diff --git a/drivers/ide/ide-generic.c b/drivers/ide/ide-generic.c
index 8fe8b5b..0a3cb0c 100644
--- a/drivers/ide/ide-generic.c
+++ b/drivers/ide/ide-generic.c
@@ -19,6 +19,7 @@
 #include <linux/init.h>
 #include <linux/module.h>
 #include <linux/ide.h>
+#include <linux/pci_ids.h>
 
 /* FIXME: convert m32r to use ide_platform host driver */
 #ifdef CONFIG_M32R
@@ -27,7 +28,7 @@
 
 #define DRV_NAME	"ide_generic"
 
-static int probe_mask = 0x03;
+static int probe_mask;
 module_param(probe_mask, int, 0);
 MODULE_PARM_DESC(probe_mask, "probe mask for legacy ISA IDE ports");
 
@@ -100,19 +101,65 @@
 static const int legacy_irqs[]  = { 14, 15, 11, 10, 8, 12 };
 #endif
 
+static void ide_generic_check_pci_legacy_iobases(int *primary, int *secondary)
+{
+	struct pci_dev *p = NULL;
+	u16 val;
+
+	for_each_pci_dev(p) {
+
+		if (pci_resource_start(p, 0) == 0x1f0)
+			*primary = 1;
+		if (pci_resource_start(p, 2) == 0x170)
+			*secondary = 1;
+
+		/* Cyrix CS55{1,2}0 pre SFF MWDMA ATA on the bridge */
+		if (p->vendor == PCI_VENDOR_ID_CYRIX &&
+		    (p->device == PCI_DEVICE_ID_CYRIX_5510 ||
+		     p->device == PCI_DEVICE_ID_CYRIX_5520))
+			*primary = *secondary = 1;
+
+		/* Intel MPIIX - PIO ATA on non PCI side of bridge */
+		if (p->vendor == PCI_VENDOR_ID_INTEL &&
+		    p->device == PCI_DEVICE_ID_INTEL_82371MX) {
+
+			pci_read_config_word(p, 0x6C, &val);
+			if (val & 0x8000) {
+				/* ATA port enabled */
+				if (val & 0x4000)
+					*secondary = 1;
+				else
+					*primary = 1;
+			}
+		}
+	}
+}
+
 static int __init ide_generic_init(void)
 {
 	hw_regs_t hw[MAX_HWIFS], *hws[MAX_HWIFS];
 	struct ide_host *host;
 	unsigned long io_addr;
-	int i, rc;
+	int i, rc, primary = 0, secondary = 0;
 
 #ifdef CONFIG_MIPS
 	if (!ide_probe_legacy())
 		return -ENODEV;
 #endif
-	printk(KERN_INFO DRV_NAME ": please use \"probe_mask=0x3f\" module "
-			 "parameter for probing all legacy ISA IDE ports\n");
+	ide_generic_check_pci_legacy_iobases(&primary, &secondary);
+
+	if (!probe_mask) {
+		printk(KERN_INFO DRV_NAME ": please use \"probe_mask=0x3f\" "
+		     "module parameter for probing all legacy ISA IDE ports\n");
+
+		if (primary == 0)
+			probe_mask |= 0x1;
+
+		if (secondary == 0)
+			probe_mask |= 0x2;
+	} else
+		printk(KERN_INFO DRV_NAME ": enforcing probing of I/O ports "
+			"upon user request\n");
 
 	memset(hws, 0, sizeof(hw_regs_t *) * MAX_HWIFS);