| /* |
| * PTP Hardware Clock (PHC) driver for the Intel 82576 and 82580 |
| * |
| * Copyright (C) 2011 Richard Cochran <richardcochran@gmail.com> |
| * |
| * 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. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License along |
| * with this program; if not, write to the Free Software Foundation, Inc., |
| * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| */ |
| #include <linux/module.h> |
| #include <linux/device.h> |
| #include <linux/pci.h> |
| |
| #include "igb.h" |
| |
| #define INCVALUE_MASK 0x7fffffff |
| #define ISGN 0x80000000 |
| |
| /* |
| * 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 availible. 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. |
| */ |
| |
| #define IGB_OVERFLOW_PERIOD (HZ * 60 * 9) |
| #define INCPERIOD_82576 (1 << E1000_TIMINCA_16NS_SHIFT) |
| #define INCVALUE_82576_MASK ((1 << E1000_TIMINCA_16NS_SHIFT) - 1) |
| #define INCVALUE_82576 (16 << IGB_82576_TSYNC_SHIFT) |
| #define IGB_NBITS_82580 40 |
| |
| /* |
| * SYSTIM read access for the 82576 |
| */ |
| |
| static cycle_t igb_82576_systim_read(const struct cyclecounter *cc) |
| { |
| u64 val; |
| u32 lo, hi; |
| struct igb_adapter *igb = container_of(cc, struct igb_adapter, cc); |
| struct e1000_hw *hw = &igb->hw; |
| |
| lo = rd32(E1000_SYSTIML); |
| hi = rd32(E1000_SYSTIMH); |
| |
| val = ((u64) hi) << 32; |
| val |= lo; |
| |
| return val; |
| } |
| |
| /* |
| * SYSTIM read access for the 82580 |
| */ |
| |
| static cycle_t igb_82580_systim_read(const struct cyclecounter *cc) |
| { |
| u64 val; |
| u32 lo, hi, jk; |
| struct igb_adapter *igb = container_of(cc, struct igb_adapter, cc); |
| struct e1000_hw *hw = &igb->hw; |
| |
| /* |
| * The timestamp latches on lowest register read. For the 82580 |
| * the lowest register is SYSTIMR instead of SYSTIML. However we only |
| * need to provide nanosecond resolution, so we just ignore it. |
| */ |
| jk = rd32(E1000_SYSTIMR); |
| lo = rd32(E1000_SYSTIML); |
| hi = rd32(E1000_SYSTIMH); |
| |
| val = ((u64) hi) << 32; |
| val |= lo; |
| |
| return val; |
| } |
| |
| /* |
| * PTP clock operations |
| */ |
| |
| static int ptp_82576_adjfreq(struct ptp_clock_info *ptp, s32 ppb) |
| { |
| u64 rate; |
| u32 incvalue; |
| int neg_adj = 0; |
| struct igb_adapter *igb = container_of(ptp, struct igb_adapter, caps); |
| struct e1000_hw *hw = &igb->hw; |
| |
| if (ppb < 0) { |
| neg_adj = 1; |
| ppb = -ppb; |
| } |
| rate = ppb; |
| rate <<= 14; |
| rate = div_u64(rate, 1953125); |
| |
| incvalue = 16 << IGB_82576_TSYNC_SHIFT; |
| |
| if (neg_adj) |
| incvalue -= rate; |
| else |
| incvalue += rate; |
| |
| wr32(E1000_TIMINCA, INCPERIOD_82576 | (incvalue & INCVALUE_82576_MASK)); |
| |
| return 0; |
| } |
| |
| static int ptp_82580_adjfreq(struct ptp_clock_info *ptp, s32 ppb) |
| { |
| u64 rate; |
| u32 inca; |
| int neg_adj = 0; |
