https://github.com/torvalds/linux
Tip revision: 830b3c68c1fb1e9176028d02ef86f3cf76aa2476 authored by Linus Torvalds on 11 December 2022, 22:15:18 UTC
Linux 6.1
Linux 6.1
Tip revision: 830b3c6
pcs-lynx.c
// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
/* Copyright 2020 NXP
* Lynx PCS MDIO helpers
*/
#include <linux/mdio.h>
#include <linux/phylink.h>
#include <linux/pcs-lynx.h>
#define SGMII_CLOCK_PERIOD_NS 8 /* PCS is clocked at 125 MHz */
#define LINK_TIMER_VAL(ns) ((u32)((ns) / SGMII_CLOCK_PERIOD_NS))
#define SGMII_AN_LINK_TIMER_NS 1600000 /* defined by SGMII spec */
#define IEEE8023_LINK_TIMER_NS 10000000
#define LINK_TIMER_LO 0x12
#define LINK_TIMER_HI 0x13
#define IF_MODE 0x14
#define IF_MODE_SGMII_EN BIT(0)
#define IF_MODE_USE_SGMII_AN BIT(1)
#define IF_MODE_SPEED(x) (((x) << 2) & GENMASK(3, 2))
#define IF_MODE_SPEED_MSK GENMASK(3, 2)
#define IF_MODE_HALF_DUPLEX BIT(4)
struct lynx_pcs {
struct phylink_pcs pcs;
struct mdio_device *mdio;
};
enum sgmii_speed {
SGMII_SPEED_10 = 0,
SGMII_SPEED_100 = 1,
SGMII_SPEED_1000 = 2,
SGMII_SPEED_2500 = 2,
};
#define phylink_pcs_to_lynx(pl_pcs) container_of((pl_pcs), struct lynx_pcs, pcs)
#define lynx_to_phylink_pcs(lynx) (&(lynx)->pcs)
struct mdio_device *lynx_get_mdio_device(struct phylink_pcs *pcs)
{
struct lynx_pcs *lynx = phylink_pcs_to_lynx(pcs);
return lynx->mdio;
}
EXPORT_SYMBOL(lynx_get_mdio_device);
static void lynx_pcs_get_state_usxgmii(struct mdio_device *pcs,
struct phylink_link_state *state)
{
struct mii_bus *bus = pcs->bus;
int addr = pcs->addr;
int status, lpa;
status = mdiobus_c45_read(bus, addr, MDIO_MMD_VEND2, MII_BMSR);
if (status < 0)
return;
state->link = !!(status & MDIO_STAT1_LSTATUS);
state->an_complete = !!(status & MDIO_AN_STAT1_COMPLETE);
if (!state->link || !state->an_complete)
return;
lpa = mdiobus_c45_read(bus, addr, MDIO_MMD_VEND2, MII_LPA);
if (lpa < 0)
return;
phylink_decode_usxgmii_word(state, lpa);
}
static void lynx_pcs_get_state_2500basex(struct mdio_device *pcs,
struct phylink_link_state *state)
{
int bmsr, lpa;
bmsr = mdiodev_read(pcs, MII_BMSR);
lpa = mdiodev_read(pcs, MII_LPA);
if (bmsr < 0 || lpa < 0) {
state->link = false;
return;
}
state->link = !!(bmsr & BMSR_LSTATUS);
state->an_complete = !!(bmsr & BMSR_ANEGCOMPLETE);
if (!state->link)
return;
state->speed = SPEED_2500;
state->pause |= MLO_PAUSE_TX | MLO_PAUSE_RX;
state->duplex = DUPLEX_FULL;
}
static void lynx_pcs_get_state(struct phylink_pcs *pcs,
struct phylink_link_state *state)
{
struct lynx_pcs *lynx = phylink_pcs_to_lynx(pcs);
switch (state->interface) {
case PHY_INTERFACE_MODE_1000BASEX:
case PHY_INTERFACE_MODE_SGMII:
case PHY_INTERFACE_MODE_QSGMII:
phylink_mii_c22_pcs_get_state(lynx->mdio, state);
break;
case PHY_INTERFACE_MODE_2500BASEX:
lynx_pcs_get_state_2500basex(lynx->mdio, state);
break;
case PHY_INTERFACE_MODE_USXGMII:
lynx_pcs_get_state_usxgmii(lynx->mdio, state);
break;
case PHY_INTERFACE_MODE_10GBASER:
phylink_mii_c45_pcs_get_state(lynx->mdio, state);
break;
default:
break;
}
dev_dbg(&lynx->mdio->dev,
"mode=%s/%s/%s link=%u an_enabled=%u an_complete=%u\n",
phy_modes(state->interface),
phy_speed_to_str(state->speed),
phy_duplex_to_str(state->duplex),
state->link, state->an_enabled, state->an_complete);
}
static int lynx_pcs_config_giga(struct mdio_device *pcs, unsigned int mode,
