From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Evert van Grootheest Subject: DMA on ht6560b? Date: Mon, 18 Feb 2008 15:13:53 +0100 Message-ID: <47B992A1.2030008@caiway.nl> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from pelian.kabelfoon.nl ([62.45.45.43]:52926 "EHLO pelian.kabelfoon.nl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751441AbYBRONy (ORCPT ); Mon, 18 Feb 2008 09:13:54 -0500 Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: linux-ide@vger.kernel.org, bzolnier@gmail.com Hi, With digging into the code... I think the ht6560b controller supports DMA. At least it did so in 2.2 (where hdparm could still turn it on). DMA in 2.2 would improve the HD from about 1M/s to 4M/s. So that's quite interesting. Also the datasheet claims that there is full ANSI ATA-4a support. According to the ATA table on wikipedia that should include up to mwdma 2 and udma33. What's the magic that will turn it on for the ht6560b controller? I would guess at the [sm]wdma_mask fields in hwif_t? Plus something for set_dma_mode? Some help would be appreciated. Thanks, Jan Evert