Now that libata is smart enought to handle both soft and hard resets,
add softreset method.
Signed-off-by: Tejun Heo <[email protected]>
---
There has been no relevant change for AHCI since last post. The
following patch is identical to the last posting.
ahci.c | 135 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 134 insertions(+), 1 deletion(-)
--- a/drivers/scsi/ahci.c
+++ b/drivers/scsi/ahci.c
@@ -513,6 +513,138 @@ static void ahci_fill_cmd_slot(struct ah
pp->cmd_slot[0].tbl_addr_hi = cpu_to_le32((pp->cmd_tbl_dma >> 16) >> 16);
}
+static int ahci_poll_register(void __iomem *reg, u32 mask, u32 val,
+ unsigned long interval_msec,
+ unsigned long timeout_msec)
+{
+ unsigned long timeout;
+ u32 tmp;
+
+ timeout = jiffies + (timeout_msec * HZ) / 1000;
+ do {
+ tmp = readl(reg);
+ if ((tmp & mask) == val)
+ return 0;
+ msleep(interval_msec);
+ } while (time_before(jiffies, timeout));
+
+ return -1;
+}
+
+static int ahci_softreset(struct ata_port *ap, int verbose, unsigned int *class)
+{
+ struct ahci_host_priv *hpriv = ap->host_set->private_data;
+ struct ahci_port_priv *pp = ap->private_data;
+ void __iomem *mmio = ap->host_set->mmio_base;
+ void __iomem *port_mmio = ahci_port_base(mmio, ap->port_no);
+ const u32 cmd_fis_len = 5; /* five dwords */
+ const char *reason = NULL;
+ struct ata_taskfile tf;
+ u8 *fis;
+ int rc;
+
+ DPRINTK("ENTER\n");
+
+ /* prepare for SRST (AHCI-1.1 10.4.1) */
+ rc = ahci_stop_engine(ap);
+ if (rc) {
+ reason = "failed to stop engine";
+ goto fail_restart;
+ }
+
+ /* check BUSY/DRQ, perform Command List Override if necessary */
+ ahci_tf_read(ap, &tf);
+ if (tf.command & (ATA_BUSY | ATA_DRQ)) {
+ u32 tmp;
+
+ if (!(hpriv->cap & HOST_CAP_CLO)) {
+ rc = -EIO;
+ reason = "port busy but no CLO";
+ goto fail_restart;
+ }
+
+ tmp = readl(port_mmio + PORT_CMD);
+ tmp |= PORT_CMD_CLO;
+ writel(tmp, port_mmio + PORT_CMD);
+ readl(port_mmio + PORT_CMD); /* flush */
+
+ if (ahci_poll_register(port_mmio + PORT_CMD, PORT_CMD_CLO, 0x0,
+ 1, 500)) {
+ rc = -EIO;
+ reason = "CLO failed";
+ goto fail_restart;
+ }
+ }
+
+ /* restart engine */
+ ahci_start_engine(ap);
+
+ ata_tf_init(ap, &tf, 0);
+ fis = pp->cmd_tbl;
+
+ /* issue the first D2H Register FIS */
+ ahci_fill_cmd_slot(pp, cmd_fis_len | AHCI_CMD_RESET | AHCI_CMD_CLR_BUSY);
+
+ tf.ctl |= ATA_SRST;
+ ata_tf_to_fis(&tf, fis, 0);
+ fis[1] &= ~(1 << 7); /* turn off Command FIS bit */
+
+ writel(1, port_mmio + PORT_CMD_ISSUE);
+ readl(port_mmio + PORT_CMD_ISSUE); /* flush */
+
+ if (ahci_poll_register(port_mmio + PORT_CMD_ISSUE, 0x1, 0x0, 1, 500)) {
+ rc = -EIO;
+ reason = "1st FIS failed";
+ goto fail;
+ }
+
+ /* spec says at least 5us, but be generous and sleep for 1ms */
+ msleep(1);
+
+ /* issue the second D2H Register FIS */
+ ahci_fill_cmd_slot(pp, cmd_fis_len);
+
+ tf.ctl &= ~ATA_SRST;
+ ata_tf_to_fis(&tf, fis, 0);
+ fis[1] &= ~(1 << 7); /* turn off Command FIS bit */
+
+ writel(1, port_mmio + PORT_CMD_ISSUE);
+ readl(port_mmio + PORT_CMD_ISSUE); /* flush */
+
+ /* spec mandates ">= 2ms" before checking status.
+ * We wait 150ms, because that was the magic delay used for
+ * ATAPI devices in Hale Landis's ATADRVR, for the period of time
+ * between when the ATA command register is written, and then
+ * status is checked. Because waiting for "a while" before
+ * checking status is fine, post SRST, we perform this magic
+ * delay here as well.
+ */
+ msleep(150);
+
+ *class = ATA_DEV_NONE;
+ if (sata_dev_present(ap)) {
+ if (ata_busy_sleep(ap, ATA_TMOUT_BOOT_QUICK, ATA_TMOUT_BOOT)) {
+ rc = -EIO;
+ reason = "device not ready";
+ goto fail;
+ }
+ *class = ahci_dev_classify(ap);
+ }
+
+ DPRINTK("EXIT, class=%u\n", *class);
+ return 0;
+
+ fail_restart:
+ ahci_start_engine(ap);
+ fail:
+ if (verbose)
+ printk(KERN_ERR "ata%u: softreset failed (%s)\n",
+ ap->id, reason);
+ else
+ DPRINTK("EXIT, rc=%d reason=\"%s\"\n", rc, reason);
+ return rc;
+}
+
static int ahci_hardreset(struct ata_port *ap, int verbose, unsigned int *class)
{
int rc;
@@ -553,7 +685,8 @@ static void ahci_postreset(struct ata_po
static int ahci_probe_reset(struct ata_port *ap, unsigned int *classes)
{
- return ata_drive_probe_reset(ap, NULL, NULL, ahci_hardreset,
+ return ata_drive_probe_reset(ap, ata_std_probeinit,
+ ahci_softreset, ahci_hardreset,
ahci_postreset, classes);
}
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
