[PATCH net-next 2/2] net: altera: tse: convert to phylink

From: Maxime Chevallier
Date: Tue Aug 23 2022 - 13:07:38 EST

This commit converts the Altera Triple Speed Ethernet Controller to
phylink. This controller supports MII, GMII and RGMII with its MAC, and
SGMII + 1000BaseX through a small embedded PCS.

The PCS itself has a register set very similar to what is found in a
typical 802.3 ethernet PHY, but this register set memory-mapped instead
of lying on an mdio bus.

Signed-off-by: Maxime Chevallier <maxime.chevallier@xxxxxxxxxxx>
---
drivers/net/ethernet/altera/Kconfig | 1 +
drivers/net/ethernet/altera/altera_tse.h | 13 +
.../net/ethernet/altera/altera_tse_ethtool.c | 20 +-
drivers/net/ethernet/altera/altera_tse_main.c | 407 ++++++------------
4 files changed, 166 insertions(+), 275 deletions(-)

diff --git a/drivers/net/ethernet/altera/Kconfig b/drivers/net/ethernet/altera/Kconfig
index 914e56b91467..d6e02b3bcd76 100644
--- a/drivers/net/ethernet/altera/Kconfig
+++ b/drivers/net/ethernet/altera/Kconfig
@@ -3,6 +3,7 @@ config ALTERA_TSE
tristate "Altera Triple-Speed Ethernet MAC support"
depends on HAS_DMA
select PHYLIB
+ select PHYLINK
help
This driver supports the Altera Triple-Speed (TSE) Ethernet MAC.

diff --git a/drivers/net/ethernet/altera/altera_tse.h b/drivers/net/ethernet/altera/altera_tse.h
index f17acfb579a0..2309f1785370 100644
--- a/drivers/net/ethernet/altera/altera_tse.h
+++ b/drivers/net/ethernet/altera/altera_tse.h
@@ -27,6 +27,7 @@
#include <linux/list.h>
#include <linux/netdevice.h>
#include <linux/phy.h>
+#include <linux/phylink.h>

#define ALTERA_TSE_SW_RESET_WATCHDOG_CNTR 10000
#define ALTERA_TSE_MAC_FIFO_WIDTH 4 /* TX/RX FIFO width in
@@ -114,8 +115,17 @@
#define SGMII_PCS_SCRATCH 0x10
#define SGMII_PCS_REV 0x11
#define SGMII_PCS_LINK_TIMER_0 0x12
+#define SGMII_PCS_LINK_TIMER_REG(x) (0x12 + (x))
#define SGMII_PCS_LINK_TIMER_1 0x13
#define SGMII_PCS_IF_MODE 0x14
+#define PCS_IF_MODE_SGMII_ENA BIT(0)
+#define PCS_IF_MODE_USE_SGMII_AN BIT(1)
+#define PCS_IF_MODE_SGMI_SPEED_MASK GENMASK(3, 2)
+#define PCS_IF_MODE_SGMI_SPEED_10 (0 << 2)
+#define PCS_IF_MODE_SGMI_SPEED_100 (1 << 2)
+#define PCS_IF_MODE_SGMI_SPEED_1000 (2 << 2)
+#define PCS_IF_MODE_SGMI_HALF_DUPLEX BIT(4)
+#define PCS_IF_MODE_SGMI_PHY_AN BIT(5)
#define SGMII_PCS_DIS_READ_TO 0x15
#define SGMII_PCS_READ_TO 0x16
#define SGMII_PCS_SW_RESET_TIMEOUT 100 /* usecs */
@@ -480,6 +490,9 @@ struct altera_tse_private {
u32 msg_enable;

struct altera_dmaops *dmaops;
+
+ struct phylink *phylink;
+ struct phylink_config phylink_config;
};

/* Function prototypes
diff --git a/drivers/net/ethernet/altera/altera_tse_ethtool.c b/drivers/net/ethernet/altera/altera_tse_ethtool.c
index 3081e5874ac5..034a4cb3c1ab 100644
--- a/drivers/net/ethernet/altera/altera_tse_ethtool.c
+++ b/drivers/net/ethernet/altera/altera_tse_ethtool.c
@@ -221,6 +221,22 @@ static void tse_get_regs(struct net_device *dev, struct ethtool_regs *regs,
buf[i] = csrrd32(priv->mac_dev, i * 4);
}

