1 // SPDX-License-Identifier: GPL-2.0+
2 /* Copyright (c) 2020 Intel Corporation. */
3 
4 #include <linux/clk.h>
5 #include <linux/completion.h>
6 #include <linux/dmaengine.h>
7 #include <linux/dma-direction.h>
8 #include <linux/dma-mapping.h>
9 #include <linux/err.h>
10 #include <linux/init.h>
11 #include <linux/iopoll.h>
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 
15 #include <linux/mtd/mtd.h>
16 #include <linux/mtd/rawnand.h>
17 #include <linux/mtd/nand.h>
18 
19 #include <linux/platform_device.h>
20 #include <linux/sched.h>
21 #include <linux/slab.h>
22 #include <linux/types.h>
23 #include <asm/unaligned.h>
24 
25 #define EBU_CLC			0x000
26 #define EBU_CLC_RST		0x00000000u
27 
28 #define EBU_ADDR_SEL(n)		(0x020 + (n) * 4)
29 /* 5 bits 26:22 included for comparison in the ADDR_SELx */
30 #define EBU_ADDR_MASK(x)	((x) << 4)
31 #define EBU_ADDR_SEL_REGEN	0x1
32 
33 #define EBU_BUSCON(n)		(0x060 + (n) * 4)
34 #define EBU_BUSCON_CMULT_V4	0x1
35 #define EBU_BUSCON_RECOVC(n)	((n) << 2)
36 #define EBU_BUSCON_HOLDC(n)	((n) << 4)
37 #define EBU_BUSCON_WAITRDC(n)	((n) << 6)
38 #define EBU_BUSCON_WAITWRC(n)	((n) << 8)
39 #define EBU_BUSCON_BCGEN_CS	0x0
40 #define EBU_BUSCON_SETUP_EN	BIT(22)
41 #define EBU_BUSCON_ALEC		0xC000
42 
43 #define EBU_CON			0x0B0
44 #define EBU_CON_NANDM_EN	BIT(0)
45 #define EBU_CON_NANDM_DIS	0x0
46 #define EBU_CON_CSMUX_E_EN	BIT(1)
47 #define EBU_CON_ALE_P_LOW	BIT(2)
48 #define EBU_CON_CLE_P_LOW	BIT(3)
49 #define EBU_CON_CS_P_LOW	BIT(4)
50 #define EBU_CON_SE_P_LOW	BIT(5)
51 #define EBU_CON_WP_P_LOW	BIT(6)
52 #define EBU_CON_PRE_P_LOW	BIT(7)
53 #define EBU_CON_IN_CS_S(n)	((n) << 8)
54 #define EBU_CON_OUT_CS_S(n)	((n) << 10)
55 #define EBU_CON_LAT_EN_CS_P	((0x3D) << 18)
56 
57 #define EBU_WAIT		0x0B4
58 #define EBU_WAIT_RDBY		BIT(0)
59 #define EBU_WAIT_WR_C		BIT(3)
60 
61 #define HSNAND_CTL1		0x110
62 #define HSNAND_CTL1_ADDR_SHIFT	24
63 
64 #define HSNAND_CTL2		0x114
65 #define HSNAND_CTL2_ADDR_SHIFT	8
66 #define HSNAND_CTL2_CYC_N_V5	(0x2 << 16)
67 
68 #define HSNAND_INT_MSK_CTL	0x124
69 #define HSNAND_INT_MSK_CTL_WR_C	BIT(4)
70 
71 #define HSNAND_INT_STA		0x128
72 #define HSNAND_INT_STA_WR_C	BIT(4)
73 
74 #define HSNAND_CTL		0x130
75 #define HSNAND_CTL_ENABLE_ECC	BIT(0)
76 #define HSNAND_CTL_GO		BIT(2)
77 #define HSNAND_CTL_CE_SEL_CS(n)	BIT(3 + (n))
78 #define HSNAND_CTL_RW_READ	0x0
79 #define HSNAND_CTL_RW_WRITE	BIT(10)
80 #define HSNAND_CTL_ECC_OFF_V8TH	BIT(11)
81 #define HSNAND_CTL_CKFF_EN	0x0
82 #define HSNAND_CTL_MSG_EN	BIT(17)
83 
84 #define HSNAND_PARA0		0x13c
85 #define HSNAND_PARA0_PAGE_V8192	0x3
86 #define HSNAND_PARA0_PIB_V256	(0x3 << 4)
87 #define HSNAND_PARA0_BYP_EN_NP	0x0
88 #define HSNAND_PARA0_BYP_DEC_NP	0x0
