diff --git a/linux-2.6.24-rc7/drivers/ata/libata-core.c 
b/linux-2.6.24-rc7-twam/drivers/ata/libata-core.c
index 4753a18..ac5a0d4 100644
--- a/linux-2.6.24-rc7/drivers/ata/libata-core.c
+++ b/linux-2.6.24-rc7-twam/drivers/ata/libata-core.c
@@ -119,6 +119,10 @@ int libata_noacpi = 0;
 module_param_named(noacpi, libata_noacpi, int, 0444);
 MODULE_PARM_DESC(noacpi, "Disables the use of ACPI in probe/suspend/resume when set");
 
+int libata_force_cbl = 0;
+module_param_named(force_cbl, libata_force_cbl, int, 0644);
+MODULE_PARM_DESC(force_cbl, "force PATA cable type (0=keep, 40=40c, 80=80c)");
+
 MODULE_AUTHOR("Jeff Garzik");
 MODULE_DESCRIPTION("Library module for ATA devices");
 MODULE_LICENSE("GPL");
@@ -4318,16 +4322,29 @@ static void ata_dev_xfermask(struct ata_device *dev)
 	 * drive side as well. Cases where we know a 40wire cable
 	 * is used safely for 80 are not checked here.
 	 */
-	if (xfer_mask & (0xF8 << ATA_SHIFT_UDMA))
-		/* UDMA/44 or higher would be available */
-		if ((ap->cbl == ATA_CBL_PATA40) ||
-		    (ata_is_40wire(dev) &&
-		    (ap->cbl == ATA_CBL_PATA_UNK ||
-		     ap->cbl == ATA_CBL_PATA80))) {
-			ata_dev_printk(dev, KERN_WARNING,
-				 "limited to UDMA/33 due to 40-wire cable\n");
-			xfer_mask &= ~(0xF8 << ATA_SHIFT_UDMA);
+       if (xfer_mask & (0xF8 << ATA_SHIFT_UDMA)) {
+                switch (libata_force_cbl) {
+                        case 40:
+                               /* limit to UDMA/33 */
+                                ata_dev_printk(dev, KERN_INFO, "forcing 40c\n");
+                               xfer_mask &= ~(0xF8 << ATA_SHIFT_UDMA);
+                               break;
+                        case 80:
+                               /* ignore cable checks */
+                                ata_dev_printk(dev, KERN_INFO, "forcing 80c\n");
+                               break;
+                       default:
+                               /* UDMA/44 or higher would be available */
+                               if ((ap->cbl == ATA_CBL_PATA40) ||
+                                   (ata_is_40wire(dev) &&
+                                   (ap->cbl == ATA_CBL_PATA_UNK ||
+                                    ap->cbl == ATA_CBL_PATA80))) {
+                                       ata_dev_printk(dev, KERN_WARNING,
+                                                "limited to UDMA/33 due to 40-wire cable\n");
+                                       xfer_mask &= ~(0xF8 << ATA_SHIFT_UDMA);
+                               }
 		}
+       }
 
 	ata_unpack_xfermask(xfer_mask, &dev->pio_mask,
 			    &dev->mwdma_mask, &dev->udma_mask);
diff --git a/linux-2.6.24-rc7/drivers/ata/libata-eh.c 
b/linux-2.6.24-rc7-twam/drivers/ata/libata-eh.c
index f0124a8..7c607e0 100644
--- a/linux-2.6.24-rc7/drivers/ata/libata-eh.c
+++ b/linux-2.6.24-rc7-twam/drivers/ata/libata-eh.c
@@ -2288,9 +2288,27 @@ static int ata_eh_revalidate_and_attach(struct ata_link *link,
 
 	/* PDIAG- should have been released, ask cable type if post-reset */
 	if (ata_is_host_link(link) && ap->ops->cable_detect &&
-	    (ehc->i.flags & ATA_EHI_DID_RESET))
+	    (ehc->i.flags & ATA_EHI_DID_RESET)) {
 		ap->cbl = ap->ops->cable_detect(ap);
 
+               if (!(ap->flags & ATA_FLAG_SATA) && libata_force_cbl) {
+                       switch (libata_force_cbl) {
+                       case 40:
+                               ata_port_printk(ap, KERN_INFO, "forcing 40c\n");
+                               ap->cbl = ATA_CBL_PATA40;
+                               break;
+                       case 80:
+                               ata_port_printk(ap, KERN_INFO, "forcing 80c\n");
+                               ap->cbl = ATA_CBL_PATA80;
+                               break;
+                       default:
+                               ata_port_printk(ap, KERN_WARNING,
+                                               "invalid force_cbl value %d\n",
+                                               libata_force_cbl);
+                       }
+               }
+       }
+
 	/* Configure new devices forward such that user doesn't see
 	 * device detection messages backwards.
 	 */
diff --git a/linux-2.6.24-rc7/drivers/ata/libata.h 
b/linux-2.6.24-rc7-twam/drivers/ata/libata.h
index bbe59c2..b990a8d 100644
--- a/linux-2.6.24-rc7/drivers/ata/libata.h
+++ b/linux-2.6.24-rc7-twam/drivers/ata/libata.h
@@ -60,6 +60,7 @@ extern int atapi_dmadir;
 extern int atapi_passthru16;
 extern int libata_fua;
 extern int libata_noacpi;
+extern int libata_force_cbl;
 extern struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev);
 extern int ata_build_rw_tf(struct ata_taskfile *tf, struct ata_device *dev,
                           u64 block, u32 n_block, unsigned int tf_flags,