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

Luck, Tony
2005-09-11T20:44:14Z

>Set compatibility flag for 4GB zone on IA64
>
>IA64 traditionally had a 4GB DMA32 zone. Set the compatibility flag
>to keep old drivers working.
>
>For new drivers it would be better to use ZONE_DMA32 now.
>
>Signed-off-by: Andi Kleen <ak@suse.de>
>Cc: tony.luck@intel.com
>
>Index: linux/arch/ia64/Kconfig
>===================================================================
>--- linux.orig/arch/ia64/Kconfig
>+++ linux/arch/ia64/Kconfig
>@@ -54,6 +54,10 @@ config IA64_UNCACHED_ALLOCATOR
> bool
> select GENERIC_ALLOCATOR
>
>+config ZONE_DMA_IS_DMA32
>+ bool
>+ default y
>+
> choice
> prompt "System type"
> default IA64_GENERIC
>

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!).

What does this ZONE_DMA_IS_DMA32 thing do?

-Tony