diff options
Diffstat (limited to 'drivers/net/phy/dp83tg720.c')
| -rw-r--r-- | drivers/net/phy/dp83tg720.c | 431 |
1 files changed, 427 insertions, 4 deletions
diff --git a/drivers/net/phy/dp83tg720.c b/drivers/net/phy/dp83tg720.c index 326c9770a6dc..7e76323409c4 100644 --- a/drivers/net/phy/dp83tg720.c +++ b/drivers/net/phy/dp83tg720.c @@ -3,9 +3,31 @@ * Copyright (c) 2023 Pengutronix, Oleksij Rempel <kernel@pengutronix.de> */ #include <linux/bitfield.h> +#include <linux/ethtool_netlink.h> +#include <linux/jiffies.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/phy.h> +#include <linux/random.h> + +#include "open_alliance_helpers.h" + +/* + * DP83TG720S_POLL_ACTIVE_LINK - Polling interval in milliseconds when the link + * is active. + * DP83TG720S_POLL_NO_LINK_MIN - Minimum polling interval in milliseconds when + * the link is down. + * DP83TG720S_POLL_NO_LINK_MAX - Maximum polling interval in milliseconds when + * the link is down. + * + * These values are not documented or officially recommended by the vendor but + * were determined through empirical testing. They achieve a good balance in + * minimizing the number of reset retries while ensuring reliable link recovery + * within a reasonable timeframe. + */ +#define DP83TG720S_POLL_ACTIVE_LINK 1000 +#define DP83TG720S_POLL_NO_LINK_MIN 100 +#define DP83TG720S_POLL_NO_LINK_MAX 1000 #define DP83TG720S_PHY_ID 0x2000a284 @@ -14,28 +36,328 @@ #define DP83TG720S_STS_MII_INT BIT(7) #define DP83TG720S_LINK_STATUS BIT(0) +/* TDR Configuration Register (0x1E) */ +#define DP83TG720S_TDR_CFG 0x1e +/* 1b = TDR start, 0b = No TDR */ +#define DP83TG720S_TDR_START BIT(15) +/* 1b = TDR auto on link down, 0b = Manual TDR start */ +#define DP83TG720S_CFG_TDR_AUTO_RUN BIT(14) +/* 1b = TDR done, 0b = TDR in progress */ +#define DP83TG720S_TDR_DONE BIT(1) +/* 1b = TDR fail, 0b = TDR success */ +#define DP83TG720S_TDR_FAIL BIT(0) + #define DP83TG720S_PHY_RESET 0x1f #define DP83TG720S_HW_RESET BIT(15) +#define DP83TG720S_LPS_CFG3 0x18c +/* Power modes are documented as bit fields but used as values */ +/* Power Mode 0 is Normal mode */ +#define DP83TG720S_LPS_CFG3_PWR_MODE_0 BIT(0) + +/* Open Aliance 1000BaseT1 compatible HDD.TDR Fault Status Register */ +#define DP83TG720S_TDR_FAULT_STATUS 0x30f + +/* Register 0x0301: TDR Configuration 2 */ +#define DP83TG720S_TDR_CFG2 0x301 + +/* Register 0x0303: TDR Configuration 3 */ +#define DP83TG720S_TDR_CFG3 0x303 + +/* Register 0x0304: TDR Configuration 4 */ +#define DP83TG720S_TDR_CFG4 0x304 + +/* Register 0x0405: Unknown Register */ +#define DP83TG720S_UNKNOWN_0405 0x405 + +#define DP83TG720S_LINK_QUAL_3 0x547 +#define DP83TG720S_LINK_LOSS_CNT_MASK GENMASK(15, 10) + +/* Register 0x0576: TDR Master Link Down Control */ +#define DP83TG720S_TDR_MASTER_LINK_DOWN 0x576 + #define DP83TG720S_RGMII_DELAY_CTRL 0x602 /* In RGMII mode, Enable or disable the internal delay for RXD */ #define DP83TG720S_RGMII_RX_CLK_SEL BIT(1) /* In RGMII mode, Enable or disable the internal delay for TXD */ #define DP83TG720S_RGMII_TX_CLK_SEL BIT(0) +/* + * DP83TG720S_PKT_STAT_x registers correspond to similarly named registers + * in the datasheet (PKT_STAT_1 through PKT_STAT_6). These registers store + * 32-bit or 16-bit counters for TX and RX statistics and must be read in + * sequence to ensure the counters are cleared correctly. + * + * - DP83TG720S_PKT_STAT_1: Contains TX packet count bits [15:0]. + * - DP83TG720S_PKT_STAT_2: Contains TX packet count bits [31:16]. + * - DP83TG720S_PKT_STAT_3: Contains TX error packet count. + * - DP83TG720S_PKT_STAT_4: Contains RX packet count bits [15:0]. + * - DP83TG720S_PKT_STAT_5: Contains RX packet count bits [31:16]. + * - DP83TG720S_PKT_STAT_6: Contains RX error packet count. + * + * Keeping the register names as defined in the datasheet helps maintain + * clarity and alignment with the documentation. + */ +#define DP83TG720S_PKT_STAT_1 0x639 +#define DP83TG720S_PKT_STAT_2 0x63a +#define DP83TG720S_PKT_STAT_3 0x63b +#define