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.