xref: /openbmc/linux/drivers/net/wan/fsl_ucc_hdlc.c (revision 65417d9f)
1 /* Freescale QUICC Engine HDLC Device Driver
2  *
3  * Copyright 2016 Freescale Semiconductor Inc.
4  *
5  * This program is free software; you can redistribute  it and/or modify it
6  * under  the terms of  the GNU General  Public License as published by the
7  * Free Software Foundation;  either version 2 of the  License, or (at your
8  * option) any later version.
9  */
10 
11 #include <linux/delay.h>
12 #include <linux/dma-mapping.h>
13 #include <linux/hdlc.h>
14 #include <linux/init.h>
15 #include <linux/interrupt.h>
16 #include <linux/io.h>
17 #include <linux/irq.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/netdevice.h>
21 #include <linux/of_address.h>
22 #include <linux/of_irq.h>
23 #include <linux/of_platform.h>
24 #include <linux/platform_device.h>
25 #include <linux/sched.h>
26 #include <linux/skbuff.h>
27 #include <linux/slab.h>
28 #include <linux/spinlock.h>
29 #include <linux/stddef.h>
30 #include <soc/fsl/qe/qe_tdm.h>
31 #include <uapi/linux/if_arp.h>
32 
33 #include "fsl_ucc_hdlc.h"
34 
35 #define DRV_DESC "Freescale QE UCC HDLC Driver"
36 #define DRV_NAME "ucc_hdlc"
37 
38 #define TDM_PPPOHT_SLIC_MAXIN
39 
40 static struct ucc_tdm_info utdm_primary_info = {
41 	.uf_info = {
42 		.tsa = 0,
43 		.cdp = 0,
44 		.cds = 1,
45 		.ctsp = 1,
46 		.ctss = 1,
47 		.revd = 0,
48 		.urfs = 256,
49 		.utfs = 256,
50 		.urfet = 128,
51 		.urfset = 192,
52 		.utfet = 128,
53 		.utftt = 0x40,
54 		.ufpt = 256,
55 		.mode = UCC_FAST_PROTOCOL_MODE_HDLC,
56 		.ttx_trx = UCC_FAST_GUMR_TRANSPARENT_TTX_TRX_NORMAL,
57 		.tenc = UCC_FAST_TX_ENCODING_NRZ,
58 		.renc = UCC_FAST_RX_ENCODING_NRZ,
59 		.tcrc = UCC_FAST_16_BIT_CRC,
60 		.synl = UCC_FAST_SYNC_LEN_NOT_USED,
61 	},
62 
63 	.si_info = {
64 #ifdef TDM_PPPOHT_SLIC_MAXIN
65 		.simr_rfsd = 1,
66 		.simr_tfsd = 2,
67 #else
68 		.simr_rfsd = 0,
69 		.simr_tfsd = 0,
70 #endif
71 		.simr_crt = 0,
72 		.simr_sl = 0,
73 		.simr_ce = 1,
74 		.simr_fe = 1,
75 		.simr_gm = 0,
76 	},
77 };
78 
79 static struct ucc_tdm_info utdm_info[MAX_HDLC_NUM];
80 
81 static int uhdlc_init(struct ucc_hdlc_private *priv)
82 {
83 	struct ucc_tdm_info *ut_info;
84 	struct ucc_fast_info *uf_info;
85 	u32 cecr_subblock;
86 	u16 bd_status;
87 	int ret, i;
88 	void *bd_buffer;
89 	dma_addr_t bd_dma_addr;
90 	u32 riptr;
91 	u32 tiptr;
92 	u32 gumr;
93 
94 	ut_info = priv->ut_info;
95 	uf_info = &ut_info->uf_info;
96 
97 	if (priv->tsa) {
98 		uf_info->tsa = 1;
99 		uf_info->ctsp = 1;
100 	}
101 
102 	/* This sets HPM register in CMXUCR register which configures a
103 	 * open drain connected HDLC bus
104 	 */
105 	if (priv->hdlc_bus)
106 		uf_info->brkpt_support = 1;
107 
108 	uf_info->uccm_mask = ((UCC_HDLC_UCCE_RXB | UCC_HDLC_UCCE_RXF |
109 				UCC_HDLC_UCCE_TXB) << 16);
110 
111 	ret = ucc_fast_init(uf_info, &priv->uccf);
112 	if (ret) {
113 		dev_err(priv->dev, "Failed to init uccf.");
114 		return ret;
115 	}
116 
117 	priv->uf_regs = priv->uccf->uf_regs;
118 	ucc_fast_disable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
119 
120 	/* Loopback mode */
121 	if (priv->loopback) {
122 		dev_info(priv->dev, "Loopback Mode\n");
123 		/* use the same clock when work in loopback */
124 		qe_setbrg(ut_info->uf_info.rx_clock, 20000000, 1);
125 
126 		gumr = ioread32be(&priv->uf_regs->gumr);
127 		gumr |= (UCC_FAST_GUMR_LOOPBACK | UCC_FAST_GUMR_CDS |
128 			 UCC_FAST_GUMR_TCI);
129 		gumr &= ~(UCC_FAST_GUMR_CTSP | UCC_FAST_GUMR_RSYN);
130 		iowrite32be(gumr, &priv->uf_regs->gumr);
131 	}
132 
133 	/* Initialize SI */
134 	if (priv->tsa)
135 		ucc_tdm_init(priv->utdm, priv->ut_info);
136 
137 	/* Write to QE CECR, UCCx channel to Stop Transmission */
138 	cecr_subblock = ucc_fast_get_qe_cr_subblock(uf_info->ucc_num);
139 	ret = qe_issue_cmd(QE_STOP_TX, cecr_subblock,
140 			   QE_CR_PROTOCOL_UNSPECIFIED, 0);
141 
142 	/* Set UPSMR normal mode (need fixed)*/
143 	iowrite32be(0, &priv->uf_regs->upsmr);
144 
145 	/* hdlc_bus mode */
146 	if (priv->hdlc_bus) {
147 		u32 upsmr;
148 
149 		dev_info(priv->dev, "HDLC bus Mode\n");
150 		upsmr = ioread32be(&priv->uf_regs->upsmr);
151 
152 		/* bus mode and retransmit enable, with collision window
153 		 * set to 8 bytes
