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1/*
2 * NAND Flash Controller Device Driver
3 * Copyright © 2009-2010, Intel Corporation and its suppliers.
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms and conditions of the GNU General Public License,
7 * version 2, as published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12 * more details.
13 *
14 * You should have received a copy of the GNU General Public License along with
15 * this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
17 *
18 */
19#include <linux/interrupt.h>
20#include <linux/delay.h>
21#include <linux/dma-mapping.h>
22#include <linux/wait.h>
23#include <linux/mutex.h>
24#include <linux/slab.h>
25#include <linux/mtd/mtd.h>
26#include <linux/module.h>
27
28#include "denali.h"
29
30MODULE_LICENSE("GPL");
31
32/*
33 * We define a module parameter that allows the user to override
34 * the hardware and decide what timing mode should be used.
35 */
36#define NAND_DEFAULT_TIMINGS	-1
37
38static int onfi_timing_mode = NAND_DEFAULT_TIMINGS;
39module_param(onfi_timing_mode, int, S_IRUGO);
40MODULE_PARM_DESC(onfi_timing_mode,
41	   "Overrides default ONFI setting. -1 indicates use default timings");
42
43#define DENALI_NAND_NAME    "denali-nand"
44
45/*
46 * We define a macro here that combines all interrupts this driver uses into
47 * a single constant value, for convenience.
48 */
49#define DENALI_IRQ_ALL	(INTR_STATUS__DMA_CMD_COMP | \
50			INTR_STATUS__ECC_TRANSACTION_DONE | \
51			INTR_STATUS__ECC_ERR | \
52			INTR_STATUS__PROGRAM_FAIL | \
53			INTR_STATUS__LOAD_COMP | \
54			INTR_STATUS__PROGRAM_COMP | \
55			INTR_STATUS__TIME_OUT | \
56			INTR_STATUS__ERASE_FAIL | \
57			INTR_STATUS__RST_COMP | \
58			INTR_STATUS__ERASE_COMP)
59
60/*
61 * indicates whether or not the internal value for the flash bank is
62 * valid or not
63 */
64#define CHIP_SELECT_INVALID	-1
65
66#define SUPPORT_8BITECC		1
67
68/*
69 * This macro divides two integers and rounds fractional values up
70 * to the nearest integer value.
71 */
72#define CEIL_DIV(X, Y) (((X)%(Y)) ? ((X)/(Y)+1) : ((X)/(Y)))
73
74/*
75 * this macro allows us to convert from an MTD structure to our own
76 * device context (denali) structure.
77 */
78#define mtd_to_denali(m) container_of(m, struct denali_nand_info, mtd)
79
80/*
81 * These constants are defined by the driver to enable common driver
82 * configuration options.
83 */
84#define SPARE_ACCESS		0x41
85#define MAIN_ACCESS		0x42
86#define MAIN_SPARE_ACCESS	0x43
87#define PIPELINE_ACCESS		0x2000
88
89#define DENALI_READ	0
90#define DENALI_WRITE	0x100
91
92/* types of device accesses. We can issue commands and get status */
93#define COMMAND_CYCLE	0
94#define ADDR_CYCLE	1
95#define STATUS_CYCLE	2
96
97/*
98 * this is a helper macro that allows us to
99 * format the bank into the proper bits for the controller
100 */
101#define BANK(x) ((x) << 24)
102
103/* forward declarations */
104static void clear_interrupts(struct denali_nand_info *denali);
105static uint32_t wait_for_irq(struct denali_nand_info *denali,
106							uint32_t irq_mask);
107static void denali_irq_enable(struct denali_nand_info *denali,
108							uint32_t int_mask);
109static uint32_t read_interrupt_status(struct denali_nand_info *denali);
110
111/*
112 * Certain operations for the denali NAND controller use an indexed mode to
113 * read/write data. The operation is performed by writing the address value
114 * of the command to the device memory followed by the data. This function
115 * abstracts this common operation.
