From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefan =?utf-8?q?D=C3=B6singer?= Subject: Re: Re: Samsung P35 and S3 suspend Date: Thu, 16 Dec 2004 22:26:43 +0100 Message-ID: <200412162226.43166.stefandoesinger@gmx.at> References: <41BFC3AD.5030001@gmx.net> <200412162157.02741.stefandoesinger@gmx.at> <1103231402.5984.84.camel@tyrosine> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1103231402.5984.84.camel@tyrosine> Content-Disposition: inline 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: acpi-devel-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org Cc: Matthew Garrett List-Id: linux-acpi@vger.kernel.org > It turns out that this works badly. A large number of machines have code > at c000:0003 that jumps to somewhere else in the video ROM - this > executes a small amount of code (normally turning off the screen) and > then jumps elsewhere. In laptop hardware, this second jump is often to > code that is no longer mapped into address space. I've seen several > machines where trying to run POST code under XFree's x86 emulator fails > because it suddenly hits a pile of binary that looks nothing like the > x86 instruction set. This is partially true for my system. The instruction at c000:0003 is a JMP. But the code seems to remain in the area around 0xc0000. A jump somewhere else is a good explanation for the crashes on some machines. Is this code used by the system bios to boot the VGA card when powering on the machine? > POSTing will help in some cases (it seems to work well on Thinkpads), > but it's not a universal cure. I've had more joy with saving and > restoring the VBE state. Is this the vbestate utility? I'll have a look at it. What does vm86_video_post do? It looks like another lrmi based "call c000:0003 utility". Can only saving and restoring the VBE state bring the card back to live or do I need to call the reset routine in any case? Stefan ------------------------------------------------------- SF email is sponsored by - The IT Product Guide Read honest & candid reviews on hundreds of IT Products from real users. Discover which products truly live up to the hype. Start reading now. http://productguide.itmanagersjournal.com/