phy_interface_t interface,
const unsigned long *advertising)
{
u32 link_timer;
u16 if_mode;
int err;
if (interface == PHY_INTERFACE_MODE_1000BASEX) {
link_timer = LINK_TIMER_VAL(IEEE8023_LINK_TIMER_NS);
mdiodev_write(pcs, LINK_TIMER_LO, link_timer & 0xffff);
mdiodev_write(pcs, LINK_TIMER_HI, link_timer >> 16);
if_mode = 0;
} else {
if_mode = IF_MODE_SGMII_EN;
if (mode == MLO_AN_INBAND) {
if_mode |= IF_MODE_USE_SGMII_AN;
/* Adjust link timer for SGMII */
link_timer = LINK_TIMER_VAL(SGMII_AN_LINK_TIMER_NS);
mdiodev_write(pcs, LINK_TIMER_LO, link_timer & 0xffff);
mdiodev_write(pcs, LINK_TIMER_HI, link_timer >> 16);
}
}
err = mdiodev_modify(pcs, IF_MODE,
IF_MODE_SGMII_EN | IF_MODE_USE_SGMII_AN,
if_mode);
if (err)
return err;
return phylink_mii_c22_pcs_config(pcs, mode, interface, advertising);
}
static int lynx_pcs_config_usxgmii(struct mdio_device *pcs, unsigned int mode,
const unsigned long *advertising)
{
struct mii_bus *bus = pcs->bus;
int addr = pcs->addr;
if (!phylink_autoneg_inband(mode)) {
dev_err(&pcs->dev, "USXGMII only supports in-band AN for now\n");
return -EOPNOTSUPP;
}
/* Configure device ability for the USXGMII Replicator */
return mdiobus_c45_write(bus, addr, MDIO_MMD_VEND2, MII_ADVERTISE,
MDIO_USXGMII_10G | MDIO_USXGMII_LINK |
MDIO_USXGMII_FULL_DUPLEX |
ADVERTISE_SGMII | ADVERTISE_LPACK);
}
static int lynx_pcs_config(struct phylink_pcs *pcs, unsigned int mode,
phy_interface_t ifmode,
const unsigned long *advertising,
bool permit)
{
struct lynx_pcs *lynx = phylink_pcs_to_lynx(pcs);
switch (ifmode) {
case PHY_INTERFACE_MODE_1000BASEX:
case PHY_INTERFACE_MODE_SGMII:
case PHY_INTERFACE_MODE_QSGMII:
return lynx_pcs_config_giga(lynx->mdio, mode, ifmode,
advertising);
case PHY_INTERFACE_MODE_2500BASEX:
if (phylink_autoneg_inband(mode)) {
dev_err(&lynx->mdio->dev,
"AN not supported on 3.125GHz SerDes lane\n");
return -EOPNOTSUPP;
}
break;
case PHY_INTERFACE_MODE_USXGMII:
return lynx_pcs_config_usxgmii(lynx->mdio, mode, advertising);
case PHY_INTERFACE_MODE_10GBASER:
/* Nothing to do here for 10GBASER */
break;
default:
return -EOPNOTSUPP;
}
return 0;
}
static void lynx_pcs_an_restart(struct phylink_pcs *pcs)
{
struct lynx_pcs *lynx = phylink_pcs_to_lynx(pcs);
phylink_mii_c22_pcs_an_restart(lynx->mdio);
}
static void lynx_pcs_link_up_sgmii(struct mdio_device *pcs, unsigned int mode,
int speed, int duplex)
{
u16 if_mode = 0, sgmii_speed;
/* The PCS needs to be configured manually only
* when not operating on in-band mode
*/
if (mode == MLO_AN_INBAND)
return;
if (duplex == DUPLEX_HALF)
if_mode |= IF_MODE_HALF_DUPLEX;
switch (speed) {
case SPEED_1000:
sgmii_speed = SGMII_SPEED_1000;
break;
case SPEED_100:
sgmii_speed = SGMII_SPEED_100;
break;
case SPEED_10:
sgmii_speed = SGMII_SPEED_10;
break;
case SPEED_UNKNOWN:
/* Silently don't do anything */
return;
default:
dev_err(&pcs->dev, "Invalid PCS speed %d\n", speed);
return;
}
if_mode |= IF_MODE_SPEED(sgmii_speed);
mdiodev_modify(pcs, IF_MODE,
IF_MODE_HALF_DUPLEX | IF_MODE_SPEED_MSK,
if_mode);
}
/* 2500Base-X is SerDes protocol 7 on Felix and 6 on ENETC. It is a SerDes lane
* clocked at 3.125 GHz which encodes symbols with 8b/10b and does not have
* auto-negotiation of any link parameters. Electrically it is compatible with
* a single lane of XAUI.
