Management Plugin" Broadcom guys mentioned earlier.
Might those 0xBB/0x368 cores are produced with that "plugin".

Have nice day,
George