Re: Help with mapping memory into kernel space?

From: Daniel Gryniewicz
Date: Wed Aug 18 2004 - 10:34:18 EST


On Tue, 2004-08-17 at 22:39 -0700, Brian McGrew wrote:
> Good day All:
>

<snip>

> The overall problem is that the more system memory we install,
> the fewer IBB's we can use. For instance, 256MB lets us use
> four IBB's; 512MB lets us use three IBB's and so on. Basicly,
> the kernel blows up trying to map memory. Each IBB has two
> banks of 64MB of RAM on them which we try and memmap to system
> memory for speed of addressing. So essentaily, we're sending
> out four camera systems with only 256MB of memory which is only
> about one quarter of what we need.

On x86, the kernel has 1 GiB of address space. Try the 2G/2G split
patches, or the 4G/4G patches, either one of which should increase your
kernel address space enough to map both memory and your buffers.

Daniel
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