1 /* PTP 1588 clock using the Renesas Ethernet AVB 2 * 3 * Copyright (C) 2013-2015 Renesas Electronics Corporation 4 * Copyright (C) 2015 Renesas Solutions Corp. 5 * Copyright (C) 2015 Cogent Embedded, Inc. <source@cogentembedded.com> 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License as published by 9 * the Free Software Foundation; either version 2 of the License, or 10 * (at your option) any later version. 11 */ 12 13 #include "ravb.h" 14 15 static int ravb_ptp_tcr_request(struct ravb_private *priv, u32 request) 16 { 17 struct net_device *ndev = priv->ndev; 18 int error; 19 20 error = ravb_wait(ndev, GCCR, GCCR_TCR, GCCR_TCR_NOREQ); 21 if (error) 22 return error; 23 24 ravb_write(ndev, ravb_read(ndev, GCCR) | request, GCCR); 25 return ravb_wait(ndev, GCCR, GCCR_TCR, GCCR_TCR_NOREQ); 26 } 27 28 /* Caller must hold the lock */ 29 static int ravb_ptp_time_read(struct ravb_private *priv, struct timespec64 *ts) 30 { 31 struct net_device *ndev = priv->ndev; 32 int error; 33 34 error = ravb_ptp_tcr_request(priv, GCCR_TCR_CAPTURE); 35 if (error) 36 return error; 37 38 ts->tv_nsec = ravb_read(ndev, GCT0); 39 ts->tv_sec = ravb_read(ndev, GCT1) | 40 ((s64)ravb_read(ndev, GCT2) << 32); 41 42 return 0; 43 } 44 45 /* Caller must hold the lock */ 46 static int ravb_ptp_time_write(struct ravb_private *priv, 47 const struct timespec64 *ts) 48 { 49 struct net_device *ndev = priv->ndev; 50 int error; 51 u32 gccr; 52 53 error = ravb_ptp_tcr_request(priv, GCCR_TCR_RESET); 54 if (error) 55 return error; 56 57 gccr = ravb_read(ndev, GCCR); 58 if (gccr & GCCR_LTO) 59 return -EBUSY; 60 ravb_write(ndev, ts->tv_nsec, GTO0); 61 ravb_write(ndev, ts->tv_sec, GTO1); 62 ravb_write(ndev, (ts->tv_sec >> 32) & 0xffff, GTO2); 63 ravb_write(ndev, gccr | GCCR_LTO, GCCR); 64 65 return 0; 66 } 67 68 /* Caller must hold the lock */ 69 static int ravb_ptp_update_compare(struct ravb_private *priv, u32 ns) 70 { 71 struct net_device *ndev = priv->ndev; 72 /* When the comparison value (GPTC.PTCV) is in range of 73 * [x-1 to x+1] (x is the configured increment value in 74 * GTI.TIV), it may happen that a comparison match is 75 * not detected when the timer wraps around. 76 */ 77 u32 gti_ns_plus_1 = (priv->ptp.current_addend >> 20) + 1; 78 u32 gccr; 79 80 if (ns < gti_ns_plus_1) 81 ns = gti_ns_plus_1; 82 else if (ns > 0 - gti_ns_plus_1) 83 ns = 0 - gti_ns_plus_1; 84 85 gccr = ravb_read(ndev, GCCR); 86 if (gccr & GCCR_LPTC) 87 return -EBUSY; 88 ravb_write(ndev, ns, GPTC); 89 ravb_write(ndev, gccr | GCCR_LPTC, GCCR); 90 91 return 0; 92 } 93 94 /* PTP clock operations */ 95 static int ravb_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb) 96 { 97 struct ravb_private *priv = container_of(ptp, struct ravb_private, 98 ptp.info); 99 struct net_device *ndev = priv->ndev; 100 unsigned long flags; 101 u32 diff, addend; 102 bool neg_adj = false; 103 u32 gccr; 104 105 if (ppb < 0) { 106 neg_adj = true; 107 ppb = -ppb; 108 } 109 addend = priv->ptp.default_addend; 110 diff = div_u64((u64)addend * ppb, NSEC_PER_SEC); 111 112 addend = neg_adj ? addend - diff : addend + diff; 113 114 spin_lock_irqsave(&priv->lock, flags); 115 116 