From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: Re: [PATCH 1/2] asm-generic/io.h: provide default ioremap/iounmap for !HAS_IOMEM Date: Wed, 30 Mar 2016 15:51:19 +0200 Message-ID: <5372571.zc5TeOVXyF@wuerfel> References: <1459275781-3863-1-git-send-email-robh@kernel.org> <6282729.XLLXSxbzQJ@wuerfel> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7Bit Return-path: Received: from mout.kundenserver.de ([217.72.192.73]:51906 "EHLO mout.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752921AbcC3Nvj (ORCPT ); Wed, 30 Mar 2016 09:51:39 -0400 In-Reply-To: Sender: linux-arch-owner@vger.kernel.org List-ID: To: Rob Herring Cc: Richard Weinberger , Lee Jones , "linux-kernel@vger.kernel.org" , "linux-arch@vger.kernel.org" , user-mode-linux-devel@lists.sourceforge.net On Wednesday 30 March 2016 08:29:45 Rob Herring wrote: > On Wed, Mar 30, 2016 at 5:03 AM, Arnd Bergmann wrote: > > On Wednesday 30 March 2016 10:13:53 Richard Weinberger wrote: > >> > >> I fully understand your point of view. COMPILE_TEST is a monster that > >> can do the heavy lifting for you, but monsters also have claws and fangs. > >> > >> Having COMPILE_TEST having depend on !UML works for me. But don't > >> we have other archs without io mem? At least a few years ago while > >> porting nandsim to UML I found s390 that lacks of io mem too. > > > > s390 gained IOMEM support when they started having PCI attachments. > > I'm confused how s390 defines HAS_IOMEM and includes it from lib/Kconfig though. Kconfig can define the same symbol multiple times, which is really confusing. I only checked for NO_IOMEM, which s390 no longer defines, but I have not checked what actually happens in case of two conflicting definitions, where the one lib/Kconfig defaults to 'y' and the one in arch/s390 defaults to CONFIG_PCI. Arnd