Re: [PATCH net-next 3/5] net: bcmasp: Add support for ASP2.0 Ethernet controller

From: Andrew Lunn
Date: Sat Sep 25 2021 - 12:45:46 EST


> +static int bcmasp_probe(struct platform_device *pdev)
> +{
> + struct bcmasp_priv *priv;
> + struct device_node *ports_node, *intf_node;
> + struct device *dev = &pdev->dev;
> + int ret, i, wol_irq, count = 0;
> + struct bcmasp_intf *intf;
> + struct resource *r;
> + u32 u32_reserved_filters_bitmask;
> + DECLARE_BITMAP(reserved_filters_bitmask, ASP_RX_NET_FILTER_MAX);
> +
> + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> + if (!priv)
> + return -ENOMEM;
> +
> + priv->irq = platform_get_irq(pdev, 0);
> + if (priv->irq <= 0) {
> + dev_err(dev, "invalid interrupt\n");
> + return -EINVAL;
> + }
> +
> + priv->clk = devm_clk_get(dev, "sw_asp");
> + if (IS_ERR(priv->clk)) {
> + if (PTR_ERR(priv->clk) == -EPROBE_DEFER)
> + return -EPROBE_DEFER;
> + dev_warn(dev, "failed to request clock\n");
> + priv->clk = NULL;
> + }

devm_clk_get_optional() makes this simpler/

> +
> + /* Base from parent node */
> + r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> + priv->base = devm_ioremap_resource(&pdev->dev, r);
> + if (IS_ERR(priv->base)) {
> + dev_err(dev, "failed to iomap\n");
> + return PTR_ERR(priv->base);
> + }
> +
> + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(40));
> + if (ret)
> + ret = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
> + if (ret) {
> + dev_err(&pdev->dev, "unable to set DMA mask: %d\n", ret);
> + return ret;
> + }
> +
> + dev_set_drvdata(&pdev->dev, priv);
> + priv->pdev = pdev;
> + spin_lock_init(&priv->mda_lock);
> + spin_lock_init(&priv->clk_lock);
> + mutex_init(&priv->net_lock);
> +
> + ret = clk_prepare_enable(priv->clk);
> + if (ret)
> + return ret;
> +
> + /* Enable all clocks to ensure successful probing */
> + bcmasp_core_clock_set(priv, ASP_CTRL_CLOCK_CTRL_ASP_ALL_DISABLE, 0);
> +
> + /* Switch to the main clock */
> + bcmasp_core_clock_select(priv, false);
> +
> + _intr2_mask_set(priv, 0xffffffff);
> + intr2_core_wl(priv, 0xffffffff, ASP_INTR2_CLEAR);
> +
> + ret = devm_request_irq(&pdev->dev, priv->irq, bcmasp_isr, 0,
> + pdev->name, priv);
> + if (ret) {
> + dev_err(dev, "failed to request ASP interrupt: %d\n", ret);
> + return ret;
> + }

Do you need to undo clk_prepare_enable()?

> +
> + /* Register mdio child nodes */
> + of_platform_populate(dev->of_node, bcmasp_mdio_of_match, NULL,
> + dev);
> +
> + ret = of_property_read_u32(dev->of_node,
> + "brcm,reserved-net-filters-mask",
> + &u32_reserved_filters_bitmask);
> + if (ret)
> + u32_reserved_filters_bitmask = 0;
> +
> + priv->net_filters_count_max = ASP_RX_NET_FILTER_MAX;
> + bitmap_zero(reserved_filters_bitmask, priv->net_filters_count_max);
> + bitmap_from_arr32(reserved_filters_bitmask,
> + &u32_reserved_filters_bitmask,
> + priv->net_filters_count_max);
> +
> + /* Discover bitmask of reserved filters */
> + for_each_set_bit(i, reserved_filters_bitmask, ASP_RX_NET_FILTER_MAX) {
> + priv->net_filters[i].reserved = true;
> + priv->net_filters_count_max--;
> + }
> +
> + /*
> + * ASP specific initialization, Needs to be done irregardless of
> + * of how many interfaces come up.
> + */
> + bcmasp_core_init(priv);
> + bcmasp_core_init_filters(priv);
> +
> + ports_node = of_find_node_by_name(dev->of_node, "ethernet-ports");
> + if (!ports_node) {
> + dev_warn(dev, "No ports found\n");
> + return 0;
> + }
> +
> + priv->intf_count = of_get_available_child_count(ports_node);
> +
> + priv->intfs = devm_kcalloc(dev, priv->intf_count,
> + sizeof(struct bcmasp_intf *),
> + GFP_KERNEL);
> + if (!priv->intfs)
> + return -ENOMEM;
> +
> + /* Probe each interface (Initalization should continue even if
> + * interfaces are unable to come up)
> + */
> + i = 0;
> + for_each_available_child_of_node(ports_node, intf_node) {
> + wol_irq = platform_get_irq_optional(pdev, i + 1);
> + priv->intfs[i++] = bcmasp_interface_create(priv, intf_node,
> + wol_irq);
> + }
> +
> + /* Drop the clock reference count now and let ndo_open()/ndo_close()
> + * manage it for us from now on.
> + */
> + bcmasp_core_clock_set(priv, 0, ASP_CTRL_CLOCK_CTRL_ASP_ALL_DISABLE);
> +
> + clk_disable_unprepare(priv->clk);
> +
> + /* Now do the registration of the network ports which will take care of
> + * managing the clock properly.
> + */
> + for (i = 0; i < priv->intf_count; i++) {
> + intf = priv->intfs[i];
> + if (!intf)
> + continue;
> +
> + ret = register_netdev(intf->ndev);
> + if (ret) {
> + netdev_err(intf->ndev,
> + "failed to register net_device: %d\n", ret);
> + bcmasp_interface_destroy(intf, false);
> + continue;
> + }
> + count++;
> + }
> +
> + dev_info(dev, "Initialized %d port(s)\n", count);
> +
> + return 0;
> +}
> +
> +static int bcmasp_remove(struct platform_device *pdev)
> +{
> + struct bcmasp_priv *priv = dev_get_drvdata(&pdev->dev);
> + struct bcmasp_intf *intf;
> + int i;
> +
> + for (i = 0; i < priv->intf_count; i++) {
> + intf = priv->intfs[i];
> + if (!intf)
> + continue;
> +
> + bcmasp_interface_destroy(intf, true);
> + }
> +
> + return 0;
> +}

