From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Return-Path: MIME-Version: 1.0 In-Reply-To: <2695922.yyinjvNuJK@wuerfel> References: <20170128204839.18330-1-linus.walleij@linaro.org> <20170128204839.18330-2-linus.walleij@linaro.org> <2695922.yyinjvNuJK@wuerfel> From: Linus Walleij Date: Sat, 4 Feb 2017 19:43:15 +0100 Message-ID: Subject: Re: [PATCH 2/4] PCI: add driver for Cortina Gemini Host Bridge To: Arnd Bergmann List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: openwrt-devel@openwrt.org, Florian Fainelli , Paulius Zaleckas , linux-pci , Hans Ulli Kroll , Bjorn Helgaas , Janos Laube , "linux-arm-kernel@lists.infradead.org" Content-Type: text/plain; charset="us-ascii" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+bjorn=helgaas.com@lists.infradead.org List-ID: On Wed, Feb 1, 2017 at 12:11 PM, Arnd Bergmann wrote: > On Saturday, January 28, 2017 9:48:37 PM CET Linus Walleij wrote: >> + /* No clue what these do */ >> + pcibios_min_io = 0x100; >> + pcibios_min_mem = 0; > > Don't touch these OK I have a clue why this is there now, atleast the first one. The first 0x100 in the IOspace is actually configuration registers for the bridge. That is why we have this: reg = <0x50000000 0x100>; (...) /* PCI ranges mappings */ ranges = /* 1MiB I/O space 0x50000000-0x500fffff */ <0x01000000 0 0 0x50000000 0 0x00100000>, This is in all the vendor code I have located too. So the pcibios_min_io is manipulated to avoid touching that sensitive area. But I also see that arch/arm/mm/iomap.c sets it to 0x1000, according to the commit because you said it's the only valid value :D I tried setting the IO range to <0x50000100 0x000FFF00> instead of <0x50000000 0x00100000> but predictably that doesn't work. Maybe it should, I don't know really. Yours, Linus Walleij _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel