From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756668AbYBRSkk (ORCPT ); Mon, 18 Feb 2008 13:40:40 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753096AbYBRSkc (ORCPT ); Mon, 18 Feb 2008 13:40:32 -0500 Received: from einhorn.in-berlin.de ([192.109.42.8]:33638 "EHLO einhorn.in-berlin.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752185AbYBRSkc (ORCPT ); Mon, 18 Feb 2008 13:40:32 -0500 X-Envelope-From: stefanr@s5r6.in-berlin.de Date: Mon, 18 Feb 2008 19:40:09 +0100 (CET) From: Stefan Richter Subject: [PATCH] Documentation: correction to debugging-via-ohci1394 To: linux-kernel@vger.kernel.org cc: linux1394-devel@lists.sourceforge.net, Bernhard Kaindl , Ingo Molnar Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; CHARSET=us-ascii Content-Disposition: INLINE Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Rectify a factoid about firewire-ohci. Signed-off-by: Stefan Richter --- Ingo, I can get this to Linus via linux1394-2.6.git. Documentation/debugging-via-ohci1394.txt | 13 +++++++------ 1 file changed, 7 insertions(+), 6 deletions(-) Index: linux-2.6.25-rc2/Documentation/debugging-via-ohci1394.txt =================================================================== --- linux-2.6.25-rc2.orig/Documentation/debugging-via-ohci1394.txt +++ linux-2.6.25-rc2/Documentation/debugging-via-ohci1394.txt @@ -36,13 +36,14 @@ available (notebooks) or too slow for ex Drivers ------- -The OHCI-1394 drivers in drivers/firewire and drivers/ieee1394 initialize -the OHCI-1394 controllers to a working state and can be used to enable -physical DMA. By default you only have to load the driver, and physical -DMA access will be granted to all remote nodes, but it can be turned off -when using the ohci1394 driver. +The ohci1394 driver in drivers/ieee1394 initializes the OHCI-1394 controllers +to a working state and enables physical DMA by default for all remote nodes. +This can be turned off by ohci1394's module parameter phys_dma=0. -Because these drivers depend on the PCI enumeration to be completed, an +The alternative firewire-ohci driver in drivers/firewire uses filtered physical +DMA, hence is not yet suitable for remote debugging. + +Because ohci1394 depends on the PCI enumeration to be completed, an initialization routine which can runs pretty early (long before console_init(), which makes the printk buffer appear on the console can be called) was written. -- Stefan Richter -=====-==--- --=- =--=- http://arcgraph.de/sr/