1 files changed, 44 insertions, 11 deletions

diff --git a/drivers/net/ethernet/sfc/mcdi.c b/drivers/net/ethernet/sfc/mcdi.c
index 7bd4b14bf3b3..5239cf9bdc56 100644
--- a/drivers/net/ethernet/sfc/mcdi.c
+++ b/drivers/net/ethernet/sfc/mcdi.c
@@ -52,12 +52,7 @@ static void efx_mcdi_timeout_async(unsigned long context);
 static int efx_mcdi_drv_attach(struct efx_nic *efx, bool driver_operating,
                                bool *was_attached_out);
 static bool efx_mcdi_poll_once(struct efx_nic *efx);
-
-static inline struct efx_mcdi_iface *efx_mcdi(struct efx_nic *efx)
-{
-        EFX_BUG_ON_PARANOID(!efx->mcdi);
-        return &efx->mcdi->iface;
-}
+static void efx_mcdi_abandon(struct efx_nic *efx);
 
 int efx_mcdi_init(struct efx_nic *efx)
 {
@@ -558,6 +553,8 @@ static int _efx_mcdi_rpc_finish(struct efx_nic *efx, unsigned cmd, size_t inlen,
                         rc = 0;
                 }
 
+                efx_mcdi_abandon(efx);
+
                 /* Close the race with efx_mcdi_ev_cpl() executing just too late
                  * and completing a request we've just cancelled, by ensuring
                  * that the seqno check therein fails.
@@ -672,6 +669,9 @@ int efx_mcdi_rpc_start(struct efx_nic *efx, unsigned cmd,
         if (efx->mc_bist_for_other_fn)
                 return -ENETDOWN;
 
+        if (mcdi->mode == MCDI_MODE_FAIL)
+                return -ENETDOWN;
+
         efx_mcdi_acquire_sync(mcdi);
         efx_mcdi_send_request(efx, cmd, inbuf, inlen);
         return 0;
@@ -812,7 +812,11 @@ void efx_mcdi_mode_poll(struct efx_nic *efx)
                 return;
 
         mcdi = efx_mcdi(efx);
-        if (mcdi->mode == MCDI_MODE_POLL)
+        /* If already in polling mode, nothing to do.
+         * If in fail-fast state, don't switch to polled completion.
+         * FLR recovery will do that later.
+         */
+        if (mcdi->mode == MCDI_MODE_POLL || mcdi->mode == MCDI_MODE_FAIL)
                 return;
 
         /* We can switch from event completion to polled completion, because
@@ -841,8 +845,8 @@ void efx_mcdi_flush_async(struct efx_nic *efx)
 
         mcdi = efx_mcdi(efx);
 
-        /* We must be in polling mode so no more requests can be queued */
-        BUG_ON(mcdi->mode != MCDI_MODE_POLL);
+        /* We must be in poll or fail mode so no more requests can be queued */
+        BUG_ON(mcdi->mode == MCDI_MODE_EVENTS);
 
         del_timer_sync(&mcdi->async_timer);
 
@@ -875,8 +879,11 @@ void efx_mcdi_mode_event(struct efx_nic *efx)
                 return;
 
         mcdi = efx_mcdi(efx);
-
-        if (mcdi->mode == MCDI_MODE_EVENTS)
+        /* If already in event completion mode, nothing to do.
+         * If in fail-fast state, don't switch to event completion.  FLR
+         * recovery will do that later.
+         */
+        if (mcdi->mode == MCDI_MODE_EVENTS || mcdi->mode == MCDI_MODE_FAIL)
                 return;
 
         /* We can't switch from polled to event completion in the middle of a
@@ -966,6 +973,19 @@ static void efx_mcdi_ev_bist(struct efx_nic *efx)
         spin_unlock(&mcdi->iface_lock);
 }
 
+/* MCDI timeouts seen, so make all MCDI calls fail-fast and issue an FLR to try
+ * to recover.
+ */
+static void efx_mcdi_abandon(struct efx_nic *efx)
+{
+        struct efx_mcdi_iface *mcdi = efx_mcdi(efx);
+
+        if (xchg(&mcdi->mode, MCDI_MODE_FAIL) == MCDI_MODE_FAIL)
+                return; /* it had already been done */
+        netif_dbg(efx, hw, efx->net_dev, "MCDI is timing out; trying to recover\n");
+        efx_schedule_reset(efx, RESET_TYPE_MCDI_TIMEOUT);
+}
+
 /* Called from  falcon_process_eventq for MCDI events */
 void efx_mcdi_process_event(struct efx_channel *channel,
                             efx_qword_t *event)
@@ -1512,6 +1532,19 @@ int efx_mcdi_reset(struct efx_nic *efx, enum reset_type method)
 {
         int rc;
 
+        /* If MCDI is down, we can't handle_assertion */
+        if (method == RESET_TYPE_MCDI_TIMEOUT) {
+                rc = pci_reset_function(efx->pci_dev);
+                if (rc)
+                        return rc;
+                /* Re-enable polled MCDI completion */
+                if (efx->mcdi) {
+                        struct efx_mcdi_iface *mcdi = efx_mcdi(efx);
+                        mcdi->mode = MCDI_MODE_POLL;
+                }
+                return 0;
+        }
+
         /* Recover from a failed assertion pre-reset */
         rc = efx_mcdi_handle_assertion(efx);
         if (rc)