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/clk.h>
8 #include <linux/dmaengine.h>
9 #include <linux/dma-mapping.h>
10 #include <linux/errno.h>
11 #include <linux/interrupt.h>
12 #include <linux/iopoll.h>
13 #include <linux/module.h>
14 #include <linux/mtd/rawnand.h>
15 #include <linux/pinctrl/consumer.h>
16 #include <linux/platform_device.h>
17 #include <linux/reset.h>
18 
19 /* Bad block marker length */
20 #define FMC2_BBM_LEN			2
21 
22 /* ECC step size */
23 #define FMC2_ECC_STEP_SIZE		512
24 
25 /* BCHDSRx registers length */
26 #define FMC2_BCHDSRS_LEN		20
27 
28 /* HECCR length */
29 #define FMC2_HECCR_LEN			4
30 
31 /* Max requests done for a 8k nand page size */
32 #define FMC2_MAX_SG			16
33 
34 /* Max chip enable */
35 #define FMC2_MAX_CE			2
36 
37 /* Max ECC buffer length */
38 #define FMC2_MAX_ECC_BUF_LEN		(FMC2_BCHDSRS_LEN * FMC2_MAX_SG)
39 
40 #define FMC2_TIMEOUT_US			1000
41 #define FMC2_TIMEOUT_MS			1000
42 
43 /* Timings */
44 #define FMC2_THIZ			1
45 #define FMC2_TIO			8000
46 #define FMC2_TSYNC			3000
47 #define FMC2_PCR_TIMING_MASK		0xf
48 #define FMC2_PMEM_PATT_TIMING_MASK	0xff
49 
50 /* FMC2 Controller Registers */
51 #define FMC2_BCR1			0x0
52 #define FMC2_PCR			0x80
53 #define FMC2_SR				0x84
54 #define FMC2_PMEM			0x88
55 #define FMC2_PATT			0x8c
56 #define FMC2_HECCR			0x94
57 #define FMC2_ISR			0x184
58 #define FMC2_ICR			0x188
59 #define FMC2_CSQCR			0x200
60 #define FMC2_CSQCFGR1			0x204
61 #define FMC2_CSQCFGR2			0x208
62 #define FMC2_CSQCFGR3			0x20c
63 #define FMC2_CSQAR1			0x210
64 #define FMC2_CSQAR2			0x214
65 #define FMC2_CSQIER			0x220
66 #define FMC2_CSQISR			0x224
67 #define FMC2_CSQICR			0x228
68 #define FMC2_CSQEMSR			0x230
69 #define FMC2_BCHIER			0x250
70 #define FMC2_BCHISR			0x254
71 #define FMC2_BCHICR			0x258
72 #define FMC2_BCHPBR1			0x260
73 #define FMC2_BCHPBR2			0x264
74 #define FMC2_BCHPBR3			0x268
75 #define FMC2_BCHPBR4			0x26c
76 #define FMC2_BCHDSR0			0x27c
77 #define FMC2_BCHDSR1			0x280
78 #define FMC2_BCHDSR2			0x284
79 #define FMC2_BCHDSR3			0x288
80 #define FMC2_BCHDSR4			0x28c
81 
82 /* Register: FMC2_BCR1 */
83 #define FMC2_BCR1_FMC2EN		BIT(31)
84 
85 /* Register: FMC2_PCR */
86 #define FMC2_PCR_PWAITEN		BIT(1)
87 #define FMC2_PCR_PBKEN			BIT(2)
88 #define FMC2_PCR_PWID_MASK		GENMASK(5, 4)
89 #define FMC2_PCR_PWID(x)		(((x) & 0x3) << 4)
90 #define FMC2_PCR_PWID_BUSWIDTH_8	0
91 #define FMC2_PCR_PWID_BUSWIDTH_16	1
92 #define FMC2_PCR_ECCEN			BIT(6)
93 #define FMC2_PCR_ECCALG			BIT(8)
94 #define FMC2_PCR_TCLR_MASK		GENMASK(12, 9)
95 #define FMC2_PCR_TCLR(x)		(((x) & 0xf) << 9)
96 #define FMC2_PCR_TCLR_DEFAULT		0xf
97 #define FMC2_PCR_TAR_MASK		GENMASK(16, 13)
98 #define FMC2_PCR_TAR(x)			(((x) & 0xf) << 13)
99 #define FMC2_PCR_TAR_DEFAULT		0xf
100 #define FMC2_PCR_ECCSS_MASK		GENMASK(19, 17)
101 #define FMC2_PCR_ECCSS(x)		(((x) & 0x7) << 17)
102 #define FMC2_PCR_ECCSS_512		1
103 #define FMC2_PCR_ECCSS_2048		3
104 #define FMC2_PCR_BCHECC			BIT(24)
105 #define FMC2_PCR_WEN			BIT(25)
106 
107 /* Register: FMC2_SR */
108 #define FMC2_SR_NWRF			BIT(6)
109 
110 /* Register: FMC2_PMEM */
111 #define FMC2_PMEM_MEMSET(x)		(((x) & 0xff) << 0)
112 #define FMC2_PMEM_MEMWAIT(x)		(((x) & 0xff) << 8)
113 #define FMC2_PMEM_MEMHOLD(x)		(((x) & 0xff) << 16)
114 #define FMC2_PMEM_MEMHIZ(x)		(((x) & 0xff) << 24)
115 #define FMC2_PMEM_DEFAULT		0x0a0a0a0a
116 
117 /* Register: FMC2_PATT */
118 #define FMC2_PATT_ATTSET(x)		(((x) & 0xff) << 0)
119 #define FMC2_PATT_ATTWAIT(x)		(((x) & 0xff) << 8)
120 #define FMC2_PATT_ATTHOLD(x)		(((x) & 0xff) << 16)
121 #define FMC2_PATT_ATTHIZ(x)		(((x) & 0xff) << 24)
122 #define FMC2_PATT_DEFAULT		0x0a0a0a0a
123 
124 /* Register: FMC2_ISR */
125 #define FMC2_ISR_IHLF			BIT(1)
126 
127 /* Register: FMC2_ICR */
128 #define FMC2_ICR_CIHLF			BIT(1)
129 
130 /* Register: FMC2_CSQCR */
131 #define FMC2_CSQCR_CSQSTART		BIT(0)
132 
133 /* Register: FMC2_CSQCFGR1 */
134 #define FMC2_CSQCFGR1_CMD2EN		BIT(1)
135 #define FMC2_CSQCFGR1_DMADEN		BIT(2)
136 #define FMC2_CSQCFGR1_ACYNBR(x)		(((x) & 0x7) << 4)
137 #define FMC2_CSQCFGR1_CMD1(x)		(((x) & 0xff) << 8)
138 #define FMC2_CSQCFGR1_CMD2(x)		(((x) & 0xff) << 16)
139 #define FMC2_CSQCFGR1_CMD1T		BIT(24)
140 #define FMC2_CSQCFGR1_CMD2T		BIT(25)
141 
142 /* Register: FMC2_CSQCFGR2 */
143 #define FMC2_CSQCFGR2_SQSDTEN		BIT(0)
144 #define FMC2_CSQCFGR2_RCMD2EN		BIT(1)
145 #define FMC2_CSQCFGR2_DMASEN		BIT(2)
146 #define FMC2_CSQCFGR2_RCMD1(x)		(((x) & 0xff) << 8)
147 #define FMC2_CSQCFGR2_RCMD2(x)		(((x) & 0xff) << 16)
148 #define FMC2_CSQCFGR2_RCMD1T		BIT(24)
149 #define FMC2_CSQCFGR2_RCMD2T		BIT(25)
150 
151 /* Register: FMC2_CSQCFGR3 */
152 #define FMC2_CSQCFGR3_SNBR(x)		(((x) & 0x1f) << 8)
153 #define FMC2_CSQCFGR3_AC1T		BIT(16)
154 #define FMC2_CSQCFGR3_AC2T		BIT(17)
155 #define FMC2_CSQCFGR3_AC3T		BIT(18)
156 #define FMC2_CSQCFGR3_AC4T		BIT(19)
157 #define FMC2_CSQCFGR3_AC5T		BIT(20)
158 #define FMC2_CSQCFGR3_SDT		BIT(21)
159 #define FMC2_CSQCFGR3_RAC1T		BIT(22)
160 #define FMC2_CSQCFGR3_RAC2T		BIT(23)
161 
162 /* Register: FMC2_CSQCAR1 */
163 #define FMC2_CSQCAR1_ADDC1(x)		(((x) & 0xff) << 0)
164 #define FMC2_CSQCAR1_ADDC2(x)		(((x) & 0xff) << 8)
165 #define FMC2_CSQCAR1_ADDC3(x)		(((x) & 0xff) << 16)
166 #define FMC2_CSQCAR1_ADDC4(x)		(((x) & 0xff) << 24)
167 
168 /* Register: FMC2_CSQCAR2 */
169 #define FMC2_CSQCAR2_ADDC5(x)		(((x) & 0xff) << 0)
170 #define FMC2_CSQCAR2_NANDCEN(x)		(((x) & 0x3) << 10)
171 #define FMC2_CSQCAR2_SAO(x)		(((x) & 0xffff) << 16)
172 
173 /* Register: FMC2_CSQIER */
174 #define FMC2_CSQIER_TCIE		BIT(0)
175 
176 /* Register: FMC2_CSQICR */
177 #define FMC2_CSQICR_CLEAR_IRQ		GENMASK(4, 0)
178 
179 /* Register: FMC2_CSQEMSR */
180 #define FMC2_CSQEMSR_SEM		GENMASK(15, 0)
181 
182 /* Register: FMC2_BCHIER */
183 #define FMC2_BCHIER_DERIE		BIT(1)
184 #define FMC2_BCHIER_EPBRIE		BIT(4)
185 
186 /* Register: FMC2_BCHICR */
187 #define FMC2_BCHICR_CLEAR_IRQ		GENMASK(4, 0)
188 
189 /* Register: FMC2_BCHDSR0 */
190 #define FMC2_BCHDSR0_DUE		BIT(0)
191 #define FMC2_BCHDSR0_DEF		BIT(1)
192 #define FMC2_BCHDSR0_DEN_MASK		GENMASK(7, 4)
193 #define FMC2_BCHDSR0_DEN_SHIFT		4
194 
195 /* Register: FMC2_BCHDSR1 */
196 #define FMC2_BCHDSR1_EBP1_MASK		GENMASK(12, 0)
197 #define FMC2_BCHDSR1_EBP2_MASK		GENMASK(28, 16)
198 #define FMC2_BCHDSR1_EBP2_SHIFT		16
199 
200 /* Register: FMC2_BCHDSR2 */
201 #define FMC2_BCHDSR2_EBP3_MASK		GENMASK(12, 0)
202 #define FMC2_BCHDSR2_EBP4_MASK		GENMASK(28, 16)
203 #define FMC2_BCHDSR2_EBP4_SHIFT		16
204 
205 /* Register: FMC2_BCHDSR3 */
206 #define FMC2_BCHDSR3_EBP5_MASK		GENMASK(12, 0)
207 #define FMC2_BCHDSR3_EBP6_MASK		GENMASK(28, 16)
208 #define FMC2_BCHDSR3_EBP6_SHIFT		16
209 
210 /* Register: FMC2_BCHDSR4 */
211 #define FMC2_BCHDSR4_EBP7_MASK		GENMASK(12, 0)
212 #define FMC2_BCHDSR4_EBP8_MASK		GENMASK(28, 16)
213 #define FMC2_BCHDSR4_EBP8_SHIFT		16
214 
215 enum stm32_fmc2_ecc {
216 	FMC2_ECC_HAM = 1,
217 	FMC2_ECC_BCH4 = 4,
218 	FMC2_ECC_BCH8 = 8
219 };
220 
221 enum stm32_fmc2_irq_state {
222 	FMC2_IRQ_UNKNOWN = 0,
223 	FMC2_IRQ_BCH,
224 	FMC2_IRQ_SEQ
225 };
226 
227 struct stm32_fmc2_timings {
228 	u8 tclr;
229 	u8 tar;
230 	u8 thiz;
231 	u8 twait;
232 	u8 thold_mem;
233 	u8 tset_mem;
234 	u8 thold_att;
235 	u8 tset_att;
236 };
237 
238 struct stm32_fmc2_nand {
239 	struct nand_chip chip;
240 	struct stm32_fmc2_timings timings;
241 	int ncs;
242 	int cs_used[FMC2_MAX_CE];
243 };
244 
245 static inline struct stm32_fmc2_nand *to_fmc2_nand(struct nand_chip *chip)
246 {
247 	return container_of(chip, struct stm32_fmc2_nand, chip);
248 }
249 
250 struct stm32_fmc2_nfc {
251 	struct nand_controller base;
252 	struct stm32_fmc2_nand nand;
253 	struct device *dev;
254 	void __iomem *io_base;
255 	void __iomem *data_base[FMC2_MAX_CE];
256 	void __iomem *cmd_base[FMC2_MAX_CE];
257 	void __iomem *addr_base[FMC2_MAX_CE];
258 	phys_addr_t io_phys_addr;
259 	phys_addr_t data_phys_addr[FMC2_MAX_CE];
260 	struct clk *clk;
261 	u8 irq_state;
262 
263 	struct dma_chan *dma_tx_ch;
264 	struct dma_chan *dma_rx_ch;
265 	struct dma_chan *dma_ecc_ch;
