diff options
author | Andy Fleming <afleming@freescale.com> | 2005-07-30 19:31:23 -0400 |
---|---|---|
committer | Jeff Garzik <jgarzik@pobox.com> | 2005-07-30 19:31:23 -0400 |
commit | 00db8189d984d6c51226dafbbe4a667ce9b7d5da (patch) | |
tree | f19468548c938523e3519670f8554e7a1b9c0c31 /drivers/net/phy/phy.c | |
parent | b0825488a642cadcf39709961dde61440cb0731c (diff) |
This patch adds a PHY Abstraction Layer to the Linux Kernel, enabling
ethernet drivers to remain as ignorant as is reasonable of the connected
PHY's design and operation details.
Signed-off-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: Jeff Garzik <jgarzik@pobox.com>
Diffstat (limited to 'drivers/net/phy/phy.c')
-rw-r--r-- | drivers/net/phy/phy.c | 862 |
1 files changed, 862 insertions, 0 deletions
diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c new file mode 100644 index 000000000000..e2c6896b92d2 --- /dev/null +++ b/drivers/net/phy/phy.c @@ -0,0 +1,862 @@ +/* + * drivers/net/phy/phy.c + * + * Framework for configuring and reading PHY devices + * Based on code in sungem_phy.c and gianfar_phy.c + * + * Author: Andy Fleming + * + * Copyright (c) 2004 Freescale Semiconductor, Inc. + * + * 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/config.h> +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/string.h> +#include <linux/errno.h> +#include <linux/unistd.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/init.h> +#include <linux/delay.h> +#include <linux/netdevice.h> +#include <linux/etherdevice.h> +#include <linux/skbuff.h> +#include <linux/spinlock.h> +#include <linux/mm.h> +#include <linux/module.h> +#include <linux/version.h> +#include <linux/mii.h> +#include <linux/ethtool.h> +#include <linux/phy.h> + +#include <asm/io.h> +#include <asm/irq.h> +#include <asm/uaccess.h> + +static void phy_change(void *data); +static void phy_timer(unsigned long data); + +/* Convenience function to print out the current phy status + */ +void phy_print_status(struct phy_device *phydev) +{ + pr_info("%s: Link is %s", phydev->dev.bus_id, + phydev->link ? "Up" : "Down"); + if (phydev->link) + printk(" - %d/%s", phydev->speed, + DUPLEX_FULL == phydev->duplex ? + "Full" : "Half"); + + printk("\n"); +} +EXPORT_SYMBOL(phy_print_status); + + +/* Convenience functions for reading/writing a given PHY + * register. They MUST NOT be called from interrupt context, + * because the bus read/write functions may wait for an interrupt + * to conclude the operation. */ +int phy_read(struct phy_device *phydev, u16 regnum) +{ + int retval; + struct mii_bus *bus = phydev->bus; + + spin_lock_bh(&bus->mdio_lock); + retval = bus->read(bus, phydev->addr, regnum); + spin_unlock_bh(&bus->mdio_lock); + + return retval; +} +EXPORT_SYMBOL(phy_read); + +int phy_write(struct phy_device *phydev, u16 regnum, u16 val) +{ + int err; + struct mii_bus *bus = phydev->bus; + + spin_lock_bh(&bus->mdio_lock); + err = bus->write(bus, phydev->addr, regnum, val); + spin_unlock_bh(&bus->mdio_lock); + + return err; +} +EXPORT_SYMBOL(phy_write); + + +int phy_clear_interrupt(struct phy_device *phydev) +{ + int err = 0; + + if (phydev->drv->ack_interrupt) + err = phydev->drv->ack_interrupt(phydev); + + return err; +} + + +int phy_config_interrupt(struct phy_device *phydev, u32 interrupts) +{ + int err = 0; + + phydev->interrupts = interrupts; + if (phydev->drv->config_intr) + err = phydev->drv->config_intr(phydev); + + return