1 // SPDX-License-Identifier: GPL-2.0 2 3 /* Copyright (c) 2014-2018, The Linux Foundation. All rights reserved. 4 * Copyright (C) 2018-2021 Linaro Ltd. 5 */ 6 7 #include <linux/errno.h> 8 #include <linux/if_arp.h> 9 #include <linux/netdevice.h> 10 #include <linux/skbuff.h> 11 #include <linux/if_rmnet.h> 12 #include <linux/etherdevice.h> 13 #include <net/pkt_sched.h> 14 #include <linux/pm_runtime.h> 15 #include <linux/remoteproc/qcom_rproc.h> 16 17 #include "ipa.h" 18 #include "ipa_data.h" 19 #include "ipa_endpoint.h" 20 #include "ipa_table.h" 21 #include "ipa_mem.h" 22 #include "ipa_modem.h" 23 #include "ipa_smp2p.h" 24 #include "ipa_qmi.h" 25 #include "ipa_uc.h" 26 #include "ipa_power.h" 27 28 #define IPA_NETDEV_NAME "rmnet_ipa%d" 29 #define IPA_NETDEV_TAILROOM 0 /* for padding by mux layer */ 30 #define IPA_NETDEV_TIMEOUT 10 /* seconds */ 31 32 enum ipa_modem_state { 33 IPA_MODEM_STATE_STOPPED = 0, 34 IPA_MODEM_STATE_STARTING, 35 IPA_MODEM_STATE_RUNNING, 36 IPA_MODEM_STATE_STOPPING, 37 }; 38 39 /** 40 * struct ipa_priv - IPA network device private data 41 * @ipa: IPA pointer 42 * @work: Work structure used to wake the modem netdev TX queue 43 */ 44 struct ipa_priv { 45 struct ipa *ipa; 46 struct work_struct work; 47 }; 48 49 /** ipa_open() - Opens the modem network interface */ 50 static int ipa_open(struct net_device *netdev) 51 { 52 struct ipa_priv *priv = netdev_priv(netdev); 53 struct ipa *ipa = priv->ipa; 54 struct device *dev; 55 int ret; 56 57 dev = &ipa->pdev->dev; 58 ret = pm_runtime_get_sync(dev); 59 if (ret < 0) 60 goto err_power_put; 61 62 ret = ipa_endpoint_enable_one(ipa->name_map[IPA_ENDPOINT_AP_MODEM_TX]); 63 if (ret) 64 goto err_power_put; 65 66 ret = ipa_endpoint_enable_one(ipa->name_map[IPA_ENDPOINT_AP_MODEM_RX]); 67 if (ret) 68 goto err_disable_tx; 69 70 netif_start_queue(netdev); 71 72 pm_runtime_mark_last_busy(dev); 73 (void)pm_runtime_put_autosuspend(dev); 74 75 return 0; 76 77 err_disable_tx: 78 ipa_endpoint_disable_one(ipa->name_map[IPA_ENDPOINT_AP_MODEM_TX]); 79 err_power_put: 80 pm_runtime_put_noidle(dev); 81 82 return ret; 83 } 84 85 /** ipa_stop() - Stops the modem network interface. */ 86 static int ipa_stop(struct net_device *netdev) 87 { 88 struct ipa_priv *priv = netdev_priv(netdev); 89 struct ipa *ipa = priv->ipa; 90 struct device *dev; 91 int ret; 92 93 dev = &ipa->pdev->dev; 94 ret = pm_runtime_get_sync(dev); 95 if (ret < 0) 96 goto out_power_put; 97 98 netif_stop_queue(netdev); 99 100 ipa_endpoint_disable_one(ipa->name_map[IPA_ENDPOINT_AP_MODEM_RX]); 101 ipa_endpoint_disable_one(ipa->name_map[IPA_ENDPOINT_AP_MODEM_TX]); 102 out_power_put: 103 pm_runtime_mark_last_busy(dev); 104 (void)pm_runtime_put_autosuspend(dev); 105 106 return 0; 107 } 108 109 /** ipa_start_xmit() - Transmits an skb. 110 * @skb: skb to be transmitted 111 * @dev: network device 112 * 113 * Return codes: 114 * NETDEV_TX_OK: Success 115 * NETDEV_TX_BUSY: Error while transmitting the skb. Try again later 116 */ 117 static netdev_tx_t 118 ipa_start_xmit(struct sk_buff *skb, struct net_device *netdev) 119 { 120 struct net_device_stats *stats = &netdev->stats; 121 struct ipa_priv *priv = netdev_priv(netdev); 122 struct ipa_endpoint *endpoint; 123 struct ipa *ipa = priv->ipa; 124 u32 skb_len = skb->len; 125 struct device *dev; 126 int