// SPDX-License-Identifier: GPL-2.0+ /* Copyright (C) 2011 Richard Cochran <[email protected]> */ #include <linux/module.h> #include <linux/device.h> #include <linux/pci.h> #include <linux/ptp_classify.h> #include "igb.h" #define INCVALUE_MASK … #define ISGN … /* The 82580 timesync updates the system timer every 8ns by 8ns, * and this update value cannot be reprogrammed. * * Neither the 82576 nor the 82580 offer registers wide enough to hold * nanoseconds time values for very long. For the 82580, SYSTIM always * counts nanoseconds, but the upper 24 bits are not available. The * frequency is adjusted by changing the 32 bit fractional nanoseconds * register, TIMINCA. * * For the 82576, the SYSTIM register time unit is affect by the * choice of the 24 bit TININCA:IV (incvalue) field. Five bits of this * field are needed to provide the nominal 16 nanosecond period, * leaving 19 bits for fractional nanoseconds. * * We scale the NIC clock cycle by a large factor so that relatively * small clock corrections can be added or subtracted at each clock * tick. The drawbacks of a large factor are a) that the clock * register overflows more quickly (not such a big deal) and b) that * the increment per tick has to fit into 24 bits. As a result we * need to use a shift of 19 so we can fit a value of 16 into the * TIMINCA register. * * * SYSTIMH SYSTIML * +--------------+ +---+---+------+ * 82576 | 32 | | 8 | 5 | 19 | * +--------------+ +---+---+------+ * \________ 45 bits _______/ fract * * +----------+---+ +--------------+ * 82580 | 24 | 8 | | 32 | * +----------+---+ +--------------+ * reserved \______ 40 bits _____/ * * * The 45 bit 82576 SYSTIM overflows every * 2^45 * 10^-9 / 3600 = 9.77 hours. * * The 40 bit 82580 SYSTIM overflows every * 2^40 * 10^-9 / 60 = 18.3 minutes. * * SYSTIM is converted to real time using a timecounter. As * timecounter_cyc2time() allows old timestamps, the timecounter needs * to be updated at least once per half of the SYSTIM interval. * Scheduling of delayed work is not very accurate, and also the NIC * clock can be adjusted to run up to 6% faster and the system clock * up to 10% slower, so we aim for 6 minutes to be sure the actual * interval in the NIC time is shorter than 9.16 minutes. */ #define IGB_SYSTIM_OVERFLOW_PERIOD … #define IGB_PTP_TX_TIMEOUT … #define INCPERIOD_82576 … #define INCVALUE_82576_MASK … #define INCVALUE_82576 … #define IGB_NBITS_82580 … #define IGB_82580_BASE_PERIOD … static void igb_ptp_tx_hwtstamp(struct igb_adapter *adapter); static void igb_ptp_sdp_init(struct igb_adapter *adapter); /* SYSTIM read access for the 82576 */ static u64 igb_ptp_read_82576(const struct cyclecounter *cc) { … } /* SYSTIM read access for the 82580 */ static u64 igb_ptp_read_82580(const struct cyclecounter *cc) { … } /* SYSTIM read access for I210/I211 */ static void igb_ptp_read_i210(struct igb_adapter *adapter, struct timespec64 *ts) { … } static void igb_ptp_write_i210(struct igb_adapter *adapter, const struct timespec64 *ts) { … } /** * igb_ptp_systim_to_hwtstamp - convert system time value to hw timestamp * @adapter: board private structure * @hwtstamps: timestamp structure to update * @systim: unsigned 64bit system time value. * * We need to convert the system time value stored in the RX/TXSTMP registers * into a hwtstamp which can be used by the upper level timestamping functions. * * The 'tmreg_lock' spinlock is used to protect the consistency of the * system time value. This is needed because reading the 64 bit time * value involves reading two (or three) 32 bit registers. The first * read latches the value. Ditto for writing. * * In addition, here have extended the system time with an overflow * counter in software. **/ static void igb_ptp_systim_to_hwtstamp(struct igb_adapter *adapter, struct skb_shared_hwtstamps *hwtstamps, u64 systim) { … } /* PTP clock operations */ static int igb_ptp_adjfine_82576(struct ptp_clock_info *ptp, long scaled_ppm) { … } static int igb_ptp_adjfine_82580(struct ptp_clock_info *ptp, long scaled_ppm) { … } static int igb_ptp_adjtime_82576(struct ptp_clock_info *ptp, s64 delta) { … } static int igb_ptp_adjtime_i210(struct ptp_clock_info *ptp, s64 delta) { … } static int igb_ptp_gettimex_82576(struct ptp_clock_info *ptp, struct timespec64 *ts, struct ptp_system_timestamp *sts) { … } static int igb_ptp_gettimex_82580(struct ptp_clock_info *ptp, struct timespec64 *ts, struct ptp_system_timestamp *sts) { … } static int igb_ptp_gettimex_i210(struct ptp_clock_info *ptp, struct timespec64 *ts, struct ptp_system_timestamp *sts) { … } static int igb_ptp_settime_82576(struct ptp_clock_info *ptp, const struct timespec64 *ts) { … } static int igb_ptp_settime_i210(struct ptp_clock_info *ptp, const struct timespec64 *ts) { … } static void igb_pin_direction(int pin, int input, u32 *ctrl, u32 *ctrl_ext) { … } static void igb_pin_extts(struct igb_adapter *igb, int chan, int pin) { … } static void igb_pin_perout(struct igb_adapter *igb, int chan, int pin, int freq) { … } static int igb_ptp_feature_enable_82580(struct ptp_clock_info *ptp, struct ptp_clock_request *rq, int on) { … } static int