err; +} + + +/* phy_aneg_done + * + * description: Reads the status register and returns 0 either if + * auto-negotiation is incomplete, or if there was an error. + * Returns BMSR_ANEGCOMPLETE if auto-negotiation is done. + */ +static inline int phy_aneg_done(struct phy_device *phydev) +{ + int retval; + + retval = phy_read(phydev, MII_BMSR); + + return (retval < 0) ? retval : (retval & BMSR_ANEGCOMPLETE); +} + +/* phy_start_aneg + * + * description: Calls the PHY driver's config_aneg, and then + * sets the PHY state to PHY_AN if auto-negotiation is enabled, + * and to PHY_FORCING if auto-negotiation is disabled. Unless + * the PHY is currently HALTED. + */ +int phy_start_aneg(struct phy_device *phydev) +{ + int err; + + spin_lock(&phydev->lock); + + if (AUTONEG_DISABLE == phydev->autoneg) + phy_sanitize_settings(phydev); + + err = phydev->drv->config_aneg(phydev); + + if (err < 0) + goto out_unlock; + + if (phydev->state != PHY_HALTED) { + if (AUTONEG_ENABLE == phydev->autoneg) { + phydev->state = PHY_AN; + phydev->link_timeout = PHY_AN_TIMEOUT; + } else { + phydev->state = PHY_FORCING; + phydev->link_timeout = PHY_FORCE_TIMEOUT; + } + } + +out_unlock: + spin_unlock(&phydev->lock); + return err; +} +EXPORT_SYMBOL(phy_start_aneg); + + +/* A structure for mapping a particular speed and duplex + * combination to a particular SUPPORTED and ADVERTISED value */ +struct phy_setting { + int speed; + int duplex; + u32 setting; +}; + +/* A mapping of all SUPPORTED settings to speed/duplex */ +static struct phy_setting settings[] = { + { + .speed = 10000, + .duplex = DUPLEX_FULL, + .setting = SUPPORTED_10000baseT_Full, + }, + { + .speed = SPEED_1000, + .duplex = DUPLEX_FULL, + .setting = SUPPORTED_1000baseT_Full, + }, + { + .speed = SPEED_1000, + .duplex = DUPLEX_HALF, + .setting = SUPPORTED_1000baseT_Half, + }, + { + .speed = SPEED_100, + .duplex = DUPLEX_FULL, + .setting = SUPPORTED_100baseT_Full, + }, + { + .speed = SPEED_100, + .duplex = DUPLEX_HALF, + .setting = SUPPORTED_100baseT_Half, + }, + { + .speed = SPEED_10, + .duplex = DUPLEX_FULL, + .setting = SUPPORTED_10baseT_Full, + }, + { + .speed = SPEED_10, + .duplex = DUPLEX_HALF, + .setting = SUPPORTED_10baseT_Half, + }, +}; + +#define MAX_NUM_SETTINGS (sizeof(settings)/sizeof(struct phy_setting)) + +/* phy_find_setting + * + * description: Searches the settings array for the setting which + * matches the desired speed and duplex, and returns the index + * of that setting. Returns the index of the last setting if + * none of the others match. + */ +static inline int phy_find_setting(int speed, int duplex) +{ + int idx = 0; + + while (idx < ARRAY_SIZE(settings) && + (settings[idx].speed != speed || + settings[idx].duplex != duplex)) + idx++; + + return idx < MAX_NUM_SETTINGS ? idx : MAX_NUM_SETTINGS - 1; +} + +/* phy_find_valid + * idx: The first index in settings[] to search + * features: A mask of the valid settings + * + * description: Returns the index of the first valid setting less + * than or equal to the one pointed to by idx, as determined by + * the mask in features. Returns the index of the last setting + * if nothing else matches. + */ +static inline int phy_find_valid(int idx, u32 features) +{ + while (idx < MAX_NUM_SETTINGS && !