High Memory problem on 2.4.22 Linux, 2GB ppc card
rukseninanir at gmail.com
Wed Jul 2 23:32:03 EST 2008
I want to change the MAX_LOW_MEM to 1520 MB, what other settings do i
need to change? I do not want to use HIGHMEM because the Fiber channel
does not support highmem. The card is 2 GB ppc. 1520 MB is enough. At
the moment card works with 1456 MB MAX_LOW_MEM.
Ruksen INANIR wrote:
> Hi all,
> I am working on a PPC Motorola card, which runs Linux 2.4.22. The
> card has 2 GB onboard memory. But with use 1456 MB of the available
> memory. To increase the memory capacity i need to increase the
> used memory at least 64 MB. With CONFIG_HIGHMEM option all of the 2 GB
> memory can be used but, but the fc driver on the card has no high
> memory support, so this caused problems.
> Then i saw that the memory is limited to 1456 by
> #define MAX_LOW_MEM 0x5B000000 setting in pgtable.c. I
> tried to increase it by 64 MB but i could only increase the value of
> MAX_LOW_MEM by 47 MB (1503 MB) without CONFIG_HIGHMEM option.
> 1)Is there any other setting that i should set other than
> MAX_LOW_MEM to increase the usable memory to 1520 ?
> 2)I knew that the addressable physical memory without high memory
> option was 1 G. How was it possible to address 1503 MB without
> CONFIG_HIGHMEM ? What is the max usable memory for 2.4.22 kernel?
More information about the Linuxppc-embedded