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/remoteproc/qcom_rproc.h> 13 14 #include "ipa.h" 15 #include "ipa_data.h" 16 #include "ipa_endpoint.h" 17 #include "ipa_table.h" 18 #include "ipa_mem.h" 19 #include "ipa_modem.h" 20 #include "ipa_smp2p.h" 21 #include "ipa_qmi.h" 22 #include "ipa_uc.h" 23 24 #define IPA_NETDEV_NAME "rmnet_ipa%d" 25 #define IPA_NETDEV_TAILROOM 0 /* for padding by mux layer */ 26 #define IPA_NETDEV_TIMEOUT 10 /* seconds */ 27 28 enum ipa_modem_state { 29 IPA_MODEM_STATE_STOPPED = 0, 30 IPA_MODEM_STATE_STARTING, 31 IPA_MODEM_STATE_RUNNING, 32 IPA_MODEM_STATE_STOPPING, 33 }; 34 35 /** struct ipa_priv - IPA network device private data */ 36 struct ipa_priv { 37 struct ipa *ipa; 38 }; 39 40 /** ipa_open() - Opens the modem network interface */ 41 static int ipa_open(struct net_device *netdev) 42 { 43 struct ipa_priv *priv = netdev_priv(netdev); 44 struct ipa *ipa = priv->ipa; 45 int ret; 46 47 ret = ipa_endpoint_enable_one(ipa->name_map[IPA_ENDPOINT_AP_MODEM_TX]); 48 if (ret) 49 return ret; 50 ret = ipa_endpoint_enable_one(ipa->name_map[IPA_ENDPOINT_AP_MODEM_RX]); 51 if (ret) 52 goto err_disable_tx; 53 54 netif_start_queue(netdev); 55 56 return 0; 57 58 err_disable_tx: 59 ipa_endpoint_disable_one(ipa->name_map[IPA_ENDPOINT_AP_MODEM_TX]); 60 61 return ret; 62 } 63 64 /** ipa_stop() - Stops the modem network interface. */ 65 static int ipa_stop(struct net_device *netdev) 66 { 67 struct ipa_priv *priv = netdev_priv(netdev); 68 struct ipa *ipa = priv->ipa; 69 70 netif_stop_queue(netdev); 71 72 ipa_endpoint_disable_one(ipa->name_map[IPA_ENDPOINT_AP_MODEM_RX]); 73 ipa_endpoint_disable_one(ipa->name_map[IPA_ENDPOINT_AP_MODEM_TX]); 74 75 return 0; 76 } 77 78 /** ipa_start_xmit() - Transmits an skb. 79 * @skb: skb to be transmitted 80 * @dev: network device 81 * 82 * Return codes: 83 * NETDEV_TX_OK: Success 84 * NETDEV_TX_BUSY: Error while transmitting the skb. Try again later 85 */ 86 static int ipa_start_xmit(struct sk_buff *skb, struct net_device *netdev) 87 { 88 struct net_device_stats *stats = &netdev->stats; 89 struct ipa_priv *priv = netdev_priv(netdev); 90 struct ipa_endpoint *endpoint; 91 struct ipa *ipa = priv->ipa; 92 u32 skb_len = skb->len; 93 int ret; 94 95 if (!skb_len) 96 goto err_drop_skb; 97 98 endpoint = ipa->name_map[IPA_ENDPOINT_AP_MODEM_TX]; 99 if (endpoint->data->qmap && skb->protocol != htons(ETH_P_MAP)) 100 goto err_drop_skb; 101 102 ret = ipa_endpoint_skb_tx(endpoint, skb); 103 if (ret) { 104 if (ret != -E2BIG) 105 return NETDEV_TX_BUSY; 106 goto err_drop_skb; 107 } 108 109 stats->tx_packets++; 110 stats->tx_bytes += skb_len; 111 112 return NETDEV_TX_OK; 113 114 err_drop_skb: 115 dev_kfree_skb_any(skb); 116 stats->tx_dropped++; 117 118 return NETDEV_TX_OK; 119 } 120 121 void ipa_modem_skb_rx(struct net_device *netdev, struct sk_buff *skb) 122 { 123 struct net_device_stats *stats = &netdev->stats; 124 125 if (skb) { 126 skb->dev = netdev; 127 skb->protocol = htons(ETH_P_MAP); 128 stats->rx_packets++; 129 stats->rx_bytes += skb->len; 130 131 (void)netif_receive_skb(skb); 132 } else { 133 stats->rx_dropped++; 134 } 135 } 136 137 static const struct net_device_ops ipa_modem_ops = { 138 .ndo_open = ipa_open, 139 .ndo_stop = ipa_stop, 140 .ndo_start_xmit = ipa_start_xmit, 141 }; 142 143 /** ipa_modem_netdev_setup() - netdev