qed: Correct slowpath interrupt scheme

When using INTa, ISR might be called before device is configured
for INTa [E.g., due to other device asserting the shared interrupt line],
in which case the ISR would read the SISR registers that shouldn't be
read unless HW is already configured for INTa. This might break interrupts
later on. There's also an MSI-X issue due to this difference, although
it's mostly theoretical.

This patch changes the initialization order, calling request_irq() for the
slowpath interrupt only after the chip is configured for working
in the preferred interrupt mode.

Signed-off-by: Sudarsana Kalluru <Sudarsana.Kalluru@qlogic.com>
Signed-off-by: Manish Chopra <manish.chopra@qlogic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/qlogic/qed/qed.h b/drivers/net/ethernet/qlogic/qed/qed.h
index ac17d8669b1adad9291a6a39646b51ff80693176..1292c360390cd79d532ca155158858bd630648d5 100644 (file)
--- a/drivers/net/ethernet/qlogic/qed/qed.h
+++ b/drivers/net/ethernet/qlogic/qed/qed.h
@@ -299,6 +299,7 @@ struct qed_hwfn {
 
        /* Flag indicating whether interrupts are enabled or not*/
        bool                            b_int_enabled;
+       bool                            b_int_requested;
 
        struct qed_mcp_info             *mcp_info;
 
@@ -491,6 +492,8 @@ u32 qed_unzip_data(struct qed_hwfn *p_hwfn,
                   u32 input_len, u8 *input_buf,
                   u32 max_size, u8 *unzip_buf);
 
+int qed_slowpath_irq_req(struct qed_hwfn *hwfn);
+
 #define QED_ETH_INTERFACE_VERSION       300
 
 #endif /* _QED_H */

diff --git a/drivers/net/ethernet/qlogic/qed/qed_int.c b/drivers/net/ethernet/qlogic/qed/qed_int.c
index de50e84902afe3b6a26c422d34a687ec9bc523ec..9cc9d62c1fec64844eba85ca10213a77d3158227 100644 (file)
--- a/drivers/net/ethernet/qlogic/qed/qed_int.c
+++ b/drivers/net/ethernet/qlogic/qed/qed_int.c
@@ -783,22 +783,16 @@ void qed_int_igu_enable_int(struct qed_hwfn *p_hwfn,
        qed_wr(p_hwfn, p_ptt, IGU_REG_PF_CONFIGURATION, igu_pf_conf);
 }
 
-void qed_int_igu_enable(struct qed_hwfn *p_hwfn,
-                       struct qed_ptt *p_ptt,
-                       enum qed_int_mode int_mode)
+int qed_int_igu_enable(struct qed_hwfn *p_hwfn, struct qed_ptt *p_ptt,
+                      enum qed_int_mode int_mode)
 {
-       int i;
-
-       p_hwfn->b_int_enabled = 1;
+       int rc, i;
 
        /* Mask non-link attentions */
        for (i = 0; i < 9; i++)
                qed_wr(p_hwfn, p_ptt,
                       MISC_REG_AEU_ENABLE1_IGU_OUT_0 + (i << 2), 0);
 
-       /* Enable interrupt Generation */
-       qed_int_igu_enable_int(p_hwfn, p_ptt, int_mode);
-
        /* Configure AEU signal change to produce attentions for link */
        qed_wr(p_hwfn, p_ptt, IGU_REG_LEADING_EDGE_LATCH, 0xfff);
        qed_wr(p_hwfn, p_ptt, IGU_REG_TRAILING_EDGE_LATCH, 0xfff);
@@ -808,6 +802,19 @@ void qed_int_igu_enable(struct qed_hwfn *p_hwfn,
 
        /* Unmask AEU signals toward IGU */
        qed_wr(p_hwfn, p_ptt, MISC_REG_AEU_MASK_ATTN_IGU, 0xff);
+       if ((int_mode != QED_INT_MODE_INTA) || IS_LEAD_HWFN(p_hwfn)) {
+               rc = qed_slowpath_irq_req(p_hwfn);
+               if (rc != 0) {
+                       DP_NOTICE(p_hwfn, "Slowpath IRQ request failed\n");
+                       return -EINVAL;
+               }
+               p_hwfn->b_int_requested = true;
+       }
+       /* Enable interrupt Generation */
+       qed_int_igu_enable_int(p_hwfn, p_ptt, int_mode);
+       p_hwfn->b_int_enabled = 1;
+
+       return rc;
 }
 
 void qed_int_igu_disable_int(struct qed_hwfn *p_hwfn,
@@ -1127,3 +1134,11 @@ int qed_int_get_num_sbs(struct qed_hwfn *p_hwfn,
 
        return info->igu_sb_cnt;
 }
+
+void qed_int_disable_post_isr_release(struct qed_dev *cdev)
+{
+       int i;
+
+       for_each_hwfn(cdev, i)
+               cdev->hwfns[i].b_int_requested = false;
+}

diff --git a/drivers/net/ethernet/qlogic/qed/qed_int.h b/drivers/net/ethernet/qlogic/qed/qed_int.h
index 16b57518e706728dde646688fb059a3f8f88bb97..51e0b09a7f47d3da8ca9c1d2d0982aa2e77d51f4 100644 (file)
--- a/drivers/net/ethernet/qlogic/qed/qed_int.h
+++ b/drivers/net/ethernet/qlogic/qed/qed_int.h
@@ -169,10 +169,14 @@ int qed_int_get_num_sbs(struct qed_hwfn *p_hwfn,
                        int *p_iov_blks);
 
