xref: /linux/drivers/mtd/nand/raw/omap2.c (revision 9b2ffa6148b1e4468d08f7e0e7e371c43cac9ffe)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright © 2004 Texas Instruments, Jian Zhang <jzhang@ti.com>
4  * Copyright © 2004 Micron Technology Inc.
5  * Copyright © 2004 David Brownell
6  */
7 
8 #include <linux/platform_device.h>
9 #include <linux/dmaengine.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/delay.h>
12 #include <linux/gpio/consumer.h>
13 #include <linux/module.h>
14 #include <linux/interrupt.h>
15 #include <linux/jiffies.h>
16 #include <linux/sched.h>
17 #include <linux/mtd/mtd.h>
18 #include <linux/mtd/nand-ecc-sw-bch.h>
19 #include <linux/mtd/rawnand.h>
20 #include <linux/mtd/partitions.h>
21 #include <linux/omap-dma.h>
22 #include <linux/iopoll.h>
23 #include <linux/slab.h>
24 #include <linux/of.h>
25 #include <linux/of_platform.h>
26 
27 #include <linux/platform_data/elm.h>
28 
29 #include <linux/omap-gpmc.h>
30 #include <linux/platform_data/mtd-nand-omap2.h>
31 
32 #define	DRIVER_NAME	"omap2-nand"
33 #define	OMAP_NAND_TIMEOUT_MS	5000
34 
35 #define NAND_Ecc_P1e		(1 << 0)
36 #define NAND_Ecc_P2e		(1 << 1)
37 #define NAND_Ecc_P4e		(1 << 2)
38 #define NAND_Ecc_P8e		(1 << 3)
39 #define NAND_Ecc_P16e		(1 << 4)
40 #define NAND_Ecc_P32e		(1 << 5)
41 #define NAND_Ecc_P64e		(1 << 6)
42 #define NAND_Ecc_P128e		(1 << 7)
43 #define NAND_Ecc_P256e		(1 << 8)
44 #define NAND_Ecc_P512e		(1 << 9)
45 #define NAND_Ecc_P1024e		(1 << 10)
46 #define NAND_Ecc_P2048e		(1 << 11)
47 
48 #define NAND_Ecc_P1o		(1 << 16)
49 #define NAND_Ecc_P2o		(1 << 17)
50 #define NAND_Ecc_P4o		(1 << 18)
51 #define NAND_Ecc_P8o		(1 << 19)
52 #define NAND_Ecc_P16o		(1 << 20)
53 #define NAND_Ecc_P32o		(1 << 21)
54 #define NAND_Ecc_P64o		(1 << 22)
55 #define NAND_Ecc_P128o		(1 << 23)
56 #define NAND_Ecc_P256o		(1 << 24)
57 #define NAND_Ecc_P512o		(1 << 25)
58 #define NAND_Ecc_P1024o		(1 << 26)
59 #define NAND_Ecc_P2048o		(1 << 27)
60 
61 #define TF(value)	(value ? 1 : 0)
62 
63 #define P2048e(a)	(TF(a & NAND_Ecc_P2048e)	<< 0)
64 #define P2048o(a)	(TF(a & NAND_Ecc_P2048o)	<< 1)
65 #define P1e(a)		(TF(a & NAND_Ecc_P1e)		<< 2)
66 #define P1o(a)		(TF(a & NAND_Ecc_P1o)		<< 3)
67 #define P2e(a)		(TF(a & NAND_Ecc_P2e)		<< 4)
68 #define P2o(a)		(TF(a & NAND_Ecc_P2o)		<< 5)
69 #define P4e(a)		(TF(a & NAND_Ecc_P4e)		<< 6)
70 #define P4o(a)		(TF(a & NAND_Ecc_P4o)		<< 7)
71 
72 #define P8e(a)		(TF(a & NAND_Ecc_P8e)		<< 0)
73 #define P8o(a)		(TF(a & NAND_Ecc_P8o)		<< 1)
74 #define P16e(a)		(TF(a & NAND_Ecc_P16e)		<< 2)
75 #define P16o(a)		(TF(a & NAND_Ecc_P16o)		<< 3)
76 #define P32e(a)		(TF(a & NAND_Ecc_P32e)		<< 4)
77 #define P32o(a)		(TF(a & NAND_Ecc_P32o)		<< 5)
78 #define P64e(a)		(TF(a & NAND_Ecc_P64e)		<< 6)
79 #define P64o(a)		(TF(a & NAND_Ecc_P64o)		<< 7)
80 
81 #define P128e(a)	(TF(a & NAND_Ecc_P128e)		<< 0)
82 #define P128o(a)	(TF(a & NAND_Ecc_P128o)		<< 1)
83 #define P256e(a)	(TF(a & NAND_Ecc_P256e)		<< 2)
84 #define P256o(a)	(TF(a & NAND_Ecc_P256o)		<< 3)
85 #define P512e(a)	(TF(a & NAND_Ecc_P512e)		<< 4)
86 #define P512o(a)	(TF(a & NAND_Ecc_P512o)		<< 5)
87 #define P1024e(a)	(TF(a & NAND_Ecc_P1024e)	<< 6)
88 #define P1024o(a)	(TF(a & NAND_Ecc_P1024o)	<< 7)
89 
90 #define P8e_s(a)	(TF(a & NAND_Ecc_P8e)		<< 0)
91 #define P8o_s(a)	(TF(a & NAND_Ecc_P8o)		<< 1)
92 #define P16e_s(a)	(TF(a & NAND_Ecc_P16e)		<< 2)
93 #define P16o_s(a)	(TF(a & NAND_Ecc_P16o)		<< 3)
94 #define P1e_s(a)	(TF(a & NAND_Ecc_P1e)		<< 4)
95 #define P1o_s(a)	(TF(a & NAND_Ecc_P1o)		<< 5)
96 #define P2e_s(a)	(TF(a & NAND_Ecc_P2e)		<< 6)
97 #define P2o_s(a)	(TF(a & NAND_Ecc_P2o)		<< 7)
98 
99 #define P4e_s(a)	(TF(a & NAND_Ecc_P4e)		<< 0)
100 #define P4o_s(a)	(TF(a & NAND_Ecc_P4o)		<< 1)
101 
102 #define	PREFETCH_CONFIG1_CS_SHIFT	24
103 #define	ECC_CONFIG_CS_SHIFT		1
104 #define	CS_MASK				0x7
105 #define	ENABLE_PREFETCH			(0x1 << 7)
106 #define	DMA_MPU_MODE_SHIFT		2
107 #define	ECCSIZE0_SHIFT			12
108 #define	ECCSIZE1_SHIFT			22
109 #define	ECC1RESULTSIZE			0x1
110 #define	ECCCLEAR			0x100
111 #define	ECC1				0x1
112 #define	PREFETCH_FIFOTHRESHOLD_MAX	0x40
113 #define	PREFETCH_FIFOTHRESHOLD(val)	((val) << 8)
114 #define	PREFETCH_STATUS_COUNT(val)	(val & 0x00003fff)
115 #define	PREFETCH_STATUS_FIFO_CNT(val)	((val >> 24) & 0x7F)
116 #define	STATUS_BUFF_EMPTY		0x00000001
117 
118 #define SECTOR_BYTES		512
119 /* 4 bit padding to make byte aligned, 56 = 52 + 4 */
120 #define BCH4_BIT_PAD		4
121 
122 /* GPMC ecc engine settings for read */
123 #define BCH_WRAPMODE_1		1	/* BCH wrap mode 1 */
124 #define BCH8R_ECC_SIZE0		0x1a	/* ecc_size0 = 26 */
125 #define BCH8R_ECC_SIZE1		0x2	/* ecc_size1 = 2 */
126 #define BCH4R_ECC_SIZE0		0xd	/* ecc_size0 = 13 */
127 #define BCH4R_ECC_SIZE1		0x3	/* ecc_size1 = 3 */
128 
129 /* GPMC ecc engine settings for write */
130 #define BCH_WRAPMODE_6		6	/* BCH wrap mode 6 */
131 #define BCH_ECC_SIZE0		0x0	/* ecc_size0 = 0, no oob protection */
132 #define BCH_ECC_SIZE1		0x20	/* ecc_size1 = 32 */
133 
134 #define BBM_LEN			2
135 
136 static u_char bch16_vector[] = {0xf5, 0x24, 0x1c, 0xd0, 0x61, 0xb3, 0xf1, 0x55,
137 				0x2e, 0x2c, 0x86, 0xa3, 0xed, 0x36, 0x1b, 0x78,
138 				0x48, 0x76, 0xa9, 0x3b, 0x97, 0xd1, 0x7a, 0x93,
139 				0x07, 0x0e};
140 static u_char bch8_vector[] = {0xf3, 0xdb, 0x14, 0x16, 0x8b, 0xd2, 0xbe, 0xcc,
141 	0xac, 0x6b, 0xff, 0x99, 0x7b};
142 static u_char bch4_vector[] = {0x00, 0x6b, 0x31, 0xdd, 0x41, 0xbc, 0x10};
143 
144 struct omap_nand_info {
145 	struct nand_chip		nand;
146 	struct platform_device		*pdev;
147 
148 	int				gpmc_cs;
149 	bool				dev_ready;
150 	enum nand_io			xfer_type;
151 	enum omap_ecc			ecc_opt;
152 	struct device_node		*elm_of_node;
153 
154 	unsigned long			phys_base;
155 	struct completion		comp;
156 	struct dma_chan			*dma;
157 	int				gpmc_irq_fifo;
158 	int				gpmc_irq_count;
159 	enum {
160 		OMAP_NAND_IO_READ = 0,	/* read */
161 		OMAP_NAND_IO_WRITE,	/* write */
162 	} iomode;
163 	u_char				*buf;
164 	int					buf_len;
165 	/* Interface to GPMC */
166 	void __iomem			*fifo;
167 	struct gpmc_nand_regs		reg;
168 	struct gpmc_nand_ops		*ops;
169 	bool				flash_bbt;
170 	/* fields specific for BCHx_HW ECC scheme */
171 	struct device			*elm_dev;
172 	/* NAND ready gpio */
173 	struct gpio_desc		*ready_gpiod;
174 	unsigned int			neccpg;
175 	unsigned int			nsteps_per_eccpg;
176 	unsigned int			eccpg_size;
177 	unsigned int			eccpg_bytes;
178 	void (*data_in)(struct nand_chip *chip, void *buf,
179 			unsigned int len, bool force_8bit);
180 	void (*data_out)(struct nand_chip *chip,
181 			 const void *buf, unsigned int len,
182 			 bool force_8bit);
183 };
184 
mtd_to_omap(struct mtd_info * mtd)185 static inline struct omap_nand_info *mtd_to_omap(struct mtd_info *mtd)
186 {
187 	return container_of(mtd_to_nand(mtd), struct omap_nand_info, nand);
188 }
189 
190 static void omap_nand_data_in(struct nand_chip *chip, void *buf,
191 			      unsigned int len, bool force_8bit);
192 
193 static void omap_nand_data_out(struct nand_chip *chip,
194 			       const void *buf, unsigned int len,
195 			       bool force_8bit);
196 
197 /**
198  * omap_prefetch_enable - configures and starts prefetch transfer
199  * @cs: cs (chip select) number
200  * @fifo_th: fifo threshold to be used for read/ write
201  * @dma_mode: dma mode enable (1) or disable (0)
202  * @u32_count: number of bytes to be transferred
203  * @is_write: prefetch read(0) or write post(1) mode
204  * @info: NAND device structure containing platform data
205  */
omap_prefetch_enable(int cs,int fifo_th,int dma_mode,unsigned int u32_count,int is_write,struct omap_nand_info * info)206 static int omap_prefetch_enable(int cs, int fifo_th, int dma_mode,
207 	unsigned int u32_count, int is_write, struct omap_nand_info *info)
208 {
209 	u32 val;
210 
211 	if (fifo_th > PREFETCH_FIFOTHRESHOLD_MAX)
212 		return -1;
213 
214 	if (readl(info->reg.gpmc_prefetch_control))
215 		return -EBUSY;
216 
217 	/* Set the amount of bytes to be prefetched */
218 	writel(u32_count, info->reg.gpmc_prefetch_config2);
219 
220 	/* Set dma/mpu mode, the prefetch read / post write and
221 	 * enable the engine. Set which cs is has requested for.