89 #define HSNAND_PARA0_TYPE_ONFI	BIT(18)
90 #define HSNAND_PARA0_ADEP_EN	BIT(21)
91 
92 #define HSNAND_CMSG_0		0x150
93 #define HSNAND_CMSG_1		0x154
94 
95 #define HSNAND_ALE_OFFS		BIT(2)
96 #define HSNAND_CLE_OFFS		BIT(3)
97 #define HSNAND_CS_OFFS		BIT(4)
98 
99 #define HSNAND_ECC_OFFSET	0x008
100 
101 #define NAND_DATA_IFACE_CHECK_ONLY	-1
102 
103 #define MAX_CS	2
104 
105 #define HZ_PER_MHZ	1000000L
106 #define USEC_PER_SEC	1000000L
107 
108 struct ebu_nand_cs {
109 	void __iomem *chipaddr;
110 	dma_addr_t nand_pa;
111 	u32 addr_sel;
112 };
113 
114 struct ebu_nand_controller {
115 	struct nand_controller controller;
116 	struct nand_chip chip;
117 	struct device *dev;
118 	void __iomem *ebu;
119 	void __iomem *hsnand;
120 	struct dma_chan *dma_tx;
121 	struct dma_chan *dma_rx;
122 	struct completion dma_access_complete;
123 	unsigned long clk_rate;
124 	struct clk *clk;
125 	u32 nd_para0;
126 	u8 cs_num;
127 	struct ebu_nand_cs cs[MAX_CS];
128 };
129 
130 static inline struct ebu_nand_controller *nand_to_ebu(struct nand_chip *chip)
131 {
132 	return container_of(chip, struct ebu_nand_controller, chip);
133 }
134 
135 static int ebu_nand_waitrdy(struct nand_chip *chip, int timeout_ms)
136 {
137 	struct ebu_nand_controller *ctrl = nand_to_ebu(chip);
138 	u32 status;
139 
140 	return readl_poll_timeout(ctrl->ebu + EBU_WAIT, status,
141 				  (status & EBU_WAIT_RDBY) ||
142 				  (status & EBU_WAIT_WR_C), 20, timeout_ms);
143 }
144 
145 static u8 ebu_nand_readb(struct nand_chip *chip)
146 {
147 	struct ebu_nand_controller *ebu_host = nand_get_controller_data(chip);
148 	u8 cs_num = ebu_host->cs_num;
149 	u8 val;
150 
151 	val = readb(ebu_host->cs[cs_num].chipaddr + HSNAND_CS_OFFS);
152 	ebu_nand_waitrdy(chip, 1000);
153 	return val;
154 }
155 
156 static void ebu_nand_writeb(struct nand_chip *chip, u32 offset, u8 value)
157 {
158 	struct ebu_nand_controller *ebu_host = nand_get_controller_data(chip);
159 	u8 cs_num = ebu_host->cs_num;
160 
161 	writeb(value, ebu_host->cs[cs_num].chipaddr + offset);
162 	ebu_nand_waitrdy(chip, 1000);
163 }
164 
165 static void ebu_read_buf(struct nand_chip *chip, u_char *buf, unsigned int len)
166 {
167 	int i;
168 
169 	for (i = 0; i < len; i++)
170 		buf[i] = ebu_nand_readb(chip);
171 }
172 
173 static void ebu_write_buf(struct nand_chip *chip, const u_char *buf, int len)
174 {
175 	int i;
176 
177 	for (i = 0; i < len; i++)
178 		ebu_nand_writeb(chip, HSNAND_CS_OFFS, buf[i]);
179 }
180 
181 static void ebu_nand_disable(struct nand_chip *chip)
182 {
183 	struct ebu_nand_controller *ebu_host = nand_get_controller_data(chip);
184 
185 	writel(0, ebu_host->ebu + EBU_CON);
186 }
187 
188 static void ebu_select_chip(struct nand_chip *chip)
