From f1a58ecae527fc67c87ce4dcb9e73894f64aadfe Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Sun, 20 Aug 2006 17:56:38 +0900 Subject: [PATCH] [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: Tejun Heo Signed-off-by: Jeff Garzik --- drivers/scsi/ata_piix.c | 60 +++++++++++++++++++++++++++++++++++-------------- 1 file changed, 43 insertions(+), 17 deletions(-) diff --git a/drivers/scsi/ata_piix.c b/drivers/scsi/ata_piix.c index 5e8afc8..01b3530 100644 --- a/drivers/scsi/ata_piix.c +++ b/drivers/scsi/ata_piix.c @@ -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 * - * Reads and configures SATA PCI device's PCI config register - * Port Configuration and Status (PCS) to determine port and - * device availability. Return -ENODEV to skip reset if no - * device is present. + * Reads SATA PCI device's PCI config register Port Configuration + * and Status (PCS) to determine port and device availability. * * LOCKING: * None (inherited from caller). * * 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 piix_host_priv *hpriv = ap->host_set->private_data; const unsigned int *map = hpriv->map; int base = 2 * ap->hard_port_no; - unsigned int present = 0; + unsigned int present_mask = 0; int port, i; u16 pcs; @@ -564,24 +562,52 @@ static int piix_sata_prereset(struct ata_port *ap) continue; if ((ap->flags & PIIX_FLAG_IGNORE_PCS) || (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", - ap->id, pcs, present); + DPRINTK("ata%u: LEAVE, pcs=0x%x present_mask=0x%x\n", + ap->id, pcs, present_mask); - if (!present) { - ata_port_printk(ap, KERN_INFO, "SATA port has no device.\n"); - ap->eh_context.i.action &= ~ATA_EH_RESET_MASK; - return 0; + return present_mask; +} + +/** + * 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) { - 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); } -- 2.7.4