266 	struct sg_table dma_data_sg;
267 	struct sg_table dma_ecc_sg;
268 	u8 *ecc_buf;
269 	int dma_ecc_len;
270 
271 	struct completion complete;
272 	struct completion dma_data_complete;
273 	struct completion dma_ecc_complete;
274 
275 	u8 cs_assigned;
276 	int cs_sel;
277 };
278 
279 static inline struct stm32_fmc2_nfc *to_stm32_nfc(struct nand_controller *base)
280 {
281 	return container_of(base, struct stm32_fmc2_nfc, base);
282 }
283 
284 /* Timings configuration */
285 static void stm32_fmc2_timings_init(struct nand_chip *chip)
286 {
287 	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
288 	struct stm32_fmc2_nand *nand = to_fmc2_nand(chip);
289 	struct stm32_fmc2_timings *timings = &nand->timings;
290 	u32 pcr = readl_relaxed(fmc2->io_base + FMC2_PCR);
291 	u32 pmem, patt;
292 
293 	/* Set tclr/tar timings */
294 	pcr &= ~FMC2_PCR_TCLR_MASK;
295 	pcr |= FMC2_PCR_TCLR(timings->tclr);
296 	pcr &= ~FMC2_PCR_TAR_MASK;
297 	pcr |= FMC2_PCR_TAR(timings->tar);
298 
299 	/* Set tset/twait/thold/thiz timings in common bank */
300 	pmem = FMC2_PMEM_MEMSET(timings->tset_mem);
301 	pmem |= FMC2_PMEM_MEMWAIT(timings->twait);
302 	pmem |= FMC2_PMEM_MEMHOLD(timings->thold_mem);
303 	pmem |= FMC2_PMEM_MEMHIZ(timings->thiz);
304 
305 	/* Set tset/twait/thold/thiz timings in attribut bank */
306 	patt = FMC2_PATT_ATTSET(timings->tset_att);
307 	patt |= FMC2_PATT_ATTWAIT(timings->twait);
308 	patt |= FMC2_PATT_ATTHOLD(timings->thold_att);
309 	patt |= FMC2_PATT_ATTHIZ(timings->thiz);
310 
311 	writel_relaxed(pcr, fmc2->io_base + FMC2_PCR);
312 	writel_relaxed(pmem, fmc2->io_base + FMC2_PMEM);
313 	writel_relaxed(patt, fmc2->io_base + FMC2_PATT);
314 }
315 
316 /* Controller configuration */
317 static void stm32_fmc2_setup(struct nand_chip *chip)
318 {
319 	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
320 	u32 pcr = readl_relaxed(fmc2->io_base + FMC2_PCR);
321 
322 	/* Configure ECC algorithm (default configuration is Hamming) */
323 	pcr &= ~FMC2_PCR_ECCALG;
324 	pcr &= ~FMC2_PCR_BCHECC;
325 	if (chip->ecc.strength == FMC2_ECC_BCH8) {
326 		pcr |= FMC2_PCR_ECCALG;
327 		pcr |= FMC2_PCR_BCHECC;
328 	} else if (chip->ecc.strength == FMC2_ECC_BCH4) {
329 		pcr |= FMC2_PCR_ECCALG;
330 	}
331 
332 	/* Set buswidth */
333 	pcr &= ~FMC2_PCR_PWID_MASK;
334 	if (chip->options & NAND_BUSWIDTH_16)
335 		pcr |= FMC2_PCR_PWID(FMC2_PCR_PWID_BUSWIDTH_16);
336 
337 	/* Set ECC sector size */
338 	pcr &= ~FMC2_PCR_ECCSS_MASK;
339 	pcr |= FMC2_PCR_ECCSS(FMC2_PCR_ECCSS_512);
340 
341 	writel_relaxed(pcr, fmc2->io_base + FMC2_PCR);
342 }
343 
344 /* Select target */
345 static int stm32_fmc2_select_chip(struct nand_chip *chip, int chipnr)
346 {
347 	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
348 	struct stm32_fmc2_nand *nand = to_fmc2_nand(chip);
349 	struct dma_slave_config dma_cfg;
350 	int ret;
351 
352 	if (nand->cs_used[chipnr] == fmc2->cs_sel)
353 		return 0;
354 
355 	fmc2->cs_sel = nand->cs_used[chipnr];
356 
357 	/* FMC2 setup routine */
358 	stm32_fmc2_setup(chip);
359 
360 	/* Apply timings */
361 	stm32_fmc2_timings_init(chip);
362 
363 	if (fmc2->dma_tx_ch && fmc2->dma_rx_ch) {
364 		memset(&dma_cfg, 0, sizeof(dma_cfg));
365 		dma_cfg.src_addr = fmc2->data_phys_addr[fmc2->cs_sel];
366 		dma_cfg.dst_addr = fmc2->data_phys_addr[fmc2->cs_sel];
367 		dma_cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
368 		dma_cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
369 		dma_cfg.src_maxburst = 32;
370 		dma_cfg.dst_maxburst = 32;
371 
372 		ret = dmaengine_slave_config(fmc2->dma_tx_ch, &dma_cfg);
373 		if (ret) {
374 			dev_err(fmc2->dev, "tx DMA engine slave config failed\n");
375 			return ret;
376 		}
377 
378 		ret = dmaengine_slave_config(fmc2->dma_rx_ch, &dma_cfg);
379 		if (ret) {
380 			dev_err(fmc2->dev, "rx DMA engine slave config failed\n");
381 			return ret;
382 		}
383 	}
384 
385 	if (fmc2->dma_ecc_ch) {
386 		/*
387 		 * Hamming: we read HECCR register
388 		 * BCH4/BCH8: we read BCHDSRSx registers
389 		 */
390 		memset(&dma_cfg, 0, sizeof(dma_cfg));
391 		dma_cfg.src_addr = fmc2->io_phys_addr;
392 		dma_cfg.src_addr += chip->ecc.strength == FMC2_ECC_HAM ?
393 				    FMC2_HECCR : FMC2_BCHDSR0;
394 		dma_cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
395 
396 		ret = dmaengine_slave_config(fmc2->dma_ecc_ch, &dma_cfg);
397 		if (ret) {
398 			dev_err(fmc2->dev, "ECC DMA engine slave config failed\n");
399 			return ret;
400 		}
401 
402 		/* Calculate ECC length needed for one sector */
403 		fmc2->dma_ecc_len = chip->ecc.strength == FMC2_ECC_HAM ?
404 				    FMC2_HECCR_LEN : FMC2_BCHDSRS_LEN;
405 	}
406 
407 	return 0;
408 }
409 
410 /* Set bus width to 16-bit or 8-bit */
411 static void stm32_fmc2_set_buswidth_16(struct stm32_fmc2_nfc *fmc2, bool set)
412 {
413 	u32 pcr = readl_relaxed(fmc2->io_base + FMC2_PCR);
414 
415 	pcr &= ~FMC2_PCR_PWID_MASK;
416 	if (set)
417 		pcr |= FMC2_PCR_PWID(FMC2_PCR_PWID_BUSWIDTH_16);
418 	writel_relaxed(pcr, fmc2->io_base + FMC2_PCR);
419 }
420 
421 /* Enable/disable ECC */
422 static void stm32_fmc2_set_ecc(struct stm32_fmc2_nfc *fmc2, bool enable)
423 {
424 	u32 pcr = readl(fmc2->io_base + FMC2_PCR);
425 
426 	pcr &= ~FMC2_PCR_ECCEN;
427 	if (enable)
428 		pcr |= FMC2_PCR_ECCEN;
429 	writel(pcr, fmc2->io_base + FMC2_PCR);
430 }
431 
432 /* Enable irq sources in case of the sequencer is used */
433 static inline void stm32_fmc2_enable_seq_irq(struct stm32_fmc2_nfc *fmc2)
434 {
435 	u32 csqier = readl_relaxed(fmc2->io_base + FMC2_CSQIER);
436 
437 	csqier |= FMC2_CSQIER_TCIE;
438 
439 	fmc2->irq_state = FMC2_IRQ_SEQ;
440 
441 	writel_relaxed(csqier, fmc2->io_base + FMC2_CSQIER);
442 }
443 
444 /* Disable irq sources in case of the sequencer is used */
445 static inline void stm32_fmc2_disable_seq_irq(struct stm32_fmc2_nfc *fmc2)
446 {
447 	u32 csqier = readl_relaxed(fmc2->io_base + FMC2_CSQIER);
448 
449 	csqier &= ~FMC2_CSQIER_TCIE;
450 
451 	writel_relaxed(csqier, fmc2->io_base + FMC2_CSQIER);
452 
453 	fmc2->irq_state = FMC2_IRQ_UNKNOWN;
454 }
455 
456 /* Clear irq sources in case of the sequencer is used */
457 static inline void stm32_fmc2_clear_seq_irq(struct stm32_fmc2_nfc *fmc2)
458 {
459 	writel_relaxed(FMC2_CSQICR_CLEAR_IRQ, fmc2->io_base + FMC2_CSQICR);
460 }
461 
462 /* Enable irq sources in case of bch is used */
463 static inline void stm32_fmc2_enable_bch_irq(struct stm32_fmc2_nfc *fmc2,
464 					     int mode)
465 {
466 	u32 bchier = readl_relaxed(fmc2->io_base + FMC2_BCHIER);
467 
468 	if (mode == NAND_ECC_WRITE)
469 		bchier |= FMC2_BCHIER_EPBRIE;
470 	else
471 		bchier |= FMC2_BCHIER_DERIE;
472 
473 	fmc2->irq_state = FMC2_IRQ_BCH;
474 
475 	writel_relaxed(bchier, fmc2->io_base + FMC2_BCHIER);
476 }
477 
478 /* Disable irq sources in case of bch is used */
479 static inline void stm32_fmc2_disable_bch_irq(struct stm32_fmc2_nfc *fmc2)
480 {
481 	u32 bchier = readl_relaxed(fmc2->io_base + FMC2_BCHIER);
482 
483 	bchier &= ~FMC2_BCHIER_DERIE;
484 	bchier &= ~FMC2_BCHIER_EPBRIE;
485 
486 	writel_relaxed(bchier, fmc2->io_base + FMC2_BCHIER);
487 
488 	fmc2->irq_state = FMC2_IRQ_UNKNOWN;
489 }
490 
491 /* Clear irq sources in case of bch is used */
492 static inline void stm32_fmc2_clear_bch_irq(struct stm32_fmc2_nfc *fmc2)
493 {
494 	writel_relaxed(FMC2_BCHICR_CLEAR_IRQ, fmc2->io_base + FMC2_BCHICR);
495 }
496 
497 /*
498  * Enable ECC logic and reset syndrome/parity bits previously calculated
499  * Syndrome/parity bits is cleared by setting the ECCEN bit to 0
500  */
501 static void stm32_fmc2_hwctl(struct nand_chip *chip, int mode)
502 {
503 	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
504 
505 	stm32_fmc2_set_ecc(fmc2, false);
506 
507 	if (chip->ecc.strength != FMC2_ECC_HAM) {
508 		u32 pcr = readl_relaxed(fmc2->io_base + FMC2_PCR);
509 
510 		if (mode == NAND_ECC_WRITE)
511 			pcr |= FMC2_PCR_WEN;
512 		else
513 			pcr &= ~FMC2_PCR_WEN;
514 		writel_relaxed(pcr, fmc2->io_base + FMC2_PCR);
515 
516 		reinit_completion(&fmc2->complete);
517 		stm32_fmc2_clear_bch_irq(fmc2);
518 		stm32_fmc2_enable_bch_irq(fmc2, mode);
