Change in coreboot[master]: arch/x86/walkcbfs.S: Fix the cbfs base addr for some fmap

[Patrick Georgi (Code Review)]

Patrick Georgi has submitted this change. ( https://review.coreboot.org/c/coreboot/+/55452 )

Change subject: arch/x86/walkcbfs.S: Fix the cbfs base addr for some fmap
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arch/x86/walkcbfs.S: Fix the cbfs base addr for some fmap

Defining the memory mapped base in fmap for example "FLASH@0xff800000
0x80000" for a 8M flash is optional in fmap files. This will also
reflect in the generated fmap_config.h. Fix the assembly cbfs walker
walkcbfs.S for fmap lacking a definition of the flash base.

Change-Id: I96b18f675e625abee503648ffdc6031978a4269a
Signed-off-by: Arthur Heymans 
Reviewed-on: https://review.coreboot.org/c/coreboot/+/55452
Tested-by: build bot (Jenkins) 
Reviewed-by: Michał Żygowski 
---
M src/arch/x86/walkcbfs.S
1 file changed, 7 insertions(+), 1 deletion(-)

Approvals:
  build bot (Jenkins): Verified
  Michał Żygowski: Looks good to me, approved

diff --git a/src/arch/x86/walkcbfs.S b/src/arch/x86/walkcbfs.S
index 4608e2c..208a128 100644
--- a/src/arch/x86/walkcbfs.S
+++ b/src/arch/x86/walkcbfs.S
@@ -13,6 +13,12 @@

#define CBFS_FILE_STRUCTSIZE (CBFS_FILE_OFFSET + 4)

+#if FMAP_SECTION_COREBOOT_START < (0xffffffff - CONFIG_ROM_SIZE + 1)
+#define COREBOOT_CBFS_START (0xffffffff - CONFIG_ROM_SIZE + 1 + FMAP_SECTION_COREBOOT_START)
+#else
+#define COREBOOT_CBFS_START FMAP_SECTION_COREBOOT_START
+#endif
+
 .code32
 .section .init
 .global walkcbfs_asm
@@ -26,7 +32,7 @@
 walkcbfs_asm:
    cld

-	movl $FMAP_SECTION_COREBOOT_START, %ebx
+	movl $COREBOOT_CBFS_START, %ebx

/* determine filename length */
    mov $0, %eax