summaryrefslogtreecommitdiff
path: root/src/arch/x86/lib
diff options
context:
space:
mode:
authorAaron Durbin <adurbin@chromium.org>2013-02-08 16:56:51 -0600
committerStefan Reinauer <stefan.reinauer@coreboot.org>2013-03-21 18:01:38 +0100
commita146d58ca0375a12f23dc5a4bd25adfa3423114f (patch)
tree874776d78835bf56ba66eba54e2558edd97645de /src/arch/x86/lib
parente8c866ad45d80de768c9422474449e171d133575 (diff)
ramstage: prepare for relocation
The current ramstage code contains uses of symbols that cause issues when the ramstage is relocatable. There are 2 scenarios resolved by this patch: 1. Absolute symbols that are actually sizes/limits. The symbols are problematic when relocating a program because there is no way to distinguish a symbol that shouldn't be relocated and one that can. The only way to handle these symbols is to write a program to post process the relocations and keep a whitelist of ones that shouldn't be relocated. I don't believe that is a route that should be taken so fix the users of these sizes/limits encoded as absolute symbols to calculate the size at runtime or dereference a variable in memory containing the size/limit. 2. Absoulte symbols that were relocated to a fixed address. These absolute symbols are generated by assembly files to be placed at a fixed location. Again, these symbols are problematic because one can't distinguish a symbol that can't be relocated. The symbols are again resolved at runtime to allow for proper relocation. For the symbols defining a size either use 2 symbols and calculate the difference or provide a variable in memory containing the size. Change-Id: I1ef2bfe6fd531308218bcaac5dcccabf8edf932c Signed-off-by: Aaron Durbin <adurbin@chromium.org> Reviewed-on: http://review.coreboot.org/2789 Tested-by: build bot (Jenkins) Reviewed-by: Marc Jones <marc.jones@se-eng.com>
Diffstat (limited to 'src/arch/x86/lib')
-rw-r--r--src/arch/x86/lib/c_start.S5
1 files changed, 2 insertions, 3 deletions
diff --git a/src/arch/x86/lib/c_start.S b/src/arch/x86/lib/c_start.S
index 35bc26b789..762aa8c264 100644
--- a/src/arch/x86/lib/c_start.S
+++ b/src/arch/x86/lib/c_start.S
@@ -250,11 +250,10 @@ gdb_stub_breakpoint:
#endif
- .globl gdt, gdt_end, gdt_limit, idtarg
+ .globl gdt, gdt_end, idtarg
-gdt_limit = gdt_end - gdt - 1 /* compute the table limit */
gdtaddr:
- .word gdt_limit
+ .word gdt_end - gdt - 1
.long gdt /* we know the offset */
.data