cxgb4: fix large delays in PTP synchronization

 */

static int cxgb4_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)

{

	struct adapter *adapter = (struct adapter *)container_of(ptp,

				   struct adapter, ptp_clock_info);

	struct fw_ptp_cmd c;

	struct adapter *adapter = container_of(ptp, struct adapter,

					       ptp_clock_info);

	u64 ns;

	int err;

	memset(&c, 0, sizeof(c));

	c.op_to_portid = cpu_to_be32(FW_CMD_OP_V(FW_PTP_CMD) |

				     FW_CMD_REQUEST_F |

				     FW_CMD_READ_F |

				     FW_PTP_CMD_PORTID_V(0));

	c.retval_len16 = cpu_to_be32(FW_CMD_LEN16_V(sizeof(c) / 16));

	c.u.ts.sc = FW_PTP_SC_GET_TIME;

	err = t4_wr_mbox(adapter, adapter->mbox, &c, sizeof(c), &c);

	if (err < 0) {

		dev_err(adapter->pdev_dev,

			"PTP: %s error %d\n", __func__, -err);

		return err;

	}

	ns = t4_read_reg(adapter, T5_PORT_REG(0, MAC_PORT_PTP_SUM_LO_A));

	ns |= (u64)t4_read_reg(adapter,

			       T5_PORT_REG(0, MAC_PORT_PTP_SUM_HI_A)) << 32;

	/* convert to timespec*/

	ns = be64_to_cpu(c.u.ts.tm);

	*ts = ns_to_timespec64(ns);

	return err;

	return 0;

}

/**

#define MAC_PORT_CFG2_A 0x818

#define MAC_PORT_PTP_SUM_LO_A 0x990

#define MAC_PORT_PTP_SUM_HI_A 0x994

#define MPS_CMN_CTL_A	0x9000

#define COUNTPAUSEMCRX_S    5