diff options
| -rw-r--r-- | drivers/ata/ahci.c | 30 |
1 files changed, 21 insertions, 9 deletions
diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c index 6633c7422fc..abfb72aae3d 100644 --- a/drivers/ata/ahci.c +++ b/drivers/ata/ahci.c @@ -1420,6 +1420,7 @@ static void ahci_port_intr(struct ata_port *ap) void __iomem *port_mmio = ap->ioaddr.cmd_addr; struct ata_eh_info *ehi = &ap->link.eh_info; struct ahci_port_priv *pp = ap->private_data; + struct ahci_host_priv *hpriv = ap->host->private_data; u32 status, qc_active; int rc, known_irq = 0; @@ -1432,17 +1433,28 @@ static void ahci_port_intr(struct ata_port *ap) } if (status & PORT_IRQ_SDB_FIS) { - /* If the 'N' bit in word 0 of the FIS is set, we just - * received asynchronous notification. Tell libata - * about it. Note that as the SDB FIS itself is - * accessible, SNotification can be emulated by the - * driver but don't bother for the time being. + /* If SNotification is available, leave notification + * handling to sata_async_notification(). If not, + * emulate it by snooping SDB FIS RX area. + * + * Snooping FIS RX area is probably cheaper than + * poking SNotification but some constrollers which + * implement SNotification, ICH9 for example, don't + * store AN SDB FIS into receive area. */ - const __le32 *f = pp->rx_fis + RX_FIS_SDB; - u32 f0 = le32_to_cpu(f[0]); - - if (f0 & (1 << 15)) + if (hpriv->cap & HOST_CAP_SNTF) sata_async_notification(ap); + else { + /* If the 'N' bit in word 0 of the FIS is set, + * we just received asynchronous notification. + * Tell libata about it. + */ + const __le32 *f = pp->rx_fis + RX_FIS_SDB; + u32 f0 = le32_to_cpu(f[0]); + + if (f0 & (1 << 15)) + sata_async_notification(ap); + } } /* pp->active_link is valid iff any command is in flight */ |