1 // SPDX-License-Identifier: GPL-2.0+ 2 /* PTP 1588 clock using the Renesas Ethernet AVB 3 * 4 * Copyright (C) 2013-2015 Renesas Electronics Corporation 5 * Copyright (C) 2015 Renesas Solutions Corp. 6 * Copyright (C) 2015-2016 Cogent Embedded, Inc. <source@cogentembedded.com> 7 */ 8 9 #include "ravb.h" 10 11 static int ravb_ptp_tcr_request(struct ravb_private *priv, u32 request) 12 { 13 struct net_device *ndev = priv->ndev; 14 int error; 15 16 error = ravb_wait(ndev, GCCR, GCCR_TCR, GCCR_TCR_NOREQ); 17 if (error) 18 return error; 19 20 ravb_modify(ndev, GCCR, request, request); 21 return ravb_wait(ndev, GCCR, GCCR_TCR, GCCR_TCR_NOREQ); 22 } 23 24 /* Caller must hold the lock */ 25 static int ravb_ptp_time_read(struct ravb_private *priv, struct timespec64 *ts) 26 { 27 struct net_device *ndev = priv->ndev; 28 int error; 29 30 error = ravb_ptp_tcr_request(priv, GCCR_TCR_CAPTURE); 31 if (error) 32 return error; 33 34 ts->tv_nsec = ravb_read(ndev, GCT0); 35 ts->tv_sec = ravb_read(ndev, GCT1) | 36 ((s64)ravb_read(ndev, GCT2) << 32); 37 38 return 0; 39 } 40 41 /* Caller must hold the lock */ 42 static int ravb_ptp_time_write(struct ravb_private *priv, 43 const struct timespec64 *ts) 44 { 45 struct net_device *ndev = priv->ndev; 46 int error; 47 u32 gccr; 48 49 error = ravb_ptp_tcr_request(priv, GCCR_TCR_RESET); 50 if (error) 51 return error; 52 53 gccr = ravb_read(ndev, GCCR); 54 if (gccr & GCCR_LTO) 55 return -EBUSY; 56 ravb_write(ndev, ts->tv_nsec, GTO0); 57 ravb_write(ndev, ts->tv_sec, GTO1); 58 ravb_write(ndev, (ts->tv_sec >> 32) & 0xffff, GTO2); 59 ravb_write(ndev, gccr | GCCR_LTO, GCCR); 60 61 return 0; 62 } 63 64 /* Caller must hold the lock */ 65 static int ravb_ptp_update_compare(struct ravb_private *priv, u32 ns) 66 { 67 struct net_device *ndev = priv->ndev; 68 /* When the comparison value (GPTC.PTCV) is in range of 69 * [x-1 to x+1] (x is the configured increment value in 70 * GTI.TIV), it may happen that a comparison match is 71 * not detected when the timer wraps around. 72 */ 73 u32 gti_ns_plus_1 = (priv->ptp.current_addend >> 20) + 1; 74 u32 gccr; 75 76 if (ns < gti_ns_plus_1) 77 ns = gti_ns_plus_1; 78 else if (ns > 0 - gti_ns_plus_1) 79 ns = 0 - gti_ns_plus_1; 80 81 gccr = ravb_read(ndev, GCCR); 82 if (gccr & GCCR_LPTC) 83 return -EBUSY; 84 ravb_write(ndev, ns, GPTC); 85 ravb_write(ndev, gccr | GCCR_LPTC, GCCR); 86 87 return 0; 88 } 89 90 /* PTP clock operations */ 91 static int ravb_ptp_adjfreq(struct ptp_clock_info *ptp, s32 ppb) 92 { 93 struct ravb_private *priv = container_of(ptp, struct ravb_private, 94 ptp.info); 95 struct net_device *ndev = priv->ndev; 96 unsigned long flags; 97 u32 diff, addend; 98 bool neg_adj = false; 99 u32 gccr; 100 101 if (ppb < 0) { 102 neg_adj = true; 103 ppb = -ppb; 104 } 105 addend = priv->ptp.default_addend; 106 diff = div_u64((u64)addend * ppb, NSEC_PER_SEC); 107 108 addend = neg_adj ? addend - diff : addend + diff; 109 110 spin_lock_irqsave(&priv->lock, flags); 111 112 priv->ptp.current_addend = addend; 113 114 gccr = ravb_read(ndev, GCCR); 115 if (gccr & GCCR_LTI) { 116 spin_unlock_irqrestore(&priv->lock, flags); 117 return -EBUSY; 118 } 119 ravb_write(ndev, addend & GTI_TIV, GTI); 120 ravb_write(ndev, gccr | GCCR_LTI, GCCR); 121 122 spin_unlock_irqrestore(&priv->lock, flags); 123 124 return 0; 125 } 126 127 static int ravb_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta) 128 { 129 struct ravb_private *priv = container_of(ptp, struct ravb_private, 130 ptp.info); 131 struct timespec64 ts; 132 unsigned long flags; 133 int error; 134 135 spin_lock_irqsave(&priv->lock, flags); 136 error = ravb_ptp_time_read(priv, &ts); 137 if (!error) { 138 u64 now = ktime_to_ns(timespec64_to_ktime(ts)); 139 140 ts = ns_to_timespec64(now + delta); 141 error = ravb_ptp_time_write(priv, &ts); 142 } 143 spin_unlock_irqrestore(&priv->lock, flags); 144 145 return error; 146 } 147 148 static int ravb_ptp_gettime64(struct ptp_clock_info *ptp, struct timespec64 *ts) 149 { 150 struct ravb_private *priv = container_of(ptp, struct ravb_private, 151 ptp.info); 152 unsigned long flags; 153 int error; 154 155 spin_lock_irqsave(&priv->lock, flags); 156 error = ravb_ptp_time_read(priv, ts); 157 spin_unlock_irqrestore(&priv->lock, flags); 158 159 return error; 160 } 161 162 static int ravb_ptp_settime64(struct ptp_clock_info *ptp, 163 const struct timespec64 *ts) 164 { 165 struct ravb_private *priv = container_of(ptp, struct ravb_private, 166 ptp.info); 167 unsigned long flags; 168 int error; 169 170 spin_lock_irqsave(&priv->lock, flags); 171 error = ravb_ptp_time_write(priv, ts); 172 spin_unlock_irqrestore(&priv->lock, flags); 173 174 return error; 175 } 176 177 static int ravb_ptp_extts(struct ptp_clock_info *ptp, 178 struct ptp_extts_request *req, int on) 179 { 180 struct ravb_private *priv = container_of(ptp, struct ravb_private, 181 ptp.info); 182 struct net_device *ndev = priv->ndev; 183 unsigned long flags; 184 185 if (req->index) 186 return -EINVAL; 187 188 if (priv->ptp.extts[req->index] == on) 189 return 0; 190 priv->ptp.extts[req->index] = on; 191 192 spin_lock_irqsave(&priv->lock, flags); 193 if (priv->chip_id == RCAR_GEN2) 194 ravb_modify(ndev, GIC, GIC_PTCE, on ? GIC_PTCE : 0); 195 else if (on) 196 ravb_write(ndev, GIE_PTCS, GIE); 197 else 198 ravb_write(ndev, GID_PTCD, GID); 199 spin_unlock_irqrestore(&priv->lock, flags); 200 201 return 0; 202 } 203 204 static int ravb_ptp_perout(struct ptp_clock_info *ptp, 205 struct ptp_perout_request *req, int on) 206 { 207 struct ravb_private *priv = container_of(ptp, struct ravb_private, 208 ptp.info); 209 struct net_device *ndev = priv->ndev; 210 struct ravb_ptp_perout *perout; 211 unsigned long flags; 212 int error = 0; 213 214 if (req->index) 215 return -EINVAL; 216 217 if (on) { 218 u64 start_ns; 219 u64 period_ns; 220 221 start_ns = req->start.sec * NSEC_PER_SEC + req->start.nsec; 222 period_ns = req->period.sec * NSEC_PER_SEC + req->period.nsec; 223 224 if (start_ns > U32_MAX) { 225 netdev_warn(ndev, 226 "ptp: start value (nsec) is over limit. Maximum size of start is only 32 bits\n"); 227 return -ERANGE; 228 } 229 230 if (period_ns > U32_MAX) { 231 netdev_warn(ndev, 232 "ptp: period value (nsec) is over limit. Maximum size of period is only 32 bits\n"); 233 return -ERANGE; 234 } 235 236 spin_lock_irqsave(&priv->lock, flags); 237 238 perout = &priv->ptp.perout[req->index]; 239 perout->target = (u32)start_ns; 240 perout->period = (u32)period_ns; 241 error = ravb_ptp_update_compare(priv, (u32)start_ns); 242 if (!error) { 243 /* Unmask interrupt */ 244 if (priv->chip_id == RCAR_GEN2) 245 ravb_modify(ndev, GIC, GIC_PTME, GIC_PTME); 246 else 247 ravb_write(ndev, GIE_PTMS0, GIE); 248 } 249 } else { 250 spin_lock_irqsave(&priv->lock, flags); 251 252 perout = &priv->ptp.perout[req->index]; 253 perout->period = 0; 254 255 /* Mask interrupt */ 256 if (priv->chip_id == RCAR_GEN2) 257 ravb_modify(ndev, GIC, GIC_PTME, 0); 258 else 259 ravb_write(ndev, GID_PTMD0, GID); 260 } 261 spin_unlock_irqrestore(&priv->lock, flags); 262 263 return error; 264 } 265 266 static int ravb_ptp_enable(struct ptp_clock_info *ptp, 267 struct ptp_clock_request *req, int on) 268 { 269 switch (req->type) { 270 case PTP_CLK_REQ_EXTTS: 271 return ravb_ptp_extts(ptp, &req->extts, on); 272 case PTP_CLK_REQ_PEROUT: 273 return ravb_ptp_perout(ptp, &req->perout, on); 274 default: 275 return -EOPNOTSUPP; 276 } 277 } 278 279 static const struct ptp_clock_info ravb_ptp_info = { 280 .owner = THIS_MODULE, 281 .name = "ravb clock", 282 .max_adj = 50000000, 283 .n_ext_ts = N_EXT_TS, 284 .n_per_out = N_PER_OUT, 285 .adjfreq = ravb_ptp_adjfreq, 286 .adjtime = ravb_ptp_adjtime, 287 .gettime64 = ravb_ptp_gettime64, 288 .settime64 = ravb_ptp_settime64, 289 .enable = ravb_ptp_enable, 290 }; 291 292 /* Caller must hold the lock */ 293 void ravb_ptp_interrupt(struct net_device *ndev) 294 { 295 struct ravb_private *priv = netdev_priv(ndev); 296 u32 gis = ravb_read(ndev, GIS); 297 298 gis &= ravb_read(ndev, GIC); 299 if (gis & GIS_PTCF) { 300 struct ptp_clock_event event; 301 302 event.type = PTP_CLOCK_EXTTS; 303 event.index = 0; 304 event.timestamp = ravb_read(ndev, GCPT); 305 ptp_clock_event(priv->ptp.clock, &event); 306 } 307 if (gis & GIS_PTMF) { 308 struct ravb_ptp_perout *perout = priv->ptp.perout; 309 310 if (perout->period) { 311 perout->target += perout->period; 312 ravb_ptp_update_compare(priv, perout->target); 313 } 314 } 315 316 ravb_write(ndev, ~(gis | GIS_RESERVED), GIS); 317 } 318 319 void ravb_ptp_init(struct net_device *ndev, struct platform_device *pdev) 320 { 321 struct ravb_private *priv = netdev_priv(ndev); 322 unsigned long flags; 323 324 priv->ptp.info = ravb_ptp_info; 325 326 priv->ptp.default_addend = ravb_read(ndev, GTI); 327 priv->ptp.current_addend = priv->ptp.default_addend; 328 329 spin_lock_irqsave(&priv->lock, flags); 330 ravb_wait(ndev, GCCR, GCCR_TCR, GCCR_TCR_NOREQ); 331 ravb_modify(ndev, GCCR, GCCR_TCSS, GCCR_TCSS_ADJGPTP); 332 spin_unlock_irqrestore(&priv->lock, flags); 333 334 priv->ptp.clock = ptp_clock_register(&priv->ptp.info, &pdev->dev); 335 } 336 337 void ravb_ptp_stop(struct net_device *ndev) 338 { 339 struct ravb_private *priv = netdev_priv(ndev); 340 341 ravb_write(ndev, 0, GIC); 342 ravb_write(ndev, 0, GIS); 343 344 ptp_clock_unregister(priv->ptp.clock); 345 } 346