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 #ifdef CONFIG_E1000E_HWTS
  30 #include <linux/clocksource.h>
  31 #include <linux/ktime.h>
  32 #include <asm/tsc.h>
  33 #endif
  34
  35 /**
  36  * e1000e_phc_adjfreq - adjust the frequency of the hardware clock
  37  * @ptp: ptp clock structure
  38  * @delta: Desired frequency change in parts per billion
  39  *
  40  * Adjust the frequency of the PHC cycle counter by the indicated delta from
  41  * the base frequency.
  42  **/
  43 static int e1000e_phc_adjfreq(struct ptp_clock_info *ptp, s32 delta)
  44 {
  45         struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
  46                                                      ptp_clock_info);
  47         struct e1000_hw *hw = &adapter->hw;
  48         bool neg_adj = false;
  49         unsigned long flags;
  50         u64 adjustment;
  51         u32 timinca, incvalue;
  52         s32 ret_val;
  53
  54         if ((delta > ptp->max_adj) || (delta <= -1000000000))
  55                 return -EINVAL;
  56
  57         if (delta < 0) {
  58                 neg_adj = true;
  59                 delta = -delta;
  60         }
  61
  62         /* Get the System Time Register SYSTIM base frequency */
  63         ret_val = e1000e_get_base_timinca(adapter, &timinca);
  64         if (ret_val)
  65                 return ret_val;
  66
  67         spin_lock_irqsave(&adapter->systim_lock, flags);
  68
  69         incvalue = timinca & E1000_TIMINCA_INCVALUE_MASK;
  70
  71         adjustment = incvalue;
  72         adjustment *= delta;
  73         adjustment = div_u64(adjustment, 1000000000);
  74
  75         incvalue = neg_adj ? (incvalue - adjustment) : (incvalue + adjustment);
  76
  77         timinca &= ~E1000_TIMINCA_INCVALUE_MASK;
  78         timinca |= incvalue;
  79
  80         ew32(TIMINCA, timinca);
  81
  82         adapter->ptp_delta = delta;
  83
  84         spin_unlock_irqrestore(&adapter->systim_lock, flags);
  85
  86         return 0;
  87 }
  88
  89 /**
  90  * e1000e_phc_adjtime - Shift the time of the hardware clock
  91  * @ptp: ptp clock structure
  92  * @delta: Desired change in nanoseconds
  93  *
  94  * Adjust the timer by resetting the timecounter structure.
  95  **/
  96 static int e1000e_phc_adjtime(struct ptp_clock_info *ptp, s64 delta)
  97 {
  98         struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
  99                                                      ptp_clock_info);
 100         unsigned long flags;
 101
 102         spin_lock_irqsave(&adapter->systim_lock, flags);
 103         timecounter_adjtime(&adapter->tc, delta);
 104         spin_unlock_irqrestore(&adapter->systim_lock, flags);
 105
 106         return 0;
 107 }
 108
 109 #ifdef CONFIG_E1000E_HWTS
 110 #define MAX_HW_WAIT_COUNT (3)
 111
 112 /**
 113  * e1000e_phc_get_syncdevicetime - Callback given to timekeeping code reads system/device registers
 114  * @device: current device time
 115  * @system: system counter value read synchronously with device time
 116  * @ctx: context provided by timekeeping code
 117  *
 118  * Read device and system (ART) clock simultaneously and return the corrected
 119  * clock values in ns.
 120  **/
 121 static int e1000e_phc_get_syncdevicetime(ktime_t *device,
 122                                          struct system_counterval_t *system,
 123                                          void *ctx)
 124 {
 125         struct e1000_adapter *adapter = (struct e1000_adapter *)ctx;
 126         struct e1000_hw *hw = &adapter->hw;
 127         unsigned long flags;
 128         int i;
 129         u32 tsync_ctrl;
 130         u64 dev_cycles;
 131         u64 sys_cycles;
 132
 133         tsync_ctrl = er32(TSYNCTXCTL);
 134         tsync_ctrl |= E1000_TSYNCTXCTL_START_SYNC |
 135                 E1000_TSYNCTXCTL_MAX_ALLOWED_DLY_MASK;
 136         ew32(TSYNCTXCTL, tsync_ctrl);
 137         for (i = 0; i < MAX_HW_WAIT_COUNT; ++i) {
 138                 udelay(1);
 139                 tsync_ctrl = er32(TSYNCTXCTL);
 140                 if (tsync_ctrl & E1000_TSYNCTXCTL_SYNC_COMP)
 141                         break;
 142         }
 143
 144         if (i == MAX_HW_WAIT_COUNT)
 145                 return -ETIMEDOUT;
 146
 147         dev_cycles = er32(SYSSTMPH);
 148         dev_cycles <<= 32;
 149         dev_cycles |= er32(SYSSTMPL);
 150         spin_lock_irqsave(&adapter->systim_lock, flags);
 151         *device = ns_to_ktime(timecounter_cyc2time(&adapter->tc, dev_cycles));
 152         spin_unlock_irqrestore(&adapter->systim_lock, flags);
 153
 154         sys_cycles = er32(PLTSTMPH);
 155         sys_cycles <<= 32;
 156         sys_cycles |= er32(PLTSTMPL);
 157         *system = convert_art_to_tsc(sys_cycles);
 158
 159         return 0;
 160 }
 161
 162 /**
 163  * e1000e_phc_getsynctime - Reads the current system/device cross timestamp
 164  * @ptp: ptp clock structure
 165  * @cts: structure containing timestamp
 166  *
 167  * Read device and system (ART) clock simultaneously and return the scaled
 168  * clock values in ns.
