tg3: Workaround tagged status update bug

On rare occasions, writing the tag to the interrupt mailbox does not
reenable interrupts.  This patch fixes the problem by reissuing the
mailbox update.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Reviewed-by: Benjamin Li <benli@broadcom.com>
Signed-off-by: David S. Miller <davem@conan.davemloft.net>

diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c
index aa1d1defc820a7e542eb32d7f7944f655867829c..46352da36a8177c2a5c66f07dbe2ff579011a3d1 100644 (file)
--- a/drivers/net/tg3.c
+++ b/drivers/net/tg3.c
@@ -7754,6 +7754,9 @@ static void tg3_rings_reset(struct tg3 *tp)
 
        /* Disable interrupts */
        tw32_mailbox_f(tp->napi[0].int_mbox, 1);
+       tp->napi[0].chk_msi_cnt = 0;
+       tp->napi[0].last_rx_cons = 0;
+       tp->napi[0].last_tx_cons = 0;
 
        /* Zero mailbox registers. */
        if (tg3_flag(tp, SUPPORT_MSIX)) {
@@ -7764,6 +7767,9 @@ static void tg3_rings_reset(struct tg3 *tp)
                                tw32_mailbox(tp->napi[i].prodmbox, 0);
                        tw32_rx_mbox(tp->napi[i].consmbox, 0);
                        tw32_mailbox_f(tp->napi[i].int_mbox, 1);
+                       tp->napi[0].chk_msi_cnt = 0;
+                       tp->napi[i].last_rx_cons = 0;
+                       tp->napi[i].last_tx_cons = 0;
                }
                if (!tg3_flag(tp, ENABLE_TSS))
                        tw32_mailbox(tp->napi[0].prodmbox, 0);
@@ -8819,6 +8825,30 @@ static void tg3_periodic_fetch_stats(struct tg3 *tp)
        TG3_STAT_ADD32(&sp->rx_errors, RCVLPC_IN_ERRORS_CNT);
 }
 
+static void tg3_chk_missed_msi(struct tg3 *tp)
+{
+       u32 i;
+
+       for (i = 0; i < tp->irq_cnt; i++) {
+               struct tg3_napi *tnapi = &tp->napi[i];
+
+               if (tg3_has_work(tnapi)) {
+                       if (tnapi->last_rx_cons == tnapi->rx_rcb_ptr &&
+                           tnapi->last_tx_cons == tnapi->tx_cons) {
+                               if (tnapi->chk_msi_cnt < 1) {
+                                       tnapi->chk_msi_cnt++;
+                                       return;
+                               }
+                               tw32_mailbox(tnapi->int_mbox,
+                                            tnapi->last_tag << 24);
+                       }
+               }
+               tnapi->chk_msi_cnt = 0;
+               tnapi->last_rx_cons = tnapi->rx_rcb_ptr;
+               tnapi->last_tx_cons = tnapi->tx_cons;
+       }
+}
+
 static void tg3_timer(unsigned long __opaque)
 {
        struct tg3 *tp = (struct tg3 *) __opaque;
@@ -8828,6 +8858,10 @@ static void tg3_timer(unsigned long __opaque)
 
        spin_lock(&tp->lock);
 
+       if (GET_ASIC_REV(tp->pci_chip_rev_id) == ASIC_REV_5717 ||
+           GET_ASIC_REV(tp->pci_chip_rev_id) == ASIC_REV_57765)
+               tg3_chk_missed_msi(tp);
+
        if (!tg3_flag(tp, TAGGED_STATUS)) {
                /* All of this garbage is because when using non-tagged
                 * IRQ status the mailbox/status_block protocol the chip
@@ -9303,7 +9337,9 @@ static int tg3_open(struct net_device *dev)
                tg3_halt(tp, RESET_KIND_SHUTDOWN, 1);
                tg3_free_rings(tp);
        } else {
-               if (tg3_flag(tp, TAGGED_STATUS))
+               if (tg3_flag(tp, TAGGED_STATUS) &&
+                       GET_ASIC_REV(tp->pci_chip_rev_id) != ASIC_REV_5717 &&
+                       GET_ASIC_REV(tp->pci_chip_rev_id) != ASIC_REV_57765)
                        tp->timer_offset = HZ;
                else
                        tp->timer_offset = HZ / 10;

diff --git a/drivers/net/tg3.h b/drivers/net/tg3.h
index 5b3d2f34da7ae217bb6f3e33dd458774405d42f3..3c113c1e9d3517df0cfb5bb3f7a98703ccad7755 100644 (file)
--- a/drivers/net/tg3.h
+++ b/drivers/net/tg3.h
@@ -2800,6 +2800,7 @@ struct tg3_napi {
        struct tg3                      *tp;
        struct tg3_hw_status            *hw_status;
 
+       u32                             chk_msi_cnt;
        u32                             last_tag;
        u32                             last_irq_tag;
        u32                             int_mbox;
@@ -2807,6 +2808,7 @@ struct tg3_napi {
 
        u32                             consmbox ____cacheline_aligned;
        u32                             rx_rcb_ptr;
+       u32                             last_rx_cons;
        u16                             *rx_rcb_prod_idx;
        struct tg3_rx_prodring_set      prodring;
        struct tg3_rx_buffer_desc       *rx_rcb;
@@ -2814,6 +2816,7 @@ struct tg3_napi {
        u32                             tx_prod ____cacheline_aligned;
        u32                             tx_cons;
        u32                             tx_pending;
+       u32                             last_tx_cons;
        u32                             prodmbox;
        struct tg3_tx_buffer_desc       *tx_ring;
        struct ring_info                *tx_buffers;