Index: sys/compat/linuxkpi/common/include/linux/io.h
===================================================================
--- sys/compat/linuxkpi/common/include/linux/io.h
+++ sys/compat/linuxkpi/common/include/linux/io.h
@@ -364,8 +364,14 @@
     _ioremap_attr((addr), (size), VM_MEMATTR_WRITE_BACK)
 #define	ioremap_wt(addr, size)						\
     _ioremap_attr((addr), (size), VM_MEMATTR_WRITE_THROUGH)
+#ifdef VM_MEMATTR_DEVICE
+// on aarch64, it's really important to map as DEVICE, otherwise expect freezes
+#define	ioremap(addr, size)						\
+    _ioremap_attr((addr), (size), VM_MEMATTR_DEVICE)
+#else
 #define	ioremap(addr, size)						\
     _ioremap_attr((addr), (size), VM_MEMATTR_UNCACHEABLE)
+#endif
 void iounmap(void *addr);
 
 #define	memset_io(a, b, c)	memset((a), (b), (c))