[libata] add DMA setup FIS auto-activate feature

Hopefully results in fewer on-the-wire FIS's and no breakage.  We'll see!

Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

1 files changed, 29 insertions, 7 deletions

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 072ba5ea138f..98af50f16e0c 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -2299,29 +2299,49 @@ static inline u8 ata_dev_knobble(struct ata_device *dev)
         return ((ap->cbl == ATA_CBL_SATA) && (!ata_id_is_sata(dev->id)));
 }
 
-static void ata_dev_config_ncq(struct ata_device *dev,
+static int ata_dev_config_ncq(struct ata_device *dev,
                                char *desc, size_t desc_sz)
 {
         struct ata_port *ap = dev->link->ap;
         int hdepth = 0, ddepth = ata_id_queue_depth(dev->id);
+        unsigned int err_mask;
+        char *aa_desc = "";
 
         if (!ata_id_has_ncq(dev->id)) {
                 desc[0] = '\0';
-                return;
+                return 0;
         }
         if (dev->horkage & ATA_HORKAGE_NONCQ) {
                 snprintf(desc, desc_sz, "NCQ (not used)");
-                return;
+                return 0;
         }
         if (ap->flags & ATA_FLAG_NCQ) {
                 hdepth = min(ap->scsi_host->can_queue, ATA_MAX_QUEUE - 1);
                 dev->flags |= ATA_DFLAG_NCQ;
         }
 
+        if (!(dev->horkage & ATA_HORKAGE_BROKEN_FPDMA_AA) &&
+                (ap->flags & ATA_FLAG_FPDMA_AA) &&
+                ata_id_has_fpdma_aa(dev->id)) {
+                err_mask = ata_dev_set_feature(dev, SETFEATURES_SATA_ENABLE,
+                        SATA_FPDMA_AA);
+                if (err_mask) {
+                        ata_dev_printk(dev, KERN_ERR, "failed to enable AA"
+                                "(error_mask=0x%x)\n", err_mask);
+                        if (err_mask != AC_ERR_DEV) {
+                                dev->horkage |= ATA_HORKAGE_BROKEN_FPDMA_AA;
+                                return -EIO;
+                        }
+                } else
+                        aa_desc = ", AA";
+        }
+
         if (hdepth >= ddepth)
-                snprintf(desc, desc_sz, "NCQ (depth %d)", ddepth);
+                snprintf(desc, desc_sz, "NCQ (depth %d)%s", ddepth, aa_desc);
         else
-                snprintf(desc, desc_sz, "NCQ (depth %d/%d)", hdepth, ddepth);
+                snprintf(desc, desc_sz, "NCQ (depth %d/%d)%s", hdepth,
+                        ddepth, aa_desc);
+        return 0;
 }
 
 /**
@@ -2461,7 +2481,7 @@ int ata_dev_configure(struct ata_device *dev)
 
                 if (ata_id_has_lba(id)) {
                         const char *lba_desc;
-                        char ncq_desc[20];
+                        char ncq_desc[24];
 
                         lba_desc = "LBA";
                         dev->flags |= ATA_DFLAG_LBA;
@@ -2475,7 +2495,9 @@ int ata_dev_configure(struct ata_device *dev)
                         }
 
                         /* config NCQ */
-                        ata_dev_config_ncq(dev, ncq_desc, sizeof(ncq_desc));
+                        rc = ata_dev_config_ncq(dev, ncq_desc, sizeof(ncq_desc));
+                        if (rc)
+                                return rc;
 
                         /* print device info to dmesg */
                         if (ata_msg_drv(ap) && print_info) {