linux/drivers/net/phy/at803x.c
Daniel Mack 13a56b4493 net: phy: at803x: Add support for hardware reset
The AT8030 will enter a FIFO error mode if a packet is transmitted while
the cable is unplugged. This hardware issue is acknowledged by the
vendor, and the only proposed solution is to conduct a hardware reset
via the external pin each time the link goes down. There is apparantly
no way to fix up the state via the register set.

This patch adds support for reading a 'reset-gpios' property from the DT
node of the PHY. If present, this gpio is used to apply a hardware reset
each time a 'link down' condition is detected. All relevant registers
are read out before, and written back after the reset cycle.

Doing this every time the link goes down might seem like overkill, but
there is unfortunately no way of figuring out whether the PHY is in
such a lock-up state. Hence, this is the only way of reliably fixing up
things.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-06-21 15:50:00 -07:00

377 lines
9.1 KiB
C

/*
* drivers/net/phy/at803x.c
*
* Driver for Atheros 803x PHY
*
* Author: Matus Ujhelyi <ujhelyi.m@gmail.com>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
* Free Software Foundation; either version 2 of the License, or (at your
* option) any later version.
*/
#include <linux/phy.h>
#include <linux/module.h>
#include <linux/string.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/of_gpio.h>
#include <linux/gpio/consumer.h>
#define AT803X_INTR_ENABLE 0x12
#define AT803X_INTR_STATUS 0x13
#define AT803X_SMART_SPEED 0x14
#define AT803X_LED_CONTROL 0x18
#define AT803X_WOL_ENABLE 0x01
#define AT803X_DEVICE_ADDR 0x03
#define AT803X_LOC_MAC_ADDR_0_15_OFFSET 0x804C
#define AT803X_LOC_MAC_ADDR_16_31_OFFSET 0x804B
#define AT803X_LOC_MAC_ADDR_32_47_OFFSET 0x804A
#define AT803X_MMD_ACCESS_CONTROL 0x0D
#define AT803X_MMD_ACCESS_CONTROL_DATA 0x0E
#define AT803X_FUNC_DATA 0x4003
#define AT803X_INER 0x0012
#define AT803X_INER_INIT 0xec00
#define AT803X_INSR 0x0013
#define AT803X_DEBUG_ADDR 0x1D
#define AT803X_DEBUG_DATA 0x1E
#define AT803X_DEBUG_SYSTEM_MODE_CTRL 0x05
#define AT803X_DEBUG_RGMII_TX_CLK_DLY BIT(8)
#define ATH8030_PHY_ID 0x004dd076
#define ATH8031_PHY_ID 0x004dd074
#define ATH8035_PHY_ID 0x004dd072
MODULE_DESCRIPTION("Atheros 803x PHY driver");
MODULE_AUTHOR("Matus Ujhelyi");
MODULE_LICENSE("GPL");
struct at803x_priv {
bool phy_reset:1;
struct gpio_desc *gpiod_reset;
};
struct at803x_context {
u16 bmcr;
u16 advertise;
u16 control1000;
u16 int_enable;
u16 smart_speed;
u16 led_control;
};
/* save relevant PHY registers to private copy */
static void at803x_context_save(struct phy_device *phydev,
struct at803x_context *context)
{
context->bmcr = phy_read(phydev, MII_BMCR);
context->advertise = phy_read(phydev, MII_ADVERTISE);
context->control1000 = phy_read(phydev, MII_CTRL1000);
context->int_enable = phy_read(phydev, AT803X_INTR_ENABLE);
context->smart_speed = phy_read(phydev, AT803X_SMART_SPEED);
context->led_control = phy_read(phydev, AT803X_LED_CONTROL);
}
/* restore relevant PHY registers from private copy */
static void at803x_context_restore(struct phy_device *phydev,
const struct at803x_context *context)
{
phy_write(phydev, MII_BMCR, context->bmcr);
phy_write(phydev, MII_ADVERTISE, context->advertise);
phy_write(phydev, MII_CTRL1000, context->control1000);
phy_write(phydev, AT803X_INTR_ENABLE, context->int_enable);
phy_write(phydev, AT803X_SMART_SPEED, context->smart_speed);
phy_write(phydev, AT803X_LED_CONTROL, context->led_control);
}
static int at803x_set_wol(struct phy_device *phydev,