222 	 */
223 	val = ((cs << PREFETCH_CONFIG1_CS_SHIFT) |
224 		PREFETCH_FIFOTHRESHOLD(fifo_th) | ENABLE_PREFETCH |
225 		(dma_mode << DMA_MPU_MODE_SHIFT) | (is_write & 0x1));
226 	writel(val, info->reg.gpmc_prefetch_config1);
227 
228 	/*  Start the prefetch engine */
229 	writel(0x1, info->reg.gpmc_prefetch_control);
230 
231 	return 0;
232 }
233 
234 /*
235  * omap_prefetch_reset - disables and stops the prefetch engine
236  */
omap_prefetch_reset(int cs,struct omap_nand_info * info)237 static int omap_prefetch_reset(int cs, struct omap_nand_info *info)
238 {
239 	u32 config1;
240 
241 	/* check if the same module/cs is trying to reset */
242 	config1 = readl(info->reg.gpmc_prefetch_config1);
243 	if (((config1 >> PREFETCH_CONFIG1_CS_SHIFT) & CS_MASK) != cs)
244 		return -EINVAL;
245 
246 	/* Stop the PFPW engine */
247 	writel(0x0, info->reg.gpmc_prefetch_control);
248 
249 	/* Reset/disable the PFPW engine */
250 	writel(0x0, info->reg.gpmc_prefetch_config1);
251 
252 	return 0;
253 }
254 
255 /**
256  * omap_nand_data_in_pref - NAND data in using prefetch engine
257  * @chip: NAND chip
258  * @buf: output buffer where NAND data is placed into
259  * @len: length of transfer
260  * @force_8bit: force 8-bit transfers
261  */
omap_nand_data_in_pref(struct nand_chip * chip,void * buf,unsigned int len,bool force_8bit)262 static void omap_nand_data_in_pref(struct nand_chip *chip, void *buf,
263 				   unsigned int len, bool force_8bit)
264 {
265 	struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip));
266 	uint32_t r_count = 0;
267 	int ret = 0;
268 	u32 *p = (u32 *)buf;
269 	unsigned int pref_len;
270 
271 	if (force_8bit) {
272 		omap_nand_data_in(chip, buf, len, force_8bit);
273 		return;
274 	}
275 
276 	/* read 32-bit words using prefetch and remaining bytes normally */
277 
278 	/* configure and start prefetch transfer */
279 	pref_len = len - (len & 3);
280 	ret = omap_prefetch_enable(info->gpmc_cs,
281 			PREFETCH_FIFOTHRESHOLD_MAX, 0x0, pref_len, 0x0, info);
282 	if (ret) {
283 		/* prefetch engine is busy, use CPU copy method */
284 		omap_nand_data_in(chip, buf, len, false);
285 	} else {
286 		do {
287 			r_count = readl(info->reg.gpmc_prefetch_status);
288 			r_count = PREFETCH_STATUS_FIFO_CNT(r_count);
289 			r_count = r_count >> 2;
290 			ioread32_rep(info->fifo, p, r_count);
291 			p += r_count;
292 			pref_len -= r_count << 2;
293 		} while (pref_len);
294 		/* disable and stop the Prefetch engine */
295 		omap_prefetch_reset(info->gpmc_cs, info);
296 		/* fetch any remaining bytes */
297 		if (len & 3)
298 			omap_nand_data_in(chip, p, len & 3, false);
299 	}
300 }
301 
302 /**
303  * omap_nand_data_out_pref - NAND data out using Write Posting engine
304  * @chip: NAND chip
305  * @buf: input buffer that is sent to NAND
306  * @len: length of transfer
307  * @force_8bit: force 8-bit transfers
308  */
omap_nand_data_out_pref(struct nand_chip * chip,const void * buf,unsigned int len,bool force_8bit)309 static void omap_nand_data_out_pref(struct nand_chip *chip,
310 				    const void *buf, unsigned int len,
311 				    bool force_8bit)
312 {
313 	struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip));
314 	uint32_t w_count = 0;
315 	int i = 0, ret = 0;
316 	u16 *p = (u16 *)buf;
317 	unsigned long tim, limit;
318 	u32 val;
319 
320 	if (force_8bit) {
321 		omap_nand_data_out(chip, buf, len, force_8bit);
322 		return;
323 	}
324 
325 	/* take care of subpage writes */
326 	if (len % 2 != 0) {
327 		writeb(*(u8 *)buf, info->fifo);
328 		p = (u16 *)(buf + 1);
329 		len--;
330 	}
331 
332 	/*  configure and start prefetch transfer */
333 	ret = omap_prefetch_enable(info->gpmc_cs,
334 			PREFETCH_FIFOTHRESHOLD_MAX, 0x0, len, 0x1, info);
335 	if (ret) {
336 		/* write posting engine is busy, use CPU copy method */
337 		omap_nand_data_out(chip, buf, len, false);
338 	} else {
339 		while (len) {
340 			w_count = readl(info->reg.gpmc_prefetch_status);
341 			w_count = PREFETCH_STATUS_FIFO_CNT(w_count);
342 			w_count = w_count >> 1;
343 			for (i = 0; (i < w_count) && len; i++, len -= 2)
344 				iowrite16(*p++, info->fifo);
345 		}
346 		/* wait for data to flushed-out before reset the prefetch */
347 		tim = 0;
348 		limit = (loops_per_jiffy *
349 					msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS));
350 		do {
351 			cpu_relax();
352 			val = readl(info->reg.gpmc_prefetch_status);
353 			val = PREFETCH_STATUS_COUNT(val);
354 		} while (val && (tim++ < limit));
355 
356 		/* disable and stop the PFPW engine */
357 		omap_prefetch_reset(info->gpmc_cs, info);
358 	}
359 }
360 
361 /*
362  * omap_nand_dma_callback: callback on the completion of dma transfer
363  * @data: pointer to completion data structure
364  */
omap_nand_dma_callback(void * data)365 static void omap_nand_dma_callback(void *data)
366 {
367 	complete((struct completion *) data);
368 }
369 
370 /*
371  * omap_nand_dma_transfer: configure and start dma transfer
372  * @chip: nand chip structure
373  * @addr: virtual address in RAM of source/destination
374  * @len: number of data bytes to be transferred
375  * @is_write: flag for read/write operation
376  */
omap_nand_dma_transfer(struct nand_chip * chip,const void * addr,unsigned int len,int is_write)377 static inline int omap_nand_dma_transfer(struct nand_chip *chip,
378 					 const void *addr, unsigned int len,
379 					 int is_write)
380 {
381 	struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip));
382 	struct dma_async_tx_descriptor *tx;
383 	enum dma_data_direction dir = is_write ? DMA_TO_DEVICE :
384 							DMA_FROM_DEVICE;
385 	struct scatterlist sg;
386 	unsigned long tim, limit;
387 	unsigned n;
388 	int ret;
389 	u32 val;
390 
391 	if (!virt_addr_valid(addr))
392 		goto out_copy;
393 
394 	sg_init_one(&sg, addr, len);
395 	n = dma_map_sg(info->dma->device->dev, &sg, 1, dir);
396 	if (n == 0) {
397 		dev_err(&info->pdev->dev,
398 			"Couldn't DMA map a %d byte buffer\n", len);
399 		goto out_copy;
400 	}
401 
402 	tx = dmaengine_prep_slave_sg(info->dma, &sg, n,
403 		is_write ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM,
404 		DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
405 	if (!tx)
406 		goto out_copy_unmap;
407 
408 	tx->callback = omap_nand_dma_callback;
409 	tx->callback_param = &info->comp;
410 	dmaengine_submit(tx);
411 
412 	init_completion(&info->comp);
413 
414 	/* setup and start DMA using dma_addr */
415 	dma_async_issue_pending(info->dma);
416 
417 	/*  configure and start prefetch transfer */
418 	ret = omap_prefetch_enable(info->gpmc_cs,
419 		PREFETCH_FIFOTHRESHOLD_MAX, 0x1, len, is_write, info);
420 	if (ret)
421 		/* PFPW engine is busy, use cpu copy method */
422 		goto out_copy_unmap;
423 
424 	wait_for_completion(&info->comp);
425 	tim = 0;
426 	limit = (loops_per_jiffy * msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS));
427 
428 	do {
429 		cpu_relax();
430 		val = readl(info->reg.gpmc_prefetch_status);
431 		val = PREFETCH_STATUS_COUNT(val);
432 	} while (val && (tim++ < limit));
433 
434 	/* disable and stop the PFPW engine */
435 	omap_prefetch_reset(info->gpmc_cs, info);
436 
437 	dma_unmap_sg(info->dma->device->dev, &sg, 1, dir);
438 	return 0;
439 
440 out_copy_unmap:
441 	dma_unmap_sg(info->dma->device->dev, &sg, 1, dir);
442 out_copy:
443 	is_write == 0 ? omap_nand_data_in(chip, (void *)addr, len, false)
444 		      : omap_nand_data_out(chip, addr, len, false);
445 
446 	return 0;
447 }
448 
449 /**
450  * omap_nand_data_in_dma_pref - NAND data in using DMA and Prefetch
451  * @chip: NAND chip
452  * @buf: output buffer where NAND data is placed into
453  * @len: length of transfer
454  * @force_8bit: force 8-bit transfers
455  */
omap_nand_data_in_dma_pref(struct nand_chip * chip,void * buf,unsigned int len,bool force_8bit)456 static void omap_nand_data_in_dma_pref(struct nand_chip *chip, void *buf,
457 				       unsigned int len, bool force_8bit)
458 {
459 	struct mtd_info *mtd = nand_to_mtd(chip);
460 
461 	if (force_8bit) {
462 		omap_nand_data_in(chip, buf, len, force_8bit);
463 		return;
464 	}
465 
466 	if (len <= mtd->oobsize)
467 		omap_nand_data_in_pref(chip, buf, len, false);
468 	else
469 		/* start transfer in DMA mode */
470 		omap_nand_dma_transfer(chip, buf, len, 0x0);
471 }
472 
473 /**
474  * omap_nand_data_out_dma_pref - NAND data out using DMA and write posting
475  * @chip: NAND chip
476  * @buf: input buffer that is sent to NAND
477  * @len: length of transfer
478  * @force_8bit: force 8-bit transfers
479  */
omap_nand_data_out_dma_pref(struct nand_chip * chip,const void * buf,unsigned int len,bool force_8bit)480 static void omap_nand_data_out_dma_pref(struct nand_chip *chip,
481 					const void *buf, unsigned int len,
482 					bool force_8bit)
483 {
484 	struct mtd_info *mtd = nand_to_mtd(chip);
485 
486 	if (force_8bit) {
487 		omap_nand_data_out(chip, buf, len, force_8bit);
488 		return;
489 	}
490 
491 	if (len <= mtd->oobsize)
492 		omap_nand_data_out_pref(chip, buf, len, false);
493 	else
494 		/* start transfer in DMA mode */
495 		omap_nand_dma_transfer(chip, buf, len, 0x1);
496 }
497 
498 /*
499  * omap_nand_irq - GPMC irq handler
500  * @this_irq: gpmc irq number
501  * @dev: omap_nand_info structure pointer is passed here
502  */
omap_nand_irq(int this_irq,void * dev)503 static irqreturn_t omap_nand_irq(int this_irq, void *dev)
504 {
505 	struct omap_nand_info *info = (struct omap_nand_info *) dev;
506 	u32 bytes;
507 
508 	bytes = readl(info->reg.gpmc_prefetch_status);
509 	bytes = PREFETCH_STATUS_FIFO_CNT(bytes);
510 	bytes = bytes  & 0xFFFC; /* io in multiple of 4 bytes */
511 	if (info->iomode == OMAP_NAND_IO_WRITE) { /* checks for write io */
512 		if (this_irq == info->gpmc_irq_count)
513 			goto done;
514 
515 		if (info->buf_len && (info->buf_len < bytes))
516 			bytes = info->buf_len;
517 		else if (!info->buf_len)
518 			bytes = 0;
519 		iowrite32_rep(info->fifo, (u32 *)info->buf,
520 			      bytes >> 2);
521 		info->buf = info->buf + bytes;
522 		info->buf_len -= bytes;
523 
524 	} else {
525 		ioread32_rep(info->fifo, (u32 *)info->buf,
526 			     bytes >> 2);
527 		info->buf = info->buf + bytes;
528 
529 		if (this_irq == info->gpmc_irq_count)
530 			goto done;
531 	}
532 
533 	return IRQ_HANDLED;
534 
535 done:
536 	complete(&info->comp);
537 
538 	disable_irq_nosync(info->gpmc_irq_fifo);
539 	disable_irq_nosync(info->gpmc_irq_count);
540 
541 	return IRQ_HANDLED;
542 }
543 
544 /*
545  * omap_nand_data_in_irq_pref - NAND data in using Prefetch and IRQ
546  */
omap_nand_data_in_irq_pref(struct nand_chip * chip,void * buf,unsigned int len,bool force_8bit)547 static void omap_nand_data_in_irq_pref(struct nand_chip *chip, void *buf,
548 				       unsigned int len, bool force_8bit)
549 {
550 	struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip));
551 	struct mtd_info *mtd = nand_to_mtd(&info->nand);
552 	int ret = 0;
553 
554 	if (len <= mtd->oobsize || force_8bit) {
555 		omap_nand_data_in(chip, buf, len, force_8bit);
556 		return;
557 	}
558 
559 	info->iomode = OMAP_NAND_IO_READ;
560 	info->buf = buf;
561 	init_completion(&info->comp);
562 
563 	/*  configure and start prefetch transfer */
564 	ret = omap_prefetch_enable(info->gpmc_cs,
565 			PREFETCH_FIFOTHRESHOLD_MAX/2, 0x0, len, 0x0, info);
566 	if (ret) {
567 		/* PFPW engine is busy, use cpu copy method */
568 		omap_nand_data_in(chip, buf, len, false);
569 		return;
570 	}
571 
572 	info->buf_len = len;
573 
574 	enable_irq(info->gpmc_irq_count);
575 	enable_irq(info->gpmc_irq_fifo);
576 
577 	/* waiting for read to complete */
578 	wait_for_completion(&info->comp);
579 
580 	/* disable and stop the PFPW engine */
581 	omap_prefetch_reset(info->gpmc_cs, info);
582 	return;
583 }
584 
585 /*
586  * omap_nand_data_out_irq_pref - NAND out using write posting and IRQ
587  */
omap_nand_data_out_irq_pref(struct nand_chip * chip,const void * buf,unsigned int len,bool force_8bit)588 static void omap_nand_data_out_irq_pref(struct nand_chip *chip,
589 					const void *buf, unsigned int len,
590 					bool force_8bit)
591 {
592 	struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip));
593 	struct mtd_info *mtd = nand_to_mtd(&info->nand);
594 	int ret = 0;
595 	unsigned long tim, limit;
596 	u32 val;
597 
598 	if (len <= mtd->oobsize || force_8bit) {
599 		omap_nand_data_out(chip, buf, len, force_8bit);
600 		return;
601 	}
602 
603 	info->iomode = OMAP_NAND_IO_WRITE;
604 	info->buf = (u_char *) buf;
605 	init_completion(&info->comp);
606 
607 	/* configure and start prefetch transfer : size=24 */
608 	ret = omap_prefetch_enable(info->gpmc_cs,
609 		(PREFETCH_FIFOTHRESHOLD_MAX * 3) / 8, 0x0, len, 0x1, info);
610 	if (ret) {
611 		/* PFPW engine is busy, use cpu copy method */
612 		omap_nand_data_out(chip, buf, len, false);
613 		return;
614 	}
615 
616 	info->buf_len = len;
617 
618 	enable_irq(info->gpmc_irq_count);
619 	enable_irq(info->gpmc_irq_fifo);
620 
621 	/* waiting for write to complete */
622 	wait_for_completion(&info->comp);
623 
624 	/* wait for data to flushed-out before reset the prefetch */
625 	tim = 0;
626 	limit = (loops_per_jiffy *  msecs_to_jiffies(OMAP_NAND_TIMEOUT_MS));
627 	do {
628 		val = readl(info->reg.gpmc_prefetch_status);
629 		val = PREFETCH_STATUS_COUNT(val);
630 		cpu_relax();
631 	} while (val && (tim++ < limit));
632 
633 	/* disable and stop the PFPW engine */
634 	omap_prefetch_reset(info->gpmc_cs, info);
635 	return;
636 }
637 
638 /**
639  * gen_true_ecc - This function will generate true ECC value
640  * @ecc_buf: buffer to store ecc code
641  *
642  * This generated true ECC value can be used when correcting
643  * data read from NAND flash memory core
644  */
gen_true_ecc(u8 * ecc_buf)645 static void gen_true_ecc(u8 *ecc_buf)
646 {
647 	u32 tmp = ecc_buf[0] | (ecc_buf[1] << 16) |
648 		((ecc_buf[2] & 0xF0) << 20) | ((ecc_buf[2] & 0x0F) << 8);
649 
650 	ecc_buf[0] = ~(P64o(tmp) | P64e(tmp) | P32o(tmp) | P32e(tmp) |
651 			P16o(tmp) | P16e(tmp) | P8o(tmp) | P8e(tmp));
652 	ecc_buf[1] = ~(P1024o(tmp) | P1024e(tmp) | P512o(tmp) | P512e(tmp) |
653 			P256o(tmp) | P256e(tmp) | P128o(tmp) | P128e(tmp));
654 	ecc_buf[2] = ~(P4o(tmp) | P4e(tmp) | P2o(tmp) | P2e(tmp) | P1o(tmp) |
655 			P1e(tmp) | P2048o(tmp) | P2048e(tmp));
656 }
657 
658 /**
659  * omap_compare_ecc - Detect (2 bits) and correct (1 bit) error in data
660  * @ecc_data1:  ecc code from nand spare area
661  * @ecc_data2:  ecc code from hardware register obtained from hardware ecc
662  * @page_data:  page data
663  *
664  * This function compares two ECC's and indicates if there is an error.
