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

   1 /* Intel PRO/1000 Linux driver
   2  * Copyright(c) 1999 - 2014 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         s64 now;
  94
  95         spin_lock_irqsave(&adapter->systim_lock, flags);
  96         now = timecounter_read(&adapter->tc);
  97         now += delta;
  98         timecounter_init(&adapter->tc, &adapter->cc, now);
  99         spin_unlock_irqrestore(&adapter->systim_lock, flags);
 100
 101         return 0;
 102 }
 103
 104 /**
 105  * e1000e_phc_gettime - Reads the current time from the hardware clock
 106  * @ptp: ptp clock structure
 107  * @ts: timespec structure to hold the current time value
 108  *
 109  * Read the timecounter and return the correct value in ns after converting
 110  * it into a struct timespec.
 111  **/
 112 static int e1000e_phc_gettime(struct ptp_clock_info *ptp, struct timespec *ts)
 113 {
 114         struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
 115                                                      ptp_clock_info);
 116         unsigned long flags;
 117         u32 remainder;
 118         u64 ns;
 119
 120         spin_lock_irqsave(&adapter->systim_lock, flags);
 121         ns = timecounter_read(&adapter->tc);
 122         spin_unlock_irqrestore(&adapter->systim_lock, flags);
 123
 124         ts->tv_sec = div_u64_rem(ns, NSEC_PER_SEC, &remainder);
 125         ts->tv_nsec = remainder;
 126
 127         return 0;
 128 }
 129
 130 /**
 131  * e1000e_phc_settime - Set the current time on the hardware clock
 132  * @ptp: ptp clock structure
 133  * @ts: timespec containing the new time for the cycle counter
 134  *
 135  * Reset the timecounter to use a new base value instead of the kernel
 136  * wall timer value.
 137  **/
 138 static int e1000e_phc_settime(struct ptp_clock_info *ptp,
 139                               const struct timespec *ts)
 140 {
 141         struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
 142                                                      ptp_clock_info);
 143         unsigned long flags;
 144         u64 ns;
 145
 146         ns = timespec_to_ns(ts);
 147
 148         /* reset the timecounter */
 149         spin_lock_irqsave(&adapter->systim_lock, flags);
 150         timecounter_init(&adapter->tc, &adapter->cc, ns);
 151         spin_unlock_irqrestore(&adapter->systim_lock, flags);
 152
 153         return 0;
 154 }
 155
 156 /**
 157  * e1000e_phc_enable - enable or disable an ancillary feature
 158  * @ptp: ptp clock structure
 159  * @request: Desired resource to enable or disable
 160  * @on: Caller passes one to enable or zero to disable
 161  *
 162  * Enable (or disable) ancillary features of the PHC subsystem.
 163  * Currently, no ancillary features are supported.
 164  **/
 165 static int e1000e_phc_enable(struct ptp_clock_info __always_unused *ptp,
 166                              struct ptp_clock_request __always_unused *request,
 167                              int __always_unused on)
 168 {
 169         return -EOPNOTSUPP;
 170 }
 171
 172 static void e1000e_systim_overflow_work(struct work_struct *work)
 173 {
 174         struct e1000_adapter *adapter = container_of(work, struct e1000_adapter,
 175                                                      systim_overflow_work.work);
 176         struct e1000_hw *hw = &adapter->hw;
 177         struct timespec ts;
 178
 179         adapter->ptp_clock_info.gettime(&adapter->ptp_clock_info, &ts);
 180
 181         e_dbg("SYSTIM overflow check at %ld.%09lu\n", ts.tv_sec, ts.tv_nsec);
 182
 183         schedule_delayed_work(&adapter->systim_overflow_work,
 184                               E1000_SYSTIM_OVERFLOW_PERIOD);
 185 }
 186
 187 static const struct ptp_clock_info e1000e_ptp_clock_info = {
 188         .owner          = THIS_MODULE,
 189         .n_alarm        = 0,
 190         .n_ext_ts       = 0,
 191         .n_per_out      = 0,
 192         .n_pins         = 0,
 193         .pps            = 0,
 194         .adjfreq        = e1000e_phc_adjfreq,
 195         .adjtime        = e1000e_phc_adjtime,
 196         .gettime        = e1000e_phc_gettime,
 197         .settime        = e1000e_phc_settime,
 198         .enable         = e1000e_phc_enable,
 199 };
 200
 201 /**
 202  * e1000e_ptp_init - initialize PTP for devices which support it
 203  * @adapter: board private structure
 204  *
 205  * This function performs the required steps for enabling PTP support.
 206  * If PTP support has already been loaded it simply calls the cyclecounter
 207  * init routine and exits.
 208  **/
 209 void e1000e_ptp_init(struct e1000_adapter *adapter)
 210 {
 211         struct e1000_hw *hw = &adapter->hw;
 212
 213         adapter->ptp_clock = NULL;
 214
 215         if (!(adapter->flags & FLAG_HAS_HW_TIMESTAMP))
 216                 return;
 217
 218         adapter->ptp_clock_info = e1000e_ptp_clock_info;
 219
 220         snprintf(adapter->ptp_clock_info.name,
 221                  sizeof(adapter->ptp_clock_info.name), "%pm",
 222                  adapter->netdev->perm_addr);
 223
 224         switch (hw->mac.type) {
 225         case e1000_pch2lan:
 226         case e1000_pch_lpt:
 227                 if ((hw->mac.type != e1000_pch_lpt) ||
 228                     (er32(TSYNCRXCTL) & E1000_TSYNCRXCTL_SYSCFI)) {
 229                         adapter->ptp_clock_info.max_adj = 24000000 - 1;
 230                         break;
 231                 }
 232                 /* fall-through */
 233         case e1000_82574:
 234         case e1000_82583:
 235                 adapter->ptp_clock_info.max_adj = 600000000 - 1;
 236                 break;
 237         default:
 238                 break;
 239         }
 240
 241         INIT_DELAYED_WORK(&adapter->systim_overflow_work,
 242                           e1000e_systim_overflow_work);
 243
 244         schedule_delayed_work(&adapter->systim_overflow_work,
 245                               E1000_SYSTIM_OVERFLOW_PERIOD);
 246
 247         adapter->ptp_clock = ptp_clock_register(&adapter->ptp_clock_info,
 248                                                 &adapter->pdev->dev);
 249         if (IS_ERR(adapter->ptp_clock)) {
 250                 adapter->ptp_clock = NULL;
 251                 e_err("ptp_clock_register failed\n");
 252         } else {
 253                 e_info("registered PHC clock\n");
 254         }
 255 }
 256
 257 /**
 258  * e1000e_ptp_remove - disable PTP device and stop the overflow check
 259  * @adapter: board private structure
 260  *
 261  * Stop the PTP support, and cancel the delayed work.
 262  **/
 263 void e1000e_ptp_remove(struct e1000_adapter *adapter)
 264 {
 265         if (!(adapter->flags & FLAG_HAS_HW_TIMESTAMP))
 266                 return;
 267
 268         cancel_delayed_work_sync(&adapter->systim_overflow_work);
 269
 270         if (adapter->ptp_clock) {
 271                 ptp_clock_unregister(adapter->ptp_clock);
 272                 adapter->ptp_clock = NULL;
 273                 e_info("removed PHC\n");
 274         }
 275 }