+static int tse_ethtool_set_link_ksettings(struct net_device *dev,
+ const struct ethtool_link_ksettings *cmd)
+{
+ struct altera_tse_private *priv = netdev_priv(dev);
+
+ return phylink_ethtool_ksettings_set(priv->phylink, cmd);
+}
+
+static int tse_ethtool_get_link_ksettings(struct net_device *dev,
+ struct ethtool_link_ksettings *cmd)
+{
+ struct altera_tse_private *priv = netdev_priv(dev);
+
+ return phylink_ethtool_ksettings_get(priv->phylink, cmd);
+}
+
static const struct ethtool_ops tse_ethtool_ops = {
.get_drvinfo = tse_get_drvinfo,
.get_regs_len = tse_reglen,
@@ -231,8 +247,8 @@ static const struct ethtool_ops tse_ethtool_ops = {
.get_ethtool_stats = tse_fill_stats,
.get_msglevel = tse_get_msglevel,
.set_msglevel = tse_set_msglevel,
- .get_link_ksettings = phy_ethtool_get_link_ksettings,
- .set_link_ksettings = phy_ethtool_set_link_ksettings,
+ .get_link_ksettings = tse_ethtool_get_link_ksettings,
+ .set_link_ksettings = tse_ethtool_set_link_ksettings,
.get_ts_info = ethtool_op_get_ts_info,
};

diff --git a/drivers/net/ethernet/altera/altera_tse_main.c b/drivers/net/ethernet/altera/altera_tse_main.c
index ad59b0befc18..9bc1907dbd6c 100644
--- a/drivers/net/ethernet/altera/altera_tse_main.c
+++ b/drivers/net/ethernet/altera/altera_tse_main.c
@@ -100,13 +100,6 @@ static void sgmii_pcs_write(struct altera_tse_private *priv, int regnum,
csrwr32(value, priv->mac_dev, tse_csroffs(mdio_phy0) + regnum * 4);
}

-/* Check PCS scratch memory */
-static int sgmii_pcs_scratch_test(struct altera_tse_private *priv, u16 value)
-{
- sgmii_pcs_write(priv, SGMII_PCS_SCRATCH, value);
- return (sgmii_pcs_read(priv, SGMII_PCS_SCRATCH) == value);
-}
-
static int sgmii_pcs_reset(struct altera_tse_private *priv)
{
u16 bmcr;
@@ -638,117 +631,6 @@ static netdev_tx_t tse_start_xmit(struct sk_buff *skb, struct net_device *dev)
return ret;
}

