From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754222AbcB2Lre (ORCPT ); Mon, 29 Feb 2016 06:47:34 -0500 Received: from foss.arm.com ([217.140.101.70]:43748 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752497AbcB2Lrc (ORCPT ); Mon, 29 Feb 2016 06:47:32 -0500 Subject: Re: [PATCH 1/2] iommu/mediatek: select ARM_DMA_USE_IOMMU To: Arnd Bergmann References: <1456737553-496245-1-git-send-email-arnd@arndb.de> <2734684.OJWJHS6snX@wuerfel> <56D429F0.7010409@arm.com> <5357325.sBkT8ESvOS@wuerfel> Cc: Joerg Roedel , Joerg Roedel , linux-arm-kernel@lists.infradead.org, Yong Wu , iommu@lists.linux-foundation.org, linux-mediatek@lists.infradead.org, Matthias Brugger , linux-kernel@vger.kernel.org From: Robin Murphy Message-ID: <56D42FD0.8030302@arm.com> Date: Mon, 29 Feb 2016 11:47:28 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.5.1 MIME-Version: 1.0 In-Reply-To: <5357325.sBkT8ESvOS@wuerfel> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 29/02/16 11:29, Arnd Bergmann wrote: > On Monday 29 February 2016 11:22:24 Robin Murphy wrote: >>>>> diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig >>>>> index b325954cf8f8..ea0998921702 100644 >>>>> --- a/drivers/iommu/Kconfig >>>>> +++ b/drivers/iommu/Kconfig >>>>> @@ -341,6 +341,7 @@ config MTK_IOMMU >>>>> bool "MTK IOMMU Support" >>>>> depends on ARM || ARM64 >>>>> depends on ARCH_MEDIATEK || COMPILE_TEST >>>>> + select ARM_DMA_USE_IOMMU >>>> >>>> If going down this route, I'd be inclined to add an "if ARM" there, just >>>> for clarity. >>> >>> That would run into the NEED_SG_DMA_LENGTH problem on other architectures >>> that don't already set it, right? >> >> Sorry, I'm lost - wouldn't "depends on ARM || ARM64" make other >> architectures moot? arm64 already has NEED_SG_DMA_LENGTH=y by default. >> > > Nevermind, I didn't notice the dependency on the architecture. > > What is keeping us from having 'depends on ARM || ARM64 || COMPILE_TEST'? IIRC it got changed because the kbuild test robot was consistently blowing up due to missing definitions on things like parisc. Robin. > I assume it doesn't work yet, but it would be nice to get that done > at some point so we can take advantage of automated build testing like > coverity. > > Arnd >