Re: ZONE_DMA on MIPS

On Tue, Mar 20, 2007 at 12:09:47AM +0900, Atsushi Nemoto wrote:

Some ZONE_DMA patches were merged in 2.6.21.  On most MIPS, ZONE_DMA
is not needed, isn't it?

Currently JAZZ, MALTA, QEMU, IP22, SNI_RM, RBTX4938 defines
GENERIC_ISA_DMA so they may need ZONE_DMA (though I wonder QEMU or
RBTX4938 really need it...)

Are there any other platforms requires special DMA zone?

Qemu supports more or less the full PC braind^Wheritage, including the
good old too-old floppy controller.  IP22 supports Indigo 2 systems
which have EISA support, so we only want ZONE_DMA if EISA is enabled.
For a bunch of other systems ZONE_DMA may be required to support b0rked
PCI cards that only support like 31-bit DMA addresses or even less.

  Ralf