From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jon Smirl Subject: Re: [RFC] Reliable video POSTing on resume Date: Sat, 5 Feb 2005 10:55:29 -0500 Message-ID: <9e47339105020507552d93bd79@mail.gmail.com> References: <20050122134205.GA9354@wsc-gmbh.de> <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> <9e47339105020418306a4c2c93@mail.gmail.com> <1107591336.8575.51.camel@tyrosine> Reply-To: Jon Smirl Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit In-Reply-To: <1107591336.8575.51.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 08:15:35 +0000, Matthew Garrett wrote: > On Fri, 2005-02-04 at 21:30 -0500, Jon Smirl wrote: > > > 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. > > No, that's not what's happening. If you disassemble the code at > c000:blah in a laptop, you'll often find that it jumps off to a > completely different section of address space. During POST, that > contains video BIOS. After POST, it may be something like USB boot > support. Without reading it directly out of flash, it's not possible to > recover that code. If the copy left at C000:0 is jumping off to F000:xx (system BIOS) that is a valid thing to do and the reset program may need more emulation hooks. If it is jumping off somewhere else then I would consider that a broken VBIOS since jumping to C000:3 for reset is part of how VGA is supposed to work. If this is happening on an ATI or Nvidia chip you're probably never going to get video resume working. -- 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