summaryrefslogtreecommitdiff
path: root/src/cpu/x86
diff options
context:
space:
mode:
authorPatrick Rudolph <patrick.rudolph@9elements.com>2020-08-15 06:14:57 +0200
committerPatrick Rudolph <siro@das-labor.org>2020-08-19 09:07:58 +0000
commite3dd57e1061760d37a3b1e38fc9a9c1ff9fdba66 (patch)
tree5afb698c09cb054ef67afa612d06c20779b71645 /src/cpu/x86
parente563815e059ef5881a42e6f8b37094783771d5a7 (diff)
cpu/x86/64bit/exit32: Add support for ramstage
When compiled in RAMSTAGE use the segments for ramstage. Allows to call this assembly code in ramstage to exit long mode. The next commit makes use of this. Tested on qemu: Still boots on x86_64. Change-Id: I8beb31866bd15afc206b480b1ba05df995adc402 Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com> Reviewed-on: https://review.coreboot.org/c/coreboot/+/44504 Tested-by: build bot (Jenkins) <no-reply@coreboot.org> Reviewed-by: Arthur Heymans <arthur@aheymans.xyz> Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Diffstat (limited to 'src/cpu/x86')
-rw-r--r--src/cpu/x86/64bit/exit32.inc12
1 files changed, 10 insertions, 2 deletions
diff --git a/src/cpu/x86/64bit/exit32.inc b/src/cpu/x86/64bit/exit32.inc
index 48837d96a9..6722cfdf3f 100644
--- a/src/cpu/x86/64bit/exit32.inc
+++ b/src/cpu/x86/64bit/exit32.inc
@@ -12,14 +12,22 @@
#include <cpu/x86/msr.h>
#include <cpu/x86/cr.h>
+#if defined(__RAMSTAGE__)
+#include <arch/ram_segs.h>
+#define CODE_SEG RAM_CODE_SEG
+#define DATA_SEG RAM_DATA_SEG
+#else
#include <arch/rom_segs.h>
+#define CODE_SEG ROM_CODE_SEG
+#define DATA_SEG ROM_DATA_SEG
+#endif
drop_longmode:
/* Ensure cache is clean. */
wbinvd
/* Set 32-bit code segment and ss */
- mov $ROM_CODE_SEG, %rcx
+ mov $CODE_SEG, %rcx
/* SetCodeSelector32 will drop us to protected mode on return */
call SetCodeSelector32
@@ -54,7 +62,7 @@ __longmode_compatibility:
/* Running in 32-bit compatibility mode */
/* Use flat data segment */
- movl $ROM_DATA_SEG, %eax
+ movl $DATA_SEG, %eax
movl %eax, %ds
movl %eax, %es
movl %eax, %ss