189 {
190 	struct ebu_nand_controller *ebu_host = nand_get_controller_data(chip);
191 	void __iomem *nand_con = ebu_host->ebu + EBU_CON;
192 	u32 cs = ebu_host->cs_num;
193 
194 	writel(EBU_CON_NANDM_EN | EBU_CON_CSMUX_E_EN | EBU_CON_CS_P_LOW |
195 	       EBU_CON_SE_P_LOW | EBU_CON_WP_P_LOW | EBU_CON_PRE_P_LOW |
196 	       EBU_CON_IN_CS_S(cs) | EBU_CON_OUT_CS_S(cs) |
197 	       EBU_CON_LAT_EN_CS_P, nand_con);
198 }
199 
200 static int ebu_nand_set_timings(struct nand_chip *chip, int csline,
201 				const struct nand_interface_config *conf)
202 {
203 	struct ebu_nand_controller *ctrl = nand_to_ebu(chip);
204 	unsigned int rate = clk_get_rate(ctrl->clk) / HZ_PER_MHZ;
205 	unsigned int period = DIV_ROUND_UP(USEC_PER_SEC, rate);
206 	const struct nand_sdr_timings *timings;
207 	u32 trecov, thold, twrwait, trdwait;
208 	u32 reg = 0;
209 
210 	timings = nand_get_sdr_timings(conf);
211 	if (IS_ERR(timings))
212 		return PTR_ERR(timings);
213 
214 	if (csline == NAND_DATA_IFACE_CHECK_ONLY)
215 		return 0;
216 
217 	trecov = DIV_ROUND_UP(max(timings->tREA_max, timings->tREH_min),
218 			      period);
219 	reg |= EBU_BUSCON_RECOVC(trecov);
220 
221 	thold = DIV_ROUND_UP(max(timings->tDH_min, timings->tDS_min), period);
222 	reg |= EBU_BUSCON_HOLDC(thold);
223 
224 	trdwait = DIV_ROUND_UP(max(timings->tRC_min, timings->tREH_min),
225 			       period);
226 	reg |= EBU_BUSCON_WAITRDC(trdwait);
227 
228 	twrwait = DIV_ROUND_UP(max(timings->tWC_min, timings->tWH_min), period);
229 	reg |= EBU_BUSCON_WAITWRC(twrwait);
230 
231 	reg |= EBU_BUSCON_CMULT_V4 | EBU_BUSCON_BCGEN_CS | EBU_BUSCON_ALEC |
232 		EBU_BUSCON_SETUP_EN;
233 
234 	writel(reg, ctrl->ebu + EBU_BUSCON(ctrl->cs_num));
235 
236 	return 0;
237 }
238 
239 static int ebu_nand_ooblayout_ecc(struct mtd_info *mtd, int section,
240 				  struct mtd_oob_region *oobregion)
241 {
242 	struct nand_chip *chip = mtd_to_nand(mtd);
243 
244 	if (section)
245 		return -ERANGE;
246 
247 	oobregion->offset = HSNAND_ECC_OFFSET;
248 	oobregion->length = chip->ecc.total;
249 
250 	return 0;
251 }
252 
253 static int ebu_nand_ooblayout_free(struct mtd_info *mtd, int section,
254 				   struct mtd_oob_region *oobregion)
255 {
256 	struct nand_chip *chip = mtd_to_nand(mtd);
257 
258 	if (section)
259 		return -ERANGE;
260 
261 	oobregion->offset = chip->ecc.total + HSNAND_ECC_OFFSET;
262 	oobregion->length = mtd->oobsize - oobregion->offset;
263 
264 	return 0;
265 }
266 
267 static const struct mtd_ooblayout_ops ebu_nand_ooblayout_ops = {
268 	.ecc = ebu_nand_ooblayout_ecc,
269 	.free = ebu_nand_ooblayout_free,
270 };
271 
272 static void ebu_dma_rx_callback(void *cookie)
273 {
274 	struct ebu_nand_controller *ebu_host = cookie;
