diff options
author | Yinghai Lu <Yinghai.Lu@Sun.COM> | 2008-01-30 13:33:32 +0100 |
---|---|---|
committer | Ingo Molnar <mingo@elte.hu> | 2008-01-30 13:33:32 +0100 |
commit | 093af8d7f0ba3c6be1485973508584ef081e9f93 (patch) | |
tree | 0a2db2401e09764e654efafbea60f6d5d6894dcd /Documentation | |
parent | 11201e603d28a1cb7a4bb1d65f39e61629c97a28 (diff) |
x86_32: trim memory by updating e820
when MTRRs are not covering the whole e820 table, we need to trim the
RAM and need to update e820.
reuse some code on 64-bit as well.
here need to add early_get_cap and use it in early_cpu_detect, and move
mtrr_bp_init early.
The code successfully trimmed the memory map on Justin's system:
from:
[ 0.000000] BIOS-e820: 0000000100000000 - 000000022c000000 (usable)
to:
[ 0.000000] modified: 0000000100000000 - 0000000228000000 (usable)
[ 0.000000] modified: 0000000228000000 - 000000022c000000 (reserved)
According to Justin it makes quite a difference:
| When I boot the box without any trimming it acts like a 286 or 386,
| takes about 10 minutes to boot (using raptor disks).
Signed-off-by: Yinghai Lu <yinghai.lu@sun.com>
Tested-by: Justin Piszcz <jpiszcz@lucidpixels.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/kernel-parameters.txt | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 50d564dabb1..fe3031d5643 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -583,7 +583,7 @@ and is between 256 and 4096 characters. It is defined in the file See drivers/char/README.epca and Documentation/digiepca.txt. - disable_mtrr_trim [X86-64, Intel only] + disable_mtrr_trim [X86, Intel and AMD only] By default the kernel will trim any uncacheable memory out of your available memory pool based on MTRR settings. This parameter disables that behavior, |