priv->ptp.current_addend = addend; 117 118 gccr = ravb_read(ndev, GCCR); 119 if (gccr & GCCR_LTI) 120 return -EBUSY; 121 ravb_write(ndev, addend & GTI_TIV, GTI); 122 ravb_write(ndev, gccr | GCCR_LTI, GCCR); 123 124 spin_unlock_irqrestore(&priv->lock, flags); 125 126 return 0; 127 } 128 129 static int ravb_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta) 130 { 131 struct ravb_private *priv = container_of(ptp, struct ravb_private, 132 ptp.info); 133 struct timespec64 ts; 134 unsigned long flags; 135 int error; 136 137 spin_lock_irqsave(&priv->lock, flags); 138 error = ravb_ptp_time_read(priv, &ts); 139 if (!error) { 140 u64 now = ktime_to_ns(timespec64_to_ktime(ts)); 141 142 ts = ns_to_timespec64(now + delta); 143 error = ravb_ptp_time_write(priv, &ts); 144 } 145 spin_unlock_irqrestore(&priv->lock, flags); 146 147 return error; 148 } 149 150 static int ravb_ptp_gettime64(struct ptp_clock_info *ptp, struct timespec64 *ts) 151 { 152 struct ravb_private *priv = container_of(ptp, struct ravb_private, 153 ptp.info); 154 unsigned long flags; 155 int error; 156 157 spin_lock_irqsave(&priv->lock, flags); 158 error = ravb_ptp_time_read(priv, ts); 159 spin_unlock_irqrestore(&priv->lock, flags); 160 161 return error; 162 } 163 164 static int ravb_ptp_settime64(struct ptp_clock_info *ptp, 165 const struct timespec64 *ts) 166 { 167 struct ravb_private *priv = container_of(ptp, struct ravb_private, 168 ptp.info); 169 unsigned long flags; 170 int error; 171 172 spin_lock_irqsave(&priv->lock, flags); 173 error = ravb_ptp_time_write(priv, ts); 174 spin_unlock_irqrestore(&priv->lock, flags); 175 176 return error; 177 } 178 179 static int ravb_ptp_extts(struct ptp_clock_info *ptp, 180 struct ptp_extts_request *req, int on) 181 { 182 struct ravb_private *priv = container_of(ptp, struct ravb_private, 183 ptp.info); 184 struct net_device *ndev = priv->ndev; 185 unsigned long flags; 186 u32 gic; 187 188 if (req->index) 189 return -EINVAL; 190 191 if (priv->ptp.extts[req->index] == on) 192 return 0; 193 priv->ptp.extts[req->index] = on; 194 195 spin_lock_irqsave(&priv->lock, flags); 196 gic = ravb_read(ndev, GIC); 197 if (on) 198 gic |= GIC_PTCE; 199 else 200 gic &= ~GIC_PTCE; 201 ravb_write(ndev, gic, GIC); 202 mmiowb(); 203 spin_unlock_irqrestore(&priv->lock, flags); 204 205 return 0; 206 } 207 208 static int ravb_ptp_perout(struct ptp_clock_info *ptp, 209 struct ptp_perout_request *req, int on) 210 { 211 struct ravb_private *priv = container_of(ptp, struct ravb_private, 212 ptp.info); 213 struct net_device *ndev = priv->ndev; 214 struct ravb_ptp_perout *perout; 215 unsigned long flags; 216 int error = 0; 217 u32 gic; 218 219 if (req->index) 220 return -EINVAL; 221 222 if (on) { 223 u64 start_ns; 224 u64 period_ns; 225 226 start_ns = req->start.sec * NSEC_PER_SEC + req->start.nsec; 227 period_ns = req->period.sec * NSEC_PER_SEC + req->period.nsec; 228 229 if (start_ns > U32_MAX) { 230 netdev_warn(ndev, 231 "ptp: start value (nsec) is over limit. Maximum size of start is only 32 bits\n"); 232 return -ERANGE; 233 } 234 235 if (period_ns > U32_MAX) { 236 netdev_warn(ndev, 237 "ptp: period value (nsec) is over limit. Maximum