xref: /openbmc/linux/drivers/mtd/nand/raw/tegra_nand.c (revision 83146efc)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2018 Stefan Agner <stefan@agner.ch>
4  * Copyright (C) 2014-2015 Lucas Stach <dev@lynxeye.de>
5  * Copyright (C) 2012 Avionic Design GmbH
6  */
7 
8 #include <linux/clk.h>
9 #include <linux/completion.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/err.h>
12 #include <linux/gpio/consumer.h>
13 #include <linux/interrupt.h>
14 #include <linux/io.h>
15 #include <linux/module.h>
16 #include <linux/mtd/partitions.h>
17 #include <linux/mtd/rawnand.h>
18 #include <linux/of.h>
19 #include <linux/platform_device.h>
20 #include <linux/pm_runtime.h>
21 #include <linux/reset.h>
22 
23 #include <soc/tegra/common.h>
24 
25 #define COMMAND					0x00
26 #define   COMMAND_GO				BIT(31)
27 #define   COMMAND_CLE				BIT(30)
28 #define   COMMAND_ALE				BIT(29)
29 #define   COMMAND_PIO				BIT(28)
30 #define   COMMAND_TX				BIT(27)
31 #define   COMMAND_RX				BIT(26)
32 #define   COMMAND_SEC_CMD			BIT(25)
33 #define   COMMAND_AFT_DAT			BIT(24)
34 #define   COMMAND_TRANS_SIZE(size)		((((size) - 1) & 0xf) << 20)
35 #define   COMMAND_A_VALID			BIT(19)
36 #define   COMMAND_B_VALID			BIT(18)
37 #define   COMMAND_RD_STATUS_CHK			BIT(17)
38 #define   COMMAND_RBSY_CHK			BIT(16)
39 #define   COMMAND_CE(x)				BIT(8 + ((x) & 0x7))
40 #define   COMMAND_CLE_SIZE(size)		((((size) - 1) & 0x3) << 4)
41 #define   COMMAND_ALE_SIZE(size)		((((size) - 1) & 0xf) << 0)
42 
43 #define STATUS					0x04
44 
45 #define ISR					0x08
46 #define   ISR_CORRFAIL_ERR			BIT(24)
47 #define   ISR_UND				BIT(7)
48 #define   ISR_OVR				BIT(6)
49 #define   ISR_CMD_DONE				BIT(5)
50 #define   ISR_ECC_ERR				BIT(4)
51 
52 #define IER					0x0c
53 #define   IER_ERR_TRIG_VAL(x)			(((x) & 0xf) << 16)
54 #define   IER_UND				BIT(7)
55 #define   IER_OVR				BIT(6)
56 #define   IER_CMD_DONE				BIT(5)
57 #define   IER_ECC_ERR				BIT(4)
58 #define   IER_GIE				BIT(0)
59 
60 #define CONFIG					0x10
61 #define   CONFIG_HW_ECC				BIT(31)
62 #define   CONFIG_ECC_SEL			BIT(30)
63 #define   CONFIG_ERR_COR			BIT(29)
64 #define   CONFIG_PIPE_EN			BIT(28)
65 #define   CONFIG_TVAL_4				(0 << 24)
66 #define   CONFIG_TVAL_6				(1 << 24)
67 #define   CONFIG_TVAL_8				(2 << 24)
68 #define   CONFIG_SKIP_SPARE			BIT(23)
69 #define   CONFIG_BUS_WIDTH_16			BIT(21)
70 #define   CONFIG_COM_BSY			BIT(20)
71 #define   CONFIG_PS_256				(0 << 16)
72 #define   CONFIG_PS_512				(1 << 16)
73 #define   CONFIG_PS_1024			(2 << 16)
74 #define   CONFIG_PS_2048			(3 << 16)
75 #define   CONFIG_PS_4096			(4 << 16)
76 #define   CONFIG_SKIP_SPARE_SIZE_4		(0 << 14)
77 #define   CONFIG_SKIP_SPARE_SIZE_8		(1 << 14)
78 #define   CONFIG_SKIP_SPARE_SIZE_12		(2 << 14)
79 #define   CONFIG_SKIP_SPARE_SIZE_16		(3 << 14)
80 #define   CONFIG_TAG_BYTE_SIZE(x)			((x) & 0xff)
81 
82 #define TIMING_1				0x14
83 #define   TIMING_TRP_RESP(x)			(((x) & 0xf) << 28)
84 #define   TIMING_TWB(x)				(((x) & 0xf) << 24)
85 #define   TIMING_TCR_TAR_TRR(x)			(((x) & 0xf) << 20)
86 #define   TIMING_TWHR(x)			(((x) & 0xf) << 16)
87 #define   TIMING_TCS(x)				(((x) & 0x3) << 14)
88 #define   TIMING_TWH(x)				(((x) & 0x3) << 12)
89 #define   TIMING_TWP(x)				(((x) & 0xf) <<  8)
90 #define   TIMING_TRH(x)				(((x) & 0x3) <<  4)
91 #define   TIMING_TRP(x)				(((x) & 0xf) <<  0)
92 
93 #define RESP					0x18
94 
95 #define TIMING_2				0x1c
96 #define   TIMING_TADL(x)			((x) & 0xf)
97 
98 #define CMD_REG1				0x20
99 #define CMD_REG2				0x24
100 #define ADDR_REG1				0x28
101 #define ADDR_REG2				0x2c
102 
103 #define DMA_MST_CTRL				0x30
104 #define   DMA_MST_CTRL_GO			BIT(31)
105 #define   DMA_MST_CTRL_IN			(0 << 30)
106 #define   DMA_MST_CTRL_OUT			BIT(30)
107 #define   DMA_MST_CTRL_PERF_EN			BIT(29)
108 #define   DMA_MST_CTRL_IE_DONE			BIT(28)
109 #define   DMA_MST_CTRL_REUSE			BIT(27)
110 #define   DMA_MST_CTRL_BURST_1			(2 << 24)
111 #define   DMA_MST_CTRL_BURST_4			(3 << 24)
112 #define   DMA_MST_CTRL_BURST_8			(4 << 24)
113 #define   DMA_MST_CTRL_BURST_16			(5 << 24)
114 #define   DMA_MST_CTRL_IS_DONE			BIT(20)
115 #define   DMA_MST_CTRL_EN_A			BIT(2)
116 #define   DMA_MST_CTRL_EN_B			BIT(1)
117 
118 #define DMA_CFG_A				0x34
119 #define DMA_CFG_B				0x38
120 
121 #define FIFO_CTRL				0x3c
122 #define   FIFO_CTRL_CLR_ALL			BIT(3)
123 
124 #define DATA_PTR				0x40
125 #define TAG_PTR					0x44
126 #define ECC_PTR					0x48
127 
128 #define DEC_STATUS				0x4c
129 #define   DEC_STATUS_A_ECC_FAIL			BIT(1)