-/* Called every time the controller might need to be made
- * aware of new link state. The PHY code conveys this
- * information through variables in the phydev structure, and this
- * function converts those variables into the appropriate
- * register values, and can bring down the device if needed.
- */
-static void altera_tse_adjust_link(struct net_device *dev)
-{
- struct altera_tse_private *priv = netdev_priv(dev);
- struct phy_device *phydev = dev->phydev;
- int new_state = 0;
-
- /* only change config if there is a link */
- spin_lock(&priv->mac_cfg_lock);
- if (phydev->link) {
- /* Read old config */
- u32 cfg_reg = ioread32(&priv->mac_dev->command_config);
-
- /* Check duplex */
- if (phydev->duplex != priv->oldduplex) {
- new_state = 1;
- if (!(phydev->duplex))
- cfg_reg |= MAC_CMDCFG_HD_ENA;
- else
- cfg_reg &= ~MAC_CMDCFG_HD_ENA;
-
- netdev_dbg(priv->dev, "%s: Link duplex = 0x%x\n",
- dev->name, phydev->duplex);
-
- priv->oldduplex = phydev->duplex;
- }
-
- /* Check speed */
- if (phydev->speed != priv->oldspeed) {
- new_state = 1;
- switch (phydev->speed) {
- case 1000:
- cfg_reg |= MAC_CMDCFG_ETH_SPEED;
- cfg_reg &= ~MAC_CMDCFG_ENA_10;
- break;
- case 100:
- cfg_reg &= ~MAC_CMDCFG_ETH_SPEED;
- cfg_reg &= ~MAC_CMDCFG_ENA_10;
- break;
- case 10:
- cfg_reg &= ~MAC_CMDCFG_ETH_SPEED;
- cfg_reg |= MAC_CMDCFG_ENA_10;
- break;
- default:
- if (netif_msg_link(priv))
- netdev_warn(dev, "Speed (%d) is not 10/100/1000!\n",
- phydev->speed);
- break;
- }
- priv->oldspeed = phydev->speed;
- }
- iowrite32(cfg_reg, &priv->mac_dev->command_config);
-
- if (!priv->oldlink) {
- new_state = 1;
- priv->oldlink = 1;
- }
- } else if (priv->oldlink) {
- new_state = 1;
- priv->oldlink = 0;
- priv->oldspeed = 0;
- priv->oldduplex = -1;
- }
-
- if (new_state && netif_msg_link(priv))
- phy_print_status(phydev);
-
- spin_unlock(&priv->mac_cfg_lock);
-}
-static struct phy_device *connect_local_phy(struct net_device *dev)
-{
- struct altera_tse_private *priv = netdev_priv(dev);
- struct phy_device *phydev = NULL;
- char phy_id_fmt[MII_BUS_ID_SIZE + 3];
-
- if (priv->phy_addr != POLL_PHY) {
- snprintf(phy_id_fmt, MII_BUS_ID_SIZE + 3, PHY_ID_FMT,
- priv->mdio->id, priv->phy_addr);
-
- netdev_dbg(dev, "trying to attach to %s\n", phy_id_fmt);
-
- phydev = phy_connect(dev, phy_id_fmt, &altera_tse_adjust_link,
- priv->phy_iface);
- if (IS_ERR(phydev)) {
- netdev_err(dev, "Could not attach to PHY\n");
- phydev = NULL;
- }
-
- } else {
- int ret;
- phydev = phy_find_first(priv->mdio);
- if (phydev == NULL) {
- netdev_err(dev, "No PHY found\n");
- return phydev;
- }
-
- ret = phy_connect_direct(dev, phydev, &altera_tse_adjust_link,
- priv->phy_iface);
- if (ret != 0) {
- netdev_err(dev, "Could not attach to PHY\n");
- phydev = NULL;
- }
- }
- return phydev;
-}
-
static int altera_tse_phy_get_addr_mdio_create(struct net_device *dev)
{
struct altera_tse_private *priv = netdev_priv(dev);
@@ -787,91 +669,6 @@ static int altera_tse_phy_get_addr_mdio_create(struct net_device *dev)
return 0;
}

-/* Initialize driver's PHY state, and attach to the PHY
- */
-static int init_phy(struct net_device *dev)
-{
- struct altera_tse_private *priv = netdev_priv(dev);
- struct phy_device *phydev;
- struct device_node *phynode;
- bool fixed_link = false;
- int rc = 0;
-
- /* Avoid init phy in case of no phy present */
- if (!priv->phy_iface)
- return 0;
-
- priv->oldlink = 0;
- priv->oldspeed = 0;
- priv->oldduplex = -1;
-
- phynode = of_parse_phandle(priv->device->of_node, "phy-handle", 0);
-
- if (!phynode) {
- /* check if a fixed-link is defined in device-tree */
- if (of_phy_is_fixed_link(priv->device->of_node)) {
- rc = of_phy_register_fixed_link(priv->device->of_node);
- if (rc < 0) {
- netdev_err(dev, "cannot register fixed PHY\n");
- return rc;
- }
-
- /* In the case of a fixed PHY, the DT node associated
- * to the PHY is the Ethernet MAC DT node.
- */
- phynode = of_node_get(priv->device->of_node);
- fixed_link = true;
-
- netdev_dbg(dev, "fixed-link detected\n");
- phydev = of_phy_connect(dev, phynode,
- &altera_tse_adjust_link,
- 0, priv->phy_iface);
- } else {
- netdev_dbg(dev, "no phy-handle found\n");
- if (!priv->mdio) {
- netdev_err(dev, "No phy-handle nor local mdio specified\n");
- return -ENODEV;
- }
- phydev = connect_local_phy(dev);
- }
- } else {
- netdev_dbg(dev, "phy-handle found\n");
- phydev = of_phy_connect(dev, phynode,
- &altera_tse_adjust_link, 0, priv->phy_iface);
- }
- of_node_put(phynode);
-
- if (!phydev) {
- netdev_err(dev, "Could not find the PHY\n");
- if (fixed_link)
- of_phy_deregister_fixed_link(priv->device->of_node);
- return -ENODEV;
- }
-
- /* Stop Advertising 1000BASE Capability if interface is not GMII
- */
- if ((priv->phy_iface == PHY_INTERFACE_MODE_MII) ||
- (priv->phy_iface == PHY_INTERFACE_MODE_RMII))
- phy_set_max_speed(phydev, SPEED_100);
-
- /* Broken HW is sometimes missing the pull-up resistor on the
- * MDIO line, which results in reads to non-existent devices returning
- * 0 rather than 0xffff. Catch this here and treat 0 as a non-existent
- * device as well. If a fixed-link is used the phy_id is always 0.
- * Note: phydev->phy_id is the result of reading the UID PHY registers.
- */
- if ((phydev->phy_id == 0) && !fixed_link) {
- netdev_err(dev, "Bad PHY UID 0x%08x\n", phydev->phy_id);
- phy_disconnect(phydev);
- return -ENODEV;
- }
-
- netdev_dbg(dev, "attached to PHY %d UID 0x%08x Link = %d\n",
- phydev->mdio.addr, phydev->phy_id, phydev->link);
-
- return 0;
-}
-
static void tse_update_mac_addr(struct altera_tse_private *priv, const u8 *addr)
{
u32 msb;
@@ -1106,52 +903,6 @@ static void tse_set_rx_mode(struct net_device *dev)
spin_unlock(&priv->mac_cfg_lock);
}

