1 files changed, 121 insertions, 24 deletions

diff --git a/drivers/ata/libata-sff.c b/drivers/ata/libata-sff.c
index 3c2d2289f85e..c0908c225483 100644
--- a/drivers/ata/libata-sff.c
+++ b/drivers/ata/libata-sff.c
@@ -247,7 +247,7 @@ u8 ata_sff_check_status(struct ata_port *ap)
  *      LOCKING:
  *      Inherited from caller.
  */
-u8 ata_sff_altstatus(struct ata_port *ap)
+static u8 ata_sff_altstatus(struct ata_port *ap)
 {
         if (ap->ops->sff_check_altstatus)
                 return ap->ops->sff_check_altstatus(ap);
@@ -256,6 +256,93 @@ u8 ata_sff_altstatus(struct ata_port *ap)
 }
 
 /**
+ *      ata_sff_irq_status - Check if the device is busy
+ *      @ap: port where the device is
+ *
+ *      Determine if the port is currently busy. Uses altstatus
+ *      if available in order to avoid clearing shared IRQ status
+ *      when finding an IRQ source. Non ctl capable devices don't
+ *      share interrupt lines fortunately for us.
+ *
+ *      LOCKING:
+ *      Inherited from caller.
+ */
+static u8 ata_sff_irq_status(struct ata_port *ap)
+{
+        u8 status;
+
+        if (ap->ops->sff_check_altstatus || ap->ioaddr.altstatus_addr) {
+                status = ata_sff_altstatus(ap);
+                /* Not us: We are busy */
+                if (status & ATA_BUSY)
+                        return status;
+        }
+        /* Clear INTRQ latch */
+        status = ap->ops->sff_check_status(ap);
+        return status;
+}
+
+/**
+ *      ata_sff_sync - Flush writes
+ *      @ap: Port to wait for.
+ *
+ *      CAUTION:
+ *      If we have an mmio device with no ctl and no altstatus
+ *      method this will fail. No such devices are known to exist.
+ *
+ *      LOCKING:
+ *      Inherited from caller.
+ */
+
+static void ata_sff_sync(struct ata_port *ap)
+{
+        if (ap->ops->sff_check_altstatus)
+                ap->ops->sff_check_altstatus(ap);
+        else if (ap->ioaddr.altstatus_addr)
+                ioread8(ap->ioaddr.altstatus_addr);
+}
+
+/**
+ *      ata_sff_pause           -       Flush writes and wait 400nS
+ *      @ap: Port to pause for.
+ *
+ *      CAUTION:
+ *      If we have an mmio device with no ctl and no altstatus
+ *      method this will fail. No such devices are known to exist.
+ *
+ *      LOCKING:
+ *      Inherited from caller.
+ */
+
+void ata_sff_pause(struct ata_port *ap)
+{
+        ata_sff_sync(ap);
+        ndelay(400);
+}
+
+/**
+ *      ata_sff_dma_pause       -       Pause before commencing DMA
+ *      @ap: Port to pause for.
+ *
+ *      Perform I/O fencing and ensure sufficient cycle delays occur
+ *      for the HDMA1:0 transition
+ */
+ 
+void ata_sff_dma_pause(struct ata_port *ap)
+{
+        if (ap->ops->sff_check_altstatus || ap->ioaddr.altstatus_addr) {
+                /* An altstatus read will cause the needed delay without
+                   messing up the IRQ status */
+                ata_sff_altstatus(ap);
+                return;
+        }
+        /* There are no DMA controllers without ctl. BUG here to ensure
+           we never violate the HDMA1:0 transition timing and risk
+           corruption. */
+        BUG();
+}
+
+/**
  *      ata_sff_busy_sleep - sleep until BSY clears, or timeout
  *      @ap: port containing status register to be polled
  *      @tmout_pat: impatience timeout
@@ -742,7 +829,7 @@ static void ata_pio_sectors(struct ata_queued_cmd *qc)
         } else
                 ata_pio_sector(qc);
 
-        ata_sff_altstatus(qc->ap); /* flush */
+        ata_sff_sync(qc->ap); /* flush */
 }
 
 /**
@@ -763,8 +850,9 @@ static void atapi_send_cdb(struct ata_port *ap, struct ata_queued_cmd *qc)
         WARN_ON(qc->dev->cdb_len < 12);
 
         ap->ops->sff_data_xfer(qc->dev, qc->cdb, qc->dev->cdb_len, 1);
-        ata_sff_altstatus(ap); /* flush */
-
+        ata_sff_sync(ap);
+        /* FIXME: If the CDB is for DMA do we need to do the transition delay
+           or is bmdma_start guaranteed to do it ? */
         switch (qc->tf.protocol) {
         case ATAPI_PROT_PIO:
                 ap->hsm_task_state = HSM_ST;
@@ -905,7 +993,7 @@ static void atapi_pio_bytes(struct ata_queued_cmd *qc)
 
         if (unlikely(__atapi_pio_bytes(qc, bytes)))
                 goto err_out;
-        ata_sff_altstatus(ap); /* flush */
+        ata_sff_sync(ap); /* flush */
 
         return;
 
@@ -1006,6 +1094,7 @@ static void ata_hsm_qc_complete(struct ata_queued_cmd *qc, int in_wq)
 int ata_sff_hsm_move(struct ata_port *ap, struct ata_queued_cmd *qc,
                      u8 status, int in_wq)
 {
+        struct ata_eh_info *ehi = &ap->link.eh_info;
         unsigned long flags = 0;
         int poll_next;
 
