controlfb.c bug in VRAM bank2 check if bank1

Michel Lanners mlan at
Sat Sep 11 04:33:11 EST 1999

On  10 Sep, this message from Lou Langholtz echoed through cyberspace:
> After getting an extra 2MB VRAM for my PowerMac7500 and seeing that only
> 2MB were still being recognized (despite having just added the 2MB to
> total to 4MB VRAM), I dug into the controlfb.c code from 2.2.11 and
> 2.2.12 and made the following changes to get all 4MB VRAM recognized:

> <  out_8(&p->frame_buffer[0x600000], 0xa5);
> <  out_8(&p->frame_buffer[0x600001], 0x38);
> ---
>>  out_8(&p->frame_buffer[0x200000], 0xa5);
>>  out_8(&p->frame_buffer[0x200001], 0x38);

Hmm, if I remember right, there have been half a dozen patch pairs that
changed 0x600000 to 0x200000 and back over the years ;-)

I guess it's time to clear thgis up once and for all. By the way, I do
have 4 MB of VRAM, and all of it is detected with the current version
of controlfb.....


Michel Lanners                 |  " Read Philosophy.  Study Art.
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L-1710 Luxembourg              |
email   mlan at            |        |                     Learn Always. "

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