linux_dsm_epyc7002/drivers/net/phy/phy-core.c
Andrew Lunn 9f239fe6a6 net: phy: Have __phy_modify return 0 on success
__phy_modify would return the old value of the register before it was
modified. Thus on success, it does not return 0, but a positive value.
Thus functions using phy_modify, which is a wrapper around
__phy_modify, can start returning > 0 on success, rather than 0. As a
result, breakage has been noticed in various places, where 0 was
assumed.

Code inspection does not find any current location where the return of
the old value is currently used. So have __phy_modify return 0 on
success. When there is a real need for the old value, either a new
accessor can be added, or an additional parameter passed.

Fixes: fea23fb591 ("net: phy: convert read-modify-write to phy_modify()")
Fixes: 2b74e5be17 ("net: phy: add phy_modify() accessor")
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Tested-by: Niklas Cassel <niklas.cassel@axis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-15 12:49:30 -05:00

530 lines
14 KiB
C

/*
* Core PHY library, taken from phy.c
*
* 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/export.h>
#include <linux/phy.h>
const char *phy_speed_to_str(int speed)
{
switch (speed) {
case SPEED_10:
return "10Mbps";
case SPEED_100:
return "100Mbps";
case SPEED_1000:
return "1Gbps";
case SPEED_2500:
return "2.5Gbps";
case SPEED_5000:
return "5Gbps";
case SPEED_10000:
return "10Gbps";
case SPEED_14000:
return "14Gbps";
case SPEED_20000:
return "20Gbps";
case SPEED_25000:
return "25Gbps";
case SPEED_40000:
return "40Gbps";
case SPEED_50000:
return "50Gbps";
case SPEED_56000:
return "56Gbps";
case SPEED_100000:
return "100Gbps";
case SPEED_UNKNOWN:
return "Unknown";
default:
return "Unsupported (update phy-core.c)";
}
}
EXPORT_SYMBOL_GPL(phy_speed_to_str);
const char *phy_duplex_to_str(unsigned int duplex)
{
if (duplex == DUPLEX_HALF)
return "Half";
if (duplex == DUPLEX_FULL)
return "Full";
if (duplex == DUPLEX_UNKNOWN)
return "Unknown";
return "Unsupported (update phy-core.c)";
}
EXPORT_SYMBOL_GPL(phy_duplex_to_str);
/* A mapping of all SUPPORTED settings to speed/duplex. This table
* must be grouped by speed and sorted in descending match priority
* - iow, descending speed. */
static const struct phy_setting settings[] = {
{
.speed = SPEED_10000,
.duplex = DUPLEX_FULL,
.bit = ETHTOOL_LINK_MODE_10000baseKR_Full_BIT,
},
{
.speed = SPEED_10000,
.duplex = DUPLEX_FULL,
.bit = ETHTOOL_LINK_MODE_10000baseKX4_Full_BIT,
},
{
.speed = SPEED_10000,
.duplex = DUPLEX_FULL,
.bit = ETHTOOL_LINK_MODE_10000baseT_Full_BIT,
},
{
.speed = SPEED_2500,
.duplex = DUPLEX_FULL,
.bit = ETHTOOL_LINK_MODE_2500baseX_Full_BIT,
},
{
.speed = SPEED_1000,
.duplex = DUPLEX_FULL,
.bit = ETHTOOL_LINK_MODE_1000baseKX_Full_BIT,
},
{
.speed = SPEED_1000,
.duplex = DUPLEX_FULL,
.bit = ETHTOOL_LINK_MODE_1000baseX_Full_BIT,
},
{
.speed = SPEED_1000,
.duplex = DUPLEX_FULL,
.bit = ETHTOOL_LINK_MODE_1000baseT_Full_BIT,
},
{
.speed = SPEED_1000,
.duplex = DUPLEX_HALF,
.bit = ETHTOOL_LINK_MODE_1000baseT_Half_BIT,
},
{
.speed = SPEED_100,
.duplex = DUPLEX_FULL,
.bit = ETHTOOL_LINK_MODE_100baseT_Full_BIT,
},
{
.speed = SPEED_100,
.duplex = DUPLEX_HALF,
.bit = ETHTOOL_LINK_MODE_100baseT_Half_BIT,
},
{
.speed = SPEED_10,
.duplex = DUPLEX_FULL,
.bit = ETHTOOL_LINK_MODE_10baseT_Full_BIT,
},
{
.speed = SPEED_10,
.duplex = DUPLEX_HALF,
.bit = ETHTOOL_LINK_MODE_10baseT_Half_BIT,
},
};
/**
* phy_lookup_setting - lookup a PHY setting
* @speed: speed to match
* @duplex: duplex to match
* @mask: allowed link modes
* @maxbit: bit size of link modes
* @exact: an exact match is required
*
* Search the settings array for a setting that matches the speed and
* duplex, and which is supported.