@@ -1037,9 +1126,12 @@ fsm_start:
                         if (likely(status & (ATA_ERR | ATA_DF)))
                                 /* device stops HSM for abort/error */
                                 qc->err_mask |= AC_ERR_DEV;
-                        else
+                        else {
                                 /* HSM violation. Let EH handle this */
+                                ata_ehi_push_desc(ehi,
+                                        "ST_FIRST: !(DRQ|ERR|DF)");
                                 qc->err_mask |= AC_ERR_HSM;
+                        }
 
                         ap->hsm_task_state = HSM_ST_ERR;
                         goto fsm_start;
@@ -1058,9 +1150,9 @@ fsm_start:
                          * the CDB.
                          */
                         if (!(qc->dev->horkage & ATA_HORKAGE_STUCK_ERR)) {
-                                ata_port_printk(ap, KERN_WARNING,
-                                                "DRQ=1 with device error, "
-                                                "dev_stat 0x%X\n", status);
+                                ata_ehi_push_desc(ehi, "ST_FIRST: "
+                                        "DRQ=1 with device error, "
+                                        "dev_stat 0x%X", status);
                                 qc->err_mask |= AC_ERR_HSM;
                                 ap->hsm_task_state = HSM_ST_ERR;
                                 goto fsm_start;
@@ -1117,9 +1209,9 @@ fsm_start:
                          * let the EH abort the command or reset the device.
                          */
                         if (unlikely(status & (ATA_ERR | ATA_DF))) {
-                                ata_port_printk(ap, KERN_WARNING, "DRQ=1 with "
-                                                "device error, dev_stat 0x%X\n",
-                                                status);
+                                ata_ehi_push_desc(ehi, "ST-ATAPI: "
+                                        "DRQ=1 with device error, "
+                                        "dev_stat 0x%X", status);
                                 qc->err_mask |= AC_ERR_HSM;
                                 ap->hsm_task_state = HSM_ST_ERR;
                                 goto fsm_start;
@@ -1138,13 +1230,17 @@ fsm_start:
                                 if (likely(status & (ATA_ERR | ATA_DF)))
                                         /* device stops HSM for abort/error */
                                         qc->err_mask |= AC_ERR_DEV;
-                                else
+                                else {
                                         /* HSM violation. Let EH handle this.
                                          * Phantom devices also trigger this
                                          * condition.  Mark hint.
                                          */
+                                        ata_ehi_push_desc(ehi, "ST-ATA: "
+                                                "DRQ=1 with device error, "
+                                                "dev_stat 0x%X", status);
                                         qc->err_mask |= AC_ERR_HSM |
                                                         AC_ERR_NODEV_HINT;
+                                }
 
                                 ap->hsm_task_state = HSM_ST_ERR;
                                 goto fsm_start;
@@ -1169,8 +1265,12 @@ fsm_start:
                                         status = ata_wait_idle(ap);
                                 }
 
-                                if (status & (ATA_BUSY | ATA_DRQ))
+                                if (status & (ATA_BUSY | ATA_DRQ)) {
+                                        ata_ehi_push_desc(ehi, "ST-ATA: "
+                                                "BUSY|DRQ persists on ERR|DF, "
+                                                "dev_stat 0x%X", status);
                                         qc->err_mask |= AC_ERR_HSM;
+                                }
 
                                 /* ata_pio_sectors() might change the
                                  * state to HSM_ST_LAST. so, the state
@@ -1489,14 +1589,10 @@ inline unsigned int ata_sff_host_intr(struct ata_port *ap,
                 goto idle_irq;
         }
 
-        /* check altstatus */
-        status = ata_sff_altstatus(ap);
-        if (status & ATA_BUSY)
-                goto idle_irq;
 
-        /* check main status, clearing INTRQ */
-        status = ap->ops->sff_check_status(ap);
-        if (unlikely(status & ATA_BUSY))
+        /* check main status, clearing INTRQ if needed */
+        status = ata_sff_irq_status(ap);
+        if (status & ATA_BUSY)
                 goto idle_irq;
 
         /* ack bmdma irq events */
@@ -2030,7 +2126,7 @@ void ata_sff_error_handler(struct ata_port *ap)
                 ap->ops->bmdma_stop(qc);
         }
 
-        ata_sff_altstatus(ap);
+        ata_sff_sync(ap);               /* FIXME: We don't need this */
         ap->ops->sff_check_status(ap);
         ap->ops->sff_irq_clear(ap);
 
@@ -2203,7 +2299,7 @@ void ata_bmdma_stop(struct ata_queued_cmd *qc)
                  mmio + ATA_DMA_CMD);
 
         /* one-PIO-cycle guaranteed wait, per spec, for HDMA1:0 transition */
-        ata_sff_altstatus(ap);        /* dummy read */
+        ata_sff_dma_pause(ap);
 }
 
 /**
@@ -2722,7 +2818,8 @@ EXPORT_SYMBOL_GPL(ata_sff_qc_prep);
 EXPORT_SYMBOL_GPL(ata_sff_dumb_qc_prep);
 EXPORT_SYMBOL_GPL(ata_sff_dev_select);
 EXPORT_SYMBOL_GPL(ata_sff_check_status);
-EXPORT_SYMBOL_GPL(ata_sff_altstatus);
+EXPORT_SYMBOL_GPL(ata_sff_dma_pause);
+EXPORT_SYMBOL_GPL(ata_sff_pause);
 EXPORT_SYMBOL_GPL(ata_sff_busy_sleep);
 EXPORT_SYMBOL_GPL(ata_sff_wait_ready);
 EXPORT_SYMBOL_GPL(ata_sff_tf_load);