sata_mv NCQ and SError fixes for mv_err_intr

Sigh.  Undo some earlier changes to mv_port_intr(),
so that we now read/clear SError again in all cases.

Arrange the top of the function to be as close as possible
to what we need for a later update (in this series) for ERR_DEV handling.

Fix things so that libata-eh can attempt a READ_LOG_EXT_10H
in response to a failed NCQ command, by just doing a local
mv_eh_freeze() rather than ata_port_freeze().

This will now fully handle NCQ errors much of the time,
but more fixes are needed for FBS/PMP, and for certain chip errata.

Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

1 files changed, 43 insertions, 21 deletions

diff --git a/drivers/ata/sata_mv.c b/drivers/ata/sata_mv.c
index e4d411cec79a..d995e0e15d87 100644
--- a/drivers/ata/sata_mv.c
+++ b/drivers/ata/sata_mv.c
@@ -1627,7 +1627,7 @@ static void mv_unexpected_intr(struct ata_port *ap)
  *      LOCKING:
  *      Inherited from caller.
  */
-static void mv_err_intr(struct ata_port *ap, struct ata_queued_cmd *qc)
+static void mv_err_intr(struct ata_port *ap)
 {
         void __iomem *port_mmio = mv_ap_base(ap);
         u32 edma_err_cause, eh_freeze_mask, serr = 0;
@@ -1635,24 +1635,33 @@ static void mv_err_intr(struct ata_port *ap, struct ata_queued_cmd *qc)
         struct mv_host_priv *hpriv = ap->host->private_data;
         unsigned int action = 0, err_mask = 0;
         struct ata_eh_info *ehi = &ap->link.eh_info;
-
-        ata_ehi_clear_desc(ehi);
+        struct ata_queued_cmd *qc;
+        int abort = 0;
 
         /*
-         * Read and clear the err_cause bits.  This won't actually
-         * clear for some errors (eg. SError), but we will be doing
-         * a hard reset in those cases regardless, which *will* clear it.
+         * Read and clear the SError and err_cause bits.
          */
+        sata_scr_read(&ap->link, SCR_ERROR, &serr);
+        sata_scr_write_flush(&ap->link, SCR_ERROR, serr);
+
         edma_err_cause = readl(port_mmio + EDMA_ERR_IRQ_CAUSE_OFS);
         writelfl(~edma_err_cause, port_mmio + EDMA_ERR_IRQ_CAUSE_OFS);
 
-        ata_ehi_push_desc(ehi, "edma_err_cause=%08x", edma_err_cause);
+        ata_port_printk(ap, KERN_INFO, "%s: err_cause=%08x pp_flags=0x%x\n",
+                        __func__, edma_err_cause, pp->pp_flags);
 
+        qc = mv_get_active_qc(ap);
+        ata_ehi_clear_desc(ehi);
+        ata_ehi_push_desc(ehi, "edma_err_cause=%08x pp_flags=%08x",
+                          edma_err_cause, pp->pp_flags);
         /*
          * All generations share these EDMA error cause bits:
          */
-        if (edma_err_cause & EDMA_ERR_DEV)
+        if (edma_err_cause & EDMA_ERR_DEV) {
                 err_mask |= AC_ERR_DEV;
+                action |= ATA_EH_RESET;
+                ata_ehi_push_desc(ehi, "dev error");
+        }
         if (edma_err_cause & (EDMA_ERR_D_PAR | EDMA_ERR_PRD_PAR |
                         EDMA_ERR_CRQB_PAR | EDMA_ERR_CRPB_PAR |
                         EDMA_ERR_INTRL_PAR)) {
@@ -1684,13 +1693,6 @@ static void mv_err_intr(struct ata_port *ap, struct ata_queued_cmd *qc)
                         ata_ehi_push_desc(ehi, "EDMA self-disable");
                 }
                 if (edma_err_cause & EDMA_ERR_SERR) {
-                        /*
-                         * Ensure that we read our own SCR, not a pmp link SCR:
-                         */
-                        ap->ops->scr_read(ap, SCR_ERROR, &serr);
-                        /*
-                         * Don't clear SError here; leave it for libata-eh:
-                         */
                         ata_ehi_push_desc(ehi, "SError=%08x", serr);
                         err_mask |= AC_ERR_ATA_BUS;
                         action |= ATA_EH_RESET;
@@ -1710,10 +1712,29 @@ static void mv_err_intr(struct ata_port *ap, struct ata_queued_cmd *qc)
         else
                 ehi->err_mask |= err_mask;
 
-        if (edma_err_cause & eh_freeze_mask)
+        if (err_mask == AC_ERR_DEV) {
+                /*
+                 * Cannot do ata_port_freeze() here,
+                 * because it would kill PIO access,
+                 * which is needed for further diagnosis.
+                 */
+                mv_eh_freeze(ap);
+                abort = 1;
+        } else if (edma_err_cause & eh_freeze_mask) {
+                /*
+                 * Note to self: ata_port_freeze() calls ata_port_abort()
+                 */
                 ata_port_freeze(ap);
-        else
-                ata_port_abort(ap);
+        } else {
+                abort = 1;
+        }
+
+        if (abort) {
+                if (qc)
+                        ata_link_abort(qc->dev->link);
+                else
+                        ata_port_abort(ap);
+        }
 }
 
 static void mv_process_crpb_response(struct ata_port *ap,
@@ -1740,8 +1761,9 @@ static void mv_process_crpb_response(struct ata_port *ap,
                         }
                 }
                 ata_status = edma_status >> CRPB_FLAG_STATUS_SHIFT;
-                qc->err_mask |= ac_err_mask(ata_status);
-                ata_qc_complete(qc);
+                if (!ac_err_mask(ata_status))
+                        ata_qc_complete(qc);
+                /* else: leave it for mv_err_intr() */
         } else {
                 ata_port_printk(ap, KERN_ERR, "%s: no qc for tag=%d\n",
                                 __func__, tag);
@@ -1845,7 +1867,7 @@ static int mv_host_intr(struct ata_host *host, u32 main_irq_cause)
                  * Handle chip-reported errors, or continue on to handle PIO.
                  */
                 if (unlikely(port_cause & ERR_IRQ)) {
-                        mv_err_intr(ap, mv_get_active_qc(ap));
+                        mv_err_intr(ap);
                 } else if (hc_irq_cause & (DEV_IRQ << hardport)) {
                         if (!(pp->pp_flags & MV_PP_FLAG_EDMA_EN)) {
                                 struct ata_queued_cmd *qc = mv_get_active_qc(ap);