Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758194Ab1CCKUF (ORCPT ); Thu, 3 Mar 2011 05:20:05 -0500 Received: from eu1sys200aog115.obsmtp.com ([207.126.144.139]:47000 "EHLO eu1sys200aog115.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757886Ab1CCKSd (ORCPT ); Thu, 3 Mar 2011 05:18:33 -0500 From: Viresh Kumar To: , Cc: , , , Viresh Kumar , , , , , Subject: [PATCH V2 06/13] dw_dmac: Change value of DWC_MAX_COUNT to 4095. Date: Thu, 3 Mar 2011 15:47:19 +0530 Message-ID: <0e767d5a3f538e476b72c7d5ccac88e2f5fcdf1a.1299146382.git.viresh.kumar@st.com> X-Mailer: git-send-email 1.7.2.2 In-Reply-To: References: MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1211 Lines: 37 Every descriptor can transfer a maximum count of 4095 (12 bits, in control reg), So we must have DWC_MAX_COUNT as 4095 instead of 2048 for better performance. Signed-off-by: Viresh Kumar --- drivers/dma/dw_dmac.c | 5 ++--- 1 files changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/dma/dw_dmac.c b/drivers/dma/dw_dmac.c index e5d97bf..734829f 100644 --- a/drivers/dma/dw_dmac.c +++ b/drivers/dma/dw_dmac.c @@ -47,14 +47,13 @@ /* * This is configuration-dependent and usually a funny size like 4095. - * Let's round it down to the nearest power of two. * * Note that this is a transfer count, i.e. if we transfer 32-bit - * words, we can do 8192 bytes per descriptor. + * words, we can do 16480 bytes per descriptor. * * This parameter is also system-specific. */ -#define DWC_MAX_COUNT 2048U +#define DWC_MAX_COUNT 4095U /* * Number of descriptors to allocate for each channel. This should be -- 1.7.2.2 -- 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/