* The hardware reference manual wants to call this mode SGMII, but it isn't
* really, since the fundamental features of SGMII:
* - Downgrading the link speed by duplicating symbols
* - Auto-negotiation
* are not there.
* The speed is configured at 1000 in the IF_MODE because the clock frequency
* is actually given by a PLL configured in the Reset Configuration Word (RCW).
* Since there is no difference between fixed speed SGMII w/o AN and 802.3z w/o
* AN, we call this PHY interface type 2500Base-X. In case a PHY negotiates a
* lower link speed on line side, the system-side interface remains fixed at
* 2500 Mbps and we do rate adaptation through pause frames.
*/
static void lynx_pcs_link_up_2500basex(struct mdio_device *pcs,
unsigned int mode,
int speed, int duplex)
{
u16 if_mode = 0;
if (mode == MLO_AN_INBAND) {
dev_err(&pcs->dev, "AN not supported for 2500BaseX\n");
return;
}
if (duplex == DUPLEX_HALF)
if_mode |= IF_MODE_HALF_DUPLEX;
if_mode |= IF_MODE_SPEED(SGMII_SPEED_2500);
mdiodev_modify(pcs, IF_MODE,
IF_MODE_HALF_DUPLEX | IF_MODE_SPEED_MSK,
if_mode);
}
static void lynx_pcs_link_up(struct phylink_pcs *pcs, unsigned int mode,
phy_interface_t interface,
int speed, int duplex)
{
struct lynx_pcs *lynx = phylink_pcs_to_lynx(pcs);
switch (interface) {
case PHY_INTERFACE_MODE_SGMII:
case PHY_INTERFACE_MODE_QSGMII:
lynx_pcs_link_up_sgmii(lynx->mdio, mode, speed, duplex);
break;
case PHY_INTERFACE_MODE_2500BASEX:
lynx_pcs_link_up_2500basex(lynx->mdio, mode, speed, duplex);
break;
case PHY_INTERFACE_MODE_USXGMII:
/* At the moment, only in-band AN is supported for USXGMII
* so nothing to do in link_up
*/
break;
default:
break;
}
}
static const struct phylink_pcs_ops lynx_pcs_phylink_ops = {
.pcs_get_state = lynx_pcs_get_state,
.pcs_config = lynx_pcs_config,
.pcs_an_restart = lynx_pcs_an_restart,
.pcs_link_up = lynx_pcs_link_up,
};
struct phylink_pcs *lynx_pcs_create(struct mdio_device *mdio)
{
struct lynx_pcs *lynx;
lynx = kzalloc(sizeof(*lynx), GFP_KERNEL);
if (!lynx)
return NULL;
lynx->mdio = mdio;
lynx->pcs.ops = &lynx_pcs_phylink_ops;
lynx->pcs.poll = true;
return lynx_to_phylink_pcs(lynx);
}
EXPORT_SYMBOL(lynx_pcs_create);
void lynx_pcs_destroy(struct phylink_pcs *pcs)
{
struct lynx_pcs *lynx = phylink_pcs_to_lynx(pcs);
kfree(lynx);
}
EXPORT_SYMBOL(lynx_pcs_destroy);
MODULE_LICENSE("Dual BSD/GPL");