From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chen Gang Subject: Re: [PATCH] drivers/ptp/Kconfig: add "depends on HAS_IOMEM" for 'PTP_1588_CLOCK_PCH' Date: Mon, 01 Jul 2013 15:47:42 +0800 Message-ID: <51D1341E.6090908@asianux.com> References: <51CB8CB7.6010006@asianux.com> <20130628.212311.1348427834856668120.davem@davemloft.net> <51D0DCB5.5060106@asianux.com> <51D11661.7040604@nod.at> <51D11D14.8000706@asianux.com> <51D122F0.1000204@nod.at> <51D12545.4000108@asianux.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Cc: Richard Weinberger , David Miller , Richard Cochran , "netdev@vger.kernel.org" To: Geert Uytterhoeven Return-path: Received: from intranet.asianux.com ([58.214.24.6]:25495 "EHLO intranet.asianux.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752969Ab3GAHse (ORCPT ); Mon, 1 Jul 2013 03:48:34 -0400 In-Reply-To: Sender: netdev-owner@vger.kernel.org List-ID: On 07/01/2013 03:32 PM, Geert Uytterhoeven wrote: > On Mon, Jul 1, 2013 at 8:44 AM, Chen Gang wrote: >> > On 07/01/2013 02:34 PM, Richard Weinberger wrote: >>>> >>> config COMPILE_TEST >>>>> >>> > bool "Compile also drivers which will not load" >>>>> >>> > default n >>>>> >>> > help >>>>> >>> > Some drivers can be compiled on a different platform than they are >>>>> >>> > intended to be run on. Despite they cannot be loaded there (or even >>>>> >>> > when they load they cannot be used due to missing HW support), >>>>> >>> > developers still, opposing to distributors, might want to build such >>>>> >>> > drivers to compile-test them. >>>>> >>> > >>>>> >>> > If you are a developer and want to build everything available, say Y >>>>> >>> > here. If you are a user/distributor, say N here to exclude useless >>>>> >>> > drivers to be distributed. >>>>> >>> > >>>>> >>> > I guess, 'COMPILE_TEST' is really useful for UML. >>> >> No. >>> >> >>> >> We have explained you more than once what the deal and why UML does not >>> >> have ioremap() and friends. >> > >> > This time, it is not for UML, it is for 'COMPILE_TEST': the >> > 'asm-generic' whether need consider it. > COMPILE_TEST is only meant to be used as a dependency in Kconfig files, > to make drivers that cannot work due to missing hardware invisible when > configuring your kernel. > Why "Despite they cannot be loaded there (or even when they load they cannot be used due to missing HW support)" ? > There should be no #ifdefs in actual code that check for (the lack of) > CONFIG_COMPILE_TEST. In ideal world, it should be no #ifdefs for all "CONFIG_*" in 'normal code'. But "asm-generic" are not belong to 'normal code', it is one of the main place to process "CONFIG_*". If the platforms need support 'COMPILE_TEST', the asm-generic is the main place for implementing it. So I think our focus is on "whether the platforms guys need support 'COMPILE_TEST" for modules guys". Thanks -- Chen Gang