cxgb3: Update Rev3 mac workaround

Update the heurstics workaround unlocking a hung mac:
- reduce Tx mac toggling by enabling Tx drain before resetting the mac
- Take Tx (lack of) activity in account only
- Update the monitoring counter range to 64 bits

Signed-off-by: Divy Le Ray <divy@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 33 insertions, 39 deletions

diff --git a/drivers/net/cxgb3/xgmac.c b/drivers/net/cxgb3/xgmac.c
index 9d7786937aad..4bd0901a97a6 100644
--- a/drivers/net/cxgb3/xgmac.c
+++ b/drivers/net/cxgb3/xgmac.c
@@ -150,7 +150,8 @@ int t3_mac_reset(struct cmac *mac)
 static int t3b2_mac_reset(struct cmac *mac)
 {
         struct adapter *adap = mac->adapter;
-        unsigned int oft = mac->offset;
+        unsigned int oft = mac->offset, store;
+        int idx = macidx(mac);
         u32 val;
 
         if (!macidx(mac))
@@ -158,14 +159,28 @@ static int t3b2_mac_reset(struct cmac *mac)
         else
                 t3_set_reg_field(adap, A_MPS_CFG, F_PORT1ACTIVE, 0);
 
+        /* Stop NIC traffic to reduce the number of TXTOGGLES */
+        t3_set_reg_field(adap, A_MPS_CFG, F_ENFORCEPKT, 0);
+        /* Ensure TX drains */
+        t3_set_reg_field(adap, A_XGM_TX_CFG + oft, F_TXPAUSEEN, 0);
+
         t3_write_reg(adap, A_XGM_RESET_CTRL + oft, F_MAC_RESET_);
         t3_read_reg(adap, A_XGM_RESET_CTRL + oft);    /* flush */
 
+        /* Store A_TP_TX_DROP_CFG_CH0 */
+        t3_write_reg(adap, A_TP_PIO_ADDR, A_TP_TX_DROP_CFG_CH0 + idx);
+        store = t3_read_reg(adap, A_TP_TX_DROP_CFG_CH0 + idx);
+
         msleep(10);
 
+        /* Change DROP_CFG to 0xc0000011 */
+        t3_write_reg(adap, A_TP_PIO_ADDR, A_TP_TX_DROP_CFG_CH0 + idx);
+        t3_write_reg(adap, A_TP_PIO_DATA, 0xc0000011);
+
         /* Check for xgm Rx fifo empty */
+        /* Increased loop count to 1000 from 5 cover 1G and 100Mbps case */
         if (t3_wait_op_done(adap, A_XGM_RX_MAX_PKT_SIZE_ERR_CNT + oft,
-                            0x80000000, 1, 5, 2)) {
+                            0x80000000, 1, 1000, 2)) {
                 CH_ERR(adap, "MAC %d Rx fifo drain failed\n",
                        macidx(mac));
                 return -1;
@@ -191,11 +206,18 @@ static int t3b2_mac_reset(struct cmac *mac)
                      F_DISPAUSEFRAMES | F_EN1536BFRAMES |
                      F_RMFCS | F_ENJUMBO | F_ENHASHMCAST);
 
-        if (!macidx(mac))
+        /* Restore the DROP_CFG */
+        t3_write_reg(adap, A_TP_PIO_ADDR, A_TP_TX_DROP_CFG_CH0 + idx);
+        t3_write_reg(adap, A_TP_PIO_DATA, store);
+
+        if (!idx)
                 t3_set_reg_field(adap, A_MPS_CFG, 0, F_PORT0ACTIVE);
         else
                 t3_set_reg_field(adap, A_MPS_CFG, 0, F_PORT1ACTIVE);
 
+        /* re-enable nic traffic */
+        t3_set_reg_field(adap, A_MPS_CFG, F_ENFORCEPKT, 1);
+
         return 0;
 }
 
@@ -332,15 +354,6 @@ int t3_mac_set_mtu(struct cmac *mac, unsigned int mtu)
                 return -EINVAL;
         t3_write_reg(adap, A_XGM_RX_MAX_PKT_SIZE + mac->offset, mtu);
 