519 	}
520 
521 	stm32_fmc2_set_ecc(fmc2, true);
522 }
523 
524 /*
525  * ECC Hamming calculation
526  * ECC is 3 bytes for 512 bytes of data (supports error correction up to
527  * max of 1-bit)
528  */
529 static inline void stm32_fmc2_ham_set_ecc(const u32 ecc_sta, u8 *ecc)
530 {
531 	ecc[0] = ecc_sta;
532 	ecc[1] = ecc_sta >> 8;
533 	ecc[2] = ecc_sta >> 16;
534 }
535 
536 static int stm32_fmc2_ham_calculate(struct nand_chip *chip, const u8 *data,
537 				    u8 *ecc)
538 {
539 	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
540 	u32 sr, heccr;
541 	int ret;
542 
543 	ret = readl_relaxed_poll_timeout(fmc2->io_base + FMC2_SR,
544 					 sr, sr & FMC2_SR_NWRF, 10,
545 					 FMC2_TIMEOUT_MS);
546 	if (ret) {
547 		dev_err(fmc2->dev, "ham timeout\n");
548 		return ret;
549 	}
550 
551 	heccr = readl_relaxed(fmc2->io_base + FMC2_HECCR);
552 
553 	stm32_fmc2_ham_set_ecc(heccr, ecc);
554 
555 	/* Disable ECC */
556 	stm32_fmc2_set_ecc(fmc2, false);
557 
558 	return 0;
559 }
560 
561 static int stm32_fmc2_ham_correct(struct nand_chip *chip, u8 *dat,
562 				  u8 *read_ecc, u8 *calc_ecc)
563 {
564 	u8 bit_position = 0, b0, b1, b2;
565 	u32 byte_addr = 0, b;
566 	u32 i, shifting = 1;
567 
568 	/* Indicate which bit and byte is faulty (if any) */
569 	b0 = read_ecc[0] ^ calc_ecc[0];
570 	b1 = read_ecc[1] ^ calc_ecc[1];
571 	b2 = read_ecc[2] ^ calc_ecc[2];
572 	b = b0 | (b1 << 8) | (b2 << 16);
573 
574 	/* No errors */
575 	if (likely(!b))
576 		return 0;
577 
578 	/* Calculate bit position */
579 	for (i = 0; i < 3; i++) {
580 		switch (b % 4) {
581 		case 2:
582 			bit_position += shifting;
583 		case 1:
584 			break;
585 		default:
586 			return -EBADMSG;
587 		}
588 		shifting <<= 1;
589 		b >>= 2;
590 	}
591 
592 	/* Calculate byte position */
593 	shifting = 1;
594 	for (i = 0; i < 9; i++) {
595 		switch (b % 4) {
596 		case 2:
597 			byte_addr += shifting;
598 		case 1:
599 			break;
600 		default:
601 			return -EBADMSG;
602 		}
603 		shifting <<= 1;
604 		b >>= 2;
605 	}
606 
607 	/* Flip the bit */
608 	dat[byte_addr] ^= (1 << bit_position);
609 
610 	return 1;
611 }
612 
613 /*
614  * ECC BCH calculation and correction
615  * ECC is 7/13 bytes for 512 bytes of data (supports error correction up to
616  * max of 4-bit/8-bit)
617  */
618 static int stm32_fmc2_bch_calculate(struct nand_chip *chip, const u8 *data,
619 				    u8 *ecc)
620 {
621 	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
622 	u32 bchpbr;
623 
624 	/* Wait until the BCH code is ready */
625 	if (!wait_for_completion_timeout(&fmc2->complete,
626 					 msecs_to_jiffies(FMC2_TIMEOUT_MS))) {
627 		dev_err(fmc2->dev, "bch timeout\n");
628 		stm32_fmc2_disable_bch_irq(fmc2);
629 		return -ETIMEDOUT;
630 	}
631 
632 	/* Read parity bits */
633 	bchpbr = readl_relaxed(fmc2->io_base + FMC2_BCHPBR1);
634 	ecc[0] = bchpbr;
635 	ecc[1] = bchpbr >> 8;
636 	ecc[2] = bchpbr >> 16;
637 	ecc[3] = bchpbr >> 24;
638 
639 	bchpbr = readl_relaxed(fmc2->io_base + FMC2_BCHPBR2);
640 	ecc[4] = bchpbr;
641 	ecc[5] = bchpbr >> 8;
642 	ecc[6] = bchpbr >> 16;
643 
644 	if (chip->ecc.strength == FMC2_ECC_BCH8) {
645 		ecc[7] = bchpbr >> 24;
646 
647 		bchpbr = readl_relaxed(fmc2->io_base + FMC2_BCHPBR3);
648 		ecc[8] = bchpbr;
649 		ecc[9] = bchpbr >> 8;
650 		ecc[10] = bchpbr >> 16;
651 		ecc[11] = bchpbr >> 24;
652 
653 		bchpbr = readl_relaxed(fmc2->io_base + FMC2_BCHPBR4);
654 		ecc[12] = bchpbr;
655 	}
656 
657 	/* Disable ECC */
658 	stm32_fmc2_set_ecc(fmc2, false);
659 
660 	return 0;
661 }
662 
663 /* BCH algorithm correction */
664 static int stm32_fmc2_bch_decode(int eccsize, u8 *dat, u32 *ecc_sta)
665 {
666 	u32 bchdsr0 = ecc_sta[0];
667 	u32 bchdsr1 = ecc_sta[1];
668 	u32 bchdsr2 = ecc_sta[2];
669 	u32 bchdsr3 = ecc_sta[3];
670 	u32 bchdsr4 = ecc_sta[4];
671 	u16 pos[8];
672 	int i, den;
673 	unsigned int nb_errs = 0;
674 
675 	/* No errors found */
676 	if (likely(!(bchdsr0 & FMC2_BCHDSR0_DEF)))
677 		return 0;
678 
679 	/* Too many errors detected */
680 	if (unlikely(bchdsr0 & FMC2_BCHDSR0_DUE))
681 		return -EBADMSG;
682 
683 	pos[0] = bchdsr1 & FMC2_BCHDSR1_EBP1_MASK;
684 	pos[1] = (bchdsr1 & FMC2_BCHDSR1_EBP2_MASK) >> FMC2_BCHDSR1_EBP2_SHIFT;
685 	pos[2] = bchdsr2 & FMC2_BCHDSR2_EBP3_MASK;
686 	pos[3] = (bchdsr2 & FMC2_BCHDSR2_EBP4_MASK) >> FMC2_BCHDSR2_EBP4_SHIFT;
687 	pos[4] = bchdsr3 & FMC2_BCHDSR3_EBP5_MASK;
688 	pos[5] = (bchdsr3 & FMC2_BCHDSR3_EBP6_MASK) >> FMC2_BCHDSR3_EBP6_SHIFT;
689 	pos[6] = bchdsr4 & FMC2_BCHDSR4_EBP7_MASK;
690 	pos[7] = (bchdsr4 & FMC2_BCHDSR4_EBP8_MASK) >> FMC2_BCHDSR4_EBP8_SHIFT;
691 
692 	den = (bchdsr0 & FMC2_BCHDSR0_DEN_MASK) >> FMC2_BCHDSR0_DEN_SHIFT;
693 	for (i = 0; i < den; i++) {
694 		if (pos[i] < eccsize * 8) {
695 			change_bit(pos[i], (unsigned long *)dat);
696 			nb_errs++;
697 		}
698 	}
699 
700 	return nb_errs;
701 }
702 
703 static int stm32_fmc2_bch_correct(struct nand_chip *chip, u8 *dat,
704 				  u8 *read_ecc, u8 *calc_ecc)
705 {
706 	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
707 	u32 ecc_sta[5];
708 
709 	/* Wait until the decoding error is ready */
710 	if (!wait_for_completion_timeout(&fmc2->complete,
711 					 msecs_to_jiffies(FMC2_TIMEOUT_MS))) {
712 		dev_err(fmc2->dev, "bch timeout\n");
713 		stm32_fmc2_disable_bch_irq(fmc2);
714 		return -ETIMEDOUT;
715 	}
716 
717 	ecc_sta[0] = readl_relaxed(fmc2->io_base + FMC2_BCHDSR0);
718 	ecc_sta[1] = readl_relaxed(fmc2->io_base + FMC2_BCHDSR1);
719 	ecc_sta[2] = readl_relaxed(fmc2->io_base + FMC2_BCHDSR2);
720 	ecc_sta[3] = readl_relaxed(fmc2->io_base + FMC2_BCHDSR3);
721 	ecc_sta[4] = readl_relaxed(fmc2->io_base + FMC2_BCHDSR4);
722 
723 	/* Disable ECC */
724 	stm32_fmc2_set_ecc(fmc2, false);
725 
726 	return stm32_fmc2_bch_decode(chip->ecc.size, dat, ecc_sta);
727 }
728 
729 static int stm32_fmc2_read_page(struct nand_chip *chip, u8 *buf,
730 				int oob_required, int page)
731 {
732 	struct mtd_info *mtd = nand_to_mtd(chip);
733 	int ret, i, s, stat, eccsize = chip->ecc.size;
734 	int eccbytes = chip->ecc.bytes;
735 	int eccsteps = chip->ecc.steps;
736 	int eccstrength = chip->ecc.strength;
737 	u8 *p = buf;
738 	u8 *ecc_calc = chip->ecc.calc_buf;
739 	u8 *ecc_code = chip->ecc.code_buf;
740 	unsigned int max_bitflips = 0;
741 
742 	ret = nand_read_page_op(chip, page, 0, NULL, 0);
743 	if (ret)
744 		return ret;
745 
746 	for (i = mtd->writesize + FMC2_BBM_LEN, s = 0; s < eccsteps;
747 	     s++, i += eccbytes, p += eccsize) {
748 		chip->ecc.hwctl(chip, NAND_ECC_READ);
749 
750 		/* Read the nand page sector (512 bytes) */
751 		ret = nand_change_read_column_op(chip, s * eccsize, p,
752 						 eccsize, false);
753 		if (ret)
754 			return ret;
755 
756 		/* Read the corresponding ECC bytes */
757 		ret = nand_change_read_column_op(chip, i, ecc_code,
758 						 eccbytes, false);
759 		if (ret)
760 			return ret;
761 
762 		/* Correct the data */
763 		stat = chip->ecc.correct(chip, p, ecc_code, ecc_calc);
764 		if (stat == -EBADMSG)
765 			/* Check for empty pages with bitflips */
766 			stat = nand_check_erased_ecc_chunk(p, eccsize,
767 							   ecc_code, eccbytes,
768 							   NULL, 0,
769 							   eccstrength);
770 
771 		if (stat < 0) {
772 			mtd->ecc_stats.failed++;
773 		} else {
774 			mtd->ecc_stats.corrected += stat;
775 			max_bitflips = max_t(unsigned int, max_bitflips, stat);
776 		}
777 	}
778 
779 	/* Read oob */
780 	if (oob_required) {
781 		ret = nand_change_read_column_op(chip, mtd->writesize,
782 						 chip->oob_poi, mtd->oobsize,
783 						 false);
784 		if (ret)
785 			return ret;
786 	}
787 
788 	return max_bitflips;
789 }
790 
791 /* Sequencer read/write configuration */
792 static void stm32_fmc2_rw_page_init(struct nand_chip *chip, int page,
793 				    int raw, bool write_data)
794 {
795 	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
796 	struct mtd_info *mtd = nand_to_mtd(chip);
797 	u32 csqcfgr1, csqcfgr2, csqcfgr3;
798 	u32 csqar1, csqar2;
799 	u32 ecc_offset = mtd->writesize + FMC2_BBM_LEN;
800 	u32 pcr = readl_relaxed(fmc2->io_base + FMC2_PCR);
801 
802 	if (write_data)