struct ethtool_wolinfo *wol)
{
struct net_device *ndev = phydev->attached_dev;
const u8 *mac;
int ret;
u32 value;
unsigned int i, offsets[] = {
AT803X_LOC_MAC_ADDR_32_47_OFFSET,
AT803X_LOC_MAC_ADDR_16_31_OFFSET,
AT803X_LOC_MAC_ADDR_0_15_OFFSET,
};
if (!ndev)
return -ENODEV;
if (wol->wolopts & WAKE_MAGIC) {
mac = (const u8 *) ndev->dev_addr;
if (!is_valid_ether_addr(mac))
return -EFAULT;
for (i = 0; i < 3; i++) {
phy_write(phydev, AT803X_MMD_ACCESS_CONTROL,
AT803X_DEVICE_ADDR);
phy_write(phydev, AT803X_MMD_ACCESS_CONTROL_DATA,
offsets[i]);
phy_write(phydev, AT803X_MMD_ACCESS_CONTROL,
AT803X_FUNC_DATA);
phy_write(phydev, AT803X_MMD_ACCESS_CONTROL_DATA,
mac[(i * 2) + 1] | (mac[(i * 2)] << 8));
}
value = phy_read(phydev, AT803X_INTR_ENABLE);
value |= AT803X_WOL_ENABLE;
ret = phy_write(phydev, AT803X_INTR_ENABLE, value);
if (ret)
return ret;
value = phy_read(phydev, AT803X_INTR_STATUS);
} else {
value = phy_read(phydev, AT803X_INTR_ENABLE);
value &= (~AT803X_WOL_ENABLE);
ret = phy_write(phydev, AT803X_INTR_ENABLE, value);
if (ret)
return ret;
value = phy_read(phydev, AT803X_INTR_STATUS);
}
return ret;
}
static void at803x_get_wol(struct phy_device *phydev,
struct ethtool_wolinfo *wol)
{
u32 value;
wol->supported = WAKE_MAGIC;
wol->wolopts = 0;
value = phy_read(phydev, AT803X_INTR_ENABLE);
if (value & AT803X_WOL_ENABLE)
wol->wolopts |= WAKE_MAGIC;
}
static int at803x_suspend(struct phy_device *phydev)
{
int value;
int wol_enabled;
mutex_lock(&phydev->lock);
value = phy_read(phydev, AT803X_INTR_ENABLE);
wol_enabled = value & AT803X_WOL_ENABLE;
value = phy_read(phydev, MII_BMCR);
if (wol_enabled)
value |= BMCR_ISOLATE;
else
value |= BMCR_PDOWN;
phy_write(phydev, MII_BMCR, value);
mutex_unlock(&phydev->lock);
return 0;
}
static int at803x_resume(struct phy_device *phydev)
{
int value;
mutex_lock(&phydev->lock);
value = phy_read(phydev, MII_BMCR);
value &= ~(BMCR_PDOWN | BMCR_ISOLATE);
phy_write(phydev, MII_BMCR, value);
mutex_unlock(&phydev->lock);
return 0;
}
static int at803x_probe(struct phy_device *phydev)
{
struct device *dev = &phydev->dev;
struct at803x_priv *priv;
priv = devm_kzalloc(dev, sizeof(priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->gpiod_reset = devm_gpiod_get(dev, "reset");
if (IS_ERR(priv->gpiod_reset))
priv->gpiod_reset = NULL;
else
gpiod_direction_output(priv->gpiod_reset, 1);
phydev->priv = priv;
return 0;
}
static int at803x_config_init(struct phy_device *phydev)
{
int ret;
ret = genphy_config_init(phydev);
if (ret < 0)
return ret;
if (phydev->interface == PHY_INTERFACE_MODE_RGMII_TXID) {
ret = phy_write(phydev, AT803X_DEBUG_ADDR,
AT803X_DEBUG_SYSTEM_MODE_CTRL);
if (ret)
return ret;
ret = phy_write(phydev, AT803X_DEBUG_DATA,
AT803X_DEBUG_RGMII_TX_CLK_DLY);
if (ret)
return ret;
}
return 0;
}
static int at803x_ack_interrupt(struct phy_device *phydev)
{
int err;
err = phy_read(phydev, AT803X_INSR);
return (err < 0) ? err : 0;
}
static int at803x_config_intr(struct phy_device *phydev)
{
int err;
int value;
value = phy_read(phydev, AT803X_INER);
if (phydev->interrupts == PHY_INTERRUPT_ENABLED)
err = phy_write(phydev, AT803X_INER,
value | AT803X_INER_INIT);
else
err = phy_write(phydev, AT803X_INER, 0);
return err;
}
static void at803x_link_change_notify(struct phy_device *phydev)
{
struct at803x_priv *priv = phydev->priv;
/*
* Conduct a hardware reset for AT8030 every time a link loss is
* signalled. This is necessary to circumvent a hardware bug that
* occurs when the cable is unplugged while TX packets are pending
* in the FIFO. In such cases, the FIFO enters an error mode it
* cannot recover from by software.
