diff options
| -rw-r--r-- | drivers/ata/ata_piix.c | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/drivers/ata/ata_piix.c b/drivers/ata/ata_piix.c index ea2c7649d399..a9027b8fbdd5 100644 --- a/drivers/ata/ata_piix.c +++ b/drivers/ata/ata_piix.c @@ -1348,6 +1348,8 @@ static void __devinit piix_init_sidpr(struct ata_host *host) { struct pci_dev *pdev = to_pci_dev(host->dev); struct piix_host_priv *hpriv = host->private_data; + struct ata_device *dev0 = &host->ports[0]->link.device[0]; + u32 scontrol; int i; /* check for availability */ @@ -1366,6 +1368,29 @@ static void __devinit piix_init_sidpr(struct ata_host *host) return; hpriv->sidpr = pcim_iomap_table(pdev)[PIIX_SIDPR_BAR]; + + /* SCR access via SIDPR doesn't work on some configurations. + * Give it a test drive by inhibiting power save modes which + * we'll do anyway. + */ + scontrol = piix_sidpr_read(dev0, SCR_CONTROL); + + /* if IPM is already 3, SCR access is probably working. Don't + * un-inhibit power save modes as BIOS might have inhibited + * them for a reason. + */ + if ((scontrol & 0xf00) != 0x300) { + scontrol |= 0x300; + piix_sidpr_write(dev0, SCR_CONTROL, scontrol); + scontrol = piix_sidpr_read(dev0, SCR_CONTROL); + + if ((scontrol & 0xf00) != 0x300) { + dev_printk(KERN_INFO, host->dev, "SCR access via " + "SIDPR is available but doesn't work\n"); + return; + } + } + host->ports[0]->ops = &piix_sidpr_sata_ops; host->ports[1]->ops = &piix_sidpr_sata_ops; } |