setup function for the modem */ 144 static void ipa_modem_netdev_setup(struct net_device *netdev) 145 { 146 netdev->netdev_ops = &ipa_modem_ops; 147 ether_setup(netdev); 148 /* No header ops (override value set by ether_setup()) */ 149 netdev->header_ops = NULL; 150 netdev->type = ARPHRD_RAWIP; 151 netdev->hard_header_len = 0; 152 netdev->max_mtu = IPA_MTU; 153 netdev->mtu = netdev->max_mtu; 154 netdev->addr_len = 0; 155 netdev->flags &= ~(IFF_BROADCAST | IFF_MULTICAST); 156 /* The endpoint is configured for QMAP */ 157 netdev->needed_headroom = sizeof(struct rmnet_map_header); 158 netdev->needed_tailroom = IPA_NETDEV_TAILROOM; 159 netdev->watchdog_timeo = IPA_NETDEV_TIMEOUT * HZ; 160 netdev->hw_features = NETIF_F_SG; 161 } 162 163 /** ipa_modem_suspend() - suspend callback 164 * @netdev: Network device 165 * 166 * Suspend the modem's endpoints. 167 */ 168 void ipa_modem_suspend(struct net_device *netdev) 169 { 170 struct ipa_priv *priv = netdev_priv(netdev); 171 struct ipa *ipa = priv->ipa; 172 173 netif_stop_queue(netdev); 174 175 ipa_endpoint_suspend_one(ipa->name_map[IPA_ENDPOINT_AP_MODEM_RX]); 176 ipa_endpoint_suspend_one(ipa->name_map[IPA_ENDPOINT_AP_MODEM_TX]); 177 } 178 179 /** ipa_modem_resume() - resume callback for runtime_pm 180 * @dev: pointer to device 181 * 182 * Resume the modem's endpoints. 183 */ 184 void ipa_modem_resume(struct net_device *netdev) 185 { 186 struct ipa_priv *priv = netdev_priv(netdev); 187 struct ipa *ipa = priv->ipa; 188 189 ipa_endpoint_resume_one(ipa->name_map[IPA_ENDPOINT_AP_MODEM_TX]); 190 ipa_endpoint_resume_one(ipa->name_map[IPA_ENDPOINT_AP_MODEM_RX]); 191 192 netif_wake_queue(netdev); 193 } 194 195 int ipa_modem_start(struct ipa *ipa) 196 { 197 enum ipa_modem_state state; 198 struct net_device *netdev; 199 struct ipa_priv *priv; 200 int ret; 201 202 /* Only attempt to start the modem if it's stopped */ 203 state = atomic_cmpxchg(&ipa->modem_state, IPA_MODEM_STATE_STOPPED, 204 IPA_MODEM_STATE_STARTING); 205 206 /* Silently ignore attempts when running, or when changing state */ 207 if (state != IPA_MODEM_STATE_STOPPED) 208 return 0; 209 210 netdev = alloc_netdev(sizeof(struct ipa_priv), IPA_NETDEV_NAME, 211 NET_NAME_UNKNOWN, ipa_modem_netdev_setup); 212 if (!netdev) { 213 ret = -ENOMEM; 214 goto out_set_state; 215 } 216 217 SET_NETDEV_DEV(netdev, &ipa->pdev->dev); 218 priv = netdev_priv(netdev); 219 priv->ipa = ipa; 220 221 ret = register_netdev(netdev); 222 if (!ret) { 223 ipa->modem_netdev = netdev; 224 ipa->name_map[IPA_ENDPOINT_AP_MODEM_TX]->netdev = netdev; 225 ipa->name_map[IPA_ENDPOINT_AP_MODEM_RX]->netdev = netdev; 226 } else { 227 free_netdev(netdev); 228 } 229 230 out_set_state: 231 if (ret) 232 atomic_set(&ipa->modem_state, IPA_MODEM_STATE_STOPPED); 233 else 234 atomic_set(&ipa->modem_state, IPA_MODEM_STATE_RUNNING); 235 smp_mb__after_atomic(); 236 237 return ret; 238 } 239 240 int ipa_modem_stop(struct ipa *ipa) 241 { 242 struct net_device *netdev = ipa->modem_netdev; 243 enum ipa_modem_state state; 244 245 /* Only attempt to stop the modem if it's running */ 246 state = atomic_cmpxchg(&ipa->modem_state, IPA_MODEM_STATE_RUNNING, 247 IPA_MODEM_STATE_STOPPING); 248 249 /* Silently ignore attempts when already stopped */ 250 if (state == IPA_MODEM_STATE_STOPPED) 251 return 0; 252 253 /* If we're somewhere between