Re: [PATCH v4 08/10] net: eth: altera: add support for ptp and timestamping

On Wed, Jul 08, 2020 at 03:23:59PM +0800, Ooi, Joyce wrote:

Need to handle case where priv->ptp_priv.ptp_clock == NULL.

+		info->so_timestamping = SOF_TIMESTAMPING_TX_HARDWARE |
+					SOF_TIMESTAMPING_RX_HARDWARE |
+					SOF_TIMESTAMPING_RAW_HARDWARE;
+
+		info->tx_types = (1 << HWTSTAMP_TX_OFF) |
+						 (1 << HWTSTAMP_TX_ON);

No need to break statement.  This fits nicely on one line.

+
+		info->rx_filters = (1 << HWTSTAMP_FILTER_NONE) |
+						   (1 << HWTSTAMP_FILTER_ALL);
+
+		return 0;
+	} else {

No need for else block.

+		return ethtool_op_get_ts_info(dev, info);
+	}
+}
+
 static const struct ethtool_ops tse_ethtool_ops = {
 	.get_drvinfo = tse_get_drvinfo,
 	.get_regs_len = tse_reglen,

Need to check here for phy_has_hwtstamp() and pass through to PHY
layer if true.

+
+	if (!netif_running(dev))
+		return -EINVAL;
+
+	if (!priv->ptp_enable)	{
+		netdev_alert(priv->dev, "Timestamping not supported");
+		return -EOPNOTSUPP;
+	}
+
+	if (cmd == SIOCSHWTSTAMP) {
+		if (copy_from_user(&config, ifr->ifr_data,
+				   sizeof(struct hwtstamp_config)))
+			return -EFAULT;
+
+		if (config.flags)
+			return -EINVAL;
+
+		switch (config.tx_type) {
+		case HWTSTAMP_TX_OFF:
+			priv->hwts_tx_en = 0;
+			break;
+		case HWTSTAMP_TX_ON:
+			priv->hwts_tx_en = 1;
+			break;
+		default:
+			return -ERANGE;
+		}
+
+		switch (config.rx_filter) {
+		case HWTSTAMP_FILTER_NONE:
+			priv->hwts_rx_en = 0;
+			config.rx_filter = HWTSTAMP_FILTER_NONE;
+			break;
+		default:
+			priv->hwts_rx_en = 1;
+			config.rx_filter = HWTSTAMP_FILTER_ALL;
+			break;
+		}
+
+		if (copy_to_user(ifr->ifr_data, &config,
+				 sizeof(struct hwtstamp_config)))
+			return -EFAULT;
+		else
+			return 0;
+	}
+
+	if (cmd == SIOCGHWTSTAMP) {
+		config.flags = 0;
+
+		if (priv->hwts_tx_en)
+			config.tx_type = HWTSTAMP_TX_ON;
+		else
+			config.tx_type = HWTSTAMP_TX_OFF;
+
+		if (priv->hwts_rx_en)
+			config.rx_filter = HWTSTAMP_FILTER_ALL;
+		else
+			config.rx_filter = HWTSTAMP_FILTER_NONE;
+
+		if (copy_to_user(ifr->ifr_data, &config,
+				 sizeof(struct hwtstamp_config)))
+			return -EFAULT;
+		else
+			return 0;
+	}
+
+	if (!dev->phydev)
+		return -EINVAL;
+
+	return phy_mii_ioctl(dev->phydev, ifr, cmd);
+}
+
 static struct net_device_ops altera_tse_netdev_ops = {
 	.ndo_open		= tse_open,
 	.ndo_stop		= tse_shutdown,

The name "ptp_enable" is a poor choice.  It sounds like something that
can be enabled at run time.  Suggest "has_ptp" instead.

+	dev_info(&pdev->dev, "PTP Enable: %d\n", priv->ptp_enable);
+
+	if (priv->ptp_enable) {
+		/* MAP PTP */
+		ret = intel_fpga_tod_probe(pdev, &priv->ptp_priv);
+		if (ret) {
+			dev_err(&pdev->dev, "cannot map PTP\n");
+			goto err_init_phy;
+		}
+		ret = intel_fpga_tod_register(&priv->ptp_priv,
+					      priv->device);
+		if (ret) {
+			dev_err(&pdev->dev, "Failed to register PTP clock\n");
+			ret = -ENXIO;
+			goto err_init_phy;
+		}
+	}
+
 	return 0;
 
 err_init_phy:

+/* Initialize PTP control block registers */
+int intel_fpga_tod_init(struct intel_fpga_tod_private *priv)
+{
+	struct timespec64 now;
+	int ret = 0;
+
+	ret = intel_fpga_tod_adjust_fine(&priv->ptp_clock_ops, 0l);

Why clobber a learned frequency offset here?  If user space closes
then re-opens, then it expects the old frequency to be preserved.

It is fine to set this to zero when the driver loads, but not after.

+	if (ret != 0)
+		goto out;
+
+	/* Initialize the hardware clock to the system time */
+	ktime_get_real_ts64(&now);

Please initialize to zero instead, as some people prefer it that way.

(But only the first time when the driver loads!)

+	intel_fpga_tod_set_time(&priv->ptp_clock_ops, &now);
+
+	spin_lock_init(&priv->tod_lock);
+
+out:
+	return ret;
+}

Thanks,
Richard