xref: /openbmc/linux/drivers/net/wan/fsl_ucc_hdlc.c (revision 85250a24)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /* Freescale QUICC Engine HDLC Device Driver
3  *
4  * Copyright 2016 Freescale Semiconductor Inc.
5  */
6 
7 #include <linux/delay.h>
8 #include <linux/dma-mapping.h>
9 #include <linux/hdlc.h>
10 #include <linux/init.h>
11 #include <linux/interrupt.h>
12 #include <linux/io.h>
13 #include <linux/irq.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/netdevice.h>
17 #include <linux/of_address.h>
18 #include <linux/of_irq.h>
19 #include <linux/of_platform.h>
20 #include <linux/platform_device.h>
21 #include <linux/sched.h>
22 #include <linux/skbuff.h>
23 #include <linux/slab.h>
24 #include <linux/spinlock.h>
25 #include <linux/stddef.h>
26 #include <soc/fsl/qe/qe_tdm.h>
27 #include <uapi/linux/if_arp.h>
28 
29 #include "fsl_ucc_hdlc.h"
30 
31 #define DRV_DESC "Freescale QE UCC HDLC Driver"
32 #define DRV_NAME "ucc_hdlc"
33 
34 #define TDM_PPPOHT_SLIC_MAXIN
35 #define RX_BD_ERRORS (R_CD_S | R_OV_S | R_CR_S | R_AB_S | R_NO_S | R_LG_S)
36 
37 static struct ucc_tdm_info utdm_primary_info = {
38 	.uf_info = {
39 		.tsa = 0,
40 		.cdp = 0,
41 		.cds = 1,
42 		.ctsp = 1,
43 		.ctss = 1,
44 		.revd = 0,
45 		.urfs = 256,
46 		.utfs = 256,
47 		.urfet = 128,
48 		.urfset = 192,
49 		.utfet = 128,
50 		.utftt = 0x40,
51 		.ufpt = 256,
52 		.mode = UCC_FAST_PROTOCOL_MODE_HDLC,
53 		.ttx_trx = UCC_FAST_GUMR_TRANSPARENT_TTX_TRX_NORMAL,
54 		.tenc = UCC_FAST_TX_ENCODING_NRZ,
55 		.renc = UCC_FAST_RX_ENCODING_NRZ,
56 		.tcrc = UCC_FAST_16_BIT_CRC,
57 		.synl = UCC_FAST_SYNC_LEN_NOT_USED,
58 	},
59 
60 	.si_info = {
61 #ifdef TDM_PPPOHT_SLIC_MAXIN
62 		.simr_rfsd = 1,
63 		.simr_tfsd = 2,
64 #else
65 		.simr_rfsd = 0,
66 		.simr_tfsd = 0,
67 #endif
68 		.simr_crt = 0,
69 		.simr_sl = 0,
70 		.simr_ce = 1,
71 		.simr_fe = 1,
72 		.simr_gm = 0,
73 	},
74 };
75 
76 static struct ucc_tdm_info utdm_info[UCC_MAX_NUM];
77 
78 static int uhdlc_init(struct ucc_hdlc_private *priv)
79 {
80 	struct ucc_tdm_info *ut_info;
81 	struct ucc_fast_info *uf_info;
82 	u32 cecr_subblock;
83 	u16 bd_status;
84 	int ret, i;
85 	void *bd_buffer;
86 	dma_addr_t bd_dma_addr;
87 	s32 riptr;
88 	s32 tiptr;
89 	u32 gumr;
90 
91 	ut_info = priv->ut_info;
92 	uf_info = &ut_info->uf_info;
93 
94 	if (priv->tsa) {
95 		uf_info->tsa = 1;
96 		uf_info->ctsp = 1;
97 		uf_info->cds = 1;
98 		uf_info->ctss = 1;
99 	} else {
100 		uf_info->cds = 0;
101 		uf_info->ctsp = 0;
102 		uf_info->ctss = 0;
103 	}
104 
105 	/* This sets HPM register in CMXUCR register which configures a
106 	 * open drain connected HDLC bus
107 	 */
108 	if (priv->hdlc_bus)
109 		uf_info->brkpt_support = 1;
110 
111 	uf_info->uccm_mask = ((UCC_HDLC_UCCE_RXB | UCC_HDLC_UCCE_RXF |
112 				UCC_HDLC_UCCE_TXB) << 16);
113 
114 	ret = ucc_fast_init(uf_info, &priv->uccf);
115 	if (ret) {
116 		dev_err(priv->dev, "Failed to init uccf.");
117 		return ret;
118 	}
119 
120 	priv->uf_regs = priv->uccf->uf_regs;
121 	ucc_fast_disable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
122 
123 	/* Loopback mode */
124 	if (priv->loopback) {
125 		dev_info(priv->dev, "Loopback Mode\n");
126 		/* use the same clock when work in loopback */
127 		qe_setbrg(ut_info->uf_info.rx_clock, 20000000, 1);
128 
129 		gumr = ioread32be(&priv->uf_regs->gumr);
130 		gumr |= (UCC_FAST_GUMR_LOOPBACK | UCC_FAST_GUMR_CDS |
131 			 UCC_FAST_GUMR_TCI);
132 		gumr &= ~(UCC_FAST_GUMR_CTSP | UCC_FAST_GUMR_RSYN);
133 		iowrite32be(gumr, &priv->uf_regs->gumr);
134 	}
135 
136 	/* Initialize SI */
137 	if (priv->tsa)
138 		ucc_tdm_init(priv->utdm, priv->ut_info);
139 
140 	/* Write to QE CECR, UCCx channel to Stop Transmission */
141 	cecr_subblock = ucc_fast_get_qe_cr_subblock(uf_info->ucc_num);
142 	ret = qe_issue_cmd(QE_STOP_TX, cecr_subblock,
143 			   QE_CR_PROTOCOL_UNSPECIFIED, 0);
144 
145 	/* Set UPSMR normal mode (need fixed)*/
146 	iowrite32be(0, &priv->uf_regs->upsmr);
147 
148 	/* hdlc_bus mode */
149 	if (priv->hdlc_bus) {
150 		u32 upsmr;
151 
152 		dev_info(priv->dev, "HDLC bus Mode\n");
153 		upsmr = ioread32be(&priv->uf_regs->upsmr);
154 
155 		/* bus mode and retransmit enable, with collision window
156 		 * set to 8 bytes
157 		 */
158 		upsmr |= UCC_HDLC_UPSMR_RTE | UCC_HDLC_UPSMR_BUS |
159 				UCC_HDLC_UPSMR_CW8;
160 		iowrite32be(upsmr, &priv->uf_regs->upsmr);
161 
162 		/* explicitly disable CDS & CTSP */
163 		gumr = ioread32be(&priv->uf_regs->gumr);
