Commit f1a58eca authored by Tejun Heo's avatar Tejun Heo Committed by Jeff Garzik

[PATCH] ata_piix: fix ghost device probing by honoring PCS present bits

Move out PCS handling from piix_sata_prereset() into
piix_sata_present_mask() and use it from newly implemented
piix_sata_softreset().  Class codes for devices which are indicated to
be absent by PCS are cleared to ATA_DEV_NONE.  This fixes ghost device
problem reported on ICH6 and 7.

This patch moves PCS handling from prereset to softreset, which makes
two behavior changes.

* perform softreset even when PCS indicates no device
* PCS handling is repeated before retrying softresets due to reset
  failures.

Both behavior changes are intended and more consistent with how other
drivers behave.
Signed-off-by: default avatarTejun Heo <htejun@gmail.com>
Signed-off-by: default avatarJeff Garzik <jeff@garzik.org>
parent d14b50cc
...@@ -531,27 +531,25 @@ static void piix_pata_error_handler(struct ata_port *ap) ...@@ -531,27 +531,25 @@ static void piix_pata_error_handler(struct ata_port *ap)
} }
/** /**
* piix_sata_prereset - prereset for SATA host controller * piix_sata_present_mask - determine present mask for SATA host controller
* @ap: Target port * @ap: Target port
* *
* Reads and configures SATA PCI device's PCI config register * Reads SATA PCI device's PCI config register Port Configuration
* Port Configuration and Status (PCS) to determine port and * and Status (PCS) to determine port and device availability.
* device availability. Return -ENODEV to skip reset if no
* device is present.
* *
* LOCKING: * LOCKING:
* None (inherited from caller). * None (inherited from caller).
* *
* RETURNS: * RETURNS:
* 0 if device is present, -ENODEV otherwise. * determined present_mask
*/ */
static int piix_sata_prereset(struct ata_port *ap) static unsigned int piix_sata_present_mask(struct ata_port *ap)
{ {
struct pci_dev *pdev = to_pci_dev(ap->host_set->dev); struct pci_dev *pdev = to_pci_dev(ap->host_set->dev);
struct piix_host_priv *hpriv = ap->host_set->private_data; struct piix_host_priv *hpriv = ap->host_set->private_data;
const unsigned int *map = hpriv->map; const unsigned int *map = hpriv->map;
int base = 2 * ap->hard_port_no; int base = 2 * ap->hard_port_no;
unsigned int present = 0; unsigned int present_mask = 0;
int port, i; int port, i;
u16 pcs; u16 pcs;
...@@ -564,24 +562,52 @@ static int piix_sata_prereset(struct ata_port *ap) ...@@ -564,24 +562,52 @@ static int piix_sata_prereset(struct ata_port *ap)
continue; continue;
if ((ap->flags & PIIX_FLAG_IGNORE_PCS) || if ((ap->flags & PIIX_FLAG_IGNORE_PCS) ||
(pcs & 1 << (hpriv->map_db->present_shift + port))) (pcs & 1 << (hpriv->map_db->present_shift + port)))
present = 1; present_mask |= 1 << i;
} }
DPRINTK("ata%u: LEAVE, pcs=0x%x present=0x%x\n", DPRINTK("ata%u: LEAVE, pcs=0x%x present_mask=0x%x\n",
ap->id, pcs, present); ap->id, pcs, present_mask);
if (!present) { return present_mask;
ata_port_printk(ap, KERN_INFO, "SATA port has no device.\n"); }
ap->eh_context.i.action &= ~ATA_EH_RESET_MASK;
return 0; /**
* piix_sata_softreset - reset SATA host port via ATA SRST
* @ap: port to reset
* @classes: resulting classes of attached devices
*
* Reset SATA host port via ATA SRST. On controllers with
* reliable PCS present bits, the bits are used to determine
* device presence.
*
* LOCKING:
* Kernel thread context (may sleep)
*
* RETURNS:
* 0 on success, -errno otherwise.
*/
static int piix_sata_softreset(struct ata_port *ap, unsigned int *classes)
{
unsigned int present_mask;
int i, rc;
present_mask = piix_sata_present_mask(ap);
rc = ata_std_softreset(ap, classes);
if (rc)
return rc;
for (i = 0; i < ATA_MAX_DEVICES; i++) {
if (!(present_mask & (1 << i)))
classes[i] = ATA_DEV_NONE;
} }
return ata_std_prereset(ap); return 0;
} }
static void piix_sata_error_handler(struct ata_port *ap) static void piix_sata_error_handler(struct ata_port *ap)
{ {
ata_bmdma_drive_eh(ap, piix_sata_prereset, ata_std_softreset, NULL, ata_bmdma_drive_eh(ap, ata_std_prereset, piix_sata_softreset, NULL,
ata_std_postreset); ata_std_postreset);
} }
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment