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) 2015-2016 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_modify(ndev, GCCR, request, request); 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 spin_unlock_irqrestore(&priv->lock, flags); 121 return -EBUSY; 122 } 123 ravb_write(ndev, addend & GTI_TIV, GTI); 124 ravb_write(ndev, gccr | GCCR_LTI, GCCR); 125 126 spin_unlock_irqrestore(&priv->lock, flags); 127 128 return 0; 129 } 130 131 static int ravb_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta) 132 { 133 struct ravb_private *priv = container_of(ptp, struct ravb_private, 134 ptp.info); 135 struct timespec64 ts; 136 unsigned long flags; 137 int error; 138 139 spin_lock_irqsave(&priv->lock, flags); 140 error = ravb_ptp_time_read(priv, &ts); 141 if (!error) { 142 u64 now = ktime_to_ns(timespec64_to_ktime(ts)); 143 144 ts = ns_to_timespec64(now + delta); 145 error = ravb_ptp_time_write(priv, &ts); 146 } 147 spin_unlock_irqrestore(&priv->lock, flags); 148 149 return error; 150 } 151 152 static int ravb_ptp_gettime64(struct ptp_clock_info *ptp, struct timespec64 *ts) 153 { 154 struct ravb_private *priv = container_of(ptp, struct ravb_private, 155 ptp.info); 156 unsigned long flags; 157 int error; 158 159 spin_lock_irqsave(&priv->lock, flags); 160 error = ravb_ptp_time_read(priv, ts); 161 spin_unlock_irqrestore(&priv->lock, flags); 162 163 return error; 164 } 165 166 static int ravb_ptp_settime64(struct ptp_clock_info *ptp, 167 const struct timespec64 *ts) 168 { 169 struct ravb_private *priv = container_of(ptp, struct ravb_private, 170 ptp.info); 171 unsigned long flags; 172 int error; 173 174 spin_lock_irqsave(&priv->lock, flags); 175 error = ravb_ptp_time_write(priv, ts); 176 spin_unlock_irqrestore(&priv->lock, flags); 177 178 return error; 179 } 180 181 static int ravb_ptp_extts(struct ptp_clock_info *ptp, 182 struct ptp_extts_request *req, int on) 183 { 184 struct ravb_private *priv = container_of(ptp, struct ravb_private, 185 ptp.info); 186 struct net_device *ndev = priv->ndev; 187 unsigned long flags; 188 189 if (req->index) 190 return -EINVAL; 191 192 if (priv->ptp.extts[req->index] == on) 193 return 0; 194 priv->ptp.extts[req->index] = on; 195 196 spin_lock_irqsave(&priv->lock, flags); 197 if (priv->chip_id == RCAR_GEN2) 198 ravb_modify(ndev, GIC, GIC_PTCE, on ? GIC_PTCE : 0); 199 else if (on) 200 ravb_write(ndev, GIE_PTCS, GIE); 201 else 202 ravb_write(ndev, GID_PTCD, GID); 203 mmiowb(); 204 spin_unlock_irqrestore(&priv->lock, flags); 205 206 return 0; 207 } 208 209 static int ravb_ptp_perout(struct ptp_clock_info *ptp, 210 struct ptp_perout_request *req, int on) 211 { 212 struct ravb_private *priv = container_of(ptp, struct ravb_private, 213 ptp.info); 214 struct net_device *ndev = priv->ndev; 215 struct ravb_ptp_perout *perout; 216 unsigned long flags; 217 int error = 0; 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 if (priv->chip_id == RCAR_GEN2) 250 ravb_modify(ndev, GIC, GIC_PTME, GIC_PTME); 251 else 252 ravb_write(ndev, GIE_PTMS0, GIE); 253 } 254 } else { 255 spin_lock_irqsave(&priv->lock, flags); 256 257 perout = &priv->ptp.perout[req->index]; 258 perout->period = 0; 259 260 /* Mask interrupt */ 261 if (priv->chip_id == RCAR_GEN2) 262 ravb_modify(ndev, GIC, GIC_PTME, 0); 263 else 264 ravb_write(ndev, GID_PTMD0, GID); 265 } 266 mmiowb(); 267 spin_unlock_irqrestore(&priv->lock, flags); 268 269 return error; 270 } 271 272 static int ravb_ptp_enable(struct ptp_clock_info *ptp, 273 struct ptp_clock_request *req, int on) 274 { 275 switch (req->type) { 276 case PTP_CLK_REQ_EXTTS: 277 return ravb_ptp_extts(ptp, &req->extts, on); 278 case PTP_CLK_REQ_PEROUT: 279 return ravb_ptp_perout(ptp, &req->perout, on); 280 default: 281 return -EOPNOTSUPP; 282 } 283 } 284 285 static const struct ptp_clock_info ravb_ptp_info = { 286 .owner = THIS_MODULE, 287 .name = "ravb clock", 288 .max_adj = 50000000, 289 .n_ext_ts = N_EXT_TS, 290 .n_per_out = N_PER_OUT, 291 .adjfreq = ravb_ptp_adjfreq, 292 .adjtime = ravb_ptp_adjtime, 293 .gettime64 = ravb_ptp_gettime64, 294 .settime64 = ravb_ptp_settime64, 295 .enable = ravb_ptp_enable, 296 }; 297 298 /* Caller must hold the lock */ 299 void ravb_ptp_interrupt(struct net_device *ndev) 300 { 301 struct ravb_private *priv = netdev_priv(ndev); 302 u32 gis = ravb_read(ndev, GIS); 303 304 gis &= ravb_read(ndev, GIC); 305 if (gis & GIS_PTCF) { 306 struct ptp_clock_event event; 307 308 event.type = PTP_CLOCK_EXTTS; 309 event.index = 0; 310 event.timestamp = ravb_read(ndev, GCPT); 311 ptp_clock_event(priv->ptp.clock, &event); 312 } 313 if (gis & GIS_PTMF) { 314 struct ravb_ptp_perout *perout = priv->ptp.perout; 315 316 if (perout->period) { 317 perout->target += perout->period; 318 ravb_ptp_update_compare(priv, perout->target); 319 } 320 } 321 322 ravb_write(ndev, ~gis, GIS); 323 } 324 325 void ravb_ptp_init(struct net_device *ndev, struct platform_device *pdev) 326 { 327 struct ravb_private *priv = netdev_priv(ndev); 328 unsigned long flags; 329 330 priv->ptp.info = ravb_ptp_info; 331 332 priv->ptp.default_addend = ravb_read(ndev, GTI); 333 priv->ptp.current_addend = priv->ptp.default_addend; 334 335 spin_lock_irqsave(&priv->lock, flags); 336 ravb_wait(ndev, GCCR, GCCR_TCR, GCCR_TCR_NOREQ); 337 ravb_modify(ndev, GCCR, GCCR_TCSS, GCCR_TCSS_ADJGPTP); 338 mmiowb(); 339 spin_unlock_irqrestore(&priv->lock, flags); 340 341 priv->ptp.clock = ptp_clock_register(&priv->ptp.info, &pdev->dev); 342 } 343 344 void ravb_ptp_stop(struct net_device *ndev) 345 { 346 struct ravb_private *priv = netdev_priv(ndev); 347 348 ravb_write(ndev, 0, GIC); 349 ravb_write(ndev, 0, GIS); 350 351 ptp_clock_unregister(priv->ptp.clock); 352 } 353