665  * If the error can be corrected it will be corrected to the buffer.
666  * If there is no error, %0 is returned. If there is an error but it
667  * was corrected, %1 is returned. Otherwise, %-1 is returned.
668  */
omap_compare_ecc(u8 * ecc_data1,u8 * ecc_data2,u8 * page_data)669 static int omap_compare_ecc(u8 *ecc_data1,	/* read from NAND memory */
670 			    u8 *ecc_data2,	/* read from register */
671 			    u8 *page_data)
672 {
673 	uint	i;
674 	u8	tmp0_bit[8], tmp1_bit[8], tmp2_bit[8];
675 	u8	comp0_bit[8], comp1_bit[8], comp2_bit[8];
676 	u8	ecc_bit[24];
677 	u8	ecc_sum = 0;
678 	u8	find_bit = 0;
679 	uint	find_byte = 0;
680 	int	isEccFF;
681 
682 	isEccFF = ((*(u32 *)ecc_data1 & 0xFFFFFF) == 0xFFFFFF);
683 
684 	gen_true_ecc(ecc_data1);
685 	gen_true_ecc(ecc_data2);
686 
687 	for (i = 0; i <= 2; i++) {
688 		*(ecc_data1 + i) = ~(*(ecc_data1 + i));
689 		*(ecc_data2 + i) = ~(*(ecc_data2 + i));
690 	}
691 
692 	for (i = 0; i < 8; i++) {
693 		tmp0_bit[i]     = *ecc_data1 % 2;
694 		*ecc_data1	= *ecc_data1 / 2;
695 	}
696 
697 	for (i = 0; i < 8; i++) {
698 		tmp1_bit[i]	 = *(ecc_data1 + 1) % 2;
699 		*(ecc_data1 + 1) = *(ecc_data1 + 1) / 2;
700 	}
701 
702 	for (i = 0; i < 8; i++) {
703 		tmp2_bit[i]	 = *(ecc_data1 + 2) % 2;
704 		*(ecc_data1 + 2) = *(ecc_data1 + 2) / 2;
705 	}
706 
707 	for (i = 0; i < 8; i++) {
708 		comp0_bit[i]     = *ecc_data2 % 2;
709 		*ecc_data2       = *ecc_data2 / 2;
710 	}
711 
712 	for (i = 0; i < 8; i++) {
713 		comp1_bit[i]     = *(ecc_data2 + 1) % 2;
714 		*(ecc_data2 + 1) = *(ecc_data2 + 1) / 2;
715 	}
716 
717 	for (i = 0; i < 8; i++) {
718 		comp2_bit[i]     = *(ecc_data2 + 2) % 2;
719 		*(ecc_data2 + 2) = *(ecc_data2 + 2) / 2;
720 	}
721 
722 	for (i = 0; i < 6; i++)
723 		ecc_bit[i] = tmp2_bit[i + 2] ^ comp2_bit[i + 2];
724 
725 	for (i = 0; i < 8; i++)
726 		ecc_bit[i + 6] = tmp0_bit[i] ^ comp0_bit[i];
727 
728 	for (i = 0; i < 8; i++)
729 		ecc_bit[i + 14] = tmp1_bit[i] ^ comp1_bit[i];
730 
731 	ecc_bit[22] = tmp2_bit[0] ^ comp2_bit[0];
732 	ecc_bit[23] = tmp2_bit[1] ^ comp2_bit[1];
733 
734 	for (i = 0; i < 24; i++)
735 		ecc_sum += ecc_bit[i];
736 
737 	switch (ecc_sum) {
738 	case 0:
739 		/* Not reached because this function is not called if
740 		 *  ECC values are equal
741 		 */
742 		return 0;
743 
744 	case 1:
745 		/* Uncorrectable error */
746 		pr_debug("ECC UNCORRECTED_ERROR 1\n");
747 		return -EBADMSG;
748 
749 	case 11:
750 		/* UN-Correctable error */
751 		pr_debug("ECC UNCORRECTED_ERROR B\n");
752 		return -EBADMSG;
753 
754 	case 12:
755 		/* Correctable error */
756 		find_byte = (ecc_bit[23] << 8) +
757 			    (ecc_bit[21] << 7) +
758 			    (ecc_bit[19] << 6) +
759 			    (ecc_bit[17] << 5) +
760 			    (ecc_bit[15] << 4) +
761 			    (ecc_bit[13] << 3) +
762 			    (ecc_bit[11] << 2) +
763 			    (ecc_bit[9]  << 1) +
764 			    ecc_bit[7];
765 
766 		find_bit = (ecc_bit[5] << 2) + (ecc_bit[3] << 1) + ecc_bit[1];
767 
768 		pr_debug("Correcting single bit ECC error at offset: "
769 				"%d, bit: %d\n", find_byte, find_bit);
770 
771 		page_data[find_byte] ^= (1 << find_bit);
772 
773 		return 1;
774 	default:
775 		if (isEccFF) {
776 			if (ecc_data2[0] == 0 &&
777 			    ecc_data2[1] == 0 &&
778 			    ecc_data2[2] == 0)
779 				return 0;
780 		}
781 		pr_debug("UNCORRECTED_ERROR default\n");
782 		return -EBADMSG;
783 	}
784 }
785 
786 /**
787  * omap_correct_data - Compares the ECC read with HW generated ECC
788  * @chip: NAND chip object
789  * @dat: page data
790  * @read_ecc: ecc read from nand flash
791  * @calc_ecc: ecc read from HW ECC registers
792  *
793  * Compares the ecc read from nand spare area with ECC registers values
794  * and if ECC's mismatched, it will call 'omap_compare_ecc' for error
795  * detection and correction. If there are no errors, %0 is returned. If
796  * there were errors and all of the errors were corrected, the number of
797  * corrected errors is returned. If uncorrectable errors exist, %-1 is
798  * returned.
799  */
omap_correct_data(struct nand_chip * chip,u_char * dat,u_char * read_ecc,u_char * calc_ecc)800 static int omap_correct_data(struct nand_chip *chip, u_char *dat,
801 			     u_char *read_ecc, u_char *calc_ecc)
802 {
803 	struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip));
804 	int blockCnt = 0, i = 0, ret = 0;
805 	int stat = 0;
806 
807 	/* Ex NAND_ECC_HW12_2048 */
808 	if (info->nand.ecc.engine_type == NAND_ECC_ENGINE_TYPE_ON_HOST &&
809 	    info->nand.ecc.size == 2048)
810 		blockCnt = 4;
811 	else
812 		blockCnt = 1;
813 
814 	for (i = 0; i < blockCnt; i++) {
815 		if (memcmp(read_ecc, calc_ecc, 3) != 0) {
816 			ret = omap_compare_ecc(read_ecc, calc_ecc, dat);
817 			if (ret < 0)
818 				return ret;
819 			/* keep track of the number of corrected errors */
820 			stat += ret;
821 		}
822 		read_ecc += 3;
823 		calc_ecc += 3;
824 		dat      += 512;
825 	}
826 	return stat;
827 }
828 
829 /**
830  * omap_calculate_ecc - Generate non-inverted ECC bytes.
831  * @chip: NAND chip object
832  * @dat: The pointer to data on which ecc is computed
833  * @ecc_code: The ecc_code buffer
834  *
835  * Using noninverted ECC can be considered ugly since writing a blank
836  * page ie. padding will clear the ECC bytes. This is no problem as long
837  * nobody is trying to write data on the seemingly unused page. Reading
838  * an erased page will produce an ECC mismatch between generated and read
839  * ECC bytes that has to be dealt with separately.