803 		pcr |= FMC2_PCR_WEN;
804 	else
805 		pcr &= ~FMC2_PCR_WEN;
806 	writel_relaxed(pcr, fmc2->io_base + FMC2_PCR);
807 
808 	/*
809 	 * - Set Program Page/Page Read command
810 	 * - Enable DMA request data
811 	 * - Set timings
812 	 */
813 	csqcfgr1 = FMC2_CSQCFGR1_DMADEN | FMC2_CSQCFGR1_CMD1T;
814 	if (write_data)
815 		csqcfgr1 |= FMC2_CSQCFGR1_CMD1(NAND_CMD_SEQIN);
816 	else
817 		csqcfgr1 |= FMC2_CSQCFGR1_CMD1(NAND_CMD_READ0) |
818 			    FMC2_CSQCFGR1_CMD2EN |
819 			    FMC2_CSQCFGR1_CMD2(NAND_CMD_READSTART) |
820 			    FMC2_CSQCFGR1_CMD2T;
821 
822 	/*
823 	 * - Set Random Data Input/Random Data Read command
824 	 * - Enable the sequencer to access the Spare data area
825 	 * - Enable  DMA request status decoding for read
826 	 * - Set timings
827 	 */
828 	if (write_data)
829 		csqcfgr2 = FMC2_CSQCFGR2_RCMD1(NAND_CMD_RNDIN);
830 	else
831 		csqcfgr2 = FMC2_CSQCFGR2_RCMD1(NAND_CMD_RNDOUT) |
832 			   FMC2_CSQCFGR2_RCMD2EN |
833 			   FMC2_CSQCFGR2_RCMD2(NAND_CMD_RNDOUTSTART) |
834 			   FMC2_CSQCFGR2_RCMD1T |
835 			   FMC2_CSQCFGR2_RCMD2T;
836 	if (!raw) {
837 		csqcfgr2 |= write_data ? 0 : FMC2_CSQCFGR2_DMASEN;
838 		csqcfgr2 |= FMC2_CSQCFGR2_SQSDTEN;
839 	}
840 
841 	/*
842 	 * - Set the number of sectors to be written
843 	 * - Set timings
844 	 */
845 	csqcfgr3 = FMC2_CSQCFGR3_SNBR(chip->ecc.steps - 1);
846 	if (write_data) {
847 		csqcfgr3 |= FMC2_CSQCFGR3_RAC2T;
848 		if (chip->options & NAND_ROW_ADDR_3)
849 			csqcfgr3 |= FMC2_CSQCFGR3_AC5T;
850 		else
851 			csqcfgr3 |= FMC2_CSQCFGR3_AC4T;
852 	}
853 
854 	/*
855 	 * Set the fourth first address cycles
856 	 * Byte 1 and byte 2 => column, we start at 0x0
857 	 * Byte 3 and byte 4 => page
858 	 */
859 	csqar1 = FMC2_CSQCAR1_ADDC3(page);
860 	csqar1 |= FMC2_CSQCAR1_ADDC4(page >> 8);
861 
862 	/*
863 	 * - Set chip enable number
864 	 * - Set ECC byte offset in the spare area
865 	 * - Calculate the number of address cycles to be issued
866 	 * - Set byte 5 of address cycle if needed
867 	 */
868 	csqar2 = FMC2_CSQCAR2_NANDCEN(fmc2->cs_sel);
869 	if (chip->options & NAND_BUSWIDTH_16)
870 		csqar2 |= FMC2_CSQCAR2_SAO(ecc_offset >> 1);
871 	else
872 		csqar2 |= FMC2_CSQCAR2_SAO(ecc_offset);
873 	if (chip->options & NAND_ROW_ADDR_3) {
874 		csqcfgr1 |= FMC2_CSQCFGR1_ACYNBR(5);
875 		csqar2 |= FMC2_CSQCAR2_ADDC5(page >> 16);
876 	} else {
877 		csqcfgr1 |= FMC2_CSQCFGR1_ACYNBR(4);
878 	}
879 
880 	writel_relaxed(csqcfgr1, fmc2->io_base + FMC2_CSQCFGR1);
881 	writel_relaxed(csqcfgr2, fmc2->io_base + FMC2_CSQCFGR2);
882 	writel_relaxed(csqcfgr3, fmc2->io_base + FMC2_CSQCFGR3);
883 	writel_relaxed(csqar1, fmc2->io_base + FMC2_CSQAR1);
884 	writel_relaxed(csqar2, fmc2->io_base + FMC2_CSQAR2);
885 }
886 
887 static void stm32_fmc2_dma_callback(void *arg)
888 {
889 	complete((struct completion *)arg);
890 }
891 
892 /* Read/write data from/to a page */
893 static int stm32_fmc2_xfer(struct nand_chip *chip, const u8 *buf,
894 			   int raw, bool write_data)
895 {
896 	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
897 	struct dma_async_tx_descriptor *desc_data, *desc_ecc;
898 	struct scatterlist *sg;
899 	struct dma_chan *dma_ch = fmc2->dma_rx_ch;
900 	enum dma_data_direction dma_data_dir = DMA_FROM_DEVICE;
901 	enum dma_transfer_direction dma_transfer_dir = DMA_DEV_TO_MEM;
902 	u32 csqcr = readl_relaxed(fmc2->io_base + FMC2_CSQCR);
903 	int eccsteps = chip->ecc.steps;
904 	int eccsize = chip->ecc.size;
905 	const u8 *p = buf;
906 	int s, ret;
907 
908 	/* Configure DMA data */
909 	if (write_data) {
910 		dma_data_dir = DMA_TO_DEVICE;
911 		dma_transfer_dir = DMA_MEM_TO_DEV;
912 		dma_ch = fmc2->dma_tx_ch;
913 	}
914 
915 	for_each_sg(fmc2->dma_data_sg.sgl, sg, eccsteps, s) {
916 		sg_set_buf(sg, p, eccsize);
917 		p += eccsize;
918 	}
919 
920 	ret = dma_map_sg(fmc2->dev, fmc2->dma_data_sg.sgl,
921 			 eccsteps, dma_data_dir);
922 	if (ret < 0)
923 		return ret;
924 
925 	desc_data = dmaengine_prep_slave_sg(dma_ch, fmc2->dma_data_sg.sgl,
926 					    eccsteps, dma_transfer_dir,
927 					    DMA_PREP_INTERRUPT);
928 	if (!desc_data) {
929 		ret = -ENOMEM;
930 		goto err_unmap_data;
931 	}
932 
933 	reinit_completion(&fmc2->dma_data_complete);
934 	reinit_completion(&fmc2->complete);
935 	desc_data->callback = stm32_fmc2_dma_callback;
936 	desc_data->callback_param = &fmc2->dma_data_complete;
937 	ret = dma_submit_error(dmaengine_submit(desc_data));
938 	if (ret)
939 		goto err_unmap_data;
940 
941 	dma_async_issue_pending(dma_ch);
942 
943 	if (!write_data && !raw) {
944 		/* Configure DMA ECC status */
945 		p = fmc2->ecc_buf;
946 		for_each_sg(fmc2->dma_ecc_sg.sgl, sg, eccsteps, s) {
947 			sg_set_buf(sg, p, fmc2->dma_ecc_len);
948 			p += fmc2->dma_ecc_len;
949 		}
950 
951 		ret = dma_map_sg(fmc2->dev, fmc2->dma_ecc_sg.sgl,
952 				 eccsteps, dma_data_dir);
953 		if (ret < 0)
954 			goto err_unmap_data;
955 
956 		desc_ecc = dmaengine_prep_slave_sg(fmc2->dma_ecc_ch,
957 						   fmc2->dma_ecc_sg.sgl,
958 						   eccsteps, dma_transfer_dir,
959 						   DMA_PREP_INTERRUPT);
960 		if (!desc_ecc) {
961 			ret = -ENOMEM;
962 			goto err_unmap_ecc;
963 		}
964 
965 		reinit_completion(&fmc2->dma_ecc_complete);
966 		desc_ecc->callback = stm32_fmc2_dma_callback;
967 		desc_ecc->callback_param = &fmc2->dma_ecc_complete;
968 		ret = dma_submit_error(dmaengine_submit(desc_ecc));
969 		if (ret)
970 			goto err_unmap_ecc;
971 
972 		dma_async_issue_pending(fmc2->dma_ecc_ch);
973 	}
974 
975 	stm32_fmc2_clear_seq_irq(fmc2);
976 	stm32_fmc2_enable_seq_irq(fmc2);
977 
978 	/* Start the transfer */
979 	csqcr |= FMC2_CSQCR_CSQSTART;
980 	writel_relaxed(csqcr, fmc2->io_base + FMC2_CSQCR);
981 
982 	/* Wait end of sequencer transfer */
983 	if (!wait_for_completion_timeout(&fmc2->complete,
984 					 msecs_to_jiffies(FMC2_TIMEOUT_MS))) {
985 		dev_err(fmc2->dev, "seq timeout\n");
986 		stm32_fmc2_disable_seq_irq(fmc2);
987 		dmaengine_terminate_all(dma_ch);
988 		if (!write_data && !raw)
989 			dmaengine_terminate_all(fmc2->dma_ecc_ch);
990 		ret = -ETIMEDOUT;
991 		goto err_unmap_ecc;
992 	}
993 
994 	/* Wait DMA data transfer completion */
995 	if (!wait_for_completion_timeout(&fmc2->dma_data_complete,
996 					 msecs_to_jiffies(FMC2_TIMEOUT_MS))) {
997 		dev_err(fmc2->dev, "data DMA timeout\n");
998 		dmaengine_terminate_all(dma_ch);
999 		ret = -ETIMEDOUT;
1000 	}
1001 
1002 	/* Wait DMA ECC transfer completion */
1003 	if (!write_data && !raw) {
1004 		if (!wait_for_completion_timeout(&fmc2->dma_ecc_complete,
1005 					msecs_to_jiffies(FMC2_TIMEOUT_MS))) {
1006 			dev_err(fmc2->dev, "ECC DMA timeout\n");
1007 			dmaengine_terminate_all(fmc2->dma_ecc_ch);
1008 			ret = -ETIMEDOUT;
1009 		}
1010 	}
1011 
1012 err_unmap_ecc:
1013 	if (!write_data && !raw)
1014 		dma_unmap_sg(fmc2->dev, fmc2->dma_ecc_sg.sgl,
1015 			     eccsteps, dma_data_dir);
1016 
1017 err_unmap_data:
1018 	dma_unmap_sg(fmc2->dev, fmc2->dma_data_sg.sgl, eccsteps, dma_data_dir);
1019 
1020 	return ret;
1021 }
1022 
1023 static int stm32_fmc2_sequencer_write(struct nand_chip *chip,
1024 				      const u8 *buf, int oob_required,
1025 				      int page, int raw)
1026 {
1027 	struct mtd_info *mtd = nand_to_mtd(chip);
1028 	int ret;
1029 
1030 	/* Configure the sequencer */
1031 	stm32_fmc2_rw_page_init(chip, page, raw, true);
1032 
1033 	/* Write the page */
1034 	ret = stm32_fmc2_xfer(chip, buf, raw, true);
1035 	if (ret)
1036 		return ret;
1037 
1038 	/* Write oob */
1039 	if (oob_required) {
1040 		ret = nand_change_write_column_op(chip, mtd->writesize,
1041 						  chip->oob_poi, mtd->oobsize,
1042 						  false);
1043 		if (ret)
1044 			return ret;
1045 	}
1046 
1047 	return nand_prog_page_end_op(chip);
1048 }
1049 
1050 static int stm32_fmc2_sequencer_write_page(struct nand_chip *chip,
1051 					   const u8 *buf,
1052 					   int oob_required,
1053 					   int page)
1054 {
1055 	int ret;
1056 
1057 	/* Select the target */
1058 	ret = stm32_fmc2_select_chip(chip, chip->cur_cs);
1059 	if (ret)
1060 		return ret;
1061 
1062 	return stm32_fmc2_sequencer_write(chip, buf, oob_required, page, false);
