From c1b7e8a60be9853b5b00fc70615cea2fa8bfafc5 Mon Sep 17 00:00:00 2001 From: Patrick Rudolph Date: Thu, 21 Feb 2019 10:27:04 +0100 Subject: cpu/x86/pae/pgtbl: Add memset with PAE To clear all DRAM on x86_32, add a new method that uses PAE to access more than 32bit of address space. Add Documentation as well. Required for clearing all system memory as part of security API. Tested on wedge100s: Takes less than 2 seconds to clear 8GiB of DRAM. Tested on P8H61M-Pro: Takes less than 1 second to clear 4GiB of DRAM. Change-Id: I00f7ecf87b5c9227a9d58a0b61eecc38007e1a57 Signed-off-by: Patrick Rudolph Reviewed-on: https://review.coreboot.org/c/coreboot/+/31549 Reviewed-by: Philipp Deppenwiese Tested-by: build bot (Jenkins) --- Documentation/security/memory_clearing.md | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'Documentation/security/memory_clearing.md') diff --git a/Documentation/security/memory_clearing.md b/Documentation/security/memory_clearing.md index 3d985925d9..e5c19256b9 100644 --- a/Documentation/security/memory_clearing.md +++ b/Documentation/security/memory_clearing.md @@ -42,3 +42,7 @@ Without MTRRs (and caches enabled) clearing memory takes multiple seconds. As some platforms place code and stack in DRAM (FSP1.0), the regions can be skipped. + +## Architecture specific implementations + +* [x86 PAE](../arch/x86/pae.md) -- cgit v1.2.3