From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from moutng.kundenserver.de (moutng.kundenserver.de [212.227.126.179]) by ozlabs.org (Postfix) with ESMTP id 5096EDDE44 for ; Tue, 15 May 2007 09:39:51 +1000 (EST) From: Arnd Bergmann To: Benjamin Herrenschmidt Subject: Re: [RFC/PATCH] powerpc: Rewrite IO allocation & mapping on powerpc64 Date: Tue, 15 May 2007 01:39:41 +0200 References: <20070514075415.7999BDDEC8@ozlabs.org> <200705141637.19572.arnd@arndb.de> <1179176381.32247.98.camel@localhost.localdomain> In-Reply-To: <1179176381.32247.98.camel@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-15" Message-Id: <200705150139.41722.arnd@arndb.de> Cc: linuxppc-dev@ozlabs.org, Paul Mackerras , Anton Blanchard List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Monday 14 May 2007, Benjamin Herrenschmidt wrote: > > Can we make this depend on CONFIG_ISA? Most platforms don't actually want > > to build in ISA support. > > I'm not too sure about that. CONFIG_ISA means you have legacy devices or > ISA slots ? or both ? > Good point, it means ISA slots, so it's probably not the right option here: config ISA bool "Support for ISA-bus hardware" depends on PPC_PREP || PPC_CHRP select PPC_I8259 help Find out whether you have ISA slots on your motherboard. ISA is the name of a bus system, i.e. the way the CPU talks to the other stuff inside your box. If you have an Apple machine, say N here; if you have an IBM RS/6000 or pSeries machine or a PReP machine, say Y. If you have an embedded board, consult your board documentation. (side note: funny how it recommends to say Y for pSeries, but doesn't allow it ;-). Maybe we should instead build the new file depending on a new option and make the Kconfig read as config ISA def_bool y depends on PPC_PREP || PPC_CHRP select PPC_I8259 select LEGACY_IOPORT help This option is for actual ISA slots config LEGACY_IOPORT bool # maybe convert some of these into select statements default y if PPC_UDBG_16550 default y if SERIO_I8042 || PPC_I8259 || PARPORT_PC default y if MAPLE || MPC8641_HPCN default y if BLK_DEV_FD || PATA_LEGACY || IDE default y if VGA_CONSOLE || FB help This option enables the use of hardcoded PIO port numbers in device drivers. An interesting case is the frame buffer, most fb drivers use hardcoded register numbers for the VGA ports, without calling check_legacy_ioport, but rely on PCI probing to detect the presence of the device. Some IDE drivers do the same, but libata does not. Apparently, these are already broken if you plug such hardware into a secondary PCI bus. Arnd <><