xref: /linux/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c (revision 8274d40eafa37b570ad7be8b7fe5fe507509c153)
1 // SPDX-License-Identifier: GPL-2.0+
2 
3 #include <linux/bpf.h>
4 #include <linux/filter.h>
5 #include <net/page_pool/helpers.h>
6 
7 #include "lan966x_main.h"
8 
9 static int lan966x_fdma_channel_active(struct lan966x *lan966x)
10 {
11 	return lan_rd(lan966x, FDMA_CH_ACTIVE);
12 }
13 
14 static struct page *lan966x_fdma_rx_alloc_page(struct lan966x_rx *rx,
15 					       struct lan966x_db *db)
16 {
17 	struct page *page;
18 
19 	page = page_pool_dev_alloc_pages(rx->page_pool);
20 	if (unlikely(!page))
21 		return NULL;
22 
23 	db->dataptr = page_pool_get_dma_addr(page) + XDP_PACKET_HEADROOM;
24 
25 	return page;
26 }
27 
28 static void lan966x_fdma_rx_free_pages(struct lan966x_rx *rx)
29 {
30 	struct fdma *fdma = &rx->fdma;
31 	int i, j;
32 
33 	for (i = 0; i < fdma->n_dcbs; ++i) {
34 		for (j = 0; j < fdma->n_dbs; ++j)
35 			page_pool_put_full_page(rx->page_pool,
36 						rx->page[i][j], false);
37 	}
38 }
39 
40 static void lan966x_fdma_rx_free_page(struct lan966x_rx *rx)
41 {
42 	struct fdma *fdma = &rx->fdma;
43 	struct page *page;
44 
45 	page = rx->page[fdma->dcb_index][fdma->db_index];
46 	if (unlikely(!page))
47 		return;
48 
49 	page_pool_recycle_direct(rx->page_pool, page);
50 }
51 
52 static void lan966x_fdma_rx_add_dcb(struct lan966x_rx *rx,
53 				    struct lan966x_rx_dcb *dcb,
54 				    u64 nextptr)
55 {
56 	struct fdma *fdma = &rx->fdma;
57 	struct lan966x_db *db;
58 	int i;
59 
60 	for (i = 0; i < fdma->n_dbs; ++i) {
61 		db = &dcb->db[i];
62 		db->status = FDMA_DCB_STATUS_INTR;
63 	}
64 
65 	dcb->nextptr = FDMA_DCB_INVALID_DATA;
66 	dcb->info = FDMA_DCB_INFO_DATAL(PAGE_SIZE << rx->page_order);
67 
68 	rx->last_entry->nextptr = nextptr;
69 	rx->last_entry = dcb;
70 }
71 
72 static int lan966x_fdma_rx_alloc_page_pool(struct lan966x_rx *rx)
73 {
74 	struct lan966x *lan966x = rx->lan966x;
75 	struct page_pool_params pp_params = {
76 		.order = rx->page_order,
77 		.flags = PP_FLAG_DMA_MAP | PP_FLAG_DMA_SYNC_DEV,
78 		.pool_size = rx->fdma.n_dcbs,
79 		.nid = NUMA_NO_NODE,
80 		.dev = lan966x->dev,
81 		.dma_dir = DMA_FROM_DEVICE,
82 		.offset = XDP_PACKET_HEADROOM,
83 		.max_len = rx->max_mtu -
84 			   SKB_DATA_ALIGN(sizeof(struct skb_shared_info)),
85 	};
86 
87 	if (lan966x_xdp_present(lan966x))
88 		pp_params.dma_dir = DMA_BIDIRECTIONAL;
89 
90 	rx->page_pool = page_pool_create(&pp_params);
91 
92 	for (int i = 0; i < lan966x->num_phys_ports; ++i) {
93 		struct lan966x_port *port;
94 
95 		if (!lan966x->ports[i])
96 			continue;
97 
98 		port = lan966x->ports[i];
99 		xdp_rxq_info_unreg_mem_model(&port->xdp_rxq);
100 		xdp_rxq_info_reg_mem_model(&port->xdp_rxq, MEM_TYPE_PAGE_POOL,
101 					   rx->page_pool);
102 	}
103 
104 	return PTR_ERR_OR_ZERO(rx->page_pool);
105 }
106 
107 static int lan966x_fdma_rx_alloc(struct lan966x_rx *rx)
108 {
109 	struct lan966x *lan966x = rx->lan966x;
110 	struct fdma *fdma = &rx->fdma;
111 	struct lan966x_rx_dcb *dcb;
112 	struct lan966x_db *db;
113 	struct page *page;
114 	int i, j;
115 	int size;
116 
117 	if (lan966x_fdma_rx_alloc_page_pool(rx))
118 		return PTR_ERR(rx->page_pool);
119 
120 	/* calculate how many pages are needed to allocate the dcbs */
121 	size = sizeof(struct lan966x_rx_dcb) * fdma->n_dcbs;
122 	size = ALIGN(size, PAGE_SIZE);
123 
124 	rx->dcbs = dma_alloc_coherent(lan966x->dev, size, &rx->dma, GFP_KERNEL);
125 	if (!rx->dcbs)
126 		return -ENOMEM;
127 
128 	rx->last_entry = rx->dcbs;
129 	fdma->db_index = 0;
130 	fdma->dcb_index = 0;
131 
132 	/* Now for each dcb allocate the dbs */
133 	for (i = 0; i < fdma->n_dcbs; ++i) {
134 		dcb = &rx->dcbs[i];
135 		dcb->info = 0;
136 
137 		/* For each db allocate a page and map it to the DB dataptr. */
138 		for (j = 0; j < fdma->n_dbs; ++j) {
139 			db = &dcb->db[j];
