[PATCH] Allow small areas in io_block_mapping

Dan Malek dan at embeddededge.com
Sat Nov 17 03:57:13 EST 2001

Adrian Cox wrote:

> I hadn't realised that ioremap could be used before vmalloc was working,
> but on examining the code, it looks like it can. So I may just change my
> code to use ioremap.

Yeah, but just remember it does 1:1 virt->phys mapping.  I have a couple
of 4xx processors with hard-wired low physical addresses, and I have to
force them to map to a "friendly" virtual address :-).  That's the
only reason I like io_block_mapping(), but I don't have BATs to deal with.

> In defense of the patch....

You are correct.  The comments in the code are kind of funny.....ensure
you call it with the right parameters, but then it checks some anyway.

> That's pretty well what I need here.

Let's do it.  I think io_block_mapping() was conceptually copied from
other architectures for consistency, but I don't think it's doing the
right thing for us in all cases.


	-- Dan

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