116 */
117static void index_addr(struct denali_nand_info *denali,
118				uint32_t address, uint32_t data)
119{
120	iowrite32(address, denali->flash_mem);
121	iowrite32(data, denali->flash_mem + 0x10);
122}
123
124/* Perform an indexed read of the device */
125static void index_addr_read_data(struct denali_nand_info *denali,
126				 uint32_t address, uint32_t *pdata)
127{
128	iowrite32(address, denali->flash_mem);
129	*pdata = ioread32(denali->flash_mem + 0x10);
130}
131
132/*
133 * We need to buffer some data for some of the NAND core routines.
134 * The operations manage buffering that data.
135 */
136static void reset_buf(struct denali_nand_info *denali)
137{
138	denali->buf.head = denali->buf.tail = 0;
139}
140
141static void write_byte_to_buf(struct denali_nand_info *denali, uint8_t byte)
142{
143	denali->buf.buf[denali->buf.tail++] = byte;
144}
145
146/* reads the status of the device */
147static void read_status(struct denali_nand_info *denali)
148{
149	uint32_t cmd;
150
151	/* initialize the data buffer to store status */
152	reset_buf(denali);
153
154	cmd = ioread32(denali->flash_reg + WRITE_PROTECT);
155	if (cmd)
156		write_byte_to_buf(denali, NAND_STATUS_WP);
157	else
158		write_byte_to_buf(denali, 0);
159}
160
161/* resets a specific device connected to the core */
162static void reset_bank(struct denali_nand_info *denali)
163{
164	uint32_t irq_status;
165	uint32_t irq_mask = INTR_STATUS__RST_COMP | INTR_STATUS__TIME_OUT;
166
167	clear_interrupts(denali);
168
169	iowrite32(1 << denali->flash_bank, denali->flash_reg + DEVICE_RESET);
170
171	irq_status = wait_for_irq(denali, irq_mask);
172
173	if (irq_status & INTR_STATUS__TIME_OUT)
174		dev_err(denali->dev, "reset bank failed.\n");
175}
176
177/* Reset the flash controller */
178static uint16_t denali_nand_reset(struct denali_nand_info *denali)
179{
180	int i;
181
182	dev_dbg(denali->dev, "%s, Line %d, Function: %s\n",
183		__FILE__, __LINE__, __func__);
184
185	for (i = 0; i < denali->max_banks; i++)
186		iowrite32(INTR_STATUS__RST_COMP | INTR_STATUS__TIME_OUT,
187		denali->flash_reg + INTR_STATUS(i));
188
189	for (i = 0; i < denali->max_banks; i++) {
190		iowrite32(1 << i, denali->flash_reg + DEVICE_RESET);
191		while (!(ioread32(denali->flash_reg + INTR_STATUS(i)) &
192			(INTR_STATUS__RST_COMP | INTR_STATUS__TIME_OUT)))
193			cpu_relax();
194		if (ioread32(denali->flash_reg + INTR_STATUS(i)) &
195			INTR_STATUS__TIME_OUT)
196			dev_dbg(denali->dev,
197			"NAND Reset operation timed out on bank %d\n", i);
198	}
199
200	for (i = 0; i < denali->max_banks; i++)
201		iowrite32(INTR_STATUS__RST_COMP | INTR_STATUS__TIME_OUT,
202			  denali->flash_reg + INTR_STATUS(i));
203
204	return PASS;
205}
206
207/*
208 * this routine calculates the ONFI timing values for a given mode and
209 * programs the clocking register accordingly. The mode is determined by
210 * the get_onfi_nand_para routine.