ret; 127 128 if (!skb_len) 129 goto err_drop_skb; 130 131 endpoint = ipa->name_map[IPA_ENDPOINT_AP_MODEM_TX]; 132 if (endpoint->config.qmap && skb->protocol != htons(ETH_P_MAP)) 133 goto err_drop_skb; 134 135 /* The hardware must be powered for us to transmit */ 136 dev = &ipa->pdev->dev; 137 ret = pm_runtime_get(dev); 138 if (ret < 1) { 139 /* If a resume won't happen, just drop the packet */ 140 if (ret < 0 && ret != -EINPROGRESS) { 141 ipa_power_modem_queue_active(ipa); 142 pm_runtime_put_noidle(dev); 143 goto err_drop_skb; 144 } 145 146 /* No power (yet). Stop the network stack from transmitting 147 * until we're resumed; ipa_modem_resume() arranges for the 148 * TX queue to be started again. 149 */ 150 ipa_power_modem_queue_stop(ipa); 151 152 pm_runtime_put_noidle(dev); 153 154 return NETDEV_TX_BUSY; 155 } 156 157 ipa_power_modem_queue_active(ipa); 158 159 ret = ipa_endpoint_skb_tx(endpoint, skb); 160 161 pm_runtime_mark_last_busy(dev); 162 (void)pm_runtime_put_autosuspend(dev); 163 164 if (ret) { 165 if (ret != -E2BIG) 166 return NETDEV_TX_BUSY; 167 goto err_drop_skb; 168 } 169 170 stats->tx_packets++; 171 stats->tx_bytes += skb_len; 172 173 return NETDEV_TX_OK; 174 175 err_drop_skb: 176 dev_kfree_skb_any(skb); 177 stats->tx_dropped++; 178 179 return NETDEV_TX_OK; 180 } 181 182 void ipa_modem_skb_rx(struct net_device *netdev, struct sk_buff *skb) 183 { 184 struct net_device_stats *stats = &netdev->stats; 185 186 if (skb) { 187 skb->dev = netdev; 188 skb->protocol = htons(ETH_P_MAP); 189 stats->rx_packets++; 190 stats->rx_bytes += skb->len; 191 192 (void)netif_receive_skb(skb); 193 } else { 194 stats->rx_dropped++; 195 } 196 } 197 198 static const struct net_device_ops ipa_modem_ops = { 199 .ndo_open = ipa_open, 200 .ndo_stop = ipa_stop, 201 .ndo_start_xmit = ipa_start_xmit, 202 }; 203 204 /** ipa_modem_netdev_setup() - netdev setup function for the modem */ 205 static void ipa_modem_netdev_setup(struct net_device *netdev) 206 { 207 netdev->netdev_ops = &ipa_modem_ops; 208 209 netdev->header_ops = NULL; 210 netdev->type = ARPHRD_RAWIP; 211 netdev->hard_header_len = 0; 212 netdev->min_header_len = ETH_HLEN; 213 netdev->min_mtu = ETH_MIN_MTU; 214 netdev->max_mtu = IPA_MTU; 215 netdev->mtu = netdev->max_mtu; 216 netdev->addr_len = 0; 217 netdev->tx_queue_len = DEFAULT_TX_QUEUE_LEN; 218 netdev->flags &= ~(IFF_BROADCAST | IFF_MULTICAST); 219 netdev->priv_flags |= IFF_TX_SKB_SHARING; 220 eth_broadcast_addr(netdev->broadcast); 221 222 /* The endpoint is configured for QMAP */ 223 netdev->needed_headroom = sizeof(struct rmnet_map_header); 224 netdev->needed_tailroom = IPA_NETDEV_TAILROOM; 225 netdev->watchdog_timeo = IPA_NETDEV_TIMEOUT * HZ; 226 netdev->hw_features = NETIF_F_SG; 227 } 228 229 /** ipa_modem_suspend() - suspend callback 230 * @netdev: Network device 231 * 232 * Suspend the modem's endpoints. 233 */ 234 void ipa_modem_suspend(struct net_device *netdev) 235 { 236 struct ipa_priv *priv = netdev_priv(netdev); 237 struct ipa *ipa = priv->ipa; 238 239 if (!