130 #define   DEC_STATUS_ERR_COUNT_MASK		0x00ff0000
131 #define   DEC_STATUS_ERR_COUNT_SHIFT		16
132 
133 #define HWSTATUS_CMD				0x50
134 #define HWSTATUS_MASK				0x54
135 #define   HWSTATUS_RDSTATUS_MASK(x)		(((x) & 0xff) << 24)
136 #define   HWSTATUS_RDSTATUS_VALUE(x)		(((x) & 0xff) << 16)
137 #define   HWSTATUS_RBSY_MASK(x)			(((x) & 0xff) << 8)
138 #define   HWSTATUS_RBSY_VALUE(x)		(((x) & 0xff) << 0)
139 
140 #define BCH_CONFIG				0xcc
141 #define   BCH_ENABLE				BIT(0)
142 #define   BCH_TVAL_4				(0 << 4)
143 #define   BCH_TVAL_8				(1 << 4)
144 #define   BCH_TVAL_14				(2 << 4)
145 #define   BCH_TVAL_16				(3 << 4)
146 
147 #define DEC_STAT_RESULT				0xd0
148 #define DEC_STAT_BUF				0xd4
149 #define   DEC_STAT_BUF_FAIL_SEC_FLAG_MASK	0xff000000
150 #define   DEC_STAT_BUF_FAIL_SEC_FLAG_SHIFT	24
151 #define   DEC_STAT_BUF_CORR_SEC_FLAG_MASK	0x00ff0000
152 #define   DEC_STAT_BUF_CORR_SEC_FLAG_SHIFT	16
153 #define   DEC_STAT_BUF_MAX_CORR_CNT_MASK	0x00001f00
154 #define   DEC_STAT_BUF_MAX_CORR_CNT_SHIFT	8
155 
156 #define OFFSET(val, off)	((val) < (off) ? 0 : (val) - (off))
157 
158 #define SKIP_SPARE_BYTES	4
159 #define BITS_PER_STEP_RS	18
160 #define BITS_PER_STEP_BCH	13
161 
162 #define INT_MASK		(IER_UND | IER_OVR | IER_CMD_DONE | IER_GIE)
163 #define HWSTATUS_CMD_DEFAULT	NAND_STATUS_READY
164 #define HWSTATUS_MASK_DEFAULT	(HWSTATUS_RDSTATUS_MASK(1) | \
165 				HWSTATUS_RDSTATUS_VALUE(0) | \
166 				HWSTATUS_RBSY_MASK(NAND_STATUS_READY) | \
167 				HWSTATUS_RBSY_VALUE(NAND_STATUS_READY))
168 
169 struct tegra_nand_controller {
170 	struct nand_controller controller;
171 	struct device *dev;
172 	void __iomem *regs;
173 	int irq;
174 	struct clk *clk;
175 	struct completion command_complete;
176 	struct completion dma_complete;
177 	bool last_read_error;
178 	int cur_cs;
179 	struct nand_chip *chip;
180 };
181 
182 struct tegra_nand_chip {
183 	struct nand_chip chip;
184 	struct gpio_desc *wp_gpio;
185 	struct mtd_oob_region ecc;
186 	u32 config;
187 	u32 config_ecc;
188 	u32 bch_config;
189 	int cs[1];
190 };
191 
192 static inline struct tegra_nand_controller *
193 			to_tegra_ctrl(struct nand_controller *hw_ctrl)
194 {
195 	return container_of(hw_ctrl, struct tegra_nand_controller, controller);
196 }
197 
198 static inline struct tegra_nand_chip *to_tegra_chip(struct nand_chip *chip)
199 {
200 	return container_of(chip, struct tegra_nand_chip, chip);
201 }
202 
203 static int tegra_nand_ooblayout_rs_ecc(struct mtd_info *mtd, int section,
204 				       struct mtd_oob_region *oobregion)
205 {
206 	struct nand_chip *chip = mtd_to_nand(mtd);
207 	int bytes_per_step = DIV_ROUND_UP(BITS_PER_STEP_RS * chip->ecc.strength,
208 					  BITS_PER_BYTE);
209 
210 	if (section > 0)
211 		return -ERANGE;
212 
213 	oobregion->offset = SKIP_SPARE_BYTES;
214 	oobregion->length = round_up(bytes_per_step * chip->ecc.steps, 4);
215 
216 	return 0;
217 }
218 
219 static int tegra_nand_ooblayout_no_free(struct mtd_info *mtd, int section,
220 					struct mtd_oob_region *oobregion)
221 {
222 	return -ERANGE;
223 }
224 
225 static const struct mtd_ooblayout_ops tegra_nand_oob_rs_ops = {
226 	.ecc = tegra_nand_ooblayout_rs_ecc,
227 	.free = tegra_nand_ooblayout_no_free,
228 };
229 
230 static int tegra_nand_ooblayout_bch_ecc(struct mtd_info *mtd, int section,
231 					struct mtd_oob_region *oobregion)
232 {
233 	struct nand_chip *chip = mtd_to_nand(mtd);
234 	int bytes_per_step = DIV_ROUND_UP(BITS_PER_STEP_BCH * chip->ecc.strength,
235 					  BITS_PER_BYTE);
236 
237 	if (section > 0)
238 		return -ERANGE;
239 
240 	oobregion->offset = SKIP_SPARE_BYTES;
241 	oobregion->length = round_up(bytes_per_step * chip->ecc.steps, 4);
242 
243 	return 0;
244 }
245 
246 static const struct mtd_ooblayout_ops tegra_nand_oob_bch_ops = {
247 	.ecc = tegra_nand_ooblayout_bch_ecc,
248 	.free = tegra_nand_ooblayout_no_free,
249 };
250 
251 static irqreturn_t tegra_nand_irq(int irq, void *data)
252 {
253 	struct tegra_nand_controller *ctrl = data;
254 	u32 isr, dma;
255 
256 	isr = readl_relaxed(ctrl->regs + ISR);
257 	dma = readl_relaxed(ctrl->regs + DMA_MST_CTRL);
258 	dev_dbg(ctrl->dev, "isr %08x\n", isr);
259 
260 	if (!isr && !(dma & DMA_MST_CTRL_IS_DONE))
261 		return IRQ_NONE;
262 
263 	/*
264 	 * The bit name is somewhat missleading: This is also set when
265 	 * HW ECC was successful. The data sheet states:
266 	 * Correctable OR Un-correctable errors occurred in the DMA transfer...