 /**
- * @file
+ * @brief qed_int_disable_post_isr_release - performs the cleanup post ISR
+ *        release. The API need to be called after releasing all slowpath IRQs
+ *        of the device.
+ *
+ * @param cdev
  *
- * @brief Interrupt handler
  */
+void qed_int_disable_post_isr_release(struct qed_dev *cdev);
 
 #define QED_CAU_DEF_RX_TIMER_RES 0
 #define QED_CAU_DEF_TX_TIMER_RES 0
@@ -366,10 +370,11 @@ void qed_int_setup(struct qed_hwfn *p_hwfn,
  * @param p_hwfn
  * @param p_ptt
  * @param int_mode
+ *
+ * @return int
  */
-void qed_int_igu_enable(struct qed_hwfn *p_hwfn,
-                       struct qed_ptt *p_ptt,
-                       enum qed_int_mode int_mode);
+int qed_int_igu_enable(struct qed_hwfn *p_hwfn, struct qed_ptt *p_ptt,
+                      enum qed_int_mode int_mode);
 
 /**
  * @brief - Initialize CAU status block entry

diff --git a/drivers/net/ethernet/qlogic/qed/qed_main.c b/drivers/net/ethernet/qlogic/qed/qed_main.c
index 947c7af72b25b32db163dc3ea47ca7d63db50490..174f7341c5c32c2bbcf81391b02f6d9a6d9327c2 100644 (file)
--- a/drivers/net/ethernet/qlogic/qed/qed_main.c
+++ b/drivers/net/ethernet/qlogic/qed/qed_main.c
@@ -476,41 +476,22 @@ static irqreturn_t qed_single_int(int irq, void *dev_instance)
        return rc;
 }
 
-static int qed_slowpath_irq_req(struct qed_dev *cdev)
+int qed_slowpath_irq_req(struct qed_hwfn *hwfn)
 {
-       int i = 0, rc = 0;
+       struct qed_dev *cdev = hwfn->cdev;
+       int rc = 0;
+       u8 id;
 
        if (cdev->int_params.out.int_mode == QED_INT_MODE_MSIX) {
-               /* Request all the slowpath MSI-X vectors */
-               for (i = 0; i < cdev->num_hwfns; i++) {
-                       snprintf(cdev->hwfns[i].name, NAME_SIZE,
-                                "sp-%d-%02x:%02x.%02x",
-                                i, cdev->pdev->bus->number,
-                                PCI_SLOT(cdev->pdev->devfn),
-                                cdev->hwfns[i].abs_pf_id);
-
-                       rc = request_irq(cdev->int_params.msix_table[i].vector,
-                                        qed_msix_sp_int, 0,
-                                        cdev->hwfns[i].name,
-                                        cdev->hwfns[i].sp_dpc);
-                       if (rc)
-                               break;
-
-                       DP_VERBOSE(&cdev->hwfns[i],
-                                  (NETIF_MSG_INTR | QED_MSG_SP),
+               id = hwfn->my_id;
+               snprintf(hwfn->name, NAME_SIZE, "sp-%d-%02x:%02x.%02x",
+                        id, cdev->pdev->bus->number,
+                        PCI_SLOT(cdev->pdev->devfn), hwfn->abs_pf_id);
+               rc = request_irq(cdev->int_params.msix_table[id].vector,
+                                qed_msix_sp_int, 0, hwfn->name, hwfn->sp_dpc);
+               if (!rc)
+                       DP_VERBOSE(hwfn, (NETIF_MSG_INTR | QED_MSG_SP),
                                   "Requested slowpath MSI-X\n");
-               }
-
-               if (i != cdev->num_hwfns) {
-                       /* Free already request MSI-X vectors */
-                       for (i--; i >= 0; i--) {
-                               unsigned int vec =
-                                       cdev->int_params.msix_table[i].vector;
-                               synchronize_irq(vec);
-                               free_irq(cdev->int_params.msix_table[i].vector,
-                                        cdev->hwfns[i].sp_dpc);
-                       }
-               }
        } else {
                unsigned long flags = 0;
 
@@ -534,13 +515,17 @@ static void qed_slowpath_irq_free(struct qed_dev *cdev)
 
        if (cdev->int_params.out.int_mode == QED_INT_MODE_MSIX) {
                for_each_hwfn(cdev, i) {
+                       if (!cdev->hwfns[i].b_int_requested)
+                               break;
                        synchronize_irq(cdev->int_params.msix_table[i].vector);
                        free_irq(cdev->int_params.msix_table[i].vector,
                                 cdev->hwfns[i].sp_dpc);
                }
        } else {
-               free_irq(cdev->pdev->irq, cdev);
+               if (QED_LEADING_HWFN(cdev)->b_int_requested)
+                       free_irq(cdev->pdev->irq, cdev);
        }
+       qed_int_disable_post_isr_release(cdev);
 }
 
 static int qed_nic_stop(struct qed_dev *cdev)
@@ -765,16 +750,11 @@ static int qed_slowpath_start(struct qed_dev *cdev,
        if (rc)
                goto err1;
 
-       /* Request the slowpath IRQ */
-       rc = qed_slowpath_irq_req(cdev);
-       if (rc)
-               goto err2;
-
        /* Allocate stream for unzipping */
        rc = qed_alloc_stream_mem(cdev);
        if (rc) {
                DP_NOTICE(cdev, "Failed to allocate stream memory\n");
-               goto err3;
+               goto err2;
        }
 
        /* Start the slowpath */