1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) STMicroelectronics 2018
4  * Author: Christophe Kerello <christophe.kerello@st.com>
5  */
6 
7 #include <linux/bitfield.h>
8 #include <linux/clk.h>
9 #include <linux/dmaengine.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/errno.h>
12 #include <linux/interrupt.h>
13 #include <linux/iopoll.h>
14 #include <linux/mfd/syscon.h>
15 #include <linux/module.h>
16 #include <linux/mtd/rawnand.h>
17 #include <linux/of_address.h>
18 #include <linux/pinctrl/consumer.h>
19 #include <linux/platform_device.h>
20 #include <linux/regmap.h>
21 #include <linux/reset.h>
22 
23 /* Bad block marker length */
24 #define FMC2_BBM_LEN			2
25 
26 /* ECC step size */
27 #define FMC2_ECC_STEP_SIZE		512
28 
29 /* BCHDSRx registers length */
30 #define FMC2_BCHDSRS_LEN		20
31 
32 /* HECCR length */
33 #define FMC2_HECCR_LEN			4
34 
35 /* Max requests done for a 8k nand page size */
36 #define FMC2_MAX_SG			16
37 
38 /* Max chip enable */
39 #define FMC2_MAX_CE			2
40 
41 /* Max ECC buffer length */
42 #define FMC2_MAX_ECC_BUF_LEN		(FMC2_BCHDSRS_LEN * FMC2_MAX_SG)
43 
44 #define FMC2_TIMEOUT_MS			5000
45 
46 /* Timings */
47 #define FMC2_THIZ			1
48 #define FMC2_TIO			8000
49 #define FMC2_TSYNC			3000
50 #define FMC2_PCR_TIMING_MASK		0xf
51 #define FMC2_PMEM_PATT_TIMING_MASK	0xff
52 
53 /* FMC2 Controller Registers */
54 #define FMC2_BCR1			0x0
55 #define FMC2_PCR			0x80
56 #define FMC2_SR				0x84
57 #define FMC2_PMEM			0x88
58 #define FMC2_PATT			0x8c
59 #define FMC2_HECCR			0x94
60 #define FMC2_ISR			0x184
61 #define FMC2_ICR			0x188
62 #define FMC2_CSQCR			0x200
63 #define FMC2_CSQCFGR1			0x204
64 #define FMC2_CSQCFGR2			0x208
65 #define FMC2_CSQCFGR3			0x20c
66 #define FMC2_CSQAR1			0x210
67 #define FMC2_CSQAR2			0x214
68 #define FMC2_CSQIER			0x220
69 #define FMC2_CSQISR			0x224
70 #define FMC2_CSQICR			0x228
71 #define FMC2_CSQEMSR			0x230
72 #define FMC2_BCHIER			0x250
73 #define FMC2_BCHISR			0x254
74 #define FMC2_BCHICR			0x258
75 #define FMC2_BCHPBR1			0x260
76 #define FMC2_BCHPBR2			0x264
77 #define FMC2_BCHPBR3			0x268
78 #define FMC2_BCHPBR4			0x26c
79 #define FMC2_BCHDSR0			0x27c
80 #define FMC2_BCHDSR1			0x280
81 #define FMC2_BCHDSR2			0x284
82 #define FMC2_BCHDSR3			0x288
83 #define FMC2_BCHDSR4			0x28c
84 
85 /* Register: FMC2_BCR1 */
86 #define FMC2_BCR1_FMC2EN		BIT(31)
87 
88 /* Register: FMC2_PCR */
89 #define FMC2_PCR_PWAITEN		BIT(1)
90 #define FMC2_PCR_PBKEN			BIT(2)
91 #define FMC2_PCR_PWID			GENMASK(5, 4)
92 #define FMC2_PCR_PWID_BUSWIDTH_8	0
93 #define FMC2_PCR_PWID_BUSWIDTH_16	1
94 #define FMC2_PCR_ECCEN			BIT(6)
95 #define FMC2_PCR_ECCALG			BIT(8)
96 #define FMC2_PCR_TCLR			GENMASK(12, 9)
97 #define FMC2_PCR_TCLR_DEFAULT		0xf
98 #define FMC2_PCR_TAR			GENMASK(16, 13)
99 #define FMC2_PCR_TAR_DEFAULT		0xf
100 #define FMC2_PCR_ECCSS			GENMASK(19, 17)
101 #define FMC2_PCR_ECCSS_512		1
102 #define FMC2_PCR_ECCSS_2048		3
103 #define FMC2_PCR_BCHECC			BIT(24)
104 #define FMC2_PCR_WEN			BIT(25)
105 
106 /* Register: FMC2_SR */
107 #define FMC2_SR_NWRF			BIT(6)
108 
109 /* Register: FMC2_PMEM */
110 #define FMC2_PMEM_MEMSET		GENMASK(7, 0)
111 #define FMC2_PMEM_MEMWAIT		GENMASK(15, 8)
112 #define FMC2_PMEM_MEMHOLD		GENMASK(23, 16)
113 #define FMC2_PMEM_MEMHIZ		GENMASK(31, 24)
114 #define FMC2_PMEM_DEFAULT		0x0a0a0a0a
115 
116 /* Register: FMC2_PATT */
117 #define FMC2_PATT_ATTSET		GENMASK(7, 0)
118 #define FMC2_PATT_ATTWAIT		GENMASK(15, 8)
119 #define FMC2_PATT_ATTHOLD		GENMASK(23, 16)
120 #define FMC2_PATT_ATTHIZ		GENMASK(31, 24)
121 #define FMC2_PATT_DEFAULT		0x0a0a0a0a
122 
123 /* Register: FMC2_ISR */
124 #define FMC2_ISR_IHLF			BIT(1)
125 
126 /* Register: FMC2_ICR */
127 #define FMC2_ICR_CIHLF			BIT(1)
128 
129 /* Register: FMC2_CSQCR */
130 #define FMC2_CSQCR_CSQSTART		BIT(0)
131 
132 /* Register: FMC2_CSQCFGR1 */
133 #define FMC2_CSQCFGR1_CMD2EN		BIT(1)
134 #define FMC2_CSQCFGR1_DMADEN		BIT(2)
135 #define FMC2_CSQCFGR1_ACYNBR		GENMASK(6, 4)
136 #define FMC2_CSQCFGR1_CMD1		GENMASK(15, 8)
137 #define FMC2_CSQCFGR1_CMD2		GENMASK(23, 16)
138 #define FMC2_CSQCFGR1_CMD1T		BIT(24)
139 #define FMC2_CSQCFGR1_CMD2T		BIT(25)
140 
141 /* Register: FMC2_CSQCFGR2 */
142 #define FMC2_CSQCFGR2_SQSDTEN		BIT(0)
143 #define FMC2_CSQCFGR2_RCMD2EN		BIT(1)
144 #define FMC2_CSQCFGR2_DMASEN		BIT(2)
145 #define FMC2_CSQCFGR2_RCMD1		GENMASK(15, 8)
146 #define FMC2_CSQCFGR2_RCMD2		GENMASK(23, 16)
147 #define FMC2_CSQCFGR2_RCMD1T		BIT(24)
148 #define FMC2_CSQCFGR2_RCMD2T		BIT(25)
149 
150 /* Register: FMC2_CSQCFGR3 */
151 #define FMC2_CSQCFGR3_SNBR		GENMASK(13, 8)
152 #define FMC2_CSQCFGR3_AC1T		BIT(16)
153 #define FMC2_CSQCFGR3_AC2T		BIT(17)
154 #define FMC2_CSQCFGR3_AC3T		BIT(18)
155 #define FMC2_CSQCFGR3_AC4T		BIT(19)
156 #define FMC2_CSQCFGR3_AC5T		BIT(20)
157 #define FMC2_CSQCFGR3_SDT		BIT(21)
158 #define FMC2_CSQCFGR3_RAC1T		BIT(22)
159 #define FMC2_CSQCFGR3_RAC2T		BIT(23)
160 
161 /* Register: FMC2_CSQCAR1 */
162 #define FMC2_CSQCAR1_ADDC1		GENMASK(7, 0)
163 #define FMC2_CSQCAR1_ADDC2		GENMASK(15, 8)
164 #define FMC2_CSQCAR1_ADDC3		GENMASK(23, 16)
165 #define FMC2_CSQCAR1_ADDC4		GENMASK(31, 24)
166 
167 /* Register: FMC2_CSQCAR2 */
168 #define FMC2_CSQCAR2_ADDC5		GENMASK(7, 0)
169 #define FMC2_CSQCAR2_NANDCEN		GENMASK(11, 10)
170 #define FMC2_CSQCAR2_SAO		GENMASK(31, 16)
171 
172 /* Register: FMC2_CSQIER */
173 #define FMC2_CSQIER_TCIE		BIT(0)
174 
175 /* Register: FMC2_CSQICR */
176 #define FMC2_CSQICR_CLEAR_IRQ		GENMASK(4, 0)
177 
178 /* Register: FMC2_CSQEMSR */
179 #define FMC2_CSQEMSR_SEM		GENMASK(15, 0)
180 
181 /* Register: FMC2_BCHIER */
182 #define FMC2_BCHIER_DERIE		BIT(1)
183 #define FMC2_BCHIER_EPBRIE		BIT(4)
184 
185 /* Register: FMC2_BCHICR */
186 #define FMC2_BCHICR_CLEAR_IRQ		GENMASK(4, 0)
187 
188 /* Register: FMC2_BCHDSR0 */
189 #define FMC2_BCHDSR0_DUE		BIT(0)
190 #define FMC2_BCHDSR0_DEF		BIT(1)
191 #define FMC2_BCHDSR0_DEN		GENMASK(7, 4)
192 
193 /* Register: FMC2_BCHDSR1 */
194 #define FMC2_BCHDSR1_EBP1		GENMASK(12, 0)
195 #define FMC2_BCHDSR1_EBP2		GENMASK(28, 16)
196 
197 /* Register: FMC2_BCHDSR2 */
198 #define FMC2_BCHDSR2_EBP3		GENMASK(12, 0)
199 #define FMC2_BCHDSR2_EBP4		GENMASK(28, 16)
200 
201 /* Register: FMC2_BCHDSR3 */
202 #define FMC2_BCHDSR3_EBP5		GENMASK(12, 0)
203 #define FMC2_BCHDSR3_EBP6		GENMASK(28, 16)
204 
205 /* Register: FMC2_BCHDSR4 */
206 #define FMC2_BCHDSR4_EBP7		GENMASK(12, 0)
207 #define FMC2_BCHDSR4_EBP8		GENMASK(28, 16)
208 
209 enum stm32_fmc2_ecc {
210 	FMC2_ECC_HAM = 1,
211 	FMC2_ECC_BCH4 = 4,
212 	FMC2_ECC_BCH8 = 8
213 };
214 
215 enum stm32_fmc2_irq_state {
216 	FMC2_IRQ_UNKNOWN = 0,
217 	FMC2_IRQ_BCH,
218 	FMC2_IRQ_SEQ
219 };
220 
221 struct stm32_fmc2_timings {
222 	u8 tclr;
223 	u8 tar;
224 	u8 thiz;
225 	u8 twait;
226 	u8 thold_mem;
227 	u8 tset_mem;
228 	u8 thold_att;
229 	u8 tset_att;
230 };
231 
232 struct stm32_fmc2_nand {
233 	struct nand_chip chip;
234 	struct stm32_fmc2_timings timings;
235 	int ncs;
236 	int cs_used[FMC2_MAX_CE];
237 };
238 
239 static inline struct stm32_fmc2_nand *to_fmc2_nand(struct nand_chip *chip)
240 {
241 	return container_of(chip, struct stm32_fmc2_nand, chip);
242 }
243 
244 struct stm32_fmc2_nfc {
245 	struct nand_controller base;
246 	struct stm32_fmc2_nand nand;
247 	struct device *dev;
248 	struct device *cdev;
249 	struct regmap *regmap;
250 	void __iomem *data_base[FMC2_MAX_CE];
251 	void __iomem *cmd_base[FMC2_MAX_CE];
252 	void __iomem *addr_base[FMC2_MAX_CE];
253 	phys_addr_t io_phys_addr;
254 	phys_addr_t data_phys_addr[FMC2_MAX_CE];
255 	struct clk *clk;
256 	u8 irq_state;
257 
258 	struct dma_chan *dma_tx_ch;
259 	struct dma_chan *dma_rx_ch;
260 	struct dma_chan *dma_ecc_ch;
261 	struct sg_table dma_data_sg;
262 	struct sg_table dma_ecc_sg;
263 	u8 *ecc_buf;
264 	int dma_ecc_len;
265 
266 	struct completion complete;
267 	struct completion dma_data_complete;
268 	struct completion dma_ecc_complete;
269 
270 	u8 cs_assigned;
271 	int cs_sel;
272 };
273 
274 static inline struct stm32_fmc2_nfc *to_stm32_nfc(struct nand_controller *base)
275 {
276 	return container_of(base, struct stm32_fmc2_nfc, base);
277 }
278 
279 static void stm32_fmc2_nfc_timings_init(struct nand_chip *chip)
280 {
281 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
282 	struct stm32_fmc2_nand *nand = to_fmc2_nand(chip);
283 	struct stm32_fmc2_timings *timings = &nand->timings;
284 	u32 pmem, patt;
