-----Original Message----- From: Carl-Daniel Hailfinger [mailto:c-d.hailfinger.devel.2006@gmx.net] Sent: Saturday, October 30, 2010 07:40 PM To: Scott Duplichan Cc: coreboot@coreboot.org Subject: Re: [coreboot] how to prevent legacy resource conflictwith multiple VGA cards
]On 30.10.2010 07:07, Scott Duplichan wrote: ]> Whew, finally solved this problem. 1600 x 1200 32-bit color is now working ]> with the Win7 in-box ATI driver. The problem is that some important ]> information is passed from coreboot to the ATI video driver, and some of ]> it was incorrect. The information is passed by placing it in the last ]> 512 bytes of the frame buffer, so it is easy to look at. The format of ]> the information is in struct ATOM_INTEGRATED_SYSTEM_INFO_V2. ]> ]> I should have thought of this when the slow HT link problem resulted in ]> screen tearing. The driver tries to never let this happen. One of the ]> items passed to the driver is HT link frequency and width. Hard-coded ]> values were used for link frequency and width, and frequency was invalid. ]> Apparently the driver skipped the bandwidth checks because of this. ]> ]> I believe with this change, Win7 will be able to get through setup ]> smoothly and most everything will be working. There are several more ]> patches to submit before mahogany_fam10 will have all of the Win7 changes.
]Awesome detective work, Scott!
Well darn, still not there yet. Last night, I booted in a low resolution mode and then successfully switched into 32-bit 1600x1200. Now I find that this mode from the start is not reliable. Also, Microsoft's dxdiag (direct x test) causes a crash. The ATI Atom table is now identical to that of the reference BIOS. Debug continues...
Thanks, Scott
]If you ever have the time, please write down all the stuff you had to go ]through to find and fix the bugs you encountered, or at least talk about ]it and record it with your MP3 player so someone else can transcribe it. ]Transcribing may be a task suitable for Google Code-in 2010 because it ]adds documentation about the project. ] ]Regards, ]Carl-Daniel