1063 }
1064 
1065 static int stm32_fmc2_sequencer_write_page_raw(struct nand_chip *chip,
1066 					       const u8 *buf,
1067 					       int oob_required,
1068 					       int page)
1069 {
1070 	int ret;
1071 
1072 	/* Select the target */
1073 	ret = stm32_fmc2_select_chip(chip, chip->cur_cs);
1074 	if (ret)
1075 		return ret;
1076 
1077 	return stm32_fmc2_sequencer_write(chip, buf, oob_required, page, true);
1078 }
1079 
1080 /* Get a status indicating which sectors have errors */
1081 static inline u16 stm32_fmc2_get_mapping_status(struct stm32_fmc2_nfc *fmc2)
1082 {
1083 	u32 csqemsr = readl_relaxed(fmc2->io_base + FMC2_CSQEMSR);
1084 
1085 	return csqemsr & FMC2_CSQEMSR_SEM;
1086 }
1087 
1088 static int stm32_fmc2_sequencer_correct(struct nand_chip *chip, u8 *dat,
1089 					u8 *read_ecc, u8 *calc_ecc)
1090 {
1091 	struct mtd_info *mtd = nand_to_mtd(chip);
1092 	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
1093 	int eccbytes = chip->ecc.bytes;
1094 	int eccsteps = chip->ecc.steps;
1095 	int eccstrength = chip->ecc.strength;
1096 	int i, s, eccsize = chip->ecc.size;
1097 	u32 *ecc_sta = (u32 *)fmc2->ecc_buf;
1098 	u16 sta_map = stm32_fmc2_get_mapping_status(fmc2);
1099 	unsigned int max_bitflips = 0;
1100 
1101 	for (i = 0, s = 0; s < eccsteps; s++, i += eccbytes, dat += eccsize) {
1102 		int stat = 0;
1103 
1104 		if (eccstrength == FMC2_ECC_HAM) {
1105 			/* Ecc_sta = FMC2_HECCR */
1106 			if (sta_map & BIT(s)) {
1107 				stm32_fmc2_ham_set_ecc(*ecc_sta, &calc_ecc[i]);
1108 				stat = stm32_fmc2_ham_correct(chip, dat,
1109 							      &read_ecc[i],
1110 							      &calc_ecc[i]);
1111 			}
1112 			ecc_sta++;
1113 		} else {
1114 			/*
1115 			 * Ecc_sta[0] = FMC2_BCHDSR0
1116 			 * Ecc_sta[1] = FMC2_BCHDSR1
1117 			 * Ecc_sta[2] = FMC2_BCHDSR2
1118 			 * Ecc_sta[3] = FMC2_BCHDSR3
1119 			 * Ecc_sta[4] = FMC2_BCHDSR4
1120 			 */
1121 			if (sta_map & BIT(s))
1122 				stat = stm32_fmc2_bch_decode(eccsize, dat,
1123 							     ecc_sta);
1124 			ecc_sta += 5;
1125 		}
1126 
1127 		if (stat == -EBADMSG)
1128 			/* Check for empty pages with bitflips */
1129 			stat = nand_check_erased_ecc_chunk(dat, eccsize,
1130 							   &read_ecc[i],
1131 							   eccbytes,
1132 							   NULL, 0,
1133 							   eccstrength);
1134 
1135 		if (stat < 0) {
1136 			mtd->ecc_stats.failed++;
1137 		} else {
1138 			mtd->ecc_stats.corrected += stat;
1139 			max_bitflips = max_t(unsigned int, max_bitflips, stat);
1140 		}
1141 	}
1142 
1143 	return max_bitflips;
1144 }
1145 
1146 static int stm32_fmc2_sequencer_read_page(struct nand_chip *chip, u8 *buf,
1147 					  int oob_required, int page)
1148 {
1149 	struct mtd_info *mtd = nand_to_mtd(chip);
1150 	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
1151 	u8 *ecc_calc = chip->ecc.calc_buf;
1152 	u8 *ecc_code = chip->ecc.code_buf;
1153 	u16 sta_map;
1154 	int ret;
1155 
1156 	/* Select the target */
1157 	ret = stm32_fmc2_select_chip(chip, chip->cur_cs);
1158 	if (ret)
1159 		return ret;
1160 
1161 	/* Configure the sequencer */
1162 	stm32_fmc2_rw_page_init(chip, page, 0, false);
1163 
1164 	/* Read the page */
1165 	ret = stm32_fmc2_xfer(chip, buf, 0, false);
1166 	if (ret)
1167 		return ret;
1168 
1169 	sta_map = stm32_fmc2_get_mapping_status(fmc2);
1170 
1171 	/* Check if errors happen */
1172 	if (likely(!sta_map)) {
1173 		if (oob_required)
1174 			return nand_change_read_column_op(chip, mtd->writesize,
1175 							  chip->oob_poi,
1176 							  mtd->oobsize, false);
1177 
1178 		return 0;
1179 	}
1180 
1181 	/* Read oob */
1182 	ret = nand_change_read_column_op(chip, mtd->writesize,
1183 					 chip->oob_poi, mtd->oobsize, false);
1184 	if (ret)
1185 		return ret;
1186 
1187 	ret = mtd_ooblayout_get_eccbytes(mtd, ecc_code, chip->oob_poi, 0,
1188 					 chip->ecc.total);
1189 	if (ret)
1190 		return ret;
1191 
1192 	/* Correct data */
1193 	return chip->ecc.correct(chip, buf, ecc_code, ecc_calc);
1194 }
1195 
1196 static int stm32_fmc2_sequencer_read_page_raw(struct nand_chip *chip, u8 *buf,
1197 					      int oob_required, int page)
1198 {
1199 	struct mtd_info *mtd = nand_to_mtd(chip);
1200 	int ret;
1201 
1202 	/* Select the target */
1203 	ret = stm32_fmc2_select_chip(chip, chip->cur_cs);
1204 	if (ret)
1205 		return ret;
1206 
1207 	/* Configure the sequencer */
1208 	stm32_fmc2_rw_page_init(chip, page, 1, false);
1209 
1210 	/* Read the page */
1211 	ret = stm32_fmc2_xfer(chip, buf, 1, false);
1212 	if (ret)
1213 		return ret;
1214 
1215 	/* Read oob */
1216 	if (oob_required)
1217 		return nand_change_read_column_op(chip, mtd->writesize,
1218 						  chip->oob_poi, mtd->oobsize,
1219 						  false);
1220 
1221 	return 0;
1222 }
1223 
1224 static irqreturn_t stm32_fmc2_irq(int irq, void *dev_id)
1225 {
1226 	struct stm32_fmc2_nfc *fmc2 = (struct stm32_fmc2_nfc *)dev_id;
1227 
1228 	if (fmc2->irq_state == FMC2_IRQ_SEQ)
1229 		/* Sequencer is used */
1230 		stm32_fmc2_disable_seq_irq(fmc2);
1231 	else if (fmc2->irq_state == FMC2_IRQ_BCH)
1232 		/* BCH is used */
1233 		stm32_fmc2_disable_bch_irq(fmc2);
1234 
1235 	complete(&fmc2->complete);
1236 
1237 	return IRQ_HANDLED;
1238 }
1239 
1240 static void stm32_fmc2_read_data(struct nand_chip *chip, void *buf,
1241 				 unsigned int len, bool force_8bit)
1242 {
1243 	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
1244 	void __iomem *io_addr_r = fmc2->data_base[fmc2->cs_sel];
1245 
1246 	if (force_8bit && chip->options & NAND_BUSWIDTH_16)
1247 		/* Reconfigure bus width to 8-bit */
1248 		stm32_fmc2_set_buswidth_16(fmc2, false);
1249 
1250 	if (!IS_ALIGNED((uintptr_t)buf, sizeof(u32))) {
1251 		if (!IS_ALIGNED((uintptr_t)buf, sizeof(u16)) && len) {
1252 			*(u8 *)buf = readb_relaxed(io_addr_r);
1253 			buf += sizeof(u8);
1254 			len -= sizeof(u8);
1255 		}
1256 
1257 		if (!IS_ALIGNED((uintptr_t)buf, sizeof(u32)) &&
1258 		    len >= sizeof(u16)) {
1259 			*(u16 *)buf = readw_relaxed(io_addr_r);
1260 			buf += sizeof(u16);
1261 			len -= sizeof(u16);
1262 		}
1263 	}
1264 
1265 	/* Buf is aligned */
1266 	while (len >= sizeof(u32)) {
1267 		*(u32 *)buf = readl_relaxed(io_addr_r);
1268 		buf += sizeof(u32);
1269 		len -= sizeof(u32);
1270 	}
1271 
1272 	/* Read remaining bytes */
1273 	if (len >= sizeof(u16)) {
1274 		*(u16 *)buf = readw_relaxed(io_addr_r);
1275 		buf += sizeof(u16);
1276 		len -= sizeof(u16);
1277 	}
1278 
1279 	if (len)
1280 		*(u8 *)buf = readb_relaxed(io_addr_r);
1281 
1282 	if (force_8bit && chip->options & NAND_BUSWIDTH_16)
1283 		/* Reconfigure bus width to 16-bit */
1284 		stm32_fmc2_set_buswidth_16(fmc2, true);
1285 }
1286 
1287 static void stm32_fmc2_write_data(struct nand_chip *chip, const void *buf,
1288 				  unsigned int len, bool force_8bit)
1289 {
1290 	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
1291 	void __iomem *io_addr_w = fmc2->data_base[fmc2->cs_sel];
1292 
1293 	if (force_8bit && chip->options & NAND_BUSWIDTH_16)
1294 		/* Reconfigure bus width to 8-bit */
1295 		stm32_fmc2_set_buswidth_16(fmc2, false);
1296 
1297 	if (!IS_ALIGNED((uintptr_t)buf, sizeof(u32))) {
1298 		if (!IS_ALIGNED((uintptr_t)buf, sizeof(u16)) && len) {
1299 			writeb_relaxed(*(u8 *)buf, io_addr_w);
1300 			buf += sizeof(u8);
1301 			len -= sizeof(u8);
1302 		}
1303 
1304 		if (!IS_ALIGNED((uintptr_t)buf, sizeof(u32)) &&
1305 		    len >= sizeof(u16)) {
1306 			writew_relaxed(*(u16 *)buf, io_addr_w);
1307 			buf += sizeof(u16);
1308 			len -= sizeof(u16);
1309 		}
1310 	}
1311 
1312 	/* Buf is aligned */
1313 	while (len >= sizeof(u32)) {
1314 		writel_relaxed(*(u32 *)buf, io_addr_w);
1315 		buf += sizeof(u32);
1316 		len -= sizeof(u32);
1317 	}
1318 
1319 	/* Write remaining bytes */
1320 	if (len >= sizeof(u16)) {
1321 		writew_relaxed(*(u16 *)buf, io_addr_w);
1322 		buf += sizeof(u16);
1323 		len -= sizeof(u16);
1324 	}
1325 
1326 	if (len)
1327 		writeb_relaxed(*(u8 *)buf, io_addr_w);
1328 
1329 	if (force_8bit && chip->options & NAND_BUSWIDTH_16)
1330 		/* Reconfigure bus width to 16-bit */
1331 		stm32_fmc2_set_buswidth_16(fmc2, true);
1332 }
