From patchwork Thu Sep 19 23:41:06 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Russell King X-Patchwork-Id: 2916191 Return-Path: X-Original-To: patchwork-linux-fbdev@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 83806BFF05 for ; Fri, 20 Sep 2013 11:04:42 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 6816820303 for ; Fri, 20 Sep 2013 11:04:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B7FE5202E8 for ; Fri, 20 Sep 2013 11:04:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754503Ab3ITLEg (ORCPT ); Fri, 20 Sep 2013 07:04:36 -0400 Received: from caramon.arm.linux.org.uk ([78.32.30.218]:39175 "EHLO caramon.arm.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754367Ab3ITLEf (ORCPT ); Fri, 20 Sep 2013 07:04:35 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=arm.linux.org.uk; s=caramon; h=Date:Sender:Message-Id:Subject:Cc:To:From:References:In-Reply-To; bh=NeBQFgVSYCReqYdngIOLQHAa8NherJ0rgyanZy+2j/0=; b=PQ7j79gIeO8gPYYjol1pnXTQT5pnKXO+rwHFxd9gak2+j8X4UOMq/y7Sfbc6M0sHMPPaR4EhKTIn0yZ52WJFfZWXuL+hTPC6crdb/4X4us4mRGOs3tS3TxHOE8VatvuTcpMpY77pu48mmVeI9OtJQYq3ux04KBCc9PzpH2OesuA=; Received: from e0022681537dd.dyn.arm.linux.org.uk ([2002:4e20:1eda:1:222:68ff:fe15:37dd]:59288 helo=rmk-PC.arm.linux.org.uk) by caramon.arm.linux.org.uk with esmtpsa (TLSv1:AES256-SHA:256) (Exim 4.76) (envelope-from ) id 1VMnqN-0001IZ-VP; Fri, 20 Sep 2013 00:41:08 +0100 Received: from rmk by rmk-PC.arm.linux.org.uk with local (Exim 4.76) (envelope-from ) id 1VMnqM-00026g-PP; Fri, 20 Sep 2013 00:41:06 +0100 In-Reply-To: <20130919212235.GD12758@n2100.arm.linux.org.uk> References: <20130919212235.GD12758@n2100.arm.linux.org.uk> From: Russell King To: alsa-devel@alsa-project.org, b43-dev@lists.infradead.org, devel@driverdev.osuosl.org, devicetree@vger.kernel.org, dri-devel@lists.freedesktop.org, e1000-devel@lists.sourceforge.net, linux-arm-kernel@lists.infradead.org, linux-crypto@vger.kernel.org, linux-doc@vger.kernel.org, linux-fbdev@vger.kernel.org, linux-ide@vger.kernel.org, linux-media@vger.kernel.org, linux-mmc@vger.kernel.org, linux-nvme@lists.infradead.org, linux-omap@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-samsung-soc@vger.kernel.org, linux-scsi@vger.kernel.org, linux-tegra@vger.kernel.org, linux-usb@vger.kernel.org, linux-wireless@vger.kernel.org, netdev@vger.kernel.org, Solarflare linux maintainers , uclinux-dist-devel@blackfin.uclinux.org Cc: Vinod Koul , Dan Williams , Jens Axboe Subject: [PATCH 48/51] ARM: 7795/1: mm: dma-mapping: Add dma_max_pfn(dev) helper function Message-Id: Date: Fri, 20 Sep 2013 00:41:06 +0100 Sender: linux-fbdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fbdev@vger.kernel.org X-Spam-Status: No, score=-3.9 required=5.0 tests=BAYES_00,DKIM_SIGNED, KHOP_BIG_TO_CC,RCVD_IN_DNSWL_HI,RP_MATCHES_RCVD,T_DKIM_INVALID, UNPARSEABLE_RELAY autolearn=ham version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Santosh Shilimkar Most of the kernel assumes that PFN0 is the start of the physical memory (RAM). This assumptions is not true on most of the ARM SOCs and hence and if one try to update the ARM port to follow the assumptions, we end of breaking the dma bounce limit for few block layer drivers. One such example is trying to unify the meaning of max*_pfn on ARM as the bootmem layer expects, breaks few block layer driver dma bounce limit. To fix this problem, we introduce dma_max_pfn(dev) generic helper with a possibility of override from the architecture code. The helper converts a DMA bitmask of bits to a block PFN number. In all the generic cases, it is just "dev->dma_mask >> PAGE_SHIFT" and hence default behavior is maintained as is. Subsequent patches will make use of the helper. No functional change. Signed-off-by: Santosh Shilimkar Signed-off-by: Russell King --- include/linux/dma-mapping.h | 7 +++++++ 1 files changed, 7 insertions(+), 0 deletions(-) diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h index 27d1421..fd4aee2 100644 --- a/include/linux/dma-mapping.h +++ b/include/linux/dma-mapping.h @@ -153,6 +153,13 @@ static inline int dma_set_seg_boundary(struct device *dev, unsigned long mask) return -EIO; } +#ifndef dma_max_pfn +static inline unsigned long dma_max_pfn(struct device *dev) +{ + return *dev->dma_mask >> PAGE_SHIFT; +} +#endif + static inline void *dma_zalloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle, gfp_t flag) {