267 	 */
268 	if (isr & ISR_CORRFAIL_ERR)
269 		ctrl->last_read_error = true;
270 
271 	if (isr & ISR_CMD_DONE)
272 		complete(&ctrl->command_complete);
273 
274 	if (isr & ISR_UND)
275 		dev_err(ctrl->dev, "FIFO underrun\n");
276 
277 	if (isr & ISR_OVR)
278 		dev_err(ctrl->dev, "FIFO overrun\n");
279 
280 	/* handle DMA interrupts */
281 	if (dma & DMA_MST_CTRL_IS_DONE) {
282 		writel_relaxed(dma, ctrl->regs + DMA_MST_CTRL);
283 		complete(&ctrl->dma_complete);
284 	}
285 
286 	/* clear interrupts */
287 	writel_relaxed(isr, ctrl->regs + ISR);
288 
289 	return IRQ_HANDLED;
290 }
291 
292 static const char * const tegra_nand_reg_names[] = {
293 	"COMMAND",
294 	"STATUS",
295 	"ISR",
296 	"IER",
297 	"CONFIG",
298 	"TIMING",
299 	NULL,
300 	"TIMING2",
301 	"CMD_REG1",
302 	"CMD_REG2",
303 	"ADDR_REG1",
304 	"ADDR_REG2",
305 	"DMA_MST_CTRL",
306 	"DMA_CFG_A",
307 	"DMA_CFG_B",
308 	"FIFO_CTRL",
309 };
310 
311 static void tegra_nand_dump_reg(struct tegra_nand_controller *ctrl)
312 {
313 	u32 reg;
314 	int i;
315 
316 	dev_err(ctrl->dev, "Tegra NAND controller register dump\n");
317 	for (i = 0; i < ARRAY_SIZE(tegra_nand_reg_names); i++) {
318 		const char *reg_name = tegra_nand_reg_names[i];
319 
320 		if (!reg_name)
321 			continue;
322 
323 		reg = readl_relaxed(ctrl->regs + (i * 4));
324 		dev_err(ctrl->dev, "%s: 0x%08x\n", reg_name, reg);
325 	}
326 }
327 
328 static void tegra_nand_controller_abort(struct tegra_nand_controller *ctrl)
329 {
330 	u32 isr, dma;
331 
332 	disable_irq(ctrl->irq);
333 
334 	/* Abort current command/DMA operation */
335 	writel_relaxed(0, ctrl->regs + DMA_MST_CTRL);
336 	writel_relaxed(0, ctrl->regs + COMMAND);
337 
338 	/* clear interrupts */
339 	isr = readl_relaxed(ctrl->regs + ISR);
340 	writel_relaxed(isr, ctrl->regs + ISR);
341 	dma = readl_relaxed(ctrl->regs + DMA_MST_CTRL);
342 	writel_relaxed(dma, ctrl->regs + DMA_MST_CTRL);
343 
344 	reinit_completion(&ctrl->command_complete);
345 	reinit_completion(&ctrl->dma_complete);
346 
347 	enable_irq(ctrl->irq);
348 }
349 
350 static int tegra_nand_cmd(struct nand_chip *chip,
351 			  const struct nand_subop *subop)
352 {
353 	const struct nand_op_instr *instr;
354 	const struct nand_op_instr *instr_data_in = NULL;
355 	struct tegra_nand_controller *ctrl = to_tegra_ctrl(chip->controller);
356 	unsigned int op_id, size = 0, offset = 0;
357 	bool first_cmd = true;
358 	u32 reg, cmd = 0;
359 	int ret;
360 
361 	for (op_id = 0; op_id < subop->ninstrs; op_id++) {
362 		unsigned int naddrs, i;
363 		const u8 *addrs;
364 		u32 addr1 = 0, addr2 = 0;
365 
366 		instr = &subop->instrs[op_id];
367 
368 		switch (instr->type) {
369 		case NAND_OP_CMD_INSTR:
370 			if (first_cmd) {
371 				cmd |= COMMAND_CLE;
372 				writel_relaxed(instr->ctx.cmd.opcode,
373 					       ctrl->regs + CMD_REG1);
374 			} else {
375 				cmd |= COMMAND_SEC_CMD;
376 				writel_relaxed(instr->ctx.cmd.opcode,
377 					       ctrl->regs + CMD_REG2);
378 			}
379 			first_cmd = false;
380 			break;
381 
382 		case NAND_OP_ADDR_INSTR:
383 			offset = nand_subop_get_addr_start_off(subop, op_id);
384 			naddrs = nand_subop_get_num_addr_cyc(subop, op_id);
385 			addrs = &instr->ctx.addr.addrs[offset];
386 
387 			cmd |= COMMAND_ALE | COMMAND_ALE_SIZE(naddrs);
388 			for (i = 0; i < min_t(unsigned int, 4, naddrs); i++)
389 				addr1 |= *addrs++ << (BITS_PER_BYTE * i);
390 			naddrs -= i;
391 			for (i = 0; i < min_t(unsigned int, 4, naddrs); i++)
392 				addr2 |= *addrs++ << (BITS_PER_BYTE * i);
393 
394 			writel_relaxed(addr1, ctrl->regs + ADDR_REG1);
395 			writel_relaxed(addr2, ctrl->regs + ADDR_REG2);
396 			break;
397 
398 		case NAND_OP_DATA_IN_INSTR:
399 			size = nand_subop_get_data_len(subop, op_id);
400 			offset = nand_subop_get_data_start_off(subop, op_id);
401 
402 			cmd |= COMMAND_TRANS_SIZE(size) | COMMAND_PIO |
403 				COMMAND_RX | COMMAND_A_VALID;
404 
405 			instr_data_in = instr;
406 			break;
407 
408 		case NAND_OP_DATA_OUT_INSTR:
409 			size = nand_subop_get_data_len(subop, op_id);
410 			offset = nand_subop_get_data_start_off(subop, op_id);
411 
412 			cmd |= COMMAND_TRANS_SIZE(size) | COMMAND_PIO |
413 				COMMAND_TX | COMMAND_A_VALID;
414 			memcpy(&reg, instr->ctx.data.buf.out + offset, size);
415 
416 			writel_relaxed(reg, ctrl->regs + RESP);
417 			break;
418 
419 		case NAND_OP_WAITRDY_INSTR:
420 			cmd |= COMMAND_RBSY_CHK;
421 			break;
422 		}
423 	}
424 
425 	cmd |= COMMAND_GO | COMMAND_CE(ctrl->cur_cs);
426 	writel_relaxed(cmd, ctrl->regs + COMMAND);
427 	ret = wait_for_completion_timeout(&ctrl->command_complete,
428 					  msecs_to_jiffies(500));
429 	if (!ret) {
430 		dev_err(ctrl->dev, "COMMAND timeout\n");
431 		tegra_nand_dump_reg(ctrl);
432 		tegra_nand_controller_abort(ctrl);
433 		return -ETIMEDOUT;
434 	}
435 
436 	if (instr_data_in) {
437 		reg = readl_relaxed(ctrl->regs + RESP);
438 		memcpy(instr_data_in->ctx.data.buf.in + offset, &reg, size);
439 	}
440 
441 	return 0;
442 }
443 
444 static const struct nand_op_parser tegra_nand_op_parser = NAND_OP_PARSER(
445 	NAND_OP_PARSER_PATTERN(tegra_nand_cmd,
446 		NAND_OP_PARSER_PAT_CMD_ELEM(true),
447 		NAND_OP_PARSER_PAT_ADDR_ELEM(true, 8),
448 		NAND_OP_PARSER_PAT_CMD_ELEM(true),
449 		NAND_OP_PARSER_PAT_WAITRDY_ELEM(true)),
450 	NAND_OP_PARSER_PATTERN(tegra_nand_cmd,
451 		NAND_OP_PARSER_PAT_DATA_OUT_ELEM(false, 4)),
452 	NAND_OP_PARSER_PATTERN(tegra_nand_cmd,
453 		NAND_OP_PARSER_PAT_CMD_ELEM(true),
454 		NAND_OP_PARSER_PAT_ADDR_ELEM(true, 8),
455 		NAND_OP_PARSER_PAT_CMD_ELEM(true),