(netdev->flags & IFF_UP)) 240 return; 241 242 ipa_endpoint_suspend_one(ipa->name_map[IPA_ENDPOINT_AP_MODEM_RX]); 243 ipa_endpoint_suspend_one(ipa->name_map[IPA_ENDPOINT_AP_MODEM_TX]); 244 } 245 246 /** 247 * ipa_modem_wake_queue_work() - enable modem netdev queue 248 * @work: Work structure 249 * 250 * Re-enable transmit on the modem network device. This is called 251 * in (power management) work queue context, scheduled when resuming 252 * the modem. We can't enable the queue directly in ipa_modem_resume() 253 * because transmits restart the instant the queue is awakened; but the 254 * device power state won't be ACTIVE until *after* ipa_modem_resume() 255 * returns. 256 */ 257 static void ipa_modem_wake_queue_work(struct work_struct *work) 258 { 259 struct ipa_priv *priv = container_of(work, struct ipa_priv, work); 260 261 ipa_power_modem_queue_wake(priv->ipa); 262 } 263 264 /** ipa_modem_resume() - resume callback for runtime_pm 265 * @dev: pointer to device 266 * 267 * Resume the modem's endpoints. 268 */ 269 void ipa_modem_resume(struct net_device *netdev) 270 { 271 struct ipa_priv *priv = netdev_priv(netdev); 272 struct ipa *ipa = priv->ipa; 273 274 if (!(netdev->flags & IFF_UP)) 275 return; 276 277 ipa_endpoint_resume_one(ipa->name_map[IPA_ENDPOINT_AP_MODEM_TX]); 278 ipa_endpoint_resume_one(ipa->name_map[IPA_ENDPOINT_AP_MODEM_RX]); 279 280 /* Arrange for the TX queue to be restarted */ 281 (void)queue_pm_work(&priv->work); 282 } 283 284 int ipa_modem_start(struct ipa *ipa) 285 { 286 enum ipa_modem_state state; 287 struct net_device *netdev; 288 struct ipa_priv *priv; 289 int ret; 290 291 /* Only attempt to start the modem if it's stopped */ 292 state = atomic_cmpxchg(&ipa->modem_state, IPA_MODEM_STATE_STOPPED, 293 IPA_MODEM_STATE_STARTING); 294 295 /* Silently ignore attempts when running, or when changing state */ 296 if (state != IPA_MODEM_STATE_STOPPED) 297 return 0; 298 299 netdev = alloc_netdev(sizeof(struct ipa_priv), IPA_NETDEV_NAME, 300 NET_NAME_UNKNOWN, ipa_modem_netdev_setup); 301 if (!netdev) { 302 ret = -ENOMEM; 303 goto out_set_state; 304 } 305 306 SET_NETDEV_DEV(netdev, &ipa->pdev->dev); 307 priv = netdev_priv(netdev); 308 priv->ipa = ipa; 309 INIT_WORK(&priv->work, ipa_modem_wake_queue_work); 310 ipa->name_map[IPA_ENDPOINT_AP_MODEM_TX]->netdev = netdev; 311 ipa->name_map[IPA_ENDPOINT_AP_MODEM_RX]->netdev = netdev; 312 ipa->modem_netdev = netdev; 313 314 ret = register_netdev(netdev); 315 if (ret) { 316 ipa->modem_netdev = NULL; 317 ipa->name_map[IPA_ENDPOINT_AP_MODEM_RX]->netdev = NULL; 318 ipa->name_map[IPA_ENDPOINT_AP_MODEM_TX]->netdev = NULL; 319 free_netdev(netdev); 320 } 321 322 out_set_state: 323 if (ret) 324 atomic_set(&ipa->modem_state, IPA_MODEM_STATE_STOPPED); 325 else 326 atomic_set(&ipa->modem_state, IPA_MODEM_STATE_RUNNING); 327 smp_mb__after_atomic(); 328 329 return ret; 330 } 331 332 int ipa_modem_stop(struct ipa *ipa) 333 { 334 struct net_device *netdev = ipa->modem_netdev; 335 enum ipa_modem_state state; 336 337 /* Only attempt to stop the modem if it's running */ 338 state = atomic_cmpxchg(&ipa->modem_state, IPA_MODEM_STATE_RUNNING, 339 IPA_MODEM_STATE_STOPPING); 340 341 /* Silently ignore attempts when already stopped */ 342 if (state == IPA_MODEM_STATE_STOPPED) 343 return 0; 344 345 /* If we're somewhere between stopped and starting, we're busy */ 346 if (state != IPA_MODEM_STATE_RUNNING) 347 return -EBUSY; 348 349 /* Clean up the netdev and endpoints if it was started */ 350 if (netdev) { 351 struct ipa_priv *priv = netdev_priv(netdev); 352 353 cancel_work_sync(&priv->work); 