211 */
212static void nand_onfi_timing_set(struct denali_nand_info *denali,
213								uint16_t mode)
214{
215	uint16_t Trea[6] = {40, 30, 25, 20, 20, 16};
216	uint16_t Trp[6] = {50, 25, 17, 15, 12, 10};
217	uint16_t Treh[6] = {30, 15, 15, 10, 10, 7};
218	uint16_t Trc[6] = {100, 50, 35, 30, 25, 20};
219	uint16_t Trhoh[6] = {0, 15, 15, 15, 15, 15};
220	uint16_t Trloh[6] = {0, 0, 0, 0, 5, 5};
221	uint16_t Tcea[6] = {100, 45, 30, 25, 25, 25};
222	uint16_t Tadl[6] = {200, 100, 100, 100, 70, 70};
223	uint16_t Trhw[6] = {200, 100, 100, 100, 100, 100};
224	uint16_t Trhz[6] = {200, 100, 100, 100, 100, 100};
225	uint16_t Twhr[6] = {120, 80, 80, 60, 60, 60};
226	uint16_t Tcs[6] = {70, 35, 25, 25, 20, 15};
227
228	uint16_t TclsRising = 1;
229	uint16_t data_invalid_rhoh, data_invalid_rloh, data_invalid;
230	uint16_t dv_window = 0;
231	uint16_t en_lo, en_hi;
232	uint16_t acc_clks;
233	uint16_t addr_2_data, re_2_we, re_2_re, we_2_re, cs_cnt;
234
235	dev_dbg(denali->dev, "%s, Line %d, Function: %s\n",
236		__FILE__, __LINE__, __func__);
237
238	en_lo = CEIL_DIV(Trp[mode], CLK_X);
239	en_hi = CEIL_DIV(Treh[mode], CLK_X);
240#if ONFI_BLOOM_TIME
241	if ((en_hi * CLK_X) < (Treh[mode] + 2))
242		en_hi++;
243#endif
244
245	if ((en_lo + en_hi) * CLK_X < Trc[mode])
246		en_lo += CEIL_DIV((Trc[mode] - (en_lo + en_hi) * CLK_X), CLK_X);
247
248	if ((en_lo + en_hi) < CLK_MULTI)
249		en_lo += CLK_MULTI - en_lo - en_hi;
250
251	while (dv_window < 8) {
252		data_invalid_rhoh = en_lo * CLK_X + Trhoh[mode];
253
254		data_invalid_rloh = (en_lo + en_hi) * CLK_X + Trloh[mode];
255
256		data_invalid = data_invalid_rhoh < data_invalid_rloh ?
257					data_invalid_rhoh : data_invalid_rloh;
258
259		dv_window = data_invalid - Trea[mode];
260
261		if (dv_window < 8)
262			en_lo++;
263	}
264
265	acc_clks = CEIL_DIV(Trea[mode], CLK_X);
266
267	while (acc_clks * CLK_X - Trea[mode] < 3)
268		acc_clks++;
269
270	if (data_invalid - acc_clks * CLK_X < 2)
271		dev_warn(denali->dev, "%s, Line %d: Warning!\n",
272			 __FILE__, __LINE__);
273
274	addr_2_data = CEIL_DIV(Tadl[mode], CLK_X);
275	re_2_we = CEIL_DIV(Trhw[mode], CLK_X);
276	re_2_re = CEIL_DIV(Trhz[mode], CLK_X);
277	we_2_re = CEIL_DIV(Twhr[mode], CLK_X);
278	cs_cnt = CEIL_DIV((Tcs[mode] - Trp[mode]), CLK_X);
279	if (!TclsRising)
280		cs_cnt = CEIL_DIV(Tcs[mode], CLK_X);
281	if (cs_cnt == 0)
282		cs_cnt = 1;
283
284	if (Tcea[mode]) {
285		while (cs_cnt * CLK_X + Trea[mode] < Tcea[mode])
286			cs_cnt++;
287	}
288
289#if MODE5_WORKAROUND
290	if (mode == 5)
291		acc_clks = 5;
292#endif
293
294	/* Sighting 3462430: Temporary hack for MT29F128G08CJABAWP:B */
295	if (ioread32(denali->flash_reg + MANUFACTURER_ID) == 0 &&
296		ioread32(denali->flash_reg + DEVICE_ID) == 0x88)
297		acc_clks = 6;
298
299	iowrite32(acc_clks, denali->flash_reg + ACC_CLKS);
300	iowrite32(re_2_we, denali->flash_reg + RE_2_WE);
301	iowrite32(re_2_re, denali->flash_reg + RE_2_RE);
