1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2021, MediaTek Inc.
4 * Copyright (c) 2021-2022, Intel Corporation.
5 *
6 * Authors:
7 * Chandrashekar Devegowda <chandrashekar.devegowda@intel.com>
8 * Haijun Liu <haijun.liu@mediatek.com>
9 * Ricardo Martinez <ricardo.martinez@linux.intel.com>
10 *
11 * Contributors:
12 * Amir Hanania <amir.hanania@intel.com>
13 * Andy Shevchenko <andriy.shevchenko@linux.intel.com>
14 * Chiranjeevi Rapolu <chiranjeevi.rapolu@intel.com>
15 * Eliot Lee <eliot.lee@intel.com>
16 * Moises Veleta <moises.veleta@intel.com>
17 * Sreehari Kancharla <sreehari.kancharla@intel.com>
18 */
19
20#include <linux/atomic.h>
21#include <linux/device.h>
22#include <linux/gfp.h>
23#include <linux/if_arp.h>
24#include <linux/if_ether.h>
25#include <linux/ip.h>
26#include <linux/kernel.h>
27#include <linux/list.h>
28#include <linux/netdev_features.h>
29#include <linux/netdevice.h>
30#include <linux/pm_runtime.h>
31#include <linux/skbuff.h>
32#include <linux/types.h>
33#include <linux/wwan.h>
34#include <net/ipv6.h>
35#include <net/pkt_sched.h>
36
37#include "t7xx_hif_dpmaif_rx.h"
38#include "t7xx_hif_dpmaif_tx.h"
39#include "t7xx_netdev.h"
40#include "t7xx_pci.h"
41#include "t7xx_port_proxy.h"
42#include "t7xx_state_monitor.h"
43
44#define IP_MUX_SESSION_DEFAULT 0
45#define SBD_PACKET_TYPE_MASK GENMASK(7, 4)
46
47static void t7xx_ccmni_enable_napi(struct t7xx_ccmni_ctrl *ctlb)
48{
49 struct dpmaif_ctrl *ctrl;
50 int i, ret;
51
52 ctrl = ctlb->hif_ctrl;
53
54 if (ctlb->is_napi_en)
55 return;
56
57 for (i = 0; i < RXQ_NUM; i++) {
58 /* The usage count has to be bumped every time before calling
59 * napi_schedule. It will be decresed in the poll routine,
60 * right after napi_complete_done is called.
61 */
62 ret = pm_runtime_resume_and_get(dev: ctrl->dev);
63 if (ret < 0) {
64 dev_err(ctrl->dev, "Failed to resume device: %d\n",
65 ret);
66 return;
67 }
68 napi_enable(n: ctlb->napi[i]);
69 napi_schedule(n: ctlb->napi[i]);
70 }
71 ctlb->is_napi_en = true;
72}
73
74static void t7xx_ccmni_disable_napi(struct t7xx_ccmni_ctrl *ctlb)
75{
76 int i;
77
78 if (!ctlb->is_napi_en)
79 return;
80
81 for (i = 0; i < RXQ_NUM; i++) {
82 napi_synchronize(n: ctlb->napi[i]);
83 napi_disable(n: ctlb->napi[i]);
84 }
85
86 ctlb->is_napi_en = false;
87}
88
89static int t7xx_ccmni_open(struct net_device *dev)
90{
91 struct t7xx_ccmni *ccmni = wwan_netdev_drvpriv(dev);
92 struct t7xx_ccmni_ctrl *ccmni_ctl = ccmni->ctlb;
93
94 netif_carrier_on(dev);
95 netif_tx_start_all_queues(dev);
96 if (!atomic_fetch_inc(v: &ccmni_ctl->napi_usr_refcnt))
97 t7xx_ccmni_enable_napi(ctlb: ccmni_ctl);
98
99 atomic_inc(v: &ccmni->usage);
100 return 0;
101}
102
103static int t7xx_ccmni_close(struct net_device *dev)
104{
105 struct t7xx_ccmni *ccmni = wwan_netdev_drvpriv(dev);
