x86: Support writing configuration tables in high area

For those secondary bootloaders like SeaBIOS who want to live in
the F segment, which conflicts the configuration table address,
now we allow write_tables() to write the configuration tables in
high area (malloc'ed memory).

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/arch/x86/lib/tables.c b/arch/x86/lib/tables.c
index 9f0d928..eccef8a 100644
--- a/arch/x86/lib/tables.c
+++ b/arch/x86/lib/tables.c
@@ -67,11 +67,22 @@
 {
 	u32 rom_table_start = ROM_TABLE_ADDR;
 	u32 rom_table_end;
+	u32 high_table, table_size;
 	int i;
 
 	for (i = 0; i < ARRAY_SIZE(table_write_funcs); i++) {
 		rom_table_end = table_write_funcs[i](rom_table_start);
 		rom_table_end = ALIGN(rom_table_end, ROM_TABLE_ALIGN);
+
+		table_size = rom_table_end - rom_table_start;
+		high_table = (u32)memalign(ROM_TABLE_ALIGN, table_size);
+		if (high_table) {
+			memset((void *)high_table, 0, table_size);
+			table_write_funcs[i](high_table);
+		} else {
+			printf("%d: no memory for configuration tables\n", i);
+		}
+
 		rom_table_start = rom_table_end;
 	}
 }