Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755473Ab2IAD6m (ORCPT ); Fri, 31 Aug 2012 23:58:42 -0400 Received: from bosmailout11.eigbox.net ([66.96.186.11]:47360 "EHLO bosmailout11.eigbox.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755265Ab2IAD6k (ORCPT ); Fri, 31 Aug 2012 23:58:40 -0400 X-Authority-Analysis: v=2.0 cv=aPZHX8Bm c=1 sm=1 a=Z/nPm8Wi6vkzxh11zJE/RA==:17 a=bc2JKO6qiGsA:10 a=tW0haWE2Y5YA:10 a=cCnm7YsJ2HMA:10 a=8nJEP1OIZ-IA:10 a=jKtTQB-Zx8sA:10 a=bJ0fqD8TFZgqkSadqForXVIPBlU=:19 a=D19gQVrFAAAA:8 a=KKAkSRfTAAAA:8 a=fUsd2VqqzTs3fo_v_LkA:9 a=wPNLvfGTeEIA:10 a=WwgC8nHKvroA:10 a=yRkwU2vzfO47fUBn:21 a=lW_zb_dH2mA-rEXF:21 a=eBvjjtMVdWwtQGedh7GyLg==:117 X-EN-OrigOutIP: 10.20.18.5 X-EN-IMPSID: tfHv1j00406Zqne01fHvXl Message-ID: <50417B7E.50508@yahoo.es> Date: Sat, 01 Sep 2012 11:05:34 +0800 From: Hein Tibosch User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:15.0) Gecko/20120824 Thunderbird/15.0 MIME-Version: 1.0 To: Andrew Morton , viresh kumar , Hans-Christian Egtvedt , Arnd Bergmann CC: spear-devel , Linux Kernel Mailing List , "ludovic.desroches" , Havard Skinnemoen , Nicolas Ferre Subject: [PATCH v3 2/3] dw_dmac: max_mem_width limits value for SRC/DST_TR_WID register Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-EN-UserInfo: 3946c951b80c12a8be5482963a0b1232:e0ae43bc192b431f8b69f09a37527cbc X-EN-AuthUser: hein@htibosch.net X-EN-OrigIP: 114.79.63.40 X-EN-OrigHost: unknown Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2779 Lines: 82 The dw_dmac driver was earlier adapted to do 64-bit transfers on the memory side (see https://lkml.org/lkml/2012/1/18/52) This works on ARM platforms but for AVR32 (AP700x) the maximum allowed transfer size is 32-bits. This patch allows the arch code to set a new slave property max_mem_width to limit the size. Allowable values are: #define DW_MEM_WIDTH_64 0 /* default */ #define DW_MEM_WIDTH_32 1 /* e.g. for avr32 */ Signed-off-by: Hein Tibosch Acked-by: Viresh Kumar --- drivers/dma/dw_dmac.c | 10 +++++++--- include/linux/dw_dmac.h | 3 +++ 2 files changed, 10 insertions(+), 3 deletions(-) diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c index 7212961..11f8542 100644 --- a/drivers/dma/dw_dmac.c +++ b/drivers/dma/dw_dmac.c @@ -618,6 +618,7 @@ dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, size_t len, unsigned long flags) { struct dw_dma_chan *dwc = to_dw_dma_chan(chan); + struct dw_dma_slave *dws = chan->private; struct dw_desc *desc; struct dw_desc *first; struct dw_desc *prev; @@ -639,7 +640,8 @@ dwc_prep_dma_memcpy(struct dma_chan *chan, dma_addr_t dest, dma_addr_t src, * We can be a lot more clever here, but this should take care * of the most common optimization. */ - if (!((src | dest | len) & 7)) + if (dws->max_mem_width == DW_MEM_WIDTH_64 && + !((src | dest | len) & 7)) src_width = dst_width = 3; else if (!((src | dest | len) & 3)) src_width = dst_width = 2; @@ -746,7 +748,8 @@ dwc_prep_slave_sg(struct dma_chan *chan, struct scatterlist *sgl, mem = sg_dma_address(sg); len = sg_dma_len(sg); - if (!((mem | len) & 7)) + if (dws->max_mem_width == DW_MEM_WIDTH_64 && + !((mem | len) & 7)) mem_width = 3; else if (!((mem | len) & 3)) mem_width = 2; @@ -813,7 +816,8 @@ slave_sg_todev_fill_desc: mem = sg_dma_address(sg); len = sg_dma_len(sg); - if (!((mem | len) & 7)) + if (dws->max_mem_width == DW_MEM_WIDTH_64 && + !((mem | len) & 7)) mem_width = 3; else if (!((mem | len) & 3)) mem_width = 2; diff --git a/include/linux/dw_dmac.h b/include/linux/dw_dmac.h index 2412e02..330afb2 100644 --- a/include/linux/dw_dmac.h +++ b/include/linux/dw_dmac.h @@ -58,6 +58,9 @@ struct dw_dma_slave { u32 cfg_lo; u8 src_master; u8 dst_master; +#define DW_MEM_WIDTH_64 0 +#define DW_MEM_WIDTH_32 1 /* e.g. for avr32 */ + u8 max_mem_width; }; /* Platform-configurable bits in CFG_HI */ -- 1.7.8.0 -- 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/