106 struct t7xx_ccmni_ctrl *ccmni_ctl = ccmni->ctlb;
107
108 atomic_dec(v: &ccmni->usage);
109 if (atomic_dec_and_test(v: &ccmni_ctl->napi_usr_refcnt))
110 t7xx_ccmni_disable_napi(ctlb: ccmni_ctl);
111
112 netif_carrier_off(dev);
113 netif_tx_disable(dev);
114 return 0;
115}
116
117static int t7xx_ccmni_send_packet(struct t7xx_ccmni *ccmni, struct sk_buff *skb,
118 unsigned int txq_number)
119{
120 struct t7xx_ccmni_ctrl *ctlb = ccmni->ctlb;
121 struct t7xx_skb_cb *skb_cb = T7XX_SKB_CB(skb);
122
123 skb_cb->netif_idx = ccmni->index;
124
125 if (t7xx_dpmaif_tx_send_skb(dpmaif_ctrl: ctlb->hif_ctrl, txq_number, skb))
126 return NETDEV_TX_BUSY;
127
128 return 0;
129}
130
131static netdev_tx_t t7xx_ccmni_start_xmit(struct sk_buff *skb, struct net_device *dev)
132{
133 struct t7xx_ccmni *ccmni = wwan_netdev_drvpriv(dev);
134 int skb_len = skb->len;
135
136 /* If MTU is changed or there is no headroom, drop the packet */
137 if (skb->len > dev->mtu || skb_headroom(skb) < sizeof(struct ccci_header)) {
138 dev_kfree_skb(skb);
139 dev->stats.tx_dropped++;
140 return NETDEV_TX_OK;
141 }
142
143 if (t7xx_ccmni_send_packet(ccmni, skb, DPMAIF_TX_DEFAULT_QUEUE))
144 return NETDEV_TX_BUSY;
145
146 dev->stats.tx_packets++;
147 dev->stats.tx_bytes += skb_len;
148
149 return NETDEV_TX_OK;
150}
151
152static void t7xx_ccmni_tx_timeout(struct net_device *dev, unsigned int __always_unused txqueue)
153{
154 struct t7xx_ccmni *ccmni = netdev_priv(dev);
155
156 dev->stats.tx_errors++;
157
158 if (atomic_read(v: &ccmni->usage) > 0)
159 netif_tx_wake_all_queues(dev);
160}
161
162static const struct net_device_ops ccmni_netdev_ops = {
163 .ndo_open = t7xx_ccmni_open,
164 .ndo_stop = t7xx_ccmni_close,
165 .ndo_start_xmit = t7xx_ccmni_start_xmit,
166 .ndo_tx_timeout = t7xx_ccmni_tx_timeout,
167};
168
169static void t7xx_ccmni_start(struct t7xx_ccmni_ctrl *ctlb)
170{
171 struct t7xx_ccmni *ccmni;
172 int i;
173
174 for (i = 0; i < ctlb->nic_dev_num; i++) {
175 ccmni = ctlb->ccmni_inst[i];
176 if (!ccmni)
177 continue;
178
179 if (atomic_read(v: &ccmni->usage) > 0) {
180 netif_tx_start_all_queues(dev: ccmni->dev);
181 netif_carrier_on(dev: ccmni->dev);
182 }
183 }
184
185 if (atomic_read(v: &ctlb->napi_usr_refcnt))
186 t7xx_ccmni_enable_napi(ctlb);
187}
188
189static void t7xx_ccmni_pre_stop(struct t7xx_ccmni_ctrl *ctlb)
190{
191 struct t7xx_ccmni *ccmni;
192 int i;
193
194 for (i = 0; i < ctlb->nic_dev_num; i++) {
195 ccmni = ctlb->ccmni_inst[i];
196 if (!ccmni)
197 continue;
198
199 if (atomic_read(v: &ccmni->usage) > 0)
200 netif_tx_disable(dev: ccmni->dev);
201 }
202}
203
204static void t7xx_ccmni_post_stop(struct t7xx_ccmni_ctrl *ctlb)
205{
206 struct t7xx_ccmni *ccmni;
207 int i;
208
209 if (atomic_read(v: &ctlb->napi_usr_refcnt))
210 t7xx_ccmni_disable_napi(ctlb);
211
212 for (i = 0; i < ctlb->nic_dev_num; i++) {