154 		 */
155 		upsmr |= UCC_HDLC_UPSMR_RTE | UCC_HDLC_UPSMR_BUS |
156 				UCC_HDLC_UPSMR_CW8;
157 		iowrite32be(upsmr, &priv->uf_regs->upsmr);
158 
159 		/* explicitly disable CDS & CTSP */
160 		gumr = ioread32be(&priv->uf_regs->gumr);
161 		gumr &= ~(UCC_FAST_GUMR_CDS | UCC_FAST_GUMR_CTSP);
162 		/* set automatic sync to explicitly ignore CD signal */
163 		gumr |= UCC_FAST_GUMR_SYNL_AUTO;
164 		iowrite32be(gumr, &priv->uf_regs->gumr);
165 	}
166 
167 	priv->rx_ring_size = RX_BD_RING_LEN;
168 	priv->tx_ring_size = TX_BD_RING_LEN;
169 	/* Alloc Rx BD */
170 	priv->rx_bd_base = dma_alloc_coherent(priv->dev,
171 			RX_BD_RING_LEN * sizeof(struct qe_bd),
172 			&priv->dma_rx_bd, GFP_KERNEL);
173 
174 	if (!priv->rx_bd_base) {
175 		dev_err(priv->dev, "Cannot allocate MURAM memory for RxBDs\n");
176 		ret = -ENOMEM;
177 		goto free_uccf;
178 	}
179 
180 	/* Alloc Tx BD */
181 	priv->tx_bd_base = dma_alloc_coherent(priv->dev,
182 			TX_BD_RING_LEN * sizeof(struct qe_bd),
183 			&priv->dma_tx_bd, GFP_KERNEL);
184 
185 	if (!priv->tx_bd_base) {
186 		dev_err(priv->dev, "Cannot allocate MURAM memory for TxBDs\n");
187 		ret = -ENOMEM;
188 		goto free_rx_bd;
189 	}
190 
191 	/* Alloc parameter ram for ucc hdlc */
192 	priv->ucc_pram_offset = qe_muram_alloc(sizeof(struct ucc_hdlc_param),
193 				ALIGNMENT_OF_UCC_HDLC_PRAM);
194 
195 	if (priv->ucc_pram_offset < 0) {
196 		dev_err(priv->dev, "Can not allocate MURAM for hdlc parameter.\n");
197 		ret = -ENOMEM;
198 		goto free_tx_bd;
199 	}
200 
201 	priv->rx_skbuff = kzalloc(priv->rx_ring_size * sizeof(*priv->rx_skbuff),
202 				  GFP_KERNEL);
203 	if (!priv->rx_skbuff)
204 		goto free_ucc_pram;
205 
206 	priv->tx_skbuff = kzalloc(priv->tx_ring_size * sizeof(*priv->tx_skbuff),
207 				  GFP_KERNEL);
208 	if (!priv->tx_skbuff)
209 		goto free_rx_skbuff;
210 
211 	priv->skb_curtx = 0;
212 	priv->skb_dirtytx = 0;
213 	priv->curtx_bd = priv->tx_bd_base;
214 	priv->dirty_tx = priv->tx_bd_base;
215 	priv->currx_bd = priv->rx_bd_base;
216 	priv->currx_bdnum = 0;
217 
218 	/* init parameter base */
219 	cecr_subblock = ucc_fast_get_qe_cr_subblock(uf_info->ucc_num);
220 	ret = qe_issue_cmd(QE_ASSIGN_PAGE_TO_DEVICE, cecr_subblock,
221 			   QE_CR_PROTOCOL_UNSPECIFIED, priv->ucc_pram_offset);
222 
223 	priv->ucc_pram = (struct ucc_hdlc_param __iomem *)
224 					qe_muram_addr(priv->ucc_pram_offset);
225 
226 	/* Zero out parameter ram */
227 	memset_io(priv->ucc_pram, 0, sizeof(struct ucc_hdlc_param));
228 
229 	/* Alloc riptr, tiptr */
230 	riptr = qe_muram_alloc(32, 32);
231 	if (riptr < 0) {
232 		dev_err(priv->dev, "Cannot allocate MURAM mem for Receive internal temp data pointer\n");
233 		ret = -ENOMEM;
234 		goto free_tx_skbuff;
235 	}
236 
237 	tiptr = qe_muram_alloc(32, 32);
238 	if (tiptr < 0) {
239 		dev_err(priv->dev, "Cannot allocate MURAM mem for Transmit internal temp data pointer\n");
240 		ret = -ENOMEM;
241 		goto free_riptr;
242 	}
243 
244 	/* Set RIPTR, TIPTR */
245 	iowrite16be(riptr, &priv->ucc_pram->riptr);
246 	iowrite16be(tiptr, &priv->ucc_pram->tiptr);
247 
248 	/* Set MRBLR */
249 	iowrite16be(MAX_RX_BUF_LENGTH, &priv->ucc_pram->mrblr);
250 
251 	/* Set RBASE, TBASE */
252 	iowrite32be(priv->dma_rx_bd, &priv->ucc_pram->rbase);
253 	iowrite32be(priv->dma_tx_bd, &priv->ucc_pram->tbase);
254 
255 	/* Set RSTATE, TSTATE */
256 	iowrite32be(BMR_GBL | BMR_BIG_ENDIAN, &priv->ucc_pram->rstate);
257 	iowrite32be(BMR_GBL | BMR_BIG_ENDIAN, &priv->ucc_pram->tstate);
258 
259 	/* Set C_MASK, C_PRES for 16bit CRC */
260 	iowrite32be(CRC_16BIT_MASK, &priv->ucc_pram->c_mask);
261 	iowrite32be(CRC_16BIT_PRES, &priv->ucc_pram->c_pres);
262 
263 	iowrite16be(MAX_FRAME_LENGTH, &priv->ucc_pram->mflr);
264 	iowrite16be(DEFAULT_RFTHR, &priv->ucc_pram->rfthr);
265 	iowrite16be(DEFAULT_RFTHR, &priv->ucc_pram->rfcnt);
266 	iowrite16be(DEFAULT_ADDR_MASK, &priv->ucc_pram->hmask);
267 	iowrite16be(DEFAULT_HDLC_ADDR, &priv->ucc_pram->haddr1);
268 	iowrite16be(DEFAULT_HDLC_ADDR, &priv->ucc_pram->haddr2);
269 	iowrite16be(DEFAULT_HDLC_ADDR, &priv->ucc_pram->haddr3);
270 	iowrite16be(DEFAULT_HDLC_ADDR, &priv->ucc_pram->haddr4);
271 
272 	/* Get BD buffer */
273 	bd_buffer = dma_alloc_coherent(priv->dev,
