drivers/net/ethernet/intel/e1000e/ptp.c

   1 /* Intel PRO/1000 Linux driver
   2  * Copyright(c) 1999 - 2015 Intel Corporation.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms and conditions of the GNU General Public License,
   6  * version 2, as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  *
  13  * The full GNU General Public License is included in this distribution in
  14  * the file called "COPYING".
  15  *
  16  * Contact Information:
  17  * Linux NICS <linux.nics@intel.com>
  18  * e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
  19  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  20  */
  21
  22 /* PTP 1588 Hardware Clock (PHC)
  23  * Derived from PTP Hardware Clock driver for Intel 82576 and 82580 (igb)
  24  * Copyright (C) 2011 Richard Cochran <richardcochran@gmail.com>
  25  */
  26
  27 #include "e1000.h"
  28
  29 /**
  30  * e1000e_phc_adjfreq - adjust the frequency of the hardware clock
  31  * @ptp: ptp clock structure
  32  * @delta: Desired frequency change in parts per billion
  33  *
  34  * Adjust the frequency of the PHC cycle counter by the indicated delta from
  35  * the base frequency.
  36  **/
  37 static int e1000e_phc_adjfreq(struct ptp_clock_info *ptp, s32 delta)
  38 {
  39         struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
  40                                                      ptp_clock_info);
  41         struct e1000_hw *hw = &adapter->hw;
  42         bool neg_adj = false;
  43         unsigned long flags;
  44         u64 adjustment;
  45         u32 timinca, incvalue;
  46         s32 ret_val;
  47
  48         if ((delta > ptp->max_adj) || (delta <= -1000000000))
  49                 return -EINVAL;
  50
  51         if (delta < 0) {
  52                 neg_adj = true;
  53                 delta = -delta;
  54         }
  55
  56         /* Get the System Time Register SYSTIM base frequency */
  57         ret_val = e1000e_get_base_timinca(adapter, &timinca);
  58         if (ret_val)
  59                 return ret_val;
  60
  61         spin_lock_irqsave(&adapter->systim_lock, flags);
  62
  63         incvalue = timinca & E1000_TIMINCA_INCVALUE_MASK;
  64
  65         adjustment = incvalue;
  66         adjustment *= delta;
  67         adjustment = div_u64(adjustment, 1000000000);
  68
  69         incvalue = neg_adj ? (incvalue - adjustment) : (incvalue + adjustment);
  70
  71         timinca &= ~E1000_TIMINCA_INCVALUE_MASK;
  72         timinca |= incvalue;
  73
  74         ew32(TIMINCA, timinca);
  75
  76         spin_unlock_irqrestore(&adapter->systim_lock, flags);
  77
  78         return 0;
  79 }
  80
  81 /**
  82  * e1000e_phc_adjtime - Shift the time of the hardware clock
  83  * @ptp: ptp clock structure
  84  * @delta: Desired change in nanoseconds
  85  *
  86  * Adjust the timer by resetting the timecounter structure.
  87  **/
  88 static int e1000e_phc_adjtime(struct ptp_clock_info *ptp, s64 delta)
  89 {
  90         struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
  91                                                      ptp_clock_info);
  92         unsigned long flags;
  93
  94         spin_lock_irqsave(&adapter->systim_lock, flags);
  95         timecounter_adjtime(&adapter->tc, delta);
  96         spin_unlock_irqrestore(&adapter->systim_lock, flags);
  97
  98         return 0;
  99 }
 100
 101 /**
 102  * e1000e_phc_gettime - Reads the current time from the hardware clock
 103  * @ptp: ptp clock structure
 104  * @ts: timespec structure to hold the current time value
 105  *
 106  * Read the timecounter and return the correct value in ns after converting
 107  * it into a struct timespec.
 108  **/
 109 static int e1000e_phc_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
 110 {
 111         struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
 112                                                      ptp_clock_info);
 113         unsigned long flags;
 114         u64 cycles, ns;
 115
 116         spin_lock_irqsave(&adapter->systim_lock, flags);
 117
 118         /* Use timecounter_cyc2time() to allow non-monotonic SYSTIM readings */
 119         cycles = adapter->cc.read(&adapter->cc);
 120         ns = timecounter_cyc2time(&adapter->tc, cycles);
 121
 122         spin_unlock_irqrestore(&adapter->systim_lock, flags);
 123
 124         *ts = ns_to_timespec64(ns);
 125
 126         return 0;
 127 }
 128
 129 /**
 130  * e1000e_phc_settime - Set the current time on the hardware clock
 131  * @ptp: ptp clock structure
 132  * @ts: timespec containing the new time for the cycle counter
 133  *
 134  * Reset the timecounter to use a new base value instead of the kernel
 135  * wall timer value.
 136  **/
 137 static int e1000e_phc_settime(struct ptp_clock_info *ptp,
 138                               const struct timespec64 *ts)
 139 {
 140         struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
 141                                                      ptp_clock_info);
 142         unsigned long flags;
 143         u64 ns;
 144
 145         ns = timespec64_to_ns(ts);
 146
 147         /* reset the timecounter */
 148         spin_lock_irqsave(&adapter->systim_lock, flags);
 149         timecounter_init(&adapter->tc, &adapter->cc, ns);
 150         spin_unlock_irqrestore(&adapter->systim_lock, flags);
 151
 152         return 0;
 153 }
 154
 155 /**
 156  * e1000e_phc_enable - enable or disable an ancillary feature
 157  * @ptp: ptp clock structure
 158  * @request: Desired resource to enable or disable
 159  * @on: Caller passes one to enable or zero to disable
 160  *
 161  * Enable (or disable) ancillary features of the PHC subsystem.