-/* Initialise (if necessary) the SGMII PCS component
- */
-static int init_sgmii_pcs(struct net_device *dev)
-{
- struct altera_tse_private *priv = netdev_priv(dev);
- unsigned int tmp_reg = 0;
-
- if (priv->phy_iface != PHY_INTERFACE_MODE_SGMII)
- return 0; /* Nothing to do, not in SGMII mode */
-
- /* The TSE SGMII PCS block looks a little like a PHY, it is
- * mapped into the zeroth MDIO space of the MAC and it has
- * ID registers like a PHY would. Sadly this is often
- * configured to zeroes, so don't be surprised if it does
- * show 0x00000000.
- */
-
- if (sgmii_pcs_scratch_test(priv, 0x0000) &&
- sgmii_pcs_scratch_test(priv, 0xffff) &&
- sgmii_pcs_scratch_test(priv, 0xa5a5) &&
- sgmii_pcs_scratch_test(priv, 0x5a5a)) {
- netdev_info(dev, "PCS PHY ID: 0x%04x%04x\n",
- sgmii_pcs_read(priv, MII_PHYSID1),
- sgmii_pcs_read(priv, MII_PHYSID2));
- } else {
- netdev_err(dev, "SGMII PCS Scratch memory test failed.\n");
- return -ENOMEM;
- }
-
- /* Starting on page 5-29 of the MegaCore Function User Guide
- * Set SGMII Link timer to 1.6ms
- */
- sgmii_pcs_write(priv, SGMII_PCS_LINK_TIMER_0, 0x0D40);
- sgmii_pcs_write(priv, SGMII_PCS_LINK_TIMER_1, 0x03);
-
- /* Enable SGMII Interface and Enable SGMII Auto Negotiation */
- sgmii_pcs_write(priv, SGMII_PCS_IF_MODE, 0x3);
-
- /* Enable Autonegotiation */
- tmp_reg = sgmii_pcs_read(priv, MII_BMCR);
- tmp_reg |= (BMCR_SPEED1000 | BMCR_FULLDPLX | BMCR_ANENABLE);
- sgmii_pcs_write(priv, MII_BMCR, tmp_reg);
-
- return sgmii_pcs_reset(priv);
-}
-
/* Open and initialize the interface
*/
static int tse_open(struct net_device *dev)
@@ -1176,14 +927,6 @@ static int tse_open(struct net_device *dev)
netdev_warn(dev, "TSE revision %x\n", priv->revision);

spin_lock(&priv->mac_cfg_lock);
- /* no-op if MAC not operating in SGMII mode*/
- ret = init_sgmii_pcs(dev);
- if (ret) {
- netdev_err(dev,
- "Cannot init the SGMII PCS (error: %d)\n", ret);
- spin_unlock(&priv->mac_cfg_lock);
- goto phy_error;
- }

ret = reset_mac(priv);
/* Note that reset_mac will fail if the clocks are gated by the PHY
@@ -1241,8 +984,12 @@ static int tse_open(struct net_device *dev)

spin_unlock_irqrestore(&priv->rxdma_irq_lock, flags);