275 
276 	dmaengine_terminate_async(ebu_host->dma_rx);
277 
278 	complete(&ebu_host->dma_access_complete);
279 }
280 
281 static void ebu_dma_tx_callback(void *cookie)
282 {
283 	struct ebu_nand_controller *ebu_host = cookie;
284 
285 	dmaengine_terminate_async(ebu_host->dma_tx);
286 
287 	complete(&ebu_host->dma_access_complete);
288 }
289 
290 static int ebu_dma_start(struct ebu_nand_controller *ebu_host, u32 dir,
291 			 const u8 *buf, u32 len)
292 {
293 	struct dma_async_tx_descriptor *tx;
294 	struct completion *dma_completion;
295 	dma_async_tx_callback callback;
296 	struct dma_chan *chan;
297 	dma_cookie_t cookie;
298 	unsigned long flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
299 	dma_addr_t buf_dma;
300 	int ret;
301 	u32 timeout;
302 
303 	if (dir == DMA_DEV_TO_MEM) {
304 		chan = ebu_host->dma_rx;
305 		dma_completion = &ebu_host->dma_access_complete;
306 		callback = ebu_dma_rx_callback;
307 	} else {
308 		chan = ebu_host->dma_tx;
309 		dma_completion = &ebu_host->dma_access_complete;
310 		callback = ebu_dma_tx_callback;
311 	}
312 
313 	buf_dma = dma_map_single(chan->device->dev, (void *)buf, len, dir);
314 	if (dma_mapping_error(chan->device->dev, buf_dma)) {
315 		dev_err(ebu_host->dev, "Failed to map DMA buffer\n");
316 		ret = -EIO;
317 		goto err_unmap;
318 	}
319 
320 	tx = dmaengine_prep_slave_single(chan, buf_dma, len, dir, flags);
321 	if (!tx)
322 		return -ENXIO;
323 
324 	tx->callback = callback;
325 	tx->callback_param = ebu_host;
326 	cookie = tx->tx_submit(tx);
327 
328 	ret = dma_submit_error(cookie);
329 	if (ret) {
330 		dev_err(ebu_host->dev, "dma_submit_error %d\n", cookie);
331 		ret = -EIO;
332 		goto err_unmap;
333 	}
334 
335 	init_completion(dma_completion);
336 	dma_async_issue_pending(chan);
337 
338 	/* Wait DMA to finish the data transfer.*/
339 	timeout = wait_for_completion_timeout(dma_completion, msecs_to_jiffies(1000));
340 	if (!timeout) {
341 		dev_err(ebu_host->dev, "I/O Error in DMA RX (status %d)\n",
342 			dmaengine_tx_status(chan, cookie, NULL));
343 		dmaengine_terminate_sync(chan);
344 		ret = -ETIMEDOUT;
345 		goto err_unmap;
346 	}
347 
348 	return 0;
349 
350 err_unmap:
351 	dma_unmap_single(ebu_host->dev, buf_dma, len, dir);
352 
353 	return ret;
354 }
355 
356 static void ebu_nand_trigger(struct ebu_nand_controller *ebu_host,
357 			     int page, u32 cmd)
358 {
359 	unsigned int val;
360 
361 	val = cmd | (page & 0xFF) << HSNAND_CTL1_ADDR_SHIFT;
362 	writel(val, ebu_host->hsnand + HSNAND_CTL1);
363 	val = (page & 0xFFFF00) >> 8 | HSNAND_CTL2_CYC_N_V5;
364 	writel(val, ebu_host->hsnand + HSNAND_CTL2);
365 
366 	writel(ebu_host->nd_para0, ebu_host->hsnand + HSNAND_PARA0);
367 