302	iowrite32(we_2_re, denali->flash_reg + WE_2_RE);
303	iowrite32(addr_2_data, denali->flash_reg + ADDR_2_DATA);
304	iowrite32(en_lo, denali->flash_reg + RDWR_EN_LO_CNT);
305	iowrite32(en_hi, denali->flash_reg + RDWR_EN_HI_CNT);
306	iowrite32(cs_cnt, denali->flash_reg + CS_SETUP_CNT);
307}
308
309/* queries the NAND device to see what ONFI modes it supports. */
310static uint16_t get_onfi_nand_para(struct denali_nand_info *denali)
311{
312	int i;
313
314	/*
315	 * we needn't to do a reset here because driver has already
316	 * reset all the banks before
317	 */
318	if (!(ioread32(denali->flash_reg + ONFI_TIMING_MODE) &
319		ONFI_TIMING_MODE__VALUE))
320		return FAIL;
321
322	for (i = 5; i > 0; i--) {
323		if (ioread32(denali->flash_reg + ONFI_TIMING_MODE) &
324			(0x01 << i))
325			break;
326	}
327
328	nand_onfi_timing_set(denali, i);
329
330	/*
331	 * By now, all the ONFI devices we know support the page cache
332	 * rw feature. So here we enable the pipeline_rw_ahead feature
333	 */
334	/* iowrite32(1, denali->flash_reg + CACHE_WRITE_ENABLE); */
335	/* iowrite32(1, denali->flash_reg + CACHE_READ_ENABLE);  */
336
337	return PASS;
338}
339
340static void get_samsung_nand_para(struct denali_nand_info *denali,
341							uint8_t device_id)
342{
343	if (device_id == 0xd3) { /* Samsung K9WAG08U1A */
344		/* Set timing register values according to datasheet */
345		iowrite32(5, denali->flash_reg + ACC_CLKS);
346		iowrite32(20, denali->flash_reg + RE_2_WE);
347		iowrite32(12, denali->flash_reg + WE_2_RE);
348		iowrite32(14, denali->flash_reg + ADDR_2_DATA);
349		iowrite32(3, denali->flash_reg + RDWR_EN_LO_CNT);
350		iowrite32(2, denali->flash_reg + RDWR_EN_HI_CNT);
351		iowrite32(2, denali->flash_reg + CS_SETUP_CNT);
352	}
353}
354
355static void get_toshiba_nand_para(struct denali_nand_info *denali)
356{
357	uint32_t tmp;
358
359	/*
360	 * Workaround to fix a controller bug which reports a wrong
361	 * spare area size for some kind of Toshiba NAND device
362	 */
363	if ((ioread32(denali->flash_reg + DEVICE_MAIN_AREA_SIZE) == 4096) &&
364		(ioread32(denali->flash_reg + DEVICE_SPARE_AREA_SIZE) == 64)) {
365		iowrite32(216, denali->flash_reg + DEVICE_SPARE_AREA_SIZE);
366		tmp = ioread32(denali->flash_reg + DEVICES_CONNECTED) *
367			ioread32(denali->flash_reg + DEVICE_SPARE_AREA_SIZE);
368		iowrite32(tmp,
369				denali->flash_reg + LOGICAL_PAGE_SPARE_SIZE);
370#if SUPPORT_15BITECC
371		iowrite32(15, denali->flash_reg + ECC_CORRECTION);
372#elif SUPPORT_8BITECC
373		iowrite32(8, denali->flash_reg + ECC_CORRECTION);
374#endif
375	}
376}
377
378static void get_hynix_nand_para(struct denali_nand_info *denali,
379							uint8_t device_id)
380{
381	uint32_t main_size, spare_size;
382
383	switch (device_id) {
384	case 0xD5: /* Hynix H27UAG8T2A, H27UBG8U5A or H27UCG8VFA */
385	case 0xD7: /* Hynix H27UDG8VEM, H27UCG8UDM or H27UCG8V5A */
