Re: Resolution problems with i810 driver, Intel 915GM & 855resolution

Hi Mark,

> I used to play around with 855resolution, trying to get 1280x720 for
> HDTV on my i865.

I took the time to look at the 855resolution code, and you're right,
it's not that complicated.

> IIRC there was a routine that enabled write mode in the BIOS, then
> another routine to make it read-only again

Yup, found it:

static void unlock_bios(void) {
    outl(0x8000005a, 0xcf8);
    outb(0x33, 0xcfe);
}

static void relock_bios(void) {
    outl(0x8000005a, 0xcf8);
    outb(0x11, 0xcfe);
}

> let me know if you have any trouble and I can probably generate a
> diff.

That would be really cool - because I have no idea where the magic
numbers come from, and which ones would be appropriate for the 915GM.
I looked at the outl/outb documentation, but obviously the values are
hardware specific.  Can you, or anybody on the list, give me some
pointers?

Thanks!

- Michael