274 				       (RX_BD_RING_LEN + TX_BD_RING_LEN) *
275 				       MAX_RX_BUF_LENGTH,
276 				       &bd_dma_addr, GFP_KERNEL);
277 
278 	if (!bd_buffer) {
279 		dev_err(priv->dev, "Could not allocate buffer descriptors\n");
280 		ret = -ENOMEM;
281 		goto free_tiptr;
282 	}
283 
284 	memset(bd_buffer, 0, (RX_BD_RING_LEN + TX_BD_RING_LEN)
285 			* MAX_RX_BUF_LENGTH);
286 
287 	priv->rx_buffer = bd_buffer;
288 	priv->tx_buffer = bd_buffer + RX_BD_RING_LEN * MAX_RX_BUF_LENGTH;
289 
290 	priv->dma_rx_addr = bd_dma_addr;
291 	priv->dma_tx_addr = bd_dma_addr + RX_BD_RING_LEN * MAX_RX_BUF_LENGTH;
292 
293 	for (i = 0; i < RX_BD_RING_LEN; i++) {
294 		if (i < (RX_BD_RING_LEN - 1))
295 			bd_status = R_E_S | R_I_S;
296 		else
297 			bd_status = R_E_S | R_I_S | R_W_S;
298 
299 		iowrite16be(bd_status, &priv->rx_bd_base[i].status);
300 		iowrite32be(priv->dma_rx_addr + i * MAX_RX_BUF_LENGTH,
301 			    &priv->rx_bd_base[i].buf);
302 	}
303 
304 	for (i = 0; i < TX_BD_RING_LEN; i++) {
305 		if (i < (TX_BD_RING_LEN - 1))
306 			bd_status =  T_I_S | T_TC_S;
307 		else
308 			bd_status =  T_I_S | T_TC_S | T_W_S;
309 
310 		iowrite16be(bd_status, &priv->tx_bd_base[i].status);
311 		iowrite32be(priv->dma_tx_addr + i * MAX_RX_BUF_LENGTH,
312 			    &priv->tx_bd_base[i].buf);
313 	}
314 
315 	return 0;
316 
317 free_tiptr:
318 	qe_muram_free(tiptr);
319 free_riptr:
320 	qe_muram_free(riptr);
321 free_tx_skbuff:
322 	kfree(priv->tx_skbuff);
323 free_rx_skbuff:
324 	kfree(priv->rx_skbuff);
325 free_ucc_pram:
326 	qe_muram_free(priv->ucc_pram_offset);
327 free_tx_bd:
328 	dma_free_coherent(priv->dev,
329 			  TX_BD_RING_LEN * sizeof(struct qe_bd),
330 			  priv->tx_bd_base, priv->dma_tx_bd);
331 free_rx_bd:
332 	dma_free_coherent(priv->dev,
333 			  RX_BD_RING_LEN * sizeof(struct qe_bd),
334 			  priv->rx_bd_base, priv->dma_rx_bd);
335 free_uccf:
336 	ucc_fast_free(priv->uccf);
337 
338 	return ret;
339 }
340 
341 static netdev_tx_t ucc_hdlc_tx(struct sk_buff *skb, struct net_device *dev)
342 {
343 	hdlc_device *hdlc = dev_to_hdlc(dev);
344 	struct ucc_hdlc_private *priv = (struct ucc_hdlc_private *)hdlc->priv;
345 	struct qe_bd __iomem *bd;
346 	u16 bd_status;
347 	unsigned long flags;
348 	u16 *proto_head;
349 
350 	switch (dev->type) {
351 	case ARPHRD_RAWHDLC:
352 		if (skb_headroom(skb) < HDLC_HEAD_LEN) {
353 			dev->stats.tx_dropped++;
354 			dev_kfree_skb(skb);
355 			netdev_err(dev, "No enough space for hdlc head\n");
356 			return -ENOMEM;
357 		}
358 
359 		skb_push(skb, HDLC_HEAD_LEN);
360 
361 		proto_head = (u16 *)skb->data;
362 		*proto_head = htons(DEFAULT_HDLC_HEAD);
363 
364 		dev->stats.tx_bytes += skb->len;
365 		break;
366 
367 	case ARPHRD_PPP:
368 		proto_head = (u16 *)skb->data;
369 		if (*proto_head != htons(DEFAULT_PPP_HEAD)) {
370 			dev->stats.tx_dropped++;
371 			dev_kfree_skb(skb);
372 			netdev_err(dev, "Wrong ppp header\n");
373 			return -ENOMEM;
374 		}
375 
376 		dev->stats.tx_bytes += skb->len;
377 		break;
378 
379 	default:
380 		dev->stats.tx_dropped++;
381 		dev_kfree_skb(skb);
382 		return -ENOMEM;
383 	}
384 	spin_lock_irqsave(&priv->lock, flags);
385 
386 	/* Start from the next BD that should be filled */
387 	bd = priv->curtx_bd;
388 	bd_status = ioread16be(&bd->status);
389 	/* Save the skb pointer so we can free it later */
390 	priv->tx_skbuff[priv->skb_curtx] = skb;
391 
392 	/* Update the current skb pointer (wrapping if this was the last) */
393 	priv->skb_curtx =
394 	    (priv->skb_curtx + 1) & TX_RING_MOD_MASK(TX_BD_RING_LEN);
395 
396 	/* copy skb data to tx buffer for sdma processing */
397 	memcpy(priv->tx_buffer + (be32_to_cpu(bd->buf) - priv->dma_tx_addr),
398 	       skb->data, skb->len);
399 
400 	/* set bd status and length */
401 	bd_status = (bd_status & T_W_S) | T_R_S | T_I_S | T_L_S | T_TC_S;
402 
403 	iowrite16be(skb->len, &bd->length);
404 	iowrite16be(bd_status, &bd->status);
405 
406 	/* Move to next BD in the ring */
407 	if (!(bd_status & T_W_S))
408 		bd += 1;
409 	else
410 		bd = priv->tx_bd_base;
411 
412 	if (bd == priv->dirty_tx) {
413 		if (!netif_queue_stopped(dev))
414 			netif_stop_queue(dev);
415 	}
416 
417 	priv->curtx_bd = bd;
418 
419 	spin_unlock_irqrestore(&priv->lock, flags);
420 
421 	return NETDEV_TX_OK;
422 }