840  */
omap_calculate_ecc(struct nand_chip * chip,const u_char * dat,u_char * ecc_code)841 static int omap_calculate_ecc(struct nand_chip *chip, const u_char *dat,
842 			      u_char *ecc_code)
843 {
844 	struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip));
845 	u32 val;
846 
847 	val = readl(info->reg.gpmc_ecc_config);
848 	if (((val >> ECC_CONFIG_CS_SHIFT) & CS_MASK) != info->gpmc_cs)
849 		return -EINVAL;
850 
851 	/* read ecc result */
852 	val = readl(info->reg.gpmc_ecc1_result);
853 	*ecc_code++ = val;          /* P128e, ..., P1e */
854 	*ecc_code++ = val >> 16;    /* P128o, ..., P1o */
855 	/* P2048o, P1024o, P512o, P256o, P2048e, P1024e, P512e, P256e */
856 	*ecc_code++ = ((val >> 8) & 0x0f) | ((val >> 20) & 0xf0);
857 
858 	return 0;
859 }
860 
861 /**
862  * omap_enable_hwecc - This function enables the hardware ecc functionality
863  * @chip: NAND chip object
864  * @mode: Read/Write mode
865  */
omap_enable_hwecc(struct nand_chip * chip,int mode)866 static void omap_enable_hwecc(struct nand_chip *chip, int mode)
867 {
868 	struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip));
869 	unsigned int dev_width = (chip->options & NAND_BUSWIDTH_16) ? 1 : 0;
870 	u32 val;
871 
872 	/* clear ecc and enable bits */
873 	val = ECCCLEAR | ECC1;
874 	writel(val, info->reg.gpmc_ecc_control);
875 
876 	/* program ecc and result sizes */
877 	val = ((((info->nand.ecc.size >> 1) - 1) << ECCSIZE1_SHIFT) |
878 			 ECC1RESULTSIZE);
879 	writel(val, info->reg.gpmc_ecc_size_config);
880 
881 	switch (mode) {
882 	case NAND_ECC_READ:
883 	case NAND_ECC_WRITE:
884 		writel(ECCCLEAR | ECC1, info->reg.gpmc_ecc_control);
885 		break;
886 	case NAND_ECC_READSYN:
887 		writel(ECCCLEAR, info->reg.gpmc_ecc_control);
888 		break;
889 	default:
890 		dev_info(&info->pdev->dev,
891 			"error: unrecognized Mode[%d]!\n", mode);
892 		break;
893 	}
894 
895 	/* (ECC 16 or 8 bit col) | ( CS  )  | ECC Enable */
896 	val = (dev_width << 7) | (info->gpmc_cs << 1) | (0x1);
897 	writel(val, info->reg.gpmc_ecc_config);
898 }
899 
900 /**
901  * omap_enable_hwecc_bch - Program GPMC to perform BCH ECC calculation
902  * @chip: NAND chip object
903  * @mode: Read/Write mode
904  *
905  * When using BCH with SW correction (i.e. no ELM), sector size is set
906  * to 512 bytes and we use BCH_WRAPMODE_6 wrapping mode
907  * for both reading and writing with:
908  * eccsize0 = 0  (no additional protected byte in spare area)
909  * eccsize1 = 32 (skip 32 nibbles = 16 bytes per sector in spare area)
910  */
omap_enable_hwecc_bch(struct nand_chip * chip,int mode)911 static void __maybe_unused omap_enable_hwecc_bch(struct nand_chip *chip,
912 						 int mode)
913 {
914 	unsigned int bch_type;
915 	unsigned int dev_width, nsectors;
916 	struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip));
917 	enum omap_ecc ecc_opt = info->ecc_opt;
918 	u32 val, wr_mode;
919 	unsigned int ecc_size1, ecc_size0;
920 
921 	/* GPMC configurations for calculating ECC */
922 	switch (ecc_opt) {
923 	case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW:
924 		bch_type = 0;
925 		nsectors = 1;
926 		wr_mode	  = BCH_WRAPMODE_6;
927 		ecc_size0 = BCH_ECC_SIZE0;
928 		ecc_size1 = BCH_ECC_SIZE1;
929 		break;
930 	case OMAP_ECC_BCH4_CODE_HW:
931 		bch_type = 0;
932 		nsectors = chip->ecc.steps;
933 		if (mode == NAND_ECC_READ) {
934 			wr_mode	  = BCH_WRAPMODE_1;
935 			ecc_size0 = BCH4R_ECC_SIZE0;
936 			ecc_size1 = BCH4R_ECC_SIZE1;
937 		} else {
938 			wr_mode   = BCH_WRAPMODE_6;
939 			ecc_size0 = BCH_ECC_SIZE0;
940 			ecc_size1 = BCH_ECC_SIZE1;
941 		}
942 		break;
943 	case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
944 		bch_type = 1;
945 		nsectors = 1;
946 		wr_mode	  = BCH_WRAPMODE_6;
947 		ecc_size0 = BCH_ECC_SIZE0;
948 		ecc_size1 = BCH_ECC_SIZE1;
949 		break;
950 	case OMAP_ECC_BCH8_CODE_HW:
951 		bch_type = 1;
952 		nsectors = chip->ecc.steps;
953 		if (mode == NAND_ECC_READ) {
954 			wr_mode	  = BCH_WRAPMODE_1;
955 			ecc_size0 = BCH8R_ECC_SIZE0;
956 			ecc_size1 = BCH8R_ECC_SIZE1;
957 		} else {
958 			wr_mode   = BCH_WRAPMODE_6;
959 			ecc_size0 = BCH_ECC_SIZE0;
960 			ecc_size1 = BCH_ECC_SIZE1;
961 		}
962 		break;
963 	case OMAP_ECC_BCH16_CODE_HW:
964 		bch_type = 0x2;
965 		nsectors = chip->ecc.steps;
966 		if (mode == NAND_ECC_READ) {
967 			wr_mode	  = 0x01;
968 			ecc_size0 = 52; /* ECC bits in nibbles per sector */
969 			ecc_size1 = 0;  /* non-ECC bits in nibbles per sector */
970 		} else {
971 			wr_mode	  = 0x01;
972 			ecc_size0 = 0;  /* extra bits in nibbles per sector */
973 			ecc_size1 = 52; /* OOB bits in nibbles per sector */
974 		}
975 		break;
976 	default:
977 		return;
978 	}
979 
980 	writel(ECC1, info->reg.gpmc_ecc_control);
981 
982 	/* Configure ecc size for BCH */
983 	val = (ecc_size1 << ECCSIZE1_SHIFT) | (ecc_size0 << ECCSIZE0_SHIFT);
984 	writel(val, info->reg.gpmc_ecc_size_config);
985 
986 	dev_width = (chip->options & NAND_BUSWIDTH_16) ? 1 : 0;
987 
988 	/* BCH configuration */
989 	val = ((1                        << 16) | /* enable BCH */
990 	       (bch_type		 << 12) | /* BCH4/BCH8/BCH16 */
991 	       (wr_mode                  <<  8) | /* wrap mode */
992 	       (dev_width                <<  7) | /* bus width */
993 	       (((nsectors-1) & 0x7)     <<  4) | /* number of sectors */
994 	       (info->gpmc_cs            <<  1) | /* ECC CS */
995 	       (0x1));                            /* enable ECC */
996 
997 	writel(val, info->reg.gpmc_ecc_config);
998 
999 	/* Clear ecc and enable bits */
1000 	writel(ECCCLEAR | ECC1, info->reg.gpmc_ecc_control);
1001 }
1002 
1003 static u8  bch4_polynomial[] = {0x28, 0x13, 0xcc, 0x39, 0x96, 0xac, 0x7f};
1004 static u8  bch8_polynomial[] = {0xef, 0x51, 0x2e, 0x09, 0xed, 0x93, 0x9a, 0xc2,
1005 				0x97, 0x79, 0xe5, 0x24, 0xb5};
1006 
1007 /**
1008  * _omap_calculate_ecc_bch - Generate ECC bytes for one sector
1009  * @mtd:	MTD device structure
1010  * @dat:	The pointer to data on which ecc is computed
1011  * @ecc_calc:	The ecc_code buffer
1012  * @i:		The sector number (for a multi sector page)
1013  *
1014  * Support calculating of BCH4/8/16 ECC vectors for one sector
1015  * within a page. Sector number is in @i.
1016  */
_omap_calculate_ecc_bch(struct mtd_info * mtd,const u_char * dat,u_char * ecc_calc,int i)1017 static int _omap_calculate_ecc_bch(struct mtd_info *mtd,
1018 				   const u_char *dat, u_char *ecc_calc, int i)
1019 {
1020 	struct omap_nand_info *info = mtd_to_omap(mtd);
1021 	int eccbytes	= info->nand.ecc.bytes;
1022 	struct gpmc_nand_regs	*gpmc_regs = &info->reg;
1023 	u8 *ecc_code;
1024 	unsigned long bch_val1, bch_val2, bch_val3, bch_val4;
1025 	u32 val;
1026 	int j;
1027 
1028 	ecc_code = ecc_calc;
1029 	switch (info->ecc_opt) {
1030 	case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
1031 	case OMAP_ECC_BCH8_CODE_HW:
1032 		bch_val1 = readl(gpmc_regs->gpmc_bch_result0[i]);
1033 		bch_val2 = readl(gpmc_regs->gpmc_bch_result1[i]);
1034 		bch_val3 = readl(gpmc_regs->gpmc_bch_result2[i]);
1035 		bch_val4 = readl(gpmc_regs->gpmc_bch_result3[i]);
1036 		*ecc_code++ = (bch_val4 & 0xFF);
1037 		*ecc_code++ = ((bch_val3 >> 24) & 0xFF);
1038 		*ecc_code++ = ((bch_val3 >> 16) & 0xFF);
1039 		*ecc_code++ = ((bch_val3 >> 8) & 0xFF);
1040 		*ecc_code++ = (bch_val3 & 0xFF);
1041 		*ecc_code++ = ((bch_val2 >> 24) & 0xFF);
1042 		*ecc_code++ = ((bch_val2 >> 16) & 0xFF);
1043 		*ecc_code++ = ((bch_val2 >> 8) & 0xFF);
1044 		*ecc_code++ = (bch_val2 & 0xFF);
1045 		*ecc_code++ = ((bch_val1 >> 24) & 0xFF);
1046 		*ecc_code++ = ((bch_val1 >> 16) & 0xFF);
1047 		*ecc_code++ = ((bch_val1 >> 8) & 0xFF);
1048 		*ecc_code++ = (bch_val1 & 0xFF);
1049 		break;
1050 	case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW:
1051 	case OMAP_ECC_BCH4_CODE_HW:
1052 		bch_val1 = readl(gpmc_regs->gpmc_bch_result0[i]);
1053 		bch_val2 = readl(gpmc_regs->gpmc_bch_result1[i]);
1054 		*ecc_code++ = ((bch_val2 >> 12) & 0xFF);
1055 		*ecc_code++ = ((bch_val2 >> 4) & 0xFF);
1056 		*ecc_code++ = ((bch_val2 & 0xF) << 4) |
1057 			((bch_val1 >> 28) & 0xF);
1058 		*ecc_code++ = ((bch_val1 >> 20) & 0xFF);
1059 		*ecc_code++ = ((bch_val1 >> 12) & 0xFF);
1060 		*ecc_code++ = ((bch_val1 >> 4) & 0xFF);
1061 		*ecc_code++ = ((bch_val1 & 0xF) << 4);
1062 		break;
1063 	case OMAP_ECC_BCH16_CODE_HW:
1064 		val = readl(gpmc_regs->gpmc_bch_result6[i]);
1065 		ecc_code[0]  = ((val >>  8) & 0xFF);
1066 		ecc_code[1]  = ((val >>  0) & 0xFF);
1067 		val = readl(gpmc_regs->gpmc_bch_result5[i]);
1068 		ecc_code[2]  = ((val >> 24) & 0xFF);
1069 		ecc_code[3]  = ((val >> 16) & 0xFF);
1070 		ecc_code[4]  = ((val >>  8) & 0xFF);
1071 		ecc_code[5]  = ((val >>  0) & 0xFF);
1072 		val = readl(gpmc_regs->gpmc_bch_result4[i]);
1073 		ecc_code[6]  = ((val >> 24) & 0xFF);
1074 		ecc_code[7]  = ((val >> 16) & 0xFF);
1075 		ecc_code[8]  = ((val >>  8) & 0xFF);
1076 		ecc_code[9]  = ((val >>  0) & 0xFF);
1077 		val = readl(gpmc_regs->gpmc_bch_result3[i]);
1078 		ecc_code[10] = ((val >> 24) & 0xFF);
1079 		ecc_code[11] = ((val >> 16) & 0xFF);
1080 		ecc_code[12] = ((val >>  8) & 0xFF);
1081 		ecc_code[13] = ((val >>  0) & 0xFF);
1082 		val = readl(gpmc_regs->gpmc_bch_result2[i]);
1083 		ecc_code[14] = ((val >> 24) & 0xFF);
1084 		ecc_code[15] = ((val >> 16) & 0xFF);
1085 		ecc_code[16] = ((val >>  8) & 0xFF);
1086 		ecc_code[17] = ((val >>  0) & 0xFF);
1087 		val = readl(gpmc_regs->gpmc_bch_result1[i]);
1088 		ecc_code[18] = ((val >> 24) & 0xFF);
1089 		ecc_code[19] = ((val >> 16) & 0xFF);
1090 		ecc_code[20] = ((val >>  8) & 0xFF);
1091 		ecc_code[21] = ((val >>  0) & 0xFF);
1092 		val = readl(gpmc_regs->gpmc_bch_result0[i]);
1093 		ecc_code[22] = ((val >> 24) & 0xFF);
1094 		ecc_code[23] = ((val >> 16) & 0xFF);
1095 		ecc_code[24] = ((val >>  8) & 0xFF);
1096 		ecc_code[25] = ((val >>  0) & 0xFF);
1097 		break;
1098 	default:
1099 		return -EINVAL;
1100 	}
1101 
1102 	/* ECC scheme specific syndrome customizations */
1103 	switch (info->ecc_opt) {
1104 	case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW:
1105 		/* Add constant polynomial to remainder, so that
1106 		 * ECC of blank pages results in 0x0 on reading back
1107 		 */
1108 		for (j = 0; j < eccbytes; j++)
1109 			ecc_calc[j] ^= bch4_polynomial[j];
1110 		break;
1111 	case OMAP_ECC_BCH4_CODE_HW:
1112 		/* Set  8th ECC byte as 0x0 for ROM compatibility */
1113 		ecc_calc[eccbytes - 1] = 0x0;
1114 		break;
1115 	case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
1116 		/* Add constant polynomial to remainder, so that
1117 		 * ECC of blank pages results in 0x0 on reading back
1118 		 */
1119 		for (j = 0; j < eccbytes; j++)
1120 			ecc_calc[j] ^= bch8_polynomial[j];
1121 		break;
1122 	case OMAP_ECC_BCH8_CODE_HW:
1123 		/* Set 14th ECC byte as 0x0 for ROM compatibility */
1124 		ecc_calc[eccbytes - 1] = 0x0;
1125 		break;
1126 	case OMAP_ECC_BCH16_CODE_HW:
1127 		break;
1128 	default:
1129 		return -EINVAL;
1130 	}
1131 
1132 	return 0;
1133 }
1134 
1135 /**
1136  * omap_calculate_ecc_bch_sw - ECC generator for sector for SW based correction
1137  * @chip:	NAND chip object
1138  * @dat:	The pointer to data on which ecc is computed
1139  * @ecc_calc:	Buffer storing the calculated ECC bytes
1140  *
1141  * Support calculating of BCH4/8/16 ECC vectors for one sector. This is used
1142  * when SW based correction is required as ECC is required for one sector
1143  * at a time.