140 			page = lan966x_fdma_rx_alloc_page(rx, db);
141 			if (!page)
142 				return -ENOMEM;
143 
144 			db->status = 0;
145 			rx->page[i][j] = page;
146 		}
147 
148 		lan966x_fdma_rx_add_dcb(rx, dcb, rx->dma + sizeof(*dcb) * i);
149 	}
150 
151 	return 0;
152 }
153 
154 static void lan966x_fdma_rx_advance_dcb(struct lan966x_rx *rx)
155 {
156 	struct fdma *fdma = &rx->fdma;
157 
158 	fdma->dcb_index++;
159 	fdma->dcb_index &= fdma->n_dcbs - 1;
160 }
161 
162 static void lan966x_fdma_rx_free(struct lan966x_rx *rx)
163 {
164 	struct lan966x *lan966x = rx->lan966x;
165 	struct fdma *fdma = &rx->fdma;
166 	u32 size;
167 
168 	/* Now it is possible to do the cleanup of dcb */
169 	size = sizeof(struct lan966x_tx_dcb) * fdma->n_dcbs;
170 	size = ALIGN(size, PAGE_SIZE);
171 	dma_free_coherent(lan966x->dev, size, rx->dcbs, rx->dma);
172 }
173 
174 static void lan966x_fdma_rx_start(struct lan966x_rx *rx)
175 {
176 	struct lan966x *lan966x = rx->lan966x;
177 	struct fdma *fdma = &rx->fdma;
178 	u32 mask;
179 
180 	/* When activating a channel, first is required to write the first DCB
181 	 * address and then to activate it
182 	 */
183 	lan_wr(lower_32_bits((u64)rx->dma), lan966x,
184 	       FDMA_DCB_LLP(fdma->channel_id));
185 	lan_wr(upper_32_bits((u64)rx->dma), lan966x,
186 	       FDMA_DCB_LLP1(fdma->channel_id));
187 
188 	lan_wr(FDMA_CH_CFG_CH_DCB_DB_CNT_SET(fdma->n_dbs) |
189 	       FDMA_CH_CFG_CH_INTR_DB_EOF_ONLY_SET(1) |
190 	       FDMA_CH_CFG_CH_INJ_PORT_SET(0) |
191 	       FDMA_CH_CFG_CH_MEM_SET(1),
192 	       lan966x, FDMA_CH_CFG(fdma->channel_id));
193 
194 	/* Start fdma */
195 	lan_rmw(FDMA_PORT_CTRL_XTR_STOP_SET(0),
196 		FDMA_PORT_CTRL_XTR_STOP,
197 		lan966x, FDMA_PORT_CTRL(0));
198 
199 	/* Enable interrupts */
200 	mask = lan_rd(lan966x, FDMA_INTR_DB_ENA);
201 	mask = FDMA_INTR_DB_ENA_INTR_DB_ENA_GET(mask);
202 	mask |= BIT(fdma->channel_id);
203 	lan_rmw(FDMA_INTR_DB_ENA_INTR_DB_ENA_SET(mask),
204 		FDMA_INTR_DB_ENA_INTR_DB_ENA,
205 		lan966x, FDMA_INTR_DB_ENA);
206 
207 	/* Activate the channel */
208 	lan_rmw(FDMA_CH_ACTIVATE_CH_ACTIVATE_SET(BIT(fdma->channel_id)),
209 		FDMA_CH_ACTIVATE_CH_ACTIVATE,
210 		lan966x, FDMA_CH_ACTIVATE);
211 }
212 
213 static void lan966x_fdma_rx_disable(struct lan966x_rx *rx)
214 {
215 	struct lan966x *lan966x = rx->lan966x;
216 	struct fdma *fdma = &rx->fdma;
217 	u32 val;
218 
219 	/* Disable the channel */
220 	lan_rmw(FDMA_CH_DISABLE_CH_DISABLE_SET(BIT(fdma->channel_id)),
221 		FDMA_CH_DISABLE_CH_DISABLE,
222 		lan966x, FDMA_CH_DISABLE);
223 
224 	readx_poll_timeout_atomic(lan966x_fdma_channel_active, lan966x,
225 				  val, !(val & BIT(fdma->channel_id)),
226 				  READL_SLEEP_US, READL_TIMEOUT_US);
227 
228 	lan_rmw(FDMA_CH_DB_DISCARD_DB_DISCARD_SET(BIT(fdma->channel_id)),
229 		FDMA_CH_DB_DISCARD_DB_DISCARD,
230 		lan966x, FDMA_CH_DB_DISCARD);
231 }
232 
233 static void lan966x_fdma_rx_reload(struct lan966x_rx *rx)
234 {
235 	struct lan966x *lan966x = rx->lan966x;
236 
237 	lan_rmw(FDMA_CH_RELOAD_CH_RELOAD_SET(BIT(rx->fdma.channel_id)),
238 		FDMA_CH_RELOAD_CH_RELOAD,
239 		lan966x, FDMA_CH_RELOAD);
240 }
241 
242 static void lan966x_fdma_tx_add_dcb(struct lan966x_tx *tx,
243 				    struct lan966x_tx_dcb *dcb)
244 {
245 	dcb->nextptr = FDMA_DCB_INVALID_DATA;
246 	dcb->info = 0;
247 }
248 
249 static int lan966x_fdma_tx_alloc(struct lan966x_tx *tx)
250 {
251 	struct lan966x *lan966x = tx->lan966x;
252 	struct fdma *fdma = &tx->fdma;
253 	struct lan966x_tx_dcb *dcb;
254 	struct lan966x_db *db;
255 	int size;
256 	int i, j;
257 
258 	tx->dcbs_buf = kcalloc(fdma->n_dcbs, sizeof(struct lan966x_tx_dcb_buf),
259 			       GFP_KERNEL);
260 	if (!tx->dcbs_buf)
261 		return -ENOMEM;
262 
263 	/* calculate how many pages are needed to allocate the dcbs */
264 	size = sizeof(struct lan966x_tx_dcb) * fdma->n_dcbs;
265 	size = ALIGN(size, PAGE_SIZE);
