1 files changed, 103 insertions, 18 deletions

diff --git a/drivers/ntb/ntb_hw.c b/drivers/ntb/ntb_hw.c
index 1cb6e51e6bda..170e8e60cdb7 100644
--- a/drivers/ntb/ntb_hw.c
+++ b/drivers/ntb/ntb_hw.c
@@ -141,6 +141,24 @@ void ntb_unregister_event_callback(struct ntb_device *ndev)
         ndev->event_cb = NULL;
 }
 
+static void ntb_irq_work(unsigned long data)
+{
+        struct ntb_db_cb *db_cb = (struct ntb_db_cb *)data;
+        int rc;
+
+        rc = db_cb->callback(db_cb->data, db_cb->db_num);
+        if (rc)
+                tasklet_schedule(&db_cb->irq_work);
+        else {
+                struct ntb_device *ndev = db_cb->ndev;
+                unsigned long mask;
+
+                mask = readw(ndev->reg_ofs.ldb_mask);
+                clear_bit(db_cb->db_num * ndev->bits_per_vector, &mask);
+                writew(mask, ndev->reg_ofs.ldb_mask);
+        }
+}
+
 /**
  * ntb_register_db_callback() - register a callback for doorbell interrupt
  * @ndev: pointer to ntb_device instance
@@ -155,7 +173,7 @@ void ntb_unregister_event_callback(struct ntb_device *ndev)
  * RETURNS: An appropriate -ERRNO error value on error, or zero for success.
  */
 int ntb_register_db_callback(struct ntb_device *ndev, unsigned int idx,
-                             void *data, void (*func)(void *data, int db_num))
+                             void *data, int (*func)(void *data, int db_num))
 {
         unsigned long mask;
 
@@ -166,6 +184,10 @@ int ntb_register_db_callback(struct ntb_device *ndev, unsigned int idx,
 
         ndev->db_cb[idx].callback = func;
         ndev->db_cb[idx].data = data;
+        ndev->db_cb[idx].ndev = ndev;
+
+        tasklet_init(&ndev->db_cb[idx].irq_work, ntb_irq_work,
+                     (unsigned long) &ndev->db_cb[idx]);
 
         /* unmask interrupt */
         mask = readw(ndev->reg_ofs.ldb_mask);
@@ -194,6 +216,8 @@ void ntb_unregister_db_callback(struct ntb_device *ndev, unsigned int idx)
         set_bit(idx * ndev->bits_per_vector, &mask);
         writew(mask, ndev->reg_ofs.ldb_mask);
 
+        tasklet_disable(&ndev->db_cb[idx].irq_work);
+
         ndev->db_cb[idx].callback = NULL;
 }
 
@@ -678,6 +702,7 @@ static int ntb_xeon_setup(struct ntb_device *ndev)
                                 return -EINVAL;
 
                         ndev->limits.max_mw = SNB_ERRATA_MAX_MW;
+                        ndev->limits.max_db_bits = SNB_MAX_DB_BITS;
                         ndev->reg_ofs.spad_write = ndev->mw[1].vbase +
                                                    SNB_SPAD_OFFSET;
                         ndev->reg_ofs.rdb = ndev->mw[1].vbase +
@@ -688,8 +713,21 @@ static int ntb_xeon_setup(struct ntb_device *ndev)
                          */
                         writeq(ndev->mw[1].bar_sz + 0x1000, ndev->reg_base +
                                SNB_PBAR4LMT_OFFSET);
+                        /* HW errata on the Limit registers.  They can only be
+                         * written when the base register is 4GB aligned and
+                         * < 32bit.  This should already be the case based on the
+                         * driver defaults, but write the Limit registers first
+                         * just in case.
+                         */
                 } else {
                         ndev->limits.max_mw = SNB_MAX_MW;
+
+                        /* HW Errata on bit 14 of b2bdoorbell register.  Writes
+                         * will not be mirrored to the remote system.  Shrink
+                         * the number of bits by one, since bit 14 is the last
+                         * bit.
+                         */
+                        ndev->limits.max_db_bits = SNB_MAX_DB_BITS - 1;
                         ndev->reg_ofs.spad_write = ndev->reg_base +
                                                    SNB_B2B_SPAD_OFFSET;
                         ndev->reg_ofs.rdb = ndev->reg_base +
@@ -699,6 +737,12 @@ static int ntb_xeon_setup(struct ntb_device *ndev)
                          * something silly
                          */
                         writeq(0, ndev->reg_base + SNB_PBAR4LMT_OFFSET);
+                        /* HW errata on the Limit registers.  They can only be
+                         * written when the base register is 4GB aligned and
+                         * < 32bit.  This should already be the case based on the
+                         * driver defaults, but write the Limit registers first
+                         * just in case.
+                         */
                 }
 
