[PATCH] libata-hp-prep: implement ap->hw_sata_spd_limit

Add ap->hw_sata_spd_limit and initialize it once during the boot
initialization (or driver load initialization).  ap->sata_spd_limit is
reset to ap->hw_sata_spd_limit on hotplug.  This prevents spd limits
introduced by earlier devices from affecting new devices.

Signed-off-by: Tejun Heo <htejun@gmail.com>

1 files changed, 12 insertions, 9 deletions

diff --git a/drivers/scsi/libata-core.c b/drivers/scsi/libata-core.c
index a07ab77d32d6..b1a02fdbb0a5 100644
--- a/drivers/scsi/libata-core.c
+++ b/drivers/scsi/libata-core.c
@@ -2466,17 +2466,9 @@ static int sata_phy_resume(struct ata_port *ap)
  */
 void ata_std_probeinit(struct ata_port *ap)
 {
-        u32 scontrol;
-
         /* resume link */
         sata_phy_resume(ap);
 
-        /* init sata_spd_limit to the current value */
-        if (sata_scr_read(ap, SCR_CONTROL, &scontrol) == 0) {
-                int spd = (scontrol >> 4) & 0xf;
-                ap->sata_spd_limit &= (1 << spd) - 1;
-        }
-
         /* wait for device */
         if (ata_port_online(ap))
                 ata_busy_sleep(ap, ATA_TMOUT_BOOT_QUICK, ATA_TMOUT_BOOT);
@@ -5155,6 +5147,9 @@ void ata_dev_init(struct ata_device *dev)
         struct ata_port *ap = dev->ap;
         unsigned long flags;
 
+        /* SATA spd limit is bound to the first device */
+        ap->sata_spd_limit = ap->hw_sata_spd_limit;
+
         /* High bits of dev->flags are used to record warm plug
          * requests which occur asynchronously.  Synchronize using
          * host_set lock.
@@ -5210,7 +5205,7 @@ static void ata_host_init(struct ata_port *ap, struct Scsi_Host *host,
         ap->udma_mask = ent->udma_mask;
         ap->flags |= ent->host_flags;
         ap->ops = ent->port_ops;
-        ap->sata_spd_limit = UINT_MAX;
+        ap->hw_sata_spd_limit = UINT_MAX;
         ap->active_tag = ATA_TAG_POISON;
         ap->last_ctl = 0xFF;
         ap->msg_enable = ATA_MSG_DRV;
@@ -5375,10 +5370,18 @@ int ata_device_add(const struct ata_probe_ent *ent)
         DPRINTK("probe begin\n");
         for (i = 0; i < count; i++) {
                 struct ata_port *ap;
+                u32 scontrol;
                 int rc;
 
                 ap = host_set->ports[i];
 
+                /* init sata_spd_limit to the current value */
+                if (sata_scr_read(ap, SCR_CONTROL, &scontrol) == 0) {
+                        int spd = (scontrol >> 4) & 0xf;
+                        ap->hw_sata_spd_limit &= (1 << spd) - 1;
+                }
+                ap->sata_spd_limit = ap->hw_sata_spd_limit;
+
                 DPRINTK("ata%u: bus probe begin\n", ap->id);
                 rc = ata_bus_probe(ap);
                 DPRINTK("ata%u: bus probe end\n", ap->id);