423 
424 static int hdlc_tx_done(struct ucc_hdlc_private *priv)
425 {
426 	/* Start from the next BD that should be filled */
427 	struct net_device *dev = priv->ndev;
428 	struct qe_bd *bd;		/* BD pointer */
429 	u16 bd_status;
430 
431 	bd = priv->dirty_tx;
432 	bd_status = ioread16be(&bd->status);
433 
434 	/* Normal processing. */
435 	while ((bd_status & T_R_S) == 0) {
436 		struct sk_buff *skb;
437 
438 		/* BD contains already transmitted buffer.   */
439 		/* Handle the transmitted buffer and release */
440 		/* the BD to be used with the current frame  */
441 
442 		skb = priv->tx_skbuff[priv->skb_dirtytx];
443 		if (!skb)
444 			break;
445 		dev->stats.tx_packets++;
446 		memset(priv->tx_buffer +
447 		       (be32_to_cpu(bd->buf) - priv->dma_tx_addr),
448 		       0, skb->len);
449 		dev_kfree_skb_irq(skb);
450 
451 		priv->tx_skbuff[priv->skb_dirtytx] = NULL;
452 		priv->skb_dirtytx =
453 		    (priv->skb_dirtytx +
454 		     1) & TX_RING_MOD_MASK(TX_BD_RING_LEN);
455 
456 		/* We freed a buffer, so now we can restart transmission */
457 		if (netif_queue_stopped(dev))
458 			netif_wake_queue(dev);
459 
460 		/* Advance the confirmation BD pointer */
461 		if (!(bd_status & T_W_S))
462 			bd += 1;
463 		else
464 			bd = priv->tx_bd_base;
465 		bd_status = ioread16be(&bd->status);
466 	}
467 	priv->dirty_tx = bd;
468 
469 	return 0;
470 }
471 
472 static int hdlc_rx_done(struct ucc_hdlc_private *priv, int rx_work_limit)
473 {
474 	struct net_device *dev = priv->ndev;
475 	struct sk_buff *skb = NULL;
476 	hdlc_device *hdlc = dev_to_hdlc(dev);
477 	struct qe_bd *bd;
478 	u16 bd_status;
479 	u16 length, howmany = 0;
480 	u8 *bdbuffer;
481 
482 	bd = priv->currx_bd;
483 	bd_status = ioread16be(&bd->status);
484 
485 	/* while there are received buffers and BD is full (~R_E) */
486 	while (!((bd_status & (R_E_S)) || (--rx_work_limit < 0))) {
487 		if (bd_status & R_OV_S)
488 			dev->stats.rx_over_errors++;
489 		if (bd_status & R_CR_S) {
490 			dev->stats.rx_crc_errors++;
491 			dev->stats.rx_dropped++;
492 			goto recycle;
493 		}
494 		bdbuffer = priv->rx_buffer +
495 			(priv->currx_bdnum * MAX_RX_BUF_LENGTH);
496 		length = ioread16be(&bd->length);
497 
498 		switch (dev->type) {
499 		case ARPHRD_RAWHDLC:
500 			bdbuffer += HDLC_HEAD_LEN;
501 			length -= (HDLC_HEAD_LEN + HDLC_CRC_SIZE);
502 
503 			skb = dev_alloc_skb(length);
504 			if (!skb) {
505 				dev->stats.rx_dropped++;
506 				return -ENOMEM;
507 			}
508 
509 			skb_put(skb, length);
510 			skb->len = length;
511 			skb->dev = dev;
512 			memcpy(skb->data, bdbuffer, length);
513 			break;
514 
515 		case ARPHRD_PPP:
516 			length -= HDLC_CRC_SIZE;
517 
518 			skb = dev_alloc_skb(length);
519 			if (!skb) {
520 				dev->stats.rx_dropped++;
521 				return -ENOMEM;
522 			}
523 
524 			skb_put(skb, length);
525 			skb->len = length;
526 			skb->dev = dev;
527 			memcpy(skb->data, bdbuffer, length);
528 			break;
529 		}
530 
531 		dev->stats.rx_packets++;
532 		dev->stats.rx_bytes += skb->len;
533 		howmany++;
534 		if (hdlc->proto)
535 			skb->protocol = hdlc_type_trans(skb, dev);
536 		netif_receive_skb(skb);
537 
538 recycle:
539 		iowrite16be(bd_status | R_E_S | R_I_S, &bd->status);
540 
541 		/* update to point at the next bd */
542 		if (bd_status & R_W_S) {
543 			priv->currx_bdnum = 0;
544 			bd = priv->rx_bd_base;
545 		} else {
546 			if (priv->currx_bdnum < (RX_BD_RING_LEN - 1))
547 				priv->currx_bdnum += 1;
548 			else
549 				priv->currx_bdnum = RX_BD_RING_LEN - 1;
550 
551 			bd += 1;
552 		}
553 
554 		bd_status = ioread16be(&bd->status);
555 	}
556 
557 	priv->currx_bd = bd;
558 	return howmany;
559 }
560 
561 static int ucc_hdlc_poll(struct napi_struct *napi, int budget)
562 {
563 	struct ucc_hdlc_private *priv = container_of(napi,
564 						     struct ucc_hdlc_private,
565 						     napi);
566 	int howmany;
567 
568 	/* Tx event processing */
569 	spin_lock(&priv->lock);
570 	hdlc_tx_done(priv);
571 	spin_unlock(&priv->lock);
572 
573 	howmany = 0;
574 	howmany += hdlc_rx_done(priv, budget - howmany);
575 
576 	if (howmany < budget) {
577 		napi_complete_done(napi, howmany);
578 		qe_setbits32(priv->uccf->p_uccm,
579 			     (UCCE_HDLC_RX_EVENTS | UCCE_HDLC_TX_EVENTS) << 16);