Do you need to depopulate the mdio children?

> +static void bcmasp_get_drvinfo(struct net_device *dev,
> + struct ethtool_drvinfo *info)
> +{
> + strlcpy(info->driver, "bcmasp", sizeof(info->driver));
> + strlcpy(info->version, "v2.0", sizeof(info->version));

Please drop version. The core will fill it in with the kernel version,
which is more useful.

> +static int bcmasp_nway_reset(struct net_device *dev)
> +{
> + if (!dev->phydev)
> + return -ENODEV;
> +
> + return genphy_restart_aneg(dev->phydev);
> +}

phy_ethtool_nway_reset().


> +static void bcmasp_get_wol(struct net_device *dev, struct ethtool_wolinfo *wol)
> +{
> + struct bcmasp_intf *intf = netdev_priv(dev);
> +
> + wol->supported = WAKE_MAGIC | WAKE_MAGICSECURE | WAKE_FILTER;
> + wol->wolopts = intf->wolopts;
> + memset(wol->sopass, 0, sizeof(wol->sopass));
> +
> + if (wol->wolopts & WAKE_MAGICSECURE)
> + memcpy(wol->sopass, intf->sopass, sizeof(intf->sopass));
> +}

Maybe consider calling into the PHY to see what it can do? If the PHY
can do the WoL you want, it will do it with less power.

> +static int bcmasp_set_priv_flags(struct net_device *dev, u32 flags)
> +{
> + struct bcmasp_intf *intf = netdev_priv(dev);
> +
> + intf->wol_keep_rx_en = flags & BCMASP_WOL_KEEP_RX_EN ? 1 : 0;
> +
> + return 0;

Please could you explain this some more. How can you disable RX and
still have WoL working?

> +static void bcmasp_adj_link(struct net_device *dev)
> +{
> + struct bcmasp_intf *intf = netdev_priv(dev);
> + struct phy_device *phydev = dev->phydev;
> + int changed = 0;
> + u32 cmd_bits = 0, reg;
> +
> + if (intf->old_link != phydev->link) {
> + changed = 1;
> + intf->old_link = phydev->link;
> + }
> +
> + if (intf->old_duplex != phydev->duplex) {
> + changed = 1;
> + intf->old_duplex = phydev->duplex;
> + }
> +
> + switch (phydev->speed) {
> + case SPEED_2500:
> + cmd_bits = UMC_CMD_SPEED_2500;

All i've seen is references to RGMII. Is 2500 possible?

> + break;
> + case SPEED_1000:
> + cmd_bits = UMC_CMD_SPEED_1000;
> + break;
> + case SPEED_100:
> + cmd_bits = UMC_CMD_SPEED_100;
> + break;
> + case SPEED_10:
> + cmd_bits = UMC_CMD_SPEED_10;
> + break;
> + default:
> + break;
> + }
> + cmd_bits <<= UMC_CMD_SPEED_SHIFT;
> +
> + if (phydev->duplex == DUPLEX_HALF)
> + cmd_bits |= UMC_CMD_HD_EN;
> +
> + if (intf->old_pause != phydev->pause) {
> + changed = 1;
> + intf->old_pause = phydev->pause;
> + }
> +
> + if (!phydev->pause)
> + cmd_bits |= UMC_CMD_RX_PAUSE_IGNORE | UMC_CMD_TX_PAUSE_IGNORE;
> +
> + if (!changed)
> + return;

Shouldn't there be a comparison intd->old_speed != phydev->speed? You
are risking the PHY can change speed without doing a link down/up?

