Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932312AbWJJKjZ (ORCPT ); Tue, 10 Oct 2006 06:39:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751558AbWJJKjY (ORCPT ); Tue, 10 Oct 2006 06:39:24 -0400 Received: from gprs189-60.eurotel.cz ([160.218.189.60]:39613 "EHLO amd.ucw.cz") by vger.kernel.org with ESMTP id S1751493AbWJJKjY (ORCPT ); Tue, 10 Oct 2006 06:39:24 -0400 Date: Tue, 10 Oct 2006 12:39:10 +0200 From: Pavel Machek To: =?iso-8859-1?Q?Fr=E9d=E9ric?= Riss Cc: Linux Kernel list , Linus Torvalds , len.brown@intel.com Subject: Re: 2.6.18 suspend regression on Intel Macs Message-ID: <20061010103910.GD31598@elf.ucw.cz> References: <1160417982.5142.45.camel@funkylaptop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1160417982.5142.45.camel@funkylaptop> X-Warning: Reading this can be dangerous to your mental health. User-Agent: Mutt/1.5.11+cvs20060126 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2621 Lines: 73 Hi! > Well, I'm not sure it qualifies as a regression, because AFAIK no > official kernels can s2ram/resume Intel Macs correctly out of the box. ... > There has already been some discussion about the SCI_EN ACPI control bit > not being set when the Mactel boxes come out of suspend to ram. > http://marc.theaimsgroup.com/?l=linux-acpi&m=114957637501557&w=2 > http://marc.theaimsgroup.com/?l=linux-kernel&m=115005083610700&w=2 > http://bugme.osdl.org/show_bug.cgi?id=6670 > > The symptom is: > irq 9: nobody cared (try booting with the "irqpoll" option) > Disabling IRQ #9 > when the system comes out of sleep, making ACPI non-functional. > > Two days after having released 2.6.17, Linus commited a fix for this > issue in his tree (commit 5603509137940f4cbc577281cee62110d4097b1b): If fix was in 2.6.18-gitX, yes, that probably counts as a regression. > I since then used lightly patched 2.6.17 kernels on my MacMini without a > problem. With the release of 2.6.18, I decided to switch to a vanilla > kernel but I realized that the above issue reappeared. > > I tracked it down to the ACPI merge that took place on July 1st. More > precisely the commit 967440e3be1af06ad4dc7bb18d2e3c16130fe067 (ACPI: > ACPICA 20060623) contains the following hunk: > > @@ -635,6 +663,25 @@ acpi_status acpi_hw_register_write(u8 us > > case ACPI_REGISTER_PM1_CONTROL: /* 16-bit access */ > > + /* > + * Perform a read first to preserve certain bits (per ACPI spec) > + * > + * Note: This includes SCI_EN, we never want to change this bit > + */ > + status = acpi_hw_register_read(ACPI_MTX_DO_NOT_LOCK, > + ACPI_REGISTER_PM1_CONTROL, > + &read_value); > + if (ACPI_FAILURE(status)) { > + goto unlock_and_exit; > + } > + > + /* Insert the bits to be preserved */ > + > + ACPI_INSERT_BITS(value, ACPI_PM1_CONTROL_PRESERVED_BITS, > + read_value); > + > + /* Now we can write the data */ > + > status = > acpi_hw_low_level_write(16, value, > &acpi_gbl_FADT->xpm1a_cnt_blk); > > > which makes Linus' fix a no-op, because it disallows setting the SCI_EN > bit. Okay, just submit a (tested) patch. (And add massive comments why it is neccessary on mac mini). Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html - 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/