580 	}
581 
582 	return howmany;
583 }
584 
585 static irqreturn_t ucc_hdlc_irq_handler(int irq, void *dev_id)
586 {
587 	struct ucc_hdlc_private *priv = (struct ucc_hdlc_private *)dev_id;
588 	struct net_device *dev = priv->ndev;
589 	struct ucc_fast_private *uccf;
590 	struct ucc_tdm_info *ut_info;
591 	u32 ucce;
592 	u32 uccm;
593 
594 	ut_info = priv->ut_info;
595 	uccf = priv->uccf;
596 
597 	ucce = ioread32be(uccf->p_ucce);
598 	uccm = ioread32be(uccf->p_uccm);
599 	ucce &= uccm;
600 	iowrite32be(ucce, uccf->p_ucce);
601 	if (!ucce)
602 		return IRQ_NONE;
603 
604 	if ((ucce >> 16) & (UCCE_HDLC_RX_EVENTS | UCCE_HDLC_TX_EVENTS)) {
605 		if (napi_schedule_prep(&priv->napi)) {
606 			uccm &= ~((UCCE_HDLC_RX_EVENTS | UCCE_HDLC_TX_EVENTS)
607 				  << 16);
608 			iowrite32be(uccm, uccf->p_uccm);
609 			__napi_schedule(&priv->napi);
610 		}
611 	}
612 
613 	/* Errors and other events */
614 	if (ucce >> 16 & UCC_HDLC_UCCE_BSY)
615 		dev->stats.rx_errors++;
616 	if (ucce >> 16 & UCC_HDLC_UCCE_TXE)
617 		dev->stats.tx_errors++;
618 
619 	return IRQ_HANDLED;
620 }
621 
622 static int uhdlc_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
623 {
624 	const size_t size = sizeof(te1_settings);
625 	te1_settings line;
626 	struct ucc_hdlc_private *priv = netdev_priv(dev);
627 
628 	if (cmd != SIOCWANDEV)
629 		return hdlc_ioctl(dev, ifr, cmd);
630 
631 	switch (ifr->ifr_settings.type) {
632 	case IF_GET_IFACE:
633 		ifr->ifr_settings.type = IF_IFACE_E1;
634 		if (ifr->ifr_settings.size < size) {
635 			ifr->ifr_settings.size = size; /* data size wanted */
636 			return -ENOBUFS;
637 		}
638 		memset(&line, 0, sizeof(line));
639 		line.clock_type = priv->clocking;
640 
641 		if (copy_to_user(ifr->ifr_settings.ifs_ifsu.sync, &line, size))
642 			return -EFAULT;
643 		return 0;
644 
645 	default:
646 		return hdlc_ioctl(dev, ifr, cmd);
647 	}
648 }
649 
650 static int uhdlc_open(struct net_device *dev)
651 {
652 	u32 cecr_subblock;
653 	hdlc_device *hdlc = dev_to_hdlc(dev);
654 	struct ucc_hdlc_private *priv = hdlc->priv;
655 	struct ucc_tdm *utdm = priv->utdm;
656 
657 	if (priv->hdlc_busy != 1) {
658 		if (request_irq(priv->ut_info->uf_info.irq,
659 				ucc_hdlc_irq_handler, 0, "hdlc", priv))
660 			return -ENODEV;
661 
662 		cecr_subblock = ucc_fast_get_qe_cr_subblock(
663 					priv->ut_info->uf_info.ucc_num);
664 
665 		qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
666 			     QE_CR_PROTOCOL_UNSPECIFIED, 0);
667 
668 		ucc_fast_enable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
669 
670 		/* Enable the TDM port */
671 		if (priv->tsa)
672 			utdm->si_regs->siglmr1_h |= (0x1 << utdm->tdm_port);
673 
674 		priv->hdlc_busy = 1;
675 		netif_device_attach(priv->ndev);
676 		napi_enable(&priv->napi);
677 		netif_start_queue(dev);
678 		hdlc_open(dev);
679 	}
680 
681 	return 0;
682 }
683 
684 static void uhdlc_memclean(struct ucc_hdlc_private *priv)
685 {
686 	qe_muram_free(priv->ucc_pram->riptr);
687 	qe_muram_free(priv->ucc_pram->tiptr);
688 
689 	if (priv->rx_bd_base) {
690 		dma_free_coherent(priv->dev,
691 				  RX_BD_RING_LEN * sizeof(struct qe_bd),
692 				  priv->rx_bd_base, priv->dma_rx_bd);
693 
694 		priv->rx_bd_base = NULL;
695 		priv->dma_rx_bd = 0;
696 	}
697 
698 	if (priv->tx_bd_base) {
699 		dma_free_coherent(priv->dev,
700 				  TX_BD_RING_LEN * sizeof(struct qe_bd),
701 				  priv->tx_bd_base, priv->dma_tx_bd);
702 
703 		priv->tx_bd_base = NULL;
704 		priv->dma_tx_bd = 0;
705 	}
706 
707 	if (priv->ucc_pram) {
708 		qe_muram_free(priv->ucc_pram_offset);
709 		priv->ucc_pram = NULL;
710 		priv->ucc_pram_offset = 0;
711 	 }
712 
713 	kfree(priv->rx_skbuff);
714 	priv->rx_skbuff = NULL;
715 
716 	kfree(priv->tx_skbuff);
717 	priv->tx_skbuff = NULL;
718 
719 	if (priv->uf_regs) {
720 		iounmap(priv->uf_regs);
721 		priv->uf_regs = NULL;
722 	}
723 
724 	if (priv->uccf) {
725 		ucc_fast_free(priv->uccf);
726 		priv->uccf = NULL;
727 	}
728 
729 	if (priv->rx_buffer) {
730 		dma_free_coherent(priv->dev,
731 				  RX_BD_RING_LEN * MAX_RX_BUF_LENGTH,
732 				  priv->rx_buffer, priv->dma_rx_addr);
733 		priv->rx_buffer = NULL;
734 		priv->dma_rx_addr = 0;
735 	}
736 
737 	if (priv->tx_buffer) {
738 		dma_free_coherent(priv->dev,