386		iowrite32(128, denali->flash_reg + PAGES_PER_BLOCK);
387		iowrite32(4096, denali->flash_reg + DEVICE_MAIN_AREA_SIZE);
388		iowrite32(224, denali->flash_reg + DEVICE_SPARE_AREA_SIZE);
389		main_size = 4096 *
390			ioread32(denali->flash_reg + DEVICES_CONNECTED);
391		spare_size = 224 *
392			ioread32(denali->flash_reg + DEVICES_CONNECTED);
393		iowrite32(main_size,
394				denali->flash_reg + LOGICAL_PAGE_DATA_SIZE);
395		iowrite32(spare_size,
396				denali->flash_reg + LOGICAL_PAGE_SPARE_SIZE);
397		iowrite32(0, denali->flash_reg + DEVICE_WIDTH);
398#if SUPPORT_15BITECC
399		iowrite32(15, denali->flash_reg + ECC_CORRECTION);
400#elif SUPPORT_8BITECC
401		iowrite32(8, denali->flash_reg + ECC_CORRECTION);
402#endif
403		break;
404	default:
405		dev_warn(denali->dev,
406			 "Spectra: Unknown Hynix NAND (Device ID: 0x%x).\n"
407			 "Will use default parameter values instead.\n",
408			 device_id);
409	}
410}
411
412/*
413 * determines how many NAND chips are connected to the controller. Note for
414 * Intel CE4100 devices we don't support more than one device.
415 */
416static void find_valid_banks(struct denali_nand_info *denali)
417{
418	uint32_t id[denali->max_banks];
419	int i;
420
421	denali->total_used_banks = 1;
422	for (i = 0; i < denali->max_banks; i++) {
423		index_addr(denali, MODE_11 | (i << 24) | 0, 0x90);
424		index_addr(denali, MODE_11 | (i << 24) | 1, 0);
425		index_addr_read_data(denali, MODE_11 | (i << 24) | 2, &id[i]);
426
427		dev_dbg(denali->dev,
428			"Return 1st ID for bank[%d]: %x\n", i, id[i]);
429
430		if (i == 0) {
431			if (!(id[i] & 0x0ff))
432				break; /* WTF? */
433		} else {
434			if ((id[i] & 0x0ff) == (id[0] & 0x0ff))
435				denali->total_used_banks++;
436			else
437				break;
438		}
439	}
440
441	if (denali->platform == INTEL_CE4100) {
442		/*
443		 * Platform limitations of the CE4100 device limit
444		 * users to a single chip solution for NAND.
445		 * Multichip support is not enabled.
446		 */
447		if (denali->total_used_banks != 1) {
448			dev_err(denali->dev,
449				"Sorry, Intel CE4100 only supports a single NAND device.\n");
450			BUG();
451		}
452	}
453	dev_dbg(denali->dev,
454		"denali->total_used_banks: %d\n", denali->total_used_banks);
455}
456
457/*
458 * Use the configuration feature register to determine the maximum number of
459 * banks that the hardware supports.
460 */
461static void detect_max_banks(struct denali_nand_info *denali)
462{
463	uint32_t features = ioread32(denali->flash_reg + FEATURES);
464
465	denali->max_banks = 2 << (features & FEATURES__N_BANKS);
466}
467
468static void detect_partition_feature(struct denali_nand_info *denali)
469{
470	/*
471	 * For MRST platform, denali->fwblks represent the
472	 * number of blocks firmware is taken,
473	 * FW is in protect partition and MTD driver has no
474	 * permission to access it. So let driver know how many
475	 * blocks it can't touch.