 169  **/
 170 static int e1000e_phc_getcrosststamp(struct ptp_clock_info *ptp,
 171                                      struct system_device_crosststamp *xtstamp)
 172 {
 173         struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
 174                                                      ptp_clock_info);
 175
 176         return get_device_system_crosststamp(e1000e_phc_get_syncdevicetime,
 177                                                 adapter, NULL, xtstamp);
 178 }
 179 #endif/*CONFIG_E1000E_HWTS*/
 180
 181 /**
 182  * e1000e_phc_gettime - Reads the current time from the hardware clock
 183  * @ptp: ptp clock structure
 184  * @ts: timespec structure to hold the current time value
 185  *
 186  * Read the timecounter and return the correct value in ns after converting
 187  * it into a struct timespec.
 188  **/
 189 static int e1000e_phc_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
 190 {
 191         struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
 192                                                      ptp_clock_info);
 193         unsigned long flags;
 194         u64 cycles, ns;
 195
 196         spin_lock_irqsave(&adapter->systim_lock, flags);
 197
 198         /* Use timecounter_cyc2time() to allow non-monotonic SYSTIM readings */
 199         cycles = adapter->cc.read(&adapter->cc);
 200         ns = timecounter_cyc2time(&adapter->tc, cycles);
 201
 202         spin_unlock_irqrestore(&adapter->systim_lock, flags);
 203
 204         *ts = ns_to_timespec64(ns);
 205
 206         return 0;
 207 }
 208
 209 /**
 210  * e1000e_phc_settime - Set the current time on the hardware clock
 211  * @ptp: ptp clock structure
 212  * @ts: timespec containing the new time for the cycle counter
 213  *
 214  * Reset the timecounter to use a new base value instead of the kernel
 215  * wall timer value.
 216  **/
 217 static int e1000e_phc_settime(struct ptp_clock_info *ptp,
 218                               const struct timespec64 *ts)
 219 {
 220         struct e1000_adapter *adapter = container_of(ptp, struct e1000_adapter,
 221                                                      ptp_clock_info);
 222         unsigned long flags;
 223         u64 ns;
 224
 225         ns = timespec64_to_ns(ts);
 226
 227         /* reset the timecounter */
 228         spin_lock_irqsave(&adapter->systim_lock, flags);
 229         timecounter_init(&adapter->tc, &adapter->cc, ns);
 230         spin_unlock_irqrestore(&adapter->systim_lock, flags);
 231
 232         return 0;
 233 }
 234
 235 /**
 236  * e1000e_phc_enable - enable or disable an ancillary feature
 237  * @ptp: ptp clock structure
 238  * @request: Desired resource to enable or disable
 239  * @on: Caller passes one to enable or zero to disable
 240  *
 241  * Enable (or disable) ancillary features of the PHC subsystem.
 242  * Currently, no ancillary features are supported.