456 		NAND_OP_PARSER_PAT_WAITRDY_ELEM(true),
457 		NAND_OP_PARSER_PAT_DATA_IN_ELEM(true, 4)),
458 	);
459 
460 static void tegra_nand_select_target(struct nand_chip *chip,
461 				     unsigned int die_nr)
462 {
463 	struct tegra_nand_chip *nand = to_tegra_chip(chip);
464 	struct tegra_nand_controller *ctrl = to_tegra_ctrl(chip->controller);
465 
466 	ctrl->cur_cs = nand->cs[die_nr];
467 }
468 
469 static int tegra_nand_exec_op(struct nand_chip *chip,
470 			      const struct nand_operation *op,
471 			      bool check_only)
472 {
473 	if (!check_only)
474 		tegra_nand_select_target(chip, op->cs);
475 
476 	return nand_op_parser_exec_op(chip, &tegra_nand_op_parser, op,
477 				      check_only);
478 }
479 
480 static void tegra_nand_hw_ecc(struct tegra_nand_controller *ctrl,
481 			      struct nand_chip *chip, bool enable)
482 {
483 	struct tegra_nand_chip *nand = to_tegra_chip(chip);
484 
485 	if (chip->ecc.algo == NAND_ECC_ALGO_BCH && enable)
486 		writel_relaxed(nand->bch_config, ctrl->regs + BCH_CONFIG);
487 	else
488 		writel_relaxed(0, ctrl->regs + BCH_CONFIG);
489 
490 	if (enable)
491 		writel_relaxed(nand->config_ecc, ctrl->regs + CONFIG);
492 	else
493 		writel_relaxed(nand->config, ctrl->regs + CONFIG);
494 }
495 
496 static int tegra_nand_page_xfer(struct mtd_info *mtd, struct nand_chip *chip,
497 				void *buf, void *oob_buf, int oob_len, int page,
498 				bool read)
499 {
500 	struct tegra_nand_controller *ctrl = to_tegra_ctrl(chip->controller);
501 	enum dma_data_direction dir = read ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
502 	dma_addr_t dma_addr = 0, dma_addr_oob = 0;
503 	u32 addr1, cmd, dma_ctrl;
504 	int ret;
505 
506 	tegra_nand_select_target(chip, chip->cur_cs);
507 
508 	if (read) {
509 		writel_relaxed(NAND_CMD_READ0, ctrl->regs + CMD_REG1);
510 		writel_relaxed(NAND_CMD_READSTART, ctrl->regs + CMD_REG2);
511 	} else {
512 		writel_relaxed(NAND_CMD_SEQIN, ctrl->regs + CMD_REG1);
513 		writel_relaxed(NAND_CMD_PAGEPROG, ctrl->regs + CMD_REG2);
514 	}
515 	cmd = COMMAND_CLE | COMMAND_SEC_CMD;
516 
517 	/* Lower 16-bits are column, by default 0 */
518 	addr1 = page << 16;
519 
520 	if (!buf)
521 		addr1 |= mtd->writesize;
522 	writel_relaxed(addr1, ctrl->regs + ADDR_REG1);
523 
524 	if (chip->options & NAND_ROW_ADDR_3) {
525 		writel_relaxed(page >> 16, ctrl->regs + ADDR_REG2);
526 		cmd |= COMMAND_ALE | COMMAND_ALE_SIZE(5);
527 	} else {
528 		cmd |= COMMAND_ALE | COMMAND_ALE_SIZE(4);
529 	}
530 
531 	if (buf) {
532 		dma_addr = dma_map_single(ctrl->dev, buf, mtd->writesize, dir);
533 		ret = dma_mapping_error(ctrl->dev, dma_addr);
534 		if (ret) {
535 			dev_err(ctrl->dev, "dma mapping error\n");
536 			return -EINVAL;
537 		}
538 
539 		writel_relaxed(mtd->writesize - 1, ctrl->regs + DMA_CFG_A);
540 		writel_relaxed(dma_addr, ctrl->regs + DATA_PTR);
541 	}
542 
543 	if (oob_buf) {
544 		dma_addr_oob = dma_map_single(ctrl->dev, oob_buf, mtd->oobsize,
545 					      dir);
546 		ret = dma_mapping_error(ctrl->dev, dma_addr_oob);
547 		if (ret) {
548 			dev_err(ctrl->dev, "dma mapping error\n");
549 			ret = -EINVAL;
550 			goto err_unmap_dma_page;
551 		}
552 
553 		writel_relaxed(oob_len - 1, ctrl->regs + DMA_CFG_B);
554 		writel_relaxed(dma_addr_oob, ctrl->regs + TAG_PTR);
555 	}
556 
557 	dma_ctrl = DMA_MST_CTRL_GO | DMA_MST_CTRL_PERF_EN |
558 		   DMA_MST_CTRL_IE_DONE | DMA_MST_CTRL_IS_DONE |
559 		   DMA_MST_CTRL_BURST_16;
560 
561 	if (buf)
562 		dma_ctrl |= DMA_MST_CTRL_EN_A;
563 	if (oob_buf)
564 		dma_ctrl |= DMA_MST_CTRL_EN_B;
565 
566 	if (read)
567 		dma_ctrl |= DMA_MST_CTRL_IN | DMA_MST_CTRL_REUSE;
568 	else
569 		dma_ctrl |= DMA_MST_CTRL_OUT;
570 
571 	writel_relaxed(dma_ctrl, ctrl->regs + DMA_MST_CTRL);
572 
573 	cmd |= COMMAND_GO | COMMAND_RBSY_CHK | COMMAND_TRANS_SIZE(9) |
574 	       COMMAND_CE(ctrl->cur_cs);
575 
576 	if (buf)
577 		cmd |= COMMAND_A_VALID;
578 	if (oob_buf)
579 		cmd |= COMMAND_B_VALID;
580 
581 	if (read)
582 		cmd |= COMMAND_RX;
583 	else
584 		cmd |= COMMAND_TX | COMMAND_AFT_DAT;
585 
586 	writel_relaxed(cmd, ctrl->regs + COMMAND);
587 
588 	ret = wait_for_completion_timeout(&ctrl->command_complete,
589 					  msecs_to_jiffies(500));
590 	if (!ret) {
591 		dev_err(ctrl->dev, "COMMAND timeout\n");
592 		tegra_nand_dump_reg(ctrl);
593 		tegra_nand_controller_abort(ctrl);
594 		ret = -ETIMEDOUT;
595 		goto err_unmap_dma;
596 	}
597 
598 	ret = wait_for_completion_timeout(&ctrl->dma_complete,
599 					  msecs_to_jiffies(500));
600 	if (!ret) {
601 		dev_err(ctrl->dev, "DMA timeout\n");
602 		tegra_nand_dump_reg(ctrl);
603 		tegra_nand_controller_abort(ctrl);
604 		ret = -ETIMEDOUT;
605 		goto err_unmap_dma;
606 	}
607 	ret = 0;
608 
609 err_unmap_dma:
610 	if (oob_buf)
611 		dma_unmap_single(ctrl->dev, dma_addr_oob, mtd->oobsize, dir);
612 err_unmap_dma_page:
613 	if (buf)
614 		dma_unmap_single(ctrl->dev, dma_addr, mtd->writesize, dir);
615 
616 	return ret;
617 }
618 
619 static int tegra_nand_read_page_raw(struct nand_chip *chip, u8 *buf,
620 				    int oob_required, int page)
621 {
622 	struct mtd_info *mtd = nand_to_mtd(chip);
623 	void *oob_buf = oob_required ? chip->oob_poi : NULL;
624 
625 	return tegra_nand_page_xfer(mtd, chip, buf, oob_buf,
626 				    mtd->oobsize, page, true);
627 }
628 
629 static int tegra_nand_write_page_raw(struct nand_chip *chip, const u8 *buf,
630 				     int oob_required, int page)
631 {
632 	struct mtd_info *mtd = nand_to_mtd(chip);
633 	void *oob_buf = oob_required ? chip->oob_poi : NULL;
