}
 }
 
+static bool ahci_broken_system_poweroff(struct pci_dev *pdev)
+{
+       static const struct dmi_system_id broken_systems[] = {
+               {
+                       .ident = "HP Compaq nx6310",
+                       .matches = {
+                               DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
+                               DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq nx6310"),
+                       },
+                       /* PCI slot number of the controller */
+                       .driver_data = (void *)0x1FUL,
+               },
+
+               { }     /* terminate list */
+       };
+       const struct dmi_system_id *dmi = dmi_first_match(broken_systems);
+
+       if (dmi) {
+               unsigned long slot = (unsigned long)dmi->driver_data;
+               /* apply the quirk only to on-board controllers */
+               return slot == PCI_SLOT(pdev->devfn);
+       }
+
+       return false;
+}
+
 static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 {
        static int printed_version;
                }
        }
 
+       if (ahci_broken_system_poweroff(pdev)) {
+               pi.flags |= ATA_FLAG_NO_POWEROFF_SPINDOWN;
+               dev_info(&pdev->dev,
+                       "quirky BIOS, skipping spindown on poweroff\n");
+       }
+
        /* CAP.NP sometimes indicate the index of the last enabled
         * port, at other times, that of the last possible port, so
         * determining the maximum port number requires looking at