1 files changed, 51 insertions, 9 deletions

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index e3c7b312287a..28a82e3403f1 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -75,6 +75,7 @@ enum {
         AHCI_CMD_CLR_BUSY       = (1 << 10),
 
         RX_FIS_D2H_REG          = 0x40, /* offset of D2H Register FIS data */
+        RX_FIS_SDB              = 0x58, /* offset of SDB FIS data */
         RX_FIS_UNK              = 0x60, /* offset of Unknown FIS data */
 
         board_ahci              = 0,
@@ -202,6 +203,10 @@ struct ahci_port_priv {
         dma_addr_t              cmd_tbl_dma;
         void                    *rx_fis;
         dma_addr_t              rx_fis_dma;
+        /* for NCQ spurious interrupt analysis */
+        int                     ncq_saw_spurious_sdb_cnt;
+        unsigned int            ncq_saw_d2h:1;
+        unsigned int            ncq_saw_dmas:1;
 };
 
 static u32 ahci_scr_read (struct ata_port *ap, unsigned int sc_reg);
@@ -898,7 +903,7 @@ static int ahci_hardreset(struct ata_port *ap, unsigned int *class)
 
         /* clear D2H reception area to properly wait for D2H FIS */
         ata_tf_init(ap->device, &tf);
-        tf.command = 0xff;
+        tf.command = 0x80;
         ata_tf_to_fis(&tf, d2h_fis, 0);
 
         rc = sata_std_hardreset(ap, class);
@@ -1109,8 +1114,9 @@ static void ahci_host_intr(struct ata_port *ap)
         void __iomem *mmio = ap->host->mmio_base;
         void __iomem *port_mmio = ahci_port_base(mmio, ap->port_no);
         struct ata_eh_info *ehi = &ap->eh_info;
+        struct ahci_port_priv *pp = ap->private_data;
         u32 status, qc_active;
-        int rc;
+        int rc, known_irq = 0;
 
         status = readl(port_mmio + PORT_IRQ_STAT);
         writel(status, port_mmio + PORT_IRQ_STAT);
@@ -1137,17 +1143,53 @@ static void ahci_host_intr(struct ata_port *ap)
 
         /* hmmm... a spurious interupt */
 
-        /* some devices send D2H reg with I bit set during NCQ command phase */
-        if (ap->sactive && (status & PORT_IRQ_D2H_REG_FIS))
+        /* if !NCQ, ignore.  No modern ATA device has broken HSM
+         * implementation for non-NCQ commands.
+         */
+        if (!ap->sactive)
                 return;
 
-        /* ignore interim PIO setup fis interrupts */
-        if (ata_tag_valid(ap->active_tag) && (status & PORT_IRQ_PIOS_FIS))
-                return;
+        if (status & PORT_IRQ_D2H_REG_FIS) {
+                if (!pp->ncq_saw_d2h)
+                        ata_port_printk(ap, KERN_INFO,
+                                "D2H reg with I during NCQ, "
+                                "this message won't be printed again\n");
+                pp->ncq_saw_d2h = 1;
+                known_irq = 1;
+        }
+
+        if (status & PORT_IRQ_DMAS_FIS) {
+                if (!pp->ncq_saw_dmas)
+                        ata_port_printk(ap, KERN_INFO,
+                                "DMAS FIS during NCQ, "
+                                "this message won't be printed again\n");
+                pp->ncq_saw_dmas = 1;
+                known_irq = 1;
+        }
+
+        if (status & PORT_IRQ_SDB_FIS &&
+                   pp->ncq_saw_spurious_sdb_cnt < 10) {
+                /* SDB FIS containing spurious completions might be
+                 * dangerous, we need to know more about them.  Print
+                 * more of it.
+                 */
+                const u32 *f = pp->rx_fis + RX_FIS_SDB;
+
+                ata_port_printk(ap, KERN_INFO, "Spurious SDB FIS during NCQ "
+                                "issue=0x%x SAct=0x%x FIS=%08x:%08x%s\n",
+                                readl(port_mmio + PORT_CMD_ISSUE),
+                                readl(port_mmio + PORT_SCR_ACT),
+                                le32_to_cpu(f[0]), le32_to_cpu(f[1]),
+                                pp->ncq_saw_spurious_sdb_cnt < 10 ?
+                                "" : ", shutting up");
+
+                pp->ncq_saw_spurious_sdb_cnt++;
+                known_irq = 1;
+        }
 
-        if (ata_ratelimit())
+        if (!known_irq)
                 ata_port_printk(ap, KERN_INFO, "spurious interrupt "
-                                "(irq_stat 0x%x active_tag %d sactive 0x%x)\n",
+                                "(irq_stat 0x%x active_tag 0x%x sactive 0x%x)\n",
                                 status, ap->active_tag, ap->sactive);
 }