266 	tx->dcbs = dma_alloc_coherent(lan966x->dev, size, &tx->dma, GFP_KERNEL);
267 	if (!tx->dcbs)
268 		goto out;
269 
270 	/* Now for each dcb allocate the db */
271 	for (i = 0; i < fdma->n_dcbs; ++i) {
272 		dcb = &tx->dcbs[i];
273 
274 		for (j = 0; j < fdma->n_dbs; ++j) {
275 			db = &dcb->db[j];
276 			db->dataptr = 0;
277 			db->status = 0;
278 		}
279 
280 		lan966x_fdma_tx_add_dcb(tx, dcb);
281 	}
282 
283 	return 0;
284 
285 out:
286 	kfree(tx->dcbs_buf);
287 	return -ENOMEM;
288 }
289 
290 static void lan966x_fdma_tx_free(struct lan966x_tx *tx)
291 {
292 	struct lan966x *lan966x = tx->lan966x;
293 	struct fdma *fdma = &tx->fdma;
294 	int size;
295 
296 	kfree(tx->dcbs_buf);
297 
298 	size = sizeof(struct lan966x_tx_dcb) * fdma->n_dcbs;
299 	size = ALIGN(size, PAGE_SIZE);
300 	dma_free_coherent(lan966x->dev, size, tx->dcbs, tx->dma);
301 }
302 
303 static void lan966x_fdma_tx_activate(struct lan966x_tx *tx)
304 {
305 	struct lan966x *lan966x = tx->lan966x;
306 	struct fdma *fdma = &tx->fdma;
307 	u32 mask;
308 
309 	/* When activating a channel, first is required to write the first DCB
310 	 * address and then to activate it
311 	 */
312 	lan_wr(lower_32_bits((u64)tx->dma), lan966x,
313 	       FDMA_DCB_LLP(fdma->channel_id));
314 	lan_wr(upper_32_bits((u64)tx->dma), lan966x,
315 	       FDMA_DCB_LLP1(fdma->channel_id));
316 
317 	lan_wr(FDMA_CH_CFG_CH_DCB_DB_CNT_SET(fdma->n_dbs) |
318 	       FDMA_CH_CFG_CH_INTR_DB_EOF_ONLY_SET(1) |
319 	       FDMA_CH_CFG_CH_INJ_PORT_SET(0) |
320 	       FDMA_CH_CFG_CH_MEM_SET(1),
321 	       lan966x, FDMA_CH_CFG(fdma->channel_id));
322 
323 	/* Start fdma */
324 	lan_rmw(FDMA_PORT_CTRL_INJ_STOP_SET(0),
325 		FDMA_PORT_CTRL_INJ_STOP,
326 		lan966x, FDMA_PORT_CTRL(0));
327 
328 	/* Enable interrupts */
329 	mask = lan_rd(lan966x, FDMA_INTR_DB_ENA);
330 	mask = FDMA_INTR_DB_ENA_INTR_DB_ENA_GET(mask);
331 	mask |= BIT(fdma->channel_id);
332 	lan_rmw(FDMA_INTR_DB_ENA_INTR_DB_ENA_SET(mask),
333 		FDMA_INTR_DB_ENA_INTR_DB_ENA,
334 		lan966x, FDMA_INTR_DB_ENA);
335 
336 	/* Activate the channel */
337 	lan_rmw(FDMA_CH_ACTIVATE_CH_ACTIVATE_SET(BIT(fdma->channel_id)),
338 		FDMA_CH_ACTIVATE_CH_ACTIVATE,
339 		lan966x, FDMA_CH_ACTIVATE);
340 }
341 
342 static void lan966x_fdma_tx_disable(struct lan966x_tx *tx)
343 {
344 	struct lan966x *lan966x = tx->lan966x;
345 	struct fdma *fdma = &tx->fdma;
346 	u32 val;
347 
348 	/* Disable the channel */
349 	lan_rmw(FDMA_CH_DISABLE_CH_DISABLE_SET(BIT(fdma->channel_id)),
350 		FDMA_CH_DISABLE_CH_DISABLE,
351 		lan966x, FDMA_CH_DISABLE);
352 
353 	readx_poll_timeout_atomic(lan966x_fdma_channel_active, lan966x,
354 				  val, !(val & BIT(fdma->channel_id)),
355 				  READL_SLEEP_US, READL_TIMEOUT_US);
356 
357 	lan_rmw(FDMA_CH_DB_DISCARD_DB_DISCARD_SET(BIT(fdma->channel_id)),
358 		FDMA_CH_DB_DISCARD_DB_DISCARD,
359 		lan966x, FDMA_CH_DB_DISCARD);
360 
361 	tx->activated = false;
362 	tx->last_in_use = -1;
363 }
364 
365 static void lan966x_fdma_tx_reload(struct lan966x_tx *tx)
366 {
367 	struct lan966x *lan966x = tx->lan966x;
368 
369 	/* Write the registers to reload the channel */
370 	lan_rmw(FDMA_CH_RELOAD_CH_RELOAD_SET(BIT(tx->fdma.channel_id)),
371 		FDMA_CH_RELOAD_CH_RELOAD,
372 		lan966x, FDMA_CH_RELOAD);
373 }
374 
375 static void lan966x_fdma_wakeup_netdev(struct lan966x *lan966x)
376 {
377 	struct lan966x_port *port;
378 	int i;
379 
380 	for (i = 0; i < lan966x->num_phys_ports; ++i) {
381 		port = lan966x->ports[i];
382 		if (!port)
383 			continue;
384 
385 		if (netif_queue_stopped(port->dev))
386 			netif_wake_queue(port->dev);
387 	}
388 }
389 
390 static void lan966x_fdma_stop_netdev(struct lan966x *lan966x)
391 {
392 	struct lan966x_port *port;
393 	int i;
394 
395 	for (i = 0; i < lan966x->num_phys_ports; ++i) {
396 		port = lan966x->ports[i];
397 		if (!port)
398 			continue;
399 
400 		netif_stop_queue(port->dev);
401 	}
402 }
403 