 243  **/
 244 static int e1000e_phc_enable(struct ptp_clock_info __always_unused *ptp,
 245                              struct ptp_clock_request __always_unused *request,
 246                              int __always_unused on)
 247 {
 248         return -EOPNOTSUPP;
 249 }
 250
 251 static void e1000e_systim_overflow_work(struct work_struct *work)
 252 {
 253         struct e1000_adapter *adapter = container_of(work, struct e1000_adapter,
 254                                                      systim_overflow_work.work);
 255         struct e1000_hw *hw = &adapter->hw;
 256         struct timespec64 ts;
 257         u64 ns;
 258
 259         /* Update the timecounter */
 260         ns = timecounter_read(&adapter->tc);
 261
 262         ts = ns_to_timespec64(ns);
 263         e_dbg("SYSTIM overflow check at %lld.%09lu\n",
 264               (long long) ts.tv_sec, ts.tv_nsec);
 265
 266         schedule_delayed_work(&adapter->systim_overflow_work,
 267                               E1000_SYSTIM_OVERFLOW_PERIOD);
 268 }
 269
 270 static const struct ptp_clock_info e1000e_ptp_clock_info = {
 271         .owner          = THIS_MODULE,
 272         .n_alarm        = 0,
 273         .n_ext_ts       = 0,
 274         .n_per_out      = 0,
 275         .n_pins         = 0,
 276         .pps            = 0,
 277         .adjfreq        = e1000e_phc_adjfreq,
 278         .adjtime        = e1000e_phc_adjtime,
 279         .gettime64      = e1000e_phc_gettime,
 280         .settime64      = e1000e_phc_settime,
 281         .enable         = e1000e_phc_enable,
 282 };
 283
 284 /**
 285  * e1000e_ptp_init - initialize PTP for devices which support it
 286  * @adapter: board private structure
 287  *
 288  * This function performs the required steps for enabling PTP support.
 289  * If PTP support has already been loaded it simply calls the cyclecounter
 290  * init routine and exits.
 291  **/
 292 void e1000e_ptp_init(struct e1000_adapter *adapter)
 293 {
 294         struct e1000_hw *hw = &adapter->hw;
 295
 296         adapter->ptp_clock = NULL;
 297
 298         if (!(adapter->flags & FLAG_HAS_HW_TIMESTAMP))
 299                 return;
 300
 301         adapter->ptp_clock_info = e1000e_ptp_clock_info;
 302
 303         snprintf(adapter->ptp_clock_info.name,
 304                  sizeof(adapter->ptp_clock_info.name), "%pm",
 305                  adapter->netdev->perm_addr);
 306
 307         switch (hw->mac.type) {
 308         case e1000_pch2lan:
 309         case e1000_pch_lpt:
 310         case e1000_pch_spt:
 311         case e1000_pch_cnp:
 312                 if ((hw->mac.type < e1000_pch_lpt) ||
 313                     (er32(TSYNCRXCTL) & E1000_TSYNCRXCTL_SYSCFI)) {
 314                         adapter->ptp_clock_info.max_adj = 24000000 - 1;
 315                         break;
 316                 }
 317                 /* fall-through */
 318         case e1000_82574:
 319         case e1000_82583:
 320                 adapter->ptp_clock_info.max_adj = 600000000 - 1;
 321                 break;
 322         default:
 323                 break;
 324         }
 325
 326 #ifdef CONFIG_E1000E_HWTS
 327         /* CPU must have ART and GBe must be from Sunrise Point or greater */
 328         if (hw->mac.type >= e1000_pch_spt && boot_cpu_has(X86_FEATURE_ART))
 329                 adapter->ptp_clock_info.getcrosststamp =
 330                         e1000e_phc_getcrosststamp;
 331 #endif/*CONFIG_E1000E_HWTS*/
 332
 333         INIT_DELAYED_WORK(&adapter->systim_overflow_work,
 334                           e1000e_systim_overflow_work);
 335
 336         schedule_delayed_work(&adapter->systim_overflow_work,
 337                               E1000_SYSTIM_OVERFLOW_PERIOD);
 338
 339         adapter->ptp_clock = ptp_clock_register(&adapter->ptp_clock_info,
 340                                                 &adapter->pdev->dev);
 341         if (IS_ERR(adapter->ptp_clock)) {
 342                 adapter->ptp_clock = NULL;
 343                 e_err("ptp_clock_register failed\n");
 344         } else if (adapter->ptp_clock) {
 345                 e_info("registered PHC clock\n");
 346         }
 347 }
 348
 349 /**
 350  * e1000e_ptp_remove - disable PTP device and stop the overflow check
 351  * @adapter: board private structure
 352  *
 353  * Stop the PTP support, and cancel the delayed work.
 354  **/
 355 void e1000e_ptp_remove(struct e1000_adapter *adapter)
 356 {
 357         if (!(adapter->flags & FLAG_HAS_HW_TIMESTAMP))
 358                 return;
 359
 360         cancel_delayed_work_sync(&adapter->systim_overflow_work);
 361
 362         if (adapter->ptp_clock) {
 363                 ptp_clock_unregister(adapter->ptp_clock);
 364                 adapter->ptp_clock = NULL;
 365                 e_info("removed PHC\n");
 366         }
 367 }