164 		gumr &= ~(UCC_FAST_GUMR_CDS | UCC_FAST_GUMR_CTSP);
165 		/* set automatic sync to explicitly ignore CD signal */
166 		gumr |= UCC_FAST_GUMR_SYNL_AUTO;
167 		iowrite32be(gumr, &priv->uf_regs->gumr);
168 	}
169 
170 	priv->rx_ring_size = RX_BD_RING_LEN;
171 	priv->tx_ring_size = TX_BD_RING_LEN;
172 	/* Alloc Rx BD */
173 	priv->rx_bd_base = dma_alloc_coherent(priv->dev,
174 			RX_BD_RING_LEN * sizeof(struct qe_bd),
175 			&priv->dma_rx_bd, GFP_KERNEL);
176 
177 	if (!priv->rx_bd_base) {
178 		dev_err(priv->dev, "Cannot allocate MURAM memory for RxBDs\n");
179 		ret = -ENOMEM;
180 		goto free_uccf;
181 	}
182 
183 	/* Alloc Tx BD */
184 	priv->tx_bd_base = dma_alloc_coherent(priv->dev,
185 			TX_BD_RING_LEN * sizeof(struct qe_bd),
186 			&priv->dma_tx_bd, GFP_KERNEL);
187 
188 	if (!priv->tx_bd_base) {
189 		dev_err(priv->dev, "Cannot allocate MURAM memory for TxBDs\n");
190 		ret = -ENOMEM;
191 		goto free_rx_bd;
192 	}
193 
194 	/* Alloc parameter ram for ucc hdlc */
195 	priv->ucc_pram_offset = qe_muram_alloc(sizeof(struct ucc_hdlc_param),
196 				ALIGNMENT_OF_UCC_HDLC_PRAM);
197 
198 	if (priv->ucc_pram_offset < 0) {
199 		dev_err(priv->dev, "Can not allocate MURAM for hdlc parameter.\n");
200 		ret = -ENOMEM;
201 		goto free_tx_bd;
202 	}
203 
204 	priv->rx_skbuff = kcalloc(priv->rx_ring_size,
205 				  sizeof(*priv->rx_skbuff),
206 				  GFP_KERNEL);
207 	if (!priv->rx_skbuff) {
208 		ret = -ENOMEM;
209 		goto free_ucc_pram;
210 	}
211 
212 	priv->tx_skbuff = kcalloc(priv->tx_ring_size,
213 				  sizeof(*priv->tx_skbuff),
214 				  GFP_KERNEL);
215 	if (!priv->tx_skbuff) {
216 		ret = -ENOMEM;
217 		goto free_rx_skbuff;
218 	}
219 
220 	priv->skb_curtx = 0;
221 	priv->skb_dirtytx = 0;
222 	priv->curtx_bd = priv->tx_bd_base;
223 	priv->dirty_tx = priv->tx_bd_base;
224 	priv->currx_bd = priv->rx_bd_base;
225 	priv->currx_bdnum = 0;
226 
227 	/* init parameter base */
228 	cecr_subblock = ucc_fast_get_qe_cr_subblock(uf_info->ucc_num);
229 	ret = qe_issue_cmd(QE_ASSIGN_PAGE_TO_DEVICE, cecr_subblock,
230 			   QE_CR_PROTOCOL_UNSPECIFIED, priv->ucc_pram_offset);
231 
232 	priv->ucc_pram = (struct ucc_hdlc_param __iomem *)
233 					qe_muram_addr(priv->ucc_pram_offset);
234 
235 	/* Zero out parameter ram */
236 	memset_io(priv->ucc_pram, 0, sizeof(struct ucc_hdlc_param));
237 
238 	/* Alloc riptr, tiptr */
239 	riptr = qe_muram_alloc(32, 32);
240 	if (riptr < 0) {
241 		dev_err(priv->dev, "Cannot allocate MURAM mem for Receive internal temp data pointer\n");
242 		ret = -ENOMEM;
243 		goto free_tx_skbuff;
244 	}
245 
246 	tiptr = qe_muram_alloc(32, 32);
247 	if (tiptr < 0) {
248 		dev_err(priv->dev, "Cannot allocate MURAM mem for Transmit internal temp data pointer\n");
249 		ret = -ENOMEM;
250 		goto free_riptr;
251 	}
252 	if (riptr != (u16)riptr || tiptr != (u16)tiptr) {
253 		dev_err(priv->dev, "MURAM allocation out of addressable range\n");
254 		ret = -ENOMEM;
255 		goto free_tiptr;
256 	}
257 
258 	/* Set RIPTR, TIPTR */
259 	iowrite16be(riptr, &priv->ucc_pram->riptr);
260 	iowrite16be(tiptr, &priv->ucc_pram->tiptr);
261 
262 	/* Set MRBLR */
263 	iowrite16be(MAX_RX_BUF_LENGTH, &priv->ucc_pram->mrblr);
264 
265 	/* Set RBASE, TBASE */
266 	iowrite32be(priv->dma_rx_bd, &priv->ucc_pram->rbase);
267 	iowrite32be(priv->dma_tx_bd, &priv->ucc_pram->tbase);
268 
269 	/* Set RSTATE, TSTATE */
270 	iowrite32be(BMR_GBL | BMR_BIG_ENDIAN, &priv->ucc_pram->rstate);
271 	iowrite32be(BMR_GBL | BMR_BIG_ENDIAN, &priv->ucc_pram->tstate);
272 
273 	/* Set C_MASK, C_PRES for 16bit CRC */
274 	iowrite32be(CRC_16BIT_MASK, &priv->ucc_pram->c_mask);
275 	iowrite32be(CRC_16BIT_PRES, &priv->ucc_pram->c_pres);
276 
277 	iowrite16be(MAX_FRAME_LENGTH, &priv->ucc_pram->mflr);
278 	iowrite16be(DEFAULT_RFTHR, &priv->ucc_pram->rfthr);
279 	iowrite16be(DEFAULT_RFTHR, &priv->ucc_pram->rfcnt);
280 	iowrite16be(priv->hmask, &priv->ucc_pram->hmask);
281 	iowrite16be(DEFAULT_HDLC_ADDR, &priv->ucc_pram->haddr1);
282 	iowrite16be(DEFAULT_HDLC_ADDR, &priv->ucc_pram->haddr2);
283 	iowrite16be(DEFAULT_HDLC_ADDR, &priv->ucc_pram->haddr3);
284 	iowrite16be(DEFAULT_HDLC_ADDR, &priv->ucc_pram->haddr4);
285 
286 	/* Get BD buffer */
287 	bd_buffer = dma_alloc_coherent(priv->dev,
288 				       (RX_BD_RING_LEN + TX_BD_RING_LEN) * MAX_RX_BUF_LENGTH,
289 				       &bd_dma_addr, GFP_KERNEL);
290 
291 	if (!bd_buffer) {
292 		dev_err(priv->dev, "Could not allocate buffer descriptors\n");
293 		ret = -ENOMEM;
294 		goto free_tiptr;
295 	}
296 