285 
286 	/* Set tclr/tar timings */
287 	regmap_update_bits(nfc->regmap, FMC2_PCR,
288 			   FMC2_PCR_TCLR | FMC2_PCR_TAR,
289 			   FIELD_PREP(FMC2_PCR_TCLR, timings->tclr) |
290 			   FIELD_PREP(FMC2_PCR_TAR, timings->tar));
291 
292 	/* Set tset/twait/thold/thiz timings in common bank */
293 	pmem = FIELD_PREP(FMC2_PMEM_MEMSET, timings->tset_mem);
294 	pmem |= FIELD_PREP(FMC2_PMEM_MEMWAIT, timings->twait);
295 	pmem |= FIELD_PREP(FMC2_PMEM_MEMHOLD, timings->thold_mem);
296 	pmem |= FIELD_PREP(FMC2_PMEM_MEMHIZ, timings->thiz);
297 	regmap_write(nfc->regmap, FMC2_PMEM, pmem);
298 
299 	/* Set tset/twait/thold/thiz timings in attribut bank */
300 	patt = FIELD_PREP(FMC2_PATT_ATTSET, timings->tset_att);
301 	patt |= FIELD_PREP(FMC2_PATT_ATTWAIT, timings->twait);
302 	patt |= FIELD_PREP(FMC2_PATT_ATTHOLD, timings->thold_att);
303 	patt |= FIELD_PREP(FMC2_PATT_ATTHIZ, timings->thiz);
304 	regmap_write(nfc->regmap, FMC2_PATT, patt);
305 }
306 
307 static void stm32_fmc2_nfc_setup(struct nand_chip *chip)
308 {
309 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
310 	u32 pcr = 0, pcr_mask;
311 
312 	/* Configure ECC algorithm (default configuration is Hamming) */
313 	pcr_mask = FMC2_PCR_ECCALG;
314 	pcr_mask |= FMC2_PCR_BCHECC;
315 	if (chip->ecc.strength == FMC2_ECC_BCH8) {
316 		pcr |= FMC2_PCR_ECCALG;
317 		pcr |= FMC2_PCR_BCHECC;
318 	} else if (chip->ecc.strength == FMC2_ECC_BCH4) {
319 		pcr |= FMC2_PCR_ECCALG;
320 	}
321 
322 	/* Set buswidth */
323 	pcr_mask |= FMC2_PCR_PWID;
324 	if (chip->options & NAND_BUSWIDTH_16)
325 		pcr |= FIELD_PREP(FMC2_PCR_PWID, FMC2_PCR_PWID_BUSWIDTH_16);
326 
327 	/* Set ECC sector size */
328 	pcr_mask |= FMC2_PCR_ECCSS;
329 	pcr |= FIELD_PREP(FMC2_PCR_ECCSS, FMC2_PCR_ECCSS_512);
330 
331 	regmap_update_bits(nfc->regmap, FMC2_PCR, pcr_mask, pcr);
332 }
333 
334 static int stm32_fmc2_nfc_select_chip(struct nand_chip *chip, int chipnr)
335 {
336 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
337 	struct stm32_fmc2_nand *nand = to_fmc2_nand(chip);
338 	struct dma_slave_config dma_cfg;
339 	int ret;
340 
341 	if (nand->cs_used[chipnr] == nfc->cs_sel)
342 		return 0;
343 
344 	nfc->cs_sel = nand->cs_used[chipnr];
345 	stm32_fmc2_nfc_setup(chip);
346 	stm32_fmc2_nfc_timings_init(chip);
347 
348 	if (nfc->dma_tx_ch && nfc->dma_rx_ch) {
349 		memset(&dma_cfg, 0, sizeof(dma_cfg));
350 		dma_cfg.src_addr = nfc->data_phys_addr[nfc->cs_sel];
351 		dma_cfg.dst_addr = nfc->data_phys_addr[nfc->cs_sel];
352 		dma_cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
353 		dma_cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
354 		dma_cfg.src_maxburst = 32;
355 		dma_cfg.dst_maxburst = 32;
356 
357 		ret = dmaengine_slave_config(nfc->dma_tx_ch, &dma_cfg);
358 		if (ret) {
359 			dev_err(nfc->dev, "tx DMA engine slave config failed\n");
360 			return ret;
361 		}
362 
363 		ret = dmaengine_slave_config(nfc->dma_rx_ch, &dma_cfg);
364 		if (ret) {
365 			dev_err(nfc->dev, "rx DMA engine slave config failed\n");
366 			return ret;
367 		}
368 	}
369 
370 	if (nfc->dma_ecc_ch) {
371 		/*
372 		 * Hamming: we read HECCR register
373 		 * BCH4/BCH8: we read BCHDSRSx registers
374 		 */
375 		memset(&dma_cfg, 0, sizeof(dma_cfg));
376 		dma_cfg.src_addr = nfc->io_phys_addr;
377 		dma_cfg.src_addr += chip->ecc.strength == FMC2_ECC_HAM ?
378 				    FMC2_HECCR : FMC2_BCHDSR0;
379 		dma_cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
380 
381 		ret = dmaengine_slave_config(nfc->dma_ecc_ch, &dma_cfg);
382 		if (ret) {
383 			dev_err(nfc->dev, "ECC DMA engine slave config failed\n");
384 			return ret;
385 		}
386 
387 		/* Calculate ECC length needed for one sector */
388 		nfc->dma_ecc_len = chip->ecc.strength == FMC2_ECC_HAM ?
389 				   FMC2_HECCR_LEN : FMC2_BCHDSRS_LEN;
390 	}
391 
392 	return 0;
393 }
394 
395 static void stm32_fmc2_nfc_set_buswidth_16(struct stm32_fmc2_nfc *nfc, bool set)
396 {
397 	u32 pcr;
398 
399 	pcr = set ? FIELD_PREP(FMC2_PCR_PWID, FMC2_PCR_PWID_BUSWIDTH_16) :
400 		    FIELD_PREP(FMC2_PCR_PWID, FMC2_PCR_PWID_BUSWIDTH_8);
401 
402 	regmap_update_bits(nfc->regmap, FMC2_PCR, FMC2_PCR_PWID, pcr);
403 }
404 
405 static void stm32_fmc2_nfc_set_ecc(struct stm32_fmc2_nfc *nfc, bool enable)
406 {
407 	regmap_update_bits(nfc->regmap, FMC2_PCR, FMC2_PCR_ECCEN,
408 			   enable ? FMC2_PCR_ECCEN : 0);
409 }
410 
411 static void stm32_fmc2_nfc_enable_seq_irq(struct stm32_fmc2_nfc *nfc)
412 {
413 	nfc->irq_state = FMC2_IRQ_SEQ;
414 
415 	regmap_update_bits(nfc->regmap, FMC2_CSQIER,
416 			   FMC2_CSQIER_TCIE, FMC2_CSQIER_TCIE);
417 }
418 
419 static void stm32_fmc2_nfc_disable_seq_irq(struct stm32_fmc2_nfc *nfc)
420 {
421 	regmap_update_bits(nfc->regmap, FMC2_CSQIER, FMC2_CSQIER_TCIE, 0);
422 
423 	nfc->irq_state = FMC2_IRQ_UNKNOWN;
424 }
425 
426 static void stm32_fmc2_nfc_clear_seq_irq(struct stm32_fmc2_nfc *nfc)
427 {
428 	regmap_write(nfc->regmap, FMC2_CSQICR, FMC2_CSQICR_CLEAR_IRQ);
429 }
430 
431 static void stm32_fmc2_nfc_enable_bch_irq(struct stm32_fmc2_nfc *nfc, int mode)
432 {
433 	nfc->irq_state = FMC2_IRQ_BCH;
434 
435 	if (mode == NAND_ECC_WRITE)
436 		regmap_update_bits(nfc->regmap, FMC2_BCHIER,
437 				   FMC2_BCHIER_EPBRIE, FMC2_BCHIER_EPBRIE);
438 	else
439 		regmap_update_bits(nfc->regmap, FMC2_BCHIER,
440 				   FMC2_BCHIER_DERIE, FMC2_BCHIER_DERIE);
441 }
442 
443 static void stm32_fmc2_nfc_disable_bch_irq(struct stm32_fmc2_nfc *nfc)
444 {
445 	regmap_update_bits(nfc->regmap, FMC2_BCHIER,
446 			   FMC2_BCHIER_DERIE | FMC2_BCHIER_EPBRIE, 0);
447 
448 	nfc->irq_state = FMC2_IRQ_UNKNOWN;
449 }
450 
451 static void stm32_fmc2_nfc_clear_bch_irq(struct stm32_fmc2_nfc *nfc)
452 {
453 	regmap_write(nfc->regmap, FMC2_BCHICR, FMC2_BCHICR_CLEAR_IRQ);
454 }
455 
456 /*
457  * Enable ECC logic and reset syndrome/parity bits previously calculated
458  * Syndrome/parity bits is cleared by setting the ECCEN bit to 0
459  */
460 static void stm32_fmc2_nfc_hwctl(struct nand_chip *chip, int mode)
461 {
462 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
463 
464 	stm32_fmc2_nfc_set_ecc(nfc, false);
465 
466 	if (chip->ecc.strength != FMC2_ECC_HAM) {
467 		regmap_update_bits(nfc->regmap, FMC2_PCR, FMC2_PCR_WEN,
468 				   mode == NAND_ECC_WRITE ? FMC2_PCR_WEN : 0);
469 
470 		reinit_completion(&nfc->complete);
471 		stm32_fmc2_nfc_clear_bch_irq(nfc);
472 		stm32_fmc2_nfc_enable_bch_irq(nfc, mode);
473 	}
474 
475 	stm32_fmc2_nfc_set_ecc(nfc, true);
476 }
477 
478 /*
479  * ECC Hamming calculation
480  * ECC is 3 bytes for 512 bytes of data (supports error correction up to
481  * max of 1-bit)
482  */
483 static void stm32_fmc2_nfc_ham_set_ecc(const u32 ecc_sta, u8 *ecc)
484 {
485 	ecc[0] = ecc_sta;
486 	ecc[1] = ecc_sta >> 8;
487 	ecc[2] = ecc_sta >> 16;
488 }
489 
490 static int stm32_fmc2_nfc_ham_calculate(struct nand_chip *chip, const u8 *data,
491 					u8 *ecc)
492 {
493 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
494 	u32 sr, heccr;
495 	int ret;
496 
497 	ret = regmap_read_poll_timeout(nfc->regmap, FMC2_SR, sr,
498 				       sr & FMC2_SR_NWRF, 1,
499 				       1000 * FMC2_TIMEOUT_MS);
500 	if (ret) {
501 		dev_err(nfc->dev, "ham timeout\n");
502 		return ret;
503 	}
504 
505 	regmap_read(nfc->regmap, FMC2_HECCR, &heccr);
506 	stm32_fmc2_nfc_ham_set_ecc(heccr, ecc);
507 	stm32_fmc2_nfc_set_ecc(nfc, false);
508 
509 	return 0;
510 }
511 
512 static int stm32_fmc2_nfc_ham_correct(struct nand_chip *chip, u8 *dat,
513 				      u8 *read_ecc, u8 *calc_ecc)
514 {
515 	u8 bit_position = 0, b0, b1, b2;
516 	u32 byte_addr = 0, b;
517 	u32 i, shifting = 1;
518 
519 	/* Indicate which bit and byte is faulty (if any) */
520 	b0 = read_ecc[0] ^ calc_ecc[0];
521 	b1 = read_ecc[1] ^ calc_ecc[1];
522 	b2 = read_ecc[2] ^ calc_ecc[2];
523 	b = b0 | (b1 << 8) | (b2 << 16);
524 
525 	/* No errors */
526 	if (likely(!b))
527 		return 0;
528 
529 	/* Calculate bit position */
530 	for (i = 0; i < 3; i++) {
531 		switch (b % 4) {
532 		case 2:
533 			bit_position += shifting;
534 		case 1:
535 			break;
536 		default:
537 			return -EBADMSG;
538 		}
539 		shifting <<= 1;
540 		b >>= 2;
541 	}
542 
543 	/* Calculate byte position */
544 	shifting = 1;
545 	for (i = 0; i < 9; i++) {
546 		switch (b % 4) {
547 		case 2:
548 			byte_addr += shifting;
549 		case 1:
550 			break;
551 		default:
552 			return -EBADMSG;
553 		}
554 		shifting <<= 1;
555 		b >>= 2;
