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  *  Amir Hanania <amir.hanania@intel.com>
8  *  Haijun Liu <haijun.liu@mediatek.com>
9  *  Moises Veleta <moises.veleta@intel.com>
10  *  Ricardo Martinez <ricardo.martinez@linux.intel.com>
11  *
12  * Contributors:
13  *  Andy Shevchenko <andriy.shevchenko@linux.intel.com>
14  *  Chandrashekar Devegowda <chandrashekar.devegowda@intel.com>
15  *  Chiranjeevi Rapolu <chiranjeevi.rapolu@intel.com>
16  *  Eliot Lee <eliot.lee@intel.com>
17  *  Sreehari Kancharla <sreehari.kancharla@intel.com>
18  */
19 
20 #include <linux/bits.h>
21 #include <linux/bitfield.h>
22 #include <linux/device.h>
23 #include <linux/gfp.h>
24 #include <linux/kernel.h>
25 #include <linux/kthread.h>
26 #include <linux/list.h>
27 #include <linux/mutex.h>
28 #include <linux/netdevice.h>
29 #include <linux/skbuff.h>
30 #include <linux/spinlock.h>
31 #include <linux/wait.h>
32 #include <linux/wwan.h>
33 
34 #include "t7xx_hif_cldma.h"
35 #include "t7xx_modem_ops.h"
36 #include "t7xx_port.h"
37 #include "t7xx_port_proxy.h"
38 #include "t7xx_state_monitor.h"
39 
40 #define Q_IDX_CTRL			0
41 #define Q_IDX_MBIM			2
42 #define Q_IDX_AT_CMD			5
43 
44 #define INVALID_SEQ_NUM			GENMASK(15, 0)
45 
46 #define for_each_proxy_port(i, p, proxy)	\
47 	for (i = 0, (p) = &(proxy)->ports[i];	\
48 	     i < (proxy)->port_count;		\
49 	     i++, (p) = &(proxy)->ports[i])
50 
51 static const struct t7xx_port_conf t7xx_md_port_conf[] = {
52 	{
53 		.tx_ch = PORT_CH_UART2_TX,
54 		.rx_ch = PORT_CH_UART2_RX,
55 		.txq_index = Q_IDX_AT_CMD,
56 		.rxq_index = Q_IDX_AT_CMD,
57 		.txq_exp_index = 0xff,
58 		.rxq_exp_index = 0xff,
59 		.path_id = CLDMA_ID_MD,
60 		.ops = &wwan_sub_port_ops,
61 		.name = "AT",
62 		.port_type = WWAN_PORT_AT,
63 	}, {
64 		.tx_ch = PORT_CH_MBIM_TX,
65 		.rx_ch = PORT_CH_MBIM_RX,
66 		.txq_index = Q_IDX_MBIM,
67 		.rxq_index = Q_IDX_MBIM,
68 		.path_id = CLDMA_ID_MD,
69 		.ops = &wwan_sub_port_ops,
70 		.name = "MBIM",
71 		.port_type = WWAN_PORT_MBIM,
72 	}, {
73 		.tx_ch = PORT_CH_CONTROL_TX,
74 		.rx_ch = PORT_CH_CONTROL_RX,
75 		.txq_index = Q_IDX_CTRL,
76 		.rxq_index = Q_IDX_CTRL,
77 		.path_id = CLDMA_ID_MD,
78 		.ops = &ctl_port_ops,
79 		.name = "t7xx_ctrl",
80 	},
81 };
82 
83 static struct t7xx_port *t7xx_proxy_get_port_by_ch(struct port_proxy *port_prox, enum port_ch ch)
84 {
85 	const struct t7xx_port_conf *port_conf;
86 	struct t7xx_port *port;
87 	int i;
88 
89 	for_each_proxy_port(i, port, port_prox) {
90 		port_conf = port->port_conf;
91 		if (port_conf->rx_ch == ch || port_conf->tx_ch == ch)