739 				  TX_BD_RING_LEN * MAX_RX_BUF_LENGTH,
740 				  priv->tx_buffer, priv->dma_tx_addr);
741 		priv->tx_buffer = NULL;
742 		priv->dma_tx_addr = 0;
743 	}
744 }
745 
746 static int uhdlc_close(struct net_device *dev)
747 {
748 	struct ucc_hdlc_private *priv = dev_to_hdlc(dev)->priv;
749 	struct ucc_tdm *utdm = priv->utdm;
750 	u32 cecr_subblock;
751 
752 	napi_disable(&priv->napi);
753 	cecr_subblock = ucc_fast_get_qe_cr_subblock(
754 				priv->ut_info->uf_info.ucc_num);
755 
756 	qe_issue_cmd(QE_GRACEFUL_STOP_TX, cecr_subblock,
757 		     (u8)QE_CR_PROTOCOL_UNSPECIFIED, 0);
758 	qe_issue_cmd(QE_CLOSE_RX_BD, cecr_subblock,
759 		     (u8)QE_CR_PROTOCOL_UNSPECIFIED, 0);
760 
761 	if (priv->tsa)
762 		utdm->si_regs->siglmr1_h &= ~(0x1 << utdm->tdm_port);
763 
764 	ucc_fast_disable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
765 
766 	free_irq(priv->ut_info->uf_info.irq, priv);
767 	netif_stop_queue(dev);
768 	priv->hdlc_busy = 0;
769 
770 	return 0;
771 }
772 
773 static int ucc_hdlc_attach(struct net_device *dev, unsigned short encoding,
774 			   unsigned short parity)
775 {
776 	struct ucc_hdlc_private *priv = dev_to_hdlc(dev)->priv;
777 
778 	if (encoding != ENCODING_NRZ &&
779 	    encoding != ENCODING_NRZI)
780 		return -EINVAL;
781 
782 	if (parity != PARITY_NONE &&
783 	    parity != PARITY_CRC32_PR1_CCITT &&
784 	    parity != PARITY_CRC16_PR1_CCITT)
785 		return -EINVAL;
786 
787 	priv->encoding = encoding;
788 	priv->parity = parity;
789 
790 	return 0;
791 }
792 
793 #ifdef CONFIG_PM
794 static void store_clk_config(struct ucc_hdlc_private *priv)
795 {
796 	struct qe_mux *qe_mux_reg = &qe_immr->qmx;
797 
798 	/* store si clk */
799 	priv->cmxsi1cr_h = ioread32be(&qe_mux_reg->cmxsi1cr_h);
800 	priv->cmxsi1cr_l = ioread32be(&qe_mux_reg->cmxsi1cr_l);
801 
802 	/* store si sync */
803 	priv->cmxsi1syr = ioread32be(&qe_mux_reg->cmxsi1syr);
804 
805 	/* store ucc clk */
806 	memcpy_fromio(priv->cmxucr, qe_mux_reg->cmxucr, 4 * sizeof(u32));
807 }
808 
809 static void resume_clk_config(struct ucc_hdlc_private *priv)
810 {
811 	struct qe_mux *qe_mux_reg = &qe_immr->qmx;
812 
813 	memcpy_toio(qe_mux_reg->cmxucr, priv->cmxucr, 4 * sizeof(u32));
814 
815 	iowrite32be(priv->cmxsi1cr_h, &qe_mux_reg->cmxsi1cr_h);
816 	iowrite32be(priv->cmxsi1cr_l, &qe_mux_reg->cmxsi1cr_l);
817 
818 	iowrite32be(priv->cmxsi1syr, &qe_mux_reg->cmxsi1syr);
819 }
820 
821 static int uhdlc_suspend(struct device *dev)
822 {
823 	struct ucc_hdlc_private *priv = dev_get_drvdata(dev);
824 	struct ucc_tdm_info *ut_info;
825 	struct ucc_fast __iomem *uf_regs;
826 
827 	if (!priv)
828 		return -EINVAL;
829 
830 	if (!netif_running(priv->ndev))
831 		return 0;
832 
833 	netif_device_detach(priv->ndev);
834 	napi_disable(&priv->napi);
835 
836 	ut_info = priv->ut_info;
837 	uf_regs = priv->uf_regs;
838 
839 	/* backup gumr guemr*/
840 	priv->gumr = ioread32be(&uf_regs->gumr);
841 	priv->guemr = ioread8(&uf_regs->guemr);
842 
843 	priv->ucc_pram_bak = kmalloc(sizeof(*priv->ucc_pram_bak),
844 					GFP_KERNEL);
845 	if (!priv->ucc_pram_bak)
846 		return -ENOMEM;
847 
848 	/* backup HDLC parameter */
849 	memcpy_fromio(priv->ucc_pram_bak, priv->ucc_pram,
850 		      sizeof(struct ucc_hdlc_param));
851 
852 	/* store the clk configuration */
853 	store_clk_config(priv);
854 
855 	/* save power */
856 	ucc_fast_disable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
857 
858 	return 0;
859 }
860 
861 static int uhdlc_resume(struct device *dev)
862 {
863 	struct ucc_hdlc_private *priv = dev_get_drvdata(dev);
864 	struct ucc_tdm *utdm;
865 	struct ucc_tdm_info *ut_info;
866 	struct ucc_fast __iomem *uf_regs;
867 	struct ucc_fast_private *uccf;
868 	struct ucc_fast_info *uf_info;
869 	int ret, i;
870 	u32 cecr_subblock;
871 	u16 bd_status;
872 
873 	if (!priv)
874 		return -EINVAL;
875 
876 	if (!netif_running(priv->ndev))
877 		return 0;
878 
879 	utdm = priv->utdm;
880 	ut_info = priv->ut_info;
881 	uf_info = &ut_info->uf_info;
882 	uf_regs = priv->uf_regs;
883 	uccf = priv->uccf;
884 
885 	/* restore gumr guemr */
886 	iowrite8(priv->guemr, &uf_regs->guemr);
887 	iowrite32be(priv->gumr, &uf_regs->gumr);
888 
889 	/* Set Virtual Fifo registers */