1144  */
omap_calculate_ecc_bch_sw(struct nand_chip * chip,const u_char * dat,u_char * ecc_calc)1145 static int omap_calculate_ecc_bch_sw(struct nand_chip *chip,
1146 				     const u_char *dat, u_char *ecc_calc)
1147 {
1148 	return _omap_calculate_ecc_bch(nand_to_mtd(chip), dat, ecc_calc, 0);
1149 }
1150 
1151 /**
1152  * omap_calculate_ecc_bch_multi - Generate ECC for multiple sectors
1153  * @mtd:	MTD device structure
1154  * @dat:	The pointer to data on which ecc is computed
1155  * @ecc_calc:	Buffer storing the calculated ECC bytes
1156  *
1157  * Support calculating of BCH4/8/16 ecc vectors for the entire page in one go.
1158  */
omap_calculate_ecc_bch_multi(struct mtd_info * mtd,const u_char * dat,u_char * ecc_calc)1159 static int omap_calculate_ecc_bch_multi(struct mtd_info *mtd,
1160 					const u_char *dat, u_char *ecc_calc)
1161 {
1162 	struct omap_nand_info *info = mtd_to_omap(mtd);
1163 	int eccbytes = info->nand.ecc.bytes;
1164 	unsigned long nsectors;
1165 	int i, ret;
1166 
1167 	nsectors = ((readl(info->reg.gpmc_ecc_config) >> 4) & 0x7) + 1;
1168 	for (i = 0; i < nsectors; i++) {
1169 		ret = _omap_calculate_ecc_bch(mtd, dat, ecc_calc, i);
1170 		if (ret)
1171 			return ret;
1172 
1173 		ecc_calc += eccbytes;
1174 	}
1175 
1176 	return 0;
1177 }
1178 
1179 /**
1180  * erased_sector_bitflips - count bit flips
1181  * @data:	data sector buffer
1182  * @oob:	oob buffer
1183  * @info:	omap_nand_info
1184  *
1185  * Check the bit flips in erased page falls below correctable level.
1186  * If falls below, report the page as erased with correctable bit
1187  * flip, else report as uncorrectable page.
1188  */
erased_sector_bitflips(u_char * data,u_char * oob,struct omap_nand_info * info)1189 static int erased_sector_bitflips(u_char *data, u_char *oob,
1190 		struct omap_nand_info *info)
1191 {
1192 	int flip_bits = 0, i;
1193 
1194 	for (i = 0; i < info->nand.ecc.size; i++) {
1195 		flip_bits += hweight8(~data[i]);
1196 		if (flip_bits > info->nand.ecc.strength)
1197 			return 0;
1198 	}
1199 
1200 	for (i = 0; i < info->nand.ecc.bytes - 1; i++) {
1201 		flip_bits += hweight8(~oob[i]);
1202 		if (flip_bits > info->nand.ecc.strength)
1203 			return 0;
1204 	}
1205 
1206 	/*
1207 	 * Bit flips falls in correctable level.
1208 	 * Fill data area with 0xFF
1209 	 */
1210 	if (flip_bits) {
1211 		memset(data, 0xFF, info->nand.ecc.size);
1212 		memset(oob, 0xFF, info->nand.ecc.bytes);
1213 	}
1214 
1215 	return flip_bits;
1216 }
1217 
1218 /**
1219  * omap_elm_correct_data - corrects page data area in case error reported
1220  * @chip:	NAND chip object
1221  * @data:	page data
1222  * @read_ecc:	ecc read from nand flash
1223  * @calc_ecc:	ecc read from HW ECC registers
1224  *
1225  * Calculated ecc vector reported as zero in case of non-error pages.
1226  * In case of non-zero ecc vector, first filter out erased-pages, and
1227  * then process data via ELM to detect bit-flips.
1228  */
omap_elm_correct_data(struct nand_chip * chip,u_char * data,u_char * read_ecc,u_char * calc_ecc)1229 static int omap_elm_correct_data(struct nand_chip *chip, u_char *data,
1230 				 u_char *read_ecc, u_char *calc_ecc)
1231 {
1232 	struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip));
1233 	struct nand_ecc_ctrl *ecc = &info->nand.ecc;
1234 	int eccsteps = info->nsteps_per_eccpg;
1235 	int i , j, stat = 0;
1236 	int eccflag, actual_eccbytes;
1237 	struct elm_errorvec err_vec[ERROR_VECTOR_MAX];
1238 	u_char *ecc_vec = calc_ecc;
1239 	u_char *spare_ecc = read_ecc;
1240 	u_char *erased_ecc_vec;
1241 	u_char *buf;
1242 	int bitflip_count;
1243 	bool is_error_reported = false;
1244 	u32 bit_pos, byte_pos, error_max, pos;
1245 	int err;
1246 
1247 	switch (info->ecc_opt) {
1248 	case OMAP_ECC_BCH4_CODE_HW:
1249 		/* omit  7th ECC byte reserved for ROM code compatibility */
1250 		actual_eccbytes = ecc->bytes - 1;
1251 		erased_ecc_vec = bch4_vector;
1252 		break;
1253 	case OMAP_ECC_BCH8_CODE_HW:
1254 		/* omit 14th ECC byte reserved for ROM code compatibility */
1255 		actual_eccbytes = ecc->bytes - 1;
1256 		erased_ecc_vec = bch8_vector;
1257 		break;
1258 	case OMAP_ECC_BCH16_CODE_HW:
1259 		actual_eccbytes = ecc->bytes;
1260 		erased_ecc_vec = bch16_vector;
1261 		break;
1262 	default:
1263 		dev_err(&info->pdev->dev, "invalid driver configuration\n");
1264 		return -EINVAL;
1265 	}
1266 
1267 	/* Initialize elm error vector to zero */
1268 	memset(err_vec, 0, sizeof(err_vec));
1269 
1270 	for (i = 0; i < eccsteps ; i++) {
1271 		eccflag = 0;	/* initialize eccflag */
1272 
1273 		/*
1274 		 * Check any error reported,
1275 		 * In case of error, non zero ecc reported.
1276 		 */
1277 		for (j = 0; j < actual_eccbytes; j++) {
1278 			if (calc_ecc[j] != 0) {
1279 				eccflag = 1; /* non zero ecc, error present */
1280 				break;
1281 			}
1282 		}
1283 
1284 		if (eccflag == 1) {
1285 			if (memcmp(calc_ecc, erased_ecc_vec,
1286 						actual_eccbytes) == 0) {
1287 				/*
1288 				 * calc_ecc[] matches pattern for ECC(all 0xff)
1289 				 * so this is definitely an erased-page
1290 				 */
1291 			} else {
1292 				buf = &data[info->nand.ecc.size * i];
1293 				/*
1294 				 * count number of 0-bits in read_buf.
1295 				 * This check can be removed once a similar
1296 				 * check is introduced in generic NAND driver
1297 				 */
1298 				bitflip_count = erased_sector_bitflips(
1299 						buf, read_ecc, info);
1300 				if (bitflip_count) {
1301 					/*
1302 					 * number of 0-bits within ECC limits
1303 					 * So this may be an erased-page
1304 					 */
1305 					stat += bitflip_count;
1306 				} else {
1307 					/*
1308 					 * Too many 0-bits. It may be a
1309 					 * - programmed-page, OR
1310 					 * - erased-page with many bit-flips
1311 					 * So this page requires check by ELM
1312 					 */
1313 					err_vec[i].error_reported = true;
1314 					is_error_reported = true;
1315 				}
1316 			}
1317 		}
1318 
1319 		/* Update the ecc vector */
1320 		calc_ecc += ecc->bytes;
1321 		read_ecc += ecc->bytes;
1322 	}
1323 
1324 	/* Check if any error reported */
1325 	if (!is_error_reported)
1326 		return stat;
1327 
1328 	/* Decode BCH error using ELM module */
1329 	elm_decode_bch_error_page(info->elm_dev, ecc_vec, err_vec);
1330 
1331 	err = 0;
1332 	for (i = 0; i < eccsteps; i++) {
1333 		if (err_vec[i].error_uncorrectable) {
1334 			dev_err(&info->pdev->dev,
1335 				"uncorrectable bit-flips found\n");
1336 			err = -EBADMSG;
1337 		} else if (err_vec[i].error_reported) {
1338 			for (j = 0; j < err_vec[i].error_count; j++) {
1339 				switch (info->ecc_opt) {
1340 				case OMAP_ECC_BCH4_CODE_HW:
1341 					/* Add 4 bits to take care of padding */
1342 					pos = err_vec[i].error_loc[j] +
1343 						BCH4_BIT_PAD;
1344 					break;
1345 				case OMAP_ECC_BCH8_CODE_HW:
1346 				case OMAP_ECC_BCH16_CODE_HW:
1347 					pos = err_vec[i].error_loc[j];
1348 					break;
1349 				default:
1350 					return -EINVAL;
1351 				}
1352 				error_max = (ecc->size + actual_eccbytes) * 8;
1353 				/* Calculate bit position of error */
1354 				bit_pos = pos % 8;
1355 
1356 				/* Calculate byte position of error */
1357 				byte_pos = (error_max - pos - 1) / 8;
1358 
1359 				if (pos < error_max) {
1360 					if (byte_pos < 512) {
1361 						pr_debug("bitflip@dat[%d]=%x\n",
1362 						     byte_pos, data[byte_pos]);
1363 						data[byte_pos] ^= 1 << bit_pos;
1364 					} else {
1365 						pr_debug("bitflip@oob[%d]=%x\n",
1366 							(byte_pos - 512),
1367 						     spare_ecc[byte_pos - 512]);
1368 						spare_ecc[byte_pos - 512] ^=
1369 							1 << bit_pos;
1370 					}
1371 				} else {
1372 					dev_err(&info->pdev->dev,
1373 						"invalid bit-flip @ %d:%d\n",
1374 						byte_pos, bit_pos);
1375 					err = -EBADMSG;
1376 				}
1377 			}
1378 		}
1379 
1380 		/* Update number of correctable errors */
1381 		stat = max_t(unsigned int, stat, err_vec[i].error_count);
1382 
1383 		/* Update page data with sector size */
1384 		data += ecc->size;
1385 		spare_ecc += ecc->bytes;
1386 	}
1387 
1388 	return (err) ? err : stat;
1389 }
1390 
1391 /**
1392  * omap_write_page_bch - BCH ecc based write page function for entire page
1393  * @chip:		nand chip info structure
1394  * @buf:		data buffer
1395  * @oob_required:	must write chip->oob_poi to OOB
1396  * @page:		page
1397  *
1398  * Custom write page method evolved to support multi sector writing in one shot
1399  */
omap_write_page_bch(struct nand_chip * chip,const uint8_t * buf,int oob_required,int page)1400 static int omap_write_page_bch(struct nand_chip *chip, const uint8_t *buf,
1401 			       int oob_required, int page)
1402 {
1403 	struct mtd_info *mtd = nand_to_mtd(chip);
1404 	struct omap_nand_info *info = mtd_to_omap(mtd);
1405 	uint8_t *ecc_calc = chip->ecc.calc_buf;
1406 	unsigned int eccpg;
1407 	int ret;
1408 
1409 	ret = nand_prog_page_begin_op(chip, page, 0, NULL, 0);
1410 	if (ret)
1411 		return ret;
1412 
1413 	for (eccpg = 0; eccpg < info->neccpg; eccpg++) {
1414 		/* Enable GPMC ecc engine */
1415 		chip->ecc.hwctl(chip, NAND_ECC_WRITE);
1416 
1417 		/* Write data */
1418 		info->data_out(chip, buf + (eccpg * info->eccpg_size),
1419 			       info->eccpg_size, false);
1420 
1421 		/* Update ecc vector from GPMC result registers */
1422 		ret = omap_calculate_ecc_bch_multi(mtd,
1423 						   buf + (eccpg * info->eccpg_size),
1424 						   ecc_calc);
1425 		if (ret)
1426 			return ret;
1427 
1428 		ret = mtd_ooblayout_set_eccbytes(mtd, ecc_calc,
1429 						 chip->oob_poi,
1430 						 eccpg * info->eccpg_bytes,
1431 						 info->eccpg_bytes);
1432 		if (ret)
1433 			return ret;
1434 	}
1435 
1436 	/* Write ecc vector to OOB area */
1437 	info->data_out(chip, chip->oob_poi, mtd->oobsize, false);
1438 
1439 	return nand_prog_page_end_op(chip);
1440 }
1441 
1442 /**
1443  * omap_write_subpage_bch - BCH hardware ECC based subpage write
1444  * @chip:	nand chip info structure
1445  * @offset:	column address of subpage within the page
1446  * @data_len:	data length
1447  * @buf:	data buffer
1448  * @oob_required: must write chip->oob_poi to OOB
1449  * @page: page number to write
1450  *
1451  * OMAP optimized subpage write method.
