Re: ZONE_DMA on MIPS

On Mon, 19 Mar 2007 15:48:21 +0000, Ralf Baechle [off-list ref] wrote:

quoted

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.

Hmm... So do you think making ZONE_DMA customizable for each platform
(or user configurable) would have some sense?

For these legacy(?) PCI cards, we can check if it works or not by
pci_set_dma_mask(), at least.

---
Atsushi Nemoto