354 /* If it was opened, stop it first */ 355 if (netdev->flags & IFF_UP) 356 (void)ipa_stop(netdev); 357 unregister_netdev(netdev); 358 ipa->modem_netdev = NULL; 359 ipa->name_map[IPA_ENDPOINT_AP_MODEM_RX]->netdev = NULL; 360 ipa->name_map[IPA_ENDPOINT_AP_MODEM_TX]->netdev = NULL; 361 free_netdev(netdev); 362 } 363 364 atomic_set(&ipa->modem_state, IPA_MODEM_STATE_STOPPED); 365 smp_mb__after_atomic(); 366 367 return 0; 368 } 369 370 /* Treat a "clean" modem stop the same as a crash */ 371 static void ipa_modem_crashed(struct ipa *ipa) 372 { 373 struct device *dev = &ipa->pdev->dev; 374 int ret; 375 376 /* Prevent the modem from triggering a call to ipa_setup() */ 377 ipa_smp2p_irq_disable_setup(ipa); 378 379 ret = pm_runtime_get_sync(dev); 380 if (ret < 0) { 381 dev_err(dev, "error %d getting power to handle crash\n", ret); 382 goto out_power_put; 383 } 384 385 ipa_endpoint_modem_pause_all(ipa, true); 386 387 ipa_endpoint_modem_hol_block_clear_all(ipa); 388 389 ipa_table_reset(ipa, true); 390 391 ret = ipa_table_hash_flush(ipa); 392 if (ret) 393 dev_err(dev, "error %d flushing hash caches\n", ret); 394 395 ret = ipa_endpoint_modem_exception_reset_all(ipa); 396 if (ret) 397 dev_err(dev, "error %d resetting exception endpoint\n", ret); 398 399 ipa_endpoint_modem_pause_all(ipa, false); 400 401 ret = ipa_modem_stop(ipa); 402 if (ret) 403 dev_err(dev, "error %d stopping modem\n", ret); 404 405 /* Now prepare for the next modem boot */ 406 ret = ipa_mem_zero_modem(ipa); 407 if (ret) 408 dev_err(dev, "error %d zeroing modem memory regions\n", ret); 409 410 out_power_put: 411 pm_runtime_mark_last_busy(dev); 412 (void)pm_runtime_put_autosuspend(dev); 413 } 414 415 static int ipa_modem_notify(struct notifier_block *nb, unsigned long action, 416 void *data) 417 { 418 struct ipa *ipa = container_of(nb, struct ipa, nb); 419 struct qcom_ssr_notify_data *notify_data = data; 420 struct device *dev = &ipa->pdev->dev; 421 422 switch (action) { 423 case QCOM_SSR_BEFORE_POWERUP: 424 dev_info(dev, "received modem starting event\n"); 425 ipa_uc_power(ipa); 426 ipa_smp2p_notify_reset(ipa); 427 break; 428 429 case QCOM_SSR_AFTER_POWERUP: 430 dev_info(dev, "received modem running event\n"); 431 break; 432 433 case QCOM_SSR_BEFORE_SHUTDOWN: 434 dev_info(dev, "received modem %s event\n", 435 notify_data->crashed ? "crashed" : "stopping"); 436 if (ipa->setup_complete) 437 ipa_modem_crashed(ipa); 438 break; 439 440 case QCOM_SSR_AFTER_SHUTDOWN: 441 dev_info(dev, "received modem offline event\n"); 442 break; 443 444 default: 445 dev_err(dev, "received unrecognized event %lu\n", action); 446 break; 447 } 448 449 return NOTIFY_OK; 450 } 451 452 int ipa_modem_config(struct ipa *ipa) 453 { 454 void *notifier; 455 456 ipa->nb.notifier_call = ipa_modem_notify; 457 458 notifier = qcom_register_ssr_notifier("mpss", &ipa->nb); 459 if (IS_ERR(notifier)) 460 return PTR_ERR(notifier); 461 462 ipa->notifier = notifier; 463 464 return 0; 465 } 466 467 void ipa_modem_deconfig(struct ipa *ipa) 468 { 469 struct device *dev = &ipa->pdev->dev; 470 int ret; 471 472 ret = qcom_unregister_ssr_notifier(ipa->notifier, &ipa->nb); 473 if (ret) 474 dev_err(dev, "error %d unregistering notifier", ret); 475 476 ipa->notifier = NULL; 477 memset(&ipa->nb, 0, sizeof(ipa->nb)); 478 } 479