[PATCH] libata: make new reset act identical to ->phy_reset register-wise

This patch makes std component operations act identical to ->phy_reset
register-wise except for SError clearing on sata_std_hardreset.

Note that if a driver only implements/uses hardreset, it should not
use ata_std_probeinit() to avoid extra sata_phy_resume() and
ata_busy_sleep() compared to ->phy_reset.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>

1 files changed, 34 insertions, 17 deletions

diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index b938c7a37664..8424bd9ee26d 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -1924,11 +1924,20 @@ static int sata_phy_resume(struct ata_port *ap)
  *
  *      @ap is about to be probed.  Initialize it.  This function is
  *      to be used as standard callback for ata_drive_probe_reset().
+ *
+ *      NOTE!!! Do not use this function as probeinit if a low level
+ *      driver implements only hardreset.  Just pass NULL as probeinit
+ *      in that case.  Using this function is probably okay but doing
+ *      so makes reset sequence different from the original
+ *      ->phy_reset implementation and Jeff nervous.  :-P
  */
 extern void ata_std_probeinit(struct ata_port *ap)
 {
-        if (ap->flags & ATA_FLAG_SATA && ap->ops->scr_read)
+        if (ap->flags & ATA_FLAG_SATA && ap->ops->scr_read) {
                 sata_phy_resume(ap);
+                if (sata_dev_present(ap))
+                        ata_busy_sleep(ap, ATA_TMOUT_BOOT_QUICK, ATA_TMOUT_BOOT);
+        }
 }
 
 /**
@@ -1954,20 +1963,17 @@ int ata_std_softreset(struct ata_port *ap, int verbose, unsigned int *classes)
 
         DPRINTK("ENTER\n");
 
+        if (ap->ops->scr_read && !sata_dev_present(ap)) {
+                classes[0] = ATA_DEV_NONE;
+                goto out;
+        }
+
         /* determine if device 0/1 are present */
         if (ata_devchk(ap, 0))
                 devmask |= (1 << 0);
         if (slave_possible && ata_devchk(ap, 1))
                 devmask |= (1 << 1);
 
-        /* devchk reports device presence without actual device on
-         * most SATA controllers.  Check SStatus and turn devmask off
-         * if link is offline.  Note that we should continue resetting
-         * even when it seems like there's no device.
-         */
-        if (ap->ops->scr_read && !sata_dev_present(ap))
-                devmask = 0;
-
         /* select device 0 again */
         ap->ops->dev_select(ap, 0);
 
@@ -1989,6 +1995,7 @@ int ata_std_softreset(struct ata_port *ap, int verbose, unsigned int *classes)
         if (slave_possible && err != 0x81)
                 classes[1] = ata_dev_try_classify(ap, 1, &err);
 
+ out:
         DPRINTK("EXIT, classes[0]=%u [1]=%u\n", classes[0], classes[1]);
         return 0;
 }
@@ -2047,6 +2054,8 @@ int sata_std_hardreset(struct ata_port *ap, int verbose, unsigned int *class)
                 return -EIO;
         }
 
+        ap->ops->dev_select(ap, 0);     /* probably unnecessary */
+
         *class = ata_dev_try_classify(ap, 0, NULL);
 
         DPRINTK("EXIT, class=%u\n", *class);
@@ -2081,11 +2090,9 @@ void ata_std_postreset(struct ata_port *ap, unsigned int *classes)
         if (ap->cbl == ATA_CBL_SATA)
                 sata_print_link_status(ap);
 
-        /* bail out if no device is present */
-        if (classes[0] == ATA_DEV_NONE && classes[1] == ATA_DEV_NONE) {
-                DPRINTK("EXIT, no device\n");
-                return;
-        }
+        /* re-enable interrupts */
+        if (ap->ioaddr.ctl_addr)        /* FIXME: hack. create a hook instead */
+                ata_irq_on(ap);
 
         /* is double-select really necessary? */
         if (classes[0] != ATA_DEV_NONE)
@@ -2093,9 +2100,19 @@ void ata_std_postreset(struct ata_port *ap, unsigned int *classes)
         if (classes[1] != ATA_DEV_NONE)
                 ap->ops->dev_select(ap, 0);
 
-        /* re-enable interrupts & set up device control */
-        if (ap->ioaddr.ctl_addr)        /* FIXME: hack. create a hook instead */
-                ata_irq_on(ap);
+        /* bail out if no device is present */
+        if (classes[0] == ATA_DEV_NONE && classes[1] == ATA_DEV_NONE) {
+                DPRINTK("EXIT, no device\n");
+                return;
+        }
+
+        /* set up device control */
+        if (ap->ioaddr.ctl_addr) {
+                if (ap->flags & ATA_FLAG_MMIO)
+                        writeb(ap->ctl, (void __iomem *) ap->ioaddr.ctl_addr);
+                else
+                        outb(ap->ctl, ap->ioaddr.ctl_addr);
+        }
 
         DPRINTK("EXIT\n");
 }