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author | Michael Walle <michael@walle.cc> | 2020-05-13 19:35:23 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2020-05-13 22:52:38 +0300 |
commit | 11ecf8c55b91806e4dc6a1b9fe7cbf68cdc9b006 (patch) | |
tree | 8dad14749b9bfdbf39a45ef1560beada87d66515 /drivers/net/phy/bcm-phy-lib.c | |
parent | e184a9072f8995e78ad6cef48bfeab2b987945ec (diff) | |
download | linux-11ecf8c55b91806e4dc6a1b9fe7cbf68cdc9b006.tar.xz |
net: phy: broadcom: add cable test support
Most modern broadcom PHYs support ECD (enhanced cable diagnostics). Add
support for it in the bcm-phy-lib so they can easily be used in the PHY
driver.
There are two access methods for ECD: legacy by expansion registers and
via the new RDB registers which are exclusive. Provide functions in two
variants where the PHY driver can choose from. To keep things simple for
now, we just switch the register access to expansion registers in the
RDB variant for now. On the flipside, we have to keep a bus lock to
prevent any other non-legacy access on the PHY.
The results of the intra-pair tests are inconclusive (at least for the
BCM54140). Most of the times half the length is reported but sometimes
the length is correct.
Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/phy/bcm-phy-lib.c')
-rw-r--r-- | drivers/net/phy/bcm-phy-lib.c | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/drivers/net/phy/bcm-phy-lib.c b/drivers/net/phy/bcm-phy-lib.c index 41c728fbcfb2..cb92786e3ded 100644 --- a/drivers/net/phy/bcm-phy-lib.c +++ b/drivers/net/phy/bcm-phy-lib.c @@ -4,12 +4,14 @@ */ #include "bcm-phy-lib.h" +#include <linux/bitfield.h> #include <linux/brcmphy.h> #include <linux/export.h> #include <linux/mdio.h> #include <linux/module.h> #include <linux/phy.h> #include <linux/ethtool.h> +#include <linux/ethtool_netlink.h> #define MII_BCM_CHANNEL_WIDTH 0x2000 #define BCM_CL45VEN_EEE_ADV 0x3c @@ -581,6 +583,193 @@ int bcm_phy_enable_jumbo(struct phy_device *phydev) } EXPORT_SYMBOL_GPL(bcm_phy_enable_jumbo); +int __bcm_phy_enable_rdb_access(struct phy_device *phydev) +{ + return __bcm_phy_write_exp(phydev, BCM54XX_EXP_REG7E, 0); +} +EXPORT_SYMBOL_GPL(__bcm_phy_enable_rdb_access); + +int __bcm_phy_enable_legacy_access(struct phy_device *phydev) +{ + return __bcm_phy_write_rdb(phydev, BCM54XX_RDB_REG0087, + BCM54XX_ACCESS_MODE_LEGACY_EN); +} +EXPORT_SYMBOL_GPL(__bcm_phy_enable_legacy_access); + +static int _bcm_phy_cable_test_start(struct phy_device *phydev, bool is_rdb) +{ + u16 mask, set; + int ret; + + /* Auto-negotiation must be enabled for cable diagnostics to work, but + * don't advertise any capabilities. + */ + phy_write(phydev, MII_BMCR, BMCR_ANENABLE); + phy_write(phydev, MII_ADVERTISE, ADVERTISE_CSMA); + phy_write(phydev, MII_CTRL1000, 0); + + phy_lock_mdio_bus(phydev); + if (is_rdb) { + ret = __bcm_phy_enable_legacy_access(phydev); + if (ret) + goto out; + } + + mask = BCM54XX_ECD_CTRL_CROSS_SHORT_DIS | BCM54XX_ECD_CTRL_UNIT_MASK; + set = BCM54XX_ECD_CTRL_RUN | BCM54XX_ECD_CTRL_BREAK_LINK | + FIELD_PREP(BCM54XX_ECD_CTRL_UNIT_MASK, + BCM54XX_ECD_CTRL_UNIT_CM); + + ret = __bcm_phy_modify_exp(phydev, BCM54XX_EXP_ECD_CTRL, mask, set); + +out: + /* re-enable the RDB access even if there was an error */ + if (is_rdb) + ret = __bcm_phy_enable_rdb_access(phydev) ? : ret; + + phy_unlock_mdio_bus(phydev); + + return ret; +} + +static int bcm_phy_cable_test_report_trans(int result) +{ + switch (result) { + case BCM54XX_ECD_FAULT_TYPE_OK: + return ETHTOOL_A_CABLE_RESULT_CODE_OK; + case BCM54XX_ECD_FAULT_TYPE_OPEN: + return ETHTOOL_A_CABLE_RESULT_CODE_OPEN; + case BCM54XX_ECD_FAULT_TYPE_SAME_SHORT: + return ETHTOOL_A_CABLE_RESULT_CODE_SAME_SHORT; + case BCM54XX_ECD_FAULT_TYPE_CROSS_SHORT: + return ETHTOOL_A_CABLE_RESULT_CODE_CROSS_SHORT; + case BCM54XX_ECD_FAULT_TYPE_INVALID: + case BCM54XX_ECD_FAULT_TYPE_BUSY: + default: + return ETHTOOL_A_CABLE_RESULT_CODE_UNSPEC; + } +} + +static bool bcm_phy_distance_valid(int result) +{ + switch (result) { + case BCM54XX_ECD_FAULT_TYPE_OPEN: + case BCM54XX_ECD_FAULT_TYPE_SAME_SHORT: + case BCM54XX_ECD_FAULT_TYPE_CROSS_SHORT: + return true; + } + return false; +} + +static int bcm_phy_report_length(struct phy_device *phydev, int pair) +{ + int val; + + val = __bcm_phy_read_exp(phydev, + BCM54XX_EXP_ECD_PAIR_A_LENGTH_RESULTS + pair); + if (val < 0) + return val; + + if (val == BCM54XX_ECD_LENGTH_RESULTS_INVALID) + return 0; + + ethnl_cable_test_fault_length(phydev, pair, val); + + return 0; +} + +static int _bcm_phy_cable_test_get_status(struct phy_device *phydev, + bool *finished, bool is_rdb) +{ + int pair_a, pair_b, pair_c, pair_d, ret; + + *finished = false; + + phy_lock_mdio_bus(phydev); + + if (is_rdb) { + ret = __bcm_phy_enable_legacy_access(phydev); + if (ret) + goto out; + } + + ret = __bcm_phy_read_exp(phydev, BCM54XX_EXP_ECD_CTRL); + if (ret < 0) + goto out; + + if (ret & BCM54XX_ECD_CTRL_IN_PROGRESS) { + ret = 0; + goto out; + } + + ret = __bcm_phy_read_exp(phydev, BCM54XX_EXP_ECD_FAULT_TYPE); + if (ret < 0) + goto out; + + pair_a = FIELD_GET(BCM54XX_ECD_FAULT_TYPE_PAIR_A_MASK, ret); + pair_b = FIELD_GET(BCM54XX_ECD_FAULT_TYPE_PAIR_B_MASK, ret); + pair_c = FIELD_GET(BCM54XX_ECD_FAULT_TYPE_PAIR_C_MASK, ret); + pair_d = FIELD_GET(BCM54XX_ECD_FAULT_TYPE_PAIR_D_MASK, ret); + + ethnl_cable_test_result(phydev, ETHTOOL_A_CABLE_PAIR_A, + bcm_phy_cable_test_report_trans(pair_a)); + ethnl_cable_test_result(phydev, ETHTOOL_A_CABLE_PAIR_B, + bcm_phy_cable_test_report_trans(pair_b)); + ethnl_cable_test_result(phydev, ETHTOOL_A_CABLE_PAIR_C, + bcm_phy_cable_test_report_trans(pair_c)); + ethnl_cable_test_result(phydev, ETHTOOL_A_CABLE_PAIR_D, + bcm_phy_cable_test_report_trans(pair_d)); + + if (bcm_phy_distance_valid(pair_a)) + bcm_phy_report_length(phydev, 0); + if (bcm_phy_distance_valid(pair_b)) + bcm_phy_report_length(phydev, 1); + if (bcm_phy_distance_valid(pair_c)) + bcm_phy_report_length(phydev, 2); + if (bcm_phy_distance_valid(pair_d)) + bcm_phy_report_length(phydev, 3); + + ret = 0; + *finished = true; +out: + /* re-enable the RDB access even if there was an error */ + if (is_rdb) + ret = __bcm_phy_enable_rdb_access(phydev) ? : ret; + + phy_unlock_mdio_bus(phydev); + + return ret; +} + +int bcm_phy_cable_test_start(struct phy_device *phydev) +{ + return _bcm_phy_cable_test_start(phydev, false); +} +EXPORT_SYMBOL_GPL(bcm_phy_cable_test_start); + +int bcm_phy_cable_test_get_status(struct phy_device *phydev, bool *finished) +{ + return _bcm_phy_cable_test_get_status(phydev, finished, false); +} +EXPORT_SYMBOL_GPL(bcm_phy_cable_test_get_status); + +/* We assume that all PHYs which support RDB access can be switched to legacy + * mode. If, in the future, this is not true anymore, we have to re-implement + * this with RDB access. + */ +int bcm_phy_cable_test_start_rdb(struct phy_device *phydev) +{ + return _bcm_phy_cable_test_start(phydev, true); +} +EXPORT_SYMBOL_GPL(bcm_phy_cable_test_start_rdb); + +int bcm_phy_cable_test_get_status_rdb(struct phy_device *phydev, + bool *finished) +{ + return _bcm_phy_cable_test_get_status(phydev, finished, true); +} +EXPORT_SYMBOL_GPL(bcm_phy_cable_test_get_status_rdb); + MODULE_DESCRIPTION("Broadcom PHY Library"); MODULE_LICENSE("GPL v2"); MODULE_AUTHOR("Broadcom Corporation"); |