| struct igb_adapter *igb = container_of(ptp, struct igb_adapter, caps); |
| struct e1000_hw *hw = &igb->hw; |
| |
| if (ppb < 0) { |
| neg_adj = 1; |
| ppb = -ppb; |
| } |
| rate = ppb; |
| rate <<= 26; |
| rate = div_u64(rate, 1953125); |
| |
| inca = rate & INCVALUE_MASK; |
| if (neg_adj) |
| inca |= ISGN; |
| |
| wr32(E1000_TIMINCA, inca); |
| |
| return 0; |
| } |
| |
| static int igb_adjtime(struct ptp_clock_info *ptp, s64 delta) |
| { |
| s64 now; |
| unsigned long flags; |
| struct igb_adapter *igb = container_of(ptp, struct igb_adapter, caps); |
| |
| spin_lock_irqsave(&igb->tmreg_lock, flags); |
| |
| now = timecounter_read(&igb->tc); |
| now += delta; |
| timecounter_init(&igb->tc, &igb->cc, now); |
| |
| spin_unlock_irqrestore(&igb->tmreg_lock, flags); |
| |
| return 0; |
| } |
| |
| static int igb_gettime(struct ptp_clock_info *ptp, struct timespec *ts) |
| { |
| u64 ns; |
| u32 remainder; |
| unsigned long flags; |
| struct igb_adapter *igb = container_of(ptp, struct igb_adapter, caps); |
| |
| spin_lock_irqsave(&igb->tmreg_lock, flags); |
| |
| ns = timecounter_read(&igb->tc); |
| |
| spin_unlock_irqrestore(&igb->tmreg_lock, flags); |
| |
| ts->tv_sec = div_u64_rem(ns, 1000000000, &remainder); |
| ts->tv_nsec = remainder; |
| |
| return 0; |
| } |
| |
| static int igb_settime(struct ptp_clock_info *ptp, const struct timespec *ts) |
| { |
| u64 ns; |
| unsigned long flags; |
| struct igb_adapter *igb = container_of(ptp, struct igb_adapter, caps); |
| |
| ns = ts->tv_sec * 1000000000ULL; |
| ns += ts->tv_nsec; |
| |
| spin_lock_irqsave(&igb->tmreg_lock, flags); |
| |
| timecounter_init(&igb->tc, &igb->cc, ns); |
| |
| spin_unlock_irqrestore(&igb->tmreg_lock, flags); |
| |
| return 0; |
| } |
| |
| static int ptp_82576_enable(struct ptp_clock_info *ptp, |
| struct ptp_clock_request *rq, int on) |
| { |
| return -EOPNOTSUPP; |
| } |
| |
| static int ptp_82580_enable(struct ptp_clock_info *ptp, |
| struct ptp_clock_request *rq, int on) |
| { |
| return -EOPNOTSUPP; |
| } |
| |
| static void igb_overflow_check(struct work_struct *work) |
| { |
| struct timespec ts; |
| struct igb_adapter *igb = |
| container_of(work, struct igb_adapter, overflow_work.work); |
| |
| igb_gettime(&igb->caps, &ts); |
| |
| pr_debug("igb overflow check at %ld.%09lu\n", ts.tv_sec, ts.tv_nsec); |
| |
| schedule_delayed_work(&igb->overflow_work, IGB_OVERFLOW_PERIOD); |
| } |
| |
| void igb_ptp_init(struct igb_adapter *adapter) |
| { |
| struct e1000_hw *hw = &adapter->hw; |
| |
| switch (hw->mac.type) { |
| case e1000_i210: |
| case e1000_i211: |
| case e1000_i350: |
| case e1000_82580: |
| adapter->caps.owner = THIS_MODULE; |
| strcpy(adapter->caps.name, "igb-82580"); |
| adapter->caps.max_adj = 62499999; |
| adapter->caps.n_ext_ts = 0; |
| adapter->caps.pps = 0; |
| adapter->caps.adjfreq = ptp_82580_adjfreq; |
| adapter->caps.adjtime = igb_adjtime; |
| adapter->caps.gettime = igb_gettime; |
