[PATCH 8/8] sata_sil24: reimplement hardreset

[Tejun Heo <htejun@gmail.com>]

Reimplement hardreset according to the datasheet.  The old hardreset
didn't reset controller status and the controller might not be ready
after reset.  Also, as SStatus is a bit slow to reflect PHY status
after reset, sata_std_hardrset() doesn't wait long enough before
proceeding.

Note that as we're not depending on SStatus, we can't depend on DET==1
condition to wait for link, so use shorter timeout for no device case.

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

---

 drivers/scsi/sata_sil24.c |   38 +++++++++++++++++++++++++++++++++++---
 1 files changed, 35 insertions(+), 3 deletions(-)

6d59c820f497b5af4db2532dcafab195759b7d28
diff --git a/drivers/scsi/sata_sil24.c b/drivers/scsi/sata_sil24.c
index 3d8047e..b468cca 100644
--- a/drivers/scsi/sata_sil24.c
+++ b/drivers/scsi/sata_sil24.c
@@ -518,10 +518,42 @@ static int sil24_softreset(struct ata_po
 
 static int sil24_hardreset(struct ata_port *ap, unsigned int *class)
 {
-	unsigned int dummy_class;
+	void __iomem *port = (void __iomem *)ap->ioaddr.cmd_addr;
+	const char *reason;
+	int tout_msec, rc;
+
+	/* sil24 does the right thing (tm) without any protection */
+	ata_set_sata_spd(ap);
+
+	tout_msec = 100;
+	if (sata_dev_present(ap))
+		tout_msec = 5000;
+
+	writel(PORT_CS_DEV_RST, port + PORT_CTRL_STAT);
+	rc = sil24_poll_register(port + PORT_CTRL_STAT,
+				 PORT_CS_DEV_RST, 0, 10, tout_msec);
+
+	if (rc) {
+		if (!sata_dev_present(ap))
+			return 0;
+		reason = "link not ready";
+		goto err;
+	}
+
+	if (ata_busy_sleep(ap, ATA_TMOUT_BOOT_QUICK, ATA_TMOUT_BOOT)) {
+		reason = "device not ready";
+		goto err;
+	}
+
+	/* SStatus is a bit sluggish (reports 0) on sil24, wait for it */
+	sil24_poll_register(port + PORT_SSTATUS, 0xf, 0x0, 10, 100);
+
+	/* no classification, just return */
+	return 0;
 
-	/* sil24 doesn't report device signature after hard reset */
-	return sata_std_hardreset(ap, &dummy_class);
+ err:
+	printk(KERN_ERR "ata%u: hardreset failed (%s)\n", ap->id, reason);
+	return -EIO;
 }
 
 static int sil24_probe_reset(struct ata_port *ap, unsigned int *classes)
-- 
1.2.4