1452  */
omap_write_subpage_bch(struct nand_chip * chip,u32 offset,u32 data_len,const u8 * buf,int oob_required,int page)1453 static int omap_write_subpage_bch(struct nand_chip *chip, u32 offset,
1454 				  u32 data_len, const u8 *buf,
1455 				  int oob_required, int page)
1456 {
1457 	struct mtd_info *mtd = nand_to_mtd(chip);
1458 	struct omap_nand_info *info = mtd_to_omap(mtd);
1459 	u8 *ecc_calc = chip->ecc.calc_buf;
1460 	int ecc_size      = chip->ecc.size;
1461 	int ecc_bytes     = chip->ecc.bytes;
1462 	u32 start_step = offset / ecc_size;
1463 	u32 end_step   = (offset + data_len - 1) / ecc_size;
1464 	unsigned int eccpg;
1465 	int step, ret = 0;
1466 
1467 	/*
1468 	 * Write entire page at one go as it would be optimal
1469 	 * as ECC is calculated by hardware.
1470 	 * ECC is calculated for all subpages but we choose
1471 	 * only what we want.
1472 	 */
1473 	ret = nand_prog_page_begin_op(chip, page, 0, NULL, 0);
1474 	if (ret)
1475 		return ret;
1476 
1477 	for (eccpg = 0; eccpg < info->neccpg; eccpg++) {
1478 		/* Enable GPMC ECC engine */
1479 		chip->ecc.hwctl(chip, NAND_ECC_WRITE);
1480 
1481 		/* Write data */
1482 		info->data_out(chip, buf + (eccpg * info->eccpg_size),
1483 			       info->eccpg_size, false);
1484 
1485 		for (step = 0; step < info->nsteps_per_eccpg; step++) {
1486 			unsigned int base_step = eccpg * info->nsteps_per_eccpg;
1487 			const u8 *bufoffs = buf + (eccpg * info->eccpg_size);
1488 
1489 			/* Mask ECC of un-touched subpages with 0xFFs */
1490 			if ((step + base_step) < start_step ||
1491 			    (step + base_step) > end_step)
1492 				memset(ecc_calc + (step * ecc_bytes), 0xff,
1493 				       ecc_bytes);
1494 			else
1495 				ret = _omap_calculate_ecc_bch(mtd,
1496 							      bufoffs + (step * ecc_size),
1497 							      ecc_calc + (step * ecc_bytes),
1498 							      step);
1499 
1500 			if (ret)
1501 				return ret;
1502 		}
1503 
1504 		/*
1505 		 * Copy the calculated ECC for the whole page including the
1506 		 * masked values (0xFF) corresponding to unwritten subpages.
1507 		 */
1508 		ret = mtd_ooblayout_set_eccbytes(mtd, ecc_calc, chip->oob_poi,
1509 						 eccpg * info->eccpg_bytes,
1510 						 info->eccpg_bytes);
1511 		if (ret)
1512 			return ret;
1513 	}
1514 
1515 	/* write OOB buffer to NAND device */
1516 	info->data_out(chip, chip->oob_poi, mtd->oobsize, false);
1517 
1518 	return nand_prog_page_end_op(chip);
1519 }
1520 
1521 /**
1522  * omap_read_page_bch - BCH ecc based page read function for entire page
1523  * @chip:		nand chip info structure
1524  * @buf:		buffer to store read data
1525  * @oob_required:	caller requires OOB data read to chip->oob_poi
1526  * @page:		page number to read
1527  *
1528  * For BCH ecc scheme, GPMC used for syndrome calculation and ELM module
1529  * used for error correction.
1530  * Custom method evolved to support ELM error correction & multi sector
1531  * reading. On reading page data area is read along with OOB data with
1532  * ecc engine enabled. ecc vector updated after read of OOB data.
1533  * For non error pages ecc vector reported as zero.
1534  */
omap_read_page_bch(struct nand_chip * chip,uint8_t * buf,int oob_required,int page)1535 static int omap_read_page_bch(struct nand_chip *chip, uint8_t *buf,
1536 			      int oob_required, int page)
1537 {
1538 	struct mtd_info *mtd = nand_to_mtd(chip);
1539 	struct omap_nand_info *info = mtd_to_omap(mtd);
1540 	uint8_t *ecc_calc = chip->ecc.calc_buf;
1541 	uint8_t *ecc_code = chip->ecc.code_buf;
1542 	unsigned int max_bitflips = 0, eccpg;
1543 	int stat, ret;
1544 
1545 	ret = nand_read_page_op(chip, page, 0, NULL, 0);
1546 	if (ret)
1547 		return ret;
1548 
1549 	for (eccpg = 0; eccpg < info->neccpg; eccpg++) {
1550 		/* Enable GPMC ecc engine */
1551 		chip->ecc.hwctl(chip, NAND_ECC_READ);
1552 
1553 		/* Read data */
1554 		ret = nand_change_read_column_op(chip, eccpg * info->eccpg_size,
1555 						 buf + (eccpg * info->eccpg_size),
1556 						 info->eccpg_size, false);
1557 		if (ret)
1558 			return ret;
1559 
1560 		/* Read oob bytes */
1561 		ret = nand_change_read_column_op(chip,
1562 						 mtd->writesize + BBM_LEN +
1563 						 (eccpg * info->eccpg_bytes),
1564 						 chip->oob_poi + BBM_LEN +
1565 						 (eccpg * info->eccpg_bytes),
1566 						 info->eccpg_bytes, false);
1567 		if (ret)
1568 			return ret;
1569 
1570 		/* Calculate ecc bytes */
1571 		ret = omap_calculate_ecc_bch_multi(mtd,
1572 						   buf + (eccpg * info->eccpg_size),
1573 						   ecc_calc);
1574 		if (ret)
1575 			return ret;
1576 
1577 		ret = mtd_ooblayout_get_eccbytes(mtd, ecc_code,
1578 						 chip->oob_poi,
1579 						 eccpg * info->eccpg_bytes,
1580 						 info->eccpg_bytes);
1581 		if (ret)
1582 			return ret;
1583 
1584 		stat = chip->ecc.correct(chip,
1585 					 buf + (eccpg * info->eccpg_size),
1586 					 ecc_code, ecc_calc);
1587 		if (stat < 0) {
1588 			mtd->ecc_stats.failed++;
1589 		} else {
1590 			mtd->ecc_stats.corrected += stat;
1591 			max_bitflips = max_t(unsigned int, max_bitflips, stat);
1592 		}
1593 	}
1594 
1595 	return max_bitflips;
1596 }
1597 
1598 /**
1599  * is_elm_present - checks for presence of ELM module by scanning DT nodes
1600  * @info: NAND device structure containing platform data
1601  * @elm_node: ELM's DT node
1602  */
is_elm_present(struct omap_nand_info * info,struct device_node * elm_node)1603 static bool is_elm_present(struct omap_nand_info *info,
1604 			   struct device_node *elm_node)
1605 {
1606 	struct platform_device *pdev;
1607 
1608 	/* check whether elm-id is passed via DT */
1609 	if (!elm_node) {
1610 		dev_err(&info->pdev->dev, "ELM devicetree node not found\n");
1611 		return false;
1612 	}
1613 	pdev = of_find_device_by_node(elm_node);
1614 	/* check whether ELM device is registered */
1615 	if (!pdev) {
1616 		dev_err(&info->pdev->dev, "ELM device not found\n");
1617 		return false;
1618 	}
1619 	/* ELM module available, now configure it */
1620 	info->elm_dev = &pdev->dev;
1621 	return true;
1622 }
1623 
omap2_nand_ecc_check(struct omap_nand_info * info)1624 static bool omap2_nand_ecc_check(struct omap_nand_info *info)
1625 {
1626 	bool ecc_needs_bch, ecc_needs_omap_bch, ecc_needs_elm;
1627 
1628 	switch (info->ecc_opt) {
1629 	case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW:
1630 	case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
1631 		ecc_needs_omap_bch = false;
1632 		ecc_needs_bch = true;
1633 		ecc_needs_elm = false;
1634 		break;
1635 	case OMAP_ECC_BCH4_CODE_HW:
1636 	case OMAP_ECC_BCH8_CODE_HW:
1637 	case OMAP_ECC_BCH16_CODE_HW:
1638 		ecc_needs_omap_bch = true;
1639 		ecc_needs_bch = false;
1640 		ecc_needs_elm = true;
1641 		break;
1642 	default:
1643 		ecc_needs_omap_bch = false;
1644 		ecc_needs_bch = false;
1645 		ecc_needs_elm = false;
1646 		break;
1647 	}
1648 
1649 	if (ecc_needs_bch && !IS_ENABLED(CONFIG_MTD_NAND_ECC_SW_BCH)) {
1650 		dev_err(&info->pdev->dev,
1651 			"CONFIG_MTD_NAND_ECC_SW_BCH not enabled\n");
1652 		return false;
1653 	}
1654 	if (ecc_needs_omap_bch && !IS_ENABLED(CONFIG_MTD_NAND_OMAP_BCH)) {
1655 		dev_err(&info->pdev->dev,
1656 			"CONFIG_MTD_NAND_OMAP_BCH not enabled\n");
1657 		return false;
1658 	}
1659 	if (ecc_needs_elm && !is_elm_present(info, info->elm_of_node)) {
1660 		dev_err(&info->pdev->dev, "ELM not available\n");
1661 		return false;
1662 	}
1663 
1664 	return true;
1665 }
1666 
1667 static const char * const nand_xfer_types[] = {
1668 	[NAND_OMAP_PREFETCH_POLLED] = "prefetch-polled",
1669 	[NAND_OMAP_POLLED] = "polled",
1670 	[NAND_OMAP_PREFETCH_DMA] = "prefetch-dma",
1671 	[NAND_OMAP_PREFETCH_IRQ] = "prefetch-irq",
1672 };
1673 
omap_get_dt_info(struct device * dev,struct omap_nand_info * info)1674 static int omap_get_dt_info(struct device *dev, struct omap_nand_info *info)
1675 {
1676 	struct device_node *child = dev->of_node;
1677 	int i;
1678 	const char *s;
1679 	u32 cs;
1680 
1681 	if (of_property_read_u32(child, "reg", &cs) < 0) {
1682 		dev_err(dev, "reg not found in DT\n");
1683 		return -EINVAL;
1684 	}
1685 
1686 	info->gpmc_cs = cs;
1687 
1688 	/* detect availability of ELM module. Won't be present pre-OMAP4 */
1689 	info->elm_of_node = of_parse_phandle(child, "ti,elm-id", 0);
1690 	if (!info->elm_of_node) {
1691 		info->elm_of_node = of_parse_phandle(child, "elm_id", 0);
1692 		if (!info->elm_of_node)
1693 			dev_dbg(dev, "ti,elm-id not in DT\n");
1694 	}
1695 
1696 	/* select ecc-scheme for NAND */
1697 	if (of_property_read_string(child, "ti,nand-ecc-opt", &s)) {
1698 		dev_err(dev, "ti,nand-ecc-opt not found\n");
1699 		return -EINVAL;
1700 	}
1701 
1702 	if (!strcmp(s, "sw")) {
1703 		info->ecc_opt = OMAP_ECC_HAM1_CODE_SW;
1704 	} else if (!strcmp(s, "ham1") ||
1705 		   !strcmp(s, "hw") || !strcmp(s, "hw-romcode")) {
1706 		info->ecc_opt =	OMAP_ECC_HAM1_CODE_HW;
1707 	} else if (!strcmp(s, "bch4")) {
1708 		if (info->elm_of_node)
1709 			info->ecc_opt = OMAP_ECC_BCH4_CODE_HW;
1710 		else
1711 			info->ecc_opt = OMAP_ECC_BCH4_CODE_HW_DETECTION_SW;
1712 	} else if (!strcmp(s, "bch8")) {
1713 		if (info->elm_of_node)
1714 			info->ecc_opt = OMAP_ECC_BCH8_CODE_HW;
1715 		else
1716 			info->ecc_opt = OMAP_ECC_BCH8_CODE_HW_DETECTION_SW;
1717 	} else if (!strcmp(s, "bch16")) {
1718 		info->ecc_opt =	OMAP_ECC_BCH16_CODE_HW;
1719 	} else {
1720 		dev_err(dev, "unrecognized value for ti,nand-ecc-opt\n");
1721 		return -EINVAL;
1722 	}
1723 
1724 	/* select data transfer mode */
1725 	if (!of_property_read_string(child, "ti,nand-xfer-type", &s)) {
1726 		for (i = 0; i < ARRAY_SIZE(nand_xfer_types); i++) {
1727 			if (!strcasecmp(s, nand_xfer_types[i])) {
1728 				info->xfer_type = i;
1729 				return 0;
1730 			}
1731 		}
1732 
1733 		dev_err(dev, "unrecognized value for ti,nand-xfer-type\n");
1734 		return -EINVAL;
1735 	}
1736 
1737 	return 0;
1738 }
1739 
omap_ooblayout_ecc(struct mtd_info * mtd,int section,struct mtd_oob_region * oobregion)1740 static int omap_ooblayout_ecc(struct mtd_info *mtd, int section,
1741 			      struct mtd_oob_region *oobregion)
1742 {
1743 	struct omap_nand_info *info = mtd_to_omap(mtd);
1744 	struct nand_chip *chip = &info->nand;
1745 	int off = BBM_LEN;
1746 
1747 	if (info->ecc_opt == OMAP_ECC_HAM1_CODE_HW &&
1748 	    !(chip->options & NAND_BUSWIDTH_16))
1749 		off = 1;
1750 
1751 	if (section)
1752 		return -ERANGE;
1753 
1754 	oobregion->offset = off;
1755 	oobregion->length = chip->ecc.total;
1756 
1757 	return 0;
1758 }
1759 
omap_ooblayout_free(struct mtd_info * mtd,int section,struct mtd_oob_region * oobregion)1760 static int omap_ooblayout_free(struct mtd_info *mtd, int section,
1761 			       struct mtd_oob_region *oobregion)
1762 {
1763 	struct omap_nand_info *info = mtd_to_omap(mtd);
1764 	struct nand_chip *chip = &info->nand;
1765 	int off = BBM_LEN;
1766 
1767 	if (info->ecc_opt == OMAP_ECC_HAM1_CODE_HW &&
1768 	    !(chip->options & NAND_BUSWIDTH_16))
1769 		off = 1;
1770 
1771 	if (section)
1772 		return -ERANGE;
1773 
1774 	off += chip->ecc.total;
1775 	if (off >= mtd->oobsize)
1776 		return -ERANGE;
1777 
1778 	oobregion->offset = off;
1779 	oobregion->length = mtd->oobsize - off;
1780 
1781 	return 0;
1782 }
1783 
1784 static const struct mtd_ooblayout_ops omap_ooblayout_ops = {
1785 	.ecc = omap_ooblayout_ecc,
1786 	.free = omap_ooblayout_free,
1787 };
1788 
omap_sw_ooblayout_ecc(struct mtd_info * mtd,int section,struct mtd_oob_region * oobregion)1789 static int omap_sw_ooblayout_ecc(struct mtd_info *mtd, int section,
1790 				 struct mtd_oob_region *oobregion)
1791 {
1792 	struct nand_device *nand = mtd_to_nanddev(mtd);
1793 	unsigned int nsteps = nanddev_get_ecc_nsteps(nand);
1794 	unsigned int ecc_bytes = nanddev_get_ecc_bytes_per_step(nand);
1795 	int off = BBM_LEN;
1796 
1797 	if (section >= nsteps)
1798 		return -ERANGE;
1799 
1800 	/*
1801 	 * When SW correction is employed, one OMAP specific marker byte is
1802 	 * reserved after each ECC step.
