From a146d58ca0375a12f23dc5a4bd25adfa3423114f Mon Sep 17 00:00:00 2001 From: Aaron Durbin Date: Fri, 8 Feb 2013 16:56:51 -0600 Subject: 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 Reviewed-on: http://review.coreboot.org/2789 Tested-by: build bot (Jenkins) Reviewed-by: Marc Jones --- src/arch/x86/lib/c_start.S | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) (limited to 'src/arch/x86/lib') 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 -- cgit v1.2.3