sparsemem usage

From: moreau francis
Date: Wed Aug 02 2006 - 10:04:03 EST


My board has a really weird mem mapping.

MEM1: 0xc000 0000 - 32 Mo
MEM2: 0xd000 0000 - 8 Mo
MEM3: 0xd800 0000 - 128 Ko

MEM3 has interesting properties, such as speed and security,
and I really need to use it.

I think that sparsemem can deal with such mapping. But I
encounter an issue when choosing the section bit size. I choose
SECTION_SIZE_BITS = 17. Therefore the section size is
equal to the smallest size of my memories. But I get a
compilation error which is due to this:

#if (MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS
#error Allocator MAX_ORDER exceeds SECTION_SIZE
#endif

I'm not sure to understand why there's such check. To fix this
I should change MAX_ORDER to 6.

Is it the only way to fix that ?

Thanks

Francis


-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/