From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752818Ab3ABOkH (ORCPT ); Wed, 2 Jan 2013 09:40:07 -0500 Received: from mailout1.w1.samsung.com ([210.118.77.11]:31142 "EHLO mailout1.w1.samsung.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752677Ab3ABOkA (ORCPT ); Wed, 2 Jan 2013 09:40:00 -0500 MIME-version: 1.0 Content-transfer-encoding: 8BIT Content-type: text/plain; charset=UTF-8; format=flowed X-AuditID: cbfec7f5-b7fd76d000007247-84-50e446be8b55 Message-id: <50E446BB.7090609@samsung.com> Date: Wed, 02 Jan 2013 15:39:55 +0100 From: Marek Szyprowski User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:17.0) Gecko/17.0 Thunderbird/17.0 To: Geert Uytterhoeven Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, linux-media@vger.kernel.org, linux-m68k@vger.kernel.org Subject: Re: [PATCH/RFC 0/4] Re: dma_mmap_coherent / ARCH_HAS_DMA_MMAP_COHERENT References: <1356722614-18224-1-git-send-email-geert@linux-m68k.org> In-reply-to: <1356722614-18224-1-git-send-email-geert@linux-m68k.org> X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFprGLMWRmVeSWpSXmKPExsVy+t/xq7r73J4EGLw9oGbRsesri8XlXXPY LHa/v89o0bNhK6sDi8fnTXIBjFFcNimpOZllqUX6dglcGR2fOQqWKlRcbZzH2MD4V6KLkZND QsBE4uvcK0wQtpjEhXvr2boYuTiEBJYySjy7sZoVJMErICjxY/I9li5GDg5mAXmJI5eyQcLM AmYSj1rWMYPYQgLNTBLt//kgyrUk2h72sYHYLAKqEg0zfoONYRMwlOh62wUWFxXwlZj26xoT yEgRAV2JOT+ZIEaWSzzafR+sRFjAX2Lp9MOMEON7GSVmLPQGsTkFXCV+brnDNoFRYBaS42Yh HDcLyXELGJlXMYqmliYXFCel5xrpFSfmFpfmpesl5+duYoSE5dcdjEuPWR1iFOBgVOLhvaH/ OECINbGsuDL3EKMEB7OSCK8u15MAId6UxMqq1KL8+KLSnNTiQ4xMHJxSDYwRzAJHpU9bvb0e GX8ibqqdvoCe49L3i31tbAI9jLdWcUQ821KYvTbx5amj1cFLU46c1rumtPvYm10N0XK6Aeaa E8vvToh3ZlWQez35ro9e2c/4+Gv7vFY7fmV5e/JTb+GLFUsWezDtKvyv/vyKi0eE3QKD3n9N bLbLZ3rM8T6h/1jobMjaym9KLMUZiYZazEXFiQAXO1ilKQIAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, On 12/28/2012 8:23 PM, Geert Uytterhoeven wrote: > On Sun, Dec 16, 2012 at 5:03 PM, Geert Uytterhoeven > wrote: > > drivers/media/v4l2-core/videobuf2-dma-contig.c: In function ‘vb2_dc_mmap’: > > drivers/media/v4l2-core/videobuf2-dma-contig.c:204: error: implicit declaration of function ‘dma_mmap_coherent’ > > drivers/media/v4l2-core/videobuf2-dma-contig.c: In function ‘vb2_dc_get_base_sgt’: > > drivers/media/v4l2-core/videobuf2-dma-contig.c:387: error: implicit declaration of function ‘dma_get_sgtable’ > > make[6]: *** [drivers/media/v4l2-core/videobuf2-dma-contig.o] Error 1 > > make[6]: Target `__build' not remade because of errors. > > make[5]: *** [drivers/media/v4l2-core] Error 2 > > > > Both dma_mmap_coherent() and dma_get_sgtable() are defined in > > include/asm-generic/dma-mapping-common.h only, which is included by > > on alpha, arm, arm64, hexagon, ia64, microblaze, mips, > > openrisc, powerpc, s390, sh, sparc, tile, unicore32, x86. > > Should the remaining architectures include this, too? > > Should it be moved to ? > > I came up with an RFC-solution for this in [PATCH/RFC 3/4] > ("avr32/bfin/c6x/cris/frv/m68k/mn10300/parisc/xtensa: Add dummy get_dma_ops()") > and [PATCH/RFC 4/4] ("common: dma-mapping: Move dma_common_*() to > ") of this series. > > > Furthermore, there's ARCH_HAS_DMA_MMAP_COHERENT, which is defined > > by powerpc only: > > arch/powerpc/include/asm/dma-mapping.h:#define ARCH_HAS_DMA_MMAP_COHERENT > > > > and handled in some fishy way in sound/core/pcm_native.c: > > > > #ifndef ARCH_HAS_DMA_MMAP_COHERENT > > /* This should be defined / handled globally! */ > > #ifdef CONFIG_ARM > > #define ARCH_HAS_DMA_MMAP_COHERENT > > #endif > > #endif > > > > /* > > * mmap the DMA buffer on RAM > > */ > > int snd_pcm_lib_default_mmap(struct snd_pcm_substream *substream, > > struct vm_area_struct *area) > > { > > area->vm_flags |= VM_DONTEXPAND | VM_DONTDUMP; > > #ifdef ARCH_HAS_DMA_MMAP_COHERENT > > if (!substream->ops->page && > > substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV) > > return dma_mmap_coherent(substream->dma_buffer.dev.dev, > > area, > > substream->runtime->dma_area, > > substream->runtime->dma_addr, > > area->vm_end - area->vm_start); > > #elif defined(CONFIG_MIPS) && defined(CONFIG_DMA_NONCOHERENT) > > if (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV && > > !plat_device_is_coherent(substream->dma_buffer.dev.dev)) > > area->vm_page_prot = pgprot_noncached(area->vm_page_prot); > > #endif /* ARCH_HAS_DMA_MMAP_COHERENT */ > > /* mmap with fault handler */ > > area->vm_ops = &snd_pcm_vm_ops_data_fault; > > return 0; > > } > > EXPORT_SYMBOL_GPL(snd_pcm_lib_default_mmap); > > > > What's up here? > > Probably an easy solution here is to kill ARCH_HAS_DMA_MMAP_COHERENT and > change the code to > > #if defined(CONFIG_MIPS) && defined(CONFIG_DMA_NONCOHERENT) > if (substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV && > !plat_device_is_coherent(substream->dma_buffer.dev.dev)) > area->vm_page_prot = pgprot_noncached(area->vm_page_prot); > #else > if (!substream->ops->page && > substream->dma_buffer.dev.type == SNDRV_DMA_TYPE_DEV) > return dma_mmap_coherent(substream->dma_buffer.dev.dev, > area, > substream->runtime->dma_area, > substream->runtime->dma_addr, > area->vm_end - area->vm_start); > #endif > > but obviously I don't like the test for CONFIG_MIPS in generic code... I think that the best way of handling it would be to move this code to MIPS specific dma_mmap_coherent() implementation. Best regards -- Marek Szyprowski Samsung Poland R&D Center