- if (dev->phydev)
- phy_start(dev->phydev);
+ ret = phylink_of_phy_connect(priv->phylink, priv->device->of_node, 0);
+ if (ret) {
+ netdev_err(dev, "could not connect phylink (%d)\n", ret);
+ goto tx_request_irq_error;
+ }
+ phylink_start(priv->phylink);

napi_enable(&priv->napi);
netif_start_queue(dev);
@@ -1273,10 +1020,7 @@ static int tse_shutdown(struct net_device *dev)
int ret;
unsigned long int flags;

- /* Stop the PHY */
- if (dev->phydev)
- phy_stop(dev->phydev);
-
+ phylink_stop(priv->phylink);
netif_stop_queue(dev);
napi_disable(&priv->napi);

@@ -1322,6 +1066,111 @@ static struct net_device_ops altera_tse_netdev_ops = {
.ndo_validate_addr = eth_validate_addr,
};

+static void alt_tse_mac_link_state(struct phylink_config *config,
+ struct phylink_link_state *state)
+{
+ struct net_device *ndev = to_net_dev(config->dev);
+ struct altera_tse_private *priv = netdev_priv(ndev);
+
+ u16 bmsr, lpa;
+
+ bmsr = sgmii_pcs_read(priv, MII_BMSR);
+ lpa = sgmii_pcs_read(priv, MII_LPA);
+
+ phylink_mii_c22_pcs_decode_state(state, bmsr, lpa);
+}
+
+static void alt_tse_mac_an_restart(struct phylink_config *config)
+{
+ struct net_device *ndev = to_net_dev(config->dev);
+ struct altera_tse_private *priv = netdev_priv(ndev);
+ u16 bmcr;
+
+ bmcr = sgmii_pcs_read(priv, MII_BMCR);
+ bmcr |= BMCR_ANRESTART;
+ sgmii_pcs_write(priv, MII_BMCR, bmcr);
+}
+
+static void alt_tse_pcs_config(struct net_device *ndev,
+ const struct phylink_link_state *state)
+{
+ struct altera_tse_private *priv = netdev_priv(ndev);
+ u32 ctrl, if_mode;
+
+ if (state->interface != PHY_INTERFACE_MODE_SGMII &&
+ state->interface != PHY_INTERFACE_MODE_1000BASEX)
+ return;
+
+ ctrl = sgmii_pcs_read(priv, MII_BMCR);
+ if_mode = sgmii_pcs_read(priv, SGMII_PCS_IF_MODE);
+
+ /* Set link timer to 1.6ms, as per the MegaCore Function User Guide */
+ sgmii_pcs_write(priv, SGMII_PCS_LINK_TIMER_0, 0x0D40);
+ sgmii_pcs_write(priv, SGMII_PCS_LINK_TIMER_1, 0x03);
+
+ if (state->interface == PHY_INTERFACE_MODE_SGMII) {
+ if_mode |= PCS_IF_MODE_USE_SGMII_AN | PCS_IF_MODE_SGMII_ENA;
+ } else if (state->interface == PHY_INTERFACE_MODE_1000BASEX) {
+ if_mode &= ~(PCS_IF_MODE_USE_SGMII_AN | PCS_IF_MODE_SGMII_ENA);
+ if_mode |= PCS_IF_MODE_SGMI_SPEED_1000;
+ }
+
+ ctrl |= (BMCR_SPEED1000 | BMCR_FULLDPLX | BMCR_ANENABLE);
+
+ sgmii_pcs_write(priv, MII_BMCR, ctrl);
+ sgmii_pcs_write(priv, SGMII_PCS_IF_MODE, if_mode);
+
+ sgmii_pcs_reset(priv);
+}
+
+static void alt_tse_mac_config(struct phylink_config *config, unsigned int mode,
+ const struct phylink_link_state *state)
+{
+ struct net_device *ndev = to_net_dev(config->dev);
+ struct altera_tse_private *priv = netdev_priv(ndev);
+ u32 ctrl;
+
+ ctrl = csrrd32(priv->mac_dev, tse_csroffs(command_config));
+ ctrl &= ~(MAC_CMDCFG_ENA_10 | MAC_CMDCFG_ETH_SPEED | MAC_CMDCFG_HD_ENA);
+
+ if (state->duplex == DUPLEX_HALF)
+ ctrl |= MAC_CMDCFG_HD_ENA;
+
+ if (state->speed == SPEED_1000)
+ ctrl |= MAC_CMDCFG_ETH_SPEED;
+ else if (state->speed == SPEED_10)
+ ctrl |= MAC_CMDCFG_ENA_10;
+
+ alt_tse_pcs_config(ndev, state);
+
+ spin_lock(&priv->mac_cfg_lock);
+ csrwr32(ctrl, priv->mac_dev, tse_csroffs(command_config));
+ reset_mac(priv);
+ tse_set_mac(priv, true);
+ spin_unlock(&priv->mac_cfg_lock);
+}
+
+static void alt_tse_mac_link_down(struct phylink_config *config,
+ unsigned int mode, phy_interface_t interface)
+{
+}
+
+static void alt_tse_mac_link_up(struct phylink_config *config,
+ struct phy_device *phy, unsigned int mode,
+ phy_interface_t interface, int speed,
+ int duplex, bool tx_pause, bool rx_pause)
+{
+}
+
+static const struct phylink_mac_ops alt_tse_phylink_ops = {
+ .validate = phylink_generic_validate,
+ .mac_pcs_get_state = alt_tse_mac_link_state,
+ .mac_an_restart = alt_tse_mac_an_restart,
+ .mac_config = alt_tse_mac_config,
+ .mac_link_down = alt_tse_mac_link_down,
+ .mac_link_up = alt_tse_mac_link_up,
+};
+
static int request_and_map(struct platform_device *pdev, const char *name,
struct resource **res, void __iomem **ptr)
{
@@ -1595,11 +1444,29 @@ static int altera_tse_probe(struct platform_device *pdev)
(unsigned long) control_port->start, priv->rx_irq,
priv->tx_irq);