297 	priv->rx_buffer = bd_buffer;
298 	priv->tx_buffer = bd_buffer + RX_BD_RING_LEN * MAX_RX_BUF_LENGTH;
299 
300 	priv->dma_rx_addr = bd_dma_addr;
301 	priv->dma_tx_addr = bd_dma_addr + RX_BD_RING_LEN * MAX_RX_BUF_LENGTH;
302 
303 	for (i = 0; i < RX_BD_RING_LEN; i++) {
304 		if (i < (RX_BD_RING_LEN - 1))
305 			bd_status = R_E_S | R_I_S;
306 		else
307 			bd_status = R_E_S | R_I_S | R_W_S;
308 
309 		priv->rx_bd_base[i].status = cpu_to_be16(bd_status);
310 		priv->rx_bd_base[i].buf = cpu_to_be32(priv->dma_rx_addr + i * MAX_RX_BUF_LENGTH);
311 	}
312 
313 	for (i = 0; i < TX_BD_RING_LEN; i++) {
314 		if (i < (TX_BD_RING_LEN - 1))
315 			bd_status =  T_I_S | T_TC_S;
316 		else
317 			bd_status =  T_I_S | T_TC_S | T_W_S;
318 
319 		priv->tx_bd_base[i].status = cpu_to_be16(bd_status);
320 		priv->tx_bd_base[i].buf = cpu_to_be32(priv->dma_tx_addr + i * MAX_RX_BUF_LENGTH);
321 	}
322 	dma_wmb();
323 
324 	return 0;
325 
326 free_tiptr:
327 	qe_muram_free(tiptr);
328 free_riptr:
329 	qe_muram_free(riptr);
330 free_tx_skbuff:
331 	kfree(priv->tx_skbuff);
332 free_rx_skbuff:
333 	kfree(priv->rx_skbuff);
334 free_ucc_pram:
335 	qe_muram_free(priv->ucc_pram_offset);
336 free_tx_bd:
337 	dma_free_coherent(priv->dev,
338 			  TX_BD_RING_LEN * sizeof(struct qe_bd),
339 			  priv->tx_bd_base, priv->dma_tx_bd);
340 free_rx_bd:
341 	dma_free_coherent(priv->dev,
342 			  RX_BD_RING_LEN * sizeof(struct qe_bd),
343 			  priv->rx_bd_base, priv->dma_rx_bd);
344 free_uccf:
345 	ucc_fast_free(priv->uccf);
346 
347 	return ret;
348 }
349 
350 static netdev_tx_t ucc_hdlc_tx(struct sk_buff *skb, struct net_device *dev)
351 {
352 	hdlc_device *hdlc = dev_to_hdlc(dev);
353 	struct ucc_hdlc_private *priv = (struct ucc_hdlc_private *)hdlc->priv;
354 	struct qe_bd *bd;
355 	u16 bd_status;
356 	unsigned long flags;
357 	__be16 *proto_head;
358 
359 	switch (dev->type) {
360 	case ARPHRD_RAWHDLC:
361 		if (skb_headroom(skb) < HDLC_HEAD_LEN) {
362 			dev->stats.tx_dropped++;
363 			dev_kfree_skb(skb);
364 			netdev_err(dev, "No enough space for hdlc head\n");
365 			return -ENOMEM;
366 		}
367 
368 		skb_push(skb, HDLC_HEAD_LEN);
369 
370 		proto_head = (__be16 *)skb->data;
371 		*proto_head = htons(DEFAULT_HDLC_HEAD);
372 
373 		dev->stats.tx_bytes += skb->len;
374 		break;
375 
376 	case ARPHRD_PPP:
377 		proto_head = (__be16 *)skb->data;
378 		if (*proto_head != htons(DEFAULT_PPP_HEAD)) {
379 			dev->stats.tx_dropped++;
380 			dev_kfree_skb(skb);
381 			netdev_err(dev, "Wrong ppp header\n");
382 			return -ENOMEM;
383 		}
384 
385 		dev->stats.tx_bytes += skb->len;
386 		break;
387 
388 	case ARPHRD_ETHER:
389 		dev->stats.tx_bytes += skb->len;
390 		break;
391 
392 	default:
393 		dev->stats.tx_dropped++;
394 		dev_kfree_skb(skb);
395 		return -ENOMEM;
396 	}
397 	netdev_sent_queue(dev, skb->len);
398 	spin_lock_irqsave(&priv->lock, flags);
399 
400 	dma_rmb();
401 	/* Start from the next BD that should be filled */
402 	bd = priv->curtx_bd;
403 	bd_status = be16_to_cpu(bd->status);
404 	/* Save the skb pointer so we can free it later */
405 	priv->tx_skbuff[priv->skb_curtx] = skb;
406 
407 	/* Update the current skb pointer (wrapping if this was the last) */
408 	priv->skb_curtx =
409 	    (priv->skb_curtx + 1) & TX_RING_MOD_MASK(TX_BD_RING_LEN);
410 
411 	/* copy skb data to tx buffer for sdma processing */
412 	memcpy(priv->tx_buffer + (be32_to_cpu(bd->buf) - priv->dma_tx_addr),
413 	       skb->data, skb->len);
414 
415 	/* set bd status and length */
416 	bd_status = (bd_status & T_W_S) | T_R_S | T_I_S | T_L_S | T_TC_S;
417 
418 	bd->length = cpu_to_be16(skb->len);
419 	bd->status = cpu_to_be16(bd_status);
420 
421 	/* Move to next BD in the ring */
422 	if (!(bd_status & T_W_S))
423 		bd += 1;
424 	else
425 		bd = priv->tx_bd_base;
426 
427 	if (bd == priv->dirty_tx) {
428 		if (!netif_queue_stopped(dev))
429 			netif_stop_queue(dev);
430 	}
431 
432 	priv->curtx_bd = bd;
433 
434 	spin_unlock_irqrestore(&priv->lock, flags);
435 
436 	return NETDEV_TX_OK;
437 }
438 
439 static int hdlc_tx_restart(struct ucc_hdlc_private *priv)
440 {
441 	u32 cecr_subblock;
442 
443 	cecr_subblock =
444 		ucc_fast_get_qe_cr_subblock(priv->ut_info->uf_info.ucc_num);
445 
446 	qe_issue_cmd(QE_RESTART_TX, cecr_subblock,
447 		     QE_CR_PROTOCOL_UNSPECIFIED, 0);
448 	return 0;
449 }
450 
451 static int hdlc_tx_done(struct ucc_hdlc_private *priv)
452 {
453 	/* Start from the next BD that should be filled */
454 	struct net_device *dev = priv->ndev;