                 /* The Xeon errata workaround requires setting SBAR Base
@@ -769,6 +813,7 @@ static int ntb_xeon_setup(struct ntb_device *ndev)
                  * have an equal amount.
                  */
                 ndev->limits.max_spads = SNB_MAX_COMPAT_SPADS / 2;
+                ndev->limits.max_db_bits = SNB_MAX_DB_BITS;
                 /* Note: The SDOORBELL is the cause of the errata.  You REALLY
                  * don't want to touch it.
                  */
@@ -793,6 +838,7 @@ static int ntb_xeon_setup(struct ntb_device *ndev)
                  * have an equal amount.
                  */
                 ndev->limits.max_spads = SNB_MAX_COMPAT_SPADS / 2;
+                ndev->limits.max_db_bits = SNB_MAX_DB_BITS;
                 ndev->reg_ofs.rdb = ndev->reg_base + SNB_PDOORBELL_OFFSET;
                 ndev->reg_ofs.ldb = ndev->reg_base + SNB_SDOORBELL_OFFSET;
                 ndev->reg_ofs.ldb_mask = ndev->reg_base + SNB_SDBMSK_OFFSET;
@@ -819,7 +865,6 @@ static int ntb_xeon_setup(struct ntb_device *ndev)
         ndev->reg_ofs.lnk_stat = ndev->reg_base + SNB_SLINK_STATUS_OFFSET;
         ndev->reg_ofs.spci_cmd = ndev->reg_base + SNB_PCICMD_OFFSET;
 
-        ndev->limits.max_db_bits = SNB_MAX_DB_BITS;
         ndev->limits.msix_cnt = SNB_MSIX_CNT;
         ndev->bits_per_vector = SNB_DB_BITS_PER_VEC;
 
@@ -934,12 +979,16 @@ static irqreturn_t bwd_callback_msix_irq(int irq, void *data)
 {
         struct ntb_db_cb *db_cb = data;
         struct ntb_device *ndev = db_cb->ndev;
+        unsigned long mask;
 
         dev_dbg(&ndev->pdev->dev, "MSI-X irq %d received for DB %d\n", irq,
                 db_cb->db_num);
 
-        if (db_cb->callback)
-                db_cb->callback(db_cb->data, db_cb->db_num);
+        mask = readw(ndev->reg_ofs.ldb_mask);
+        set_bit(db_cb->db_num * ndev->bits_per_vector, &mask);
+        writew(mask, ndev->reg_ofs.ldb_mask);
+
+        tasklet_schedule(&db_cb->irq_work);
 
         /* No need to check for the specific HB irq, any interrupt means
          * we're connected.
@@ -955,12 +1004,16 @@ static irqreturn_t xeon_callback_msix_irq(int irq, void *data)
 {
         struct ntb_db_cb *db_cb = data;
         struct ntb_device *ndev = db_cb->ndev;
+        unsigned long mask;
 
         dev_dbg(&ndev->pdev->dev, "MSI-X irq %d received for DB %d\n", irq,
                 db_cb->db_num);
 
-        if (db_cb->callback)
-                db_cb->callback(db_cb->data, db_cb->db_num);
+        mask = readw(ndev->reg_ofs.ldb_mask);
+        set_bit(db_cb->db_num * ndev->bits_per_vector, &mask);
+        writew(mask, ndev->reg_ofs.ldb_mask);
+
+        tasklet_schedule(&db_cb->irq_work);
 
         /* On Sandybridge, there are 16 bits in the interrupt register
          * but only 4 vectors.  So, 5 bits are assigned to the first 3
@@ -986,7 +1039,7 @@ static irqreturn_t xeon_event_msix_irq(int irq, void *dev)
                 dev_err(&ndev->pdev->dev, "Error determining link status\n");
 