556 	}
557 
558 	/* Flip the bit */
559 	dat[byte_addr] ^= (1 << bit_position);
560 
561 	return 1;
562 }
563 
564 /*
565  * ECC BCH calculation and correction
566  * ECC is 7/13 bytes for 512 bytes of data (supports error correction up to
567  * max of 4-bit/8-bit)
568  */
569 static int stm32_fmc2_nfc_bch_calculate(struct nand_chip *chip, const u8 *data,
570 					u8 *ecc)
571 {
572 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
573 	u32 bchpbr;
574 
575 	/* Wait until the BCH code is ready */
576 	if (!wait_for_completion_timeout(&nfc->complete,
577 					 msecs_to_jiffies(FMC2_TIMEOUT_MS))) {
578 		dev_err(nfc->dev, "bch timeout\n");
579 		stm32_fmc2_nfc_disable_bch_irq(nfc);
580 		return -ETIMEDOUT;
581 	}
582 
583 	/* Read parity bits */
584 	regmap_read(nfc->regmap, FMC2_BCHPBR1, &bchpbr);
585 	ecc[0] = bchpbr;
586 	ecc[1] = bchpbr >> 8;
587 	ecc[2] = bchpbr >> 16;
588 	ecc[3] = bchpbr >> 24;
589 
590 	regmap_read(nfc->regmap, FMC2_BCHPBR2, &bchpbr);
591 	ecc[4] = bchpbr;
592 	ecc[5] = bchpbr >> 8;
593 	ecc[6] = bchpbr >> 16;
594 
595 	if (chip->ecc.strength == FMC2_ECC_BCH8) {
596 		ecc[7] = bchpbr >> 24;
597 
598 		regmap_read(nfc->regmap, FMC2_BCHPBR3, &bchpbr);
599 		ecc[8] = bchpbr;
600 		ecc[9] = bchpbr >> 8;
601 		ecc[10] = bchpbr >> 16;
602 		ecc[11] = bchpbr >> 24;
603 
604 		regmap_read(nfc->regmap, FMC2_BCHPBR4, &bchpbr);
605 		ecc[12] = bchpbr;
606 	}
607 
608 	stm32_fmc2_nfc_set_ecc(nfc, false);
609 
610 	return 0;
611 }
612 
613 static int stm32_fmc2_nfc_bch_decode(int eccsize, u8 *dat, u32 *ecc_sta)
614 {
615 	u32 bchdsr0 = ecc_sta[0];
616 	u32 bchdsr1 = ecc_sta[1];
617 	u32 bchdsr2 = ecc_sta[2];
618 	u32 bchdsr3 = ecc_sta[3];
619 	u32 bchdsr4 = ecc_sta[4];
620 	u16 pos[8];
621 	int i, den;
622 	unsigned int nb_errs = 0;
623 
624 	/* No errors found */
625 	if (likely(!(bchdsr0 & FMC2_BCHDSR0_DEF)))
626 		return 0;
627 
628 	/* Too many errors detected */
629 	if (unlikely(bchdsr0 & FMC2_BCHDSR0_DUE))
630 		return -EBADMSG;
631 
632 	pos[0] = FIELD_GET(FMC2_BCHDSR1_EBP1, bchdsr1);
633 	pos[1] = FIELD_GET(FMC2_BCHDSR1_EBP2, bchdsr1);
634 	pos[2] = FIELD_GET(FMC2_BCHDSR2_EBP3, bchdsr2);
635 	pos[3] = FIELD_GET(FMC2_BCHDSR2_EBP4, bchdsr2);
636 	pos[4] = FIELD_GET(FMC2_BCHDSR3_EBP5, bchdsr3);
637 	pos[5] = FIELD_GET(FMC2_BCHDSR3_EBP6, bchdsr3);
638 	pos[6] = FIELD_GET(FMC2_BCHDSR4_EBP7, bchdsr4);
639 	pos[7] = FIELD_GET(FMC2_BCHDSR4_EBP8, bchdsr4);
640 
641 	den = FIELD_GET(FMC2_BCHDSR0_DEN, bchdsr0);
642 	for (i = 0; i < den; i++) {
643 		if (pos[i] < eccsize * 8) {
644 			change_bit(pos[i], (unsigned long *)dat);
645 			nb_errs++;
646 		}
647 	}
648 
649 	return nb_errs;
650 }
651 
652 static int stm32_fmc2_nfc_bch_correct(struct nand_chip *chip, u8 *dat,
653 				      u8 *read_ecc, u8 *calc_ecc)
654 {
655 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
656 	u32 ecc_sta[5];
657 
658 	/* Wait until the decoding error is ready */
659 	if (!wait_for_completion_timeout(&nfc->complete,
660 					 msecs_to_jiffies(FMC2_TIMEOUT_MS))) {
661 		dev_err(nfc->dev, "bch timeout\n");
662 		stm32_fmc2_nfc_disable_bch_irq(nfc);
663 		return -ETIMEDOUT;
664 	}
665 
666 	regmap_bulk_read(nfc->regmap, FMC2_BCHDSR0, ecc_sta, 5);
667 
668 	stm32_fmc2_nfc_set_ecc(nfc, false);
669 
670 	return stm32_fmc2_nfc_bch_decode(chip->ecc.size, dat, ecc_sta);
671 }
672 
673 static int stm32_fmc2_nfc_read_page(struct nand_chip *chip, u8 *buf,
674 				    int oob_required, int page)
675 {
676 	struct mtd_info *mtd = nand_to_mtd(chip);
677 	int ret, i, s, stat, eccsize = chip->ecc.size;
678 	int eccbytes = chip->ecc.bytes;
679 	int eccsteps = chip->ecc.steps;
680 	int eccstrength = chip->ecc.strength;
681 	u8 *p = buf;
682 	u8 *ecc_calc = chip->ecc.calc_buf;
683 	u8 *ecc_code = chip->ecc.code_buf;
684 	unsigned int max_bitflips = 0;
685 
686 	ret = nand_read_page_op(chip, page, 0, NULL, 0);
687 	if (ret)
688 		return ret;
689 
690 	for (i = mtd->writesize + FMC2_BBM_LEN, s = 0; s < eccsteps;
691 	     s++, i += eccbytes, p += eccsize) {
692 		chip->ecc.hwctl(chip, NAND_ECC_READ);
693 
694 		/* Read the nand page sector (512 bytes) */
695 		ret = nand_change_read_column_op(chip, s * eccsize, p,
696 						 eccsize, false);
697 		if (ret)
698 			return ret;
699 
700 		/* Read the corresponding ECC bytes */
701 		ret = nand_change_read_column_op(chip, i, ecc_code,
702 						 eccbytes, false);
703 		if (ret)
704 			return ret;
705 
706 		/* Correct the data */
707 		stat = chip->ecc.correct(chip, p, ecc_code, ecc_calc);
708 		if (stat == -EBADMSG)
709 			/* Check for empty pages with bitflips */
710 			stat = nand_check_erased_ecc_chunk(p, eccsize,
711 							   ecc_code, eccbytes,
712 							   NULL, 0,
713 							   eccstrength);
714 
715 		if (stat < 0) {
716 			mtd->ecc_stats.failed++;
717 		} else {
718 			mtd->ecc_stats.corrected += stat;
719 			max_bitflips = max_t(unsigned int, max_bitflips, stat);
720 		}
721 	}
722 
723 	/* Read oob */
724 	if (oob_required) {
725 		ret = nand_change_read_column_op(chip, mtd->writesize,
726 						 chip->oob_poi, mtd->oobsize,
727 						 false);
728 		if (ret)
729 			return ret;
730 	}
731 
732 	return max_bitflips;
733 }
734 
735 /* Sequencer read/write configuration */
736 static void stm32_fmc2_nfc_rw_page_init(struct nand_chip *chip, int page,
737 					int raw, bool write_data)
738 {
739 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
740 	struct mtd_info *mtd = nand_to_mtd(chip);
741 	u32 ecc_offset = mtd->writesize + FMC2_BBM_LEN;
742 	/*
743 	 * cfg[0] => csqcfgr1, cfg[1] => csqcfgr2, cfg[2] => csqcfgr3
744 	 * cfg[3] => csqar1, cfg[4] => csqar2
745 	 */
746 	u32 cfg[5];
747 
748 	regmap_update_bits(nfc->regmap, FMC2_PCR, FMC2_PCR_WEN,
749 			   write_data ? FMC2_PCR_WEN : 0);
750 
751 	/*
752 	 * - Set Program Page/Page Read command
753 	 * - Enable DMA request data
754 	 * - Set timings
755 	 */
756 	cfg[0] = FMC2_CSQCFGR1_DMADEN | FMC2_CSQCFGR1_CMD1T;
757 	if (write_data)
758 		cfg[0] |= FIELD_PREP(FMC2_CSQCFGR1_CMD1, NAND_CMD_SEQIN);
759 	else
760 		cfg[0] |= FIELD_PREP(FMC2_CSQCFGR1_CMD1, NAND_CMD_READ0) |
761 			  FMC2_CSQCFGR1_CMD2EN |
762 			  FIELD_PREP(FMC2_CSQCFGR1_CMD2, NAND_CMD_READSTART) |
763 			  FMC2_CSQCFGR1_CMD2T;
764 
765 	/*
766 	 * - Set Random Data Input/Random Data Read command
767 	 * - Enable the sequencer to access the Spare data area
768 	 * - Enable  DMA request status decoding for read
769 	 * - Set timings
770 	 */
771 	if (write_data)
772 		cfg[1] = FIELD_PREP(FMC2_CSQCFGR2_RCMD1, NAND_CMD_RNDIN);
773 	else
774 		cfg[1] = FIELD_PREP(FMC2_CSQCFGR2_RCMD1, NAND_CMD_RNDOUT) |
775 			 FMC2_CSQCFGR2_RCMD2EN |
776 			 FIELD_PREP(FMC2_CSQCFGR2_RCMD2, NAND_CMD_RNDOUTSTART) |
777 			 FMC2_CSQCFGR2_RCMD1T |
778 			 FMC2_CSQCFGR2_RCMD2T;
779 	if (!raw) {
780 		cfg[1] |= write_data ? 0 : FMC2_CSQCFGR2_DMASEN;
781 		cfg[1] |= FMC2_CSQCFGR2_SQSDTEN;
782 	}
783 
784 	/*
785 	 * - Set the number of sectors to be written
786 	 * - Set timings
787 	 */
788 	cfg[2] = FIELD_PREP(FMC2_CSQCFGR3_SNBR, chip->ecc.steps - 1);
789 	if (write_data) {
790 		cfg[2] |= FMC2_CSQCFGR3_RAC2T;
791 		if (chip->options & NAND_ROW_ADDR_3)
792 			cfg[2] |= FMC2_CSQCFGR3_AC5T;
793 		else
794 			cfg[2] |= FMC2_CSQCFGR3_AC4T;
795 	}
796 
797 	/*
798 	 * Set the fourth first address cycles
799 	 * Byte 1 and byte 2 => column, we start at 0x0
800 	 * Byte 3 and byte 4 => page
801 	 */
802 	cfg[3] = FIELD_PREP(FMC2_CSQCAR1_ADDC3, page);
803 	cfg[3] |= FIELD_PREP(FMC2_CSQCAR1_ADDC4, page >> 8);
804 
805 	/*
806 	 * - Set chip enable number
807 	 * - Set ECC byte offset in the spare area
808 	 * - Calculate the number of address cycles to be issued
809 	 * - Set byte 5 of address cycle if needed
810 	 */
811 	cfg[4] = FIELD_PREP(FMC2_CSQCAR2_NANDCEN, nfc->cs_sel);
812 	if (chip->options & NAND_BUSWIDTH_16)
813 		cfg[4] |= FIELD_PREP(FMC2_CSQCAR2_SAO, ecc_offset >> 1);
814 	else
815 		cfg[4] |= FIELD_PREP(FMC2_CSQCAR2_SAO, ecc_offset);
816 	if (chip->options & NAND_ROW_ADDR_3) {
817 		cfg[0] |= FIELD_PREP(FMC2_CSQCFGR1_ACYNBR, 5);
818 		cfg[4] |= FIELD_PREP(FMC2_CSQCAR2_ADDC5, page >> 16);
819 	} else {
820 		cfg[0] |= FIELD_PREP(FMC2_CSQCFGR1_ACYNBR, 4);
821 	}
822 
823 	regmap_bulk_write(nfc->regmap, FMC2_CSQCFGR1, cfg, 5);
824 }
825 
826 static void stm32_fmc2_nfc_dma_callback(void *arg)
827 {
828 	complete((struct completion *)arg);
829 }
830 
831 /* Read/write data from/to a page */
