8 files changed, 60 insertions, 37 deletions

diff --git a/drivers/ata/Kconfig b/drivers/ata/Kconfig
index 20e03a7eb8b4..c2706047337f 100644
--- a/drivers/ata/Kconfig
+++ b/drivers/ata/Kconfig
@@ -116,7 +116,7 @@ config AHCI_ST
 
 config AHCI_IMX
         tristate "Freescale i.MX AHCI SATA support"
-        depends on MFD_SYSCON
+        depends on MFD_SYSCON && (ARCH_MXC || COMPILE_TEST)
         help
           This option enables support for the Freescale i.MX SoC's
           onboard AHCI SATA.
@@ -134,8 +134,7 @@ config AHCI_SUNXI
 
 config AHCI_XGENE
         tristate "APM X-Gene 6.0Gbps AHCI SATA host controller support"
-        depends on ARM64 || COMPILE_TEST
-        select PHY_XGENE
+        depends on PHY_XGENE
         help
          This option enables support for APM X-Gene SoC SATA host controller.
 
diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index 5a0bf8ed649b..71e15b73513d 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -1164,9 +1164,9 @@ static inline void ahci_gtf_filter_workaround(struct ata_host *host)
 #endif
 
 static int ahci_init_interrupts(struct pci_dev *pdev, unsigned int n_ports,
-                         struct ahci_host_priv *hpriv)
+                                struct ahci_host_priv *hpriv)
 {
-        int nvec;
+        int rc, nvec;
 
         if (hpriv->flags & AHCI_HFLAG_NO_MSI)
                 goto intx;
@@ -1183,12 +1183,19 @@ static int ahci_init_interrupts(struct pci_dev *pdev, unsigned int n_ports,
         if (nvec < n_ports)
                 goto single_msi;
 
-        nvec = pci_enable_msi_range(pdev, nvec, nvec);
-        if (nvec == -ENOSPC)
+        rc = pci_enable_msi_exact(pdev, nvec);
+        if (rc == -ENOSPC)
                 goto single_msi;
-        else if (nvec < 0)
+        else if (rc < 0)
                 goto intx;
 
+        /* fallback to single MSI mode if the controller enforced MRSM mode */
+        if (readl(hpriv->mmio + HOST_CTL) & HOST_MRSM) {
+                pci_disable_msi(pdev);
+                printk(KERN_INFO "ahci: MRSM is on, fallback to single MSI\n");
+                goto single_msi;
+        }
+
         return nvec;
 
 single_msi:
@@ -1232,18 +1239,18 @@ int ahci_host_activate(struct ata_host *host, int irq, unsigned int n_msis)
                 return rc;
 
         for (i = 0; i < host->n_ports; i++) {
-                const char* desc;
                 struct ahci_port_priv *pp = host->ports[i]->private_data;
 
-                /* pp is NULL for dummy ports */
-                if (pp)
-                        desc = pp->irq_desc;
-                else
-                        desc = dev_driver_string(host->dev);
+                /* Do not receive interrupts sent by dummy ports */
+                if (!pp) {
+                        disable_irq(irq + i);
+                        continue;
+                }
 
-                rc = devm_request_threaded_irq(host->dev,
-                        irq + i, ahci_hw_interrupt, ahci_thread_fn, IRQF_SHARED,
-                        desc, host->ports[i]);
+                rc = devm_request_threaded_irq(host->dev, irq + i,
+                                               ahci_hw_interrupt,
+                                               ahci_thread_fn, IRQF_SHARED,
+                                               pp->irq_desc, host->ports[i]);
                 if (rc)
                         goto out_free_irqs;
         }
diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h
index 51af275b3388..b5eb886da226 100644
--- a/drivers/ata/ahci.h
+++ b/drivers/ata/ahci.h
@@ -94,6 +94,7 @@ enum {
         /* HOST_CTL bits */
         HOST_RESET              = (1 << 0),  /* reset controller; self-clear */
         HOST_IRQ_EN             = (1 << 1),  /* global IRQ enable */
+        HOST_MRSM               = (1 << 2),  /* MSI Revert to Single Message */
         HOST_AHCI_EN            = (1 << 31), /* AHCI enabled */
 
         /* HOST_CAP bits */
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index c19734d96d7e..943cc8b83e59 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -4224,8 +4224,10 @@ static const struct ata_blacklist_entry ata_device_blacklist [] = {
         { "PIONEER DVD-RW  DVR-216D",   NULL,   ATA_HORKAGE_NOSETXFER },
 
         /* devices that don't properly handle queued TRIM commands */
-        { "Micron_M500*",               NULL,   ATA_HORKAGE_NO_NCQ_TRIM, },
-        { "Crucial_CT???M500SSD*",      NULL,   ATA_HORKAGE_NO_NCQ_TRIM, },
+        { "Micron_M500*",               "MU0[1-4]*",    ATA_HORKAGE_NO_NCQ_TRIM, },
+        { "Crucial_CT???M500SSD*",      "MU0[1-4]*",    ATA_HORKAGE_NO_NCQ_TRIM, },
+        { "Micron_M550*",               NULL,           ATA_HORKAGE_NO_NCQ_TRIM, },
+        { "Crucial_CT???M550SSD*",      NULL,           ATA_HORKAGE_NO_NCQ_TRIM, },
 