213 ccmni = ctlb->ccmni_inst[i];
214 if (!ccmni)
215 continue;
216
217 if (atomic_read(v: &ccmni->usage) > 0)
218 netif_carrier_off(dev: ccmni->dev);
219 }
220}
221
222static void t7xx_ccmni_wwan_setup(struct net_device *dev)
223{
224 dev->needed_headroom += sizeof(struct ccci_header);
225
226 dev->mtu = ETH_DATA_LEN;
227 dev->max_mtu = CCMNI_MTU_MAX;
228 BUILD_BUG_ON(CCMNI_MTU_MAX > DPMAIF_HW_MTU_SIZE);
229
230 dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN;
231 dev->watchdog_timeo = CCMNI_NETDEV_WDT_TO;
232
233 dev->flags = IFF_POINTOPOINT | IFF_NOARP;
234
235 dev->features = NETIF_F_VLAN_CHALLENGED;
236
237 dev->features |= NETIF_F_SG;
238 dev->hw_features |= NETIF_F_SG;
239
240 dev->features |= NETIF_F_HW_CSUM;
241 dev->hw_features |= NETIF_F_HW_CSUM;
242
243 dev->features |= NETIF_F_RXCSUM;
244 dev->hw_features |= NETIF_F_RXCSUM;
245
246 dev->features |= NETIF_F_GRO;
247 dev->hw_features |= NETIF_F_GRO;
248
249 dev->needs_free_netdev = true;
250
251 dev->type = ARPHRD_NONE;
252
253 dev->netdev_ops = &ccmni_netdev_ops;
254}
255
256static void t7xx_init_netdev_napi(struct t7xx_ccmni_ctrl *ctlb)
257{
258 int i;
259
260 /* one HW, but shared with multiple net devices,
261 * so add a dummy device for NAPI.
262 */
263 init_dummy_netdev(dev: &ctlb->dummy_dev);
264 atomic_set(v: &ctlb->napi_usr_refcnt, i: 0);
265 ctlb->is_napi_en = false;
266
267 for (i = 0; i < RXQ_NUM; i++) {
268 ctlb->napi[i] = &ctlb->hif_ctrl->rxq[i].napi;
269 netif_napi_add_weight(dev: &ctlb->dummy_dev, napi: ctlb->napi[i], poll: t7xx_dpmaif_napi_rx_poll,
270 NIC_NAPI_POLL_BUDGET);
271 }
272}
273
274static void t7xx_uninit_netdev_napi(struct t7xx_ccmni_ctrl *ctlb)
275{
276 int i;
277
278 for (i = 0; i < RXQ_NUM; i++) {
279 netif_napi_del(napi: ctlb->napi[i]);
280 ctlb->napi[i] = NULL;
281 }
282}
283
284static int t7xx_ccmni_wwan_newlink(void *ctxt, struct net_device *dev, u32 if_id,
285 struct netlink_ext_ack *extack)
286{
287 struct t7xx_ccmni_ctrl *ctlb = ctxt;
288 struct t7xx_ccmni *ccmni;
289 int ret;
290
291 if (if_id >= ARRAY_SIZE(ctlb->ccmni_inst))
292 return -EINVAL;
293
294 ccmni = wwan_netdev_drvpriv(dev);
295 ccmni->index = if_id;
296 ccmni->ctlb = ctlb;
297 ccmni->dev = dev;
298 atomic_set(v: &ccmni->usage, i: 0);
299 ctlb->ccmni_inst[if_id] = ccmni;
300
301 ret = register_netdevice(dev);
302 if (ret)
303 return ret;
304
305 netif_device_attach(dev);
306 return 0;
307}
308
309static void t7xx_ccmni_wwan_dellink(void *ctxt, struct net_device *dev, struct list_head *head)
310{
311 struct t7xx_ccmni *ccmni = wwan_netdev_drvpriv(dev);
312 struct t7xx_ccmni_ctrl *ctlb = ctxt;
313 u8 if_id = ccmni->index;
314
315 if (if_id >= ARRAY_SIZE(ctlb->ccmni_inst))
316 return;
317
318 if (WARN_ON(ctlb->ccmni_inst[if_id] != ccmni))
319 return;
320
321 unregister_netdevice(dev);
322}
323