404 static void lan966x_fdma_tx_clear_buf(struct lan966x *lan966x, int weight)
405 {
406 	struct lan966x_tx *tx = &lan966x->tx;
407 	struct lan966x_rx *rx = &lan966x->rx;
408 	struct lan966x_tx_dcb_buf *dcb_buf;
409 	struct xdp_frame_bulk bq;
410 	struct lan966x_db *db;
411 	unsigned long flags;
412 	bool clear = false;
413 	int i;
414 
415 	xdp_frame_bulk_init(&bq);
416 
417 	spin_lock_irqsave(&lan966x->tx_lock, flags);
418 	for (i = 0; i < tx->fdma.n_dcbs; ++i) {
419 		dcb_buf = &tx->dcbs_buf[i];
420 
421 		if (!dcb_buf->used)
422 			continue;
423 
424 		db = &tx->dcbs[i].db[0];
425 		if (!(db->status & FDMA_DCB_STATUS_DONE))
426 			continue;
427 
428 		dcb_buf->dev->stats.tx_packets++;
429 		dcb_buf->dev->stats.tx_bytes += dcb_buf->len;
430 
431 		dcb_buf->used = false;
432 		if (dcb_buf->use_skb) {
433 			dma_unmap_single(lan966x->dev,
434 					 dcb_buf->dma_addr,
435 					 dcb_buf->len,
436 					 DMA_TO_DEVICE);
437 
438 			if (!dcb_buf->ptp)
439 				napi_consume_skb(dcb_buf->data.skb, weight);
440 		} else {
441 			if (dcb_buf->xdp_ndo)
442 				dma_unmap_single(lan966x->dev,
443 						 dcb_buf->dma_addr,
444 						 dcb_buf->len,
445 						 DMA_TO_DEVICE);
446 
447 			if (dcb_buf->xdp_ndo)
448 				xdp_return_frame_bulk(dcb_buf->data.xdpf, &bq);
449 			else
450 				page_pool_recycle_direct(rx->page_pool,
451 							 dcb_buf->data.page);
452 		}
453 
454 		clear = true;
455 	}
456 
457 	xdp_flush_frame_bulk(&bq);
458 
459 	if (clear)
460 		lan966x_fdma_wakeup_netdev(lan966x);
461 
462 	spin_unlock_irqrestore(&lan966x->tx_lock, flags);
463 }
464 
465 static bool lan966x_fdma_rx_more_frames(struct lan966x_rx *rx)
466 {
467 	struct fdma *fdma = &rx->fdma;
468 	struct lan966x_db *db;
469 
470 	/* Check if there is any data */
471 	db = &rx->dcbs[fdma->dcb_index].db[fdma->db_index];
472 	if (unlikely(!(db->status & FDMA_DCB_STATUS_DONE)))
473 		return false;
474 
475 	return true;
476 }
477 
478 static int lan966x_fdma_rx_check_frame(struct lan966x_rx *rx, u64 *src_port)
479 {
480 	struct lan966x *lan966x = rx->lan966x;
481 	struct fdma *fdma = &rx->fdma;
482 	struct lan966x_port *port;
483 	struct lan966x_db *db;
484 	struct page *page;
485 
486 	db = &rx->dcbs[fdma->dcb_index].db[fdma->db_index];
487 	page = rx->page[fdma->dcb_index][fdma->db_index];
488 	if (unlikely(!page))
489 		return FDMA_ERROR;
490 
491 	dma_sync_single_for_cpu(lan966x->dev,
492 				(dma_addr_t)db->dataptr + XDP_PACKET_HEADROOM,
493 				FDMA_DCB_STATUS_BLOCKL(db->status),
494 				DMA_FROM_DEVICE);
495 
496 	lan966x_ifh_get_src_port(page_address(page) + XDP_PACKET_HEADROOM,
497 				 src_port);
498 	if (WARN_ON(*src_port >= lan966x->num_phys_ports))
499 		return FDMA_ERROR;
500 
501 	port = lan966x->ports[*src_port];
502 	if (!lan966x_xdp_port_present(port))
503 		return FDMA_PASS;
504 
505 	return lan966x_xdp_run(port, page, FDMA_DCB_STATUS_BLOCKL(db->status));
506 }
507 
508 static struct sk_buff *lan966x_fdma_rx_get_frame(struct lan966x_rx *rx,
509 						 u64 src_port)
510 {
511 	struct lan966x *lan966x = rx->lan966x;
512 	struct fdma *fdma = &rx->fdma;
513 	struct lan966x_db *db;
514 	struct sk_buff *skb;
515 	struct page *page;
516 	u64 timestamp;
517 
518 	/* Get the received frame and unmap it */
519 	db = &rx->dcbs[fdma->dcb_index].db[fdma->db_index];
520 	page = rx->page[fdma->dcb_index][fdma->db_index];
521 
522 	skb = build_skb(page_address(page), PAGE_SIZE << rx->page_order);
523 	if (unlikely(!skb))
524 		goto free_page;
525 
526 	skb_mark_for_recycle(skb);
527 
528 	skb_reserve(skb, XDP_PACKET_HEADROOM);
529 	skb_put(skb, FDMA_DCB_STATUS_BLOCKL(db->status));
530 
531 	lan966x_ifh_get_timestamp(skb->data, &timestamp);
532 
533 	skb->dev = lan966x->ports[src_port]->dev;
534 	skb_pull(skb, IFH_LEN_BYTES);
535 
536 	if (likely(!(skb->dev->features & NETIF_F_RXFCS)))
537 		skb_trim(skb, skb->len - ETH_FCS_LEN);
538 
539 	lan966x_ptp_rxtstamp(lan966x, skb, src_port, timestamp);