832 static int stm32_fmc2_nfc_xfer(struct nand_chip *chip, const u8 *buf,
833 			       int raw, bool write_data)
834 {
835 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
836 	struct dma_async_tx_descriptor *desc_data, *desc_ecc;
837 	struct scatterlist *sg;
838 	struct dma_chan *dma_ch = nfc->dma_rx_ch;
839 	enum dma_data_direction dma_data_dir = DMA_FROM_DEVICE;
840 	enum dma_transfer_direction dma_transfer_dir = DMA_DEV_TO_MEM;
841 	int eccsteps = chip->ecc.steps;
842 	int eccsize = chip->ecc.size;
843 	unsigned long timeout = msecs_to_jiffies(FMC2_TIMEOUT_MS);
844 	const u8 *p = buf;
845 	int s, ret;
846 
847 	/* Configure DMA data */
848 	if (write_data) {
849 		dma_data_dir = DMA_TO_DEVICE;
850 		dma_transfer_dir = DMA_MEM_TO_DEV;
851 		dma_ch = nfc->dma_tx_ch;
852 	}
853 
854 	for_each_sg(nfc->dma_data_sg.sgl, sg, eccsteps, s) {
855 		sg_set_buf(sg, p, eccsize);
856 		p += eccsize;
857 	}
858 
859 	ret = dma_map_sg(nfc->dev, nfc->dma_data_sg.sgl,
860 			 eccsteps, dma_data_dir);
861 	if (ret < 0)
862 		return ret;
863 
864 	desc_data = dmaengine_prep_slave_sg(dma_ch, nfc->dma_data_sg.sgl,
865 					    eccsteps, dma_transfer_dir,
866 					    DMA_PREP_INTERRUPT);
867 	if (!desc_data) {
868 		ret = -ENOMEM;
869 		goto err_unmap_data;
870 	}
871 
872 	reinit_completion(&nfc->dma_data_complete);
873 	reinit_completion(&nfc->complete);
874 	desc_data->callback = stm32_fmc2_nfc_dma_callback;
875 	desc_data->callback_param = &nfc->dma_data_complete;
876 	ret = dma_submit_error(dmaengine_submit(desc_data));
877 	if (ret)
878 		goto err_unmap_data;
879 
880 	dma_async_issue_pending(dma_ch);
881 
882 	if (!write_data && !raw) {
883 		/* Configure DMA ECC status */
884 		p = nfc->ecc_buf;
885 		for_each_sg(nfc->dma_ecc_sg.sgl, sg, eccsteps, s) {
886 			sg_set_buf(sg, p, nfc->dma_ecc_len);
887 			p += nfc->dma_ecc_len;
888 		}
889 
890 		ret = dma_map_sg(nfc->dev, nfc->dma_ecc_sg.sgl,
891 				 eccsteps, dma_data_dir);
892 		if (ret < 0)
893 			goto err_unmap_data;
894 
895 		desc_ecc = dmaengine_prep_slave_sg(nfc->dma_ecc_ch,
896 						   nfc->dma_ecc_sg.sgl,
897 						   eccsteps, dma_transfer_dir,
898 						   DMA_PREP_INTERRUPT);
899 		if (!desc_ecc) {
900 			ret = -ENOMEM;
901 			goto err_unmap_ecc;
902 		}
903 
904 		reinit_completion(&nfc->dma_ecc_complete);
905 		desc_ecc->callback = stm32_fmc2_nfc_dma_callback;
906 		desc_ecc->callback_param = &nfc->dma_ecc_complete;
907 		ret = dma_submit_error(dmaengine_submit(desc_ecc));
908 		if (ret)
909 			goto err_unmap_ecc;
910 
911 		dma_async_issue_pending(nfc->dma_ecc_ch);
912 	}
913 
914 	stm32_fmc2_nfc_clear_seq_irq(nfc);
915 	stm32_fmc2_nfc_enable_seq_irq(nfc);
916 
917 	/* Start the transfer */
918 	regmap_update_bits(nfc->regmap, FMC2_CSQCR,
919 			   FMC2_CSQCR_CSQSTART, FMC2_CSQCR_CSQSTART);
920 
921 	/* Wait end of sequencer transfer */
922 	if (!wait_for_completion_timeout(&nfc->complete, timeout)) {
923 		dev_err(nfc->dev, "seq timeout\n");
924 		stm32_fmc2_nfc_disable_seq_irq(nfc);
925 		dmaengine_terminate_all(dma_ch);
926 		if (!write_data && !raw)
927 			dmaengine_terminate_all(nfc->dma_ecc_ch);
928 		ret = -ETIMEDOUT;
929 		goto err_unmap_ecc;
930 	}
931 
932 	/* Wait DMA data transfer completion */
933 	if (!wait_for_completion_timeout(&nfc->dma_data_complete, timeout)) {
934 		dev_err(nfc->dev, "data DMA timeout\n");
935 		dmaengine_terminate_all(dma_ch);
936 		ret = -ETIMEDOUT;
937 	}
938 
939 	/* Wait DMA ECC transfer completion */
940 	if (!write_data && !raw) {
941 		if (!wait_for_completion_timeout(&nfc->dma_ecc_complete,
942 						 timeout)) {
943 			dev_err(nfc->dev, "ECC DMA timeout\n");
944 			dmaengine_terminate_all(nfc->dma_ecc_ch);
945 			ret = -ETIMEDOUT;
946 		}
947 	}
948 
949 err_unmap_ecc:
950 	if (!write_data && !raw)
951 		dma_unmap_sg(nfc->dev, nfc->dma_ecc_sg.sgl,
952 			     eccsteps, dma_data_dir);
953 
954 err_unmap_data:
955 	dma_unmap_sg(nfc->dev, nfc->dma_data_sg.sgl, eccsteps, dma_data_dir);
956 
957 	return ret;
958 }
959 
960 static int stm32_fmc2_nfc_seq_write(struct nand_chip *chip, const u8 *buf,
961 				    int oob_required, int page, int raw)
962 {
963 	struct mtd_info *mtd = nand_to_mtd(chip);
964 	int ret;
965 
966 	/* Configure the sequencer */
967 	stm32_fmc2_nfc_rw_page_init(chip, page, raw, true);
968 
969 	/* Write the page */
970 	ret = stm32_fmc2_nfc_xfer(chip, buf, raw, true);
971 	if (ret)
972 		return ret;
973 
974 	/* Write oob */
975 	if (oob_required) {
976 		ret = nand_change_write_column_op(chip, mtd->writesize,
977 						  chip->oob_poi, mtd->oobsize,
978 						  false);
979 		if (ret)
980 			return ret;
981 	}
982 
983 	return nand_prog_page_end_op(chip);
984 }
985 
986 static int stm32_fmc2_nfc_seq_write_page(struct nand_chip *chip, const u8 *buf,
987 					 int oob_required, int page)
988 {
989 	int ret;
990 
991 	ret = stm32_fmc2_nfc_select_chip(chip, chip->cur_cs);
992 	if (ret)
993 		return ret;
994 
995 	return stm32_fmc2_nfc_seq_write(chip, buf, oob_required, page, false);
996 }
997 
998 static int stm32_fmc2_nfc_seq_write_page_raw(struct nand_chip *chip,
999 					     const u8 *buf, int oob_required,
1000 					     int page)
1001 {
1002 	int ret;
1003 
1004 	ret = stm32_fmc2_nfc_select_chip(chip, chip->cur_cs);
1005 	if (ret)
1006 		return ret;
1007 
1008 	return stm32_fmc2_nfc_seq_write(chip, buf, oob_required, page, true);
1009 }
1010 
1011 /* Get a status indicating which sectors have errors */
1012 static u16 stm32_fmc2_nfc_get_mapping_status(struct stm32_fmc2_nfc *nfc)
1013 {
1014 	u32 csqemsr;
1015 
1016 	regmap_read(nfc->regmap, FMC2_CSQEMSR, &csqemsr);
1017 
1018 	return FIELD_GET(FMC2_CSQEMSR_SEM, csqemsr);
1019 }
1020 
1021 static int stm32_fmc2_nfc_seq_correct(struct nand_chip *chip, u8 *dat,
1022 				      u8 *read_ecc, u8 *calc_ecc)
1023 {
1024 	struct mtd_info *mtd = nand_to_mtd(chip);
1025 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
1026 	int eccbytes = chip->ecc.bytes;
1027 	int eccsteps = chip->ecc.steps;
1028 	int eccstrength = chip->ecc.strength;
1029 	int i, s, eccsize = chip->ecc.size;
1030 	u32 *ecc_sta = (u32 *)nfc->ecc_buf;
1031 	u16 sta_map = stm32_fmc2_nfc_get_mapping_status(nfc);
1032 	unsigned int max_bitflips = 0;
1033 
1034 	for (i = 0, s = 0; s < eccsteps; s++, i += eccbytes, dat += eccsize) {
1035 		int stat = 0;
1036 
1037 		if (eccstrength == FMC2_ECC_HAM) {
1038 			/* Ecc_sta = FMC2_HECCR */
1039 			if (sta_map & BIT(s)) {
1040 				stm32_fmc2_nfc_ham_set_ecc(*ecc_sta,
1041 							   &calc_ecc[i]);
1042 				stat = stm32_fmc2_nfc_ham_correct(chip, dat,
1043 								  &read_ecc[i],
1044 								  &calc_ecc[i]);
1045 			}
1046 			ecc_sta++;
1047 		} else {
1048 			/*
1049 			 * Ecc_sta[0] = FMC2_BCHDSR0
1050 			 * Ecc_sta[1] = FMC2_BCHDSR1
1051 			 * Ecc_sta[2] = FMC2_BCHDSR2
1052 			 * Ecc_sta[3] = FMC2_BCHDSR3
1053 			 * Ecc_sta[4] = FMC2_BCHDSR4
1054 			 */
1055 			if (sta_map & BIT(s))
1056 				stat = stm32_fmc2_nfc_bch_decode(eccsize, dat,
1057 								 ecc_sta);
1058 			ecc_sta += 5;
1059 		}
1060 
1061 		if (stat == -EBADMSG)
1062 			/* Check for empty pages with bitflips */
1063 			stat = nand_check_erased_ecc_chunk(dat, eccsize,
1064 							   &read_ecc[i],
1065 							   eccbytes,
1066 							   NULL, 0,
1067 							   eccstrength);
1068 
1069 		if (stat < 0) {
1070 			mtd->ecc_stats.failed++;
1071 		} else {
1072 			mtd->ecc_stats.corrected += stat;
1073 			max_bitflips = max_t(unsigned int, max_bitflips, stat);
1074 		}
1075 	}
1076 
1077 	return max_bitflips;
1078 }
1079 
1080 static int stm32_fmc2_nfc_seq_read_page(struct nand_chip *chip, u8 *buf,
1081 					int oob_required, int page)
1082 {
1083 	struct mtd_info *mtd = nand_to_mtd(chip);
1084 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
1085 	u8 *ecc_calc = chip->ecc.calc_buf;
1086 	u8 *ecc_code = chip->ecc.code_buf;
1087 	u16 sta_map;
1088 	int ret;
1089 
1090 	ret = stm32_fmc2_nfc_select_chip(chip, chip->cur_cs);
1091 	if (ret)
1092 		return ret;
1093 
1094 	/* Configure the sequencer */
1095 	stm32_fmc2_nfc_rw_page_init(chip, page, 0, false);
1096 
1097 	/* Read the page */
1098 	ret = stm32_fmc2_nfc_xfer(chip, buf, 0, false);
1099 	if (ret)
1100 		return ret;
1101 
1102 	sta_map = stm32_fmc2_nfc_get_mapping_status(nfc);
1103 
1104 	/* Check if errors happen */
1105 	if (likely(!sta_map)) {
1106 		if (oob_required)
1107 			return nand_change_read_column_op(chip, mtd->writesize,
