diff --git a/arch/mips/tx4938/toshiba_rbtx4938/setup.c b/arch/mips/tx4938/toshiba_rbtx4938/setup.c
index 5c7ace9..a96d442 100644
--- a/arch/mips/tx4938/toshiba_rbtx4938/setup.c
+++ b/arch/mips/tx4938/toshiba_rbtx4938/setup.c
@@ -918,7 +918,7 @@ void __init toshiba_rbtx4938_setup(void)
 	TX4938_WR(0xff1ff414, 0x00000000);	/* h/w flow control off */
 
 #ifndef CONFIG_PCI
-	set_io_port_base(RBTX4938_ETHER_BASE);
+	set_io_port_base(KSEG1);
 #endif
 
 #ifdef CONFIG_SERIAL_TXX9