(settings[idx].setting & features)) + idx++; + + return idx < MAX_NUM_SETTINGS ? idx : MAX_NUM_SETTINGS - 1; +} + +/* phy_sanitize_settings + * + * description: Make sure the PHY is set to supported speeds and + * duplexes. Drop down by one in this order: 1000/FULL, + * 1000/HALF, 100/FULL, 100/HALF, 10/FULL, 10/HALF + */ +void phy_sanitize_settings(struct phy_device *phydev) +{ + u32 features = phydev->supported; + int idx; + + /* Sanitize settings based on PHY capabilities */ + if ((features & SUPPORTED_Autoneg) == 0) + phydev->autoneg = 0; + + idx = phy_find_valid(phy_find_setting(phydev->speed, phydev->duplex), + features); + + phydev->speed = settings[idx].speed; + phydev->duplex = settings[idx].duplex; +} +EXPORT_SYMBOL(phy_sanitize_settings); + +/* phy_force_reduction + * + * description: Reduces the speed/duplex settings by + * one notch. The order is so: + * 1000/FULL, 1000/HALF, 100/FULL, 100/HALF, + * 10/FULL, 10/HALF. The function bottoms out at 10/HALF. + */ +static void phy_force_reduction(struct phy_device *phydev) +{ + int idx; + + idx = phy_find_setting(phydev->speed, phydev->duplex); + + idx++; + + idx = phy_find_valid(idx, phydev->supported); + + phydev->speed = settings[idx].speed; + phydev->duplex = settings[idx].duplex; + + pr_info("Trying %d/%s\n", phydev->speed, + DUPLEX_FULL == phydev->duplex ? + "FULL" : "HALF"); +} + +/* phy_ethtool_sset: + * A generic ethtool sset function. Handles all the details + * + * A few notes about parameter checking: + * - We don't set port or transceiver, so we don't care what they + * were set to. + * - phy_start_aneg() will make sure forced settings are sane, and + * choose the next best ones from the ones selected, so we don't + * care if ethtool tries to give us bad values + */ +int phy_ethtool_sset(struct phy_device *phydev, struct ethtool_cmd *cmd) +{ + if (cmd->phy_address != phydev->addr) + return -EINVAL; + + /* We make sure that we don't pass unsupported + * values in to the PHY */ + cmd->advertising &= phydev->supported; + + /* Verify the settings we care about. */ + if (cmd->autoneg != AUTONEG_ENABLE && cmd->autoneg != AUTONEG_DISABLE) + return -EINVAL; + + if (cmd->autoneg == AUTONEG_ENABLE && cmd->advertising == 0) + return -EINVAL; + + if (cmd->autoneg == AUTONEG_DISABLE + && ((cmd->speed != SPEED_1000 + && cmd->speed != SPEED_100 + && cmd->speed != SPEED_10) + || (cmd->duplex != DUPLEX_HALF + && cmd->duplex != DUPLEX_FULL))) + return -EINVAL; + + phydev->autoneg = cmd->autoneg; + + phydev->speed = cmd->speed; + + phydev->advertising = cmd->advertising; + + if (AUTONEG_ENABLE == cmd->autoneg) + phydev->advertising |= ADVERTISED_Autoneg; + else + phydev->advertising &= ~ADVERTISED_Autoneg; + + phydev->duplex = cmd->duplex; + + /* Restart the PHY */ + phy_start_aneg(phydev); + + return 0; +} + +int phy_ethtool_gset(struct phy_device *phydev, struct ethtool_cmd *cmd) +{ + cmd->supported = phydev->supported; + + cmd->advertising = phydev->advertising; + + cmd->speed = phydev->speed; + cmd->duplex = phydev->duplex; + cmd->port = PORT_MII; + cmd->phy_address = phydev->addr; + cmd->transceiver = XCVR_EXTERNAL; + cmd->autoneg = phydev->autoneg; + + return 0; +} + + +/* Note that this function is currently incompatible with the + * PHYCONTROL layer. It changes registers without regard to + * current state. Use at own risk + */ +int phy_mii_ioctl(struct phy_device *phydev, + struct mii_ioctl_data *mii_data, int cmd) +{ + u16 val = mii_data->val_in; + + switch (cmd) { + case SIOCGMIIPHY: + mii_data->phy_id = phydev->addr; + break; + case SIOCGMIIREG: + mii_data->val_out = phy_read(phydev, mii_data->reg_num); + break; + + case