*/
if (phydev->drv->phy_id == ATH8030_PHY_ID) {
if (phydev->state == PHY_NOLINK) {
if (priv->gpiod_reset && !priv->phy_reset) {
struct at803x_context context;
at803x_context_save(phydev, &context);
gpiod_set_value(priv->gpiod_reset, 0);
msleep(1);
gpiod_set_value(priv->gpiod_reset, 1);
msleep(1);
at803x_context_restore(phydev, &context);
dev_dbg(&phydev->dev, "%s(): phy was reset\n",
__func__);
priv->phy_reset = true;
}
} else {
priv->phy_reset = false;
}
}
}
static struct phy_driver at803x_driver[] = {
{
/* ATHEROS 8035 */
.phy_id = ATH8035_PHY_ID,
.name = "Atheros 8035 ethernet",
.phy_id_mask = 0xffffffef,
.probe = at803x_probe,
.config_init = at803x_config_init,
.link_change_notify = at803x_link_change_notify,
.set_wol = at803x_set_wol,
.get_wol = at803x_get_wol,
.suspend = at803x_suspend,
.resume = at803x_resume,
.features = PHY_GBIT_FEATURES,
.flags = PHY_HAS_INTERRUPT,
.config_aneg = genphy_config_aneg,
.read_status = genphy_read_status,
.driver = {
.owner = THIS_MODULE,
},
}, {
/* ATHEROS 8030 */
.phy_id = ATH8030_PHY_ID,
.name = "Atheros 8030 ethernet",
.phy_id_mask = 0xffffffef,
.probe = at803x_probe,
.config_init = at803x_config_init,
.link_change_notify = at803x_link_change_notify,
.set_wol = at803x_set_wol,
.get_wol = at803x_get_wol,
.suspend = at803x_suspend,
.resume = at803x_resume,
.features = PHY_GBIT_FEATURES,
.flags = PHY_HAS_INTERRUPT,
.config_aneg = genphy_config_aneg,
.read_status = genphy_read_status,
.driver = {
.owner = THIS_MODULE,
},
}, {
/* ATHEROS 8031 */
.phy_id = ATH8031_PHY_ID,
.name = "Atheros 8031 ethernet",
.phy_id_mask = 0xffffffef,
.probe = at803x_probe,
.config_init = at803x_config_init,
.link_change_notify = at803x_link_change_notify,
.set_wol = at803x_set_wol,
.get_wol = at803x_get_wol,
.suspend = at803x_suspend,
.resume = at803x_resume,
.features = PHY_GBIT_FEATURES,
.flags = PHY_HAS_INTERRUPT,
.config_aneg = genphy_config_aneg,
.read_status = genphy_read_status,
.ack_interrupt = &at803x_ack_interrupt,
.config_intr = &at803x_config_intr,
.driver = {
.owner = THIS_MODULE,
},
} };
static int __init atheros_init(void)
{
return phy_drivers_register(at803x_driver,
ARRAY_SIZE(at803x_driver));
}
static void __exit atheros_exit(void)
{
phy_drivers_unregister(at803x_driver, ARRAY_SIZE(at803x_driver));
}
module_init(atheros_init);
module_exit(atheros_exit);
static struct mdio_device_id __maybe_unused atheros_tbl[] = {
{ ATH8030_PHY_ID, 0xffffffef },
{ ATH8031_PHY_ID, 0xffffffef },
{ ATH8035_PHY_ID, 0xffffffef },
{ }
};
MODULE_DEVICE_TABLE(mdio, atheros_tbl);