324static const struct wwan_ops ccmni_wwan_ops = {
325 .priv_size = sizeof(struct t7xx_ccmni),
326 .setup = t7xx_ccmni_wwan_setup,
327 .newlink = t7xx_ccmni_wwan_newlink,
328 .dellink = t7xx_ccmni_wwan_dellink,
329};
330
331static int t7xx_ccmni_register_wwan(struct t7xx_ccmni_ctrl *ctlb)
332{
333 struct device *dev = ctlb->hif_ctrl->dev;
334 int ret;
335
336 if (ctlb->wwan_is_registered)
337 return 0;
338
339 /* WWAN core will create a netdev for the default IP MUX channel */
340 ret = wwan_register_ops(parent: dev, ops: &ccmni_wwan_ops, ctxt: ctlb, IP_MUX_SESSION_DEFAULT);
341 if (ret < 0) {
342 dev_err(dev, "Unable to register WWAN ops, %d\n", ret);
343 return ret;
344 }
345
346 ctlb->wwan_is_registered = true;
347 return 0;
348}
349
350static int t7xx_ccmni_md_state_callback(enum md_state state, void *para)
351{
352 struct t7xx_ccmni_ctrl *ctlb = para;
353 struct device *dev;
354 int ret = 0;
355
356 dev = ctlb->hif_ctrl->dev;
357 ctlb->md_sta = state;
358
359 switch (state) {
360 case MD_STATE_READY:
361 ret = t7xx_ccmni_register_wwan(ctlb);
362 if (!ret)
363 t7xx_ccmni_start(ctlb);
364 break;
365
366 case MD_STATE_EXCEPTION:
367 case MD_STATE_STOPPED:
368 t7xx_ccmni_pre_stop(ctlb);
369
370 ret = t7xx_dpmaif_md_state_callback(dpmaif_ctrl: ctlb->hif_ctrl, state);
371 if (ret < 0)
372 dev_err(dev, "DPMAIF md state callback err, state=%d\n", state);
373
374 t7xx_ccmni_post_stop(ctlb);
375 break;
376
377 case MD_STATE_WAITING_FOR_HS1:
378 case MD_STATE_WAITING_TO_STOP:
379 ret = t7xx_dpmaif_md_state_callback(dpmaif_ctrl: ctlb->hif_ctrl, state);
380 if (ret < 0)
381 dev_err(dev, "DPMAIF md state callback err, state=%d\n", state);
382
383 break;
384
385 default:
386 break;
387 }
388
389 return ret;
390}
391
392static void init_md_status_notifier(struct t7xx_pci_dev *t7xx_dev)
393{
394 struct t7xx_ccmni_ctrl *ctlb = t7xx_dev->ccmni_ctlb;
395 struct t7xx_fsm_notifier *md_status_notifier;
396
397 md_status_notifier = &ctlb->md_status_notify;
398 INIT_LIST_HEAD(list: &md_status_notifier->entry);
399 md_status_notifier->notifier_fn = t7xx_ccmni_md_state_callback;
400 md_status_notifier->data = ctlb;
401
402 t7xx_fsm_notifier_register(md: t7xx_dev->md, notifier: md_status_notifier);
403}
404
405static void t7xx_ccmni_recv_skb(struct t7xx_ccmni_ctrl *ccmni_ctlb, struct sk_buff *skb,
406 struct napi_struct *napi)
407{
408 struct t7xx_skb_cb *skb_cb;
409 struct net_device *net_dev;
410 struct t7xx_ccmni *ccmni;
411 int pkt_type, skb_len;
412 u8 netif_id;
413
414 skb_cb = T7XX_SKB_CB(skb);
415 netif_id = skb_cb->netif_idx;
416 ccmni = ccmni_ctlb->ccmni_inst[netif_id];
417 if (!ccmni) {
418 dev_kfree_skb(skb);
419 return;
420 }
421
422 net_dev = ccmni->dev;
423 pkt_type = skb_cb->rx_pkt_type;
424 skb->dev = net_dev;
425 if (pkt_type == PKT_TYPE_IP6)
426 skb->protocol = htons(ETH_P_IPV6);
