diff options
Diffstat (limited to 'src/arch/x86/timestamp.inc')
-rw-r--r-- | src/arch/x86/timestamp.inc | 33 |
1 files changed, 33 insertions, 0 deletions
diff --git a/src/arch/x86/timestamp.inc b/src/arch/x86/timestamp.inc new file mode 100644 index 0000000000..3115c22c67 --- /dev/null +++ b/src/arch/x86/timestamp.inc @@ -0,0 +1,33 @@ +/* + * This file is part of the coreboot project. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +/* + * Store the initial timestamp for booting in mmx registers. This works + * because the bootblock isn't being compiled with MMX support so mm0 and + * mm1 will be preserved into romstage. + */ + .code32 + +.global stash_timestamp +stash_timestamp: + + /* Save the BIST value */ + movl %eax, %ebp + + finit + rdtsc + movd %eax, %mm0 + movd %edx, %mm1 + + /* Restore the BIST value to %eax */ + movl %ebp, %eax |