92 			return port;
93 	}
94 
95 	return NULL;
96 }
97 
98 static u16 t7xx_port_next_rx_seq_num(struct t7xx_port *port, struct ccci_header *ccci_h)
99 {
100 	u32 status = le32_to_cpu(ccci_h->status);
101 	u16 seq_num, next_seq_num;
102 	bool assert_bit;
103 
104 	seq_num = FIELD_GET(CCCI_H_SEQ_FLD, status);
105 	next_seq_num = (seq_num + 1) & FIELD_MAX(CCCI_H_SEQ_FLD);
106 	assert_bit = status & CCCI_H_AST_BIT;
107 	if (!assert_bit || port->seq_nums[MTK_RX] == INVALID_SEQ_NUM)
108 		return next_seq_num;
109 
110 	if (seq_num != port->seq_nums[MTK_RX])
111 		dev_warn_ratelimited(port->dev,
112 				     "seq num out-of-order %u != %u (header %X, len %X)\n",
113 				     seq_num, port->seq_nums[MTK_RX],
114 				     le32_to_cpu(ccci_h->packet_header),
115 				     le32_to_cpu(ccci_h->packet_len));
116 
117 	return next_seq_num;
118 }
119 
120 void t7xx_port_proxy_reset(struct port_proxy *port_prox)
121 {
122 	struct t7xx_port *port;
123 	int i;
124 
125 	for_each_proxy_port(i, port, port_prox) {
126 		port->seq_nums[MTK_RX] = INVALID_SEQ_NUM;
127 		port->seq_nums[MTK_TX] = 0;
128 	}
129 }
130 
131 static int t7xx_port_get_queue_no(struct t7xx_port *port)
132 {
133 	const struct t7xx_port_conf *port_conf = port->port_conf;
134 	struct t7xx_fsm_ctl *ctl = port->t7xx_dev->md->fsm_ctl;
135 
136 	return t7xx_fsm_get_md_state(ctl) == MD_STATE_EXCEPTION ?
137 		port_conf->txq_exp_index : port_conf->txq_index;
138 }
139 
140 static void t7xx_port_struct_init(struct t7xx_port *port)
141 {
142 	INIT_LIST_HEAD(&port->entry);
143 	INIT_LIST_HEAD(&port->queue_entry);
144 	skb_queue_head_init(&port->rx_skb_list);
145 	init_waitqueue_head(&port->rx_wq);
146 	port->seq_nums[MTK_RX] = INVALID_SEQ_NUM;
147 	port->seq_nums[MTK_TX] = 0;
148 	atomic_set(&port->usage_cnt, 0);
149 }
150 
151 struct sk_buff *t7xx_port_alloc_skb(int payload)
152 {
153 	struct sk_buff *skb = __dev_alloc_skb(payload + sizeof(struct ccci_header), GFP_KERNEL);
154 
155 	if (skb)
156 		skb_reserve(skb, sizeof(struct ccci_header));
157 
158 	return skb;
159 }
160 
161 struct sk_buff *t7xx_ctrl_alloc_skb(int payload)
162 {
163 	struct sk_buff *skb = t7xx_port_alloc_skb(payload + sizeof(struct ctrl_msg_header));
164 
165 	if (skb)
166 		skb_reserve(skb, sizeof(struct ctrl_msg_header));
167 
168 	return skb;
169 }
170 
171 /**
172  * t7xx_port_enqueue_skb() - Enqueue the received skb into the port's rx_skb_list.
173  * @port: port context.
174  * @skb: received skb.
175  *
176  * Return:
177  * * 0		- Success.
178  * * -ENOBUFS	- Not enough buffer space. Caller will try again later, skb is not consumed.