368 	/* clear first, will update later */
369 	writel(0xFFFFFFFF, ebu_host->hsnand + HSNAND_CMSG_0);
370 	writel(0xFFFFFFFF, ebu_host->hsnand + HSNAND_CMSG_1);
371 
372 	writel(HSNAND_INT_MSK_CTL_WR_C,
373 	       ebu_host->hsnand + HSNAND_INT_MSK_CTL);
374 
375 	if (!cmd)
376 		val = HSNAND_CTL_RW_READ;
377 	else
378 		val = HSNAND_CTL_RW_WRITE;
379 
380 	writel(HSNAND_CTL_MSG_EN | HSNAND_CTL_CKFF_EN |
381 	       HSNAND_CTL_ECC_OFF_V8TH | HSNAND_CTL_CE_SEL_CS(ebu_host->cs_num) |
382 	       HSNAND_CTL_ENABLE_ECC | HSNAND_CTL_GO | val,
383 	       ebu_host->hsnand + HSNAND_CTL);
384 }
385 
386 static int ebu_nand_read_page_hwecc(struct nand_chip *chip, u8 *buf,
387 				    int oob_required, int page)
388 {
389 	struct mtd_info *mtd = nand_to_mtd(chip);
390 	struct ebu_nand_controller *ebu_host = nand_get_controller_data(chip);
391 	int ret, reg_data;
392 
393 	ebu_nand_trigger(ebu_host, page, NAND_CMD_READ0);
394 
395 	ret = ebu_dma_start(ebu_host, DMA_DEV_TO_MEM, buf, mtd->writesize);
396 	if (ret)
397 		return ret;
398 
399 	if (oob_required)
400 		chip->ecc.read_oob(chip, page);
401 
402 	reg_data = readl(ebu_host->hsnand + HSNAND_CTL);
403 	reg_data &= ~HSNAND_CTL_GO;
404 	writel(reg_data, ebu_host->hsnand + HSNAND_CTL);
405 
406 	return 0;
407 }
408 
409 static int ebu_nand_write_page_hwecc(struct nand_chip *chip, const u8 *buf,
410 				     int oob_required, int page)
411 {
412 	struct mtd_info *mtd = nand_to_mtd(chip);
413 	struct ebu_nand_controller *ebu_host = nand_get_controller_data(chip);
414 	void __iomem *int_sta = ebu_host->hsnand + HSNAND_INT_STA;
415 	int reg_data, ret, val;
416 	u32 reg;
417 
418 	ebu_nand_trigger(ebu_host, page, NAND_CMD_SEQIN);
419 
420 	ret = ebu_dma_start(ebu_host, DMA_MEM_TO_DEV, buf, mtd->writesize);
421 	if (ret)
422 		return ret;
423 
424 	if (oob_required) {
425 		reg = get_unaligned_le32(chip->oob_poi);
426 		writel(reg, ebu_host->hsnand + HSNAND_CMSG_0);
427 
428 		reg = get_unaligned_le32(chip->oob_poi + 4);
429 		writel(reg, ebu_host->hsnand + HSNAND_CMSG_1);
430 	}
431 
432 	ret = readl_poll_timeout_atomic(int_sta, val, !(val & HSNAND_INT_STA_WR_C),
433 					10, 1000);
434 	if (ret)
435 		return ret;
436 
437 	reg_data = readl(ebu_host->hsnand + HSNAND_CTL);
438 	reg_data &= ~HSNAND_CTL_GO;
439 	writel(reg_data, ebu_host->hsnand + HSNAND_CTL);
440 
441 	return 0;
442 }
443 
444 static const u8 ecc_strength[] = { 1, 1, 4, 8, 24, 32, 40, 60, };
445 
446 static int ebu_nand_attach_chip(struct nand_chip *chip)
447 {
448 	struct mtd_info *mtd = nand_to_mtd(chip);
449 	struct ebu_nand_controller *ebu_host = nand_get_controller_data(chip);
450 	u32 ecc_steps, ecc_bytes, ecc_total, pagesize, pg_per_blk;
