[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>

diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index b938c7a..8424bd9 100644 (file)
--- 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");
 }