540 	skb->protocol = eth_type_trans(skb, skb->dev);
541 
542 	if (lan966x->bridge_mask & BIT(src_port)) {
543 		skb->offload_fwd_mark = 1;
544 
545 		skb_reset_network_header(skb);
546 		if (!lan966x_hw_offload(lan966x, src_port, skb))
547 			skb->offload_fwd_mark = 0;
548 	}
549 
550 	skb->dev->stats.rx_bytes += skb->len;
551 	skb->dev->stats.rx_packets++;
552 
553 	return skb;
554 
555 free_page:
556 	page_pool_recycle_direct(rx->page_pool, page);
557 
558 	return NULL;
559 }
560 
561 static int lan966x_fdma_napi_poll(struct napi_struct *napi, int weight)
562 {
563 	struct lan966x *lan966x = container_of(napi, struct lan966x, napi);
564 	struct lan966x_rx *rx = &lan966x->rx;
565 	struct lan966x_rx_dcb *old_dcb;
566 	struct fdma *fdma = &rx->fdma;
567 	int dcb_reload, counter = 0;
568 	struct lan966x_db *db;
569 	bool redirect = false;
570 	struct sk_buff *skb;
571 	struct page *page;
572 	u64 src_port;
573 	u64 nextptr;
574 
575 	dcb_reload = fdma->dcb_index;
576 
577 	lan966x_fdma_tx_clear_buf(lan966x, weight);
578 
579 	/* Get all received skb */
580 	while (counter < weight) {
581 		if (!lan966x_fdma_rx_more_frames(rx))
582 			break;
583 
584 		counter++;
585 
586 		switch (lan966x_fdma_rx_check_frame(rx, &src_port)) {
587 		case FDMA_PASS:
588 			break;
589 		case FDMA_ERROR:
590 			lan966x_fdma_rx_free_page(rx);
591 			lan966x_fdma_rx_advance_dcb(rx);
592 			goto allocate_new;
593 		case FDMA_REDIRECT:
594 			redirect = true;
595 			fallthrough;
596 		case FDMA_TX:
597 			lan966x_fdma_rx_advance_dcb(rx);
598 			continue;
599 		case FDMA_DROP:
600 			lan966x_fdma_rx_free_page(rx);
601 			lan966x_fdma_rx_advance_dcb(rx);
602 			continue;
603 		}
604 
605 		skb = lan966x_fdma_rx_get_frame(rx, src_port);
606 		lan966x_fdma_rx_advance_dcb(rx);
607 		if (!skb)
608 			goto allocate_new;
609 
610 		napi_gro_receive(&lan966x->napi, skb);
611 	}
612 
613 allocate_new:
614 	/* Allocate new pages and map them */
615 	while (dcb_reload != fdma->dcb_index) {
616 		db = &rx->dcbs[dcb_reload].db[fdma->db_index];
617 		page = lan966x_fdma_rx_alloc_page(rx, db);
618 		if (unlikely(!page))
619 			break;
620 		rx->page[dcb_reload][fdma->db_index] = page;
621 
622 		old_dcb = &rx->dcbs[dcb_reload];
623 		dcb_reload++;
624 		dcb_reload &= fdma->n_dcbs - 1;
625 
626 		nextptr = rx->dma + ((unsigned long)old_dcb -
627 				     (unsigned long)rx->dcbs);
628 		lan966x_fdma_rx_add_dcb(rx, old_dcb, nextptr);
629 		lan966x_fdma_rx_reload(rx);
630 	}
631 
632 	if (redirect)
633 		xdp_do_flush();
634 
635 	if (counter < weight && napi_complete_done(napi, counter))
636 		lan_wr(0xff, lan966x, FDMA_INTR_DB_ENA);
637 
638 	return counter;
639 }
640 
641 irqreturn_t lan966x_fdma_irq_handler(int irq, void *args)
642 {
643 	struct lan966x *lan966x = args;
644 	u32 db, err, err_type;
645 
646 	db = lan_rd(lan966x, FDMA_INTR_DB);
647 	err = lan_rd(lan966x, FDMA_INTR_ERR);
648 
649 	if (db) {
650 		lan_wr(0, lan966x, FDMA_INTR_DB_ENA);
651 		lan_wr(db, lan966x, FDMA_INTR_DB);
652 
653 		napi_schedule(&lan966x->napi);
654 	}
655 
656 	if (err) {
657 		err_type = lan_rd(lan966x, FDMA_ERRORS);
658 
659 		WARN(1, "Unexpected error: %d, error_type: %d\n", err, err_type);
660 
661 		lan_wr(err, lan966x, FDMA_INTR_ERR);
662 		lan_wr(err_type, lan966x, FDMA_ERRORS);
663 	}
664 
665 	return IRQ_HANDLED;
666 }
667 
668 static int lan966x_fdma_get_next_dcb(struct lan966x_tx *tx)
669 {
670 	struct lan966x_tx_dcb_buf *dcb_buf;
671 	struct fdma *fdma = &tx->fdma;
672 	int i;
673 
674 	for (i = 0; i < fdma->n_dcbs; ++i) {
675 		dcb_buf = &tx->dcbs_buf[i];
676 		if (!dcb_buf->used && i != tx->last_in_use)
677 			return i;
678 	}
679 
680 	return -1;
681 }
682 
683 static void lan966x_fdma_tx_setup_dcb(struct lan966x_tx *tx,
684 				      int next_to_use, int len,
685 				      dma_addr_t dma_addr)
686 {
687 	struct lan966x_tx_dcb *next_dcb;
