diff options
author | Tejun Heo <htejun@gmail.com> | 2007-10-09 15:02:23 +0900 |
---|---|---|
committer | Jeff Garzik <jeff@garzik.org> | 2007-10-12 14:55:47 -0400 |
commit | 5f226c6bf78edab023ed1ea679531731d9df92a6 (patch) | |
tree | 01e0dff1224476aa52c240ee958ec7948bb85cc6 /drivers/ata | |
parent | 1c954a4d9a9e351fa3509533fd8dd5f3821206cd (diff) | |
download | lwn-5f226c6bf78edab023ed1ea679531731d9df92a6.tar.gz lwn-5f226c6bf78edab023ed1ea679531731d9df92a6.zip |
ahci: fix notification handling
Asynchronous notification on ICH9 didn't work because it didn't write
AN FIS into the RX area - it only updates SNotification. Also,
snooping SDB_FIS RX area is racy against further SDB FIS receptions.
Let sata_async_notification() determine using SNTF if it's available
and snoop RX area iff SNTF isn't available
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Kristen Carlson Accardi <kristen.c.accardi@intel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Diffstat (limited to 'drivers/ata')
-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 6633c7422fc4..abfb72aae3de 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 */ |