DP83TG720S_PKT_STAT_4 0x63c +#define DP83TG720S_PKT_STAT_5 0x63d +#define DP83TG720S_PKT_STAT_6 0x63e + +/* Register 0x083F: Unknown Register */ +#define DP83TG720S_UNKNOWN_083F 0x83f + #define DP83TG720S_SQI_REG_1 0x871 #define DP83TG720S_SQI_OUT_WORST GENMASK(7, 5) #define DP83TG720S_SQI_OUT GENMASK(3, 1) #define DP83TG720_SQI_MAX 7 +struct dp83tg720_stats { + u64 link_loss_cnt; + u64 tx_pkt_cnt; + u64 tx_err_pkt_cnt; + u64 rx_pkt_cnt; + u64 rx_err_pkt_cnt; +}; + +struct dp83tg720_priv { + struct dp83tg720_stats stats; +}; + +/** + * dp83tg720_update_stats - Update the PHY statistics for the DP83TD510 PHY. + * @phydev: Pointer to the phy_device structure. + * + * The function reads the PHY statistics registers and updates the statistics + * structure. + * + * Returns: 0 on success or a negative error code on failure. + */ +static int dp83tg720_update_stats(struct phy_device *phydev) +{ + struct dp83tg720_priv *priv = phydev->priv; + u32 count; + int ret; + + /* Read the link loss count */ + ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_LINK_QUAL_3); + if (ret < 0) + return ret; + /* link_loss_cnt */ + count = FIELD_GET(DP83TG720S_LINK_LOSS_CNT_MASK, ret); + priv->stats.link_loss_cnt += count; + + /* The DP83TG720S_PKT_STAT registers are divided into two groups: + * - Group 1 (TX stats): DP83TG720S_PKT_STAT_1 to DP83TG720S_PKT_STAT_3 + * - Group 2 (RX stats): DP83TG720S_PKT_STAT_4 to DP83TG720S_PKT_STAT_6 + * + * Registers in each group are cleared only after reading them in a + * plain sequence (e.g., 1, 2, 3 for Group 1 or 4, 5, 6 for Group 2). + * Any deviation from the sequence, such as reading 1, 2, 1, 2, 3, will + * prevent the group from being cleared. Additionally, the counters + * for a group are frozen as soon as the first register in that group + * is accessed. + */ + ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_PKT_STAT_1); + if (ret < 0) + return ret; + /* tx_pkt_cnt_15_0 */ + count = ret; + + ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_PKT_STAT_2); + if (ret < 0) + return ret; + /* tx_pkt_cnt_31_16 */ + count |= ret << 16; + priv->stats.tx_pkt_cnt += count; + + ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_PKT_STAT_3); + if (ret < 0) + return ret; + /* tx_err_pkt_cnt */ + priv->stats.tx_err_pkt_cnt += ret; + + ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_PKT_STAT_4); + if (ret < 0) + return ret; + /* rx_pkt_cnt_15_0 */ + count = ret; + + ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_PKT_STAT_5); + if (ret < 0) + return ret; + /* rx_pkt_cnt_31_16 */ + count |= ret << 16; + priv->stats.rx_pkt_cnt += count; + + ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_PKT_STAT_6); + if (ret < 0) + return ret; + /* rx_err_pkt_cnt */ + priv->stats.rx_err_pkt_cnt += ret; + + return 0; +} + +static void dp83tg720_get_link_stats(struct phy_device *phydev, + struct ethtool_link_ext_stats *link_stats) +{ + struct dp83tg720_priv *priv = phydev->priv; + + link_stats->link_down_events = priv->stats.link_loss_cnt; +} + +static void dp83tg720_get_phy_stats(struct phy_device *phydev, + struct ethtool_eth_phy_stats *eth_stats, + struct ethtool_phy_stats *stats) +{ + struct dp83tg720_priv *priv = phydev->priv; + + stats->tx_packets = priv->stats.tx_pkt_cnt; + stats->tx_errors = priv->stats.tx_err_pkt_cnt; + stats->rx_packets = priv->stats.rx_pkt_cnt; + stats->rx_errors = priv->stats.rx_err_pkt_cnt; +} + +/** + * dp83tg720_cable_test_start - Start the cable test for the DP83TG720 PHY. + * @phydev: Pointer to the phy_device structure. + * + * This sequence is based on the documented procedure for the DP83TG720 PHY. + * + * Returns: 0 on success, a negative error code on failure. + */ +static int dp83tg720_cable_test_start(struct phy_device *phydev) +{ + int ret; + + /* Initialize the PHY to run the TDR test as described in the + * "DP83TG720S-Q1: Configuring for Open Alliance Specification + * Compliance (Rev. B)" application note. + * Most of the registers are not documented. Some