| adapter->caps.settime = igb_settime; |
| adapter->caps.enable = ptp_82580_enable; |
| adapter->cc.read = igb_82580_systim_read; |
| adapter->cc.mask = CLOCKSOURCE_MASK(IGB_NBITS_82580); |
| adapter->cc.mult = 1; |
| adapter->cc.shift = 0; |
| /* Enable the timer functions by clearing bit 31. */ |
| wr32(E1000_TSAUXC, 0x0); |
| break; |
| |
| case e1000_82576: |
| adapter->caps.owner = THIS_MODULE; |
| strcpy(adapter->caps.name, "igb-82576"); |
| adapter->caps.max_adj = 1000000000; |
| adapter->caps.n_ext_ts = 0; |
| adapter->caps.pps = 0; |
| adapter->caps.adjfreq = ptp_82576_adjfreq; |
| adapter->caps.adjtime = igb_adjtime; |
| adapter->caps.gettime = igb_gettime; |
| adapter->caps.settime = igb_settime; |
| adapter->caps.enable = ptp_82576_enable; |
| adapter->cc.read = igb_82576_systim_read; |
| adapter->cc.mask = CLOCKSOURCE_MASK(64); |
| adapter->cc.mult = 1; |
| adapter->cc.shift = IGB_82576_TSYNC_SHIFT; |
| /* Dial the nominal frequency. */ |
| wr32(E1000_TIMINCA, INCPERIOD_82576 | INCVALUE_82576); |
| break; |
| |
| default: |
| adapter->ptp_clock = NULL; |
| return; |
| } |
| |
| wrfl(); |
| |
| timecounter_init(&adapter->tc, &adapter->cc, |
| ktime_to_ns(ktime_get_real())); |
| |
| INIT_DELAYED_WORK(&adapter->overflow_work, igb_overflow_check); |
| |
| spin_lock_init(&adapter->tmreg_lock); |
| |
| schedule_delayed_work(&adapter->overflow_work, IGB_OVERFLOW_PERIOD); |
| |
| adapter->ptp_clock = ptp_clock_register(&adapter->caps); |
| if (IS_ERR(adapter->ptp_clock)) { |
| adapter->ptp_clock = NULL; |
| dev_err(&adapter->pdev->dev, "ptp_clock_register failed\n"); |
| } else |
| dev_info(&adapter->pdev->dev, "added PHC on %s\n", |
| adapter->netdev->name); |
| } |
| |
| void igb_ptp_remove(struct igb_adapter *adapter) |
| { |
| switch (adapter->hw.mac.type) { |
| case e1000_i211: |
| case e1000_i210: |
| case e1000_i350: |
| case e1000_82580: |
| case e1000_82576: |
| cancel_delayed_work_sync(&adapter->overflow_work); |
| break; |
| default: |
| return; |
| } |
| |
| if (adapter->ptp_clock) { |
| ptp_clock_unregister(adapter->ptp_clock); |
| dev_info(&adapter->pdev->dev, "removed PHC on %s\n", |
| adapter->netdev->name); |
| } |
| } |
| |
| /** |
| * igb_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. |
| **/ |
| void igb_systim_to_hwtstamp(struct igb_adapter *adapter, |
| struct skb_shared_hwtstamps *hwtstamps, |
| u64 systim) |
| { |
| u64 ns; |
| unsigned long flags; |
| |
| switch (adapter->hw.mac.type) { |
| case e1000_i210: |
| case e1000_i211: |
| case e1000_i350: |
| case e1000_82580: |
| case e1000_82576: |
| break; |
| default: |
| return; |
| } |
| |
| spin_lock_irqsave(&adapter->tmreg_lock, flags); |
| |
| ns = timecounter_cyc2time(&adapter->tc, systim); |
| |
| spin_unlock_irqrestore(&adapter->tmreg_lock, flags); |
| |
| memset(hwtstamps, 0, sizeof(*hwtstamps)); |
| hwtstamps->hwtstamp = ns_to_ktime(ns); |
| } |