From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753117Ab1HOMWj (ORCPT ); Mon, 15 Aug 2011 08:22:39 -0400 Received: from mail-bw0-f46.google.com ([209.85.214.46]:48340 "EHLO mail-bw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752873Ab1HOMWh (ORCPT ); Mon, 15 Aug 2011 08:22:37 -0400 Message-ID: <4E490F8A.3090702@petalogix.com> Date: Mon, 15 Aug 2011 14:22:34 +0200 From: Michal Simek Reply-To: michal.simek@petalogix.com User-Agent: Thunderbird 2.0.0.22 (X11/20090625) MIME-Version: 1.0 To: Eli Billauer CC: LKML Subject: Re: Microblaze, DMA and cache: Lack of sync functions? References: <4E464DF0.7030401@billauer.co.il> In-Reply-To: <4E464DF0.7030401@billauer.co.il> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Eli Billauer wrote: > Hello, > > > Before I make a needless hack, please correct me if I'm wrong: in > arch/microblaze/kernel/dma.c, the sync_single_for_cpu, > sync_single_for_device and friends are not set in the dma_direct_ops > structure (and not implemented), so calls from drivers to the > corresponding functions will do nothing. Since the Microblaze cache > doesn't update automatically on DMA operations, this looks like a bug to > me: The driver thinks the cache has been flushed or updated, but it > actually hasn't. > > > Map and unmap methods are indeed implemented and registered, and they > both call an internal function to sync the cache. So why are there no > sync functions? > It is not the bug just unimplemented feature and I haven't had any problem that these functions are not implemented. Implementation should be pretty straight forward. Patches welcomed. Thanks, Michal -- Michal Simek, Ing. (M.Eng) PetaLogix - Linux Solutions for a Reconfigurable World w: www.petalogix.com p: +61-7-30090663,+42-0-721842854 f: +61-7-30090663