890 	iowrite16be(uf_info->urfs, &uf_regs->urfs);
891 	iowrite16be(uf_info->urfet, &uf_regs->urfet);
892 	iowrite16be(uf_info->urfset, &uf_regs->urfset);
893 	iowrite16be(uf_info->utfs, &uf_regs->utfs);
894 	iowrite16be(uf_info->utfet, &uf_regs->utfet);
895 	iowrite16be(uf_info->utftt, &uf_regs->utftt);
896 	/* utfb, urfb are offsets from MURAM base */
897 	iowrite32be(uccf->ucc_fast_tx_virtual_fifo_base_offset, &uf_regs->utfb);
898 	iowrite32be(uccf->ucc_fast_rx_virtual_fifo_base_offset, &uf_regs->urfb);
899 
900 	/* Rx Tx and sync clock routing */
901 	resume_clk_config(priv);
902 
903 	iowrite32be(uf_info->uccm_mask, &uf_regs->uccm);
904 	iowrite32be(0xffffffff, &uf_regs->ucce);
905 
906 	ucc_fast_disable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
907 
908 	/* rebuild SIRAM */
909 	if (priv->tsa)
910 		ucc_tdm_init(priv->utdm, priv->ut_info);
911 
912 	/* Write to QE CECR, UCCx channel to Stop Transmission */
913 	cecr_subblock = ucc_fast_get_qe_cr_subblock(uf_info->ucc_num);
914 	ret = qe_issue_cmd(QE_STOP_TX, cecr_subblock,
915 			   (u8)QE_CR_PROTOCOL_UNSPECIFIED, 0);
916 
917 	/* Set UPSMR normal mode */
918 	iowrite32be(0, &uf_regs->upsmr);
919 
920 	/* init parameter base */
921 	cecr_subblock = ucc_fast_get_qe_cr_subblock(uf_info->ucc_num);
922 	ret = qe_issue_cmd(QE_ASSIGN_PAGE_TO_DEVICE, cecr_subblock,
923 			   QE_CR_PROTOCOL_UNSPECIFIED, priv->ucc_pram_offset);
924 
925 	priv->ucc_pram = (struct ucc_hdlc_param __iomem *)
926 				qe_muram_addr(priv->ucc_pram_offset);
927 
928 	/* restore ucc parameter */
929 	memcpy_toio(priv->ucc_pram, priv->ucc_pram_bak,
930 		    sizeof(struct ucc_hdlc_param));
931 	kfree(priv->ucc_pram_bak);
932 
933 	/* rebuild BD entry */
934 	for (i = 0; i < RX_BD_RING_LEN; i++) {
935 		if (i < (RX_BD_RING_LEN - 1))
936 			bd_status = R_E_S | R_I_S;
937 		else
938 			bd_status = R_E_S | R_I_S | R_W_S;
939 
940 		iowrite16be(bd_status, &priv->rx_bd_base[i].status);
941 		iowrite32be(priv->dma_rx_addr + i * MAX_RX_BUF_LENGTH,
942 			    &priv->rx_bd_base[i].buf);
943 	}
944 
945 	for (i = 0; i < TX_BD_RING_LEN; i++) {
946 		if (i < (TX_BD_RING_LEN - 1))
947 			bd_status =  T_I_S | T_TC_S;
948 		else
949 			bd_status =  T_I_S | T_TC_S | T_W_S;
950 
951 		iowrite16be(bd_status, &priv->tx_bd_base[i].status);
952 		iowrite32be(priv->dma_tx_addr + i * MAX_RX_BUF_LENGTH,
953 			    &priv->tx_bd_base[i].buf);
954 	}
955 
956 	/* if hdlc is busy enable TX and RX */
957 	if (priv->hdlc_busy == 1) {
958 		cecr_subblock = ucc_fast_get_qe_cr_subblock(
959 					priv->ut_info->uf_info.ucc_num);
960 
961 		qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
962 			     (u8)QE_CR_PROTOCOL_UNSPECIFIED, 0);
963 
964 		ucc_fast_enable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
965 
966 		/* Enable the TDM port */
967 		if (priv->tsa)
968 			utdm->si_regs->siglmr1_h |= (0x1 << utdm->tdm_port);
969 	}
970 
971 	napi_enable(&priv->napi);
972 	netif_device_attach(priv->ndev);
973 
974 	return 0;
975 }
976 
977 static const struct dev_pm_ops uhdlc_pm_ops = {
978 	.suspend = uhdlc_suspend,
979 	.resume = uhdlc_resume,
980 	.freeze = uhdlc_suspend,
981 	.thaw = uhdlc_resume,
982 };
983 
984 #define HDLC_PM_OPS (&uhdlc_pm_ops)
985 
986 #else
987 
988 #define HDLC_PM_OPS NULL
989 
990 #endif
991 static const struct net_device_ops uhdlc_ops = {
992 	.ndo_open       = uhdlc_open,
993 	.ndo_stop       = uhdlc_close,
994 	.ndo_start_xmit = hdlc_start_xmit,
995 	.ndo_do_ioctl   = uhdlc_ioctl,
996 };
997 
998 static int ucc_hdlc_probe(struct platform_device *pdev)
999 {
1000 	struct device_node *np = pdev->dev.of_node;
1001 	struct ucc_hdlc_private *uhdlc_priv = NULL;
1002 	struct ucc_tdm_info *ut_info;
1003 	struct ucc_tdm *utdm = NULL;
1004 	struct resource res;
1005 	struct net_device *dev;
1006 	hdlc_device *hdlc;
1007 	int ucc_num;
1008 	const char *sprop;
1009 	int ret;
1010 	u32 val;
1011 
1012 	ret = of_property_read_u32_index(np, "cell-index", 0, &val);
1013 	if (ret) {
1014 		dev_err(&pdev->dev, "Invalid ucc property\n");
1015 		return -ENODEV;
1016 	}
1017 
1018 	ucc_num = val - 1;
1019 	if ((ucc_num > 3) || (ucc_num < 0)) {
1020 		dev_err(&pdev->dev, ": Invalid UCC num\n");
1021 		return -EINVAL;
1022 	}
1023 
1024 	memcpy(&utdm_info[ucc_num], &utdm_primary_info,
