diff options
Diffstat (limited to 'drivers/net/phy/at803x.c')
| -rw-r--r-- | drivers/net/phy/at803x.c | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/drivers/net/phy/at803x.c b/drivers/net/phy/at803x.c index f4fec5f644e9..acd51b29a476 100644 --- a/drivers/net/phy/at803x.c +++ b/drivers/net/phy/at803x.c @@ -12,6 +12,7 @@ #include <linux/string.h> #include <linux/netdevice.h> #include <linux/etherdevice.h> +#include <linux/ethtool_netlink.h> #include <linux/of_gpio.h> #include <linux/bitfield.h> #include <linux/gpio/consumer.h> @@ -46,6 +47,16 @@ #define AT803X_SMART_SPEED_ENABLE BIT(5) #define AT803X_SMART_SPEED_RETRY_LIMIT_MASK GENMASK(4, 2) #define AT803X_SMART_SPEED_BYPASS_TIMER BIT(1) +#define AT803X_CDT 0x16 +#define AT803X_CDT_MDI_PAIR_MASK GENMASK(9, 8) +#define AT803X_CDT_ENABLE_TEST BIT(0) +#define AT803X_CDT_STATUS 0x1c +#define AT803X_CDT_STATUS_STAT_NORMAL 0 +#define AT803X_CDT_STATUS_STAT_SHORT 1 +#define AT803X_CDT_STATUS_STAT_OPEN 2 +#define AT803X_CDT_STATUS_STAT_FAIL 3 +#define AT803X_CDT_STATUS_STAT_MASK GENMASK(9, 8) +#define AT803X_CDT_STATUS_DELTA_TIME_MASK GENMASK(7, 0) #define AT803X_LED_CONTROL 0x18 #define AT803X_DEVICE_ADDR 0x03 @@ -794,12 +805,172 @@ static int at803x_set_tunable(struct phy_device *phydev, } } +static int at803x_cable_test_result_trans(u16 status) +{ + switch (FIELD_GET(AT803X_CDT_STATUS_STAT_MASK, status)) { + case AT803X_CDT_STATUS_STAT_NORMAL: + return ETHTOOL_A_CABLE_RESULT_CODE_OK; + case AT803X_CDT_STATUS_STAT_SHORT: + return ETHTOOL_A_CABLE_RESULT_CODE_SAME_SHORT; + case AT803X_CDT_STATUS_STAT_OPEN: + return ETHTOOL_A_CABLE_RESULT_CODE_OPEN; + case AT803X_CDT_STATUS_STAT_FAIL: + default: + return ETHTOOL_A_CABLE_RESULT_CODE_UNSPEC; + } +} + +static bool at803x_cdt_test_failed(u16 status) +{ + return FIELD_GET(AT803X_CDT_STATUS_STAT_MASK, status) == + AT803X_CDT_STATUS_STAT_FAIL; +} + +static bool at803x_cdt_fault_length_valid(u16 status) +{ + switch (FIELD_GET(AT803X_CDT_STATUS_STAT_MASK, status)) { + case AT803X_CDT_STATUS_STAT_OPEN: + case AT803X_CDT_STATUS_STAT_SHORT: + return true; + } + return false; +} + +static int at803x_cdt_fault_length(u16 status) +{ + int dt; + + /* According to the datasheet the distance to the fault is + * DELTA_TIME * 0.824 meters. + * + * The author suspect the correct formula is: + * + * fault_distance = DELTA_TIME * (c * VF) / 125MHz / 2 + * + * where c is the speed of light, VF is the velocity factor of + * the twisted pair cable, 125MHz the counter frequency and + * we need to divide by 2 because the hardware will measure the + * round trip time to the fault and back to the PHY. + * + * With a VF of 0.69 we get the factor 0.824 mentioned in the + * datasheet. + */ + dt = FIELD_GET(AT803X_CDT_STATUS_DELTA_TIME_MASK, status); + + return (dt * 824) / 10; +} + +static int at803x_cdt_start(struct phy_device *phydev, int pair) +{ + u16 cdt; + + cdt = FIELD_PREP(AT803X_CDT_MDI_PAIR_MASK, pair) | + AT803X_CDT_ENABLE_TEST; + + return phy_write(phydev, AT803X_CDT, cdt); +} + +static int at803x_cdt_wait_for_completion(struct phy_device *phydev) +{ + int val, ret; + + /* One test run takes about 25ms */ + ret = phy_read_poll_timeout(phydev, AT803X_CDT, val, + !