Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754137AbXLKAG1 (ORCPT ); Mon, 10 Dec 2007 19:06:27 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752500AbXLKAGU (ORCPT ); Mon, 10 Dec 2007 19:06:20 -0500 Received: from ftp.linux-mips.org ([194.74.144.162]:50546 "EHLO ftp.linux-mips.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752440AbXLKAGT (ORCPT ); Mon, 10 Dec 2007 19:06:19 -0500 Date: Tue, 11 Dec 2007 00:05:37 +0000 From: Ralf Baechle To: Benjamin Herrenschmidt Cc: Alan Cox , Linus Torvalds , Yoichi Yuasa , Linux Kernel Mailing List , Greg KH , Bartlomiej Zolnierkiewicz Subject: Re: Please revert: PCI: fix IDE legacy mode resources Message-ID: <20071211000536.GA4067@linux-mips.org> References: <1197193794.6572.52.camel@pasglop> <20071209133812.2d305a02@the-village.bc.nu> <1197230609.6563.6.camel@pasglop> <20071209222335.70e52be3@the-village.bc.nu> <1197260962.6563.46.camel@pasglop> <20071210112050.0bd6ac28@the-village.bc.nu> <20071210134056.GC12913@linux-mips.org> <20071210150126.7cec9cbc@the-village.bc.nu> <20071210154732.GB19384@linux-mips.org> <1197319383.8692.18.camel@pasglop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1197319383.8692.18.camel@pasglop> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2163 Lines: 48 On Tue, Dec 11, 2007 at 07:43:03AM +1100, Benjamin Herrenschmidt wrote: > > > 0000:00:09.1 IDE interface: VIA Technologies, Inc. > > > VT82C586A/B/VT82C686/A/B/VT823x/A/C PIPC Bus Master IDE (rev 06) > > > (prog-if 8a [Master SecP PriP]) > > > Flags: bus master, fast Back2Back, medium devsel, latency 64 > > > I/O ports at 1820 [size=16] > > > > And that's lspci -v -b: > > > > > 0000:00:09.1 IDE interface: VIA Technologies, Inc. > > > VT82C586A/B/VT82C686/A/B/VT823x/A/C PIPC Bus Master IDE (rev 06) > > > (prog-if 8a [Master SecP PriP]) > > > Flags: bus master, fast Back2Back, medium devsel, latency 64 > > > I/O ports at 10001820 > > > > So the IDE controller already seems to be in native mode? > > > > No, native mode is 5 not A in the low 4 bits of progif. > > You need to be a bit careful about those VIA, I remember having issues > on Pegasos where we left it in legacy mode. It think the problem is that > even when switched, the IRQ routing might be done based on some other > setting in the chipset, possibly a strap. But that's nothing you can't > deal with an appropriate quirk in the arch code. > > Also, double check the level/edge setting of the interrupts as it can be > different between legacy and native (native is level low, legacy is > rising edge). > > I'm surprised however that one would use such a legacy southbridge on a > platform that can't issue low IO ports, that doesn't seem to make sense > to me ... there's a whole lot of things on this such as the 8259 PIC > etc.. that can only be addressed via low IOs, unless the ISA space can > be somewhat remapped ? The GT-64111 system controller doesn't provide any kind of mapping functionality that would help here. So legacy port addressing can only work by exploiting aliases due to incomplete decoding of legacy ioport addreses by the VT82C586 - but direct addressing is impossible. Ralf -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/