1803 	 */
1804 	oobregion->offset = off + (section * (ecc_bytes + 1));
1805 	oobregion->length = ecc_bytes;
1806 
1807 	return 0;
1808 }
1809 
omap_sw_ooblayout_free(struct mtd_info * mtd,int section,struct mtd_oob_region * oobregion)1810 static int omap_sw_ooblayout_free(struct mtd_info *mtd, int section,
1811 				  struct mtd_oob_region *oobregion)
1812 {
1813 	struct nand_device *nand = mtd_to_nanddev(mtd);
1814 	unsigned int nsteps = nanddev_get_ecc_nsteps(nand);
1815 	unsigned int ecc_bytes = nanddev_get_ecc_bytes_per_step(nand);
1816 	int off = BBM_LEN;
1817 
1818 	if (section)
1819 		return -ERANGE;
1820 
1821 	/*
1822 	 * When SW correction is employed, one OMAP specific marker byte is
1823 	 * reserved after each ECC step.
1824 	 */
1825 	off += ((ecc_bytes + 1) * nsteps);
1826 	if (off >= mtd->oobsize)
1827 		return -ERANGE;
1828 
1829 	oobregion->offset = off;
1830 	oobregion->length = mtd->oobsize - off;
1831 
1832 	return 0;
1833 }
1834 
1835 static const struct mtd_ooblayout_ops omap_sw_ooblayout_ops = {
1836 	.ecc = omap_sw_ooblayout_ecc,
1837 	.free = omap_sw_ooblayout_free,
1838 };
1839 
omap_nand_attach_chip(struct nand_chip * chip)1840 static int omap_nand_attach_chip(struct nand_chip *chip)
1841 {
1842 	struct mtd_info *mtd = nand_to_mtd(chip);
1843 	struct omap_nand_info *info = mtd_to_omap(mtd);
1844 	struct device *dev = &info->pdev->dev;
1845 	int min_oobbytes = BBM_LEN;
1846 	int elm_bch_strength = -1;
1847 	int oobbytes_per_step;
1848 	dma_cap_mask_t mask;
1849 	int err;
1850 
1851 	if (chip->bbt_options & NAND_BBT_USE_FLASH)
1852 		chip->bbt_options |= NAND_BBT_NO_OOB;
1853 	else
1854 		chip->options |= NAND_SKIP_BBTSCAN;
1855 
1856 	/* Re-populate low-level callbacks based on xfer modes */
1857 	switch (info->xfer_type) {
1858 	case NAND_OMAP_PREFETCH_POLLED:
1859 		info->data_in = omap_nand_data_in_pref;
1860 		info->data_out = omap_nand_data_out_pref;
1861 		break;
1862 
1863 	case NAND_OMAP_POLLED:
1864 		/* Use nand_base defaults for {read,write}_buf */
1865 		break;
1866 
1867 	case NAND_OMAP_PREFETCH_DMA:
1868 		dma_cap_zero(mask);
1869 		dma_cap_set(DMA_SLAVE, mask);
1870 		info->dma = dma_request_chan(dev->parent, "rxtx");
1871 
1872 		if (IS_ERR(info->dma)) {
1873 			dev_err(dev, "DMA engine request failed\n");
1874 			return PTR_ERR(info->dma);
1875 		} else {
1876 			struct dma_slave_config cfg;
1877 
1878 			memset(&cfg, 0, sizeof(cfg));
1879 			cfg.src_addr = info->phys_base;
1880 			cfg.dst_addr = info->phys_base;
1881 			cfg.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1882 			cfg.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
1883 			cfg.src_maxburst = 16;
1884 			cfg.dst_maxburst = 16;
1885 			err = dmaengine_slave_config(info->dma, &cfg);
1886 			if (err) {
1887 				dev_err(dev,
1888 					"DMA engine slave config failed: %d\n",
1889 					err);
1890 				return err;
1891 			}
1892 
1893 			info->data_in = omap_nand_data_in_dma_pref;
1894 			info->data_out = omap_nand_data_out_dma_pref;
1895 		}
1896 		break;
1897 
1898 	case NAND_OMAP_PREFETCH_IRQ:
1899 		info->gpmc_irq_fifo = platform_get_irq(info->pdev, 0);
1900 		if (info->gpmc_irq_fifo < 0)
1901 			return info->gpmc_irq_fifo;
1902 		err = devm_request_irq(dev, info->gpmc_irq_fifo,
1903 				       omap_nand_irq, IRQF_SHARED,
1904 				       "gpmc-nand-fifo", info);
1905 		if (err) {
1906 			dev_err(dev, "Requesting IRQ %d, error %d\n",
1907 				info->gpmc_irq_fifo, err);
1908 			info->gpmc_irq_fifo = 0;
1909 			return err;
1910 		}
1911 
1912 		info->gpmc_irq_count = platform_get_irq(info->pdev, 1);
1913 		if (info->gpmc_irq_count < 0)
1914 			return info->gpmc_irq_count;
1915 		err = devm_request_irq(dev, info->gpmc_irq_count,
1916 				       omap_nand_irq, IRQF_SHARED,
1917 				       "gpmc-nand-count", info);
1918 		if (err) {
1919 			dev_err(dev, "Requesting IRQ %d, error %d\n",
1920 				info->gpmc_irq_count, err);
1921 			info->gpmc_irq_count = 0;
1922 			return err;
1923 		}
1924 
1925 		info->data_in = omap_nand_data_in_irq_pref;
1926 		info->data_out = omap_nand_data_out_irq_pref;
1927 		break;
1928 
1929 	default:
1930 		dev_err(dev, "xfer_type %d not supported!\n", info->xfer_type);
1931 		return -EINVAL;
1932 	}
1933 
1934 	if (!omap2_nand_ecc_check(info))
1935 		return -EINVAL;
1936 
1937 	/*
1938 	 * Bail out earlier to let NAND_ECC_ENGINE_TYPE_SOFT code create its own
1939 	 * ooblayout instead of using ours.
1940 	 */
1941 	if (info->ecc_opt == OMAP_ECC_HAM1_CODE_SW) {
1942 		chip->ecc.engine_type = NAND_ECC_ENGINE_TYPE_SOFT;
1943 		chip->ecc.algo = NAND_ECC_ALGO_HAMMING;
1944 		return 0;
1945 	}
1946 
1947 	/* Populate MTD interface based on ECC scheme */
1948 	switch (info->ecc_opt) {
1949 	case OMAP_ECC_HAM1_CODE_HW:
1950 		dev_info(dev, "nand: using OMAP_ECC_HAM1_CODE_HW\n");
1951 		chip->ecc.engine_type	= NAND_ECC_ENGINE_TYPE_ON_HOST;
1952 		chip->ecc.bytes		= 3;
1953 		chip->ecc.size		= 512;
1954 		chip->ecc.strength	= 1;
1955 		chip->ecc.calculate	= omap_calculate_ecc;
1956 		chip->ecc.hwctl		= omap_enable_hwecc;
1957 		chip->ecc.correct	= omap_correct_data;
1958 		mtd_set_ooblayout(mtd, &omap_ooblayout_ops);
1959 		oobbytes_per_step	= chip->ecc.bytes;
1960 
1961 		if (!(chip->options & NAND_BUSWIDTH_16))
1962 			min_oobbytes	= 1;
1963 
1964 		break;
1965 
1966 	case OMAP_ECC_BCH4_CODE_HW_DETECTION_SW:
1967 		pr_info("nand: using OMAP_ECC_BCH4_CODE_HW_DETECTION_SW\n");
1968 		chip->ecc.engine_type	= NAND_ECC_ENGINE_TYPE_ON_HOST;
1969 		chip->ecc.size		= 512;
1970 		chip->ecc.bytes		= 7;
1971 		chip->ecc.strength	= 4;
1972 		chip->ecc.hwctl		= omap_enable_hwecc_bch;
1973 		chip->ecc.correct	= rawnand_sw_bch_correct;
1974 		chip->ecc.calculate	= omap_calculate_ecc_bch_sw;
1975 		mtd_set_ooblayout(mtd, &omap_sw_ooblayout_ops);
1976 		/* Reserve one byte for the OMAP marker */
1977 		oobbytes_per_step	= chip->ecc.bytes + 1;
1978 		/* Software BCH library is used for locating errors */
1979 		err = rawnand_sw_bch_init(chip);
1980 		if (err) {
1981 			dev_err(dev, "Unable to use BCH library\n");
1982 			return err;
1983 		}
1984 		break;
1985 
1986 	case OMAP_ECC_BCH4_CODE_HW:
1987 		pr_info("nand: using OMAP_ECC_BCH4_CODE_HW ECC scheme\n");
1988 		chip->ecc.engine_type	= NAND_ECC_ENGINE_TYPE_ON_HOST;
1989 		chip->ecc.size		= 512;
1990 		/* 14th bit is kept reserved for ROM-code compatibility */
1991 		chip->ecc.bytes		= 7 + 1;
1992 		chip->ecc.strength	= 4;
1993 		chip->ecc.hwctl		= omap_enable_hwecc_bch;
1994 		chip->ecc.correct	= omap_elm_correct_data;
1995 		chip->ecc.read_page	= omap_read_page_bch;
1996 		chip->ecc.write_page	= omap_write_page_bch;
1997 		chip->ecc.write_subpage	= omap_write_subpage_bch;
1998 		mtd_set_ooblayout(mtd, &omap_ooblayout_ops);
1999 		oobbytes_per_step	= chip->ecc.bytes;
2000 		elm_bch_strength = BCH4_ECC;
2001 		break;
2002 
2003 	case OMAP_ECC_BCH8_CODE_HW_DETECTION_SW:
2004 		pr_info("nand: using OMAP_ECC_BCH8_CODE_HW_DETECTION_SW\n");
2005 		chip->ecc.engine_type	= NAND_ECC_ENGINE_TYPE_ON_HOST;
2006 		chip->ecc.size		= 512;
2007 		chip->ecc.bytes		= 13;
2008 		chip->ecc.strength	= 8;
2009 		chip->ecc.hwctl		= omap_enable_hwecc_bch;
2010 		chip->ecc.correct	= rawnand_sw_bch_correct;
2011 		chip->ecc.calculate	= omap_calculate_ecc_bch_sw;
2012 		mtd_set_ooblayout(mtd, &omap_sw_ooblayout_ops);
2013 		/* Reserve one byte for the OMAP marker */
2014 		oobbytes_per_step	= chip->ecc.bytes + 1;
2015 		/* Software BCH library is used for locating errors */
2016 		err = rawnand_sw_bch_init(chip);
2017 		if (err) {
2018 			dev_err(dev, "unable to use BCH library\n");
2019 			return err;
2020 		}
2021 		break;
2022 
2023 	case OMAP_ECC_BCH8_CODE_HW:
2024 		pr_info("nand: using OMAP_ECC_BCH8_CODE_HW ECC scheme\n");
2025 		chip->ecc.engine_type	= NAND_ECC_ENGINE_TYPE_ON_HOST;
2026 		chip->ecc.size		= 512;
2027 		/* 14th bit is kept reserved for ROM-code compatibility */
2028 		chip->ecc.bytes		= 13 + 1;
2029 		chip->ecc.strength	= 8;
2030 		chip->ecc.hwctl		= omap_enable_hwecc_bch;
2031 		chip->ecc.correct	= omap_elm_correct_data;
2032 		chip->ecc.read_page	= omap_read_page_bch;
2033 		chip->ecc.write_page	= omap_write_page_bch;
2034 		chip->ecc.write_subpage	= omap_write_subpage_bch;
2035 		mtd_set_ooblayout(mtd, &omap_ooblayout_ops);
2036 		oobbytes_per_step	= chip->ecc.bytes;
2037 		elm_bch_strength = BCH8_ECC;
2038 		break;
2039 
2040 	case OMAP_ECC_BCH16_CODE_HW:
2041 		pr_info("Using OMAP_ECC_BCH16_CODE_HW ECC scheme\n");
2042 		chip->ecc.engine_type	= NAND_ECC_ENGINE_TYPE_ON_HOST;
2043 		chip->ecc.size		= 512;
2044 		chip->ecc.bytes		= 26;
2045 		chip->ecc.strength	= 16;
2046 		chip->ecc.hwctl		= omap_enable_hwecc_bch;