*
* If @exact is unset, either an exact match or %NULL for no match will
* be returned.
*
* If @exact is set, an exact match, the fastest supported setting at
* or below the specified speed, the slowest supported setting, or if
* they all fail, %NULL will be returned.
*/
const struct phy_setting *
phy_lookup_setting(int speed, int duplex, const unsigned long *mask,
size_t maxbit, bool exact)
{
const struct phy_setting *p, *match = NULL, *last = NULL;
int i;
for (i = 0, p = settings; i < ARRAY_SIZE(settings); i++, p++) {
if (p->bit < maxbit && test_bit(p->bit, mask)) {
last = p;
if (p->speed == speed && p->duplex == duplex) {
/* Exact match for speed and duplex */
match = p;
break;
} else if (!exact) {
if (!match && p->speed <= speed)
/* Candidate */
match = p;
if (p->speed < speed)
break;
}
}
}
if (!match && !exact)
match = last;
return match;
}
EXPORT_SYMBOL_GPL(phy_lookup_setting);
size_t phy_speeds(unsigned int *speeds, size_t size,
unsigned long *mask, size_t maxbit)
{
size_t count;
int i;
for (i = 0, count = 0; i < ARRAY_SIZE(settings) && count < size; i++)
if (settings[i].bit < maxbit &&
test_bit(settings[i].bit, mask) &&
(count == 0 || speeds[count - 1] != settings[i].speed))
speeds[count++] = settings[i].speed;
return count;
}
/**
* phy_resolve_aneg_linkmode - resolve the advertisments into phy settings
* @phydev: The phy_device struct
*
* Resolve our and the link partner advertisments into their corresponding
* speed and duplex. If full duplex was negotiated, extract the pause mode
* from the link partner mask.
*/
void phy_resolve_aneg_linkmode(struct phy_device *phydev)
{
u32 common = phydev->lp_advertising & phydev->advertising;
if (common & ADVERTISED_10000baseT_Full) {
phydev->speed = SPEED_10000;
phydev->duplex = DUPLEX_FULL;
} else if (common & ADVERTISED_1000baseT_Full) {
phydev->speed = SPEED_1000;
phydev->duplex = DUPLEX_FULL;
} else if (common & ADVERTISED_1000baseT_Half) {
phydev->speed = SPEED_1000;
phydev->duplex = DUPLEX_HALF;
} else if (common & ADVERTISED_100baseT_Full) {
phydev->speed = SPEED_100;
phydev->duplex = DUPLEX_FULL;
} else if (common & ADVERTISED_100baseT_Half) {
phydev->speed = SPEED_100;
phydev->duplex = DUPLEX_HALF;
} else if (common & ADVERTISED_10baseT_Full) {
phydev->speed = SPEED_10;
phydev->duplex = DUPLEX_FULL;
} else if (common & ADVERTISED_10baseT_Half) {
phydev->speed = SPEED_10;
phydev->duplex = DUPLEX_HALF;
}
if (phydev->duplex == DUPLEX_FULL) {
phydev->pause = !!(phydev->lp_advertising & ADVERTISED_Pause);
phydev->asym_pause = !!(phydev->lp_advertising &
ADVERTISED_Asym_Pause);
}
}
EXPORT_SYMBOL_GPL(phy_resolve_aneg_linkmode);
static void mmd_phy_indirect(struct mii_bus *bus, int phy_addr, int devad,
u16 regnum)
{
/* Write the desired MMD Devad */
__mdiobus_write(bus, phy_addr, MII_MMD_CTRL, devad);
/* Write the desired MMD register address */
__mdiobus_write(bus, phy_addr, MII_MMD_DATA, regnum);
/* Select the Function : DATA with no post increment */
__mdiobus_write(bus, phy_addr, MII_MMD_CTRL,
devad | MII_MMD_CTRL_NOINCR);
}
/**
* phy_read_mmd - Convenience function for reading a register
* from an MMD on a given PHY.
