arm64: defer __va translation of initrd_start and initrd_end

Before deferring the assignment of memstart_addr in a subsequent patch, to
the moment where all memory has been discovered and possibly clipped based
on the size of the linear region and the presence of a mem= command line
parameter, we need to ensure that memstart_addr is not used to perform __va
translations before it is assigned.

One such use is in the generic early DT discovery of the initrd location,
which is recorded as a virtual address in the globals initrd_start and
initrd_end. So wire up the generic support to declare the initrd addresses,
and implement it without __va() translations, and perform the translation
after memstart_addr has been assigned.

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h
index 4388651..18b7e77 100644
--- a/arch/arm64/include/asm/memory.h
+++ b/arch/arm64/include/asm/memory.h
@@ -121,6 +121,14 @@
 #define IOREMAP_MAX_ORDER	(PMD_SHIFT)
 #endif
 
+#ifdef CONFIG_BLK_DEV_INITRD
+#define __early_init_dt_declare_initrd(__start, __end)			\
+	do {								\
+		initrd_start = (__start);				\
+		initrd_end = (__end);					\
+	} while (0)
+#endif
+
 #ifndef __ASSEMBLY__
 
 extern phys_addr_t		memstart_addr;