634 
635 	return tegra_nand_page_xfer(mtd, chip, (void *)buf, oob_buf,
636 				     mtd->oobsize, page, false);
637 }
638 
639 static int tegra_nand_read_oob(struct nand_chip *chip, int page)
640 {
641 	struct mtd_info *mtd = nand_to_mtd(chip);
642 
643 	return tegra_nand_page_xfer(mtd, chip, NULL, chip->oob_poi,
644 				    mtd->oobsize, page, true);
645 }
646 
647 static int tegra_nand_write_oob(struct nand_chip *chip, int page)
648 {
649 	struct mtd_info *mtd = nand_to_mtd(chip);
650 
651 	return tegra_nand_page_xfer(mtd, chip, NULL, chip->oob_poi,
652 				    mtd->oobsize, page, false);
653 }
654 
655 static int tegra_nand_read_page_hwecc(struct nand_chip *chip, u8 *buf,
656 				      int oob_required, int page)
657 {
658 	struct mtd_info *mtd = nand_to_mtd(chip);
659 	struct tegra_nand_controller *ctrl = to_tegra_ctrl(chip->controller);
660 	struct tegra_nand_chip *nand = to_tegra_chip(chip);
661 	void *oob_buf = oob_required ? chip->oob_poi : NULL;
662 	u32 dec_stat, max_corr_cnt;
663 	unsigned long fail_sec_flag;
664 	int ret;
665 
666 	tegra_nand_hw_ecc(ctrl, chip, true);
667 	ret = tegra_nand_page_xfer(mtd, chip, buf, oob_buf, 0, page, true);
668 	tegra_nand_hw_ecc(ctrl, chip, false);
669 	if (ret)
670 		return ret;
671 
672 	/* No correctable or un-correctable errors, page must have 0 bitflips */
673 	if (!ctrl->last_read_error)
674 		return 0;
675 
676 	/*
677 	 * Correctable or un-correctable errors occurred. Use DEC_STAT_BUF
678 	 * which contains information for all ECC selections.
679 	 *
680 	 * Note that since we do not use Command Queues DEC_RESULT does not
681 	 * state the number of pages we can read from the DEC_STAT_BUF. But
682 	 * since CORRFAIL_ERR did occur during page read we do have a valid
683 	 * result in DEC_STAT_BUF.
684 	 */
685 	ctrl->last_read_error = false;
686 	dec_stat = readl_relaxed(ctrl->regs + DEC_STAT_BUF);
687 
688 	fail_sec_flag = (dec_stat & DEC_STAT_BUF_FAIL_SEC_FLAG_MASK) >>
689 			DEC_STAT_BUF_FAIL_SEC_FLAG_SHIFT;
690 
691 	max_corr_cnt = (dec_stat & DEC_STAT_BUF_MAX_CORR_CNT_MASK) >>
692 		       DEC_STAT_BUF_MAX_CORR_CNT_SHIFT;
693 
694 	if (fail_sec_flag) {
695 		int bit, max_bitflips = 0;
696 
697 		/*
698 		 * Since we do not support subpage writes, a complete page
699 		 * is either written or not. We can take a shortcut here by
700 		 * checking wheather any of the sector has been successful
701 		 * read. If at least one sectors has been read successfully,
702 		 * the page must have been a written previously. It cannot
703 		 * be an erased page.
704 		 *
705 		 * E.g. controller might return fail_sec_flag with 0x4, which
706 		 * would mean only the third sector failed to correct. The
707 		 * page must have been written and the third sector is really
708 		 * not correctable anymore.
709 		 */
710 		if (fail_sec_flag ^ GENMASK(chip->ecc.steps - 1, 0)) {
711 			mtd->ecc_stats.failed += hweight8(fail_sec_flag);
712 			return max_corr_cnt;
713 		}
714 
715 		/*
716 		 * All sectors failed to correct, but the ECC isn't smart
717 		 * enough to figure out if a page is really just erased.
718 		 * Read OOB data and check whether data/OOB is completely
719 		 * erased or if error correction just failed for all sub-
720 		 * pages.
721 		 */
722 		ret = tegra_nand_read_oob(chip, page);
723 		if (ret < 0)
724 			return ret;
725 
726 		for_each_set_bit(bit, &fail_sec_flag, chip->ecc.steps) {
727 			u8 *data = buf + (chip->ecc.size * bit);
728 			u8 *oob = chip->oob_poi + nand->ecc.offset +
729 				  (chip->ecc.bytes * bit);
730 
731 			ret = nand_check_erased_ecc_chunk(data, chip->ecc.size,
732 							  oob, chip->ecc.bytes,
733 							  NULL, 0,
734 							  chip->ecc.strength);
735 			if (ret < 0) {
736 				mtd->ecc_stats.failed++;
737 			} else {
738 				mtd->ecc_stats.corrected += ret;
739 				max_bitflips = max(ret, max_bitflips);
740 			}
741 		}
742 
743 		return max_t(unsigned int, max_corr_cnt, max_bitflips);
744 	} else {
745 		int corr_sec_flag;
746 
747 		corr_sec_flag = (dec_stat & DEC_STAT_BUF_CORR_SEC_FLAG_MASK) >>
748 				DEC_STAT_BUF_CORR_SEC_FLAG_SHIFT;
749 
750 		/*
751 		 * The value returned in the register is the maximum of
752 		 * bitflips encountered in any of the ECC regions. As there is
753 		 * no way to get the number of bitflips in a specific regions
754 		 * we are not able to deliver correct stats but instead
755 		 * overestimate the number of corrected bitflips by assuming
756 		 * that all regions where errors have been corrected
757 		 * encountered the maximum number of bitflips.
758 		 */
759 		mtd->ecc_stats.corrected += max_corr_cnt * hweight8(corr_sec_flag);
760 
761 		return max_corr_cnt;
762 	}
763 }
764 
765 static int tegra_nand_write_page_hwecc(struct nand_chip *chip, const u8 *buf,
766 				       int oob_required, int page)
767 {
768 	struct mtd_info *mtd = nand_to_mtd(chip);
769 	struct tegra_nand_controller *ctrl = to_tegra_ctrl(chip->controller);
770 	void *oob_buf = oob_required ? chip->oob_poi : NULL;
771 	int ret;
772 
773 	tegra_nand_hw_ecc(ctrl, chip, true);
774 	ret = tegra_nand_page_xfer(mtd, chip, (void *)buf, oob_buf,
775 				   0, page, false);
776 	tegra_nand_hw_ecc(ctrl, chip, false);
777 
778 	return ret;
779 }
780 
781 static void tegra_nand_setup_timing(struct tegra_nand_controller *ctrl,
782 				    const struct nand_sdr_timings *timings)
783 {
784 	/*
785 	 * The period (and all other timings in this function) is in ps,
786 	 * so need to take care here to avoid integer overflows.