- ret = init_phy(ndev);
- if (ret != 0) {
- netdev_err(ndev, "Cannot attach to PHY (error: %d)\n", ret);
+ priv->phylink_config.dev = &ndev->dev;
+ priv->phylink_config.type = PHYLINK_NETDEV;
+ priv->phylink_config.mac_capabilities = MAC_SYM_PAUSE | MAC_10 |
+ MAC_100 | MAC_1000FD;
+
+ phy_interface_set_rgmii(priv->phylink_config.supported_interfaces);
+ __set_bit(PHY_INTERFACE_MODE_MII,
+ priv->phylink_config.supported_interfaces);
+ __set_bit(PHY_INTERFACE_MODE_GMII,
+ priv->phylink_config.supported_interfaces);
+ __set_bit(PHY_INTERFACE_MODE_SGMII,
+ priv->phylink_config.supported_interfaces);
+ __set_bit(PHY_INTERFACE_MODE_1000BASEX,
+ priv->phylink_config.supported_interfaces);
+
+ priv->phylink = phylink_create(&priv->phylink_config,
+ of_fwnode_handle(priv->device->of_node),
+ priv->phy_iface, &alt_tse_phylink_ops);
+ if (IS_ERR(priv->phylink)) {
+ dev_err(&pdev->dev, "failed to create phylink\n");
goto err_init_phy;
}
+
return 0;

err_init_phy:
@@ -1619,16 +1486,10 @@ static int altera_tse_remove(struct platform_device *pdev)
struct net_device *ndev = platform_get_drvdata(pdev);
struct altera_tse_private *priv = netdev_priv(ndev);

- if (ndev->phydev) {
- phy_disconnect(ndev->phydev);
-
- if (of_phy_is_fixed_link(priv->device->of_node))
- of_phy_deregister_fixed_link(priv->device->of_node);
- }
-
platform_set_drvdata(pdev, NULL);
altera_tse_mdio_destroy(ndev);
unregister_netdev(ndev);
+ phylink_destroy(priv->phylink);
free_netdev(ndev);

return 0;
--
2.37.2