diff --git a/sys/arm64/include/pte.h b/sys/arm64/include/pte.h
--- a/sys/arm64/include/pte.h
+++ b/sys/arm64/include/pte.h
@@ -164,7 +164,11 @@
 	/* 0x2 also marks an invalid address */
 #define	L3_PAGE		0x3
 
-#define	PMAP_MAPDEV_EARLY_SIZE	(L2_SIZE * 8)
+/*
+ * A substantial portion of this is to make sure that we can cope with 4K
+ * framebuffers in early boot, assuming a common 4K resolution @ 32-bit depth.
+ */
+#define	PMAP_MAPDEV_EARLY_SIZE	(L2_SIZE * 20)
 
 #if PAGE_SIZE == PAGE_SIZE_4K
 #define	L0_ENTRIES_SHIFT 9