1333 
1334 static int stm32_fmc2_waitrdy(struct nand_chip *chip, unsigned long timeout_ms)
1335 {
1336 	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
1337 	const struct nand_sdr_timings *timings;
1338 	u32 isr, sr;
1339 
1340 	/* Check if there is no pending requests to the NAND flash */
1341 	if (readl_relaxed_poll_timeout_atomic(fmc2->io_base + FMC2_SR, sr,
1342 					      sr & FMC2_SR_NWRF, 1,
1343 					      FMC2_TIMEOUT_US))
1344 		dev_warn(fmc2->dev, "Waitrdy timeout\n");
1345 
1346 	/* Wait tWB before R/B# signal is low */
1347 	timings = nand_get_sdr_timings(&chip->data_interface);
1348 	ndelay(PSEC_TO_NSEC(timings->tWB_max));
1349 
1350 	/* R/B# signal is low, clear high level flag */
1351 	writel_relaxed(FMC2_ICR_CIHLF, fmc2->io_base + FMC2_ICR);
1352 
1353 	/* Wait R/B# signal is high */
1354 	return readl_relaxed_poll_timeout_atomic(fmc2->io_base + FMC2_ISR,
1355 						 isr, isr & FMC2_ISR_IHLF,
1356 						 5, 1000 * timeout_ms);
1357 }
1358 
1359 static int stm32_fmc2_exec_op(struct nand_chip *chip,
1360 			      const struct nand_operation *op,
1361 			      bool check_only)
1362 {
1363 	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
1364 	const struct nand_op_instr *instr = NULL;
1365 	unsigned int op_id, i;
1366 	int ret;
1367 
1368 	ret = stm32_fmc2_select_chip(chip, op->cs);
1369 	if (ret)
1370 		return ret;
1371 
1372 	if (check_only)
1373 		return ret;
1374 
1375 	for (op_id = 0; op_id < op->ninstrs; op_id++) {
1376 		instr = &op->instrs[op_id];
1377 
1378 		switch (instr->type) {
1379 		case NAND_OP_CMD_INSTR:
1380 			writeb_relaxed(instr->ctx.cmd.opcode,
1381 				       fmc2->cmd_base[fmc2->cs_sel]);
1382 			break;
1383 
1384 		case NAND_OP_ADDR_INSTR:
1385 			for (i = 0; i < instr->ctx.addr.naddrs; i++)
1386 				writeb_relaxed(instr->ctx.addr.addrs[i],
1387 					       fmc2->addr_base[fmc2->cs_sel]);
1388 			break;
1389 
1390 		case NAND_OP_DATA_IN_INSTR:
1391 			stm32_fmc2_read_data(chip, instr->ctx.data.buf.in,
1392 					     instr->ctx.data.len,
1393 					     instr->ctx.data.force_8bit);
1394 			break;
1395 
1396 		case NAND_OP_DATA_OUT_INSTR:
1397 			stm32_fmc2_write_data(chip, instr->ctx.data.buf.out,
1398 					      instr->ctx.data.len,
1399 					      instr->ctx.data.force_8bit);
1400 			break;
1401 
1402 		case NAND_OP_WAITRDY_INSTR:
1403 			ret = stm32_fmc2_waitrdy(chip,
1404 						 instr->ctx.waitrdy.timeout_ms);
1405 			break;
1406 		}
1407 	}
1408 
1409 	return ret;
1410 }
1411 
1412 /* Controller initialization */
1413 static void stm32_fmc2_init(struct stm32_fmc2_nfc *fmc2)
1414 {
1415 	u32 pcr = readl_relaxed(fmc2->io_base + FMC2_PCR);
1416 	u32 bcr1 = readl_relaxed(fmc2->io_base + FMC2_BCR1);
1417 
1418 	/* Set CS used to undefined */
1419 	fmc2->cs_sel = -1;
1420 
1421 	/* Enable wait feature and nand flash memory bank */
1422 	pcr |= FMC2_PCR_PWAITEN;
1423 	pcr |= FMC2_PCR_PBKEN;
1424 
1425 	/* Set buswidth to 8 bits mode for identification */
1426 	pcr &= ~FMC2_PCR_PWID_MASK;
1427 
1428 	/* ECC logic is disabled */
1429 	pcr &= ~FMC2_PCR_ECCEN;
1430 
1431 	/* Default mode */
1432 	pcr &= ~FMC2_PCR_ECCALG;
1433 	pcr &= ~FMC2_PCR_BCHECC;
1434 	pcr &= ~FMC2_PCR_WEN;
1435 
1436 	/* Set default ECC sector size */
1437 	pcr &= ~FMC2_PCR_ECCSS_MASK;
1438 	pcr |= FMC2_PCR_ECCSS(FMC2_PCR_ECCSS_2048);
1439 
1440 	/* Set default tclr/tar timings */
1441 	pcr &= ~FMC2_PCR_TCLR_MASK;
1442 	pcr |= FMC2_PCR_TCLR(FMC2_PCR_TCLR_DEFAULT);
1443 	pcr &= ~FMC2_PCR_TAR_MASK;
1444 	pcr |= FMC2_PCR_TAR(FMC2_PCR_TAR_DEFAULT);
1445 
1446 	/* Enable FMC2 controller */
1447 	bcr1 |= FMC2_BCR1_FMC2EN;
1448 
1449 	writel_relaxed(bcr1, fmc2->io_base + FMC2_BCR1);
1450 	writel_relaxed(pcr, fmc2->io_base + FMC2_PCR);
1451 	writel_relaxed(FMC2_PMEM_DEFAULT, fmc2->io_base + FMC2_PMEM);
1452 	writel_relaxed(FMC2_PATT_DEFAULT, fmc2->io_base + FMC2_PATT);
1453 }
1454 
1455 /* Controller timings */
1456 static void stm32_fmc2_calc_timings(struct nand_chip *chip,
1457 				    const struct nand_sdr_timings *sdrt)
1458 {
1459 	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
1460 	struct stm32_fmc2_nand *nand = to_fmc2_nand(chip);
1461 	struct stm32_fmc2_timings *tims = &nand->timings;
1462 	unsigned long hclk = clk_get_rate(fmc2->clk);
1463 	unsigned long hclkp = NSEC_PER_SEC / (hclk / 1000);
1464 	unsigned long timing, tar, tclr, thiz, twait;
1465 	unsigned long tset_mem, tset_att, thold_mem, thold_att;
1466 
1467 	tar = max_t(unsigned long, hclkp, sdrt->tAR_min);
1468 	timing = DIV_ROUND_UP(tar, hclkp) - 1;
1469 	tims->tar = min_t(unsigned long, timing, FMC2_PCR_TIMING_MASK);
1470 
1471 	tclr = max_t(unsigned long, hclkp, sdrt->tCLR_min);
1472 	timing = DIV_ROUND_UP(tclr, hclkp) - 1;
1473 	tims->tclr = min_t(unsigned long, timing, FMC2_PCR_TIMING_MASK);
1474 
1475 	tims->thiz = FMC2_THIZ;
1476 	thiz = (tims->thiz + 1) * hclkp;
1477 
1478 	/*
1479 	 * tWAIT > tRP
1480 	 * tWAIT > tWP
1481 	 * tWAIT > tREA + tIO
1482 	 */
1483 	twait = max_t(unsigned long, hclkp, sdrt->tRP_min);
1484 	twait = max_t(unsigned long, twait, sdrt->tWP_min);
1485 	twait = max_t(unsigned long, twait, sdrt->tREA_max + FMC2_TIO);
1486 	timing = DIV_ROUND_UP(twait, hclkp);
1487 	tims->twait = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);
1488 
1489 	/*
1490 	 * tSETUP_MEM > tCS - tWAIT
1491 	 * tSETUP_MEM > tALS - tWAIT
1492 	 * tSETUP_MEM > tDS - (tWAIT - tHIZ)
1493 	 */
1494 	tset_mem = hclkp;
1495 	if (sdrt->tCS_min > twait && (tset_mem < sdrt->tCS_min - twait))
1496 		tset_mem = sdrt->tCS_min - twait;
1497 	if (sdrt->tALS_min > twait && (tset_mem < sdrt->tALS_min - twait))
1498 		tset_mem = sdrt->tALS_min - twait;
1499 	if (twait > thiz && (sdrt->tDS_min > twait - thiz) &&
1500 	    (tset_mem < sdrt->tDS_min - (twait - thiz)))
1501 		tset_mem = sdrt->tDS_min - (twait - thiz);
1502 	timing = DIV_ROUND_UP(tset_mem, hclkp);
1503 	tims->tset_mem = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);
1504 
1505 	/*
1506 	 * tHOLD_MEM > tCH
1507 	 * tHOLD_MEM > tREH - tSETUP_MEM
1508 	 * tHOLD_MEM > max(tRC, tWC) - (tSETUP_MEM + tWAIT)
1509 	 */
1510 	thold_mem = max_t(unsigned long, hclkp, sdrt->tCH_min);
1511 	if (sdrt->tREH_min > tset_mem &&
1512 	    (thold_mem < sdrt->tREH_min - tset_mem))
1513 		thold_mem = sdrt->tREH_min - tset_mem;
1514 	if ((sdrt->tRC_min > tset_mem + twait) &&
1515 	    (thold_mem < sdrt->tRC_min - (tset_mem + twait)))
1516 		thold_mem = sdrt->tRC_min - (tset_mem + twait);
1517 	if ((sdrt->tWC_min > tset_mem + twait) &&
1518 	    (thold_mem < sdrt->tWC_min - (tset_mem + twait)))
1519 		thold_mem = sdrt->tWC_min - (tset_mem + twait);
1520 	timing = DIV_ROUND_UP(thold_mem, hclkp);
1521 	tims->thold_mem = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);
1522 
1523 	/*
1524 	 * tSETUP_ATT > tCS - tWAIT
1525 	 * tSETUP_ATT > tCLS - tWAIT
1526 	 * tSETUP_ATT > tALS - tWAIT
1527 	 * tSETUP_ATT > tRHW - tHOLD_MEM
1528 	 * tSETUP_ATT > tDS - (tWAIT - tHIZ)
1529 	 */
1530 	tset_att = hclkp;
1531 	if (sdrt->tCS_min > twait && (tset_att < sdrt->tCS_min - twait))
1532 		tset_att = sdrt->tCS_min - twait;
1533 	if (sdrt->tCLS_min > twait && (tset_att < sdrt->tCLS_min - twait))
1534 		tset_att = sdrt->tCLS_min - twait;
1535 	if (sdrt->tALS_min > twait && (tset_att < sdrt->tALS_min - twait))
1536 		tset_att = sdrt->tALS_min - twait;
1537 	if (sdrt->tRHW_min > thold_mem &&
1538 	    (tset_att < sdrt->tRHW_min - thold_mem))
1539 		tset_att = sdrt->tRHW_min - thold_mem;
1540 	if (twait > thiz && (sdrt->tDS_min > twait - thiz) &&
1541 	    (tset_att < sdrt->tDS_min - (twait - thiz)))
1542 		tset_att = sdrt->tDS_min - (twait - thiz);
1543 	timing = DIV_ROUND_UP(tset_att, hclkp);
1544 	tims->tset_att = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);
1545 
1546 	/*
1547 	 * tHOLD_ATT > tALH
1548 	 * tHOLD_ATT > tCH
1549 	 * tHOLD_ATT > tCLH
1550 	 * tHOLD_ATT > tCOH
1551 	 * tHOLD_ATT > tDH
1552 	 * tHOLD_ATT > tWB + tIO + tSYNC - tSETUP_MEM
1553 	 * tHOLD_ATT > tADL - tSETUP_MEM
1554 	 * tHOLD_ATT > tWH - tSETUP_MEM
1555 	 * tHOLD_ATT > tWHR - tSETUP_MEM
1556 	 * tHOLD_ATT > tRC - (tSETUP_ATT + tWAIT)