455 	unsigned int bytes_sent = 0;
456 	int howmany = 0;
457 	struct qe_bd *bd;		/* BD pointer */
458 	u16 bd_status;
459 	int tx_restart = 0;
460 
461 	dma_rmb();
462 	bd = priv->dirty_tx;
463 	bd_status = be16_to_cpu(bd->status);
464 
465 	/* Normal processing. */
466 	while ((bd_status & T_R_S) == 0) {
467 		struct sk_buff *skb;
468 
469 		if (bd_status & T_UN_S) { /* Underrun */
470 			dev->stats.tx_fifo_errors++;
471 			tx_restart = 1;
472 		}
473 		if (bd_status & T_CT_S) { /* Carrier lost */
474 			dev->stats.tx_carrier_errors++;
475 			tx_restart = 1;
476 		}
477 
478 		/* BD contains already transmitted buffer.   */
479 		/* Handle the transmitted buffer and release */
480 		/* the BD to be used with the current frame  */
481 
482 		skb = priv->tx_skbuff[priv->skb_dirtytx];
483 		if (!skb)
484 			break;
485 		howmany++;
486 		bytes_sent += skb->len;
487 		dev->stats.tx_packets++;
488 		memset(priv->tx_buffer +
489 		       (be32_to_cpu(bd->buf) - priv->dma_tx_addr),
490 		       0, skb->len);
491 		dev_consume_skb_irq(skb);
492 
493 		priv->tx_skbuff[priv->skb_dirtytx] = NULL;
494 		priv->skb_dirtytx =
495 		    (priv->skb_dirtytx +
496 		     1) & TX_RING_MOD_MASK(TX_BD_RING_LEN);
497 
498 		/* We freed a buffer, so now we can restart transmission */
499 		if (netif_queue_stopped(dev))
500 			netif_wake_queue(dev);
501 
502 		/* Advance the confirmation BD pointer */
503 		if (!(bd_status & T_W_S))
504 			bd += 1;
505 		else
506 			bd = priv->tx_bd_base;
507 		bd_status = be16_to_cpu(bd->status);
508 	}
509 	priv->dirty_tx = bd;
510 
511 	if (tx_restart)
512 		hdlc_tx_restart(priv);
513 
514 	netdev_completed_queue(dev, howmany, bytes_sent);
515 	return 0;
516 }
517 
518 static int hdlc_rx_done(struct ucc_hdlc_private *priv, int rx_work_limit)
519 {
520 	struct net_device *dev = priv->ndev;
521 	struct sk_buff *skb = NULL;
522 	hdlc_device *hdlc = dev_to_hdlc(dev);
523 	struct qe_bd *bd;
524 	u16 bd_status;
525 	u16 length, howmany = 0;
526 	u8 *bdbuffer;
527 
528 	dma_rmb();
529 	bd = priv->currx_bd;
530 	bd_status = be16_to_cpu(bd->status);
531 
532 	/* while there are received buffers and BD is full (~R_E) */
533 	while (!((bd_status & (R_E_S)) || (--rx_work_limit < 0))) {
534 		if (bd_status & (RX_BD_ERRORS)) {
535 			dev->stats.rx_errors++;
536 
537 			if (bd_status & R_CD_S)
538 				dev->stats.collisions++;
539 			if (bd_status & R_OV_S)
540 				dev->stats.rx_fifo_errors++;
541 			if (bd_status & R_CR_S)
542 				dev->stats.rx_crc_errors++;
543 			if (bd_status & R_AB_S)
544 				dev->stats.rx_over_errors++;
545 			if (bd_status & R_NO_S)
546 				dev->stats.rx_frame_errors++;
547 			if (bd_status & R_LG_S)
548 				dev->stats.rx_length_errors++;
549 
550 			goto recycle;
551 		}
552 		bdbuffer = priv->rx_buffer +
553 			(priv->currx_bdnum * MAX_RX_BUF_LENGTH);
554 		length = be16_to_cpu(bd->length);
555 
556 		switch (dev->type) {
557 		case ARPHRD_RAWHDLC:
558 			bdbuffer += HDLC_HEAD_LEN;
559 			length -= (HDLC_HEAD_LEN + HDLC_CRC_SIZE);
560 
561 			skb = dev_alloc_skb(length);
562 			if (!skb) {
563 				dev->stats.rx_dropped++;
564 				return -ENOMEM;
565 			}
566 
567 			skb_put(skb, length);
568 			skb->len = length;
569 			skb->dev = dev;
570 			memcpy(skb->data, bdbuffer, length);
571 			break;
572 
573 		case ARPHRD_PPP:
574 		case ARPHRD_ETHER:
575 			length -= HDLC_CRC_SIZE;
576 
577 			skb = dev_alloc_skb(length);
578 			if (!skb) {
579 				dev->stats.rx_dropped++;
580 				return -ENOMEM;
581 			}
582 
583 			skb_put(skb, length);
584 			skb->len = length;
585 			skb->dev = dev;
586 			memcpy(skb->data, bdbuffer, length);
587 			break;
588 		}
589 
590 		dev->stats.rx_packets++;
591 		dev->stats.rx_bytes += skb->len;
592 		howmany++;
593 		if (hdlc->proto)
594 			skb->protocol = hdlc_type_trans(skb, dev);
595 		netif_receive_skb(skb);
596 
597 recycle:
598 		bd->status = cpu_to_be16((bd_status & R_W_S) | R_E_S | R_I_S);
599 
600 		/* update to point at the next bd */
601 		if (bd_status & R_W_S) {
602 			priv->currx_bdnum = 0;
603 			bd = priv->rx_bd_base;
604 		} else {
605 			if (priv->currx_bdnum < (RX_BD_RING_LEN - 1))
606 				priv->currx_bdnum += 1;
607 			else
608 				priv->currx_bdnum = RX_BD_RING_LEN - 1;
609 
610 			bd += 1;
611 		}
612 
613 		bd_status = be16_to_cpu(bd->status);
614 	}
615 	dma_rmb();
616 
617 	priv->currx_bd = bd;
618 	return howmany;
619 }
620 
621 static int ucc_hdlc_poll(struct napi_struct *napi, int budget)
622 {