787 	 */
788 	unsigned int rate = clk_get_rate(ctrl->clk) / 1000000;
789 	unsigned int period = DIV_ROUND_UP(1000000, rate);
790 	u32 val, reg = 0;
791 
792 	val = DIV_ROUND_UP(max3(timings->tAR_min, timings->tRR_min,
793 				timings->tRC_min), period);
794 	reg |= TIMING_TCR_TAR_TRR(OFFSET(val, 3));
795 
796 	val = DIV_ROUND_UP(max(max(timings->tCS_min, timings->tCH_min),
797 			       max(timings->tALS_min, timings->tALH_min)),
798 			   period);
799 	reg |= TIMING_TCS(OFFSET(val, 2));
800 
801 	val = DIV_ROUND_UP(max(timings->tRP_min, timings->tREA_max) + 6000,
802 			   period);
803 	reg |= TIMING_TRP(OFFSET(val, 1)) | TIMING_TRP_RESP(OFFSET(val, 1));
804 
805 	reg |= TIMING_TWB(OFFSET(DIV_ROUND_UP(timings->tWB_max, period), 1));
806 	reg |= TIMING_TWHR(OFFSET(DIV_ROUND_UP(timings->tWHR_min, period), 1));
807 	reg |= TIMING_TWH(OFFSET(DIV_ROUND_UP(timings->tWH_min, period), 1));
808 	reg |= TIMING_TWP(OFFSET(DIV_ROUND_UP(timings->tWP_min, period), 1));
809 	reg |= TIMING_TRH(OFFSET(DIV_ROUND_UP(timings->tREH_min, period), 1));
810 
811 	writel_relaxed(reg, ctrl->regs + TIMING_1);
812 
813 	val = DIV_ROUND_UP(timings->tADL_min, period);
814 	reg = TIMING_TADL(OFFSET(val, 3));
815 
816 	writel_relaxed(reg, ctrl->regs + TIMING_2);
817 }
818 
819 static int tegra_nand_setup_interface(struct nand_chip *chip, int csline,
820 				      const struct nand_interface_config *conf)
821 {
822 	struct tegra_nand_controller *ctrl = to_tegra_ctrl(chip->controller);
823 	const struct nand_sdr_timings *timings;
824 
825 	timings = nand_get_sdr_timings(conf);
826 	if (IS_ERR(timings))
827 		return PTR_ERR(timings);
828 
829 	if (csline == NAND_DATA_IFACE_CHECK_ONLY)
830 		return 0;
831 
832 	tegra_nand_setup_timing(ctrl, timings);
833 
834 	return 0;
835 }
836 
837 static const int rs_strength_bootable[] = { 4 };
838 static const int rs_strength[] = { 4, 6, 8 };
839 static const int bch_strength_bootable[] = { 8, 16 };
840 static const int bch_strength[] = { 4, 8, 14, 16 };
841 
842 static int tegra_nand_get_strength(struct nand_chip *chip, const int *strength,
843 				   int strength_len, int bits_per_step,
844 				   int oobsize)
845 {
846 	struct nand_device *base = mtd_to_nanddev(nand_to_mtd(chip));
847 	const struct nand_ecc_props *requirements =
848 		nanddev_get_ecc_requirements(base);
849 	bool maximize = base->ecc.user_conf.flags & NAND_ECC_MAXIMIZE_STRENGTH;
850 	int i;
851 
852 	/*
853 	 * Loop through available strengths. Backwards in case we try to
854 	 * maximize the BCH strength.
855 	 */
856 	for (i = 0; i < strength_len; i++) {
857 		int strength_sel, bytes_per_step, bytes_per_page;
858 
859 		if (maximize) {
860 			strength_sel = strength[strength_len - i - 1];
861 		} else {
862 			strength_sel = strength[i];
863 
864 			if (strength_sel < requirements->strength)
865 				continue;
866 		}
867 
868 		bytes_per_step = DIV_ROUND_UP(bits_per_step * strength_sel,
869 					      BITS_PER_BYTE);
870 		bytes_per_page = round_up(bytes_per_step * chip->ecc.steps, 4);
871 
872 		/* Check whether strength fits OOB */
873 		if (bytes_per_page < (oobsize - SKIP_SPARE_BYTES))
874 			return strength_sel;
875 	}
876 
877 	return -EINVAL;
878 }
879 
880 static int tegra_nand_select_strength(struct nand_chip *chip, int oobsize)
881 {
882 	const int *strength;
883 	int strength_len, bits_per_step;
884 
885 	switch (chip->ecc.algo) {
886 	case NAND_ECC_ALGO_RS:
887 		bits_per_step = BITS_PER_STEP_RS;
888 		if (chip->options & NAND_IS_BOOT_MEDIUM) {
889 			strength = rs_strength_bootable;
890 			strength_len = ARRAY_SIZE(rs_strength_bootable);
891 		} else {
892 			strength = rs_strength;
893 			strength_len = ARRAY_SIZE(rs_strength);
894 		}
895 		break;
896 	case NAND_ECC_ALGO_BCH:
897 		bits_per_step = BITS_PER_STEP_BCH;
898 		if (chip->options & NAND_IS_BOOT_MEDIUM) {
899 			strength = bch_strength_bootable;
900 			strength_len = ARRAY_SIZE(bch_strength_bootable);
901 		} else {
902 			strength = bch_strength;
903 			strength_len = ARRAY_SIZE(bch_strength);
904 		}
905 		break;
906 	default:
907 		return -EINVAL;
908 	}
909 
910 	return tegra_nand_get_strength(chip, strength, strength_len,
911 				       bits_per_step, oobsize);
912 }
913 
914 static int tegra_nand_attach_chip(struct nand_chip *chip)
915 {
916 	struct tegra_nand_controller *ctrl = to_tegra_ctrl(chip->controller);
917 	const struct nand_ecc_props *requirements =
918 		nanddev_get_ecc_requirements(&chip->base);
919 	struct tegra_nand_chip *nand = to_tegra_chip(chip);
920 	struct mtd_info *mtd = nand_to_mtd(chip);
921 	int bits_per_step;
922 	int ret;
923 
924 	if (chip->bbt_options & NAND_BBT_USE_FLASH)
925 		chip->bbt_options |= NAND_BBT_NO_OOB;
926 
927 	chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_ON_HOST;
928 	chip->ecc.size = 512;
929 	chip->ecc.steps = mtd->writesize / chip->ecc.size;
930 	if (requirements->step_size != 512) {
931 		dev_err(ctrl->dev, "Unsupported step size %d\n",
932 			requirements->step_size);
933 		return -EINVAL;
934 	}
935 
936 	chip->ecc.read_page = tegra_nand_read_page_hwecc;
937 	chip->ecc.write_page = tegra_nand_write_page_hwecc;