476	 */
477	if (ioread32(denali->flash_reg + FEATURES) & FEATURES__PARTITION) {
478		if ((ioread32(denali->flash_reg + PERM_SRC_ID(1)) &
479			PERM_SRC_ID__SRCID) == SPECTRA_PARTITION_ID) {
480			denali->fwblks =
481			    ((ioread32(denali->flash_reg + MIN_MAX_BANK(1)) &
482			      MIN_MAX_BANK__MIN_VALUE) *
483			     denali->blksperchip)
484			    +
485			    (ioread32(denali->flash_reg + MIN_BLK_ADDR(1)) &
486			    MIN_BLK_ADDR__VALUE);
487		} else {
488			denali->fwblks = SPECTRA_START_BLOCK;
489		}
490	} else {
491		denali->fwblks = SPECTRA_START_BLOCK;
492	}
493}
494
495static uint16_t denali_nand_timing_set(struct denali_nand_info *denali)
496{
497	uint16_t status = PASS;
498	uint32_t id_bytes[8], addr;
499	uint8_t maf_id, device_id;
500	int i;
501
502	dev_dbg(denali->dev, "%s, Line %d, Function: %s\n",
503			__FILE__, __LINE__, __func__);
504
505	/*
506	 * Use read id method to get device ID and other params.
507	 * For some NAND chips, controller can't report the correct
508	 * device ID by reading from DEVICE_ID register
509	 */
510	addr = MODE_11 | BANK(denali->flash_bank);
511	index_addr(denali, addr | 0, 0x90);
512	index_addr(denali, addr | 1, 0);
513	for (i = 0; i < 8; i++)
514		index_addr_read_data(denali, addr | 2, &id_bytes[i]);
515	maf_id = id_bytes[0];
516	device_id = id_bytes[1];
517
518	if (ioread32(denali->flash_reg + ONFI_DEVICE_NO_OF_LUNS) &
519		ONFI_DEVICE_NO_OF_LUNS__ONFI_DEVICE) { /* ONFI 1.0 NAND */
520		if (FAIL == get_onfi_nand_para(denali))
521			return FAIL;
522	} else if (maf_id == 0xEC) { /* Samsung NAND */
523		get_samsung_nand_para(denali, device_id);
524	} else if (maf_id == 0x98) { /* Toshiba NAND */
525		get_toshiba_nand_para(denali);
526	} else if (maf_id == 0xAD) { /* Hynix NAND */
527		get_hynix_nand_para(denali, device_id);
528	}
529
530	dev_info(denali->dev,
531			"Dump timing register values:\n"
532			"acc_clks: %d, re_2_we: %d, re_2_re: %d\n"
533			"we_2_re: %d, addr_2_data: %d, rdwr_en_lo_cnt: %d\n"
534			"rdwr_en_hi_cnt: %d, cs_setup_cnt: %d\n",
535			ioread32(denali->flash_reg + ACC_CLKS),
536			ioread32(denali->flash_reg + RE_2_WE),
537			ioread32(denali->flash_reg + RE_2_RE),
538			ioread32(denali->flash_reg + WE_2_RE),
539			ioread32(denali->flash_reg + ADDR_2_DATA),
540			ioread32(denali->flash_reg + RDWR_EN_LO_CNT),
541			ioread32(denali->flash_reg + RDWR_EN_HI_CNT),
542			ioread32(denali->flash_reg + CS_SETUP_CNT));
543
544	find_valid_banks(denali);
545
546	detect_partition_feature(denali);
547
548	/*
549	 * If the user specified to override the default timings
550	 * with a specific ONFI mode, we apply those changes here.