451 	u32 ecc_strength_ds = chip->ecc.strength;
452 	u32 ecc_size = chip->ecc.size;
453 	u32 writesize = mtd->writesize;
454 	u32 blocksize = mtd->erasesize;
455 	int bch_algo, start, val;
456 
457 	/* Default to an ECC size of 512 */
458 	if (!chip->ecc.size)
459 		chip->ecc.size = 512;
460 
461 	switch (ecc_size) {
462 	case 512:
463 		start = 1;
464 		if (!ecc_strength_ds)
465 			ecc_strength_ds = 4;
466 		break;
467 	case 1024:
468 		start = 4;
469 		if (!ecc_strength_ds)
470 			ecc_strength_ds = 32;
471 		break;
472 	default:
473 		return -EINVAL;
474 	}
475 
476 	/* BCH ECC algorithm Settings for number of bits per 512B/1024B */
477 	bch_algo = round_up(start + 1, 4);
478 	for (val = start; val < bch_algo; val++) {
479 		if (ecc_strength_ds == ecc_strength[val])
480 			break;
481 	}
482 	if (val == bch_algo)
483 		return -EINVAL;
484 
485 	if (ecc_strength_ds == 8)
486 		ecc_bytes = 14;
487 	else
488 		ecc_bytes = DIV_ROUND_UP(ecc_strength_ds * fls(8 * ecc_size), 8);
489 
490 	ecc_steps = writesize / ecc_size;
491 	ecc_total = ecc_steps * ecc_bytes;
492 	if ((ecc_total + 8) > mtd->oobsize)
493 		return -ERANGE;
494 
495 	chip->ecc.total = ecc_total;
496 	pagesize = fls(writesize >> 11);
497 	if (pagesize > HSNAND_PARA0_PAGE_V8192)
498 		return -ERANGE;
499 
500 	pg_per_blk = fls((blocksize / writesize) >> 6) / 8;
501 	if (pg_per_blk > HSNAND_PARA0_PIB_V256)
502 		return -ERANGE;
503 
504 	ebu_host->nd_para0 = pagesize | pg_per_blk | HSNAND_PARA0_BYP_EN_NP |
505 			     HSNAND_PARA0_BYP_DEC_NP | HSNAND_PARA0_ADEP_EN |
506 			     HSNAND_PARA0_TYPE_ONFI | (val << 29);
507 
508 	mtd_set_ooblayout(mtd, &ebu_nand_ooblayout_ops);
509 	chip->ecc.read_page = ebu_nand_read_page_hwecc;
510 	chip->ecc.write_page = ebu_nand_write_page_hwecc;
511 
512 	return 0;
513 }
514 
515 static int ebu_nand_exec_op(struct nand_chip *chip,
516 			    const struct nand_operation *op, bool check_only)
517 {
518 	const struct nand_op_instr *instr = NULL;
519 	unsigned int op_id;
520 	int i, timeout_ms, ret = 0;
521 
522 	if (check_only)
523 		return 0;
524 
525 	ebu_select_chip(chip);
526 	for (op_id = 0; op_id < op->ninstrs; op_id++) {
527 		instr = &op->instrs[op_id];
528 
529 		switch (instr->type) {
530 		case NAND_OP_CMD_INSTR:
531 			ebu_nand_writeb(chip, HSNAND_CLE_OFFS | HSNAND_CS_OFFS,
532 					instr->ctx.cmd.opcode);
533 			break;
534 
535 		case NAND_OP_ADDR_INSTR:
536 			for (i = 0; i < instr->ctx.addr.naddrs; i++)
537 				ebu_nand_writeb(chip,
538 						HSNAND_ALE_OFFS | HSNAND_CS_OFFS,
539 						instr->ctx.addr.addrs[i]);
540 			break;
541 
542 		case NAND_OP_DATA_IN_INSTR:
543 			ebu_read_buf(chip, instr->ctx.data.buf.in,
544 				     instr->ctx.data.len);
545 			break;
546 
