diff -Nurb linux/arch/mips/au1000/mtx-1/board_setup.c /home/br1/linux-idsel/arch/mips/au1000/mtx-1/board_setup.c
--- linux/arch/mips/au1000/mtx-1/board_setup.c	2005-08-18 18:23:59.000000000 +0200
+++ /home/br1/linux-idsel/arch/mips/au1000/mtx-1/board_setup.c	2005-08-18 18:19:48.000000000 +0200
@@ -48,6 +48,10 @@
 
 extern struct rtc_ops no_rtc_ops;
 
+extern int (*board_pci_idsel)(unsigned int devsel, int assert);
+int	mtx1_pci_idsel(unsigned int devsel, int assert);
+
+
 void board_reset (void)
 {
 	/* Hit BCSR.SYSTEM_CONTROL[SW_RST] */
@@ -85,11 +89,39 @@
 	au_writel( 0xFFFFFFFF, SYS_TRIOUTCLR );
 	au_writel( 0x00000001, SYS_OUTPUTCLR ); // set M66EN (PCI 66MHz) to OFF
 	au_writel( 0x00000008, SYS_OUTPUTSET ); // set PCI CLKRUN# to OFF
+	au_writel( 0x00000002, SYS_OUTPUTSET ); // set EXT_IO3 ON
 	au_writel( 0x00000020, SYS_OUTPUTCLR ); // set eth PHY TX_ER to OFF
 
 	// enable LED and set it to green
 	au_writel( au_readl(GPIO2_DIR) | 0x1800, GPIO2_DIR );
 	au_writel( 0x18000800, GPIO2_OUTPUT );
 
+	board_pci_idsel = mtx1_pci_idsel;
+
 	printk("4G Systems MTX-1 Board\n");
 }
+
+
+/* 
+ */
+int
+mtx1_pci_idsel(unsigned int devsel, int assert)
+{
+#define MTX_IDSEL_ONLY_0_AND_3 0
+#if MTX_IDSEL_ONLY_0_AND_3
+	if (devsel != 0 && devsel != 3) {
+		printk("*** not 0 or 3\n");
+		return 0;
+	}
+#endif
+
+	if (assert && devsel != 0) {
+		// supress signal to cardbus
+		au_writel( 0x00000002, SYS_OUTPUTCLR ); // set EXT_IO3 OFF
+	}
+	else {
+		au_writel( 0x00000002, SYS_OUTPUTSET ); // set EXT_IO3 ON
+	}
+	au_sync_udelay(1);
+	return 1;
+}
diff -Nurb linux/arch/mips/au1000/mtx-1/irqmap.c /home/br1/linux-idsel/arch/mips/au1000/mtx-1/irqmap.c
--- linux/arch/mips/au1000/mtx-1/irqmap.c	2005-08-18 18:24:05.000000000 +0200
+++ /home/br1/linux-idsel/arch/mips/au1000/mtx-1/irqmap.c	2005-08-16 16:37:39.000000000 +0200
@@ -73,7 +73,7 @@
 	 *	A       B       C       D
 	 */
 	{
-		{INTA, INTB, INTX, INTX},   /* IDSEL 0 */
+		{INTA, INTA, INTX, INTX},   /* IDSEL 0 */
 		{INTB, INTA, INTX, INTX},   /* IDSEL 1 */
 		{INTC, INTD, INTX, INTX},   /* IDSEL 2 */
 		{INTD, INTC, INTX, INTX},   /* IDSEL 3 */