1557 	 * tHOLD_ATT > tWC - (tSETUP_ATT + tWAIT)
1558 	 */
1559 	thold_att = max_t(unsigned long, hclkp, sdrt->tALH_min);
1560 	thold_att = max_t(unsigned long, thold_att, sdrt->tCH_min);
1561 	thold_att = max_t(unsigned long, thold_att, sdrt->tCLH_min);
1562 	thold_att = max_t(unsigned long, thold_att, sdrt->tCOH_min);
1563 	thold_att = max_t(unsigned long, thold_att, sdrt->tDH_min);
1564 	if ((sdrt->tWB_max + FMC2_TIO + FMC2_TSYNC > tset_mem) &&
1565 	    (thold_att < sdrt->tWB_max + FMC2_TIO + FMC2_TSYNC - tset_mem))
1566 		thold_att = sdrt->tWB_max + FMC2_TIO + FMC2_TSYNC - tset_mem;
1567 	if (sdrt->tADL_min > tset_mem &&
1568 	    (thold_att < sdrt->tADL_min - tset_mem))
1569 		thold_att = sdrt->tADL_min - tset_mem;
1570 	if (sdrt->tWH_min > tset_mem &&
1571 	    (thold_att < sdrt->tWH_min - tset_mem))
1572 		thold_att = sdrt->tWH_min - tset_mem;
1573 	if (sdrt->tWHR_min > tset_mem &&
1574 	    (thold_att < sdrt->tWHR_min - tset_mem))
1575 		thold_att = sdrt->tWHR_min - tset_mem;
1576 	if ((sdrt->tRC_min > tset_att + twait) &&
1577 	    (thold_att < sdrt->tRC_min - (tset_att + twait)))
1578 		thold_att = sdrt->tRC_min - (tset_att + twait);
1579 	if ((sdrt->tWC_min > tset_att + twait) &&
1580 	    (thold_att < sdrt->tWC_min - (tset_att + twait)))
1581 		thold_att = sdrt->tWC_min - (tset_att + twait);
1582 	timing = DIV_ROUND_UP(thold_att, hclkp);
1583 	tims->thold_att = clamp_val(timing, 1, FMC2_PMEM_PATT_TIMING_MASK);
1584 }
1585 
1586 static int stm32_fmc2_setup_interface(struct nand_chip *chip, int chipnr,
1587 				      const struct nand_data_interface *conf)
1588 {
1589 	const struct nand_sdr_timings *sdrt;
1590 
1591 	sdrt = nand_get_sdr_timings(conf);
1592 	if (IS_ERR(sdrt))
1593 		return PTR_ERR(sdrt);
1594 
1595 	if (chipnr == NAND_DATA_IFACE_CHECK_ONLY)
1596 		return 0;
1597 
1598 	stm32_fmc2_calc_timings(chip, sdrt);
1599 
1600 	/* Apply timings */
1601 	stm32_fmc2_timings_init(chip);
1602 
1603 	return 0;
1604 }
1605 
1606 /* DMA configuration */
1607 static int stm32_fmc2_dma_setup(struct stm32_fmc2_nfc *fmc2)
1608 {
1609 	int ret;
1610 
1611 	fmc2->dma_tx_ch = dma_request_slave_channel(fmc2->dev, "tx");
1612 	fmc2->dma_rx_ch = dma_request_slave_channel(fmc2->dev, "rx");
1613 	fmc2->dma_ecc_ch = dma_request_slave_channel(fmc2->dev, "ecc");
1614 
1615 	if (!fmc2->dma_tx_ch || !fmc2->dma_rx_ch || !fmc2->dma_ecc_ch) {
1616 		dev_warn(fmc2->dev, "DMAs not defined in the device tree, polling mode is used\n");
1617 		return 0;
1618 	}
1619 
1620 	ret = sg_alloc_table(&fmc2->dma_ecc_sg, FMC2_MAX_SG, GFP_KERNEL);
1621 	if (ret)
1622 		return ret;
1623 
1624 	/* Allocate a buffer to store ECC status registers */
1625 	fmc2->ecc_buf = devm_kzalloc(fmc2->dev, FMC2_MAX_ECC_BUF_LEN,
1626 				     GFP_KERNEL);
1627 	if (!fmc2->ecc_buf)
1628 		return -ENOMEM;
1629 
1630 	ret = sg_alloc_table(&fmc2->dma_data_sg, FMC2_MAX_SG, GFP_KERNEL);
1631 	if (ret)
1632 		return ret;
1633 
1634 	init_completion(&fmc2->dma_data_complete);
1635 	init_completion(&fmc2->dma_ecc_complete);
1636 
1637 	return 0;
1638 }
1639 
1640 /* NAND callbacks setup */
1641 static void stm32_fmc2_nand_callbacks_setup(struct nand_chip *chip)
1642 {
1643 	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
1644 
1645 	/*
1646 	 * Specific callbacks to read/write a page depending on
1647 	 * the mode (polling/sequencer) and the algo used (Hamming, BCH).
1648 	 */
1649 	if (fmc2->dma_tx_ch && fmc2->dma_rx_ch && fmc2->dma_ecc_ch) {
1650 		/* DMA => use sequencer mode callbacks */
1651 		chip->ecc.correct = stm32_fmc2_sequencer_correct;
1652 		chip->ecc.write_page = stm32_fmc2_sequencer_write_page;
1653 		chip->ecc.read_page = stm32_fmc2_sequencer_read_page;
1654 		chip->ecc.write_page_raw = stm32_fmc2_sequencer_write_page_raw;
1655 		chip->ecc.read_page_raw = stm32_fmc2_sequencer_read_page_raw;
1656 	} else {
1657 		/* No DMA => use polling mode callbacks */
1658 		chip->ecc.hwctl = stm32_fmc2_hwctl;
1659 		if (chip->ecc.strength == FMC2_ECC_HAM) {
1660 			/* Hamming is used */
1661 			chip->ecc.calculate = stm32_fmc2_ham_calculate;
1662 			chip->ecc.correct = stm32_fmc2_ham_correct;
1663 			chip->ecc.options |= NAND_ECC_GENERIC_ERASED_CHECK;
1664 		} else {
1665 			/* BCH is used */
1666 			chip->ecc.calculate = stm32_fmc2_bch_calculate;
1667 			chip->ecc.correct = stm32_fmc2_bch_correct;
1668 			chip->ecc.read_page = stm32_fmc2_read_page;
1669 		}
1670 	}
1671 
1672 	/* Specific configurations depending on the algo used */
1673 	if (chip->ecc.strength == FMC2_ECC_HAM)
1674 		chip->ecc.bytes = chip->options & NAND_BUSWIDTH_16 ? 4 : 3;
1675 	else if (chip->ecc.strength == FMC2_ECC_BCH8)
1676 		chip->ecc.bytes = chip->options & NAND_BUSWIDTH_16 ? 14 : 13;
1677 	else
1678 		chip->ecc.bytes = chip->options & NAND_BUSWIDTH_16 ? 8 : 7;
1679 }
1680 
1681 /* FMC2 layout */
1682 static int stm32_fmc2_nand_ooblayout_ecc(struct mtd_info *mtd, int section,
1683 					 struct mtd_oob_region *oobregion)
1684 {
1685 	struct nand_chip *chip = mtd_to_nand(mtd);
1686 	struct nand_ecc_ctrl *ecc = &chip->ecc;
1687 
1688 	if (section)
1689 		return -ERANGE;
1690 
1691 	oobregion->length = ecc->total;
1692 	oobregion->offset = FMC2_BBM_LEN;
1693 
1694 	return 0;
1695 }
1696 
1697 static int stm32_fmc2_nand_ooblayout_free(struct mtd_info *mtd, int section,
1698 					  struct mtd_oob_region *oobregion)
1699 {
1700 	struct nand_chip *chip = mtd_to_nand(mtd);
1701 	struct nand_ecc_ctrl *ecc = &chip->ecc;
1702 
1703 	if (section)
1704 		return -ERANGE;
1705 
1706 	oobregion->length = mtd->oobsize - ecc->total - FMC2_BBM_LEN;
1707 	oobregion->offset = ecc->total + FMC2_BBM_LEN;
1708 
1709 	return 0;
1710 }
1711 
1712 static const struct mtd_ooblayout_ops stm32_fmc2_nand_ooblayout_ops = {
1713 	.ecc = stm32_fmc2_nand_ooblayout_ecc,
1714 	.free = stm32_fmc2_nand_ooblayout_free,
1715 };
1716 
1717 /* FMC2 caps */
1718 static int stm32_fmc2_calc_ecc_bytes(int step_size, int strength)
1719 {
1720 	/* Hamming */
1721 	if (strength == FMC2_ECC_HAM)
1722 		return 4;
1723 
1724 	/* BCH8 */
1725 	if (strength == FMC2_ECC_BCH8)
1726 		return 14;
1727 
1728 	/* BCH4 */
1729 	return 8;
1730 }
1731 
1732 NAND_ECC_CAPS_SINGLE(stm32_fmc2_ecc_caps, stm32_fmc2_calc_ecc_bytes,
1733 		     FMC2_ECC_STEP_SIZE,
1734 		     FMC2_ECC_HAM, FMC2_ECC_BCH4, FMC2_ECC_BCH8);
1735 
1736 /* FMC2 controller ops */
1737 static int stm32_fmc2_attach_chip(struct nand_chip *chip)
1738 {
1739 	struct stm32_fmc2_nfc *fmc2 = to_stm32_nfc(chip->controller);
1740 	struct mtd_info *mtd = nand_to_mtd(chip);
1741 	int ret;
1742 
1743 	/*
1744 	 * Only NAND_ECC_HW mode is actually supported
1745 	 * Hamming => ecc.strength = 1
1746 	 * BCH4 => ecc.strength = 4
1747 	 * BCH8 => ecc.strength = 8
1748 	 * ECC sector size = 512
1749 	 */
1750 	if (chip->ecc.mode != NAND_ECC_HW) {
1751 		dev_err(fmc2->dev, "nand_ecc_mode is not well defined in the DT\n");
1752 		return -EINVAL;
1753 	}
1754 
1755 	ret = nand_ecc_choose_conf(chip, &stm32_fmc2_ecc_caps,
1756 				   mtd->oobsize - FMC2_BBM_LEN);
1757 	if (ret) {
1758 		dev_err(fmc2->dev, "no valid ECC settings set\n");
1759 		return ret;
1760 	}
1761 
1762 	if (mtd->writesize / chip->ecc.size > FMC2_MAX_SG) {
1763 		dev_err(fmc2->dev, "nand page size is not supported\n");
1764 		return -EINVAL;
1765 	}
1766 
1767 	if (chip->bbt_options & NAND_BBT_USE_FLASH)
1768 		chip->bbt_options |= NAND_BBT_NO_OOB;
1769 
1770 	/* NAND callbacks setup */
1771 	stm32_fmc2_nand_callbacks_setup(chip);
1772 
1773 	/* Define ECC layout */
1774 	mtd_set_ooblayout(mtd, &stm32_fmc2_nand_ooblayout_ops);
1775 
1776 	/* Configure bus width to 16-bit */
1777 	if (chip->options & NAND_BUSWIDTH_16)
1778 		stm32_fmc2_set_buswidth_16(fmc2, true);
1779 
1780 	return 0;
1781 }
1782 
1783 static const struct nand_controller_ops stm32_fmc2_nand_controller_ops = {
1784 	.attach_chip = stm32_fmc2_attach_chip,
1785 	.exec_op = stm32_fmc2_exec_op,
1786 	.setup_data_interface = stm32_fmc2_setup_interface,
1787 };
1788 
1789 /* FMC2 probe */
1790 static int stm32_fmc2_parse_child(struct stm32_fmc2_nfc *fmc2,