547 		case NAND_OP_DATA_OUT_INSTR:
548 			ebu_write_buf(chip, instr->ctx.data.buf.out,
549 				      instr->ctx.data.len);
550 			break;
551 
552 		case NAND_OP_WAITRDY_INSTR:
553 			timeout_ms = instr->ctx.waitrdy.timeout_ms * 1000;
554 			ret = ebu_nand_waitrdy(chip, timeout_ms);
555 			break;
556 		}
557 	}
558 
559 	return ret;
560 }
561 
562 static const struct nand_controller_ops ebu_nand_controller_ops = {
563 	.attach_chip = ebu_nand_attach_chip,
564 	.setup_interface = ebu_nand_set_timings,
565 	.exec_op = ebu_nand_exec_op,
566 };
567 
568 static void ebu_dma_cleanup(struct ebu_nand_controller *ebu_host)
569 {
570 	if (ebu_host->dma_rx)
571 		dma_release_channel(ebu_host->dma_rx);
572 
573 	if (ebu_host->dma_tx)
574 		dma_release_channel(ebu_host->dma_tx);
575 }
576 
577 static int ebu_nand_probe(struct platform_device *pdev)
578 {
579 	struct device *dev = &pdev->dev;
580 	struct ebu_nand_controller *ebu_host;
581 	struct nand_chip *nand;
582 	struct mtd_info *mtd;
583 	struct resource *res;
584 	char *resname;
585 	int ret;
586 	u32 cs;
587 
588 	ebu_host = devm_kzalloc(dev, sizeof(*ebu_host), GFP_KERNEL);
589 	if (!ebu_host)
590 		return -ENOMEM;
591 
592 	ebu_host->dev = dev;
593 	nand_controller_init(&ebu_host->controller);
594 
595 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "ebunand");
596 	ebu_host->ebu = devm_ioremap_resource(&pdev->dev, res);
597 	if (IS_ERR(ebu_host->ebu))
598 		return PTR_ERR(ebu_host->ebu);
599 
600 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "hsnand");
601 	ebu_host->hsnand = devm_ioremap_resource(&pdev->dev, res);
602 	if (IS_ERR(ebu_host->hsnand))
603 		return PTR_ERR(ebu_host->hsnand);
604 
605 	ret = device_property_read_u32(dev, "reg", &cs);
606 	if (ret) {
607 		dev_err(dev, "failed to get chip select: %d\n", ret);
608 		return ret;
609 	}
610 	ebu_host->cs_num = cs;
611 
612 	resname = devm_kasprintf(dev, GFP_KERNEL, "nand_cs%d", cs);
613 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, resname);
614 	ebu_host->cs[cs].chipaddr = devm_ioremap_resource(dev, res);
615 	ebu_host->cs[cs].nand_pa = res->start;
616 	if (IS_ERR(ebu_host->cs[cs].chipaddr))
617 		return PTR_ERR(ebu_host->cs[cs].chipaddr);
618 
619 	ebu_host->clk = devm_clk_get(dev, NULL);
620 	if (IS_ERR(ebu_host->clk))
621 		return dev_err_probe(dev, PTR_ERR(ebu_host->clk),
622 				     "failed to get clock\n");
623 
624 	ret = clk_prepare_enable(ebu_host->clk);
625 	if (ret) {
626 		dev_err(dev, "failed to enable clock: %d\n", ret);
627 		return ret;
628 	}
629 	ebu_host->clk_rate = clk_get_rate(ebu_host->clk);
630 
631 	ebu_host->dma_tx = dma_request_chan(dev, "tx");
632 	if (IS_ERR(ebu_host->dma_tx))
633 		return dev_err_probe(dev, PTR_ERR(ebu_host->dma_tx),