938 	chip->ecc.read_page_raw = tegra_nand_read_page_raw;
939 	chip->ecc.write_page_raw = tegra_nand_write_page_raw;
940 	chip->ecc.read_oob = tegra_nand_read_oob;
941 	chip->ecc.write_oob = tegra_nand_write_oob;
942 
943 	if (chip->options & NAND_BUSWIDTH_16)
944 		nand->config |= CONFIG_BUS_WIDTH_16;
945 
946 	if (chip->ecc.algo == NAND_ECC_ALGO_UNKNOWN) {
947 		if (mtd->writesize < 2048)
948 			chip->ecc.algo = NAND_ECC_ALGO_RS;
949 		else
950 			chip->ecc.algo = NAND_ECC_ALGO_BCH;
951 	}
952 
953 	if (chip->ecc.algo == NAND_ECC_ALGO_BCH && mtd->writesize < 2048) {
954 		dev_err(ctrl->dev, "BCH supports 2K or 4K page size only\n");
955 		return -EINVAL;
956 	}
957 
958 	if (!chip->ecc.strength) {
959 		ret = tegra_nand_select_strength(chip, mtd->oobsize);
960 		if (ret < 0) {
961 			dev_err(ctrl->dev,
962 				"No valid strength found, minimum %d\n",
963 				requirements->strength);
964 			return ret;
965 		}
966 
967 		chip->ecc.strength = ret;
968 	}
969 
970 	nand->config_ecc = CONFIG_PIPE_EN | CONFIG_SKIP_SPARE |
971 			   CONFIG_SKIP_SPARE_SIZE_4;
972 
973 	switch (chip->ecc.algo) {
974 	case NAND_ECC_ALGO_RS:
975 		bits_per_step = BITS_PER_STEP_RS * chip->ecc.strength;
976 		mtd_set_ooblayout(mtd, &tegra_nand_oob_rs_ops);
977 		nand->config_ecc |= CONFIG_HW_ECC | CONFIG_ECC_SEL |
978 				    CONFIG_ERR_COR;
979 		switch (chip->ecc.strength) {
980 		case 4:
981 			nand->config_ecc |= CONFIG_TVAL_4;
982 			break;
983 		case 6:
984 			nand->config_ecc |= CONFIG_TVAL_6;
985 			break;
986 		case 8:
987 			nand->config_ecc |= CONFIG_TVAL_8;
988 			break;
989 		default:
990 			dev_err(ctrl->dev, "ECC strength %d not supported\n",
991 				chip->ecc.strength);
992 			return -EINVAL;
993 		}
994 		break;
995 	case NAND_ECC_ALGO_BCH:
996 		bits_per_step = BITS_PER_STEP_BCH * chip->ecc.strength;
997 		mtd_set_ooblayout(mtd, &tegra_nand_oob_bch_ops);
998 		nand->bch_config = BCH_ENABLE;
999 		switch (chip->ecc.strength) {
1000 		case 4:
1001 			nand->bch_config |= BCH_TVAL_4;
1002 			break;
1003 		case 8:
1004 			nand->bch_config |= BCH_TVAL_8;
1005 			break;
1006 		case 14:
1007 			nand->bch_config |= BCH_TVAL_14;
1008 			break;
1009 		case 16:
1010 			nand->bch_config |= BCH_TVAL_16;
1011 			break;
1012 		default:
1013 			dev_err(ctrl->dev, "ECC strength %d not supported\n",
1014 				chip->ecc.strength);
1015 			return -EINVAL;
1016 		}
1017 		break;
1018 	default:
1019 		dev_err(ctrl->dev, "ECC algorithm not supported\n");
1020 		return -EINVAL;
1021 	}
1022 
1023 	dev_info(ctrl->dev, "Using %s with strength %d per 512 byte step\n",
1024 		 chip->ecc.algo == NAND_ECC_ALGO_BCH ? "BCH" : "RS",
1025 		 chip->ecc.strength);
1026 
1027 	chip->ecc.bytes = DIV_ROUND_UP(bits_per_step, BITS_PER_BYTE);
1028 
1029 	switch (mtd->writesize) {
1030 	case 256:
1031 		nand->config |= CONFIG_PS_256;
1032 		break;
1033 	case 512:
1034 		nand->config |= CONFIG_PS_512;
1035 		break;
1036 	case 1024:
1037 		nand->config |= CONFIG_PS_1024;
1038 		break;
1039 	case 2048:
1040 		nand->config |= CONFIG_PS_2048;
1041 		break;
1042 	case 4096:
1043 		nand->config |= CONFIG_PS_4096;
1044 		break;
1045 	default:
1046 		dev_err(ctrl->dev, "Unsupported writesize %d\n",
1047 			mtd->writesize);
1048 		return -ENODEV;
1049 	}
1050 
1051 	/* Store complete configuration for HW ECC in config_ecc */
1052 	nand->config_ecc |= nand->config;
1053 
1054 	/* Non-HW ECC read/writes complete OOB */
1055 	nand->config |= CONFIG_TAG_BYTE_SIZE(mtd->oobsize - 1);
1056 	writel_relaxed(nand->config, ctrl->regs + CONFIG);
1057 
1058 	return 0;
1059 }
1060 
1061 static const struct nand_controller_ops tegra_nand_controller_ops = {
1062 	.attach_chip = &tegra_nand_attach_chip,
1063 	.exec_op = tegra_nand_exec_op,
1064 	.setup_interface = tegra_nand_setup_interface,
1065 };
1066 
1067 static int tegra_nand_chips_init(struct device *dev,
1068 				 struct tegra_nand_controller *ctrl)
1069 {
1070 	struct device_node *np = dev->of_node;
1071 	struct device_node *np_nand;
1072 	int nsels, nchips = of_get_child_count(np);
1073 	struct tegra_nand_chip *nand;
1074 	struct mtd_info *mtd;
1075 	struct nand_chip *chip;
1076 	int ret;
1077 	u32 cs;
1078 
1079 	if (nchips != 1) {
1080 		dev_err(dev, "Currently only one NAND chip supported\n");
1081 		return -EINVAL;
1082 	}
1083 
1084 	np_nand = of_get_next_child(np, NULL);
1085 
1086 	nsels = of_property_count_elems_of_size(np_nand, "reg", sizeof(u32));
1087 	if (nsels != 1) {
1088 		dev_err(dev, "Missing/invalid reg property\n");
1089 		return -EINVAL;
1090 	}
1091 
1092 	/* Retrieve CS id, currently only single die NAND supported */
1093 	ret = of_property_read_u32(np_nand, "reg", &cs);
1094 	if (ret) {
1095 		dev_err(dev, "could not retrieve reg property: %d\n", ret);
1096 		return ret;
1097 	}
1098 
1099 	nand = devm_kzalloc(dev, sizeof(*nand), GFP_KERNEL);
1100 	if (!nand)
1101 		return -ENOMEM;
1102 
1103 	nand->cs[0] = cs;
1104 
1105 	nand->wp_gpio = devm_gpiod_get_optional(dev, "wp", GPIOD_OUT_LOW);
1106 
1107 	if (IS_ERR(nand->wp_gpio)) {
1108 		ret = PTR_ERR(nand->wp_gpio);
1109 		dev_err(dev, "Failed to request WP GPIO: %d\n", ret);
