Re: Bug: Discontigmem virt_to_page() [Alpha,ARM,Mips64?]

Kurt Ferreira
2002-05-02T21:53:14Z

> On Thu, May 02, 2002 at 03:20:39PM -0700, Martin J. Bligh wrote:
> > IIRC, there are some funny games you can play with 32bit PCI DMA.
> > You're not necessarily restricted to the bottom 4Gb of phys addr space,
> > you're restricted to a 4Gb window, which you can shift by programming
> > a register on the card. Fixing that register to point to a window for the
> > node in question allows you to allocate from a node's pg_data_t and
> > assure DMAable RAM is returned.
> > M.
>
>
> Woops, I forgot about the BAR, thanks. Heck, IIRC you were even the one
> who told me about this trick.
>
By this do you mean setting bits BAR[2:1]=b'10? Just making sure I get
it.

Thanks
Kurt