688 	struct lan966x_db *next_db;
689 
690 	next_dcb = &tx->dcbs[next_to_use];
691 	next_dcb->nextptr = FDMA_DCB_INVALID_DATA;
692 
693 	next_db = &next_dcb->db[0];
694 	next_db->dataptr = dma_addr;
695 	next_db->status = FDMA_DCB_STATUS_SOF |
696 			  FDMA_DCB_STATUS_EOF |
697 			  FDMA_DCB_STATUS_INTR |
698 			  FDMA_DCB_STATUS_BLOCKO(0) |
699 			  FDMA_DCB_STATUS_BLOCKL(len);
700 }
701 
702 static void lan966x_fdma_tx_start(struct lan966x_tx *tx, int next_to_use)
703 {
704 	struct lan966x *lan966x = tx->lan966x;
705 	struct lan966x_tx_dcb *dcb;
706 
707 	if (likely(lan966x->tx.activated)) {
708 		/* Connect current dcb to the next db */
709 		dcb = &tx->dcbs[tx->last_in_use];
710 		dcb->nextptr = tx->dma + (next_to_use *
711 					  sizeof(struct lan966x_tx_dcb));
712 
713 		lan966x_fdma_tx_reload(tx);
714 	} else {
715 		/* Because it is first time, then just activate */
716 		lan966x->tx.activated = true;
717 		lan966x_fdma_tx_activate(tx);
718 	}
719 
720 	/* Move to next dcb because this last in use */
721 	tx->last_in_use = next_to_use;
722 }
723 
724 int lan966x_fdma_xmit_xdpf(struct lan966x_port *port, void *ptr, u32 len)
725 {
726 	struct lan966x *lan966x = port->lan966x;
727 	struct lan966x_tx_dcb_buf *next_dcb_buf;
728 	struct lan966x_tx *tx = &lan966x->tx;
729 	struct xdp_frame *xdpf;
730 	dma_addr_t dma_addr;
731 	struct page *page;
732 	int next_to_use;
733 	__be32 *ifh;
734 	int ret = 0;
735 
736 	spin_lock(&lan966x->tx_lock);
737 
738 	/* Get next index */
739 	next_to_use = lan966x_fdma_get_next_dcb(tx);
740 	if (next_to_use < 0) {
741 		netif_stop_queue(port->dev);
742 		ret = NETDEV_TX_BUSY;
743 		goto out;
744 	}
745 
746 	/* Get the next buffer */
747 	next_dcb_buf = &tx->dcbs_buf[next_to_use];
748 
749 	/* Generate new IFH */
750 	if (!len) {
751 		xdpf = ptr;
752 
753 		if (xdpf->headroom < IFH_LEN_BYTES) {
754 			ret = NETDEV_TX_OK;
755 			goto out;
756 		}
757 
758 		ifh = xdpf->data - IFH_LEN_BYTES;
759 		memset(ifh, 0x0, sizeof(__be32) * IFH_LEN);
760 		lan966x_ifh_set_bypass(ifh, 1);
761 		lan966x_ifh_set_port(ifh, BIT_ULL(port->chip_port));
762 
763 		dma_addr = dma_map_single(lan966x->dev,
764 					  xdpf->data - IFH_LEN_BYTES,
765 					  xdpf->len + IFH_LEN_BYTES,
766 					  DMA_TO_DEVICE);
767 		if (dma_mapping_error(lan966x->dev, dma_addr)) {
768 			ret = NETDEV_TX_OK;
769 			goto out;
770 		}
771 
772 		next_dcb_buf->data.xdpf = xdpf;
773 		next_dcb_buf->len = xdpf->len + IFH_LEN_BYTES;
774 
775 		/* Setup next dcb */
776 		lan966x_fdma_tx_setup_dcb(tx, next_to_use,
777 					  xdpf->len + IFH_LEN_BYTES,
778 					  dma_addr);
779 	} else {
780 		page = ptr;
781 
782 		ifh = page_address(page) + XDP_PACKET_HEADROOM;
783 		memset(ifh, 0x0, sizeof(__be32) * IFH_LEN);
784 		lan966x_ifh_set_bypass(ifh, 1);
785 		lan966x_ifh_set_port(ifh, BIT_ULL(port->chip_port));
786 
787 		dma_addr = page_pool_get_dma_addr(page);
788 		dma_sync_single_for_device(lan966x->dev,
789 					   dma_addr + XDP_PACKET_HEADROOM,
790 					   len + IFH_LEN_BYTES,
791 					   DMA_TO_DEVICE);
792 
793 		next_dcb_buf->data.page = page;
794 		next_dcb_buf->len = len + IFH_LEN_BYTES;
795 
796 		/* Setup next dcb */
797 		lan966x_fdma_tx_setup_dcb(tx, next_to_use,
798 					  len + IFH_LEN_BYTES,
799 					  dma_addr + XDP_PACKET_HEADROOM);
800 	}
801 
802 	/* Fill up the buffer */
803 	next_dcb_buf->use_skb = false;
804 	next_dcb_buf->xdp_ndo = !len;
805 	next_dcb_buf->dma_addr = dma_addr;
806 	next_dcb_buf->used = true;
807 	next_dcb_buf->ptp = false;
808 	next_dcb_buf->dev = port->dev;
809 
810 	/* Start the transmission */
811 	lan966x_fdma_tx_start(tx, next_to_use);
812 
813 out:
814 	spin_unlock(&lan966x->tx_lock);
815 
816 	return ret;
817 }
818 
819 int lan966x_fdma_xmit(struct sk_buff *skb, __be32 *ifh, struct net_device *dev)
820 {
821 	struct lan966x_port *port = netdev_priv(dev);
822 	struct lan966x *lan966x = port->lan966x;