SIOCSMIIREG: + if (!capable(CAP_NET_ADMIN)) + return -EPERM; + + if (mii_data->phy_id == phydev->addr) { + switch(mii_data->reg_num) { + case MII_BMCR: + if (val & (BMCR_RESET|BMCR_ANENABLE)) + phydev->autoneg = AUTONEG_DISABLE; + else + phydev->autoneg = AUTONEG_ENABLE; + if ((!phydev->autoneg) && (val & BMCR_FULLDPLX)) + phydev->duplex = DUPLEX_FULL; + else + phydev->duplex = DUPLEX_HALF; + break; + case MII_ADVERTISE: + phydev->advertising = val; + break; + default: + /* do nothing */ + break; + } + } + + phy_write(phydev, mii_data->reg_num, val); + + if (mii_data->reg_num == MII_BMCR + && val & BMCR_RESET + && phydev->drv->config_init) + phydev->drv->config_init(phydev); + break; + } + + return 0; +} + +/* phy_start_machine: + * + * description: The PHY infrastructure can run a state machine + * which tracks whether the PHY is starting up, negotiating, + * etc. This function starts the timer which tracks the state + * of the PHY. If you want to be notified when the state + * changes, pass in the callback, otherwise, pass NULL. If you + * want to maintain your own state machine, do not call this + * function. */ +void phy_start_machine(struct phy_device *phydev, + void (*handler)(struct net_device *)) +{ + phydev->adjust_state = handler; + + init_timer(&phydev->phy_timer); + phydev->phy_timer.function = &phy_timer; + phydev->phy_timer.data = (unsigned long) phydev; + mod_timer(&phydev->phy_timer, jiffies + HZ); +} + +/* phy_stop_machine + * + * description: Stops the state machine timer, sets the state to + * UP (unless it wasn't up yet), and then frees the interrupt, + * if it is in use. This function must be called BEFORE + * phy_detach. + */ +void phy_stop_machine(struct phy_device *phydev) +{ + del_timer_sync(&phydev->phy_timer); + + spin_lock(&phydev->lock); + if (phydev->state > PHY_UP) + phydev->state = PHY_UP; + spin_unlock(&phydev->lock); + + if (phydev->irq != PHY_POLL) + phy_stop_interrupts(phydev); + + phydev->adjust_state = NULL; +} + +#ifdef CONFIG_PHYCONTROL +/* phy_error: + * + * Moves the PHY to the HALTED state in response to a read + * or write error, and tells the controller the link is down. + * Must not be called from interrupt context, or while the + * phydev->lock is held. + */ +void phy_error(struct phy_device *phydev) +{ + spin_lock(&phydev->lock); + phydev->state = PHY_HALTED; + spin_unlock(&phydev->lock); +} + +/* phy_interrupt + * + * description: When a PHY interrupt occurs, the handler disables + * interrupts, and schedules a work task to clear the interrupt. + */ +static irqreturn_t phy_interrupt(int irq, void *phy_dat, struct pt_regs *regs) +{ + struct phy_device *phydev = phy_dat; + + /* The MDIO bus is not allowed to be written in interrupt + * context, so we need to disable the irq here. A work + * queue will write the PHY to disable and clear the + * interrupt, and then reenable the irq line. */ + disable_irq_nosync(irq); + + schedule_work(&phydev->phy_queue); + + return IRQ_HANDLED; +} + +/* Enable the interrupts from the PHY side */ +int phy_enable_interrupts(struct phy_device *phydev) +{ + int err; + + err = phy_clear_interrupt(phydev); + + if (err < 0) + return err; + + err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED); + + return err; +} +EXPORT_SYMBOL(phy_enable_interrupts); + +/* Disable the PHY interrupts from the PHY side */ +int phy_disable_interrupts(struct phy_device *phydev) +{ + int err; + + /* Disable PHY interrupts */ + err = phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED); + + if (err) + goto phy_err; + + /* Clear the interrupt */ + err = phy_clear_interrupt(phydev); + + if (err) + goto phy_err; + + return 0; + +phy_err: + phy_error(phydev); + + return err; +} +EXPORT_SYMBOL(phy_disable_interrupts); + +/* phy_start_interrupts + * + * description: Request the interrupt for the given PHY. If + * this fails, then we set irq to PHY_POLL. + * Otherwise, we enable the interrupts in the PHY. + * Returns 0 on success. + * This should only be called with a valid IRQ number. + */ +int phy_start_interrupts(struct phy_device *phydev) +{ + int err = 0; + + INIT_WORK(&phydev->phy_queue, phy_change, phydev); + + if (request_irq(phydev->irq, phy_interrupt, + SA_SHIRQ, + "phy_interrupt", + phydev) < 0) { + printk(KERN_WARNING "%s: Can't get IRQ %d (PHY)\n", + phydev->bus->name, + phydev->irq); + phydev->irq = PHY_POLL; + return 0; + } + + err = phy_enable_interrupts(phydev); + + return err; +} +EXPORT_SYMBOL(phy_start_interrupts); + +int phy_stop_interrupts(struct phy_device *phydev) +{ + int err; + + err = phy_disable_interrupts(phydev); + + if (err) + phy_error(phydev); + + free_irq(phydev->irq, phydev); + + return err; +} +EXPORT_SYMBOL(phy_stop_interrupts); + + +/* Scheduled by the phy_interrupt/timer to handle PHY changes */ +static void phy_change(void *data) +{ + int err; + struct phy_device *phydev = data; + + err = phy_disable_interrupts(phydev); + + if (err) + goto phy_err; + + spin_lock(&phydev->lock); + if ((PHY_RUNNING == phydev->state) || (PHY_NOLINK == phydev->state)) + phydev->state = PHY_CHANGELINK; + spin_unlock(&phydev->lock); + + enable_irq(phydev->irq); + + /* Reenable interrupts */ + err = phy_config_interrupt(phydev, PHY_INTERRUPT_ENABLED); + + if (err) + goto irq_enable_err; + + return; + +irq_enable_err: + disable_irq(phydev->irq); +phy_err: + phy_error(phydev); +} + +/* Bring down the PHY link, and stop checking the status. */ +void phy_stop(struct phy_device *phydev) +{ + spin_lock(&phydev->lock); + + if (PHY_HALTED == phydev->state) + goto out_unlock; + + if (phydev->irq != PHY_POLL) { + /* Clear any pending interrupts */ + phy_clear_interrupt(phydev); + + /* Disable PHY Interrupts */ + phy_config_interrupt(phydev, PHY_INTERRUPT_DISABLED); + } + + phydev->state = PHY_HALTED; + +out_unlock: + spin_unlock(&phydev->lock); +} + + +/* phy_start + * + * description: Indicates the attached device's readiness to + * handle PHY-related work. Used during startup to start the + * PHY, and after a call to phy_stop() to resume operation. + * Also used to indicate the MDIO bus has cleared an error + * condition. + */ +void phy_start(struct phy_device *phydev) +{ + spin_lock(&phydev->lock); + + switch (phydev->state) { + case PHY_STARTING: + phydev->state = PHY_PENDING; + break; + case PHY_READY: + phydev->state = PHY_UP; + break; + case PHY_HALTED: + phydev->state = PHY_RESUMING; + default: + break; + } + spin_unlock(&phydev->lock); +} +EXPORT_SYMBOL(phy_stop); +EXPORT_SYMBOL(phy_start); + +/* PHY timer which handles the state machine */ +static void phy_timer(unsigned long data) +{ + struct phy_device *phydev = (struct phy_device *)data; + int needs_aneg = 0; + int err = 0; + + spin_lock(&phydev->lock); + + if (phydev->adjust_state) + phydev->adjust_state(phydev->attached_dev); + + switch(phydev->state) { + case PHY_DOWN: + case