diff options
Diffstat (limited to 'drivers/net/pcs/pcs-altera-tse.c')
| -rw-r--r-- | drivers/net/pcs/pcs-altera-tse.c | 175 |
1 files changed, 175 insertions, 0 deletions
diff --git a/drivers/net/pcs/pcs-altera-tse.c b/drivers/net/pcs/pcs-altera-tse.c new file mode 100644 index 000000000000..97a7cabff962 --- /dev/null +++ b/drivers/net/pcs/pcs-altera-tse.c @@ -0,0 +1,175 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2022 Bootlin + * + * Maxime Chevallier <maxime.chevallier@bootlin.com> + */ + +#include <linux/netdevice.h> +#include <linux/phy.h> +#include <linux/phylink.h> +#include <linux/pcs-altera-tse.h> + +/* SGMII PCS register addresses + */ +#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 */ + +struct altera_tse_pcs { + struct phylink_pcs pcs; + void __iomem *base; + int reg_width; +}; + +static struct altera_tse_pcs *phylink_pcs_to_tse_pcs(struct phylink_pcs *pcs) +{ + return container_of(pcs, struct altera_tse_pcs, pcs); +} + +static u16 tse_pcs_read(struct altera_tse_pcs *tse_pcs, int regnum) +{ + if (tse_pcs->reg_width == 4) + return readl(tse_pcs->base + regnum * 4); + else + return readw(tse_pcs->base + regnum * 2); +} + +static void tse_pcs_write(struct altera_tse_pcs *tse_pcs, int regnum, + u16 value) +{ + if (tse_pcs->reg_width == 4) + writel(value, tse_pcs->base + regnum * 4); + else + writew(value, tse_pcs->base + regnum * 2); +} + +static int tse_pcs_reset(struct altera_tse_pcs *tse_pcs) +{ + int i = 0; + u16 bmcr; + + /* Reset PCS block */ + bmcr = tse_pcs_read(tse_pcs, MII_BMCR); + bmcr |= BMCR_RESET; + tse_pcs_write(tse_pcs, MII_BMCR, bmcr); + + for (i = 0; i < SGMII_PCS_SW_RESET_TIMEOUT; i++) { + if (!(tse_pcs_read(tse_pcs, MII_BMCR) & BMCR_RESET)) + return 0; + udelay(1); + } + + return -ETIMEDOUT; +} + +static int alt_tse_pcs_validate(struct phylink_pcs *pcs, + unsigned long *supported, + const struct phylink_link_state *state) +{ + if (state->interface == PHY_INTERFACE_MODE_SGMII || + state->interface == PHY_INTERFACE_MODE_1000BASEX) + return 1; + + return -EINVAL; +} + +static int alt_tse_pcs_config(struct phylink_pcs *pcs, unsigned int mode, + phy_interface_t interface, + const unsigned long *advertising, + bool permit_pause_to_mac) +{ + struct altera_tse_pcs *tse_pcs = phylink_pcs_to_tse_pcs(pcs); + u32 ctrl, if_mode; + + ctrl = tse_pcs_read(tse_pcs, MII_BMCR); + if_mode = tse_pcs_read(tse_pcs, SGMII_PCS_IF_MODE); + + /* Set link timer to 1.6ms, as per the MegaCore Function User Guide */ + tse_pcs_write(tse_pcs, SGMII_PCS_LINK_TIMER_0, 0x0D40); + tse_pcs_write(tse_pcs, SGMII_PCS_LINK_TIMER_1, 0x03); + + if (interface == PHY_INTERFACE_MODE_SGMII) { + if_mode |= PCS_IF_MODE_USE_SGMII_AN | PCS_IF_MODE_SGMII_ENA; + } else if (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); + + tse_pcs_write(tse_pcs, MII_BMCR, ctrl); + tse_pcs_write(tse_pcs, SGMII_PCS_IF_MODE, if_mode); + + return tse_pcs_reset(tse_pcs); +} + +static void alt_tse_pcs_get_state(struct phylink_pcs *pcs, + struct phylink_link_state *state) +{ + struct altera_tse_pcs *tse_pcs = phylink_pcs_to_tse_pcs(pcs); + u16 bmsr, lpa; + + bmsr = tse_pcs_read(tse_pcs, MII_BMSR); + lpa = tse_pcs_read(tse_pcs, MII_LPA); + + phylink_mii_c22_pcs_decode_state(state, bmsr, lpa); +} + +static void alt_tse_pcs_an_restart(struct phylink_pcs *pcs) +{ + struct altera_tse_pcs *tse_pcs = phylink_pcs_to_tse_pcs(pcs); + u16 bmcr; + + bmcr = tse_pcs_read(tse_pcs, MII_BMCR); + bmcr |= BMCR_ANRESTART; + tse_pcs_write(tse_pcs, MII_BMCR, bmcr); + + /* This PCS seems to require a soft reset to re-sync the AN logic */ + tse_pcs_reset(tse_pcs); +} + +static const struct phylink_pcs_ops alt_tse_pcs_ops = { + .pcs_validate = alt_tse_pcs_validate, + .pcs_get_state = alt_tse_pcs_get_state, + .pcs_config = alt_tse_pcs_config, + .pcs_an_restart = alt_tse_pcs_an_restart, +}; + +struct phylink_pcs *alt_tse_pcs_create(struct net_device *ndev, + void __iomem *pcs_base, int reg_width) +{ + struct altera_tse_pcs *tse_pcs; + + if (reg_width != 4 && reg_width != 2) + return ERR_PTR(-EINVAL); + + tse_pcs = devm_kzalloc(&ndev->dev, sizeof(*tse_pcs), GFP_KERNEL); + if (!tse_pcs) + return ERR_PTR(-ENOMEM); + + tse_pcs->pcs.ops = &alt_tse_pcs_ops; + tse_pcs->base = pcs_base; + tse_pcs->reg_width = reg_width; + + return &tse_pcs->pcs; +} +EXPORT_SYMBOL_GPL(alt_tse_pcs_create); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Altera TSE PCS driver"); +MODULE_AUTHOR("Maxime Chevallier <maxime.chevallier@bootlin.com>"); |