ahci: separate out ahci_exec_polled_cmd()

Separate out ahci_exec_polled_cmd() from ahci_softreset().  This will
be used to implement ahci_pmp_read/write().  ahci_exec_polled_cmd()
performs reset_engine before returning if the command fails (times
out).  This is to improve robustness.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 33 insertions, 21 deletions

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index 1be238def0ed..db65f4a16021 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -993,17 +993,42 @@ static int ahci_kick_engine(struct ata_port *ap, int force_restart)
         return rc;
 }
 
-static int ahci_softreset(struct ata_port *ap, unsigned int *class,
-                          unsigned long deadline)
+static int ahci_exec_polled_cmd(struct ata_port *ap, int pmp,
+                                struct ata_taskfile *tf, int is_cmd, u16 flags,
+                                unsigned long timeout_msec)
 {
+        const u32 cmd_fis_len = 5; /* five dwords */
         struct ahci_port_priv *pp = ap->private_data;
         void __iomem *port_mmio = ahci_port_base(ap);
-        const u32 cmd_fis_len = 5; /* five dwords */
+        u8 *fis = pp->cmd_tbl;
+        u32 tmp;
+
+        /* prep the command */
+        ata_tf_to_fis(tf, pmp, is_cmd, fis);
+        ahci_fill_cmd_slot(pp, 0, cmd_fis_len | flags | (pmp << 12));
+
+        /* issue & wait */
+        writel(1, port_mmio + PORT_CMD_ISSUE);
+
+        if (timeout_msec) {
+                tmp = ata_wait_register(port_mmio + PORT_CMD_ISSUE, 0x1, 0x1,
+                                        1, timeout_msec);
+                if (tmp & 0x1) {
+                        ahci_kick_engine(ap, 1);
+                        return -EBUSY;
+                }
+        } else
+                readl(port_mmio + PORT_CMD_ISSUE);      /* flush */
+
+        return 0;
+}
+
+static int ahci_softreset(struct ata_port *ap, unsigned int *class,
+                          unsigned long deadline)
+{
         const char *reason = NULL;
         unsigned long now, msecs;
         struct ata_taskfile tf;
-        u32 tmp;
-        u8 *fis;
         int rc;
 
         DPRINTK("ENTER\n");
@@ -1021,7 +1046,6 @@ static int ahci_softreset(struct ata_port *ap, unsigned int *class,
                                 "failed to reset engine (errno=%d)", rc);
 
         ata_tf_init(ap->device, &tf);
-        fis = pp->cmd_tbl;
 
         /* issue the first D2H Register FIS */
         msecs = 0;
@@ -1029,16 +1053,9 @@ static int ahci_softreset(struct ata_port *ap, unsigned int *class,
         if (time_after(now, deadline))
                 msecs = jiffies_to_msecs(deadline - now);
 
-        ahci_fill_cmd_slot(pp, 0,
-                           cmd_fis_len | AHCI_CMD_RESET | AHCI_CMD_CLR_BUSY);
-
         tf.ctl |= ATA_SRST;
-        ata_tf_to_fis(&tf, 0, 0, fis);
-
-        writel(1, port_mmio + PORT_CMD_ISSUE);
-
-        tmp = ata_wait_register(port_mmio + PORT_CMD_ISSUE, 0x1, 0x1, 1, msecs);
-        if (tmp & 0x1) {
+        if (ahci_exec_polled_cmd(ap, 0, &tf, 0,
+                                 AHCI_CMD_RESET | AHCI_CMD_CLR_BUSY, msecs)) {
                 rc = -EIO;
                 reason = "1st FIS failed";
                 goto fail;
@@ -1048,13 +1065,8 @@ static int ahci_softreset(struct ata_port *ap, unsigned int *class,
         msleep(1);
 
         /* issue the second D2H Register FIS */
-        ahci_fill_cmd_slot(pp, 0, cmd_fis_len);
-
         tf.ctl &= ~ATA_SRST;
-        ata_tf_to_fis(&tf, 0, 0, fis);
-
-        writel(1, port_mmio + PORT_CMD_ISSUE);
-        readl(port_mmio + PORT_CMD_ISSUE);      /* flush */
+        ahci_exec_polled_cmd(ap, 0, &tf, 0, 0, 0);
 
         /* spec mandates ">= 2ms" before checking status.
          * We wait 150ms, because that was the magic delay used for