From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755488AbcIFLeC (ORCPT ); Tue, 6 Sep 2016 07:34:02 -0400 Received: from hqemgate14.nvidia.com ([216.228.121.143]:17083 "EHLO hqemgate14.nvidia.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752958AbcIFLd6 (ORCPT ); Tue, 6 Sep 2016 07:33:58 -0400 X-PGP-Universal: processed; by hqpgpgate101.nvidia.com on Tue, 06 Sep 2016 04:33:55 -0700 Subject: Re: [PATCH v2 0/2] Add memcpy support for tegra210-adma To: Nicolin Chen , References: CC: , , , , , , From: Jon Hunter Message-ID: <319ca097-4b10-83b9-841c-52adccbb48ad@nvidia.com> Date: Tue, 6 Sep 2016 12:33:45 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.2.0 MIME-Version: 1.0 In-Reply-To: X-Originating-IP: [10.21.132.106] X-ClientProxiedBy: DRUKMAIL102.nvidia.com (10.25.59.20) To UKMAIL101.nvidia.com (10.26.138.13) Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/09/16 01:32, Nicolin Chen wrote: > This series of patches add memcpy support for tegra210 ADMA engine. Thanks. Any reason you choose this DMA and not the APB DMA? The APB DMA is more of a generic DMA and so for memcpy it would seem to be a good choice and it is available on all Tegras not just Tegra210. Furthermore, from a power standpoint the ADMA is in the audio power domain and so using it for memcpy would mean the audio power domain is turned on. It may not be a big deal for some, but given the APB is in the CORE domain (always on when not in low-power) it seems like a better choice for power as well. Cheers Jon -- nvpublic