 162  * Currently, no ancillary features are supported.
 163  **/
 164 static int e1000e_phc_enable(struct ptp_clock_info __always_unused *ptp,
 165                              struct ptp_clock_request __always_unused *request,
 166                              int __always_unused on)
 167 {
 168         return -EOPNOTSUPP;
 169 }
 170
 171 static void e1000e_systim_overflow_work(struct work_struct *work)
 172 {
 173         struct e1000_adapter *adapter = container_of(work, struct e1000_adapter,
 174                                                      systim_overflow_work.work);
 175         struct e1000_hw *hw = &adapter->hw;
 176         struct timespec64 ts;
 177         u64 ns;
 178
 179         /* Update the timecounter */
 180         ns = timecounter_read(&adapter->tc);
 181
 182         ts = ns_to_timespec64(ns);
 183         e_dbg("SYSTIM overflow check at %lld.%09lu\n",
 184               (long long) ts.tv_sec, ts.tv_nsec);
 185
 186         schedule_delayed_work(&adapter->systim_overflow_work,
 187                               E1000_SYSTIM_OVERFLOW_PERIOD);
 188 }
 189
 190 static const struct ptp_clock_info e1000e_ptp_clock_info = {
 191         .owner          = THIS_MODULE,
 192         .n_alarm        = 0,
 193         .n_ext_ts       = 0,
 194         .n_per_out      = 0,
 195         .n_pins         = 0,
 196         .pps            = 0,
 197         .adjfreq        = e1000e_phc_adjfreq,
 198         .adjtime        = e1000e_phc_adjtime,
 199         .gettime64      = e1000e_phc_gettime,
 200         .settime64      = e1000e_phc_settime,
 201         .enable         = e1000e_phc_enable,
 202 };
 203
 204 /**
 205  * e1000e_ptp_init - initialize PTP for devices which support it
 206  * @adapter: board private structure
 207  *
 208  * This function performs the required steps for enabling PTP support.
 209  * If PTP support has already been loaded it simply calls the cyclecounter
 210  * init routine and exits.
 211  **/
 212 void e1000e_ptp_init(struct e1000_adapter *adapter)
 213 {
 214         struct e1000_hw *hw = &adapter->hw;
 215
 216         adapter->ptp_clock = NULL;
 217
 218         if (!(adapter->flags & FLAG_HAS_HW_TIMESTAMP))
 219                 return;
 220
 221         adapter->ptp_clock_info = e1000e_ptp_clock_info;
 222
 223         snprintf(adapter->ptp_clock_info.name,
 224                  sizeof(adapter->ptp_clock_info.name), "%pm",
 225                  adapter->netdev->perm_addr);
 226
 227         switch (hw->mac.type) {
 228         case e1000_pch2lan:
 229         case e1000_pch_lpt:
 230         case e1000_pch_spt:
 231                 if (((hw->mac.type != e1000_pch_lpt) &&
 232                      (hw->mac.type != e1000_pch_spt)) ||
 233                     (er32(TSYNCRXCTL) & E1000_TSYNCRXCTL_SYSCFI)) {
 234                         adapter->ptp_clock_info.max_adj = 24000000 - 1;
 235                         break;
 236                 }
 237                 /* fall-through */
 238         case e1000_82574:
 239         case e1000_82583:
 240                 adapter->ptp_clock_info.max_adj = 600000000 - 1;
 241                 break;
 242         default:
 243                 break;
 244         }
 245
 246         INIT_DELAYED_WORK(&adapter->systim_overflow_work,
 247                           e1000e_systim_overflow_work);
 248
 249         schedule_delayed_work(&adapter->systim_overflow_work,
 250                               E1000_SYSTIM_OVERFLOW_PERIOD);
 251
 252         adapter->ptp_clock = ptp_clock_register(&adapter->ptp_clock_info,
 253                                                 &adapter->pdev->dev);
 254         if (IS_ERR(adapter->ptp_clock)) {
 255                 adapter->ptp_clock = NULL;
 256                 e_err("ptp_clock_register failed\n");
 257         } else {
 258                 e_info("registered PHC clock\n");
 259         }
 260 }
 261
 262 /**
 263  * e1000e_ptp_remove - disable PTP device and stop the overflow check
 264  * @adapter: board private structure
 265  *
 266  * Stop the PTP support, and cancel the delayed work.
 267  **/
 268 void e1000e_ptp_remove(struct e1000_adapter *adapter)
 269 {
 270         if (!(adapter->flags & FLAG_HAS_HW_TIMESTAMP))
 271                 return;
 272
 273         cancel_delayed_work_sync(&adapter->systim_overflow_work);
 274
 275         if (adapter->ptp_clock) {
 276                 ptp_clock_unregister(adapter->ptp_clock);
 277                 adapter->ptp_clock = NULL;
 278                 e_info("removed PHC\n");
 279         }
 280 }