634 				     "failed to request DMA tx chan!.\n");
635 
636 	ebu_host->dma_rx = dma_request_chan(dev, "rx");
637 	if (IS_ERR(ebu_host->dma_rx))
638 		return dev_err_probe(dev, PTR_ERR(ebu_host->dma_rx),
639 				     "failed to request DMA rx chan!.\n");
640 
641 	resname = devm_kasprintf(dev, GFP_KERNEL, "addr_sel%d", cs);
642 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, resname);
643 	if (!res)
644 		return -EINVAL;
645 	ebu_host->cs[cs].addr_sel = res->start;
646 	writel(ebu_host->cs[cs].addr_sel | EBU_ADDR_MASK(5) | EBU_ADDR_SEL_REGEN,
647 	       ebu_host->ebu + EBU_ADDR_SEL(cs));
648 
649 	nand_set_flash_node(&ebu_host->chip, dev->of_node);
650 
651 	mtd = nand_to_mtd(&ebu_host->chip);
652 	if (!mtd->name) {
653 		dev_err(ebu_host->dev, "NAND label property is mandatory\n");
654 		return -EINVAL;
655 	}
656 
657 	mtd->dev.parent = dev;
658 	ebu_host->dev = dev;
659 
660 	platform_set_drvdata(pdev, ebu_host);
661 	nand_set_controller_data(&ebu_host->chip, ebu_host);
662 
663 	nand = &ebu_host->chip;
664 	nand->controller = &ebu_host->controller;
665 	nand->controller->ops = &ebu_nand_controller_ops;
666 
667 	/* Scan to find existence of the device */
668 	ret = nand_scan(&ebu_host->chip, 1);
669 	if (ret)
670 		goto err_cleanup_dma;
671 
672 	ret = mtd_device_register(mtd, NULL, 0);
673 	if (ret)
674 		goto err_clean_nand;
675 
676 	return 0;
677 
678 err_clean_nand:
679 	nand_cleanup(&ebu_host->chip);
680 err_cleanup_dma:
681 	ebu_dma_cleanup(ebu_host);
682 	clk_disable_unprepare(ebu_host->clk);
683 
684 	return ret;
685 }
686 
687 static int ebu_nand_remove(struct platform_device *pdev)
688 {
689 	struct ebu_nand_controller *ebu_host = platform_get_drvdata(pdev);
690 	int ret;
691 
692 	ret = mtd_device_unregister(nand_to_mtd(&ebu_host->chip));
693 	WARN_ON(ret);
694 	nand_cleanup(&ebu_host->chip);
695 	ebu_nand_disable(&ebu_host->chip);
696 	ebu_dma_cleanup(ebu_host);
697 	clk_disable_unprepare(ebu_host->clk);
698 
699 	return 0;
700 }
701 
702 static const struct of_device_id ebu_nand_match[] = {
703 	{ .compatible = "intel,nand-controller" },
704 	{ .compatible = "intel,lgm-ebunand" },
705 	{}
706 };
707 MODULE_DEVICE_TABLE(of, ebu_nand_match);
708 
709 static struct platform_driver ebu_nand_driver = {
710 	.probe = ebu_nand_probe,
711 	.remove = ebu_nand_remove,
712 	.driver = {
713 		.name = "intel-nand-controller",
714 		.of_match_table = ebu_nand_match,
715 	},
716 
717 };
718 module_platform_driver(ebu_nand_driver);
719 
720 MODULE_LICENSE("GPL v2");
721 MODULE_AUTHOR("Vadivel Murugan R <vadivel.muruganx.ramuthevar@intel.com>");
722 MODULE_DESCRIPTION("Intel's LGM External Bus NAND Controller driver");
723