Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965109AbWJXI3f (ORCPT ); Tue, 24 Oct 2006 04:29:35 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S965113AbWJXI3f (ORCPT ); Tue, 24 Oct 2006 04:29:35 -0400 Received: from gate.crashing.org ([63.228.1.57]:39626 "EHLO gate.crashing.org") by vger.kernel.org with ESMTP id S965109AbWJXI3e (ORCPT ); Tue, 24 Oct 2006 04:29:34 -0400 Subject: Re: pci_set_power_state() failure and breaking suspend From: Benjamin Herrenschmidt To: Stefan Richter Cc: linux1394-devel@lists.sourceforge.net, linuxppc-dev list , Linux Kernel list , Greg KH In-Reply-To: <453DCB17.6050304@s5r6.in-berlin.de> References: <1161672898.10524.596.camel@localhost.localdomain> <1161675611.10524.598.camel@localhost.localdomain> <453DCB17.6050304@s5r6.in-berlin.de> Content-Type: text/plain Date: Tue, 24 Oct 2006 18:29:17 +1000 Message-Id: <1161678557.10524.602.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.8.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1897 Lines: 43 > Just out of curiosity: Are these HCs actual PCI hardware or are they > glued onto an extra PCI interface? Does the startup message of ohci1394 > log OHCI 1.1 or 1.0 compliance for them? Probably the latter; OHCI 1.1 > was released in January 2000. I don't have one at hand right now but I suspect it's 1.1. I'll ask paulus tomorrow. They are cells inside an Apple ASIC but on a PCI bus (on-chip PCI bus). > OHCI 1.1 says "PCI based 1394 Open Host Controllers /should/ implement > PCI Power Management, and implementations that support PCI Power > Management /shall/ exhibit behavior consistent with this Annex." > (Emphasis mine.) I.e. a compliant HC does either not support power > management at all or supports it including the pci_set_power_state() > triggered state transitions. Well, the old Apple ones support power management but not the PCI PM states. However, there are separate magic bits in the Apple ASIC that can be used to toggle the clocks on/off (which is that the ppc specific bits do basically, along as turning off power on the bus). > OHCI 1.00 does not have a power management specification. It points to > the PCI Local Bus Specification Revision 2.1 though (which I don't have). > > We are still working on full power management support by ohci1394 and > upper IEEE 1394 layers, so I am glad to get feedback and patches. Well, the question is wether we want to make the whole machine suspend fail because there is a 1394 chip that doesn't do PCI PM in or not... I can send patches "fixing" it both ways (just ignoring the result from pci_set_power_state in general, or just ignoring that result on Apple cells). Ben. - 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/