stopped and starting, we're busy */ 254 if (state != IPA_MODEM_STATE_RUNNING) 255 return -EBUSY; 256 257 /* Prevent the modem from triggering a call to ipa_setup() */ 258 ipa_smp2p_disable(ipa); 259 260 /* Stop the queue and disable the endpoints if it's open */ 261 if (netdev) { 262 (void)ipa_stop(netdev); 263 ipa->name_map[IPA_ENDPOINT_AP_MODEM_RX]->netdev = NULL; 264 ipa->name_map[IPA_ENDPOINT_AP_MODEM_TX]->netdev = NULL; 265 ipa->modem_netdev = NULL; 266 unregister_netdev(netdev); 267 free_netdev(netdev); 268 } 269 270 atomic_set(&ipa->modem_state, IPA_MODEM_STATE_STOPPED); 271 smp_mb__after_atomic(); 272 273 return 0; 274 } 275 276 /* Treat a "clean" modem stop the same as a crash */ 277 static void ipa_modem_crashed(struct ipa *ipa) 278 { 279 struct device *dev = &ipa->pdev->dev; 280 int ret; 281 282 ipa_endpoint_modem_pause_all(ipa, true); 283 284 ipa_endpoint_modem_hol_block_clear_all(ipa); 285 286 ipa_table_reset(ipa, true); 287 288 ret = ipa_table_hash_flush(ipa); 289 if (ret) 290 dev_err(dev, "error %d flushing hash caches\n", ret); 291 292 ret = ipa_endpoint_modem_exception_reset_all(ipa); 293 if (ret) 294 dev_err(dev, "error %d resetting exception endpoint\n", ret); 295 296 ipa_endpoint_modem_pause_all(ipa, false); 297 298 ret = ipa_modem_stop(ipa); 299 if (ret) 300 dev_err(dev, "error %d stopping modem\n", ret); 301 302 /* Now prepare for the next modem boot */ 303 ret = ipa_mem_zero_modem(ipa); 304 if (ret) 305 dev_err(dev, "error %d zeroing modem memory regions\n", ret); 306 } 307 308 static int ipa_modem_notify(struct notifier_block *nb, unsigned long action, 309 void *data) 310 { 311 struct ipa *ipa = container_of(nb, struct ipa, nb); 312 struct qcom_ssr_notify_data *notify_data = data; 313 struct device *dev = &ipa->pdev->dev; 314 315 switch (action) { 316 case QCOM_SSR_BEFORE_POWERUP: 317 dev_info(dev, "received modem starting event\n"); 318 ipa_uc_clock(ipa); 319 ipa_smp2p_notify_reset(ipa); 320 break; 321 322 case QCOM_SSR_AFTER_POWERUP: 323 dev_info(dev, "received modem running event\n"); 324 break; 325 326 case QCOM_SSR_BEFORE_SHUTDOWN: 327 dev_info(dev, "received modem %s event\n", 328 notify_data->crashed ? "crashed" : "stopping"); 329 if (ipa->setup_complete) 330 ipa_modem_crashed(ipa); 331 break; 332 333 case QCOM_SSR_AFTER_SHUTDOWN: 334 dev_info(dev, "received modem offline event\n"); 335 break; 336 337 default: 338 dev_err(dev, "received unrecognized event %lu\n", action); 339 break; 340 } 341 342 return NOTIFY_OK; 343 } 344 345 int ipa_modem_init(struct ipa *ipa, bool modem_init) 346 { 347 return ipa_smp2p_init(ipa, modem_init); 348 } 349 350 void ipa_modem_exit(struct ipa *ipa) 351 { 352 ipa_smp2p_exit(ipa); 353 } 354 355 int ipa_modem_config(struct ipa *ipa) 356 { 357 void *notifier; 358 359 ipa->nb.notifier_call = ipa_modem_notify; 360 361 notifier = qcom_register_ssr_notifier("mpss", &ipa->nb); 362 if (IS_ERR(notifier)) 363 return PTR_ERR(notifier); 364 365 ipa->notifier = notifier; 366 367 return 0; 368 } 369 370 void ipa_modem_deconfig(struct ipa *ipa) 371 { 372 struct device *dev = &ipa->pdev->dev; 373 int ret; 374 375 ret = qcom_unregister_ssr_notifier(ipa->notifier, &ipa->nb); 376 if (ret) 377 dev_err(dev, "error %d unregistering notifier", ret); 378 379 ipa->notifier = NULL; 380 memset(&ipa->nb, 0, sizeof(ipa->nb)); 381 } 382