823 	struct lan966x_tx_dcb_buf *next_dcb_buf;
824 	struct lan966x_tx *tx = &lan966x->tx;
825 	int needed_headroom;
826 	int needed_tailroom;
827 	dma_addr_t dma_addr;
828 	int next_to_use;
829 	int err;
830 
831 	/* Get next index */
832 	next_to_use = lan966x_fdma_get_next_dcb(tx);
833 	if (next_to_use < 0) {
834 		netif_stop_queue(dev);
835 		return NETDEV_TX_BUSY;
836 	}
837 
838 	if (skb_put_padto(skb, ETH_ZLEN)) {
839 		dev->stats.tx_dropped++;
840 		return NETDEV_TX_OK;
841 	}
842 
843 	/* skb processing */
844 	needed_headroom = max_t(int, IFH_LEN_BYTES - skb_headroom(skb), 0);
845 	needed_tailroom = max_t(int, ETH_FCS_LEN - skb_tailroom(skb), 0);
846 	if (needed_headroom || needed_tailroom || skb_header_cloned(skb)) {
847 		err = pskb_expand_head(skb, needed_headroom, needed_tailroom,
848 				       GFP_ATOMIC);
849 		if (unlikely(err)) {
850 			dev->stats.tx_dropped++;
851 			err = NETDEV_TX_OK;
852 			goto release;
853 		}
854 	}
855 
856 	skb_tx_timestamp(skb);
857 	skb_push(skb, IFH_LEN_BYTES);
858 	memcpy(skb->data, ifh, IFH_LEN_BYTES);
859 	skb_put(skb, 4);
860 
861 	dma_addr = dma_map_single(lan966x->dev, skb->data, skb->len,
862 				  DMA_TO_DEVICE);
863 	if (dma_mapping_error(lan966x->dev, dma_addr)) {
864 		dev->stats.tx_dropped++;
865 		err = NETDEV_TX_OK;
866 		goto release;
867 	}
868 
869 	/* Setup next dcb */
870 	lan966x_fdma_tx_setup_dcb(tx, next_to_use, skb->len, dma_addr);
871 
872 	/* Fill up the buffer */
873 	next_dcb_buf = &tx->dcbs_buf[next_to_use];
874 	next_dcb_buf->use_skb = true;
875 	next_dcb_buf->data.skb = skb;
876 	next_dcb_buf->xdp_ndo = false;
877 	next_dcb_buf->len = skb->len;
878 	next_dcb_buf->dma_addr = dma_addr;
879 	next_dcb_buf->used = true;
880 	next_dcb_buf->ptp = false;
881 	next_dcb_buf->dev = dev;
882 
883 	if (skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP &&
884 	    LAN966X_SKB_CB(skb)->rew_op == IFH_REW_OP_TWO_STEP_PTP)
885 		next_dcb_buf->ptp = true;
886 
887 	/* Start the transmission */
888 	lan966x_fdma_tx_start(tx, next_to_use);
889 
890 	return NETDEV_TX_OK;
891 
892 release:
893 	if (skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP &&
894 	    LAN966X_SKB_CB(skb)->rew_op == IFH_REW_OP_TWO_STEP_PTP)
895 		lan966x_ptp_txtstamp_release(port, skb);
896 
897 	dev_kfree_skb_any(skb);
898 	return err;
899 }
900 
901 static int lan966x_fdma_get_max_mtu(struct lan966x *lan966x)
902 {
903 	int max_mtu = 0;
904 	int i;
905 
906 	for (i = 0; i < lan966x->num_phys_ports; ++i) {
907 		struct lan966x_port *port;
908 		int mtu;
909 
910 		port = lan966x->ports[i];
911 		if (!port)
912 			continue;
913 
914 		mtu = lan_rd(lan966x, DEV_MAC_MAXLEN_CFG(port->chip_port));
915 		if (mtu > max_mtu)
916 			max_mtu = mtu;
917 	}
918 
919 	return max_mtu;
920 }
921 
922 static int lan966x_qsys_sw_status(struct lan966x *lan966x)
923 {
924 	return lan_rd(lan966x, QSYS_SW_STATUS(CPU_PORT));
925 }
926 
927 static int lan966x_fdma_reload(struct lan966x *lan966x, int new_mtu)
928 {
929 	struct page_pool *page_pool;
930 	dma_addr_t rx_dma;
931 	void *rx_dcbs;
932 	u32 size;
933 	int err;
934 
935 	/* Store these for later to free them */
936 	rx_dma = lan966x->rx.dma;
937 	rx_dcbs = lan966x->rx.dcbs;
938 	page_pool = lan966x->rx.page_pool;
939 
940 	napi_synchronize(&lan966x->napi);
941 	napi_disable(&lan966x->napi);
942 	lan966x_fdma_stop_netdev(lan966x);
943 
944 	lan966x_fdma_rx_disable(&lan966x->rx);
945 	lan966x_fdma_rx_free_pages(&lan966x->rx);
946 	lan966x->rx.page_order = round_up(new_mtu, PAGE_SIZE) / PAGE_SIZE - 1;
947 	lan966x->rx.max_mtu = new_mtu;
948 	err = lan966x_fdma_rx_alloc(&lan966x->rx);
949 	if (err)
950 		goto restore;
951 	lan966x_fdma_rx_start(&lan966x->rx);
952 
953 	size = sizeof(struct lan966x_rx_dcb) * lan966x->rx.fdma.n_dcbs;
954 	size = ALIGN(size, PAGE_SIZE);
955 	dma_free_coherent(lan966x->dev, size, rx_dcbs, rx_dma);
956 
