kernel-fxtec-pro1x/drivers/net/phy/phy.c
David Howells 7d12e780e0 IRQ: Maintain regs pointer globally rather than passing to IRQ handlers
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 15:10:12 +01:00

857 lines
19 KiB
C

/*
* 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/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/mii.h>
#include <linux/ethtool.h>
#include <linux/phy.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/uaccess.h>
/* Convenience function to print out the current phy status
*/
void phy_print_status(struct phy_device *phydev)
{
pr_info("PHY: %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);
}
/* 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 const 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_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_aneg
*
* description: Sanitizes the settings (if we're not
* autonegotiating them), and then calls the driver's
* config_aneg function. If the PHYCONTROL Layer is operating,
* we change the state to reflect the beginning of
* Auto-negotiation or forcing.
*/
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);
static void phy_change(void *data);
static void phy_timer(unsigned long data);
/* 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). 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);
phydev->adjust_state = NULL;
}
/* 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_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 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,
IRQF_SHARED,
"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);
}