From mboxrd@z Thu Jan 1 00:00:00 1970 From: ole.rohne-vJEk5272eHo@public.gmane.org Subject: Re: Suspend-to-RAM on Sony Vaios Date: Wed, 03 Nov 2004 15:49:28 +0100 Message-ID: References: <20041021001331.69c6c965@localhost.localdomain> <20041020225334.GC29863@elf.ucw.cz> <20041101145410.GB12006@tate.loria.fr> <20041101154127.GB1056@elf.ucw.cz> <20041102220034.GA31435@tate.loria.fr> <20041102220958.GF1407@elf.ucw.cz> <20041103105106.GA4174@wotan.suse.de> <20041103124138.GC18867@wotan.suse.de> <20041103141134.GA24195@wotan.suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: In-Reply-To: <20041103141134.GA24195-B4tOwbsTzaBolqkO4TVVkw@public.gmane.org> (Andi Kleen's message of "Wed, 3 Nov 2004 15:11:34 +0100") Sender: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Errors-To: acpi-devel-admin-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , List-Archive: To: Andi Kleen Cc: Pavel Machek , Emmanuel Thom?? , Jon Valvatne , acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org List-Id: linux-acpi@vger.kernel.org Andi> The big difference is that the kernel does all kind of complicated Andi> things to shut itself up first. What you're trying is to do the Andi> same thing halfway through the initialization sequence when Andi> a lot of hardware is already running again. Especially on x86-64 Andi> going back out of long mode is a really intrusive operation, Andi> killing all interrupt state etc. There shouldn't be any state to kill at this point. IMO, hardware resume should happen *before* interrupts, bus mastering and SMP, and I think the ACPI spec support that view. The "lot of hardware is already running again" should only include stuff that appears before the graphics in bus-enumeration order. It's a pity though the two-phase resume model was abandoned. >> I'm sure that could be tried... I'd guess this is the way Windows does >> it, initializing everything and the kitchen sink before even returning >> to PM. Andi> You just need to initialize the same things the boot BIOS does Andi> before calling the video POST after power up. That would be Andi> probably AGP and PCI. Sorry, my reference to Windows wasn't meant to imply this way is difficult or wrong. Rather, I'm just frustrated by the lack of spec and we don't plainly *know* what the "reference" implementation does. Andi> I hope the PCI BIOS has a function for this though. I don't have Andi> a spec for it unfortunately. You might be lucky here, I think PCI BIOS is documented. >> There is just too much stuff even in kernel space that depends on the Andi> The only code in the kernel that should care about video mode Andi> state is the fbcon console driver. Possibly DRI too, but those Andi> are firmly under user control and can be handled by the X server. What about the random console printing that goes on during suspend/resume? Ole ------------------------------------------------------- This SF.Net email is sponsored by: Sybase ASE Linux Express Edition - download now for FREE LinuxWorld Reader's Choice Award Winner for best database on Linux. http://ads.osdn.com/?ad_id=5588&alloc_id=12065&op=click