> -----Original Message----- > From: One Thousand Gnomes [mailto:gno...@lxorguk.ukuu.org.uk] > Sent: 09 November 2016 13:55 > To: Arnd Bergmann > Cc: Mark Rutland; Yuanzhichang; catalin.mari...@arm.com; > will.dea...@arm.com; robh...@kernel.org; bhelg...@google.com; > o...@lixom.net; linux-arm-ker...@lists.infradead.org; > lorenzo.pieral...@arm.com; linux-kernel@vger.kernel.org; Linuxarm; > devicet...@vger.kernel.org; linux-...@vger.kernel.org; linux- > ser...@vger.kernel.org; miny...@acm.org; b...@kernel.crashing.org; > liviu.du...@arm.com; zourongr...@gmail.com; John Garry; Gabriele > Paoloni; zhichang.yua...@gmail.com; kant...@163.com; xuwei (O); > marc.zyng...@arm.com > Subject: Re: [PATCH V5 2/3] ARM64 LPC: Add missing range exception for > special ISA > > > I think it is a relatively safe assumption that there is only one > > ISA bridge. A lot of old drivers hardcode PIO or memory addresses > > It's not a safe assumption for x86 at least. There are a few systems > with > multiple ISA busses particularly older laptops with a docking station.
Mmmm right...now the point is that this kind of special devices appearing as a special ISA bus will probably never appear on x86 platforms (I guess). So maybe it is a safe assumption because of this...? Thanks Gab > > > when talking to an ISA device, so having multiple instances is > > already problematic. > > PCMCIA devices handle it themselves so are ok. I'm not clear how the > dual > PIIX4 configuration used in the older IBM laptop docks actually worked > so > I assume the transaction went out of both bridges and providing one of > them responded the other kept silent as you simply stuffed the card > into > the dock and it worked. > > Alan
