From 4a502cf4d77e12119e7061a05d5789cd3129d185 Mon Sep 17 00:00:00 2001 From: Maxime Chevallier Date: Fri, 2 Sep 2022 10:32:03 +0200 Subject: [PATCH] net: pcs: add new PCS driver for altera TSE PCS The Altera Triple Speed Ethernet has a SGMII/1000BaseC PCS that can be integrated in several ways. It can either be part of the TSE MAC's address space, accessed through 32 bits accesses on the mapped mdio device 0, or through a dedicated 16 bits register set. This driver allows using the TSE PCS outside of altera TSE's driver, since it can be used standalone by other MACs. Signed-off-by: Maxime Chevallier Signed-off-by: David S. Miller --- MAINTAINERS | 7 ++ drivers/net/pcs/Kconfig | 6 ++ drivers/net/pcs/Makefile | 1 + drivers/net/pcs/pcs-altera-tse.c | 175 +++++++++++++++++++++++++++++++++++++++ include/linux/pcs-altera-tse.h | 17 ++++ 5 files changed, 206 insertions(+) create mode 100644 drivers/net/pcs/pcs-altera-tse.c create mode 100644 include/linux/pcs-altera-tse.h diff --git a/MAINTAINERS b/MAINTAINERS index 9479f77..9688a27 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -878,6 +878,13 @@ L: netdev@vger.kernel.org S: Maintained F: drivers/net/ethernet/altera/ +ALTERA TSE PCS +M: Maxime Chevallier +L: netdev@vger.kernel.org +S: Supported +F: drivers/net/pcs/pcs-altera-tse.c +F: include/linux/pcs-altera-tse.h + ALTERA UART/JTAG UART SERIAL DRIVERS M: Tobias Klauser L: linux-serial@vger.kernel.org diff --git a/drivers/net/pcs/Kconfig b/drivers/net/pcs/Kconfig index 6289b7c..6e7e6c346 100644 --- a/drivers/net/pcs/Kconfig +++ b/drivers/net/pcs/Kconfig @@ -26,4 +26,10 @@ config PCS_RZN1_MIIC on RZ/N1 SoCs. This PCS converts MII to RMII/RGMII or can be set in pass-through mode for MII. +config PCS_ALTERA_TSE + tristate + help + This module provides helper functions for the Altera Triple Speed + Ethernet SGMII PCS, that can be found on the Intel Socfpga family. + endmenu diff --git a/drivers/net/pcs/Makefile b/drivers/net/pcs/Makefile index 0ff5388..4c780d8 100644 --- a/drivers/net/pcs/Makefile +++ b/drivers/net/pcs/Makefile @@ -6,3 +6,4 @@ pcs_xpcs-$(CONFIG_PCS_XPCS) := pcs-xpcs.o pcs-xpcs-nxp.o obj-$(CONFIG_PCS_XPCS) += pcs_xpcs.o obj-$(CONFIG_PCS_LYNX) += pcs-lynx.o obj-$(CONFIG_PCS_RZN1_MIIC) += pcs-rzn1-miic.o +obj-$(CONFIG_PCS_ALTERA_TSE) += pcs-altera-tse.o diff --git a/drivers/net/pcs/pcs-altera-tse.c b/drivers/net/pcs/pcs-altera-tse.c new file mode 100644 index 0000000..97a7cab --- /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 + */ + +#include +#include +#include +#include + +/* 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 "); diff --git a/include/linux/pcs-altera-tse.h b/include/linux/pcs-altera-tse.h new file mode 100644 index 0000000..92ab9f0 --- /dev/null +++ b/include/linux/pcs-altera-tse.h @@ -0,0 +1,17 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2022 Bootlin + * + * Maxime Chevallier + */ + +#ifndef __LINUX_PCS_ALTERA_TSE_H +#define __LINUX_PCS_ALTERA_TSE_H + +struct phylink_pcs; +struct net_device; + +struct phylink_pcs *alt_tse_pcs_create(struct net_device *ndev, + void __iomem *pcs_base, int reg_width); + +#endif /* __LINUX_PCS_ALTERA_TSE_H */ -- 2.7.4