551	 */
552	if (onfi_timing_mode != NAND_DEFAULT_TIMINGS)
553		nand_onfi_timing_set(denali, onfi_timing_mode);
554
555	return status;
556}
557
558static void denali_set_intr_modes(struct denali_nand_info *denali,
559					uint16_t INT_ENABLE)
560{
561	dev_dbg(denali->dev, "%s, Line %d, Function: %s\n",
562		__FILE__, __LINE__, __func__);
563
564	if (INT_ENABLE)
565		iowrite32(1, denali->flash_reg + GLOBAL_INT_ENABLE);
566	else
567		iowrite32(0, denali->flash_reg + GLOBAL_INT_ENABLE);
568}
569
570/*
571 * validation function to verify that the controlling software is making
572 * a valid request
573 */
574static inline bool is_flash_bank_valid(int flash_bank)
575{
576	return flash_bank >= 0 && flash_bank < 4;
577}
578
579static void denali_irq_init(struct denali_nand_info *denali)
580{
581	uint32_t int_mask;
582	int i;
583
584	/* Disable global interrupts */
585	denali_set_intr_modes(denali, false);
586
587	int_mask = DENALI_IRQ_ALL;
588
589	/* Clear all status bits */
590	for (i = 0; i < denali->max_banks; ++i)
591		iowrite32(0xFFFF, denali->flash_reg + INTR_STATUS(i));
592
593	denali_irq_enable(denali, int_mask);
594}
595
596static void denali_irq_cleanup(int irqnum, struct denali_nand_info *denali)
597{
598	denali_set_intr_modes(denali, false);
599	free_irq(irqnum, denali);
600}
601
602static void denali_irq_enable(struct denali_nand_info *denali,
603							uint32_t int_mask)
604{
605	int i;
606
607	for (i = 0; i < denali->max_banks; ++i)
608		iowrite32(int_mask, denali->flash_reg + INTR_EN(i));
609}
610
611/*
612 * This function only returns when an interrupt that this driver cares about
613 * occurs. This is to reduce the overhead of servicing interrupts
614 */
615static inline uint32_t denali_irq_detected(struct denali_nand_info *denali)
616{
617	return read_interrupt_status(denali) & DENALI_IRQ_ALL;
618}
619
620/* Interrupts are cleared by writing a 1 to the appropriate status bit */
621static inline void clear_interrupt(struct denali_nand_info *denali,
622							uint32_t irq_mask)
623{
624	uint32_t intr_status_reg;
625
626	intr_status_reg = INTR_STATUS(denali->flash_bank);
627
628	iowrite32(irq_mask, denali->flash_reg + intr_status_reg);
629}
630
631static void clear_interrupts(struct denali_nand_info *denali)
632{
633	uint32_t status;
634
635	spin_lock_irq(&denali->irq_lock);
636
637	status = read_interrupt_status(denali);
638	clear_interrupt(denali, status);
639
640	denali->irq_status = 0x0;
641	spin_unlock_irq(&denali->irq_lock);
642}
643
644static uint32_t read_interrupt_status(struct denali_nand_info *denali)
645{
646	uint32_t intr_status_reg;
647
648	intr_status_reg = INTR_STATUS(denali->flash_bank);
649
650	return ioread32(denali->flash_reg + intr_status_reg);
651}
652
653/*
654 * This is the interrupt service routine. It handles all interrupts
655 * sent to this device. Note that on CE4100, this is a shared interrupt.
