From 093af8d7f0ba3c6be1485973508584ef081e9f93 Mon Sep 17 00:00:00 2001 From: Yinghai Lu Date: Wed, 30 Jan 2008 13:33:32 +0100 Subject: 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 Tested-by: Justin Piszcz Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner --- Documentation/kernel-parameters.txt | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'Documentation') diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 50d564d..fe3031d 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, -- cgit v1.1