On Tue, Jan 25, 2011 at 05:06:28PM -0800, David Rientjes wrote:
CONFIG_GENERIC_ISA_DMA and CONFIG_ISA_DMA_API usually have dependencies
on one another depending on the architecture and generic kernel code uses
either to determine whether an ISA-style DMA API is configured.
Wrong.
GENERIC_ISA_DMA enables support for the standard ISA DMA allocator found
in kernel/dma.c
ISA_DMA_API says that a platform supports the ISA DMA interfaces.
An architecture can provide the ISA DMA interfaces, but not use the
standard ISA DMA allocator found in kernel/dma.c. Such as the one in
arch/arm/kernel/dma.c.
So on ARM, we have platforms where ISA_DMA_API=y but GENERIC_ISA_DMA=n.
This patch unifies both options and consolidates them into a single
option: CONFIG_GENERIC_ISA_DMA. It is also a prerequisite for a 1% text
savings for a future x86 patch that allows these options to be disabled
on that architecture when CONFIG_ZONE_DMA also becomes configurable.
NAK. This is wrong.