diff --git a/drivers/ata/ata_piix.c b/drivers/ata/ata_piix.c index 22752e46b34f..0ff96a06374e 100644 --- a/drivers/ata/ata_piix.c +++ b/drivers/ata/ata_piix.c @@ -1173,6 +1173,39 @@ static void __devinit piix_init_sata_map(struct pci_dev *pdev, hpriv->map = map; } +static void piix_iocfg_bit18_quirk(struct pci_dev *pdev) +{ + static struct dmi_system_id sysids[] = { + { + /* Clevo M570U sets IOCFG bit 18 if the cdrom + * isn't used to boot the system which + * disables the channel. + */ + .ident = "M570U", + .matches = { + DMI_MATCH(DMI_SYS_VENDOR, "Clevo Co."), + DMI_MATCH(DMI_PRODUCT_NAME, "M570U"), + }, + }, + }; + u32 iocfg; + + if (!dmi_check_system(sysids)) + return; + + /* The datasheet says that bit 18 is NOOP but certain systems + * seem to use it to disable a channel. Clear the bit on the + * affected systems. + */ + pci_read_config_dword(pdev, PIIX_IOCFG, &iocfg); + if (iocfg & (1 << 18)) { + dev_printk(KERN_INFO, &pdev->dev, + "applying IOCFG bit18 quirk\n"); + iocfg &= ~(1 << 18); + pci_write_config_dword(pdev, PIIX_IOCFG, iocfg); + } +} + /** * piix_init_one - Register PIIX ATA PCI device with kernel services * @pdev: PCI device to register @@ -1234,6 +1267,9 @@ static int piix_init_one (struct pci_dev *pdev, const struct pci_device_id *ent) piix_map_db_table[ent->driver_data]); } + /* apply IOCFG bit18 quirk */ + piix_iocfg_bit18_quirk(pdev); + /* On ICH5, some BIOSen disable the interrupt using the * PCI_COMMAND_INTX_DISABLE bit added in PCI 2.3. * On ICH6, this bit has the same effect, but only when