1791 				  struct device_node *dn)
1792 {
1793 	struct stm32_fmc2_nand *nand = &fmc2->nand;
1794 	u32 cs;
1795 	int ret, i;
1796 
1797 	if (!of_get_property(dn, "reg", &nand->ncs))
1798 		return -EINVAL;
1799 
1800 	nand->ncs /= sizeof(u32);
1801 	if (!nand->ncs) {
1802 		dev_err(fmc2->dev, "invalid reg property size\n");
1803 		return -EINVAL;
1804 	}
1805 
1806 	for (i = 0; i < nand->ncs; i++) {
1807 		ret = of_property_read_u32_index(dn, "reg", i, &cs);
1808 		if (ret) {
1809 			dev_err(fmc2->dev, "could not retrieve reg property: %d\n",
1810 				ret);
1811 			return ret;
1812 		}
1813 
1814 		if (cs > FMC2_MAX_CE) {
1815 			dev_err(fmc2->dev, "invalid reg value: %d\n", cs);
1816 			return -EINVAL;
1817 		}
1818 
1819 		if (fmc2->cs_assigned & BIT(cs)) {
1820 			dev_err(fmc2->dev, "cs already assigned: %d\n", cs);
1821 			return -EINVAL;
1822 		}
1823 
1824 		fmc2->cs_assigned |= BIT(cs);
1825 		nand->cs_used[i] = cs;
1826 	}
1827 
1828 	nand_set_flash_node(&nand->chip, dn);
1829 
1830 	return 0;
1831 }
1832 
1833 static int stm32_fmc2_parse_dt(struct stm32_fmc2_nfc *fmc2)
1834 {
1835 	struct device_node *dn = fmc2->dev->of_node;
1836 	struct device_node *child;
1837 	int nchips = of_get_child_count(dn);
1838 	int ret = 0;
1839 
1840 	if (!nchips) {
1841 		dev_err(fmc2->dev, "NAND chip not defined\n");
1842 		return -EINVAL;
1843 	}
1844 
1845 	if (nchips > 1) {
1846 		dev_err(fmc2->dev, "too many NAND chips defined\n");
1847 		return -EINVAL;
1848 	}
1849 
1850 	for_each_child_of_node(dn, child) {
1851 		ret = stm32_fmc2_parse_child(fmc2, child);
1852 		if (ret < 0) {
1853 			of_node_put(child);
1854 			return ret;
1855 		}
1856 	}
1857 
1858 	return ret;
1859 }
1860 
1861 static int stm32_fmc2_probe(struct platform_device *pdev)
1862 {
1863 	struct device *dev = &pdev->dev;
1864 	struct reset_control *rstc;
1865 	struct stm32_fmc2_nfc *fmc2;
1866 	struct stm32_fmc2_nand *nand;
1867 	struct resource *res;
1868 	struct mtd_info *mtd;
1869 	struct nand_chip *chip;
1870 	int chip_cs, mem_region, ret, irq;
1871 
1872 	fmc2 = devm_kzalloc(dev, sizeof(*fmc2), GFP_KERNEL);
1873 	if (!fmc2)
1874 		return -ENOMEM;
1875 
1876 	fmc2->dev = dev;
1877 	nand_controller_init(&fmc2->base);
1878 	fmc2->base.ops = &stm32_fmc2_nand_controller_ops;
1879 
1880 	ret = stm32_fmc2_parse_dt(fmc2);
1881 	if (ret)
1882 		return ret;
1883 
1884 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1885 	fmc2->io_base = devm_ioremap_resource(dev, res);
1886 	if (IS_ERR(fmc2->io_base))
1887 		return PTR_ERR(fmc2->io_base);
1888 
1889 	fmc2->io_phys_addr = res->start;
1890 
1891 	for (chip_cs = 0, mem_region = 1; chip_cs < FMC2_MAX_CE;
1892 	     chip_cs++, mem_region += 3) {
1893 		if (!(fmc2->cs_assigned & BIT(chip_cs)))
1894 			continue;
1895 
1896 		res = platform_get_resource(pdev, IORESOURCE_MEM, mem_region);
1897 		fmc2->data_base[chip_cs] = devm_ioremap_resource(dev, res);
1898 		if (IS_ERR(fmc2->data_base[chip_cs]))
1899 			return PTR_ERR(fmc2->data_base[chip_cs]);
1900 
1901 		fmc2->data_phys_addr[chip_cs] = res->start;
1902 
1903 		res = platform_get_resource(pdev, IORESOURCE_MEM,
1904 					    mem_region + 1);
1905 		fmc2->cmd_base[chip_cs] = devm_ioremap_resource(dev, res);
1906 		if (IS_ERR(fmc2->cmd_base[chip_cs]))
1907 			return PTR_ERR(fmc2->cmd_base[chip_cs]);
1908 
1909 		res = platform_get_resource(pdev, IORESOURCE_MEM,
1910 					    mem_region + 2);
1911 		fmc2->addr_base[chip_cs] = devm_ioremap_resource(dev, res);
1912 		if (IS_ERR(fmc2->addr_base[chip_cs]))
1913 			return PTR_ERR(fmc2->addr_base[chip_cs]);
1914 	}
1915 
1916 	irq = platform_get_irq(pdev, 0);
1917 	if (irq < 0)
1918 		return irq;
1919 
1920 	ret = devm_request_irq(dev, irq, stm32_fmc2_irq, 0,
1921 			       dev_name(dev), fmc2);
1922 	if (ret) {
1923 		dev_err(dev, "failed to request irq\n");
1924 		return ret;
1925 	}
1926 
1927 	init_completion(&fmc2->complete);
1928 
1929 	fmc2->clk = devm_clk_get(dev, NULL);
1930 	if (IS_ERR(fmc2->clk))
1931 		return PTR_ERR(fmc2->clk);
1932 
1933 	ret = clk_prepare_enable(fmc2->clk);
1934 	if (ret) {
1935 		dev_err(dev, "can not enable the clock\n");
1936 		return ret;
1937 	}
1938 
1939 	rstc = devm_reset_control_get(dev, NULL);
1940 	if (!IS_ERR(rstc)) {
1941 		reset_control_assert(rstc);
1942 		reset_control_deassert(rstc);
1943 	}
1944 
1945 	/* DMA setup */
1946 	ret = stm32_fmc2_dma_setup(fmc2);
1947 	if (ret)
1948 		return ret;
1949 
1950 	/* FMC2 init routine */
1951 	stm32_fmc2_init(fmc2);
1952 
1953 	nand = &fmc2->nand;
1954 	chip = &nand->chip;
1955 	mtd = nand_to_mtd(chip);
1956 	mtd->dev.parent = dev;
1957 
1958 	chip->controller = &fmc2->base;
1959 	chip->options |= NAND_BUSWIDTH_AUTO | NAND_NO_SUBPAGE_WRITE |
1960 			 NAND_USE_BOUNCE_BUFFER;
1961 
1962 	/* Default ECC settings */
1963 	chip->ecc.mode = NAND_ECC_HW;
1964 	chip->ecc.size = FMC2_ECC_STEP_SIZE;
1965 	chip->ecc.strength = FMC2_ECC_BCH8;
1966 
1967 	/* Scan to find existence of the device */
1968 	ret = nand_scan(chip, nand->ncs);
1969 	if (ret)
1970 		goto err_scan;
1971 
1972 	ret = mtd_device_register(mtd, NULL, 0);
1973 	if (ret)
1974 		goto err_device_register;
1975 
1976 	platform_set_drvdata(pdev, fmc2);
1977 
1978 	return 0;
1979 
1980 err_device_register:
1981 	nand_cleanup(chip);
1982 
1983 err_scan:
1984 	if (fmc2->dma_ecc_ch)
1985 		dma_release_channel(fmc2->dma_ecc_ch);
1986 	if (fmc2->dma_tx_ch)
1987 		dma_release_channel(fmc2->dma_tx_ch);
1988 	if (fmc2->dma_rx_ch)
1989 		dma_release_channel(fmc2->dma_rx_ch);
1990 
1991 	sg_free_table(&fmc2->dma_data_sg);
1992 	sg_free_table(&fmc2->dma_ecc_sg);
1993 
1994 	clk_disable_unprepare(fmc2->clk);
1995 
1996 	return ret;
1997 }
1998 
1999 static int stm32_fmc2_remove(struct platform_device *pdev)
2000 {
2001 	struct stm32_fmc2_nfc *fmc2 = platform_get_drvdata(pdev);
2002 	struct stm32_fmc2_nand *nand = &fmc2->nand;
2003 
2004 	nand_release(&nand->chip);
2005 
2006 	if (fmc2->dma_ecc_ch)
2007 		dma_release_channel(fmc2->dma_ecc_ch);
2008 	if (fmc2->dma_tx_ch)
2009 		dma_release_channel(fmc2->dma_tx_ch);
2010 	if (fmc2->dma_rx_ch)
2011 		dma_release_channel(fmc2->dma_rx_ch);
2012 
2013 	sg_free_table(&fmc2->dma_data_sg);
2014 	sg_free_table(&fmc2->dma_ecc_sg);
2015 
2016 	clk_disable_unprepare(fmc2->clk);
2017 
2018 	return 0;
2019 }
2020 
2021 static int __maybe_unused stm32_fmc2_suspend(struct device *dev)
2022 {
2023 	struct stm32_fmc2_nfc *fmc2 = dev_get_drvdata(dev);
2024 
2025 	clk_disable_unprepare(fmc2->clk);
2026 
2027 	pinctrl_pm_select_sleep_state(dev);
2028 
2029 	return 0;
2030 }
2031 
2032 static int __maybe_unused stm32_fmc2_resume(struct device *dev)
2033 {
2034 	struct stm32_fmc2_nfc *fmc2 = dev_get_drvdata(dev);
2035 	struct stm32_fmc2_nand *nand = &fmc2->nand;
2036 	int chip_cs, ret;
2037 
2038 	pinctrl_pm_select_default_state(dev);
2039 
2040 	ret = clk_prepare_enable(fmc2->clk);
2041 	if (ret) {
2042 		dev_err(dev, "can not enable the clock\n");
2043 		return ret;
2044 	}
2045 
2046 	stm32_fmc2_init(fmc2);
2047 
2048 	for (chip_cs = 0; chip_cs < FMC2_MAX_CE; chip_cs++) {
2049 		if (!(fmc2->cs_assigned & BIT(chip_cs)))
2050 			continue;
2051 
2052 		nand_reset(&nand->chip, chip_cs);
2053 	}
2054 
2055 	return 0;
2056 }
2057 
2058 static SIMPLE_DEV_PM_OPS(stm32_fmc2_pm_ops, stm32_fmc2_suspend,
2059 			 stm32_fmc2_resume);
2060 
2061 static const struct of_device_id stm32_fmc2_match[] = {
2062 	{.compatible = "st,stm32mp15-fmc2"},
2063 	{}
2064 };
2065 MODULE_DEVICE_TABLE(of, stm32_fmc2_match);
2066 
2067 static struct platform_driver stm32_fmc2_driver = {
2068 	.probe	= stm32_fmc2_probe,
2069 	.remove	= stm32_fmc2_remove,
2070 	.driver	= {
2071 		.name = "stm32_fmc2_nand",
2072 		.of_match_table = stm32_fmc2_match,
2073 		.pm = &stm32_fmc2_pm_ops,
2074 	},
2075 };
2076 module_platform_driver(stm32_fmc2_driver);
2077 
2078 MODULE_ALIAS("platform:stm32_fmc2_nand");
2079 MODULE_AUTHOR("Christophe Kerello <christophe.kerello@st.com>");
2080 MODULE_DESCRIPTION("STMicroelectronics STM32 FMC2 nand driver");
2081 MODULE_LICENSE("GPL v2");
2082