623 	struct ucc_hdlc_private *priv = container_of(napi,
624 						     struct ucc_hdlc_private,
625 						     napi);
626 	int howmany;
627 
628 	/* Tx event processing */
629 	spin_lock(&priv->lock);
630 	hdlc_tx_done(priv);
631 	spin_unlock(&priv->lock);
632 
633 	howmany = 0;
634 	howmany += hdlc_rx_done(priv, budget - howmany);
635 
636 	if (howmany < budget) {
637 		napi_complete_done(napi, howmany);
638 		qe_setbits_be32(priv->uccf->p_uccm,
639 				(UCCE_HDLC_RX_EVENTS | UCCE_HDLC_TX_EVENTS) << 16);
640 	}
641 
642 	return howmany;
643 }
644 
645 static irqreturn_t ucc_hdlc_irq_handler(int irq, void *dev_id)
646 {
647 	struct ucc_hdlc_private *priv = (struct ucc_hdlc_private *)dev_id;
648 	struct net_device *dev = priv->ndev;
649 	struct ucc_fast_private *uccf;
650 	u32 ucce;
651 	u32 uccm;
652 
653 	uccf = priv->uccf;
654 
655 	ucce = ioread32be(uccf->p_ucce);
656 	uccm = ioread32be(uccf->p_uccm);
657 	ucce &= uccm;
658 	iowrite32be(ucce, uccf->p_ucce);
659 	if (!ucce)
660 		return IRQ_NONE;
661 
662 	if ((ucce >> 16) & (UCCE_HDLC_RX_EVENTS | UCCE_HDLC_TX_EVENTS)) {
663 		if (napi_schedule_prep(&priv->napi)) {
664 			uccm &= ~((UCCE_HDLC_RX_EVENTS | UCCE_HDLC_TX_EVENTS)
665 				  << 16);
666 			iowrite32be(uccm, uccf->p_uccm);
667 			__napi_schedule(&priv->napi);
668 		}
669 	}
670 
671 	/* Errors and other events */
672 	if (ucce >> 16 & UCC_HDLC_UCCE_BSY)
673 		dev->stats.rx_missed_errors++;
674 	if (ucce >> 16 & UCC_HDLC_UCCE_TXE)
675 		dev->stats.tx_errors++;
676 
677 	return IRQ_HANDLED;
678 }
679 
680 static int uhdlc_ioctl(struct net_device *dev, struct if_settings *ifs)
681 {
682 	const size_t size = sizeof(te1_settings);
683 	te1_settings line;
684 	struct ucc_hdlc_private *priv = netdev_priv(dev);
685 
686 	switch (ifs->type) {
687 	case IF_GET_IFACE:
688 		ifs->type = IF_IFACE_E1;
689 		if (ifs->size < size) {
690 			ifs->size = size; /* data size wanted */
691 			return -ENOBUFS;
692 		}
693 		memset(&line, 0, sizeof(line));
694 		line.clock_type = priv->clocking;
695 
696 		if (copy_to_user(ifs->ifs_ifsu.sync, &line, size))
697 			return -EFAULT;
698 		return 0;
699 
700 	default:
701 		return hdlc_ioctl(dev, ifs);
702 	}
703 }
704 
705 static int uhdlc_open(struct net_device *dev)
706 {
707 	u32 cecr_subblock;
708 	hdlc_device *hdlc = dev_to_hdlc(dev);
709 	struct ucc_hdlc_private *priv = hdlc->priv;
710 	struct ucc_tdm *utdm = priv->utdm;
711 
712 	if (priv->hdlc_busy != 1) {
713 		if (request_irq(priv->ut_info->uf_info.irq,
714 				ucc_hdlc_irq_handler, 0, "hdlc", priv))
715 			return -ENODEV;
716 
717 		cecr_subblock = ucc_fast_get_qe_cr_subblock(
718 					priv->ut_info->uf_info.ucc_num);
719 
720 		qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
721 			     QE_CR_PROTOCOL_UNSPECIFIED, 0);
722 
723 		ucc_fast_enable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
724 
725 		/* Enable the TDM port */
726 		if (priv->tsa)
727 			qe_setbits_8(&utdm->si_regs->siglmr1_h, 0x1 << utdm->tdm_port);
728 
729 		priv->hdlc_busy = 1;
730 		netif_device_attach(priv->ndev);
731 		napi_enable(&priv->napi);
732 		netdev_reset_queue(dev);
733 		netif_start_queue(dev);
734 		hdlc_open(dev);
735 	}
736 
737 	return 0;
738 }
739 
740 static void uhdlc_memclean(struct ucc_hdlc_private *priv)
741 {
742 	qe_muram_free(ioread16be(&priv->ucc_pram->riptr));
743 	qe_muram_free(ioread16be(&priv->ucc_pram->tiptr));
744 
745 	if (priv->rx_bd_base) {
746 		dma_free_coherent(priv->dev,
747 				  RX_BD_RING_LEN * sizeof(struct qe_bd),
748 				  priv->rx_bd_base, priv->dma_rx_bd);
749 
750 		priv->rx_bd_base = NULL;
751 		priv->dma_rx_bd = 0;
752 	}
753 
754 	if (priv->tx_bd_base) {
755 		dma_free_coherent(priv->dev,
756 				  TX_BD_RING_LEN * sizeof(struct qe_bd),
757 				  priv->tx_bd_base, priv->dma_tx_bd);
758 
759 		priv->tx_bd_base = NULL;
760 		priv->dma_tx_bd = 0;
761 	}
762 
763 	if (priv->ucc_pram) {
764 		qe_muram_free(priv->ucc_pram_offset);
765 		priv->ucc_pram = NULL;
766 		priv->ucc_pram_offset = 0;
767 	 }
768 
769 	kfree(priv->rx_skbuff);
770 	priv->rx_skbuff = NULL;
771 
772 	kfree(priv->tx_skbuff);
773 	priv->tx_skbuff = NULL;
774 
775 	if (priv->uf_regs) {
776 		iounmap(priv->uf_regs);
777 		priv->uf_regs = NULL;
778 	}
779 
780 	if (priv->uccf) {
781 		ucc_fast_free(priv->uccf);
782 		priv->uccf = NULL;
783 	}
784 
785 	if (priv->rx_buffer) {
786 		dma_free_coherent(priv->dev,
787 				  RX_BD_RING_LEN * MAX_RX_BUF_LENGTH,
788 				  priv->rx_buffer, priv->dma_rx_addr);
789 		priv->rx_buffer = NULL;
