1 files changed, 64 insertions, 17 deletions

diff --git a/drivers/scsi/ata_piix.c b/drivers/scsi/ata_piix.c
index 19745a31072b..2d20caf377f5 100644
--- a/drivers/scsi/ata_piix.c
+++ b/drivers/scsi/ata_piix.c
@@ -390,7 +390,8 @@ static struct ata_port_info piix_port_info[] = {
         /* ich5_sata */
         {
                 .sht            = &piix_sht,
-                .host_flags     = ATA_FLAG_SATA | PIIX_FLAG_CHECKINTR,
+                .host_flags     = ATA_FLAG_SATA | PIIX_FLAG_CHECKINTR |
+                                  PIIX_FLAG_IGNORE_PCS,
                 .pio_mask       = 0x1f, /* pio0-4 */
                 .mwdma_mask     = 0x07, /* mwdma0-2 */
                 .udma_mask      = 0x7f, /* udma0-6 */
@@ -467,6 +468,11 @@ MODULE_LICENSE("GPL");
 MODULE_DEVICE_TABLE(pci, piix_pci_tbl);
 MODULE_VERSION(DRV_VERSION);
 
+static int force_pcs = 0;
+module_param(force_pcs, int, 0444);
+MODULE_PARM_DESC(force_pcs, "force honoring or ignoring PCS to work around "
+                 "device mis-detection (0=default, 1=ignore PCS, 2=honor PCS)");
+
 /**
  *      piix_pata_cbl_detect - Probe host controller cable detect info
  *      @ap: Port for which cable detect info is desired
@@ -531,27 +537,25 @@ 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 +568,52 @@ 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_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);
 }
 
@@ -785,6 +817,7 @@ static int __devinit piix_check_450nx_errata(struct pci_dev *ata_dev)
 }
 
 static void __devinit piix_init_pcs(struct pci_dev *pdev,
+                                    struct ata_port_info *pinfo,
                                     const struct piix_map_db *map_db)
 {
         u16 pcs, new_pcs;
@@ -798,6 +831,18 @@ static void __devinit piix_init_pcs(struct pci_dev *pdev,
                 pci_write_config_word(pdev, ICH5_PCS, new_pcs);
                 msleep(150);
         }
+
+        if (force_pcs == 1) {
+                dev_printk(KERN_INFO, &pdev->dev,
+                           "force ignoring PCS (0x%x)\n", new_pcs);
+                pinfo[0].host_flags |= PIIX_FLAG_IGNORE_PCS;
+                pinfo[1].host_flags |= PIIX_FLAG_IGNORE_PCS;
+        } else if (force_pcs == 2) {
+                dev_printk(KERN_INFO, &pdev->dev,
+                           "force honoring PCS (0x%x)\n", new_pcs);
+                pinfo[0].host_flags &= ~PIIX_FLAG_IGNORE_PCS;
+                pinfo[1].host_flags &= ~PIIX_FLAG_IGNORE_PCS;
+        }
 }
 
 static void __devinit piix_init_sata_map(struct pci_dev *pdev,
@@ -828,6 +873,7 @@ static void __devinit piix_init_sata_map(struct pci_dev *pdev,
                 case IDE:
                         WARN_ON((i & 1) || map[i + 1] != IDE);
                         pinfo[i / 2] = piix_port_info[ich5_pata];
+                        pinfo[i / 2].private_data = hpriv;
                         i++;
                         printk(" IDE IDE");
                         break;
@@ -905,7 +951,8 @@ static int piix_init_one (struct pci_dev *pdev, const struct pci_device_id *ent)
         if (host_flags & ATA_FLAG_SATA) {
                 piix_init_sata_map(pdev, port_info,
                                    piix_map_db_table[ent->driver_data]);
-                piix_init_pcs(pdev, piix_map_db_table[ent->driver_data]);
+                piix_init_pcs(pdev, port_info,
+                              piix_map_db_table[ent->driver_data]);
         }
 
         /* On ICH5, some BIOSen disable the interrupt using the