From mboxrd@z Thu Jan 1 00:00:00 1970 From: Russell King - ARM Linux Subject: Re: [PATCH net-next 5/7] net:fec: add support for dumping transmit ring on timeout Date: Fri, 30 May 2014 01:03:36 +0100 Message-ID: <20140530000336.GM3693@n2100.arm.linux.org.uk> References: <1398773350-7293-1-git-send-email-Frank.Li@freescale.com> <1398773350-7293-5-git-send-email-Frank.Li@freescale.com> <063D6719AE5E284EB5DD2968C1650D6D0F7014F0@AcuExch.aculab.com> <063D6719AE5E284EB5DD2968C1650D6D0F701524@AcuExch.aculab.com> <063D6719AE5E284EB5DD2968C1650D6D0F70156E@AcuExch.aculab.com> <20140429143828.GB26756@n2100.arm.linux.org.uk> <51ca1e44e5e849ecbae40bf0beaa2028@BY2PR03MB377.namprd03.prod.outlook.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: David Laight , 'Frank Li' , "Frank.Li@freescale.com" , "shawn.guo@linaro.org" , "davem@davemloft.net" , "netdev@vger.kernel.org" To: "fugang.duan@freescale.com" Return-path: Received: from gw-1.arm.linux.org.uk ([78.32.30.217]:38757 "EHLO pandora.arm.linux.org.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751538AbaE3AFP (ORCPT ); Thu, 29 May 2014 20:05:15 -0400 Content-Disposition: inline In-Reply-To: <51ca1e44e5e849ecbae40bf0beaa2028@BY2PR03MB377.namprd03.prod.outlook.com> Sender: netdev-owner@vger.kernel.org List-ID: On Thu, May 29, 2014 at 08:17:07AM +0000, fugang.duan@freescale.com wrote: > Hi, Russell, > > I see linux next and net "imx_v6_v7_defconfig" don't enable "CONFIG_CMA", > if you enable the feature, Sorry, telling people that CMA is required to avoid that is just not an acceptable "solution". With CMA not enabled, the DMA memory provided to the driver is still perfectly valid and should be no different from what CMA provides. I'd strongly suggest investigating why there is this difference, and what the difference is - I'd assume freescale have the ability to do that with their own devices much more than I have, and probably to a greater depth too - especially as there is no possibility what so ever of using any kind of hardware debug on the iMX6 platforms I have. -- FTTC broadband for 0.8mile line: now at 9.7Mbps down 460kbps up... slowly improving, and getting towards what was expected from it.