S2io: Enable msi-x link interrupts.

- Enable msi-x link interrupts because the timer based scheduler was getting
cancelled causing the link state to be lost with repetitive card up/downs
when changing the mtu.
- Unmask mac_rmac_link interrupts only for Xframe I and prevent a spurious
link interrupt in Xframe II.
- Stop the tx queue and indicate link down when card is down

Signed-off-by: Santosh Rastapur <santosh.rastapur@neterion.com>
Signed-off-by: Ramkrishna Vepa <ram.vepa@neterion.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

drivers/net/s2io.c

@@ -1891,8 +1891,6 @@ static int init_nic(struct s2io_nic *nic)
 
 static int s2io_link_fault_indication(struct s2io_nic *nic)
 {
-	if (nic->config.intr_type != INTA)
-		return MAC_RMAC_ERR_TIMER;
 	if (nic->device_type == XFRAME_II_DEVICE)
 		return LINK_UP_DOWN_INTERRUPT;
 	else
@@ -1925,7 +1923,9 @@ static void en_dis_err_alarms(struct s2io_nic *nic, u16 mask, int flag)
 {
 	struct XENA_dev_config __iomem *bar0 = nic->bar0;
 	register u64 gen_int_mask = 0;
+	u64 interruptible;
 
+	writeq(DISABLE_ALL_INTRS, &bar0->general_int_mask);
 	if (mask & TX_DMA_INTR) {
 
 		gen_int_mask |= TXDMA_INT_M;
@@ -2015,10 +2015,12 @@ static void en_dis_err_alarms(struct s2io_nic *nic, u16 mask, int flag)
 		gen_int_mask |= RXMAC_INT_M;
 		do_s2io_write_bits(MAC_INT_STATUS_RMAC_INT, flag,
 				&bar0->mac_int_mask);
-		do_s2io_write_bits(RMAC_RX_BUFF_OVRN | RMAC_RX_SM_ERR |
+		interruptible = RMAC_RX_BUFF_OVRN | RMAC_RX_SM_ERR |
 				RMAC_UNUSED_INT | RMAC_SINGLE_ECC_ERR |
-				RMAC_DOUBLE_ECC_ERR |
-				RMAC_LINK_STATE_CHANGE_INT,
+				RMAC_DOUBLE_ECC_ERR;
+		if (s2io_link_fault_indication(nic) == MAC_RMAC_ERR_TIMER)
+			interruptible |= RMAC_LINK_STATE_CHANGE_INT;
+		do_s2io_write_bits(interruptible,
 				flag, &bar0->mac_rmac_err_mask);
 	}
 
@@ -4376,18 +4378,24 @@ static irqreturn_t s2io_msix_fifo_handle(int irq, void *dev_id)
 		/* Nothing much can be done. Get out */
 		return IRQ_HANDLED;
 
-	writeq(S2IO_MINUS_ONE, &bar0->general_int_mask);
+	if (reason & (GEN_INTR_TXPIC | GEN_INTR_TXTRAFFIC)) {
+		writeq(S2IO_MINUS_ONE, &bar0->general_int_mask);
 
-	if (reason & GEN_INTR_TXTRAFFIC)
-		writeq(S2IO_MINUS_ONE, &bar0->tx_traffic_int);
+		if (reason & GEN_INTR_TXPIC)
+			s2io_txpic_intr_handle(sp);
 
-	for (i = 0; i < config->tx_fifo_num; i++)
-		tx_intr_handler(&fifos[i]);
+		if (reason & GEN_INTR_TXTRAFFIC)
+			writeq(S2IO_MINUS_ONE, &bar0->tx_traffic_int);
 
-	writeq(sp->general_int_mask, &bar0->general_int_mask);
-	readl(&bar0->general_int_status);
+		for (i = 0; i < config->tx_fifo_num; i++)
+			tx_intr_handler(&fifos[i]);
 
-	return IRQ_HANDLED;
+		writeq(sp->general_int_mask, &bar0->general_int_mask);
+		readl(&bar0->general_int_status);
+		return IRQ_HANDLED;
+	}
+	/* The interrupt was not raised by us */
+	return IRQ_NONE;
 }
 
 static void s2io_txpic_intr_handle(struct s2io_nic *sp)
@@ -7115,6 +7123,9 @@ static void do_s2io_card_down(struct s2io_nic * sp, int do_io)
 
 	s2io_rem_isr(sp);
 
+	/* stop the tx queue, indicate link down */
+	s2io_link(sp, LINK_DOWN);
+
 	/* Check if the device is Quiescent and then Reset the NIC */
 	while(do_io) {
 		/* As per the HW requirement we need to replenish the
@@ -7247,17 +7258,19 @@ static int s2io_card_up(struct s2io_nic * sp)
 
 	S2IO_TIMER_CONF(sp->alarm_timer, s2io_alarm_handle, sp, (HZ/2));
 
+	set_bit(__S2IO_STATE_CARD_UP, &sp->state);
+
 	/*  Enable select interrupts */
 	en_dis_err_alarms(sp, ENA_ALL_INTRS, ENABLE_INTRS);
-	if (sp->config.intr_type != INTA)
-		en_dis_able_nic_intrs(sp, TX_TRAFFIC_INTR, ENABLE_INTRS);
-	else {
+	if (sp->config.intr_type != INTA) {
+		interruptible = TX_TRAFFIC_INTR | TX_PIC_INTR;
+		en_dis_able_nic_intrs(sp, interruptible, ENABLE_INTRS);
+	} else {
 		interruptible = TX_TRAFFIC_INTR | RX_TRAFFIC_INTR;
 		interruptible |= TX_PIC_INTR;
 		en_dis_able_nic_intrs(sp, interruptible, ENABLE_INTRS);
 	}
 
-	set_bit(__S2IO_STATE_CARD_UP, &sp->state);
 	return 0;
 }
 

drivers/net/s2io.h

@@ -1107,6 +1107,7 @@ static int init_shared_mem(struct s2io_nic *sp);
 static void free_shared_mem(struct s2io_nic *sp);
 static int init_nic(struct s2io_nic *nic);
 static int rx_intr_handler(struct ring_info *ring_data, int budget);
+static void s2io_txpic_intr_handle(struct s2io_nic *sp);
 static void tx_intr_handler(struct fifo_info *fifo_data);
 static void s2io_handle_errors(void * dev_id);