From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nishanth Menon Subject: Re: [PATCH v4] OMAP2+: PM: omap device: API's for handling mstandby mode Date: Fri, 19 Nov 2010 09:32:42 -0600 Message-ID: <4CE6989A.7070007@ti.com> References: <1290151312-347-1-git-send-email-manjugk@ti.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from na3sys009aog107.obsmtp.com ([74.125.149.197]:55354 "EHLO na3sys009aog107.obsmtp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754679Ab0KSPcq (ORCPT ); Fri, 19 Nov 2010 10:32:46 -0500 Received: by vws1 with SMTP id 1so2355811vws.9 for ; Fri, 19 Nov 2010 07:32:45 -0800 (PST) In-Reply-To: <1290151312-347-1-git-send-email-manjugk@ti.com> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: "G, Manjunath Kondaiah" Cc: linux-omap@vger.kernel.org, Kevin Hilman , Paul Walmsley , linux-arm-kernel@lists.infradead.org G, Manjunath Kondaiah had written, on 11/19/2010 01:21 AM, the following: > Certain errata's in OMAP2+ processors will require forcing > master standby to "no standby" mode before completing on going > operation. Without this, the results will be unpredictable. > [..] > These API's are required for multiple DMA errata's which require > putting DMA controller in no mstandby mode before stopping dma. > > The applicable errata's: > 1. Errata ID: i557(Applicable for omap36xx all ES versions) > The channel hangs when the Pause bit (DMA4_CDPi [7] ) is cleared > through config port while in Standby. > > 2. Errata ID: i541(all omap2plus except omap4) > sDMA FIFO draining does not finish > > 3. OMAP3430 ES1.0(Errata ID:i88) will require DMA to be put in > no mstandby mode before disabling the channel after completing > the data transfer operation. Minor feedback from what I got from an offline comment: 1 bug = Erratum 1+ bug = Errata -- Regards, Nishanth Menon