790 		priv->dma_rx_addr = 0;
791 	}
792 
793 	if (priv->tx_buffer) {
794 		dma_free_coherent(priv->dev,
795 				  TX_BD_RING_LEN * MAX_RX_BUF_LENGTH,
796 				  priv->tx_buffer, priv->dma_tx_addr);
797 		priv->tx_buffer = NULL;
798 		priv->dma_tx_addr = 0;
799 	}
800 }
801 
802 static int uhdlc_close(struct net_device *dev)
803 {
804 	struct ucc_hdlc_private *priv = dev_to_hdlc(dev)->priv;
805 	struct ucc_tdm *utdm = priv->utdm;
806 	u32 cecr_subblock;
807 
808 	napi_disable(&priv->napi);
809 	cecr_subblock = ucc_fast_get_qe_cr_subblock(
810 				priv->ut_info->uf_info.ucc_num);
811 
812 	qe_issue_cmd(QE_GRACEFUL_STOP_TX, cecr_subblock,
813 		     (u8)QE_CR_PROTOCOL_UNSPECIFIED, 0);
814 	qe_issue_cmd(QE_CLOSE_RX_BD, cecr_subblock,
815 		     (u8)QE_CR_PROTOCOL_UNSPECIFIED, 0);
816 
817 	if (priv->tsa)
818 		qe_clrbits_8(&utdm->si_regs->siglmr1_h, 0x1 << utdm->tdm_port);
819 
820 	ucc_fast_disable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
821 
822 	free_irq(priv->ut_info->uf_info.irq, priv);
823 	netif_stop_queue(dev);
824 	netdev_reset_queue(dev);
825 	priv->hdlc_busy = 0;
826 
827 	return 0;
828 }
829 
830 static int ucc_hdlc_attach(struct net_device *dev, unsigned short encoding,
831 			   unsigned short parity)
832 {
833 	struct ucc_hdlc_private *priv = dev_to_hdlc(dev)->priv;
834 
835 	if (encoding != ENCODING_NRZ &&
836 	    encoding != ENCODING_NRZI)
837 		return -EINVAL;
838 
839 	if (parity != PARITY_NONE &&
840 	    parity != PARITY_CRC32_PR1_CCITT &&
841 	    parity != PARITY_CRC16_PR0_CCITT &&
842 	    parity != PARITY_CRC16_PR1_CCITT)
843 		return -EINVAL;
844 
845 	priv->encoding = encoding;
846 	priv->parity = parity;
847 
848 	return 0;
849 }
850 
851 #ifdef CONFIG_PM
852 static void store_clk_config(struct ucc_hdlc_private *priv)
853 {
854 	struct qe_mux __iomem *qe_mux_reg = &qe_immr->qmx;
855 
856 	/* store si clk */
857 	priv->cmxsi1cr_h = ioread32be(&qe_mux_reg->cmxsi1cr_h);
858 	priv->cmxsi1cr_l = ioread32be(&qe_mux_reg->cmxsi1cr_l);
859 
860 	/* store si sync */
861 	priv->cmxsi1syr = ioread32be(&qe_mux_reg->cmxsi1syr);
862 
863 	/* store ucc clk */
864 	memcpy_fromio(priv->cmxucr, qe_mux_reg->cmxucr, 4 * sizeof(u32));
865 }
866 
867 static void resume_clk_config(struct ucc_hdlc_private *priv)
868 {
869 	struct qe_mux __iomem *qe_mux_reg = &qe_immr->qmx;
870 
871 	memcpy_toio(qe_mux_reg->cmxucr, priv->cmxucr, 4 * sizeof(u32));
872 
873 	iowrite32be(priv->cmxsi1cr_h, &qe_mux_reg->cmxsi1cr_h);
874 	iowrite32be(priv->cmxsi1cr_l, &qe_mux_reg->cmxsi1cr_l);
875 
876 	iowrite32be(priv->cmxsi1syr, &qe_mux_reg->cmxsi1syr);
877 }
878 
879 static int uhdlc_suspend(struct device *dev)
880 {
881 	struct ucc_hdlc_private *priv = dev_get_drvdata(dev);
882 	struct ucc_fast __iomem *uf_regs;
883 
884 	if (!priv)
885 		return -EINVAL;
886 
887 	if (!netif_running(priv->ndev))
888 		return 0;
889 
890 	netif_device_detach(priv->ndev);
891 	napi_disable(&priv->napi);
892 
893 	uf_regs = priv->uf_regs;
894 
895 	/* backup gumr guemr*/
896 	priv->gumr = ioread32be(&uf_regs->gumr);
897 	priv->guemr = ioread8(&uf_regs->guemr);
898 
899 	priv->ucc_pram_bak = kmalloc(sizeof(*priv->ucc_pram_bak),
900 					GFP_KERNEL);
901 	if (!priv->ucc_pram_bak)
902 		return -ENOMEM;
903 
904 	/* backup HDLC parameter */
905 	memcpy_fromio(priv->ucc_pram_bak, priv->ucc_pram,
906 		      sizeof(struct ucc_hdlc_param));
907 
908 	/* store the clk configuration */
909 	store_clk_config(priv);
910 
911 	/* save power */
912 	ucc_fast_disable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
913 
914 	return 0;
915 }
916 
917 static int uhdlc_resume(struct device *dev)
918 {
919 	struct ucc_hdlc_private *priv = dev_get_drvdata(dev);
920 	struct ucc_tdm *utdm;
921 	struct ucc_tdm_info *ut_info;
922 	struct ucc_fast __iomem *uf_regs;
923 	struct ucc_fast_private *uccf;
924 	struct ucc_fast_info *uf_info;
925 	int i;
926 	u32 cecr_subblock;
927 	u16 bd_status;
928 
929 	if (!priv)
930 		return -EINVAL;
931 
932 	if (!netif_running(priv->ndev))
933 		return 0;
934 
935 	utdm = priv->utdm;
936 	ut_info = priv->ut_info;
937 	uf_info = &ut_info->uf_info;
938 	uf_regs = priv->uf_regs;
939 	uccf = priv->uccf;
940 
941 	/* restore gumr guemr */
942 	iowrite8(priv->guemr, &uf_regs->guemr);
943 	iowrite32be(priv->gumr, &uf_regs->gumr);
944 
945 	/* Set Virtual Fifo registers */
946 	iowrite16be(uf_info->urfs, &uf_regs->urfs);
947 	iowrite16be(uf_info->urfet, &uf_regs->urfet);
948 	iowrite16be(uf_info->urfset, &uf_regs->urfset);
