Author: np
Date: Tue Jun 19 00:50:27 2018
New Revision: 335352
URL: https://svnweb.freebsd.org/changeset/base/335352

Log:
  cxgbe(4): Some mailbox commands require access to the Tx pipeline and
  can time out if it's backed up due to a non-stop deluge of PAUSE frames
  from a misbehaving peer.  Detect this situation and toggle MPS TxEn
  to allow forward progress.
  
  MFC after:    2 weeks
  Sponsored by: Chelsio Communications

Modified:
  head/sys/dev/cxgbe/common/t4_hw.c

Modified: head/sys/dev/cxgbe/common/t4_hw.c
==============================================================================
--- head/sys/dev/cxgbe/common/t4_hw.c   Tue Jun 19 00:38:28 2018        
(r335351)
+++ head/sys/dev/cxgbe/common/t4_hw.c   Tue Jun 19 00:50:27 2018        
(r335352)
@@ -239,6 +239,63 @@ static void fw_asrt(struct adapter *adap, struct fw_de
                  be32_to_cpu(asrt->u.assert.y));
 }
 
+struct port_tx_state {
+       uint64_t rx_pause;
+       uint64_t tx_frames;
+};
+
+static void
+read_tx_state_one(struct adapter *sc, int i, struct port_tx_state *tx_state)
+{
+       uint32_t rx_pause_reg, tx_frames_reg;
+
+       if (is_t4(sc)) {
+               tx_frames_reg = PORT_REG(i, A_MPS_PORT_STAT_TX_PORT_FRAMES_L);
+               rx_pause_reg = PORT_REG(i, A_MPS_PORT_STAT_RX_PORT_PAUSE_L);
+       } else {
+               tx_frames_reg = T5_PORT_REG(i, 
A_MPS_PORT_STAT_TX_PORT_FRAMES_L);
+               rx_pause_reg = T5_PORT_REG(i, A_MPS_PORT_STAT_RX_PORT_PAUSE_L);
+       }
+
+       tx_state->rx_pause = t4_read_reg64(sc, rx_pause_reg);
+       tx_state->tx_frames = t4_read_reg64(sc, tx_frames_reg);
+}
+
+static void
+read_tx_state(struct adapter *sc, struct port_tx_state *tx_state)
+{
+       int i;
+
+       for_each_port(sc, i)
+               read_tx_state_one(sc, i, &tx_state[i]);
+}
+
+static void
+check_tx_state(struct adapter *sc, struct port_tx_state *tx_state)
+{
+       uint32_t port_ctl_reg;
+       uint64_t tx_frames, rx_pause;
+       int i;
+
+       for_each_port(sc, i) {
+               rx_pause = tx_state[i].rx_pause;
+               tx_frames = tx_state[i].tx_frames;
+               read_tx_state_one(sc, i, &tx_state[i]); /* update */
+
+               if (is_t4(sc))
+                       port_ctl_reg = PORT_REG(i, A_MPS_PORT_CTL);
+               else
+                       port_ctl_reg = T5_PORT_REG(i, A_MPS_PORT_CTL);
+               if (t4_read_reg(sc, port_ctl_reg) & F_PORTTXEN &&
+                   rx_pause != tx_state[i].rx_pause &&
+                   tx_frames == tx_state[i].tx_frames) {
+                       t4_set_reg_field(sc, port_ctl_reg, F_PORTTXEN, 0);
+                       mdelay(1);
+                       t4_set_reg_field(sc, port_ctl_reg, F_PORTTXEN, 
F_PORTTXEN);
+               }
+       }
+}
+
 #define X_CIM_PF_NOACCESS 0xeeeeeeee
 /**
  *     t4_wr_mbox_meat_timeout - send a command to FW through the given mailbox
@@ -280,13 +337,14 @@ int t4_wr_mbox_meat_timeout(struct adapter *adap, int 
        };
        u32 v;
        u64 res;
-       int i, ms, delay_idx, ret;
+       int i, ms, delay_idx, ret, next_tx_check;
        const __be64 *p = cmd;
        u32 data_reg = PF_REG(mbox, A_CIM_PF_MAILBOX_DATA);
        u32 ctl_reg = PF_REG(mbox, A_CIM_PF_MAILBOX_CTRL);
        u32 ctl;
        __be64 cmd_rpl[MBOX_LEN/8];
        u32 pcie_fw;
+       struct port_tx_state tx_state[MAX_NPORTS];
 
        if (adap->flags & CHK_MBOX_ACCESS)
                ASSERT_SYNCHRONIZED_OP(adap);
@@ -375,8 +433,8 @@ int t4_wr_mbox_meat_timeout(struct adapter *adap, int 
        CH_DUMP_MBOX(adap, mbox, data_reg);
 
        t4_write_reg(adap, ctl_reg, F_MBMSGVALID | V_MBOWNER(X_MBOWNER_FW));
-       t4_read_reg(adap, ctl_reg);     /* flush write */
-
+       read_tx_state(adap, &tx_state[0]);      /* also flushes the write_reg */
+       next_tx_check = 1000;
        delay_idx = 0;
        ms = delay[0];
 
@@ -391,6 +449,12 @@ int t4_wr_mbox_meat_timeout(struct adapter *adap, int 
                        if (pcie_fw & F_PCIE_FW_ERR)
                                break;
                }
+
+               if (i >= next_tx_check) {
+                       check_tx_state(adap, &tx_state[0]);
+                       next_tx_check = i + 1000;
+               }
+
                if (sleep_ok) {
                        ms = delay[delay_idx];  /* last element may repeat */
                        if (delay_idx < ARRAY_SIZE(delay) - 1)
_______________________________________________
svn-src-all@freebsd.org mailing list
https://lists.freebsd.org/mailman/listinfo/svn-src-all
To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"

Reply via email to