Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753597Ab2BVQgd (ORCPT ); Wed, 22 Feb 2012 11:36:33 -0500 Received: from mailout3.w1.samsung.com ([210.118.77.13]:15242 "EHLO mailout3.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751882Ab2BVQga (ORCPT ); Wed, 22 Feb 2012 11:36:30 -0500 MIME-version: 1.0 Content-transfer-encoding: 7BIT Content-type: text/plain; charset=us-ascii Date: Wed, 22 Feb 2012 17:36:25 +0100 From: Marek Szyprowski Subject: RE: [PATCHv22 14/16] X86: integrate CMA with DMA-mapping subsystem In-reply-to: <20120221161802.f6a28085.akpm@linux-foundation.org> To: "'Andrew Morton'" Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-media@vger.kernel.org, linux-mm@kvack.org, linaro-mm-sig@lists.linaro.org, "'Michal Nazarewicz'" , "'Kyungmin Park'" , "'Russell King'" , "'KAMEZAWA Hiroyuki'" , "'Daniel Walker'" , "'Mel Gorman'" , "'Arnd Bergmann'" , "'Jesse Barker'" , "'Jonathan Corbet'" , "'Shariq Hasnain'" , "'Chunsang Jeong'" , "'Dave Hansen'" , "'Benjamin Gaignard'" , "'Rob Clark'" , "'Ohad Ben-Cohen'" Message-id: <000101ccf180$1e5226b0$5af67410$%szyprowski@samsung.com> Organization: SPRC X-Mailer: Microsoft Office Outlook 12.0 Content-language: pl Thread-index: Aczw93NdR6imxbLiSjaf5A+h5crMwQAh1b0w References: <1329507036-24362-1-git-send-email-m.szyprowski@samsung.com> <1329507036-24362-15-git-send-email-m.szyprowski@samsung.com> <20120221161802.f6a28085.akpm@linux-foundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2094 Lines: 59 Hi Andrew, On Wednesday, February 22, 2012 1:18 AM Andrew Morton wrote: > > This patch adds support for CMA to dma-mapping subsystem for x86 > > architecture that uses common pci-dma/pci-nommu implementation. This > > allows to test CMA on KVM/QEMU and a lot of common x86 boxes. > > > > ... > > > > --- a/arch/x86/Kconfig > > +++ b/arch/x86/Kconfig > > @@ -31,6 +31,7 @@ config X86 > > select ARCH_WANT_OPTIONAL_GPIOLIB > > select ARCH_WANT_FRAME_POINTERS > > select HAVE_DMA_ATTRS > > + select HAVE_DMA_CONTIGUOUS if !SWIOTLB > > select HAVE_KRETPROBES > > select HAVE_OPTPROBES > > select HAVE_FTRACE_MCOUNT_RECORD > > I don't think it's compilable at all for x86_64, because that platform > selects SWIOTLB. Right, x86 support is very basic, mainly for being able to test it on standard configuration with QEmu. > After a while I got it to compile for i386. arm didn't go so well, > partly because arm allmodconfig is presently horked (something to do > with Kconfig not setting PHYS_OFFSET) and partly because arm defconfig > doesn't permit CMA to be set. Got bored, gave up. I think that all*config are broken on ARM. To enable CMA compilation, one need to select a subplatform based on ARMv6+ - for example one can start from arch/arm/configs/exynos4_defconfig and then use oldnoconfig. > The patchset collides pretty seriously with pending dma api changes and > pending arm changes in linux-next, so I didn't apply anything. This > will all need to be looked at, please. > > I'll make do with reading the patches for now ;) I've rebased the CMA patchset on top of next-20120222 kernel tree and I will send them soon as v23. I hope this will help getting them merged to your tree. If I should select different base for the patches, just let me know. Best regards -- Marek Szyprowski Samsung Poland R&D Center -- 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/