PHY_STARTING: + case PHY_READY: + case PHY_PENDING: + break; + case PHY_UP: + needs_aneg = 1; + + phydev->link_timeout = PHY_AN_TIMEOUT; + + break; + case PHY_AN: + /* Check if negotiation is done. Break + * if there's an error */ + err = phy_aneg_done(phydev); + if (err < 0) + break; + + /* If auto-negotiation is done, we change to + * either RUNNING, or NOLINK */ + if (err > 0) { + err = phy_read_status(phydev); + + if (err) + break; + + if (phydev->link) { + phydev->state = PHY_RUNNING; + netif_carrier_on(phydev->attached_dev); + } else { + phydev->state = PHY_NOLINK; + netif_carrier_off(phydev->attached_dev); + } + + phydev->adjust_link(phydev->attached_dev); + + } else if (0 == phydev->link_timeout--) { + /* The counter expired, so either we + * switch to forced mode, or the + * magic_aneg bit exists, and we try aneg + * again */ + if (!(phydev->drv->flags & PHY_HAS_MAGICANEG)) { + int idx; + + /* We'll start from the + * fastest speed, and work + * our way down */ + idx = phy_find_valid(0, + phydev->supported); + + phydev->speed = settings[idx].speed; + phydev->duplex = settings[idx].duplex; + + phydev->autoneg = AUTONEG_DISABLE; + phydev->state = PHY_FORCING; + phydev->link_timeout = + PHY_FORCE_TIMEOUT; + + pr_info("Trying %d/%s\n", + phydev->speed, + DUPLEX_FULL == + phydev->duplex ? + "FULL" : "HALF"); + } + + needs_aneg = 1; + } + break; + case PHY_NOLINK: + err = phy_read_status(phydev); + + if (err) + break; + + if (phydev->link) { + phydev->state = PHY_RUNNING; + netif_carrier_on(phydev->attached_dev); + phydev->adjust_link(phydev->attached_dev); + } + break; + case PHY_FORCING: + err = phy_read_status(phydev); + + if (err) + break; + + if (phydev->link) { + phydev->state = PHY_RUNNING; + netif_carrier_on(phydev->attached_dev); + } else { + if (0 == phydev->link_timeout--) { + phy_force_reduction(phydev); + needs_aneg = 1; + } + } + + phydev->adjust_link(phydev->attached_dev); + break; + case PHY_RUNNING: + /* Only register a CHANGE if we are + * polling */ + if (PHY_POLL == phydev->irq) + phydev->state = PHY_CHANGELINK; + break; + case PHY_CHANGELINK: + err = phy_read_status(phydev); + + if (err) + break; + + if (phydev->link) { + phydev->state = PHY_RUNNING; + netif_carrier_on(phydev->attached_dev); + } else { + phydev->state = PHY_NOLINK; + netif_carrier_off(phydev->attached_dev); + } + + phydev->adjust_link(phydev->attached_dev); + + if (PHY_POLL != phydev->irq) + err = phy_config_interrupt(phydev, + PHY_INTERRUPT_ENABLED); + break; + case PHY_HALTED: + if (phydev->link) { + phydev->link = 0; + netif_carrier_off(phydev->attached_dev); + phydev->adjust_link(phydev->attached_dev); + } + break; + case PHY_RESUMING: + + err = phy_clear_interrupt(phydev); + + if (err) + break; + + err = phy_config_interrupt(phydev, + PHY_INTERRUPT_ENABLED); + + if (err) + break; + + if (AUTONEG_ENABLE == phydev->autoneg) { + err = phy_aneg_done(phydev); + if (err < 0) + break; + + /* err > 0 if AN is done. + * Otherwise, it's 0, and we're + * still waiting for AN */ + if (err > 0) { + phydev->state = PHY_RUNNING; + } else { + phydev->state = PHY_AN; + phydev->link_timeout = PHY_AN_TIMEOUT; + } + } else + phydev->state = PHY_RUNNING; + break; + } + + spin_unlock(&phydev->lock); + + if (needs_aneg) + err = phy_start_aneg(phydev); + + if (err < 0) + phy_error(phydev); + + mod_timer(&phydev->phy_timer, jiffies + PHY_STATE_TIME * HZ); +} + +#endif /* CONFIG_PHYCONTROL */ |