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>
diff --git a/src/device/oprom/realmode/x86.h b/src/device/oprom/realmode/x86.h
index 76d3e46..a811a56 100644
--- a/src/device/oprom/realmode/x86.h
+++ b/src/device/oprom/realmode/x86.h
@@ -32,10 +32,10 @@
void x86_exception(struct eregs *info);
/* From x86_asm.S */
-extern unsigned char __idt_handler, __idt_handler_size;
-extern unsigned char __realmode_code, __realmode_code_size;
-extern unsigned char __realmode_call, __realmode_interrupt;
-extern unsigned char __buffer;
+extern unsigned char __idt_handler;
+extern unsigned int __idt_handler_size;
+extern unsigned char __realmode_code;
+extern unsigned int __realmode_code_size;
extern void (*realmode_call)(u32 addr, u32 eax, u32 ebx, u32 ecx, u32 edx,
u32 esi, u32 edi) asmlinkage;