Re: [2/3] Set compatibility flag for 4GB zone on IA64

Jeff Garzik
2005-09-12T01:17:19Z

Luck, Tony wrote:
>>Luck, Tony wrote:
>>
>>>ia64 isn't all that homogeneous. SGI systems stuff *all* memory
>>>into the DMA zone as their I/O devices have no 32-bit limits (just
>>>as well really as there is no memory below 4G on an Altix!).
>>
>>SGI machines support random PCI cards, right? If so, you
>>cannot presume
>>I/O devices have no 32-bit limits.
>
>
> No, SGI machines don't support random PCI cards. The lowest
> possible physical address in an Altix is 192GB. Cards that
> can only DMA to addresses below 4G aren't going to be very
> useful, are they?

Do the boxes have IOMMUs?

Jeff