1108 							  chip->oob_poi,
1109 							  mtd->oobsize, false);
1110 
1111 		return 0;
1112 	}
1113 
1114 	/* Read oob */
1115 	ret = nand_change_read_column_op(chip, mtd->writesize,
1116 					 chip->oob_poi, mtd->oobsize, false);
1117 	if (ret)
1118 		return ret;
1119 
1120 	ret = mtd_ooblayout_get_eccbytes(mtd, ecc_code, chip->oob_poi, 0,
1121 					 chip->ecc.total);
1122 	if (ret)
1123 		return ret;
1124 
1125 	/* Correct data */
1126 	return chip->ecc.correct(chip, buf, ecc_code, ecc_calc);
1127 }
1128 
1129 static int stm32_fmc2_nfc_seq_read_page_raw(struct nand_chip *chip, u8 *buf,
1130 					    int oob_required, int page)
1131 {
1132 	struct mtd_info *mtd = nand_to_mtd(chip);
1133 	int ret;
1134 
1135 	ret = stm32_fmc2_nfc_select_chip(chip, chip->cur_cs);
1136 	if (ret)
1137 		return ret;
1138 
1139 	/* Configure the sequencer */
1140 	stm32_fmc2_nfc_rw_page_init(chip, page, 1, false);
1141 
1142 	/* Read the page */
1143 	ret = stm32_fmc2_nfc_xfer(chip, buf, 1, false);
1144 	if (ret)
1145 		return ret;
1146 
1147 	/* Read oob */
1148 	if (oob_required)
1149 		return nand_change_read_column_op(chip, mtd->writesize,
1150 						  chip->oob_poi, mtd->oobsize,
1151 						  false);
1152 
1153 	return 0;
1154 }
1155 
1156 static irqreturn_t stm32_fmc2_nfc_irq(int irq, void *dev_id)
1157 {
1158 	struct stm32_fmc2_nfc *nfc = (struct stm32_fmc2_nfc *)dev_id;
1159 
1160 	if (nfc->irq_state == FMC2_IRQ_SEQ)
1161 		/* Sequencer is used */
1162 		stm32_fmc2_nfc_disable_seq_irq(nfc);
1163 	else if (nfc->irq_state == FMC2_IRQ_BCH)
1164 		/* BCH is used */
1165 		stm32_fmc2_nfc_disable_bch_irq(nfc);
1166 
1167 	complete(&nfc->complete);
1168 
1169 	return IRQ_HANDLED;
1170 }
1171 
1172 static void stm32_fmc2_nfc_read_data(struct nand_chip *chip, void *buf,
1173 				     unsigned int len, bool force_8bit)
1174 {
1175 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
1176 	void __iomem *io_addr_r = nfc->data_base[nfc->cs_sel];
1177 
1178 	if (force_8bit && chip->options & NAND_BUSWIDTH_16)
1179 		/* Reconfigure bus width to 8-bit */
1180 		stm32_fmc2_nfc_set_buswidth_16(nfc, false);
1181 
1182 	if (!IS_ALIGNED((uintptr_t)buf, sizeof(u32))) {
1183 		if (!IS_ALIGNED((uintptr_t)buf, sizeof(u16)) && len) {
1184 			*(u8 *)buf = readb_relaxed(io_addr_r);
1185 			buf += sizeof(u8);
1186 			len -= sizeof(u8);
1187 		}
1188 
1189 		if (!IS_ALIGNED((uintptr_t)buf, sizeof(u32)) &&
1190 		    len >= sizeof(u16)) {
1191 			*(u16 *)buf = readw_relaxed(io_addr_r);
1192 			buf += sizeof(u16);
1193 			len -= sizeof(u16);
1194 		}
1195 	}
1196 
1197 	/* Buf is aligned */
1198 	while (len >= sizeof(u32)) {
1199 		*(u32 *)buf = readl_relaxed(io_addr_r);
1200 		buf += sizeof(u32);
1201 		len -= sizeof(u32);
1202 	}
1203 
1204 	/* Read remaining bytes */
1205 	if (len >= sizeof(u16)) {
1206 		*(u16 *)buf = readw_relaxed(io_addr_r);
1207 		buf += sizeof(u16);
1208 		len -= sizeof(u16);
1209 	}
1210 
1211 	if (len)
1212 		*(u8 *)buf = readb_relaxed(io_addr_r);
1213 
1214 	if (force_8bit && chip->options & NAND_BUSWIDTH_16)
1215 		/* Reconfigure bus width to 16-bit */
1216 		stm32_fmc2_nfc_set_buswidth_16(nfc, true);
1217 }
1218 
1219 static void stm32_fmc2_nfc_write_data(struct nand_chip *chip, const void *buf,
1220 				      unsigned int len, bool force_8bit)
1221 {
1222 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
1223 	void __iomem *io_addr_w = nfc->data_base[nfc->cs_sel];
1224 
1225 	if (force_8bit && chip->options & NAND_BUSWIDTH_16)
1226 		/* Reconfigure bus width to 8-bit */
1227 		stm32_fmc2_nfc_set_buswidth_16(nfc, false);
1228 
1229 	if (!IS_ALIGNED((uintptr_t)buf, sizeof(u32))) {
1230 		if (!IS_ALIGNED((uintptr_t)buf, sizeof(u16)) && len) {
1231 			writeb_relaxed(*(u8 *)buf, io_addr_w);
1232 			buf += sizeof(u8);
1233 			len -= sizeof(u8);
1234 		}
1235 
1236 		if (!IS_ALIGNED((uintptr_t)buf, sizeof(u32)) &&
1237 		    len >= sizeof(u16)) {
1238 			writew_relaxed(*(u16 *)buf, io_addr_w);
1239 			buf += sizeof(u16);
1240 			len -= sizeof(u16);
1241 		}
1242 	}
1243 
1244 	/* Buf is aligned */
1245 	while (len >= sizeof(u32)) {
1246 		writel_relaxed(*(u32 *)buf, io_addr_w);
1247 		buf += sizeof(u32);
1248 		len -= sizeof(u32);
1249 	}
1250 
1251 	/* Write remaining bytes */
1252 	if (len >= sizeof(u16)) {
1253 		writew_relaxed(*(u16 *)buf, io_addr_w);
1254 		buf += sizeof(u16);
1255 		len -= sizeof(u16);
1256 	}
1257 
1258 	if (len)
1259 		writeb_relaxed(*(u8 *)buf, io_addr_w);
1260 
1261 	if (force_8bit && chip->options & NAND_BUSWIDTH_16)
1262 		/* Reconfigure bus width to 16-bit */
1263 		stm32_fmc2_nfc_set_buswidth_16(nfc, true);
1264 }
1265 
1266 static int stm32_fmc2_nfc_waitrdy(struct nand_chip *chip,
1267 				  unsigned long timeout_ms)
1268 {
1269 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
1270 	const struct nand_sdr_timings *timings;
1271 	u32 isr, sr;
1272 
1273 	/* Check if there is no pending requests to the NAND flash */
1274 	if (regmap_read_poll_timeout(nfc->regmap, FMC2_SR, sr,
1275 				     sr & FMC2_SR_NWRF, 1,
1276 				     1000 * FMC2_TIMEOUT_MS))
1277 		dev_warn(nfc->dev, "Waitrdy timeout\n");
1278 
1279 	/* Wait tWB before R/B# signal is low */
1280 	timings = nand_get_sdr_timings(nand_get_interface_config(chip));
1281 	ndelay(PSEC_TO_NSEC(timings->tWB_max));
1282 
1283 	/* R/B# signal is low, clear high level flag */
1284 	regmap_write(nfc->regmap, FMC2_ICR, FMC2_ICR_CIHLF);
1285 
1286 	/* Wait R/B# signal is high */
1287 	return regmap_read_poll_timeout(nfc->regmap, FMC2_ISR, isr,
1288 					isr & FMC2_ISR_IHLF, 5,
1289 					1000 * FMC2_TIMEOUT_MS);
1290 }
1291 
1292 static int stm32_fmc2_nfc_exec_op(struct nand_chip *chip,
1293 				  const struct nand_operation *op,
1294 				  bool check_only)
1295 {
1296 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
1297 	const struct nand_op_instr *instr = NULL;
1298 	unsigned int op_id, i, timeout;
1299 	int ret;
1300 
1301 	if (check_only)
1302 		return 0;
1303 
1304 	ret = stm32_fmc2_nfc_select_chip(chip, op->cs);
1305 	if (ret)
1306 		return ret;
1307 
1308 	for (op_id = 0; op_id < op->ninstrs; op_id++) {
1309 		instr = &op->instrs[op_id];
1310 
1311 		switch (instr->type) {
1312 		case NAND_OP_CMD_INSTR:
1313 			writeb_relaxed(instr->ctx.cmd.opcode,
1314 				       nfc->cmd_base[nfc->cs_sel]);
1315 			break;
1316 
1317 		case NAND_OP_ADDR_INSTR:
1318 			for (i = 0; i < instr->ctx.addr.naddrs; i++)
1319 				writeb_relaxed(instr->ctx.addr.addrs[i],
1320 					       nfc->addr_base[nfc->cs_sel]);
1321 			break;
1322 
1323 		case NAND_OP_DATA_IN_INSTR:
1324 			stm32_fmc2_nfc_read_data(chip, instr->ctx.data.buf.in,
1325 						 instr->ctx.data.len,
1326 						 instr->ctx.data.force_8bit);
1327 			break;
1328 
1329 		case NAND_OP_DATA_OUT_INSTR:
1330 			stm32_fmc2_nfc_write_data(chip, instr->ctx.data.buf.out,
1331 						  instr->ctx.data.len,
1332 						  instr->ctx.data.force_8bit);
1333 			break;
1334 
1335 		case NAND_OP_WAITRDY_INSTR:
1336 			timeout = instr->ctx.waitrdy.timeout_ms;
1337 			ret = stm32_fmc2_nfc_waitrdy(chip, timeout);
1338 			break;
1339 		}
1340 	}
1341 
1342 	return ret;
1343 }
1344 
1345 static void stm32_fmc2_nfc_init(struct stm32_fmc2_nfc *nfc)
1346 {
1347 	u32 pcr;
1348 
1349 	regmap_read(nfc->regmap, FMC2_PCR, &pcr);
1350 
1351 	/* Set CS used to undefined */
1352 	nfc->cs_sel = -1;
1353 
1354 	/* Enable wait feature and nand flash memory bank */
1355 	pcr |= FMC2_PCR_PWAITEN;
1356 	pcr |= FMC2_PCR_PBKEN;
1357 
1358 	/* Set buswidth to 8 bits mode for identification */
1359 	pcr &= ~FMC2_PCR_PWID;
1360 
1361 	/* ECC logic is disabled */
1362 	pcr &= ~FMC2_PCR_ECCEN;
1363 
1364 	/* Default mode */
1365 	pcr &= ~FMC2_PCR_ECCALG;
1366 	pcr &= ~FMC2_PCR_BCHECC;
1367 	pcr &= ~FMC2_PCR_WEN;
1368 
1369 	/* Set default ECC sector size */
1370 	pcr &= ~FMC2_PCR_ECCSS;
1371 	pcr |= FIELD_PREP(FMC2_PCR_ECCSS, FMC2_PCR_ECCSS_2048);
1372 
1373 	/* Set default tclr/tar timings */
1374 	pcr &= ~FMC2_PCR_TCLR;
1375 	pcr |= FIELD_PREP(FMC2_PCR_TCLR, FMC2_PCR_TCLR_DEFAULT);
1376 	pcr &= ~FMC2_PCR_TAR;
1377 	pcr |= FIELD_PREP(FMC2_PCR_TAR, FMC2_PCR_TAR_DEFAULT);
1378 
1379 	/* Enable FMC2 controller */
1380 	if (nfc->dev == nfc->cdev)
1381 		regmap_update_bits(nfc->regmap, FMC2_BCR1,
1382 				   FMC2_BCR1_FMC2EN, FMC2_BCR1_FMC2EN);
1383 
1384 	regmap_write(nfc->regmap, FMC2_PCR, pcr);