         /*
          * Some WD SATA-I drives spin up and down erratically when the link
@@ -4792,21 +4794,26 @@ void swap_buf_le16(u16 *buf, unsigned int buf_words)
 static struct ata_queued_cmd *ata_qc_new(struct ata_port *ap)
 {
         struct ata_queued_cmd *qc = NULL;
-        unsigned int i;
+        unsigned int i, tag;
 
         /* no command while frozen */
         if (unlikely(ap->pflags & ATA_PFLAG_FROZEN))
                 return NULL;
 
-        /* the last tag is reserved for internal command. */
-        for (i = 0; i < ATA_MAX_QUEUE - 1; i++)
-                if (!test_and_set_bit(i, &ap->qc_allocated)) {
-                        qc = __ata_qc_from_tag(ap, i);
+        for (i = 0; i < ATA_MAX_QUEUE; i++) {
+                tag = (i + ap->last_tag + 1) % ATA_MAX_QUEUE;
+
+                /* the last tag is reserved for internal command. */
+                if (tag == ATA_TAG_INTERNAL)
+                        continue;
+
+                if (!test_and_set_bit(tag, &ap->qc_allocated)) {
+                        qc = __ata_qc_from_tag(ap, tag);
+                        qc->tag = tag;
+                        ap->last_tag = tag;
                         break;
                 }
-
-        if (qc)
-                qc->tag = i;
+        }
 
         return qc;
 }
diff --git a/drivers/ata/pata_arasan_cf.c b/drivers/ata/pata_arasan_cf.c
index 6fac524c2f50..4edb1a81f63f 100644
--- a/drivers/ata/pata_arasan_cf.c
+++ b/drivers/ata/pata_arasan_cf.c
@@ -898,9 +898,12 @@ static int arasan_cf_probe(struct platform_device *pdev)
 
         cf_card_detect(acdev, 0);
 
-        return ata_host_activate(host, acdev->irq, irq_handler, 0,
-                        &arasan_cf_sht);
+        ret = ata_host_activate(host, acdev->irq, irq_handler, 0,
+                                &arasan_cf_sht);
+        if (!ret)
+                return 0;
 
+        cf_exit(acdev);
 free_clk:
         clk_put(acdev->clk);
         return ret;
diff --git a/drivers/ata/pata_at91.c b/drivers/ata/pata_at91.c
index e9c87274a781..8a66f23af4c4 100644
--- a/drivers/ata/pata_at91.c
+++ b/drivers/ata/pata_at91.c
@@ -407,12 +407,13 @@ static int pata_at91_probe(struct platform_device *pdev)
 
         host->private_data = info;
 
-        return ata_host_activate(host, gpio_is_valid(irq) ? gpio_to_irq(irq) : 0,
-                        gpio_is_valid(irq) ? ata_sff_interrupt : NULL,
-                        irq_flags, &pata_at91_sht);
+        ret = ata_host_activate(host, gpio_is_valid(irq) ? gpio_to_irq(irq) : 0,
+                                gpio_is_valid(irq) ? ata_sff_interrupt : NULL,
+                                irq_flags, &pata_at91_sht);
+        if (ret)
+                goto err_put;
 
-        if (!ret)
-                return 0;
+        return 0;
 
 err_put:
         clk_put(info->mck);
diff --git a/drivers/ata/pata_samsung_cf.c b/drivers/ata/pata_samsung_cf.c
index a79566d05666..0610e78c8a2a 100644
--- a/drivers/ata/pata_samsung_cf.c
+++ b/drivers/ata/pata_samsung_cf.c
@@ -594,9 +594,13 @@ static int __init pata_s3c_probe(struct platform_device *pdev)
 
         platform_set_drvdata(pdev, host);
 
-        return ata_host_activate(host, info->irq,
-                        info->irq ? pata_s3c_irq : NULL,
-                        0, &pata_s3c_sht);
+        ret = ata_host_activate(host, info->irq,
+                                info->irq ? pata_s3c_irq : NULL,
+                                0, &pata_s3c_sht);
+        if (ret)
+                goto stop_clk;
+
+        return 0;
 
 stop_clk:
         clk_disable(info->clk);
diff --git a/include/linux/libata.h b/include/linux/libata.h
index 1de36be64df4..5ab4e3a76721 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -822,6 +822,7 @@ struct ata_port {
         unsigned long           qc_allocated;
         unsigned int            qc_active;
         int                     nr_active_links; /* #links with active qcs */
+        unsigned int            last_tag;       /* track next tag hw expects */
 
         struct ata_link         link;           /* host default link */
         struct ata_link         *slave_link;    /* see ata_slave_link_init() */