size of period is only 32 bits\n"); 238 return -ERANGE; 239 } 240 241 spin_lock_irqsave(&priv->lock, flags); 242 243 perout = &priv->ptp.perout[req->index]; 244 perout->target = (u32)start_ns; 245 perout->period = (u32)period_ns; 246 error = ravb_ptp_update_compare(priv, (u32)start_ns); 247 if (!error) { 248 /* Unmask interrupt */ 249 gic = ravb_read(ndev, GIC); 250 gic |= GIC_PTME; 251 ravb_write(ndev, gic, GIC); 252 } 253 } else { 254 spin_lock_irqsave(&priv->lock, flags); 255 256 perout = &priv->ptp.perout[req->index]; 257 perout->period = 0; 258 259 /* Mask interrupt */ 260 gic = ravb_read(ndev, GIC); 261 gic &= ~GIC_PTME; 262 ravb_write(ndev, gic, GIC); 263 } 264 mmiowb(); 265 spin_unlock_irqrestore(&priv->lock, flags); 266 267 return error; 268 } 269 270 static int ravb_ptp_enable(struct ptp_clock_info *ptp, 271 struct ptp_clock_request *req, int on) 272 { 273 switch (req->type) { 274 case PTP_CLK_REQ_EXTTS: 275 return ravb_ptp_extts(ptp, &req->extts, on); 276 case PTP_CLK_REQ_PEROUT: 277 return ravb_ptp_perout(ptp, &req->perout, on); 278 default: 279 return -EOPNOTSUPP; 280 } 281 } 282 283 static const struct ptp_clock_info ravb_ptp_info = { 284 .owner = THIS_MODULE, 285 .name = "ravb clock", 286 .max_adj = 50000000, 287 .n_ext_ts = N_EXT_TS, 288 .n_per_out = N_PER_OUT, 289 .adjfreq = ravb_ptp_adjfreq, 290 .adjtime = ravb_ptp_adjtime, 291 .gettime64 = ravb_ptp_gettime64, 292 .settime64 = ravb_ptp_settime64, 293 .enable = ravb_ptp_enable, 294 }; 295 296 /* Caller must hold the lock */ 297 irqreturn_t ravb_ptp_interrupt(struct net_device *ndev) 298 { 299 struct ravb_private *priv = netdev_priv(ndev); 300 u32 gis = ravb_read(ndev, GIS); 301 302 gis &= ravb_read(ndev, GIC); 303 if (gis & GIS_PTCF) { 304 struct ptp_clock_event event; 305 306 event.type = PTP_CLOCK_EXTTS; 307 event.index = 0; 308 event.timestamp = ravb_read(ndev, GCPT); 309 ptp_clock_event(priv->ptp.clock, &event); 310 } 311 if (gis & GIS_PTMF) { 312 struct ravb_ptp_perout *perout = priv->ptp.perout; 313 314 if (perout->period) { 315 perout->target += perout->period; 316 ravb_ptp_update_compare(priv, perout->target); 317 } 318 } 319 320 if (gis) { 321 ravb_write(ndev, ~gis, GIS); 322 return IRQ_HANDLED; 323 } 324 325 return IRQ_NONE; 326 } 327 328 void ravb_ptp_init(struct net_device *ndev, struct platform_device *pdev) 329 { 330 struct ravb_private *priv = netdev_priv(ndev); 331 unsigned long flags; 332 u32 gccr; 333 334 priv->ptp.info = ravb_ptp_info; 335 336 priv->ptp.default_addend = ravb_read(ndev, GTI); 337 priv->ptp.current_addend = priv->ptp.default_addend; 338 339 spin_lock_irqsave(&priv->lock, flags); 340 ravb_wait(ndev, GCCR, GCCR_TCR, GCCR_TCR_NOREQ); 341 gccr = ravb_read(ndev, GCCR) & ~GCCR_TCSS; 342 ravb_write(ndev, gccr | GCCR_TCSS_ADJGPTP, GCCR); 343 mmiowb(); 344 spin_unlock_irqrestore(&priv->lock, flags); 345 346 priv->ptp.clock = ptp_clock_register(&priv->ptp.info, &pdev->dev); 347 } 348 349 void ravb_ptp_stop(struct net_device *ndev) 350 { 351 struct ravb_private *priv = netdev_priv(ndev); 352 353 ravb_write(ndev, 0, GIC); 354 ravb_write(ndev, 0, GIS); 355 356 ptp_clock_unregister(priv->ptp.clock); 357 } 358