949 	iowrite16be(uf_info->utfs, &uf_regs->utfs);
950 	iowrite16be(uf_info->utfet, &uf_regs->utfet);
951 	iowrite16be(uf_info->utftt, &uf_regs->utftt);
952 	/* utfb, urfb are offsets from MURAM base */
953 	iowrite32be(uccf->ucc_fast_tx_virtual_fifo_base_offset, &uf_regs->utfb);
954 	iowrite32be(uccf->ucc_fast_rx_virtual_fifo_base_offset, &uf_regs->urfb);
955 
956 	/* Rx Tx and sync clock routing */
957 	resume_clk_config(priv);
958 
959 	iowrite32be(uf_info->uccm_mask, &uf_regs->uccm);
960 	iowrite32be(0xffffffff, &uf_regs->ucce);
961 
962 	ucc_fast_disable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
963 
964 	/* rebuild SIRAM */
965 	if (priv->tsa)
966 		ucc_tdm_init(priv->utdm, priv->ut_info);
967 
968 	/* Write to QE CECR, UCCx channel to Stop Transmission */
969 	cecr_subblock = ucc_fast_get_qe_cr_subblock(uf_info->ucc_num);
970 	qe_issue_cmd(QE_STOP_TX, cecr_subblock,
971 		     (u8)QE_CR_PROTOCOL_UNSPECIFIED, 0);
972 
973 	/* Set UPSMR normal mode */
974 	iowrite32be(0, &uf_regs->upsmr);
975 
976 	/* init parameter base */
977 	cecr_subblock = ucc_fast_get_qe_cr_subblock(uf_info->ucc_num);
978 	qe_issue_cmd(QE_ASSIGN_PAGE_TO_DEVICE, cecr_subblock,
979 		     QE_CR_PROTOCOL_UNSPECIFIED, priv->ucc_pram_offset);
980 
981 	priv->ucc_pram = (struct ucc_hdlc_param __iomem *)
982 				qe_muram_addr(priv->ucc_pram_offset);
983 
984 	/* restore ucc parameter */
985 	memcpy_toio(priv->ucc_pram, priv->ucc_pram_bak,
986 		    sizeof(struct ucc_hdlc_param));
987 	kfree(priv->ucc_pram_bak);
988 
989 	/* rebuild BD entry */
990 	for (i = 0; i < RX_BD_RING_LEN; i++) {
991 		if (i < (RX_BD_RING_LEN - 1))
992 			bd_status = R_E_S | R_I_S;
993 		else
994 			bd_status = R_E_S | R_I_S | R_W_S;
995 
996 		priv->rx_bd_base[i].status = cpu_to_be16(bd_status);
997 		priv->rx_bd_base[i].buf = cpu_to_be32(priv->dma_rx_addr + i * MAX_RX_BUF_LENGTH);
998 	}
999 
1000 	for (i = 0; i < TX_BD_RING_LEN; i++) {
1001 		if (i < (TX_BD_RING_LEN - 1))
1002 			bd_status =  T_I_S | T_TC_S;
1003 		else
1004 			bd_status =  T_I_S | T_TC_S | T_W_S;
1005 
1006 		priv->tx_bd_base[i].status = cpu_to_be16(bd_status);
1007 		priv->tx_bd_base[i].buf = cpu_to_be32(priv->dma_tx_addr + i * MAX_RX_BUF_LENGTH);
1008 	}
1009 	dma_wmb();
1010 
1011 	/* if hdlc is busy enable TX and RX */
1012 	if (priv->hdlc_busy == 1) {
1013 		cecr_subblock = ucc_fast_get_qe_cr_subblock(
1014 					priv->ut_info->uf_info.ucc_num);
1015 
1016 		qe_issue_cmd(QE_INIT_TX_RX, cecr_subblock,
1017 			     (u8)QE_CR_PROTOCOL_UNSPECIFIED, 0);
1018 
1019 		ucc_fast_enable(priv->uccf, COMM_DIR_RX | COMM_DIR_TX);
1020 
1021 		/* Enable the TDM port */
1022 		if (priv->tsa)
1023 			qe_setbits_8(&utdm->si_regs->siglmr1_h, 0x1 << utdm->tdm_port);
1024 	}
1025 
1026 	napi_enable(&priv->napi);
1027 	netif_device_attach(priv->ndev);
1028 
1029 	return 0;
1030 }
1031 
1032 static const struct dev_pm_ops uhdlc_pm_ops = {
1033 	.suspend = uhdlc_suspend,
1034 	.resume = uhdlc_resume,
1035 	.freeze = uhdlc_suspend,
1036 	.thaw = uhdlc_resume,
1037 };
1038 
1039 #define HDLC_PM_OPS (&uhdlc_pm_ops)
1040 
1041 #else
1042 
1043 #define HDLC_PM_OPS NULL
1044 
1045 #endif
1046 static void uhdlc_tx_timeout(struct net_device *ndev, unsigned int txqueue)
1047 {
1048 	netdev_err(ndev, "%s\n", __func__);
1049 }
1050 
1051 static const struct net_device_ops uhdlc_ops = {
1052 	.ndo_open       = uhdlc_open,
1053 	.ndo_stop       = uhdlc_close,
1054 	.ndo_start_xmit = hdlc_start_xmit,
1055 	.ndo_siocwandev = uhdlc_ioctl,
1056 	.ndo_tx_timeout	= uhdlc_tx_timeout,
1057 };
1058 
1059 static int hdlc_map_iomem(char *name, int init_flag, void __iomem **ptr)
1060 {
1061 	struct device_node *np;
1062 	struct platform_device *pdev;
1063 	struct resource *res;
1064 	static int siram_init_flag;
1065 	int ret = 0;
1066 
1067 	np = of_find_compatible_node(NULL, NULL, name);
1068 	if (!np)
1069 		return -EINVAL;
1070 
1071 	pdev = of_find_device_by_node(np);
1072 	if (!pdev) {
1073 		pr_err("%pOFn: failed to lookup pdev\n", np);
1074 		of_node_put(np);
1075 		return -EINVAL;
1076 	}
1077 
1078 	of_node_put(np);
1079 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1080 	if (!res) {
1081 		ret = -EINVAL;
1082 		goto error_put_device;
1083 	}
1084 	*ptr = ioremap(res->start, resource_size(res));
1085 	if (!*ptr) {
1086 		ret = -ENOMEM;
1087 		goto error_put_device;
1088 	}
1089 
1090 	/* We've remapped the addresses, and we don't need the device any
1091 	 * more, so we should release it.
