diff --git a/sys/arm/arm/genassym.c b/sys/arm/arm/genassym.c
index 7132423686d..ab7ec0f6636 100644
--- a/sys/arm/arm/genassym.c
+++ b/sys/arm/arm/genassym.c
@@ -161,3 +161,12 @@ ASSYM(DCACHE_LINE_SIZE, offsetof(struct cpuinfo, dcache_line_size));
 ASSYM(DCACHE_LINE_MASK, offsetof(struct cpuinfo, dcache_line_mask));
 ASSYM(ICACHE_LINE_SIZE, offsetof(struct cpuinfo, icache_line_size));
 ASSYM(ICACHE_LINE_MASK, offsetof(struct cpuinfo, icache_line_mask));
+
+/*
+ * Emit the LOCORE_MAP_MB option as a #define only if the option was set.
+ */
+#include "opt_locore.h"
+
+#ifdef LOCORE_MAP_MB
+ASSYM(LOCORE_MAP_MB, LOCORE_MAP_MB);
+#endif
diff --git a/sys/arm/arm/locore-v6.S b/sys/arm/arm/locore-v6.S
index ef96c61a8fe..04858426ba3 100644
--- a/sys/arm/arm/locore-v6.S
+++ b/sys/arm/arm/locore-v6.S
@@ -38,6 +38,11 @@
 
 __FBSDID("$FreeBSD$");
 
+/* We map 64MB of kernel unless overridden in assym.s by the kernel option. */
+#ifndef LOCORE_MAP_MB
+#define	LOCORE_MAP_MB	64
+#endif
+
 #if __ARM_ARCH >= 7
 #if defined(__ARM_ARCH_7VE__) || defined(__clang__)
 /*
@@ -176,12 +181,13 @@ ASENTRY_NP(_start)
 	bl	build_pagetables
 
 	/* 
-	 * Next we do 64MiB starting at the physical load address, mapped to
-	 * the VA the kernel is linked for.
+	 * Next we map the kernel starting at the physical load address, mapped
+	 * to the VA the kernel is linked for.  The default size we map is 64MiB
+	 * but it can be overridden with a kernel option.
 	 */
 	mov	r1, r5
 	ldr	r2, =(KERNVIRTADDR)
-	mov	r3, #64
+	ldr	r3, =(LOCORE_MAP_MB)
 	bl	build_pagetables
 
 	/* Create a device mapping for early_printf if specified. */
diff --git a/sys/conf/options.arm b/sys/conf/options.arm
index 91ca74b8edb..3f91b2896e5 100644
--- a/sys/conf/options.arm
+++ b/sys/conf/options.arm
@@ -35,6 +35,7 @@ KERNBASE		opt_global.h
 KERNVIRTADDR		opt_global.h
 LINUX_BOOT_ABI		opt_global.h
 LOADERRAMADDR		opt_global.h
+LOCORE_MAP_MB		opt_locore.h
 NKPT2PG			opt_pmap.h
 PHYSADDR		opt_global.h
 PLATFORM		opt_global.h