179  */
180 int t7xx_port_enqueue_skb(struct t7xx_port *port, struct sk_buff *skb)
181 {
182 	unsigned long flags;
183 
184 	spin_lock_irqsave(&port->rx_wq.lock, flags);
185 	if (port->rx_skb_list.qlen >= port->rx_length_th) {
186 		spin_unlock_irqrestore(&port->rx_wq.lock, flags);
187 
188 		return -ENOBUFS;
189 	}
190 	__skb_queue_tail(&port->rx_skb_list, skb);
191 	spin_unlock_irqrestore(&port->rx_wq.lock, flags);
192 
193 	wake_up_all(&port->rx_wq);
194 	return 0;
195 }
196 
197 static int t7xx_port_send_raw_skb(struct t7xx_port *port, struct sk_buff *skb)
198 {
199 	enum cldma_id path_id = port->port_conf->path_id;
200 	struct cldma_ctrl *md_ctrl;
201 	int ret, tx_qno;
202 
203 	md_ctrl = port->t7xx_dev->md->md_ctrl[path_id];
204 	tx_qno = t7xx_port_get_queue_no(port);
205 	ret = t7xx_cldma_send_skb(md_ctrl, tx_qno, skb);
206 	if (ret)
207 		dev_err(port->dev, "Failed to send skb: %d\n", ret);
208 
209 	return ret;
210 }
211 
212 static int t7xx_port_send_ccci_skb(struct t7xx_port *port, struct sk_buff *skb,
213 				   unsigned int pkt_header, unsigned int ex_msg)
214 {
215 	const struct t7xx_port_conf *port_conf = port->port_conf;
216 	struct ccci_header *ccci_h;
217 	u32 status;
218 	int ret;
219 
220 	ccci_h = skb_push(skb, sizeof(*ccci_h));
221 	status = FIELD_PREP(CCCI_H_CHN_FLD, port_conf->tx_ch) |
222 		 FIELD_PREP(CCCI_H_SEQ_FLD, port->seq_nums[MTK_TX]) | CCCI_H_AST_BIT;
223 	ccci_h->status = cpu_to_le32(status);
224 	ccci_h->packet_header = cpu_to_le32(pkt_header);
225 	ccci_h->packet_len = cpu_to_le32(skb->len);
226 	ccci_h->ex_msg = cpu_to_le32(ex_msg);
227 
228 	ret = t7xx_port_send_raw_skb(port, skb);
229 	if (ret)
230 		return ret;
231 
232 	port->seq_nums[MTK_TX]++;
233 	return 0;
234 }
235 
236 int t7xx_port_send_ctl_skb(struct t7xx_port *port, struct sk_buff *skb, unsigned int msg,
237 			   unsigned int ex_msg)
238 {
239 	struct ctrl_msg_header *ctrl_msg_h;
240 	unsigned int msg_len = skb->len;
241 	u32 pkt_header = 0;
242 
243 	ctrl_msg_h = skb_push(skb, sizeof(*ctrl_msg_h));
244 	ctrl_msg_h->ctrl_msg_id = cpu_to_le32(msg);
245 	ctrl_msg_h->ex_msg = cpu_to_le32(ex_msg);
246 	ctrl_msg_h->data_length = cpu_to_le32(msg_len);
247 
248 	if (!msg_len)
249 		pkt_header = CCCI_HEADER_NO_DATA;
250 
251 	return t7xx_port_send_ccci_skb(port, skb, pkt_header, ex_msg);
252 }
253 
254 int t7xx_port_send_skb(struct t7xx_port *port, struct sk_buff *skb, unsigned int pkt_header,
255 		       unsigned int ex_msg)
256 {
257 	struct t7xx_fsm_ctl *ctl = port->t7xx_dev->md->fsm_ctl;
258 	unsigned int fsm_state;
259 
260 	fsm_state = t7xx_fsm_get_ctl_state(ctl);
261 	if (fsm_state != FSM_STATE_PRE_START) {
262 		const struct t7xx_port_conf *port_conf = port->port_conf;
263 		enum md_state md_state = t7xx_fsm_get_md_state(ctl);
264 
265 		switch (md_state) {
266 		case MD_STATE_EXCEPTION:
267 			if (port_conf->tx_ch != PORT_CH_MD_LOG_TX)
268 				return -EBUSY;
269 			break;
270 
271 		case MD_STATE_WAITING_FOR_HS1:
272 		case MD_STATE_WAITING_FOR_HS2:
273 		case MD_STATE_STOPPED:
274 		case MD_STATE_WAITING_TO_STOP:
275 		case MD_STATE_INVALID:
276 			return -ENODEV;
277 
278 		default:
279 			break;
280 		}
281 	}
282 
283 	return t7xx_port_send_ccci_skb(port, skb, pkt_header, ex_msg);
284 }
285 