1385 	regmap_write(nfc->regmap, FMC2_PMEM, FMC2_PMEM_DEFAULT);
1386 	regmap_write(nfc->regmap, FMC2_PATT, FMC2_PATT_DEFAULT);
1387 }
1388 
1389 static void stm32_fmc2_nfc_calc_timings(struct nand_chip *chip,
1390 					const struct nand_sdr_timings *sdrt)
1391 {
1392 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
1393 	struct stm32_fmc2_nand *nand = to_fmc2_nand(chip);
1394 	struct stm32_fmc2_timings *tims = &nand->timings;
1395 	unsigned long hclk = clk_get_rate(nfc->clk);
1396 	unsigned long hclkp = NSEC_PER_SEC / (hclk / 1000);
1397 	unsigned long timing, tar, tclr, thiz, twait;
1398 	unsigned long tset_mem, tset_att, thold_mem, thold_att;
1399 
1400 	tar = max_t(unsigned long, hclkp, sdrt->tAR_min);
1401 	timing = DIV_ROUND_UP(tar, hclkp) - 1;
1402 	tims->tar = min_t(unsigned long, timing, FMC2_PCR_TIMING_MASK);
1403 
1404 	tclr = max_t(unsigned long, hclkp, sdrt->tCLR_min);
1405 	timing = DIV_ROUND_UP(tclr, hclkp) - 1;
1406 	tims->tclr = min_t(unsigned long, timing, FMC2_PCR_TIMING_MASK);
1407 
1408 	tims->thiz = FMC2_THIZ;
1409 	thiz = (tims->thiz + 1) * hclkp;
1410 
1411 	/*
1412 	 * tWAIT > tRP
1413 	 * tWAIT > tWP
1414 	 * tWAIT > tREA + tIO
1415 	 */
1416 	twait = max_t(unsigned long, hclkp, sdrt->tRP_min);
1417 	twait = max_t(unsigned long, twait, sdrt->tWP_min);
1418 	twait = max_t(unsigned long, twait, sdrt->tREA_max + FMC2_TIO);
1419 	timing = DIV_ROUND_UP(twait, hclkp);
1420 	tims->twait = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);
1421 
1422 	/*
1423 	 * tSETUP_MEM > tCS - tWAIT
1424 	 * tSETUP_MEM > tALS - tWAIT
1425 	 * tSETUP_MEM > tDS - (tWAIT - tHIZ)
1426 	 */
1427 	tset_mem = hclkp;
1428 	if (sdrt->tCS_min > twait && (tset_mem < sdrt->tCS_min - twait))
1429 		tset_mem = sdrt->tCS_min - twait;
1430 	if (sdrt->tALS_min > twait && (tset_mem < sdrt->tALS_min - twait))
1431 		tset_mem = sdrt->tALS_min - twait;
1432 	if (twait > thiz && (sdrt->tDS_min > twait - thiz) &&
1433 	    (tset_mem < sdrt->tDS_min - (twait - thiz)))
1434 		tset_mem = sdrt->tDS_min - (twait - thiz);
1435 	timing = DIV_ROUND_UP(tset_mem, hclkp);
1436 	tims->tset_mem = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);
1437 
1438 	/*
1439 	 * tHOLD_MEM > tCH
1440 	 * tHOLD_MEM > tREH - tSETUP_MEM
1441 	 * tHOLD_MEM > max(tRC, tWC) - (tSETUP_MEM + tWAIT)
1442 	 */
1443 	thold_mem = max_t(unsigned long, hclkp, sdrt->tCH_min);
1444 	if (sdrt->tREH_min > tset_mem &&
1445 	    (thold_mem < sdrt->tREH_min - tset_mem))
1446 		thold_mem = sdrt->tREH_min - tset_mem;
1447 	if ((sdrt->tRC_min > tset_mem + twait) &&
1448 	    (thold_mem < sdrt->tRC_min - (tset_mem + twait)))
1449 		thold_mem = sdrt->tRC_min - (tset_mem + twait);
1450 	if ((sdrt->tWC_min > tset_mem + twait) &&
1451 	    (thold_mem < sdrt->tWC_min - (tset_mem + twait)))
1452 		thold_mem = sdrt->tWC_min - (tset_mem + twait);
1453 	timing = DIV_ROUND_UP(thold_mem, hclkp);
1454 	tims->thold_mem = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);
1455 
1456 	/*
1457 	 * tSETUP_ATT > tCS - tWAIT
1458 	 * tSETUP_ATT > tCLS - tWAIT
1459 	 * tSETUP_ATT > tALS - tWAIT
1460 	 * tSETUP_ATT > tRHW - tHOLD_MEM
1461 	 * tSETUP_ATT > tDS - (tWAIT - tHIZ)
1462 	 */
1463 	tset_att = hclkp;
1464 	if (sdrt->tCS_min > twait && (tset_att < sdrt->tCS_min - twait))
1465 		tset_att = sdrt->tCS_min - twait;
1466 	if (sdrt->tCLS_min > twait && (tset_att < sdrt->tCLS_min - twait))
1467 		tset_att = sdrt->tCLS_min - twait;
1468 	if (sdrt->tALS_min > twait && (tset_att < sdrt->tALS_min - twait))
1469 		tset_att = sdrt->tALS_min - twait;
1470 	if (sdrt->tRHW_min > thold_mem &&
1471 	    (tset_att < sdrt->tRHW_min - thold_mem))
1472 		tset_att = sdrt->tRHW_min - thold_mem;
1473 	if (twait > thiz && (sdrt->tDS_min > twait - thiz) &&
1474 	    (tset_att < sdrt->tDS_min - (twait - thiz)))
1475 		tset_att = sdrt->tDS_min - (twait - thiz);
1476 	timing = DIV_ROUND_UP(tset_att, hclkp);
1477 	tims->tset_att = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);
1478 
1479 	/*
1480 	 * tHOLD_ATT > tALH
1481 	 * tHOLD_ATT > tCH
1482 	 * tHOLD_ATT > tCLH
1483 	 * tHOLD_ATT > tCOH
1484 	 * tHOLD_ATT > tDH
1485 	 * tHOLD_ATT > tWB + tIO + tSYNC - tSETUP_MEM
1486 	 * tHOLD_ATT > tADL - tSETUP_MEM
1487 	 * tHOLD_ATT > tWH - tSETUP_MEM
1488 	 * tHOLD_ATT > tWHR - tSETUP_MEM
1489 	 * tHOLD_ATT > tRC - (tSETUP_ATT + tWAIT)
1490 	 * tHOLD_ATT > tWC - (tSETUP_ATT + tWAIT)
1491 	 */
1492 	thold_att = max_t(unsigned long, hclkp, sdrt->tALH_min);
1493 	thold_att = max_t(unsigned long, thold_att, sdrt->tCH_min);
1494 	thold_att = max_t(unsigned long, thold_att, sdrt->tCLH_min);
1495 	thold_att = max_t(unsigned long, thold_att, sdrt->tCOH_min);
1496 	thold_att = max_t(unsigned long, thold_att, sdrt->tDH_min);
1497 	if ((sdrt->tWB_max + FMC2_TIO + FMC2_TSYNC > tset_mem) &&
1498 	    (thold_att < sdrt->tWB_max + FMC2_TIO + FMC2_TSYNC - tset_mem))
1499 		thold_att = sdrt->tWB_max + FMC2_TIO + FMC2_TSYNC - tset_mem;
1500 	if (sdrt->tADL_min > tset_mem &&
1501 	    (thold_att < sdrt->tADL_min - tset_mem))
1502 		thold_att = sdrt->tADL_min - tset_mem;
1503 	if (sdrt->tWH_min > tset_mem &&
1504 	    (thold_att < sdrt->tWH_min - tset_mem))
1505 		thold_att = sdrt->tWH_min - tset_mem;
1506 	if (sdrt->tWHR_min > tset_mem &&
1507 	    (thold_att < sdrt->tWHR_min - tset_mem))
1508 		thold_att = sdrt->tWHR_min - tset_mem;
1509 	if ((sdrt->tRC_min > tset_att + twait) &&
1510 	    (thold_att < sdrt->tRC_min - (tset_att + twait)))
1511 		thold_att = sdrt->tRC_min - (tset_att + twait);
1512 	if ((sdrt->tWC_min > tset_att + twait) &&
1513 	    (thold_att < sdrt->tWC_min - (tset_att + twait)))
1514 		thold_att = sdrt->tWC_min - (tset_att + twait);
1515 	timing = DIV_ROUND_UP(thold_att, hclkp);
1516 	tims->thold_att = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);
1517 }
1518 
1519 static int stm32_fmc2_nfc_setup_interface(struct nand_chip *chip, int chipnr,
1520 					  const struct nand_interface_config *conf)
1521 {
1522 	const struct nand_sdr_timings *sdrt;
1523 
1524 	sdrt = nand_get_sdr_timings(conf);
1525 	if (IS_ERR(sdrt))
1526 		return PTR_ERR(sdrt);
1527 
1528 	if (chipnr == NAND_DATA_IFACE_CHECK_ONLY)
1529 		return 0;
1530 
1531 	stm32_fmc2_nfc_calc_timings(chip, sdrt);
1532 	stm32_fmc2_nfc_timings_init(chip);
1533 
1534 	return 0;
1535 }
1536 
1537 static int stm32_fmc2_nfc_dma_setup(struct stm32_fmc2_nfc *nfc)
1538 {
1539 	int ret = 0;
1540 
1541 	nfc->dma_tx_ch = dma_request_chan(nfc->dev, "tx");
1542 	if (IS_ERR(nfc->dma_tx_ch)) {
1543 		ret = PTR_ERR(nfc->dma_tx_ch);
1544 		if (ret != -ENODEV && ret != -EPROBE_DEFER)
1545 			dev_err(nfc->dev,
1546 				"failed to request tx DMA channel: %d\n", ret);
1547 		nfc->dma_tx_ch = NULL;
1548 		goto err_dma;
1549 	}
1550 
1551 	nfc->dma_rx_ch = dma_request_chan(nfc->dev, "rx");
1552 	if (IS_ERR(nfc->dma_rx_ch)) {
1553 		ret = PTR_ERR(nfc->dma_rx_ch);
1554 		if (ret != -ENODEV && ret != -EPROBE_DEFER)
1555 			dev_err(nfc->dev,
1556 				"failed to request rx DMA channel: %d\n", ret);
1557 		nfc->dma_rx_ch = NULL;
1558 		goto err_dma;
1559 	}
1560 
1561 	nfc->dma_ecc_ch = dma_request_chan(nfc->dev, "ecc");
1562 	if (IS_ERR(nfc->dma_ecc_ch)) {
1563 		ret = PTR_ERR(nfc->dma_ecc_ch);
1564 		if (ret != -ENODEV && ret != -EPROBE_DEFER)
1565 			dev_err(nfc->dev,
1566 				"failed to request ecc DMA channel: %d\n", ret);
1567 		nfc->dma_ecc_ch = NULL;
1568 		goto err_dma;
1569 	}
1570 
1571 	ret = sg_alloc_table(&nfc->dma_ecc_sg, FMC2_MAX_SG, GFP_KERNEL);
1572 	if (ret)
1573 		return ret;
1574 
1575 	/* Allocate a buffer to store ECC status registers */
1576 	nfc->ecc_buf = devm_kzalloc(nfc->dev, FMC2_MAX_ECC_BUF_LEN, GFP_KERNEL);
1577 	if (!nfc->ecc_buf)
1578 		return -ENOMEM;
1579 
1580 	ret = sg_alloc_table(&nfc->dma_data_sg, FMC2_MAX_SG, GFP_KERNEL);
1581 	if (ret)
1582 		return ret;
1583 
1584 	init_completion(&nfc->dma_data_complete);
1585 	init_completion(&nfc->dma_ecc_complete);
1586 
1587 	return 0;
1588 
1589 err_dma:
1590 	if (ret == -ENODEV) {
1591 		dev_warn(nfc->dev,
1592 			 "DMAs not defined in the DT, polling mode is used\n");
1593 		ret = 0;
1594 	}
1595 
1596 	return ret;
1597 }
1598 
1599 static void stm32_fmc2_nfc_nand_callbacks_setup(struct nand_chip *chip)
1600 {
1601 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
1602 
1603 	/*
1604 	 * Specific callbacks to read/write a page depending on
1605 	 * the mode (polling/sequencer) and the algo used (Hamming, BCH).