igb_ptp_feature_enable_i210(struct ptp_clock_info *ptp, struct ptp_clock_request *rq, int on) { … } static int igb_ptp_feature_enable(struct ptp_clock_info *ptp, struct ptp_clock_request *rq, int on) { … } static int igb_ptp_verify_pin(struct ptp_clock_info *ptp, unsigned int pin, enum ptp_pin_function func, unsigned int chan) { … } /** * igb_ptp_tx_work * @work: pointer to work struct * * This work function polls the TSYNCTXCTL valid bit to determine when a * timestamp has been taken for the current stored skb. **/ static void igb_ptp_tx_work(struct work_struct *work) { … } static void igb_ptp_overflow_check(struct work_struct *work) { … } /** * igb_ptp_rx_hang - detect error case when Rx timestamp registers latched * @adapter: private network adapter structure * * This watchdog task is scheduled to detect error case where hardware has * dropped an Rx packet that was timestamped when the ring is full. The * particular error is rare but leaves the device in a state unable to timestamp * any future packets. **/ void igb_ptp_rx_hang(struct igb_adapter *adapter) { … } /** * igb_ptp_tx_hang - detect error case where Tx timestamp never finishes * @adapter: private network adapter structure */ void igb_ptp_tx_hang(struct igb_adapter *adapter) { … } /** * igb_ptp_tx_hwtstamp - utility function which checks for TX time stamp * @adapter: Board private structure. * * If we were asked to do hardware stamping and such a time stamp is * available, then it must have been for this skb here because we only * allow only one such packet into the queue. **/ static void igb_ptp_tx_hwtstamp(struct igb_adapter *adapter) { … } /** * igb_ptp_rx_pktstamp - retrieve Rx per packet timestamp * @q_vector: Pointer to interrupt specific structure * @va: Pointer to address containing Rx buffer * @timestamp: Pointer where timestamp will be stored * * This function is meant to retrieve a timestamp from the first buffer of an * incoming frame. The value is stored in little endian format starting on * byte 8 * * Returns: The timestamp header length or 0 if not available **/ int igb_ptp_rx_pktstamp(struct igb_q_vector *q_vector, void *va, ktime_t *timestamp) { … } /** * igb_ptp_rx_rgtstamp - retrieve Rx timestamp stored in register * @q_vector: Pointer to interrupt specific structure * @skb: Buffer containing timestamp and packet * * This function is meant to retrieve a timestamp from the internal registers * of the adapter and store it in the skb. **/ void igb_ptp_rx_rgtstamp(struct igb_q_vector *q_vector, struct sk_buff *skb) { … } /** * igb_ptp_get_ts_config - get hardware time stamping config * @netdev: netdev struct * @ifr: interface struct * * Get the hwtstamp_config settings to return to the user. Rather than attempt * to deconstruct the settings from the registers, just return a shadow copy * of the last known settings. **/ int igb_ptp_get_ts_config(struct net_device *netdev, struct ifreq *ifr) { … } /** * igb_ptp_set_timestamp_mode - setup hardware for timestamping * @adapter: networking device structure * @config: hwtstamp configuration * * Outgoing time stamping can be enabled and disabled. Play nice and * disable it when requested, although it shouldn't case any overhead * when no packet needs it. At most one packet in the queue may be * marked for time stamping, otherwise it would be impossible to tell * for sure to which packet the hardware time stamp belongs. * * Incoming time stamping has to be configured via the hardware * filters. Not all combinations are supported, in particular event * type has to be specified. Matching the kind of event packet is * not supported, with the exception of "all V2 events regardless of * level 2 or 4". */ static int igb_ptp_set_timestamp_mode(struct igb_adapter *adapter, struct hwtstamp_config *config) { … } /** * igb_ptp_set_ts_config - set hardware time stamping config * @netdev: netdev struct * @ifr: interface struct * **/ int igb_ptp_set_ts_config(struct net_device *netdev, struct ifreq *ifr) { … } /** * igb_ptp_init - Initialize PTP functionality * @adapter: Board private structure * * This function is called at device probe to initialize the PTP * functionality. */ void igb_ptp_init(struct igb_adapter *adapter) { … } /** * igb_ptp_sdp_init - utility function which inits the SDP config structs * @adapter: Board private structure. **/ void igb_ptp_sdp_init(struct igb_adapter *adapter) { … } /** * igb_ptp_suspend - Disable PTP work items and prepare for suspend * @adapter: Board private structure * * This function stops the overflow check work and PTP Tx timestamp work, and * will prepare the device for OS suspend. */ void igb_ptp_suspend(struct igb_adapter *adapter) { … } /** * igb_ptp_stop - Disable PTP device and stop the overflow check. * @adapter: Board private structure. * * This function stops the PTP support and cancels the delayed work. **/ void igb_ptp_stop(struct igb_adapter *adapter) { … } /** * igb_ptp_reset - Re-enable the adapter for PTP following a reset. * @adapter: Board private structure. * * This function handles the reset work required to re-enable the PTP device. **/ void igb_ptp_reset(struct igb_adapter *adapter) { … }