286 static void t7xx_proxy_setup_ch_mapping(struct port_proxy *port_prox)
287 {
288 	struct t7xx_port *port;
289 
290 	int i, j;
291 
292 	for (i = 0; i < ARRAY_SIZE(port_prox->rx_ch_ports); i++)
293 		INIT_LIST_HEAD(&port_prox->rx_ch_ports[i]);
294 
295 	for (j = 0; j < ARRAY_SIZE(port_prox->queue_ports); j++) {
296 		for (i = 0; i < ARRAY_SIZE(port_prox->queue_ports[j]); i++)
297 			INIT_LIST_HEAD(&port_prox->queue_ports[j][i]);
298 	}
299 
300 	for_each_proxy_port(i, port, port_prox) {
301 		const struct t7xx_port_conf *port_conf = port->port_conf;
302 		enum cldma_id path_id = port_conf->path_id;
303 		u8 ch_id;
304 
305 		ch_id = FIELD_GET(PORT_CH_ID_MASK, port_conf->rx_ch);
306 		list_add_tail(&port->entry, &port_prox->rx_ch_ports[ch_id]);
307 		list_add_tail(&port->queue_entry,
308 			      &port_prox->queue_ports[path_id][port_conf->rxq_index]);
309 	}
310 }
311 
312 static struct t7xx_port *t7xx_port_proxy_find_port(struct t7xx_pci_dev *t7xx_dev,
313 						   struct cldma_queue *queue, u16 channel)
314 {
315 	struct port_proxy *port_prox = t7xx_dev->md->port_prox;
316 	struct list_head *port_list;
317 	struct t7xx_port *port;
318 	u8 ch_id;
319 
320 	ch_id = FIELD_GET(PORT_CH_ID_MASK, channel);
321 	port_list = &port_prox->rx_ch_ports[ch_id];
322 	list_for_each_entry(port, port_list, entry) {
323 		const struct t7xx_port_conf *port_conf = port->port_conf;
324 
325 		if (queue->md_ctrl->hif_id == port_conf->path_id &&
326 		    channel == port_conf->rx_ch)
327 			return port;
328 	}
329 
330 	return NULL;
331 }
332 
333 /**
334  * t7xx_port_proxy_recv_skb() - Dispatch received skb.
335  * @queue: CLDMA queue.
336  * @skb: Socket buffer.
337  *
338  * Return:
339  ** 0		- Packet consumed.
340  ** -ERROR	- Failed to process skb.
341  */
342 static int t7xx_port_proxy_recv_skb(struct cldma_queue *queue, struct sk_buff *skb)
343 {
344 	struct ccci_header *ccci_h = (struct ccci_header *)skb->data;
345 	struct t7xx_pci_dev *t7xx_dev = queue->md_ctrl->t7xx_dev;
346 	struct t7xx_fsm_ctl *ctl = t7xx_dev->md->fsm_ctl;
347 	struct device *dev = queue->md_ctrl->dev;
348 	const struct t7xx_port_conf *port_conf;
349 	struct t7xx_port *port;
350 	u16 seq_num, channel;
351 	int ret;
352 
353 	channel = FIELD_GET(CCCI_H_CHN_FLD, le32_to_cpu(ccci_h->status));
354 	if (t7xx_fsm_get_md_state(ctl) == MD_STATE_INVALID) {
355 		dev_err_ratelimited(dev, "Packet drop on channel 0x%x, modem not ready\n", channel);
356 		goto drop_skb;
357 	}
358 
359 	port = t7xx_port_proxy_find_port(t7xx_dev, queue, channel);
360 	if (!port) {
361 		dev_err_ratelimited(dev, "Packet drop on channel 0x%x, port not found\n", channel);
362 		goto drop_skb;
363 	}
364 
365 	seq_num = t7xx_port_next_rx_seq_num(port, ccci_h);
366 	port_conf = port->port_conf;
367 	skb_pull(skb, sizeof(*ccci_h));
368 
369 	ret = port_conf->ops->recv_skb(port, skb);
370 	/* Error indicates to try again later */
371 	if (ret) {
372 		skb_push(skb, sizeof(*ccci_h));
373 		return ret;
374 	}
375 
376 	port->seq_nums[MTK_RX] = seq_num;
377 	return 0;
378 
379 drop_skb:
380 	dev_kfree_skb_any(skb);
381 	return 0;
382 }
383 
384 /**
385  * t7xx_port_proxy_md_status_notify() - Notify all ports of state.
386  *@port_prox: The port_proxy pointer.
387  *@state: State.