(val & AT803X_CDT_ENABLE_TEST), + 30000, 100000, true); + + return ret < 0 ? ret : 0; +} + +static int at803x_cable_test_one_pair(struct phy_device *phydev, int pair) +{ + static const int ethtool_pair[] = { + ETHTOOL_A_CABLE_PAIR_A, + ETHTOOL_A_CABLE_PAIR_B, + ETHTOOL_A_CABLE_PAIR_C, + ETHTOOL_A_CABLE_PAIR_D, + }; + int ret, val; + + ret = at803x_cdt_start(phydev, pair); + if (ret) + return ret; + + ret = at803x_cdt_wait_for_completion(phydev); + if (ret) + return ret; + + val = phy_read(phydev, AT803X_CDT_STATUS); + if (val < 0) + return val; + + if (at803x_cdt_test_failed(val)) + return 0; + + ethnl_cable_test_result(phydev, ethtool_pair[pair], + at803x_cable_test_result_trans(val)); + + if (at803x_cdt_fault_length_valid(val)) + ethnl_cable_test_fault_length(phydev, ethtool_pair[pair], + at803x_cdt_fault_length(val)); + + return 1; +} + +static int at803x_cable_test_get_status(struct phy_device *phydev, + bool *finished) +{ + unsigned long pair_mask = 0xf; + int retries = 20; + int pair, ret; + + *finished = false; + + /* According to the datasheet the CDT can be performed when + * there is no link partner or when the link partner is + * auto-negotiating. Starting the test will restart the AN + * automatically. It seems that doing this repeatedly we will + * get a slot where our link partner won't disturb our + * measurement. + */ + while (pair_mask && retries--) { + for_each_set_bit(pair, &pair_mask, 4) { + ret = at803x_cable_test_one_pair(phydev, pair); + if (ret < 0) + return ret; + if (ret) + clear_bit(pair, &pair_mask); + } + if (pair_mask) + msleep(250); + } + + *finished = true; + + return 0; +} + +static int at803x_cable_test_start(struct phy_device *phydev) +{ + /* Enable auto-negotiation, but advertise no capabilities, no link + * will be established. A restart of the auto-negotiation is not + * required, because the cable test will automatically break the link. + */ + phy_write(phydev, MII_BMCR, BMCR_ANENABLE); + phy_write(phydev, MII_ADVERTISE, ADVERTISE_CSMA); + phy_write(phydev, MII_CTRL1000, 0); + + /* we do all the (time consuming) work later */ + return 0; +} + static struct phy_driver at803x_driver[] = { { /* Qualcomm Atheros AR8035 */ .phy_id = ATH8035_PHY_ID, .name = "Qualcomm Atheros AR8035", .phy_id_mask = AT803X_PHY_ID_MASK, + .flags = PHY_POLL_CABLE_TEST, .probe = at803x_probe, .remove = at803x_remove, .config_init = at803x_config_init, @@ -814,6 +985,8 @@ static struct phy_driver at803x_driver[] = { .config_intr = at803x_config_intr, .get_tunable = at803x_get_tunable, .set_tunable = at803x_set_tunable, + .cable_test_start = at803x_cable_test_start, + .cable_test_get_status = at803x_cable_test_get_status, }, { /* Qualcomm Atheros AR8030 */ .phy_id = ATH8030_PHY_ID, @@ -835,6 +1008,7 @@ static struct phy_driver at803x_driver[] = { .phy_id = ATH8031_PHY_ID, .name = "Qualcomm Atheros AR8031/AR8033", .phy_id_mask = AT803X_PHY_ID_MASK, + .flags = PHY_POLL_CABLE_TEST, .probe = at803x_probe, .remove = at803x_remove, .config_init = at803x_config_init, @@ -850,6 +1024,8 @@ static struct phy_driver at803x_driver[] = { .config_intr = &at803x_config_intr, .get_tunable = at803x_get_tunable, .set_tunable = at803x_set_tunable, + .cable_test_start = at803x_cable_test_start, + .cable_test_get_status = at803x_cable_test_get_status, }, { /* Qualcomm Atheros AR8032 */ PHY_ID_MATCH_EXACT(ATH8032_PHY_ID), |