         /* bit 15 is always the link bit */
-        writew(1 << ndev->limits.max_db_bits, ndev->reg_ofs.ldb);
+        writew(1 << SNB_LINK_DB, ndev->reg_ofs.ldb);
 
         return IRQ_HANDLED;
 }
@@ -1075,6 +1128,10 @@ static int ntb_setup_msix(struct ntb_device *ndev)
                          "Only %d MSI-X vectors.  Limiting the number of queues to that number.\n",
                          rc);
                 msix_entries = rc;
+
+                rc = pci_enable_msix(pdev, ndev->msix_entries, msix_entries);
+                if (rc)
+                        goto err1;
         }
 
         for (i = 0; i < msix_entries; i++) {
@@ -1176,9 +1233,10 @@ static int ntb_setup_interrupts(struct ntb_device *ndev)
          */
         if (ndev->hw_type == BWD_HW)
                 writeq(~0, ndev->reg_ofs.ldb_mask);
-        else
-                writew(~(1 << ndev->limits.max_db_bits),
-                       ndev->reg_ofs.ldb_mask);
+        else {
+                u16 var = 1 << SNB_LINK_DB;
+                writew(~var, ndev->reg_ofs.ldb_mask);
+        }
 
         rc = ntb_setup_msix(ndev);
         if (!rc)
@@ -1286,6 +1344,39 @@ static void ntb_free_debugfs(struct ntb_device *ndev)
         }
 }
 
+static void ntb_hw_link_up(struct ntb_device *ndev)
+{
+        if (ndev->conn_type == NTB_CONN_TRANSPARENT)
+                ntb_link_event(ndev, NTB_LINK_UP);
+        else {
+                u32 ntb_cntl;
+
+                /* Let's bring the NTB link up */
+                ntb_cntl = readl(ndev->reg_ofs.lnk_cntl);
+                ntb_cntl &= ~(NTB_CNTL_LINK_DISABLE | NTB_CNTL_CFG_LOCK);
+                ntb_cntl |= NTB_CNTL_P2S_BAR23_SNOOP | NTB_CNTL_S2P_BAR23_SNOOP;
+                ntb_cntl |= NTB_CNTL_P2S_BAR45_SNOOP | NTB_CNTL_S2P_BAR45_SNOOP;
+                writel(ntb_cntl, ndev->reg_ofs.lnk_cntl);
+        }
+}
+
+static void ntb_hw_link_down(struct ntb_device *ndev)
+{
+        u32 ntb_cntl;
+
+        if (ndev->conn_type == NTB_CONN_TRANSPARENT) {
+                ntb_link_event(ndev, NTB_LINK_DOWN);
+                return;
+        }
+
+        /* Bring NTB link down */
+        ntb_cntl = readl(ndev->reg_ofs.lnk_cntl);
+        ntb_cntl &= ~(NTB_CNTL_P2S_BAR23_SNOOP | NTB_CNTL_S2P_BAR23_SNOOP);
+        ntb_cntl &= ~(NTB_CNTL_P2S_BAR45_SNOOP | NTB_CNTL_S2P_BAR45_SNOOP);
+        ntb_cntl |= NTB_CNTL_LINK_DISABLE | NTB_CNTL_CFG_LOCK;
+        writel(ntb_cntl, ndev->reg_ofs.lnk_cntl);
+}
+
 static int ntb_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 {
         struct ntb_device *ndev;
@@ -1374,9 +1465,7 @@ static int ntb_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
         if (rc)
                 goto err6;
 
-        /* Let's bring the NTB link up */
-        writel(NTB_CNTL_BAR23_SNOOP | NTB_CNTL_BAR45_SNOOP,
-               ndev->reg_ofs.lnk_cntl);
+        ntb_hw_link_up(ndev);
 
         return 0;
 
@@ -1406,12 +1495,8 @@ static void ntb_pci_remove(struct pci_dev *pdev)
 {
         struct ntb_device *ndev = pci_get_drvdata(pdev);
         int i;
-        u32 ntb_cntl;
 
-        /* Bring NTB link down */
-        ntb_cntl = readl(ndev->reg_ofs.lnk_cntl);
-        ntb_cntl |= NTB_CNTL_LINK_DISABLE;
-        writel(ntb_cntl, ndev->reg_ofs.lnk_cntl);
+        ntb_hw_link_down(ndev);
 
         ntb_transport_free(ndev->ntb_transport);