1110 		return ret;
1111 	}
1112 
1113 	chip = &nand->chip;
1114 	chip->controller = &ctrl->controller;
1115 
1116 	mtd = nand_to_mtd(chip);
1117 
1118 	mtd->dev.parent = dev;
1119 	mtd->owner = THIS_MODULE;
1120 
1121 	nand_set_flash_node(chip, np_nand);
1122 
1123 	if (!mtd->name)
1124 		mtd->name = "tegra_nand";
1125 
1126 	chip->options = NAND_NO_SUBPAGE_WRITE | NAND_USES_DMA;
1127 
1128 	ret = nand_scan(chip, 1);
1129 	if (ret)
1130 		return ret;
1131 
1132 	mtd_ooblayout_ecc(mtd, 0, &nand->ecc);
1133 
1134 	ret = mtd_device_register(mtd, NULL, 0);
1135 	if (ret) {
1136 		dev_err(dev, "Failed to register mtd device: %d\n", ret);
1137 		nand_cleanup(chip);
1138 		return ret;
1139 	}
1140 
1141 	ctrl->chip = chip;
1142 
1143 	return 0;
1144 }
1145 
1146 static int tegra_nand_probe(struct platform_device *pdev)
1147 {
1148 	struct reset_control *rst;
1149 	struct tegra_nand_controller *ctrl;
1150 	int err = 0;
1151 
1152 	ctrl = devm_kzalloc(&pdev->dev, sizeof(*ctrl), GFP_KERNEL);
1153 	if (!ctrl)
1154 		return -ENOMEM;
1155 
1156 	ctrl->dev = &pdev->dev;
1157 	platform_set_drvdata(pdev, ctrl);
1158 	nand_controller_init(&ctrl->controller);
1159 	ctrl->controller.ops = &tegra_nand_controller_ops;
1160 
1161 	ctrl->regs = devm_platform_ioremap_resource(pdev, 0);
1162 	if (IS_ERR(ctrl->regs))
1163 		return PTR_ERR(ctrl->regs);
1164 
1165 	rst = devm_reset_control_get(&pdev->dev, "nand");
1166 	if (IS_ERR(rst))
1167 		return PTR_ERR(rst);
1168 
1169 	ctrl->clk = devm_clk_get(&pdev->dev, "nand");
1170 	if (IS_ERR(ctrl->clk))
1171 		return PTR_ERR(ctrl->clk);
1172 
1173 	err = devm_tegra_core_dev_init_opp_table_common(&pdev->dev);
1174 	if (err)
1175 		return err;
1176 
1177 	/*
1178 	 * This driver doesn't support active power management yet,
1179 	 * so we will simply keep device resumed.
1180 	 */
1181 	pm_runtime_enable(&pdev->dev);
1182 	err = pm_runtime_resume_and_get(&pdev->dev);
1183 	if (err)
1184 		goto err_dis_pm;
1185 
1186 	err = reset_control_reset(rst);
1187 	if (err) {
1188 		dev_err(ctrl->dev, "Failed to reset HW: %d\n", err);
1189 		goto err_put_pm;
1190 	}
1191 
1192 	writel_relaxed(HWSTATUS_CMD_DEFAULT, ctrl->regs + HWSTATUS_CMD);
1193 	writel_relaxed(HWSTATUS_MASK_DEFAULT, ctrl->regs + HWSTATUS_MASK);
1194 	writel_relaxed(INT_MASK, ctrl->regs + IER);
1195 
1196 	init_completion(&ctrl->command_complete);
1197 	init_completion(&ctrl->dma_complete);
1198 
1199 	ctrl->irq = platform_get_irq(pdev, 0);
1200 	if (ctrl->irq < 0) {
1201 		err = ctrl->irq;
1202 		goto err_put_pm;
1203 	}
1204 	err = devm_request_irq(&pdev->dev, ctrl->irq, tegra_nand_irq, 0,
1205 			       dev_name(&pdev->dev), ctrl);
1206 	if (err) {
1207 		dev_err(ctrl->dev, "Failed to get IRQ: %d\n", err);
1208 		goto err_put_pm;
1209 	}
1210 
1211 	writel_relaxed(DMA_MST_CTRL_IS_DONE, ctrl->regs + DMA_MST_CTRL);
1212 
1213 	err = tegra_nand_chips_init(ctrl->dev, ctrl);
1214 	if (err)
1215 		goto err_put_pm;
1216 
1217 	return 0;
1218 
1219 err_put_pm:
1220 	pm_runtime_put_sync_suspend(ctrl->dev);
1221 	pm_runtime_force_suspend(ctrl->dev);
1222 err_dis_pm:
1223 	pm_runtime_disable(&pdev->dev);
1224 	return err;
1225 }
1226 
1227 static void tegra_nand_remove(struct platform_device *pdev)
1228 {
1229 	struct tegra_nand_controller *ctrl = platform_get_drvdata(pdev);
1230 	struct nand_chip *chip = ctrl->chip;
1231 	struct mtd_info *mtd = nand_to_mtd(chip);
1232 
1233 	WARN_ON(mtd_device_unregister(mtd));
1234 
1235 	nand_cleanup(chip);
1236 
1237 	pm_runtime_put_sync_suspend(ctrl->dev);
1238 	pm_runtime_force_suspend(ctrl->dev);
1239 }
1240 
1241 static int __maybe_unused tegra_nand_runtime_resume(struct device *dev)
1242 {
1243 	struct tegra_nand_controller *ctrl = dev_get_drvdata(dev);
1244 	int err;
1245 
1246 	err = clk_prepare_enable(ctrl->clk);
1247 	if (err) {
1248 		dev_err(dev, "Failed to enable clock: %d\n", err);
1249 		return err;
1250 	}
1251 
1252 	return 0;
1253 }
1254 
1255 static int __maybe_unused tegra_nand_runtime_suspend(struct device *dev)
1256 {
1257 	struct tegra_nand_controller *ctrl = dev_get_drvdata(dev);
1258 
1259 	clk_disable_unprepare(ctrl->clk);
1260 
1261 	return 0;
1262 }
1263 
1264 static const struct dev_pm_ops tegra_nand_pm = {
1265 	SET_RUNTIME_PM_OPS(tegra_nand_runtime_suspend, tegra_nand_runtime_resume,
1266 			   NULL)
1267 };
1268 
1269 static const struct of_device_id tegra_nand_of_match[] = {
1270 	{ .compatible = "nvidia,tegra20-nand" },
1271 	{ /* sentinel */ }
1272 };
1273 MODULE_DEVICE_TABLE(of, tegra_nand_of_match);
1274 
1275 static struct platform_driver tegra_nand_driver = {
1276 	.driver = {
1277 		.name = "tegra-nand",
1278 		.of_match_table = tegra_nand_of_match,
1279 		.pm = &tegra_nand_pm,
1280 	},
1281 	.probe = tegra_nand_probe,
1282 	.remove_new = tegra_nand_remove,
1283 };
1284 module_platform_driver(tegra_nand_driver);
1285 
1286 MODULE_DESCRIPTION("NVIDIA Tegra NAND driver");
1287 MODULE_AUTHOR("Thierry Reding <thierry.reding@nvidia.com>");
1288 MODULE_AUTHOR("Lucas Stach <dev@lynxeye.de>");
1289 MODULE_AUTHOR("Stefan Agner <stefan@agner.ch>");
1290 MODULE_LICENSE("GPL v2");
1291