Re: dual head r128

On Thu, 12 Oct 2000, Kostas Gewrgiou wrote:

On Thu, 12 Oct 2000, Michel [iso-8859-1] Dänzer wrote:

quoted

So this code from the current X CVS:

    R128ReadBIOS(0x0000, info->VBIOS, R128_VBIOS_SIZE);
    if (info->VBIOS[0] != 0x55 || info->VBIOS[1] != 0xaa) {
        xf86DrvMsg(pScrn->scrnIndex, X_WARNING,
                   "Video BIOS not detected in PCI space!\n");

only checks if there is a ROM, not if it's a BIOS?

Right, from the pci spec the table is something like this
Offset    Length    Value    Description
0h          1        55h    ROM Signature, byte 1
1h          1        AAh    ROM Signature, byte 2
...
18h-19h     2        xx     Pointer to PCI Data Structure

PCI Data Structure
Offset    Length  Description
...
14           1    Code Type
..

Code Type is 0 for bios and 1 for OF

So you'll have to add one more test to check for BIOS/OF

IIRC, it's also possible to have one ROM that contains both x86 BIOS and
F-Code Open Firmware stuff. It may require compression to achieve this due to
the limited size to the ROM. I think I saw this on the Firmworks website, an
eon ago.

Gr{oetje,eeting}s,

						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds


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