* @phydev: The phy_device struct
* @devad: The MMD to read from (0..31)
* @regnum: The register on the MMD to read (0..65535)
*
* Same rules as for phy_read();
*/
int phy_read_mmd(struct phy_device *phydev, int devad, u32 regnum)
{
int val;
if (regnum > (u16)~0 || devad > 32)
return -EINVAL;
if (phydev->drv->read_mmd) {
val = phydev->drv->read_mmd(phydev, devad, regnum);
} else if (phydev->is_c45) {
u32 addr = MII_ADDR_C45 | (devad << 16) | (regnum & 0xffff);
val = mdiobus_read(phydev->mdio.bus, phydev->mdio.addr, addr);
} else {
struct mii_bus *bus = phydev->mdio.bus;
int phy_addr = phydev->mdio.addr;
mutex_lock(&bus->mdio_lock);
mmd_phy_indirect(bus, phy_addr, devad, regnum);
/* Read the content of the MMD's selected register */
val = __mdiobus_read(bus, phy_addr, MII_MMD_DATA);
mutex_unlock(&bus->mdio_lock);
}
return val;
}
EXPORT_SYMBOL(phy_read_mmd);
/**
* phy_write_mmd - Convenience function for writing a register
* on an MMD on a given PHY.
* @phydev: The phy_device struct
* @devad: The MMD to read from
* @regnum: The register on the MMD to read
* @val: value to write to @regnum
*
* Same rules as for phy_write();
*/
int phy_write_mmd(struct phy_device *phydev, int devad, u32 regnum, u16 val)
{
int ret;
if (regnum > (u16)~0 || devad > 32)
return -EINVAL;
if (phydev->drv->write_mmd) {
ret = phydev->drv->write_mmd(phydev, devad, regnum, val);
} else if (phydev->is_c45) {
u32 addr = MII_ADDR_C45 | (devad << 16) | (regnum & 0xffff);
ret = mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
addr, val);
} else {
struct mii_bus *bus = phydev->mdio.bus;
int phy_addr = phydev->mdio.addr;
mutex_lock(&bus->mdio_lock);
mmd_phy_indirect(bus, phy_addr, devad, regnum);
/* Write the data into MMD's selected register */
__mdiobus_write(bus, phy_addr, MII_MMD_DATA, val);
mutex_unlock(&bus->mdio_lock);
ret = 0;
}
return ret;
}
EXPORT_SYMBOL(phy_write_mmd);
/**
* __phy_modify() - Convenience function for modifying a PHY register
* @phydev: a pointer to a &struct phy_device
* @regnum: register number
* @mask: bit mask of bits to clear
* @set: bit mask of bits to set
*
* Unlocked helper function which allows a PHY register to be modified as
* new register value = (old register value & ~mask) | set
*/
int __phy_modify(struct phy_device *phydev, u32 regnum, u16 mask, u16 set)
{
int ret;
ret = __phy_read(phydev, regnum);
if (ret < 0)
return ret;
ret = __phy_write(phydev, regnum, (ret & ~mask) | set);
return ret < 0 ? ret : 0;
}
EXPORT_SYMBOL_GPL(__phy_modify);
/**
* phy_modify - Convenience function for modifying a given PHY register
* @phydev: the phy_device struct
* @regnum: register number to write
* @mask: bit mask of bits to clear
* @set: new value of bits set in mask to write to @regnum
*
* NOTE: MUST NOT be called from interrupt context,
* because the bus read/write functions may wait for an interrupt
* to conclude the operation.
*/
int phy_modify(struct phy_device *phydev, u32 regnum, u16 mask, u16 set)
{
int ret;
mutex_lock(&phydev->mdio.bus->mdio_lock);
ret = __phy_modify(phydev, regnum, mask, set);
mutex_unlock(&phydev->mdio.bus->mdio_lock);
return ret;
}
EXPORT_SYMBOL_GPL(phy_modify);
static int __phy_read_page(struct phy_device *phydev)
{
return phydev->drv->read_page(phydev);
}
static int __phy_write_page(struct phy_device *phydev, int page)
{
return phydev->drv->write_page(phydev, page);
}
/**
* phy_save_page() - take the bus lock and save the current page
* @phydev: a pointer to a &struct phy_device
*
* Take the MDIO bus lock, and return the current page number. On error,
* returns a negative errno. phy_restore_page() must always be called
* after this, irrespective of success or failure of this call.
