Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S936627AbZLQSpY (ORCPT ); Thu, 17 Dec 2009 13:45:24 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S936558AbZLQSpW (ORCPT ); Thu, 17 Dec 2009 13:45:22 -0500 Received: from gate.crashing.org ([63.228.1.57]:36028 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S936484AbZLQSpV convert rfc822-to-8bit (ORCPT ); Thu, 17 Dec 2009 13:45:21 -0500 Subject: Re: [PATCH v2 2/2] Crypto: Talitos: Support for Async_tx XOR offload Mime-Version: 1.0 (Apple Message framework v1077) Content-Type: text/plain; charset=us-ascii From: Kumar Gala In-Reply-To: <4B2A6DFA.6000504@intel.com> Date: Thu, 17 Dec 2009 12:45:01 -0600 Cc: "Ira W. Snyder" , "herbert@gondor.apana.org.au" , "B04825@freescale.com" , "linux-kernel@vger.kernel.org" , "linux-raid@vger.kernel.org" , "linuxppc-dev@ozlabs.org" , Vishnu Suresh , "linux-crypto@vger.kernel.org" , Dipen Dudhat , Maneesh Gupta , "R58472@freescale.com" Content-Transfer-Encoding: 8BIT Message-Id: References: <1260977698-4076-1-git-send-email-Vishnu@freescale.com> <20091216164144.daff5468.kim.phillips@freescale.com> <2868C8CF-584B-4FA7-9C3B-2FACEF77527E@kernel.crashing.org> <4B296394.9010709@intel.com> <20091217170958.GE18271@ovro.caltech.edu> <4B2A6DFA.6000504@intel.com> To: Dan Williams X-Mailer: Apple Mail (2.1077) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1013 Lines: 16 On Dec 17, 2009, at 11:44 AM, Dan Williams wrote: > Ira W. Snyder wrote: >> Yes, I have used the device_prep_dma_interrupt() functionality quite a >> while back. However, I found it to be pretty much useless. > > The specific case it is needed for Talitos/raid is a channel switch interrupt. The interrupt causes the cleanup operation to be run which will kick off any pending dependent operations on the xor channel. In the raid case we only have callbacks at the end of a chain, so we need the interrupt to kick the engine in an operation chain like xor->copy->xor->callback. Ok, I'm still confused as to how the DMA interrupt interacts with the Talitos/raid side of things. The should be completely independent (separate interrupts, separate IP blocks). - k-- 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/