388  *
389  * Called by t7xx_fsm. Used to dispatch modem status for all ports,
390  * which want to know MD state transition.
391  */
392 void t7xx_port_proxy_md_status_notify(struct port_proxy *port_prox, unsigned int state)
393 {
394 	struct t7xx_port *port;
395 	int i;
396 
397 	for_each_proxy_port(i, port, port_prox) {
398 		const struct t7xx_port_conf *port_conf = port->port_conf;
399 
400 		if (port_conf->ops->md_state_notify)
401 			port_conf->ops->md_state_notify(port, state);
402 	}
403 }
404 
405 static void t7xx_proxy_init_all_ports(struct t7xx_modem *md)
406 {
407 	struct port_proxy *port_prox = md->port_prox;
408 	struct t7xx_port *port;
409 	int i;
410 
411 	for_each_proxy_port(i, port, port_prox) {
412 		const struct t7xx_port_conf *port_conf = port->port_conf;
413 
414 		t7xx_port_struct_init(port);
415 
416 		if (port_conf->tx_ch == PORT_CH_CONTROL_TX)
417 			md->core_md.ctl_port = port;
418 
419 		port->t7xx_dev = md->t7xx_dev;
420 		port->dev = &md->t7xx_dev->pdev->dev;
421 		spin_lock_init(&port->port_update_lock);
422 		port->chan_enable = false;
423 
424 		if (port_conf->ops->init)
425 			port_conf->ops->init(port);
426 	}
427 
428 	t7xx_proxy_setup_ch_mapping(port_prox);
429 }
430 
431 static int t7xx_proxy_alloc(struct t7xx_modem *md)
432 {
433 	unsigned int port_count = ARRAY_SIZE(t7xx_md_port_conf);
434 	struct device *dev = &md->t7xx_dev->pdev->dev;
435 	struct port_proxy *port_prox;
436 	int i;
437 
438 	port_prox = devm_kzalloc(dev, sizeof(*port_prox) + sizeof(struct t7xx_port) * port_count,
439 				 GFP_KERNEL);
440 	if (!port_prox)
441 		return -ENOMEM;
442 
443 	md->port_prox = port_prox;
444 	port_prox->dev = dev;
445 
446 	for (i = 0; i < port_count; i++)
447 		port_prox->ports[i].port_conf = &t7xx_md_port_conf[i];
448 
449 	port_prox->port_count = port_count;
450 	t7xx_proxy_init_all_ports(md);
451 	return 0;
452 }
453 
454 /**
455  * t7xx_port_proxy_init() - Initialize ports.
456  * @md: Modem.
457  *
458  * Create all port instances.
459  *
460  * Return:
461  * * 0		- Success.
462  * * -ERROR	- Error code from failure sub-initializations.
463  */
464 int t7xx_port_proxy_init(struct t7xx_modem *md)
465 {
466 	int ret;
467 
468 	ret = t7xx_proxy_alloc(md);
469 	if (ret)
470 		return ret;
471 
472 	t7xx_cldma_set_recv_skb(md->md_ctrl[CLDMA_ID_MD], t7xx_port_proxy_recv_skb);
473 	return 0;
474 }
475 
476 void t7xx_port_proxy_uninit(struct port_proxy *port_prox)
477 {
478 	struct t7xx_port *port;
479 	int i;
480 
481 	for_each_proxy_port(i, port, port_prox) {
482 		const struct t7xx_port_conf *port_conf = port->port_conf;
483 
484 		if (port_conf->ops->uninit)
485 			port_conf->ops->uninit(port);
486 	}
487 }
488 
489 int t7xx_port_proxy_chl_enable_disable(struct port_proxy *port_prox, unsigned int ch_id,
490 				       bool en_flag)
491 {
492 	struct t7xx_port *port = t7xx_proxy_get_port_by_ch(port_prox, ch_id);
493 	const struct t7xx_port_conf *port_conf;
494 
495 	if (!port)
496 		return -EINVAL;
497 
498 	port_conf = port->port_conf;
499 
500 	if (en_flag) {
501 		if (port_conf->ops->enable_chl)
502 			port_conf->ops->enable_chl(port);
503 	} else {
504 		if (port_conf->ops->disable_chl)
505 			port_conf->ops->disable_chl(port);
506 	}
507 
508 	return 0;
509 }
510