2047 		chip->ecc.correct	= omap_elm_correct_data;
2048 		chip->ecc.read_page	= omap_read_page_bch;
2049 		chip->ecc.write_page	= omap_write_page_bch;
2050 		chip->ecc.write_subpage	= omap_write_subpage_bch;
2051 		mtd_set_ooblayout(mtd, &omap_ooblayout_ops);
2052 		oobbytes_per_step	= chip->ecc.bytes;
2053 		elm_bch_strength = BCH16_ECC;
2054 		break;
2055 	default:
2056 		dev_err(dev, "Invalid or unsupported ECC scheme\n");
2057 		return -EINVAL;
2058 	}
2059 
2060 	if (elm_bch_strength >= 0) {
2061 		chip->ecc.steps = mtd->writesize / chip->ecc.size;
2062 		info->neccpg = chip->ecc.steps / ERROR_VECTOR_MAX;
2063 		if (info->neccpg) {
2064 			info->nsteps_per_eccpg = ERROR_VECTOR_MAX;
2065 		} else {
2066 			info->neccpg = 1;
2067 			info->nsteps_per_eccpg = chip->ecc.steps;
2068 		}
2069 		info->eccpg_size = info->nsteps_per_eccpg * chip->ecc.size;
2070 		info->eccpg_bytes = info->nsteps_per_eccpg * chip->ecc.bytes;
2071 
2072 		err = elm_config(info->elm_dev, elm_bch_strength,
2073 				 info->nsteps_per_eccpg, chip->ecc.size,
2074 				 chip->ecc.bytes);
2075 		if (err < 0)
2076 			return err;
2077 	}
2078 
2079 	/* Check if NAND device's OOB is enough to store ECC signatures */
2080 	min_oobbytes += (oobbytes_per_step *
2081 			 (mtd->writesize / chip->ecc.size));
2082 	if (mtd->oobsize < min_oobbytes) {
2083 		dev_err(dev,
2084 			"Not enough OOB bytes: required = %d, available=%d\n",
2085 			min_oobbytes, mtd->oobsize);
2086 		return -EINVAL;
2087 	}
2088 
2089 	return 0;
2090 }
2091 
omap_nand_data_in(struct nand_chip * chip,void * buf,unsigned int len,bool force_8bit)2092 static void omap_nand_data_in(struct nand_chip *chip, void *buf,
2093 			      unsigned int len, bool force_8bit)
2094 {
2095 	struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip));
2096 	u32 alignment = ((uintptr_t)buf | len) & 3;
2097 
2098 	if (force_8bit || (alignment & 1))
2099 		ioread8_rep(info->fifo, buf, len);
2100 	else if (alignment & 3)
2101 		ioread16_rep(info->fifo, buf, len >> 1);
2102 	else
2103 		ioread32_rep(info->fifo, buf, len >> 2);
2104 }
2105 
omap_nand_data_out(struct nand_chip * chip,const void * buf,unsigned int len,bool force_8bit)2106 static void omap_nand_data_out(struct nand_chip *chip,
2107 			       const void *buf, unsigned int len,
2108 			       bool force_8bit)
2109 {
2110 	struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip));
2111 	u32 alignment = ((uintptr_t)buf | len) & 3;
2112 
2113 	if (force_8bit || (alignment & 1))
2114 		iowrite8_rep(info->fifo, buf, len);
2115 	else if (alignment & 3)
2116 		iowrite16_rep(info->fifo, buf, len >> 1);
2117 	else
2118 		iowrite32_rep(info->fifo, buf, len >> 2);
2119 }
2120 
omap_nand_exec_instr(struct nand_chip * chip,const struct nand_op_instr * instr)2121 static int omap_nand_exec_instr(struct nand_chip *chip,
2122 				const struct nand_op_instr *instr)
2123 {
2124 	struct omap_nand_info *info = mtd_to_omap(nand_to_mtd(chip));
2125 	unsigned int i;
2126 	int ret;
2127 
2128 	switch (instr->type) {
2129 	case NAND_OP_CMD_INSTR:
2130 		iowrite8(instr->ctx.cmd.opcode,
2131 			 info->reg.gpmc_nand_command);
2132 		break;
2133 
2134 	case NAND_OP_ADDR_INSTR:
2135 		for (i = 0; i < instr->ctx.addr.naddrs; i++) {
2136 			iowrite8(instr->ctx.addr.addrs[i],
2137 				 info->reg.gpmc_nand_address);
2138 		}
2139 		break;
2140 
2141 	case NAND_OP_DATA_IN_INSTR:
2142 		info->data_in(chip, instr->ctx.data.buf.in,
2143 			      instr->ctx.data.len,
2144 			      instr->ctx.data.force_8bit);
2145 		break;
2146 
2147 	case NAND_OP_DATA_OUT_INSTR:
2148 		info->data_out(chip, instr->ctx.data.buf.out,
2149 			       instr->ctx.data.len,
2150 			       instr->ctx.data.force_8bit);
2151 		break;
2152 
2153 	case NAND_OP_WAITRDY_INSTR:
2154 		ret = info->ready_gpiod ?
2155 			nand_gpio_waitrdy(chip, info->ready_gpiod, instr->ctx.waitrdy.timeout_ms) :
2156 			nand_soft_waitrdy(chip, instr->ctx.waitrdy.timeout_ms);
2157 		if (ret)
2158 			return ret;
2159 		break;
2160 	}
2161 
2162 	if (instr->delay_ns)
2163 		ndelay(instr->delay_ns);
2164 
2165 	return 0;
2166 }
2167 
omap_nand_exec_op(struct nand_chip * chip,const struct nand_operation * op,bool check_only)2168 static int omap_nand_exec_op(struct nand_chip *chip,
2169 			     const struct nand_operation *op,
2170 			     bool check_only)
2171 {
2172 	unsigned int i;
2173 
2174 	if (check_only)
2175 		return 0;
2176 
2177 	for (i = 0; i < op->ninstrs; i++) {
2178 		int ret;
2179 
2180 		ret = omap_nand_exec_instr(chip, &op->instrs[i]);
2181 		if (ret)
2182 			return ret;
2183 	}
2184 
2185 	return 0;
2186 }
2187 
2188 static const struct nand_controller_ops omap_nand_controller_ops = {
2189 	.attach_chip = omap_nand_attach_chip,
2190 	.exec_op = omap_nand_exec_op,
2191 };
2192 
2193 /* Shared among all NAND instances to synchronize access to the ECC Engine */
2194 static struct nand_controller omap_gpmc_controller;
2195 static bool omap_gpmc_controller_initialized;
2196 
omap_nand_probe(struct platform_device * pdev)2197 static int omap_nand_probe(struct platform_device *pdev)
2198 {
2199 	struct omap_nand_info		*info;
2200 	struct mtd_info			*mtd;
2201 	struct nand_chip		*nand_chip;
2202 	int				err;
2203 	struct resource			*res;
2204 	struct device			*dev = &pdev->dev;
2205 	void __iomem *vaddr;
2206 
2207 	info = devm_kzalloc(&pdev->dev, sizeof(struct omap_nand_info),
2208 				GFP_KERNEL);
2209 	if (!info)
2210 		return -ENOMEM;
2211 
2212 	info->pdev = pdev;
2213 
2214 	err = omap_get_dt_info(dev, info);
2215 	if (err)
2216 		return err;
2217 
2218 	info->ops = gpmc_omap_get_nand_ops(&info->reg, info->gpmc_cs);
2219 	if (!info->ops) {
2220 		dev_err(&pdev->dev, "Failed to get GPMC->NAND interface\n");
2221 		return -ENODEV;
2222 	}
2223 
2224 	nand_chip		= &info->nand;
2225 	mtd			= nand_to_mtd(nand_chip);
2226 	mtd->dev.parent		= &pdev->dev;
2227 	nand_set_flash_node(nand_chip, dev->of_node);
2228 
2229 	if (!mtd->name) {
2230 		mtd->name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
2231 					   "omap2-nand.%d", info->gpmc_cs);
2232 		if (!mtd->name) {
2233 			dev_err(&pdev->dev, "Failed to set MTD name\n");
2234 			return -ENOMEM;
2235 		}
2236 	}
2237 
2238 	vaddr = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
2239 	if (IS_ERR(vaddr))
2240 		return PTR_ERR(vaddr);
2241 
2242 	info->fifo = vaddr;
2243 	info->phys_base = res->start;
2244 
2245 	if (!omap_gpmc_controller_initialized) {
2246 		omap_gpmc_controller.ops = &omap_nand_controller_ops;
2247 		nand_controller_init(&omap_gpmc_controller);
2248 		omap_gpmc_controller_initialized = true;
2249 	}
2250 
2251 	nand_chip->controller = &omap_gpmc_controller;
2252 
2253 	info->ready_gpiod = devm_gpiod_get_optional(&pdev->dev, "rb",
2254 						    GPIOD_IN);
2255 	if (IS_ERR(info->ready_gpiod)) {
2256 		dev_err(dev, "failed to get ready gpio\n");
2257 		return PTR_ERR(info->ready_gpiod);
2258 	}
2259 
2260 	if (info->flash_bbt)
2261 		nand_chip->bbt_options |= NAND_BBT_USE_FLASH;
2262 
2263 	/* default operations */
2264 	info->data_in = omap_nand_data_in;
2265 	info->data_out = omap_nand_data_out;
2266 
2267 	err = nand_scan(nand_chip, 1);
2268 	if (err)
2269 		goto return_error;
2270 
2271 	err = mtd_device_register(mtd, NULL, 0);
2272 	if (err)
2273 		goto cleanup_nand;
2274 
2275 	platform_set_drvdata(pdev, mtd);
2276 
2277 	return 0;
2278 
2279 cleanup_nand:
2280 	nand_cleanup(nand_chip);
2281 
2282 return_error:
2283 	if (!IS_ERR_OR_NULL(info->dma))
2284 		dma_release_channel(info->dma);
2285 
2286 	rawnand_sw_bch_cleanup(nand_chip);
2287 
2288 	return err;
2289 }
2290 
omap_nand_remove(struct platform_device * pdev)2291 static void omap_nand_remove(struct platform_device *pdev)
2292 {
2293 	struct mtd_info *mtd = platform_get_drvdata(pdev);
2294 	struct nand_chip *nand_chip = mtd_to_nand(mtd);
2295 	struct omap_nand_info *info = mtd_to_omap(mtd);
2296 
2297 	rawnand_sw_bch_cleanup(nand_chip);
2298 
2299 	if (info->dma)
2300 		dma_release_channel(info->dma);
2301 	WARN_ON(mtd_device_unregister(mtd));
2302 	nand_cleanup(nand_chip);
2303 }
2304 
2305 /* omap_nand_ids defined in linux/platform_data/mtd-nand-omap2.h */
2306 MODULE_DEVICE_TABLE(of, omap_nand_ids);
2307 
2308 static struct platform_driver omap_nand_driver = {
2309 	.probe		= omap_nand_probe,
2310 	.remove		= omap_nand_remove,
2311 	.driver		= {
2312 		.name	= DRIVER_NAME,
2313 		.of_match_table = omap_nand_ids,
2314 	},
2315 };
2316 
2317 module_platform_driver(omap_nand_driver);
2318 
2319 MODULE_ALIAS("platform:" DRIVER_NAME);
2320 MODULE_LICENSE("GPL");
2321 MODULE_DESCRIPTION("Glue layer for NAND flash on TI OMAP boards");
2322