of register names + * are guessed by comparing the register offsets with the DP83TD510E. + */ + + /* Force master link down */ + ret = phy_set_bits_mmd(phydev, MDIO_MMD_VEND2, + DP83TG720S_TDR_MASTER_LINK_DOWN, 0x0400); + if (ret) + return ret; + + ret = phy_write_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_TDR_CFG2, + 0xa008); + if (ret) + return ret; + + ret = phy_write_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_TDR_CFG3, + 0x0928); + if (ret) + return ret; + + ret = phy_write_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_TDR_CFG4, + 0x0004); + if (ret) + return ret; + + ret = phy_write_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_UNKNOWN_0405, + 0x6400); + if (ret) + return ret; + + ret = phy_write_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_UNKNOWN_083F, + 0x3003); + if (ret) + return ret; + + /* Start the TDR */ + ret = phy_set_bits_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_TDR_CFG, + DP83TG720S_TDR_START); + if (ret) + return ret; + + return 0; +} + +/** + * dp83tg720_cable_test_get_status - Get the status of the cable test for the + * DP83TG720 PHY. + * @phydev: Pointer to the phy_device structure. + * @finished: Pointer to a boolean that indicates whether the test is finished. + * + * The function sets the @finished flag to true if the test is complete. + * + * Returns: 0 on success or a negative error code on failure. + */ +static int dp83tg720_cable_test_get_status(struct phy_device *phydev, + bool *finished) +{ + int ret, stat; + + *finished = false; + + /* Read the TDR status */ + ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_TDR_CFG); + if (ret < 0) + return ret; + + /* Check if the TDR test is done */ + if (!(ret & DP83TG720S_TDR_DONE)) + return 0; + + /* Check for TDR test failure */ + if (!(ret & DP83TG720S_TDR_FAIL)) { + int location; + + /* Read fault status */ + ret = phy_read_mmd(phydev, MDIO_MMD_VEND2, + DP83TG720S_TDR_FAULT_STATUS); + if (ret < 0) + return ret; + + /* Get fault type */ + stat = oa_1000bt1_get_ethtool_cable_result_code(ret); + + /* Determine fault location */ + location = oa_1000bt1_get_tdr_distance(ret); + if (location > 0) + ethnl_cable_test_fault_length(phydev, + ETHTOOL_A_CABLE_PAIR_A, + location); + } else { + /* Active link partner or other issues */ + stat = ETHTOOL_A_CABLE_RESULT_CODE_UNSPEC; + } + + *finished = true; + + ethnl_cable_test_result(phydev, ETHTOOL_A_CABLE_PAIR_A, stat); + + /* save the current stats before resetting the PHY */ + ret = dp83tg720_update_stats(phydev); + if (ret) + return ret; + + return phy_init_hw(phydev); +} + static int dp83tg720_config_aneg(struct phy_device *phydev) { + int ret; + /* Autoneg is not supported and this PHY supports only one speed. * We need to care only about master/slave configuration if it was * changed by user. */ - return genphy_c45_pma_baset1_setup_master_slave(phydev); + ret = genphy_c45_pma_baset1_setup_master_slave(phydev); + if (ret) + return ret; + + /* Re-read role configuration to make changes visible even if + * the link is in administrative down state. + */ + return genphy_c45_pma_baset1_read_master_slave(phydev); } static int dp83tg720_read_status(struct phy_device *phydev) @@ -52,6 +374,11 @@ static int dp83tg720_read_status(struct phy_device *phydev) phy_sts = phy_read(phydev, DP83TG720S_MII_REG_10); phydev->link = !!(phy_sts & DP83TG720S_LINK_STATUS); if (!phydev->link) { + /* save the current stats before resetting the PHY */ + ret = dp83tg720_update_stats(phydev); + if (ret) + return ret; + /* According to the "DP83TC81x, DP83TG72x Software * Implementation Guide", the PHY needs to be reset after a * link loss or if no link is created after at least 100ms. @@ -63,7 +390,16 @@ static int dp83tg720_read_status(struct phy_device *phydev) if (ret) return ret; + /* Sleep 600ms for PHY stabilization post-reset. + * Empirically chosen value (not documented). + * Helps reduce reset bounces with link partners having similar + * issues. + */ + msleep(600); + /* After HW reset we need to restore master/slave configuration. + * genphy_c45_pma_baset1_read_master_slave() call will be done + * by the dp83tg720_config_aneg() function. */ ret = dp83tg720_config_aneg(phydev); if (ret) @@ -154,30 +490,117 @@ static int dp83tg720_config_init(struct phy_device *phydev) */ usleep_range(1000, 2000); - if (phy_interface_is_rgmii(phydev)) - return dp83tg720_config_rgmii_delay(phydev); + if (phy_interface_is_rgmii(phydev)) { + ret = dp83tg720_config_rgmii_delay(phydev); + if (ret) + return ret; + } + + /* In case the PHY is bootstrapped in managed mode, we need to + * wake it. + */ + ret = phy_write_mmd(phydev, MDIO_MMD_VEND2, DP83TG720S_LPS_CFG3, + DP83TG720S_LPS_CFG3_PWR_MODE_0); + if (ret) + return ret; + + /* Make role configuration visible for ethtool on init and after + * rest. + */ + return genphy_c45_pma_baset1_read_master_slave(phydev); +} + +static int dp83tg720_probe(struct phy_device *phydev) +{ + struct device *dev = &phydev->mdio.dev; + struct dp83tg720_priv *priv; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + phydev->priv = priv; return 0; } +/** + * dp83tg720_get_next_update_time - Determine the next update time for PHY + * state + * @phydev: Pointer to the phy_device structure + * + * This function addresses a limitation of the DP83TG720 PHY, which cannot + * reliably detect or report a stable link state. To recover from such + * scenarios, the PHY must be periodically reset when the link is down. However, + * if the link partner also runs Linux with the same driver, synchronized reset + * intervals can lead to a deadlock where the link never establishes due to + * simultaneous resets on both sides. + * + * To avoid this, the function implements randomized polling intervals when the + * link is down. It ensures that reset intervals are desynchronized by + * introducing a random delay between a configured minimum and maximum range. + * When the link is up, a fixed polling interval is used to minimize overhead. + * + * This mechanism guarantees that the link will reestablish within 10 seconds + * in the worst-case scenario. + * + * Return: Time (in jiffies) until the next update event for the PHY state + * machine. + */ +static unsigned int dp83tg720_get_next_update_time(struct phy_device *phydev) +{ + unsigned int next_time_jiffies; + + if (phydev->link) { + /* When the link is up, use a fixed 1000ms interval + * (in jiffies) + */ + next_time_jiffies = + msecs_to_jiffies(DP83TG720S_POLL_ACTIVE_LINK); + } else { + unsigned int min_jiffies, max_jiffies, rand_jiffies; + + /* When the link is down, randomize interval between min/max + * (in jiffies) + */ + min_jiffies = msecs_to_jiffies(DP83TG720S_POLL_NO_LINK_MIN); + max_jiffies = msecs_to_jiffies(DP83TG720S_POLL_NO_LINK_MAX); + + rand_jiffies = min_jiffies + + get_random_u32_below(max_jiffies - min_jiffies + 1); + next_time_jiffies = rand_jiffies; + } + + /* Ensure the polling time is at least one jiffy */ + return max(next_time_jiffies, 1U); +} + static struct phy_driver dp83tg720_driver[] = { { PHY_ID_MATCH_MODEL(DP83TG720S_PHY_ID), .name = "TI DP83TG720S", + .flags = PHY_POLL_CABLE_TEST, + .probe = dp83tg720_probe, .config_aneg = dp83tg720_config_aneg, .read_status = dp83tg720_read_status, .get_features = genphy_c45_pma_read_ext_abilities, .config_init = dp83tg720_config_init, .get_sqi = dp83tg720_get_sqi, .get_sqi_max = dp83tg720_get_sqi_max, + .cable_test_start = dp83tg720_cable_test_start, + .cable_test_get_status = dp83tg720_cable_test_get_status, + .get_link_stats = dp83tg720_get_link_stats, + .get_phy_stats = dp83tg720_get_phy_stats, + .update_stats = dp83tg720_update_stats, + .get_next_update_time = dp83tg720_get_next_update_time, .suspend = genphy_suspend, .resume = genphy_resume, } }; module_phy_driver(dp83tg720_driver); -static struct mdio_device_id __maybe_unused dp83tg720_tbl[] = { +static const struct mdio_device_id __maybe_unused dp83tg720_tbl[] = { { PHY_ID_MATCH_MODEL(DP83TG720S_PHY_ID) }, { } }; |