This patch implements accessors for the QCA8337 MDIO access through the MDIO_MASTER register, which makes it possible to access the PHYs on slave-bus through the switch. In cases where the switch ports are already mapped via external "phy-phandles", the internal mdio-bus is disabled in order to prevent a duplicated discovery and enumeration of the same PHYs. Don't use mixed external and internal mdio-bus configurations, as this is not supported by the hardware. Signed-off-by: Christian Lamparter <chunkeey@xxxxxxxxx> --- Changes from v3: - removed unneccessary PHYAD checks - let dsa subsystem setup the slave bus, but only if needed - saved an indent level in qca8k_setup_mdio_bus() - Reverse XMAS tree-ized Changes from v2: - Make it compatible with existing configurations - make it clear that's sadly a either external or internal mdio bus access. Changes from v1: - drop DT port <-> phy mapping - added register definitions for the MDIO control register - implemented new slave-mdio bus accessors - DT-binding: fix switch's PSEUDO_PHY address. It's 0x10 not 0. Old patch (+ discussion) for reference: <https://patchwork.ozlabs.org/patch/1036309/> Tested on a Compex WPQ864 (IPQ8064 + QCA8337N) internal bus: qca8k 37000000.mdio-mii:10 lan1 (uninitialized): PHY [dsa-0.0:01] driver [Generic PHY] qca8k 37000000.mdio-mii:10 lan2 (uninitialized): PHY [dsa-0.0:02] driver [Generic PHY] qca8k 37000000.mdio-mii:10 lan3 (uninitialized): PHY [dsa-0.0:03] driver [Generic PHY] qca8k 37000000.mdio-mii:10 lan4 (uninitialized): PHY [dsa-0.0:04] driver [Generic PHY] qca8k 37000000.mdio-mii:10 wan (uninitialized): PHY [dsa-0.0:05] driver [Generic PHY] external bus: qca8k 37000000.mdio-mii:10 lan1 (uninitialized): PHY [37000000.mdio-mii:00] driver [Generic PHY] qca8k 37000000.mdio-mii:10 lan2 (uninitialized): PHY [37000000.mdio-mii:01] driver [Generic PHY] qca8k 37000000.mdio-mii:10 lan3 (uninitialized): PHY [37000000.mdio-mii:02] driver [Generic PHY] qca8k 37000000.mdio-mii:10 lan4 (uninitialized): PHY [37000000.mdio-mii:03] driver [Generic PHY] qca8k 37000000.mdio-mii:10 wan (uninitialized): PHY [37000000.mdio-mii:04] driver [Generic PHY] --- drivers/net/dsa/qca8k.c | 156 +++++++++++++++++++++++++++++++++++++++- drivers/net/dsa/qca8k.h | 13 ++++ 2 files changed, 168 insertions(+), 1 deletion(-) diff --git a/drivers/net/dsa/qca8k.c b/drivers/net/dsa/qca8k.c index 14ad78225f07..c4fa400efdcc 100644 --- a/drivers/net/dsa/qca8k.c +++ b/drivers/net/dsa/qca8k.c @@ -481,6 +481,155 @@ qca8k_port_set_status(struct qca8k_priv *priv, int port, int enable) qca8k_reg_clear(priv, QCA8K_REG_PORT_STATUS(port), mask); } +static u32 +qca8k_port_to_phy(int port) +{ + /* From Andrew Lunn: + * Port 0 has no internal phy. + * Port 1 has an internal PHY at MDIO address 0. + * Port 2 has an internal PHY at MDIO address 1. + * ... + * Port 5 has an internal PHY at MDIO address 4. + * Port 6 has no internal PHY. + */ + + return port - 1; +} + +static int +qca8k_mdio_write(struct qca8k_priv *priv, int port, u32 regnum, u16 data) +{ + u32 phy, val; + + if (regnum >= QCA8K_MDIO_MASTER_MAX_REG) + return -EINVAL; + + /* callee is responsible for not passing bad ports, + * but we still would like to make spills impossible. + */ + phy = qca8k_port_to_phy(port) % PHY_MAX_ADDR; + val = QCA8K_MDIO_MASTER_BUSY | QCA8K_MDIO_MASTER_EN | + QCA8K_MDIO_MASTER_WRITE | QCA8K_MDIO_MASTER_PHY_ADDR(phy) | + QCA8K_MDIO_MASTER_REG_ADDR(regnum) | + QCA8K_MDIO_MASTER_DATA(data); + + qca8k_write(priv, QCA8K_MDIO_MASTER_CTRL, val); + + return qca8k_busy_wait(priv, QCA8K_MDIO_MASTER_CTRL, + QCA8K_MDIO_MASTER_BUSY); +} + +static int +qca8k_mdio_read(struct qca8k_priv *priv, int port, u32 regnum) +{ + u32 phy, val; + + if (regnum >= QCA8K_MDIO_MASTER_MAX_REG) + return -EINVAL; + + /* callee is responsible for not passing bad ports, + * but we still would like to make spills impossible. + */ + phy = qca8k_port_to_phy(port) % PHY_MAX_ADDR; + val = QCA8K_MDIO_MASTER_BUSY | QCA8K_MDIO_MASTER_EN | + QCA8K_MDIO_MASTER_READ | QCA8K_MDIO_MASTER_PHY_ADDR(phy) | + QCA8K_MDIO_MASTER_REG_ADDR(regnum); + + qca8k_write(priv, QCA8K_MDIO_MASTER_CTRL, val); + + if (qca8k_busy_wait(priv, QCA8K_MDIO_MASTER_CTRL, + QCA8K_MDIO_MASTER_BUSY)) + return -ETIMEDOUT; + + val = (qca8k_read(priv, QCA8K_MDIO_MASTER_CTRL) & + QCA8K_MDIO_MASTER_DATA_MASK); + + return val; +} + +static int +qca8k_phy_write(struct dsa_switch *ds, int port, int regnum, u16 data) +{ + struct qca8k_priv *priv = ds->priv; + + return qca8k_mdio_write(priv, port, regnum, data); +} + +static int +qca8k_phy_read(struct dsa_switch *ds, int port, int regnum) +{ + struct qca8k_priv *priv = ds->priv; + int ret; + + ret = qca8k_mdio_read(priv, port, regnum); + + if (ret < 0) + return 0xffff; + + return ret; +} + +static int +qca8k_setup_mdio_bus(struct qca8k_priv *priv) +{ + u32 internal_mdio_mask = 0, external_mdio_mask = 0, reg; + struct device_node *ports, *port; + int err; + + ports = of_get_child_by_name(priv->dev->of_node, "ports"); + if (!ports) + return -EINVAL; + + for_each_available_child_of_node(ports, port) { + err = of_property_read_u32(port, "reg", ®); + if (err) + return err; + + if (!dsa_is_user_port(priv->ds, reg)) + continue; + + if (of_property_read_bool(port, "phy-handle")) + external_mdio_mask |= BIT(reg); + else + internal_mdio_mask |= BIT(reg); + } + + if (!external_mdio_mask && !internal_mdio_mask) { + dev_err(priv->dev, "no PHYs are defined.\n"); + return -EINVAL; + } + + /* The QCA8K_MDIO_MASTER_EN Bit, which grants access to PHYs through + * the MDIO_MASTER register also _disconnects_ the external MDC + * passthrough to the internal PHYs. It's not possible to use both + * configurations at the same time! + * + * Because this came up during the review process: + * If the external mdio-bus driver is capable magically disabling + * the QCA8K_MDIO_MASTER_EN and mutex/spin-locking out the qca8k's + * accessors for the time being, it would be possible to pull this + * off. + */ + if (!!external_mdio_mask && !!internal_mdio_mask) { + dev_err(priv->dev, "either internal or external mdio bus configuration is supported.\n"); + return -EINVAL; + } + + if (external_mdio_mask) { + /* Make sure to disable the internal mdio bus in cases + * a dt-overlay and driver reload changed the configuration + */ + + qca8k_reg_clear(priv, QCA8K_MDIO_MASTER_CTRL, + QCA8K_MDIO_MASTER_EN); + return 0; + } + + priv->ops.phy_read = qca8k_phy_read; + priv->ops.phy_write = qca8k_phy_write; + return 0; +} + static int qca8k_setup(struct dsa_switch *ds) { @@ -502,6 +651,10 @@ qca8k_setup(struct dsa_switch *ds) if (IS_ERR(priv->regmap)) pr_warn("regmap initialization failed"); + ret = qca8k_setup_mdio_bus(priv); + if (ret) + return ret; + /* Initialize CPU port pad mode (xMII type, delays...) */ phy_mode = of_get_phy_mode(ds->ports[QCA8K_CPU_PORT].dn); if (phy_mode < 0) { @@ -905,7 +1058,8 @@ qca8k_sw_probe(struct mdio_device *mdiodev) return -ENOMEM; priv->ds->priv = priv; - priv->ds->ops = &qca8k_switch_ops; + priv->ops = qca8k_switch_ops; + priv->ds->ops = &priv->ops; mutex_init(&priv->reg_mutex); dev_set_drvdata(&mdiodev->dev, priv); diff --git a/drivers/net/dsa/qca8k.h b/drivers/net/dsa/qca8k.h index d146e54c8a6c..249fd62268e5 100644 --- a/drivers/net/dsa/qca8k.h +++ b/drivers/net/dsa/qca8k.h @@ -49,6 +49,18 @@ #define QCA8K_MIB_FLUSH BIT(24) #define QCA8K_MIB_CPU_KEEP BIT(20) #define QCA8K_MIB_BUSY BIT(17) +#define QCA8K_MDIO_MASTER_CTRL 0x3c +#define QCA8K_MDIO_MASTER_BUSY BIT(31) +#define QCA8K_MDIO_MASTER_EN BIT(30) +#define QCA8K_MDIO_MASTER_READ BIT(27) +#define QCA8K_MDIO_MASTER_WRITE 0 +#define QCA8K_MDIO_MASTER_SUP_PRE BIT(26) +#define QCA8K_MDIO_MASTER_PHY_ADDR(x) ((x) << 21) +#define QCA8K_MDIO_MASTER_REG_ADDR(x) ((x) << 16) +#define QCA8K_MDIO_MASTER_DATA(x) (x) +#define QCA8K_MDIO_MASTER_DATA_MASK GENMASK(15, 0) +#define QCA8K_MDIO_MASTER_MAX_PORTS 5 +#define QCA8K_MDIO_MASTER_MAX_REG 32 #define QCA8K_GOL_MAC_ADDR0 0x60 #define QCA8K_GOL_MAC_ADDR1 0x64 #define QCA8K_REG_PORT_STATUS(_i) (0x07c + (_i) * 4) @@ -169,6 +181,7 @@ struct qca8k_priv { struct dsa_switch *ds; struct mutex reg_mutex; struct device *dev; + struct dsa_switch_ops ops; }; struct qca8k_mib_desc { -- 2.20.1