427 else
428 skb->protocol = htons(ETH_P_IP);
429
430 skb_len = skb->len;
431 napi_gro_receive(napi, skb);
432 net_dev->stats.rx_packets++;
433 net_dev->stats.rx_bytes += skb_len;
434}
435
436static void t7xx_ccmni_queue_tx_irq_notify(struct t7xx_ccmni_ctrl *ctlb, int qno)
437{
438 struct t7xx_ccmni *ccmni = ctlb->ccmni_inst[0];
439 struct netdev_queue *net_queue;
440
441 if (netif_running(dev: ccmni->dev) && atomic_read(v: &ccmni->usage) > 0) {
442 net_queue = netdev_get_tx_queue(dev: ccmni->dev, index: qno);
443 if (netif_tx_queue_stopped(dev_queue: net_queue))
444 netif_tx_wake_queue(dev_queue: net_queue);
445 }
446}
447
448static void t7xx_ccmni_queue_tx_full_notify(struct t7xx_ccmni_ctrl *ctlb, int qno)
449{
450 struct t7xx_ccmni *ccmni = ctlb->ccmni_inst[0];
451 struct netdev_queue *net_queue;
452
453 if (atomic_read(v: &ccmni->usage) > 0) {
454 netdev_err(dev: ccmni->dev, format: "TX queue %d is full\n", qno);
455 net_queue = netdev_get_tx_queue(dev: ccmni->dev, index: qno);
456 netif_tx_stop_queue(dev_queue: net_queue);
457 }
458}
459
460static void t7xx_ccmni_queue_state_notify(struct t7xx_pci_dev *t7xx_dev,
461 enum dpmaif_txq_state state, int qno)
462{
463 struct t7xx_ccmni_ctrl *ctlb = t7xx_dev->ccmni_ctlb;
464
465 if (ctlb->md_sta != MD_STATE_READY)
466 return;
467
468 if (!ctlb->ccmni_inst[0]) {
469 dev_warn(&t7xx_dev->pdev->dev, "No netdev registered yet\n");
470 return;
471 }
472
473 if (state == DMPAIF_TXQ_STATE_IRQ)
474 t7xx_ccmni_queue_tx_irq_notify(ctlb, qno);
475 else if (state == DMPAIF_TXQ_STATE_FULL)
476 t7xx_ccmni_queue_tx_full_notify(ctlb, qno);
477}
478
479int t7xx_ccmni_init(struct t7xx_pci_dev *t7xx_dev)
480{
481 struct device *dev = &t7xx_dev->pdev->dev;
482 struct t7xx_ccmni_ctrl *ctlb;
483
484 ctlb = devm_kzalloc(dev, size: sizeof(*ctlb), GFP_KERNEL);
485 if (!ctlb)
486 return -ENOMEM;
487
488 t7xx_dev->ccmni_ctlb = ctlb;
489 ctlb->t7xx_dev = t7xx_dev;
490 ctlb->callbacks.state_notify = t7xx_ccmni_queue_state_notify;
491 ctlb->callbacks.recv_skb = t7xx_ccmni_recv_skb;
492 ctlb->nic_dev_num = NIC_DEV_DEFAULT;
493
494 ctlb->hif_ctrl = t7xx_dpmaif_hif_init(t7xx_dev, callbacks: &ctlb->callbacks);
495 if (!ctlb->hif_ctrl)
496 return -ENOMEM;
497
498 t7xx_init_netdev_napi(ctlb);
499 init_md_status_notifier(t7xx_dev);
500 return 0;
501}
502
503void t7xx_ccmni_exit(struct t7xx_pci_dev *t7xx_dev)
504{
505 struct t7xx_ccmni_ctrl *ctlb = t7xx_dev->ccmni_ctlb;
506
507 t7xx_fsm_notifier_unregister(md: t7xx_dev->md, notifier: &ctlb->md_status_notify);
508
509 if (ctlb->wwan_is_registered) {
510 wwan_unregister_ops(parent: &t7xx_dev->pdev->dev);
511 ctlb->wwan_is_registered = false;
512 }
513
514 t7xx_uninit_netdev_napi(ctlb);
515 t7xx_dpmaif_hif_exit(dpmaif_ctrl: ctlb->hif_ctrl);
516}
517

source code of linux/drivers/net/wwan/t7xx/t7xx_netdev.c