*/
int phy_save_page(struct phy_device *phydev)
{
mutex_lock(&phydev->mdio.bus->mdio_lock);
return __phy_read_page(phydev);
}
EXPORT_SYMBOL_GPL(phy_save_page);
/**
* phy_select_page() - take the bus lock, save the current page, and set a page
* @phydev: a pointer to a &struct phy_device
* @page: desired page
*
* Take the MDIO bus lock to protect against concurrent access, save the
* current PHY page, and set the current page. On error, returns a
* negative errno, otherwise returns the previous page number.
* phy_restore_page() must always be called after this, irrespective
* of success or failure of this call.
*/
int phy_select_page(struct phy_device *phydev, int page)
{
int ret, oldpage;
oldpage = ret = phy_save_page(phydev);
if (ret < 0)
return ret;
if (oldpage != page) {
ret = __phy_write_page(phydev, page);
if (ret < 0)
return ret;
}
return oldpage;
}
EXPORT_SYMBOL_GPL(phy_select_page);
/**
* phy_restore_page() - restore the page register and release the bus lock
* @phydev: a pointer to a &struct phy_device
* @oldpage: the old page, return value from phy_save_page() or phy_select_page()
* @ret: operation's return code
*
* Release the MDIO bus lock, restoring @oldpage if it is a valid page.
* This function propagates the earliest error code from the group of
* operations.
*
* Returns:
* @oldpage if it was a negative value, otherwise
* @ret if it was a negative errno value, otherwise
* phy_write_page()'s negative value if it were in error, otherwise
* @ret.
*/
int phy_restore_page(struct phy_device *phydev, int oldpage, int ret)
{
int r;
if (oldpage >= 0) {
r = __phy_write_page(phydev, oldpage);
/* Propagate the operation return code if the page write
* was successful.
*/
if (ret >= 0 && r < 0)
ret = r;
} else {
/* Propagate the phy page selection error code */
ret = oldpage;
}
mutex_unlock(&phydev->mdio.bus->mdio_lock);
return ret;
}
EXPORT_SYMBOL_GPL(phy_restore_page);
/**
* phy_read_paged() - Convenience function for reading a paged register
* @phydev: a pointer to a &struct phy_device
* @page: the page for the phy
* @regnum: register number
*
* Same rules as for phy_read().
*/
int phy_read_paged(struct phy_device *phydev, int page, u32 regnum)
{
int ret = 0, oldpage;
oldpage = phy_select_page(phydev, page);
if (oldpage >= 0)
ret = __phy_read(phydev, regnum);
return phy_restore_page(phydev, oldpage, ret);
}
EXPORT_SYMBOL(phy_read_paged);
/**
* phy_write_paged() - Convenience function for writing a paged register
* @phydev: a pointer to a &struct phy_device
* @page: the page for the phy
* @regnum: register number
* @val: value to write
*
* Same rules as for phy_write().
*/
int phy_write_paged(struct phy_device *phydev, int page, u32 regnum, u16 val)
{
int ret = 0, oldpage;
oldpage = phy_select_page(phydev, page);
if (oldpage >= 0)
ret = __phy_write(phydev, regnum, val);
return phy_restore_page(phydev, oldpage, ret);
}
EXPORT_SYMBOL(phy_write_paged);
/**
* phy_modify_paged() - Convenience function for modifying a paged register
* @phydev: a pointer to a &struct phy_device
* @page: the page for the phy
* @regnum: register number
* @mask: bit mask of bits to clear
* @set: bit mask of bits to set
*
* Same rules as for phy_read() and phy_write().
*/
int phy_modify_paged(struct phy_device *phydev, int page, u32 regnum,
u16 mask, u16 set)
{
int ret = 0, oldpage;
oldpage = phy_select_page(phydev, page);
if (oldpage >= 0)
ret = __phy_modify(phydev, regnum, mask, set);
return phy_restore_page(phydev, oldpage, ret);
}
EXPORT_SYMBOL(phy_modify_paged);