1025 	       sizeof(utdm_primary_info));
1026 
1027 	ut_info = &utdm_info[ucc_num];
1028 	ut_info->uf_info.ucc_num = ucc_num;
1029 
1030 	sprop = of_get_property(np, "rx-clock-name", NULL);
1031 	if (sprop) {
1032 		ut_info->uf_info.rx_clock = qe_clock_source(sprop);
1033 		if ((ut_info->uf_info.rx_clock < QE_CLK_NONE) ||
1034 		    (ut_info->uf_info.rx_clock > QE_CLK24)) {
1035 			dev_err(&pdev->dev, "Invalid rx-clock-name property\n");
1036 			return -EINVAL;
1037 		}
1038 	} else {
1039 		dev_err(&pdev->dev, "Invalid rx-clock-name property\n");
1040 		return -EINVAL;
1041 	}
1042 
1043 	sprop = of_get_property(np, "tx-clock-name", NULL);
1044 	if (sprop) {
1045 		ut_info->uf_info.tx_clock = qe_clock_source(sprop);
1046 		if ((ut_info->uf_info.tx_clock < QE_CLK_NONE) ||
1047 		    (ut_info->uf_info.tx_clock > QE_CLK24)) {
1048 			dev_err(&pdev->dev, "Invalid tx-clock-name property\n");
1049 			return -EINVAL;
1050 		}
1051 	} else {
1052 		dev_err(&pdev->dev, "Invalid tx-clock-name property\n");
1053 		return -EINVAL;
1054 	}
1055 
1056 	ret = of_address_to_resource(np, 0, &res);
1057 	if (ret)
1058 		return -EINVAL;
1059 
1060 	ut_info->uf_info.regs = res.start;
1061 	ut_info->uf_info.irq = irq_of_parse_and_map(np, 0);
1062 
1063 	uhdlc_priv = kzalloc(sizeof(*uhdlc_priv), GFP_KERNEL);
1064 	if (!uhdlc_priv) {
1065 		return -ENOMEM;
1066 	}
1067 
1068 	dev_set_drvdata(&pdev->dev, uhdlc_priv);
1069 	uhdlc_priv->dev = &pdev->dev;
1070 	uhdlc_priv->ut_info = ut_info;
1071 
1072 	if (of_get_property(np, "fsl,tdm-interface", NULL))
1073 		uhdlc_priv->tsa = 1;
1074 
1075 	if (of_get_property(np, "fsl,ucc-internal-loopback", NULL))
1076 		uhdlc_priv->loopback = 1;
1077 
1078 	if (of_get_property(np, "fsl,hdlc-bus", NULL))
1079 		uhdlc_priv->hdlc_bus = 1;
1080 
1081 	if (uhdlc_priv->tsa == 1) {
1082 		utdm = kzalloc(sizeof(*utdm), GFP_KERNEL);
1083 		if (!utdm) {
1084 			ret = -ENOMEM;
1085 			dev_err(&pdev->dev, "No mem to alloc ucc tdm data\n");
1086 			goto free_uhdlc_priv;
1087 		}
1088 		uhdlc_priv->utdm = utdm;
1089 		ret = ucc_of_parse_tdm(np, utdm, ut_info);
1090 		if (ret)
1091 			goto free_utdm;
1092 	}
1093 
1094 	ret = uhdlc_init(uhdlc_priv);
1095 	if (ret) {
1096 		dev_err(&pdev->dev, "Failed to init uhdlc\n");
1097 		goto free_utdm;
1098 	}
1099 
1100 	dev = alloc_hdlcdev(uhdlc_priv);
1101 	if (!dev) {
1102 		ret = -ENOMEM;
1103 		pr_err("ucc_hdlc: unable to allocate memory\n");
1104 		goto undo_uhdlc_init;
1105 	}
1106 
1107 	uhdlc_priv->ndev = dev;
1108 	hdlc = dev_to_hdlc(dev);
1109 	dev->tx_queue_len = 16;
1110 	dev->netdev_ops = &uhdlc_ops;
1111 	hdlc->attach = ucc_hdlc_attach;
1112 	hdlc->xmit = ucc_hdlc_tx;
1113 	netif_napi_add(dev, &uhdlc_priv->napi, ucc_hdlc_poll, 32);
1114 	if (register_hdlc_device(dev)) {
1115 		ret = -ENOBUFS;
1116 		pr_err("ucc_hdlc: unable to register hdlc device\n");
1117 		free_netdev(dev);
1118 		goto free_dev;
1119 	}
1120 
1121 	return 0;
1122 
1123 free_dev:
1124 	free_netdev(dev);
1125 undo_uhdlc_init:
1126 free_utdm:
1127 	if (uhdlc_priv->tsa)
1128 		kfree(utdm);
1129 free_uhdlc_priv:
1130 	kfree(uhdlc_priv);
1131 	return ret;
1132 }
1133 
1134 static int ucc_hdlc_remove(struct platform_device *pdev)
1135 {
1136 	struct ucc_hdlc_private *priv = dev_get_drvdata(&pdev->dev);
1137 
1138 	uhdlc_memclean(priv);
1139 
1140 	if (priv->utdm->si_regs) {
1141 		iounmap(priv->utdm->si_regs);
1142 		priv->utdm->si_regs = NULL;
1143 	}
1144 
1145 	if (priv->utdm->siram) {
1146 		iounmap(priv->utdm->siram);
1147 		priv->utdm->siram = NULL;
1148 	}
1149 	kfree(priv);
1150 
1151 	dev_info(&pdev->dev, "UCC based hdlc module removed\n");
1152 
1153 	return 0;
1154 }
1155 
1156 static const struct of_device_id fsl_ucc_hdlc_of_match[] = {
1157 	{
1158 	.compatible = "fsl,ucc-hdlc",
1159 	},
1160 	{},
1161 };
1162 
1163 MODULE_DEVICE_TABLE(of, fsl_ucc_hdlc_of_match);
1164 
1165 static struct platform_driver ucc_hdlc_driver = {
1166 	.probe	= ucc_hdlc_probe,
1167 	.remove	= ucc_hdlc_remove,
1168 	.driver	= {
1169 		.name		= DRV_NAME,
1170 		.pm		= HDLC_PM_OPS,
1171 		.of_match_table	= fsl_ucc_hdlc_of_match,
1172 	},
1173 };
1174 
1175 module_platform_driver(ucc_hdlc_driver);
1176 MODULE_LICENSE("GPL");
1177