x86: Ignore memory >4GB when parsing Coreboot tables

U-boot is unable to actually use that memory and it can
cause problems with relocation if it tries to.

Signed-off-by: Duncan Laurie <dlaurie@chromium.org>
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/x86/cpu/coreboot/sdram.c b/arch/x86/cpu/coreboot/sdram.c
index 93dccb8..5d3da99 100644
--- a/arch/x86/cpu/coreboot/sdram.c
+++ b/arch/x86/cpu/coreboot/sdram.c
@@ -60,6 +60,10 @@
 		struct memrange *memrange = &lib_sysinfo.memrange[i];
 		unsigned long long end = memrange->base + memrange->size;
 
+		/* Ignore memory over 4GB, we can't use it. */
+		if (memrange->base > 0xffffffff)
+			continue;
+
 		if (memrange->type == CB_MEM_RAM && end > ram_size)
 			ram_size = end;
 	}