-        /*
-         * Adjust the PAUSE frame watermarks.  We always set the LWM, and the
-         * HWM only if flow-control is enabled.
-         */
-        hwm = max_t(unsigned int, MAC_RXFIFO_SIZE - 3 * mtu,
-                    MAC_RXFIFO_SIZE * 38 / 100);
-        hwm = min(hwm, MAC_RXFIFO_SIZE - 8192);
-        lwm = min(3 * (int)mtu, MAC_RXFIFO_SIZE / 4);
-
         if (adap->params.rev >= T3_REV_B2 &&
             (t3_read_reg(adap, A_XGM_RX_CTRL + mac->offset) & F_RXEN)) {
                 disable_exact_filters(mac);
@@ -452,9 +465,12 @@ int t3_mac_enable(struct cmac *mac, int which)
 
         if (which & MAC_DIRECTION_TX) {
                 t3_write_reg(adap, A_TP_PIO_ADDR, A_TP_TX_DROP_CFG_CH0 + idx);
-                t3_write_reg(adap, A_TP_PIO_DATA, 0xc0ede401);
+                t3_write_reg(adap, A_TP_PIO_DATA,
+                             adap->params.rev == T3_REV_C ?
+                             0xc4ffff01 : 0xc0ede401);
                 t3_write_reg(adap, A_TP_PIO_ADDR, A_TP_TX_DROP_MODE);
-                t3_set_reg_field(adap, A_TP_PIO_DATA, 1 << idx, 1 << idx);
+                t3_set_reg_field(adap, A_TP_PIO_DATA, 1 << idx,
+                                 adap->params.rev == T3_REV_C ? 0 : 1 << idx);
 
                 t3_write_reg(adap, A_XGM_TX_CTRL + oft, F_TXEN);
 
@@ -510,15 +526,12 @@ int t3b2_mac_watchdog_task(struct cmac *mac)
         struct adapter *adap = mac->adapter;
         struct mac_stats *s = &mac->stats;
         unsigned int tx_tcnt, tx_xcnt;
-        unsigned int tx_mcnt = s->tx_frames;
-        unsigned int rx_mcnt = s->rx_frames;
-        unsigned int rx_xcnt;
+        u64 tx_mcnt = s->tx_frames;
         int status;
 
         status = 0;
         tx_xcnt = 1;            /* By default tx_xcnt is making progress */
         tx_tcnt = mac->tx_tcnt; /* If tx_mcnt is progressing ignore tx_tcnt */
-        rx_xcnt = 1;            /* By default rx_xcnt is making progress */
         if (tx_mcnt == mac->tx_mcnt && mac->rx_pause == s->rx_pause) {
                 tx_xcnt = (G_TXSPI4SOPCNT(t3_read_reg(adap,
                                                 A_XGM_TX_SPI4_SOP_EOP_CNT +
@@ -529,11 +542,11 @@ int t3b2_mac_watchdog_task(struct cmac *mac)
                         tx_tcnt = (G_TXDROPCNTCH0RCVD(t3_read_reg(adap,
                                                       A_TP_PIO_DATA)));
                 } else {
-                        goto rxcheck;
+                        goto out;
                 }
         } else {
                 mac->toggle_cnt = 0;
-                goto rxcheck;
+                goto out;
         }
 
         if ((tx_tcnt != mac->tx_tcnt) && (mac->tx_xcnt == 0)) {
@@ -546,23 +559,6 @@ int t3b2_mac_watchdog_task(struct cmac *mac)
                 }
         } else {
                 mac->toggle_cnt = 0;
-                goto rxcheck;
-        }
-
-rxcheck:
-        if (rx_mcnt != mac->rx_mcnt) {
-                rx_xcnt = (G_TXSPI4SOPCNT(t3_read_reg(adap,
-                                                A_XGM_RX_SPI4_SOP_EOP_CNT +
-                                                mac->offset))) +
-                                                (s->rx_fifo_ovfl -
-                                                 mac->rx_ocnt);
-                mac->rx_ocnt = s->rx_fifo_ovfl;
-        } else
-                goto out;
-
-        if (mac->rx_mcnt != s->rx_frames && rx_xcnt == 0 &&
-            mac->rx_xcnt == 0) {
-                status = 2;
                 goto out;
         }
 
@@ -570,8 +566,6 @@ out:
         mac->tx_tcnt = tx_tcnt;
         mac->tx_xcnt = tx_xcnt;
         mac->tx_mcnt = s->tx_frames;
-        mac->rx_xcnt = rx_xcnt;
-        mac->rx_mcnt = s->rx_frames;
         mac->rx_pause = s->rx_pause;
         if (status == 1) {
                 t3_write_reg(adap, A_XGM_TX_CTRL + mac->offset, 0);