1606 	 */
1607 	if (nfc->dma_tx_ch && nfc->dma_rx_ch && nfc->dma_ecc_ch) {
1608 		/* DMA => use sequencer mode callbacks */
1609 		chip->ecc.correct = stm32_fmc2_nfc_seq_correct;
1610 		chip->ecc.write_page = stm32_fmc2_nfc_seq_write_page;
1611 		chip->ecc.read_page = stm32_fmc2_nfc_seq_read_page;
1612 		chip->ecc.write_page_raw = stm32_fmc2_nfc_seq_write_page_raw;
1613 		chip->ecc.read_page_raw = stm32_fmc2_nfc_seq_read_page_raw;
1614 	} else {
1615 		/* No DMA => use polling mode callbacks */
1616 		chip->ecc.hwctl = stm32_fmc2_nfc_hwctl;
1617 		if (chip->ecc.strength == FMC2_ECC_HAM) {
1618 			/* Hamming is used */
1619 			chip->ecc.calculate = stm32_fmc2_nfc_ham_calculate;
1620 			chip->ecc.correct = stm32_fmc2_nfc_ham_correct;
1621 			chip->ecc.options |= NAND_ECC_GENERIC_ERASED_CHECK;
1622 		} else {
1623 			/* BCH is used */
1624 			chip->ecc.calculate = stm32_fmc2_nfc_bch_calculate;
1625 			chip->ecc.correct = stm32_fmc2_nfc_bch_correct;
1626 			chip->ecc.read_page = stm32_fmc2_nfc_read_page;
1627 		}
1628 	}
1629 
1630 	/* Specific configurations depending on the algo used */
1631 	if (chip->ecc.strength == FMC2_ECC_HAM)
1632 		chip->ecc.bytes = chip->options & NAND_BUSWIDTH_16 ? 4 : 3;
1633 	else if (chip->ecc.strength == FMC2_ECC_BCH8)
1634 		chip->ecc.bytes = chip->options & NAND_BUSWIDTH_16 ? 14 : 13;
1635 	else
1636 		chip->ecc.bytes = chip->options & NAND_BUSWIDTH_16 ? 8 : 7;
1637 }
1638 
1639 static int stm32_fmc2_nfc_ooblayout_ecc(struct mtd_info *mtd, int section,
1640 					struct mtd_oob_region *oobregion)
1641 {
1642 	struct nand_chip *chip = mtd_to_nand(mtd);
1643 	struct nand_ecc_ctrl *ecc = &chip->ecc;
1644 
1645 	if (section)
1646 		return -ERANGE;
1647 
1648 	oobregion->length = ecc->total;
1649 	oobregion->offset = FMC2_BBM_LEN;
1650 
1651 	return 0;
1652 }
1653 
1654 static int stm32_fmc2_nfc_ooblayout_free(struct mtd_info *mtd, int section,
1655 					 struct mtd_oob_region *oobregion)
1656 {
1657 	struct nand_chip *chip = mtd_to_nand(mtd);
1658 	struct nand_ecc_ctrl *ecc = &chip->ecc;
1659 
1660 	if (section)
1661 		return -ERANGE;
1662 
1663 	oobregion->length = mtd->oobsize - ecc->total - FMC2_BBM_LEN;
1664 	oobregion->offset = ecc->total + FMC2_BBM_LEN;
1665 
1666 	return 0;
1667 }
1668 
1669 static const struct mtd_ooblayout_ops stm32_fmc2_nfc_ooblayout_ops = {
1670 	.ecc = stm32_fmc2_nfc_ooblayout_ecc,
1671 	.free = stm32_fmc2_nfc_ooblayout_free,
1672 };
1673 
1674 static int stm32_fmc2_nfc_calc_ecc_bytes(int step_size, int strength)
1675 {
1676 	/* Hamming */
1677 	if (strength == FMC2_ECC_HAM)
1678 		return 4;
1679 
1680 	/* BCH8 */
1681 	if (strength == FMC2_ECC_BCH8)
1682 		return 14;
1683 
1684 	/* BCH4 */
1685 	return 8;
1686 }
1687 
1688 NAND_ECC_CAPS_SINGLE(stm32_fmc2_nfc_ecc_caps, stm32_fmc2_nfc_calc_ecc_bytes,
1689 		     FMC2_ECC_STEP_SIZE,
1690 		     FMC2_ECC_HAM, FMC2_ECC_BCH4, FMC2_ECC_BCH8);
1691 
1692 static int stm32_fmc2_nfc_attach_chip(struct nand_chip *chip)
1693 {
1694 	struct stm32_fmc2_nfc *nfc = to_stm32_nfc(chip->controller);
1695 	struct mtd_info *mtd = nand_to_mtd(chip);
1696 	int ret;
1697 
1698 	/*
1699 	 * Only NAND_ECC_ENGINE_TYPE_ON_HOST mode is actually supported
1700 	 * Hamming => ecc.strength = 1
1701 	 * BCH4 => ecc.strength = 4
1702 	 * BCH8 => ecc.strength = 8
1703 	 * ECC sector size = 512
1704 	 */
1705 	if (chip->ecc.engine_type != NAND_ECC_ENGINE_TYPE_ON_HOST) {
1706 		dev_err(nfc->dev,
1707 			"nand_ecc_engine_type is not well defined in the DT\n");
1708 		return -EINVAL;
1709 	}
1710 
1711 	ret = nand_ecc_choose_conf(chip, &stm32_fmc2_nfc_ecc_caps,
1712 				   mtd->oobsize - FMC2_BBM_LEN);
1713 	if (ret) {
1714 		dev_err(nfc->dev, "no valid ECC settings set\n");
1715 		return ret;
1716 	}
1717 
1718 	if (mtd->writesize / chip->ecc.size > FMC2_MAX_SG) {
1719 		dev_err(nfc->dev, "nand page size is not supported\n");
1720 		return -EINVAL;
1721 	}
1722 
1723 	if (chip->bbt_options & NAND_BBT_USE_FLASH)
1724 		chip->bbt_options |= NAND_BBT_NO_OOB;
1725 
1726 	stm32_fmc2_nfc_nand_callbacks_setup(chip);
1727 
1728 	mtd_set_ooblayout(mtd, &stm32_fmc2_nfc_ooblayout_ops);
1729 
1730 	if (chip->options & NAND_BUSWIDTH_16)
1731 		stm32_fmc2_nfc_set_buswidth_16(nfc, true);
1732 
1733 	return 0;
1734 }
1735 
1736 static const struct nand_controller_ops stm32_fmc2_nfc_controller_ops = {
1737 	.attach_chip = stm32_fmc2_nfc_attach_chip,
1738 	.exec_op = stm32_fmc2_nfc_exec_op,
1739 	.setup_interface = stm32_fmc2_nfc_setup_interface,
1740 };
1741 
1742 static int stm32_fmc2_nfc_parse_child(struct stm32_fmc2_nfc *nfc,
1743 				      struct device_node *dn)
1744 {
1745 	struct stm32_fmc2_nand *nand = &nfc->nand;
1746 	u32 cs;
1747 	int ret, i;
1748 
1749 	if (!of_get_property(dn, "reg", &nand->ncs))
1750 		return -EINVAL;
1751 
1752 	nand->ncs /= sizeof(u32);
1753 	if (!nand->ncs) {
1754 		dev_err(nfc->dev, "invalid reg property size\n");
1755 		return -EINVAL;
1756 	}
1757 
1758 	for (i = 0; i < nand->ncs; i++) {
1759 		ret = of_property_read_u32_index(dn, "reg", i, &cs);
1760 		if (ret) {
1761 			dev_err(nfc->dev, "could not retrieve reg property: %d\n",
1762 				ret);
1763 			return ret;
1764 		}
1765 
1766 		if (cs >= FMC2_MAX_CE) {
1767 			dev_err(nfc->dev, "invalid reg value: %d\n", cs);
1768 			return -EINVAL;
1769 		}
1770 
1771 		if (nfc->cs_assigned & BIT(cs)) {
1772 			dev_err(nfc->dev, "cs already assigned: %d\n", cs);
1773 			return -EINVAL;
1774 		}
1775 
1776 		nfc->cs_assigned |= BIT(cs);
1777 		nand->cs_used[i] = cs;
1778 	}
1779 
1780 	nand_set_flash_node(&nand->chip, dn);
1781 
1782 	return 0;
1783 }
1784 
1785 static int stm32_fmc2_nfc_parse_dt(struct stm32_fmc2_nfc *nfc)
1786 {
1787 	struct device_node *dn = nfc->dev->of_node;
1788 	struct device_node *child;
1789 	int nchips = of_get_child_count(dn);
1790 	int ret = 0;
1791 
1792 	if (!nchips) {
1793 		dev_err(nfc->dev, "NAND chip not defined\n");
1794 		return -EINVAL;
1795 	}
1796 
1797 	if (nchips > 1) {
1798 		dev_err(nfc->dev, "too many NAND chips defined\n");
1799 		return -EINVAL;
1800 	}
1801 
1802 	for_each_child_of_node(dn, child) {
1803 		ret = stm32_fmc2_nfc_parse_child(nfc, child);
1804 		if (ret < 0) {
1805 			of_node_put(child);
1806 			return ret;
1807 		}
1808 	}
1809 
1810 	return ret;
1811 }
1812 
1813 static int stm32_fmc2_nfc_set_cdev(struct stm32_fmc2_nfc *nfc)
1814 {
1815 	struct device *dev = nfc->dev;
1816 	bool ebi_found = false;
1817 
1818 	if (dev->parent && of_device_is_compatible(dev->parent->of_node,
1819 						   "st,stm32mp1-fmc2-ebi"))
1820 		ebi_found = true;
1821 
1822 	if (of_device_is_compatible(dev->of_node, "st,stm32mp1-fmc2-nfc")) {
1823 		if (ebi_found) {
1824 			nfc->cdev = dev->parent;
1825 
1826 			return 0;
1827 		}
1828 
1829 		return -EINVAL;
1830 	}
1831 
1832 	if (ebi_found)
1833 		return -EINVAL;
1834 
1835 	nfc->cdev = dev;
1836 
1837 	return 0;
1838 }
1839 
