From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jon Smirl Subject: Re: [RFC] Reliable video POSTing on resume Date: Fri, 4 Feb 2005 21:30:36 -0500 Message-ID: <9e47339105020418306a4c2c93@mail.gmail.com> References: <20050122134205.GA9354@wsc-gmbh.de> <1107474198.5727.9.camel@desktop.cunninghams> <4202DF7B.2000506@gmx.net> <9e47339105020321031ccaabb@mail.gmail.com> <420367CF.7060206@gmx.net> <20050204163019.GC1290@elf.ucw.cz> <9e4733910502040931955f5a6@mail.gmail.com> <1107569089.8575.35.camel@tyrosine> <9e4733910502041809738017a7@mail.gmail.com> <1107569842.8575.44.camel@tyrosine> Reply-To: Jon Smirl Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit In-Reply-To: <1107569842.8575.44.camel@tyrosine> 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: Matthew Garrett Cc: Pavel Machek , Carl-Daniel Hailfinger , ncunningham-jjFNsPSvq+iXDw4h08c5KA@public.gmane.org, ACPI List , Linux Kernel Mailing List List-Id: linux-acpi@vger.kernel.org On Sat, 05 Feb 2005 02:17:22 +0000, Matthew Garrett wrote: > On laptops, it's frequently the case that c000:0003 will jump to a > section of code that is no longer mapped into the address space. > Instead, it's entirely possible that some other section of BIOS will be > mapped there. The resulting behaviour is undefined, and can cause the > hardware to hang. I suspect the problem in that case is a compressed VBIOS. Some laptops compress the VBIOS and the system BIOS into a single ROM and then expand them at power on. Sounds like this is not happening on resume. To get around the problem copy the image from C000:0 before suspend to a place in preserved RAM where wakeup.S can find it and then copy it back to C000:0 on resume. To test for this checksum C000:0 before suspend and after and see if it has changed. You can always do a simple test. If a program like vbios.vm86 or vbetool can reset the card, then there is no reason wakeup.S shouldn't be able to do it too if the environment is set up correctly. -- Jon Smirl jonsmirl-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org ------------------------------------------------------- This SF.Net email is sponsored by: IntelliVIEW -- Interactive Reporting Tool for open source databases. Create drag-&-drop reports. Save time by over 75%! Publish reports on the web. Export to DOC, XLS, RTF, etc. Download a FREE copy at http://www.intelliview.com/go/osdn_nl