957 	page_pool_destroy(page_pool);
958 
959 	lan966x_fdma_wakeup_netdev(lan966x);
960 	napi_enable(&lan966x->napi);
961 
962 	return err;
963 restore:
964 	lan966x->rx.page_pool = page_pool;
965 	lan966x->rx.dma = rx_dma;
966 	lan966x->rx.dcbs = rx_dcbs;
967 	lan966x_fdma_rx_start(&lan966x->rx);
968 
969 	return err;
970 }
971 
972 static int lan966x_fdma_get_max_frame(struct lan966x *lan966x)
973 {
974 	return lan966x_fdma_get_max_mtu(lan966x) +
975 	       IFH_LEN_BYTES +
976 	       SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) +
977 	       VLAN_HLEN * 2 +
978 	       XDP_PACKET_HEADROOM;
979 }
980 
981 static int __lan966x_fdma_reload(struct lan966x *lan966x, int max_mtu)
982 {
983 	int err;
984 	u32 val;
985 
986 	/* Disable the CPU port */
987 	lan_rmw(QSYS_SW_PORT_MODE_PORT_ENA_SET(0),
988 		QSYS_SW_PORT_MODE_PORT_ENA,
989 		lan966x, QSYS_SW_PORT_MODE(CPU_PORT));
990 
991 	/* Flush the CPU queues */
992 	readx_poll_timeout(lan966x_qsys_sw_status, lan966x,
993 			   val, !(QSYS_SW_STATUS_EQ_AVAIL_GET(val)),
994 			   READL_SLEEP_US, READL_TIMEOUT_US);
995 
996 	/* Add a sleep in case there are frames between the queues and the CPU
997 	 * port
998 	 */
999 	usleep_range(1000, 2000);
1000 
1001 	err = lan966x_fdma_reload(lan966x, max_mtu);
1002 
1003 	/* Enable back the CPU port */
1004 	lan_rmw(QSYS_SW_PORT_MODE_PORT_ENA_SET(1),
1005 		QSYS_SW_PORT_MODE_PORT_ENA,
1006 		lan966x,  QSYS_SW_PORT_MODE(CPU_PORT));
1007 
1008 	return err;
1009 }
1010 
1011 int lan966x_fdma_change_mtu(struct lan966x *lan966x)
1012 {
1013 	int max_mtu;
1014 
1015 	max_mtu = lan966x_fdma_get_max_frame(lan966x);
1016 	if (max_mtu == lan966x->rx.max_mtu)
1017 		return 0;
1018 
1019 	return __lan966x_fdma_reload(lan966x, max_mtu);
1020 }
1021 
1022 int lan966x_fdma_reload_page_pool(struct lan966x *lan966x)
1023 {
1024 	int max_mtu;
1025 
1026 	max_mtu = lan966x_fdma_get_max_frame(lan966x);
1027 	return __lan966x_fdma_reload(lan966x, max_mtu);
1028 }
1029 
1030 void lan966x_fdma_netdev_init(struct lan966x *lan966x, struct net_device *dev)
1031 {
1032 	if (lan966x->fdma_ndev)
1033 		return;
1034 
1035 	lan966x->fdma_ndev = dev;
1036 	netif_napi_add(dev, &lan966x->napi, lan966x_fdma_napi_poll);
1037 	napi_enable(&lan966x->napi);
1038 }
1039 
1040 void lan966x_fdma_netdev_deinit(struct lan966x *lan966x, struct net_device *dev)
1041 {
1042 	if (lan966x->fdma_ndev == dev) {
1043 		netif_napi_del(&lan966x->napi);
1044 		lan966x->fdma_ndev = NULL;
1045 	}
1046 }
1047 
1048 int lan966x_fdma_init(struct lan966x *lan966x)
1049 {
1050 	int err;
1051 
1052 	if (!lan966x->fdma)
1053 		return 0;
1054 
1055 	lan966x->rx.lan966x = lan966x;
1056 	lan966x->rx.fdma.channel_id = FDMA_XTR_CHANNEL;
1057 	lan966x->rx.fdma.n_dcbs = FDMA_DCB_MAX;
1058 	lan966x->rx.fdma.n_dbs = FDMA_RX_DCB_MAX_DBS;
1059 	lan966x->rx.max_mtu = lan966x_fdma_get_max_frame(lan966x);
1060 	lan966x->tx.lan966x = lan966x;
1061 	lan966x->tx.fdma.channel_id = FDMA_INJ_CHANNEL;
1062 	lan966x->tx.fdma.n_dcbs = FDMA_DCB_MAX;
1063 	lan966x->tx.fdma.n_dbs = FDMA_TX_DCB_MAX_DBS;
1064 	lan966x->tx.last_in_use = -1;
1065 
1066 	err = lan966x_fdma_rx_alloc(&lan966x->rx);
1067 	if (err)
1068 		return err;
1069 
1070 	err = lan966x_fdma_tx_alloc(&lan966x->tx);
1071 	if (err) {
1072 		lan966x_fdma_rx_free(&lan966x->rx);
1073 		return err;
1074 	}
1075 
1076 	lan966x_fdma_rx_start(&lan966x->rx);
1077 
1078 	return 0;
1079 }
1080 
1081 void lan966x_fdma_deinit(struct lan966x *lan966x)
1082 {
1083 	if (!lan966x->fdma)
1084 		return;
1085 
1086 	lan966x_fdma_rx_disable(&lan966x->rx);
1087 	lan966x_fdma_tx_disable(&lan966x->tx);
1088 
1089 	napi_synchronize(&lan966x->napi);
1090 	napi_disable(&lan966x->napi);
1091 
1092 	lan966x_fdma_rx_free_pages(&lan966x->rx);
1093 	lan966x_fdma_rx_free(&lan966x->rx);
1094 	page_pool_destroy(lan966x->rx.page_pool);
1095 	lan966x_fdma_tx_free(&lan966x->tx);
1096 }
1097