1840 static int stm32_fmc2_nfc_probe(struct platform_device *pdev)
1841 {
1842 	struct device *dev = &pdev->dev;
1843 	struct reset_control *rstc;
1844 	struct stm32_fmc2_nfc *nfc;
1845 	struct stm32_fmc2_nand *nand;
1846 	struct resource *res;
1847 	struct mtd_info *mtd;
1848 	struct nand_chip *chip;
1849 	struct resource cres;
1850 	int chip_cs, mem_region, ret, irq;
1851 	int start_region = 0;
1852 
1853 	nfc = devm_kzalloc(dev, sizeof(*nfc), GFP_KERNEL);
1854 	if (!nfc)
1855 		return -ENOMEM;
1856 
1857 	nfc->dev = dev;
1858 	nand_controller_init(&nfc->base);
1859 	nfc->base.ops = &stm32_fmc2_nfc_controller_ops;
1860 
1861 	ret = stm32_fmc2_nfc_set_cdev(nfc);
1862 	if (ret)
1863 		return ret;
1864 
1865 	ret = stm32_fmc2_nfc_parse_dt(nfc);
1866 	if (ret)
1867 		return ret;
1868 
1869 	ret = of_address_to_resource(nfc->cdev->of_node, 0, &cres);
1870 	if (ret)
1871 		return ret;
1872 
1873 	nfc->io_phys_addr = cres.start;
1874 
1875 	nfc->regmap = device_node_to_regmap(nfc->cdev->of_node);
1876 	if (IS_ERR(nfc->regmap))
1877 		return PTR_ERR(nfc->regmap);
1878 
1879 	if (nfc->dev == nfc->cdev)
1880 		start_region = 1;
1881 
1882 	for (chip_cs = 0, mem_region = start_region; chip_cs < FMC2_MAX_CE;
1883 	     chip_cs++, mem_region += 3) {
1884 		if (!(nfc->cs_assigned & BIT(chip_cs)))
1885 			continue;
1886 
1887 		res = platform_get_resource(pdev, IORESOURCE_MEM, mem_region);
1888 		nfc->data_base[chip_cs] = devm_ioremap_resource(dev, res);
1889 		if (IS_ERR(nfc->data_base[chip_cs]))
1890 			return PTR_ERR(nfc->data_base[chip_cs]);
1891 
1892 		nfc->data_phys_addr[chip_cs] = res->start;
1893 
1894 		res = platform_get_resource(pdev, IORESOURCE_MEM,
1895 					    mem_region + 1);
1896 		nfc->cmd_base[chip_cs] = devm_ioremap_resource(dev, res);
1897 		if (IS_ERR(nfc->cmd_base[chip_cs]))
1898 			return PTR_ERR(nfc->cmd_base[chip_cs]);
1899 
1900 		res = platform_get_resource(pdev, IORESOURCE_MEM,
1901 					    mem_region + 2);
1902 		nfc->addr_base[chip_cs] = devm_ioremap_resource(dev, res);
1903 		if (IS_ERR(nfc->addr_base[chip_cs]))
1904 			return PTR_ERR(nfc->addr_base[chip_cs]);
1905 	}
1906 
1907 	irq = platform_get_irq(pdev, 0);
1908 	if (irq < 0)
1909 		return irq;
1910 
1911 	ret = devm_request_irq(dev, irq, stm32_fmc2_nfc_irq, 0,
1912 			       dev_name(dev), nfc);
1913 	if (ret) {
1914 		dev_err(dev, "failed to request irq\n");
1915 		return ret;
1916 	}
1917 
1918 	init_completion(&nfc->complete);
1919 
1920 	nfc->clk = devm_clk_get(nfc->cdev, NULL);
1921 	if (IS_ERR(nfc->clk))
1922 		return PTR_ERR(nfc->clk);
1923 
1924 	ret = clk_prepare_enable(nfc->clk);
1925 	if (ret) {
1926 		dev_err(dev, "can not enable the clock\n");
1927 		return ret;
1928 	}
1929 
1930 	rstc = devm_reset_control_get(dev, NULL);
1931 	if (IS_ERR(rstc)) {
1932 		ret = PTR_ERR(rstc);
1933 		if (ret == -EPROBE_DEFER)
1934 			goto err_clk_disable;
1935 	} else {
1936 		reset_control_assert(rstc);
1937 		reset_control_deassert(rstc);
1938 	}
1939 
1940 	ret = stm32_fmc2_nfc_dma_setup(nfc);
1941 	if (ret)
1942 		goto err_release_dma;
1943 
1944 	stm32_fmc2_nfc_init(nfc);
1945 
1946 	nand = &nfc->nand;
1947 	chip = &nand->chip;
1948 	mtd = nand_to_mtd(chip);
1949 	mtd->dev.parent = dev;
1950 
1951 	chip->controller = &nfc->base;
1952 	chip->options |= NAND_BUSWIDTH_AUTO | NAND_NO_SUBPAGE_WRITE |
1953 			 NAND_USES_DMA;
1954 
1955 	/* Default ECC settings */
1956 	chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST;
1957 	chip->ecc.size = FMC2_ECC_STEP_SIZE;
1958 	chip->ecc.strength = FMC2_ECC_BCH8;
1959 
1960 	/* Scan to find existence of the device */
1961 	ret = nand_scan(chip, nand->ncs);
1962 	if (ret)
1963 		goto err_release_dma;
1964 
1965 	ret = mtd_device_register(mtd, NULL, 0);
1966 	if (ret)
1967 		goto err_nand_cleanup;
1968 
1969 	platform_set_drvdata(pdev, nfc);
1970 
1971 	return 0;
1972 
1973 err_nand_cleanup:
1974 	nand_cleanup(chip);
1975 
1976 err_release_dma:
1977 	if (nfc->dma_ecc_ch)
1978 		dma_release_channel(nfc->dma_ecc_ch);
1979 	if (nfc->dma_tx_ch)
1980 		dma_release_channel(nfc->dma_tx_ch);
1981 	if (nfc->dma_rx_ch)
1982 		dma_release_channel(nfc->dma_rx_ch);
1983 
1984 	sg_free_table(&nfc->dma_data_sg);
1985 	sg_free_table(&nfc->dma_ecc_sg);
1986 
1987 err_clk_disable:
1988 	clk_disable_unprepare(nfc->clk);
1989 
1990 	return ret;
1991 }
1992 
1993 static int stm32_fmc2_nfc_remove(struct platform_device *pdev)
1994 {
1995 	struct stm32_fmc2_nfc *nfc = platform_get_drvdata(pdev);
1996 	struct stm32_fmc2_nand *nand = &nfc->nand;
1997 	struct nand_chip *chip = &nand->chip;
1998 	int ret;
1999 
2000 	ret = mtd_device_unregister(nand_to_mtd(chip));
2001 	WARN_ON(ret);
2002 	nand_cleanup(chip);
2003 
2004 	if (nfc->dma_ecc_ch)
2005 		dma_release_channel(nfc->dma_ecc_ch);
2006 	if (nfc->dma_tx_ch)
2007 		dma_release_channel(nfc->dma_tx_ch);
2008 	if (nfc->dma_rx_ch)
2009 		dma_release_channel(nfc->dma_rx_ch);
2010 
2011 	sg_free_table(&nfc->dma_data_sg);
2012 	sg_free_table(&nfc->dma_ecc_sg);
2013 
2014 	clk_disable_unprepare(nfc->clk);
2015 
2016 	return 0;
2017 }
2018 
2019 static int __maybe_unused stm32_fmc2_nfc_suspend(struct device *dev)
2020 {
2021 	struct stm32_fmc2_nfc *nfc = dev_get_drvdata(dev);
2022 
2023 	clk_disable_unprepare(nfc->clk);
2024 
2025 	pinctrl_pm_select_sleep_state(dev);
2026 
2027 	return 0;
2028 }
2029 
2030 static int __maybe_unused stm32_fmc2_nfc_resume(struct device *dev)
2031 {
2032 	struct stm32_fmc2_nfc *nfc = dev_get_drvdata(dev);
2033 	struct stm32_fmc2_nand *nand = &nfc->nand;
2034 	int chip_cs, ret;
2035 
2036 	pinctrl_pm_select_default_state(dev);
2037 
2038 	ret = clk_prepare_enable(nfc->clk);
2039 	if (ret) {
2040 		dev_err(dev, "can not enable the clock\n");
2041 		return ret;
2042 	}
2043 
2044 	stm32_fmc2_nfc_init(nfc);
2045 
2046 	for (chip_cs = 0; chip_cs < FMC2_MAX_CE; chip_cs++) {
2047 		if (!(nfc->cs_assigned & BIT(chip_cs)))
2048 			continue;
2049 
2050 		nand_reset(&nand->chip, chip_cs);
2051 	}
2052 
2053 	return 0;
2054 }
2055 
2056 static SIMPLE_DEV_PM_OPS(stm32_fmc2_nfc_pm_ops, stm32_fmc2_nfc_suspend,
2057 			 stm32_fmc2_nfc_resume);
2058 
2059 static const struct of_device_id stm32_fmc2_nfc_match[] = {
2060 	{.compatible = "st,stm32mp15-fmc2"},
2061 	{.compatible = "st,stm32mp1-fmc2-nfc"},
2062 	{}
2063 };
2064 MODULE_DEVICE_TABLE(of, stm32_fmc2_nfc_match);
2065 
2066 static struct platform_driver stm32_fmc2_nfc_driver = {
2067 	.probe	= stm32_fmc2_nfc_probe,
2068 	.remove	= stm32_fmc2_nfc_remove,
2069 	.driver	= {
2070 		.name = "stm32_fmc2_nfc",
2071 		.of_match_table = stm32_fmc2_nfc_match,
2072 		.pm = &stm32_fmc2_nfc_pm_ops,
2073 	},
2074 };
2075 module_platform_driver(stm32_fmc2_nfc_driver);
2076 
2077 MODULE_ALIAS("platform:stm32_fmc2_nfc");
2078 MODULE_AUTHOR("Christophe Kerello <christophe.kerello@st.com>");
2079 MODULE_DESCRIPTION("STMicroelectronics STM32 FMC2 NFC driver");
2080 MODULE_LICENSE("GPL v2");
2081