1092 	 */
1093 	put_device(&pdev->dev);
1094 
1095 	if (init_flag && siram_init_flag == 0) {
1096 		memset_io(*ptr, 0, resource_size(res));
1097 		siram_init_flag = 1;
1098 	}
1099 	return  0;
1100 
1101 error_put_device:
1102 	put_device(&pdev->dev);
1103 
1104 	return ret;
1105 }
1106 
1107 static int ucc_hdlc_probe(struct platform_device *pdev)
1108 {
1109 	struct device_node *np = pdev->dev.of_node;
1110 	struct ucc_hdlc_private *uhdlc_priv = NULL;
1111 	struct ucc_tdm_info *ut_info;
1112 	struct ucc_tdm *utdm = NULL;
1113 	struct resource res;
1114 	struct net_device *dev;
1115 	hdlc_device *hdlc;
1116 	int ucc_num;
1117 	const char *sprop;
1118 	int ret;
1119 	u32 val;
1120 
1121 	ret = of_property_read_u32_index(np, "cell-index", 0, &val);
1122 	if (ret) {
1123 		dev_err(&pdev->dev, "Invalid ucc property\n");
1124 		return -ENODEV;
1125 	}
1126 
1127 	ucc_num = val - 1;
1128 	if (ucc_num > (UCC_MAX_NUM - 1) || ucc_num < 0) {
1129 		dev_err(&pdev->dev, ": Invalid UCC num\n");
1130 		return -EINVAL;
1131 	}
1132 
1133 	memcpy(&utdm_info[ucc_num], &utdm_primary_info,
1134 	       sizeof(utdm_primary_info));
1135 
1136 	ut_info = &utdm_info[ucc_num];
1137 	ut_info->uf_info.ucc_num = ucc_num;
1138 
1139 	sprop = of_get_property(np, "rx-clock-name", NULL);
1140 	if (sprop) {
1141 		ut_info->uf_info.rx_clock = qe_clock_source(sprop);
1142 		if ((ut_info->uf_info.rx_clock < QE_CLK_NONE) ||
1143 		    (ut_info->uf_info.rx_clock > QE_CLK24)) {
1144 			dev_err(&pdev->dev, "Invalid rx-clock-name property\n");
1145 			return -EINVAL;
1146 		}
1147 	} else {
1148 		dev_err(&pdev->dev, "Invalid rx-clock-name property\n");
1149 		return -EINVAL;
1150 	}
1151 
1152 	sprop = of_get_property(np, "tx-clock-name", NULL);
1153 	if (sprop) {
1154 		ut_info->uf_info.tx_clock = qe_clock_source(sprop);
1155 		if ((ut_info->uf_info.tx_clock < QE_CLK_NONE) ||
1156 		    (ut_info->uf_info.tx_clock > QE_CLK24)) {
1157 			dev_err(&pdev->dev, "Invalid tx-clock-name property\n");
1158 			return -EINVAL;
1159 		}
1160 	} else {
1161 		dev_err(&pdev->dev, "Invalid tx-clock-name property\n");
1162 		return -EINVAL;
1163 	}
1164 
1165 	ret = of_address_to_resource(np, 0, &res);
1166 	if (ret)
1167 		return -EINVAL;
1168 
1169 	ut_info->uf_info.regs = res.start;
1170 	ut_info->uf_info.irq = irq_of_parse_and_map(np, 0);
1171 
1172 	uhdlc_priv = kzalloc(sizeof(*uhdlc_priv), GFP_KERNEL);
1173 	if (!uhdlc_priv)
1174 		return -ENOMEM;
1175 
1176 	dev_set_drvdata(&pdev->dev, uhdlc_priv);
1177 	uhdlc_priv->dev = &pdev->dev;
1178 	uhdlc_priv->ut_info = ut_info;
1179 
1180 	if (of_get_property(np, "fsl,tdm-interface", NULL))
1181 		uhdlc_priv->tsa = 1;
1182 
1183 	if (of_get_property(np, "fsl,ucc-internal-loopback", NULL))
1184 		uhdlc_priv->loopback = 1;
1185 
1186 	if (of_get_property(np, "fsl,hdlc-bus", NULL))
1187 		uhdlc_priv->hdlc_bus = 1;
1188 
1189 	if (uhdlc_priv->tsa == 1) {
1190 		utdm = kzalloc(sizeof(*utdm), GFP_KERNEL);
1191 		if (!utdm) {
1192 			ret = -ENOMEM;
1193 			dev_err(&pdev->dev, "No mem to alloc ucc tdm data\n");
1194 			goto free_uhdlc_priv;
1195 		}
1196 		uhdlc_priv->utdm = utdm;
1197 		ret = ucc_of_parse_tdm(np, utdm, ut_info);
1198 		if (ret)
1199 			goto free_utdm;
1200 
1201 		ret = hdlc_map_iomem("fsl,t1040-qe-si", 0,
1202 				     (void __iomem **)&utdm->si_regs);
1203 		if (ret)
1204 			goto free_utdm;
1205 		ret = hdlc_map_iomem("fsl,t1040-qe-siram", 1,
1206 				     (void __iomem **)&utdm->siram);
1207 		if (ret)
1208 			goto unmap_si_regs;
1209 	}
1210 
1211 	if (of_property_read_u16(np, "fsl,hmask", &uhdlc_priv->hmask))
1212 		uhdlc_priv->hmask = DEFAULT_ADDR_MASK;
1213 
1214 	ret = uhdlc_init(uhdlc_priv);
1215 	if (ret) {
1216 		dev_err(&pdev->dev, "Failed to init uhdlc\n");
1217 		goto undo_uhdlc_init;
1218 	}
1219 
1220 	dev = alloc_hdlcdev(uhdlc_priv);
1221 	if (!dev) {
1222 		ret = -ENOMEM;
1223 		pr_err("ucc_hdlc: unable to allocate memory\n");
1224 		goto undo_uhdlc_init;
1225 	}
1226 
1227 	uhdlc_priv->ndev = dev;
1228 	hdlc = dev_to_hdlc(dev);
1229 	dev->tx_queue_len = 16;
1230 	dev->netdev_ops = &uhdlc_ops;
1231 	dev->watchdog_timeo = 2 * HZ;
1232 	hdlc->attach = ucc_hdlc_attach;
1233 	hdlc->xmit = ucc_hdlc_tx;
1234 	netif_napi_add_weight(dev, &uhdlc_priv->napi, ucc_hdlc_poll, 32);
1235 	if (register_hdlc_device(dev)) {
1236 		ret = -ENOBUFS;
1237 		pr_err("ucc_hdlc: unable to register hdlc device\n");
1238 		goto free_dev;
1239 	}
1240 
1241 	return 0;
1242 
1243 free_dev:
1244 	free_netdev(dev);
1245 undo_uhdlc_init:
1246 	iounmap(utdm->siram);
1247 unmap_si_regs:
1248 	iounmap(utdm->si_regs);
1249 free_utdm:
1250 	if (uhdlc_priv->tsa)
1251 		kfree(utdm);
1252 free_uhdlc_priv:
1253 	kfree(uhdlc_priv);
1254 	return ret;
1255 }
1256 
1257 static int ucc_hdlc_remove(struct platform_device *pdev)
1258 {
1259 	struct ucc_hdlc_private *priv = dev_get_drvdata(&pdev->dev);
1260 
1261 	uhdlc_memclean(priv);
1262 
1263 	if (priv->utdm->si_regs) {
1264 		iounmap(priv->utdm->si_regs);
1265 		priv->utdm->si_regs = NULL;
1266 	}
1267 
1268 	if (priv->utdm->siram) {
1269 		iounmap(priv->utdm->siram);
1270 		priv->utdm->siram = NULL;
1271 	}
1272 	kfree(priv);
1273 
1274 	dev_info(&pdev->dev, "UCC based hdlc module removed\n");
1275 
1276 	return 0;
1277 }
1278 
1279 static const struct of_device_id fsl_ucc_hdlc_of_match[] = {
1280 	{
1281 	.compatible = "fsl,ucc-hdlc",
1282 	},
1283 	{},
1284 };
1285 
1286 MODULE_DEVICE_TABLE(of, fsl_ucc_hdlc_of_match);
1287 
1288 static struct platform_driver ucc_hdlc_driver = {
1289 	.probe	= ucc_hdlc_probe,
1290 	.remove	= ucc_hdlc_remove,
1291 	.driver	= {
1292 		.name		= DRV_NAME,
1293 		.pm		= HDLC_PM_OPS,
1294 		.of_match_table	= fsl_ucc_hdlc_of_match,
1295 	},
1296 };
1297 
1298 module_platform_driver(ucc_hdlc_driver);
1299 MODULE_LICENSE("GPL");
1300 MODULE_DESCRIPTION(DRV_DESC);
1301