> +
> + if (phydev->link) {
> + reg = umac_rl(intf, UMC_CMD);
> + reg &= ~((UMC_CMD_SPEED_MASK << UMC_CMD_SPEED_SHIFT) |
> + UMC_CMD_HD_EN | UMC_CMD_RX_PAUSE_IGNORE |
> + UMC_CMD_TX_PAUSE_IGNORE);
> + reg |= cmd_bits;
> + umac_wl(intf, reg, UMC_CMD);
> +
> + /* Enable RGMII pad */
> + reg = rgmii_rl(intf, RGMII_OOB_CNTRL);
> + reg |= RGMII_MODE_EN;
> + rgmii_wl(intf, reg, RGMII_OOB_CNTRL);
> +
> + intf->eee.eee_active = phy_init_eee(phydev, 0) >= 0;
> + bcmasp_eee_enable_set(intf, intf->eee.eee_active);
> + } else {
> + /* Disable RGMII pad */
> + reg = rgmii_rl(intf, RGMII_OOB_CNTRL);
> + reg &= ~RGMII_MODE_EN;
> + rgmii_wl(intf, reg, RGMII_OOB_CNTRL);
> + }
> +
> + if (changed)
> + phy_print_status(phydev);

There has already been a return if !changed.

> +static void bcmasp_configure_port(struct bcmasp_intf *intf)
> +{
> + u32 reg, id_mode_dis = 0;
> +
> + reg = rgmii_rl(intf, RGMII_PORT_CNTRL);
> + reg &= ~RGMII_PORT_MODE_MASK;
> +
> + switch (intf->phy_interface) {
> + case PHY_INTERFACE_MODE_RGMII:
> + /* RGMII_NO_ID: TXC transitions at the same time as TXD
> + * (requires PCB or receiver-side delay)
> + * RGMII: Add 2ns delay on TXC (90 degree shift)
> + *
> + * ID is implicitly disabled for 100Mbps (RG)MII operation.
> + */
> + id_mode_dis = RGMII_ID_MODE_DIS;
> + fallthrough;
> + case PHY_INTERFACE_MODE_RGMII_TXID:
> + reg |= RGMII_PORT_MODE_EXT_GPHY;
> + break;
> + case PHY_INTERFACE_MODE_MII:
> + reg |= RGMII_PORT_MODE_EXT_EPHY;
> + break;
> + default:
> + break;
> + }

Can we skip this and let the PHY do the delays? Ah, "This is an ugly
quirk..." Maybe add a comment here pointing towards
bcmasp_netif_init(), which is explains this.

> +static int bcmasp_netif_init(struct net_device *dev, bool phy_connect,
> + bool init_rx)
> +{
> + struct bcmasp_intf *intf = netdev_priv(dev);
> + phy_interface_t phy_iface = intf->phy_interface;
> + u32 phy_flags = PHY_BRCM_AUTO_PWRDWN_ENABLE |
> + PHY_BRCM_DIS_TXCRXC_NOENRGY |
> + PHY_BRCM_IDDQ_SUSPEND;
> + struct phy_device *phydev = NULL;
> + int ret;
> +
> + /* Always enable interface clocks */
> + bcmasp_core_clock_set_intf(intf, true);
> +
> + /* Enable internal PHY before any MAC activity */
> + if (intf->internal_phy)
> + bcmasp_ephy_enable_set(intf, true);
> +
> + bcmasp_configure_port(intf);
> +
> + /* This is an ugly quirk but we have not been correctly interpreting
> + * the phy_interface values and we have done that across different
> + * drivers, so at least we are consistent in our mistakes.
> + *
> + * When the Generic PHY driver is in use either the PHY has been
> + * strapped or programmed correctly by the boot loader so we should
> + * stick to our incorrect interpretation since we have validated it.
> + *
> + * Now when a dedicated PHY driver is in use, we need to reverse the
> + * meaning of the phy_interface_mode values to something that the PHY
> + * driver will interpret and act on such that we have two mistakes
> + * canceling themselves so to speak. We only do this for the two
> + * modes that GENET driver officially supports on Broadcom STB chips:
> + * PHY_INTERFACE_MODE_RGMII and PHY_INTERFACE_MODE_RGMII_TXID. Other
> + * modes are not *officially* supported with the boot loader and the
> + * scripted environment generating Device Tree blobs for those
> + * platforms.
> + *
> + * Note that internal PHY and fixed-link configurations are not
> + * affected because they use different phy_interface_t values or the
> + * Generic PHY driver.
> + */


> +static inline void bcmasp_map_res(struct bcmasp_priv *priv,
> + struct bcmasp_intf *intf)
> +{
> + /* Per port */
> + intf->res.umac = priv->base + UMC_OFFSET(intf);
> + intf->res.umac2fb = priv->base + UMAC2FB_OFFSET(intf);
> + intf->res.rgmii = priv->base + RGMII_OFFSET(intf);
> +
> + /* Per ch */
> + intf->tx_spb_dma = priv->base + TX_SPB_DMA_OFFSET(intf);
> + intf->res.tx_spb_ctrl = priv->base + TX_SPB_CTRL_OFFSET(intf);
> + /*
> + * Stop gap solution. This should be removed when 72165a0 is
> + * deprecated
> + */

Is that an internal commit?

Andrew