diff --git a/atahpt.c b/atahpt.c
index 2bf4a11..de888b0 100644
--- a/atahpt.c
+++ b/atahpt.c
@@ -18,6 +18,8 @@
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
  */
 
+#if defined(__i386__) || defined(__x86_64__)
+
 #include <stdlib.h>
 #include <string.h>
 #include "flash.h"
@@ -77,3 +79,7 @@
 	OUTL((uint32_t)addr, io_base_addr + BIOS_ROM_ADDR);
 	return INB(io_base_addr + BIOS_ROM_DATA);
 }
+
+#else
+#error PCI port I/O access is not supported on this architecture yet.
+#endif
diff --git a/satamv.c b/satamv.c
index 01919d0..c057a2e 100644
--- a/satamv.c
+++ b/satamv.c
@@ -19,6 +19,7 @@
  */
 
 /* Datasheets are not public (yet?) */
+#if defined(__i386__) || defined(__x86_64__)
 
 #include <stdlib.h>
 #include "flash.h"
@@ -182,3 +183,7 @@
 {
 	return satamv_indirect_chip_readb(addr);
 }
+
+#else
+#error PCI port I/O access is not supported on this architecture yet.
+#endif