656 */
657static irqreturn_t denali_isr(int irq, void *dev_id)
658{
659	struct denali_nand_info *denali = dev_id;
660	uint32_t irq_status;
661	irqreturn_t result = IRQ_NONE;
662
663	spin_lock(&denali->irq_lock);
664
665	/* check to see if a valid NAND chip has been selected. */
666	if (is_flash_bank_valid(denali->flash_bank)) {
667		/*
668		 * check to see if controller generated the interrupt,
669		 * since this is a shared interrupt
670		 */
671		irq_status = denali_irq_detected(denali);
672		if (irq_status != 0) {
673			/* handle interrupt */
674			/* first acknowledge it */
675			clear_interrupt(denali, irq_status);
676			/*
677			 * store the status in the device context for someone
678			 * to read
679			 */
680			denali->irq_status |= irq_status;
681			/* notify anyone who cares that it happened */
682			complete(&denali->complete);
683			/* tell the OS that we've handled this */
684			result = IRQ_HANDLED;
685		}
686	}
687	spin_unlock(&denali->irq_lock);
688	return result;
689}
690#define BANK(x) ((x) << 24)
691
692static uint32_t wait_for_irq(struct denali_nand_info *denali, uint32_t irq_mask)
693{
694	unsigned long comp_res;
695	uint32_t intr_status;
696	unsigned long timeout = msecs_to_jiffies(1000);
697
698	do {
699		comp_res =
700			wait_for_completion_timeout(&denali->complete, timeout);
701		spin_lock_irq(&denali->irq_lock);
702		intr_status = denali->irq_status;
703
704		if (intr_status & irq_mask) {
705			denali->irq_status &= ~irq_mask;
706			spin_unlock_irq(&denali->irq_lock);
707			/* our interrupt was detected */
708			break;
709		}
710
711		/*
712		 * these are not the interrupts you are looking for -
713		 * need to wait again
714		 */
715		spin_unlock_irq(&denali->irq_lock);
716	} while (comp_res != 0);
717
718	if (comp_res == 0) {
719		/* timeout */
720		pr_err("timeout occurred, status = 0x%x, mask = 0x%x\n",
721				intr_status, irq_mask);
722
723		intr_status = 0;
724	}
725	return intr_status;
726}
727
728/*
729 * This helper function setups the registers for ECC and whether or not
730 * the spare area will be transferred.
731 */
732static void setup_ecc_for_xfer(struct denali_nand_info *denali, bool ecc_en,
733				bool transfer_spare)
734{
735	int ecc_en_flag, transfer_spare_flag;
736
737	/* set ECC, transfer spare bits if needed */
738	ecc_en_flag = ecc_en ? ECC_ENABLE__FLAG : 0;
739	transfer_spare_flag = transfer_spare ? TRANSFER_SPARE_REG__FLAG : 0;
740
741	/* Enable spare area/ECC per user's request. */
742	iowrite32(ecc_en_flag, denali->flash_reg + ECC_ENABLE);
743	iowrite32(transfer_spare_flag, denali->flash_reg + TRANSFER_SPARE_REG);
744}
745
746/*
747 * sends a pipeline command operation to the controller. See the Denali NAND
748 * controller's user guide for more information (section 4.2.3.6).
749 */
750static int denali_send_pipeline_cmd(struct denali_nand_info *denali,
751				    bool ecc_en, bool transfer_spare,
752				    int access_type, int op)
753{
754	int status = PASS;
755	uint32_t page_count = 1;
756	uint32_t addr, cmd, irq_status, irq_mask;
757
758	if (op == DENALI_READ)
759		irq_mask = INTR_STATUS__LOAD_COMP;
760	else if (op == DENALI_WRITE)
761		irq_mask = 0;
762	else
763		BUG();
764
765	setup_ecc_for_xfer(denali, ecc_en, transfer_spare);
766
767	clear_interrupts(denali);
768
769	addr = BANK(denali->flash_bank) | denali->page;
770
771	if (op == DENALI_WRITE && access_type != SPARE_ACCESS) {
772		cmd = MODE_01 | addr;
773		iowrite32(cmd, denali->flash_mem);
774	} else if (op == DENALI_WRITE && access_type == SPARE_ACCESS) {
775		/* read spare area */
776		cmd = MODE_10 | addr;
777		index_addr(denali, cmd, access_type);
778
779		cmd = MODE_01 | addr;
780		iowrite32(cmd, denali->flash_mem);
781	} else if (op == DENALI_READ) {
782		/* setup page read request for access type */
783		cmd = MODE_10 | addr;
784		index_addr(denali, cmd, access_type);
785
786		/*
787		 * page 33 of the NAND controller spec indicates we should not
788		 * use the pipeline commands in Spare area only mode.
789		 * So we don't.
790		 */
791		if (access_type == SPARE_ACCESS) {
792			cmd = MODE_01 | addr;
793			iowrite32(cmd, denali->flash_mem);
794		} else {
795			index_addr(denali, cmd,
796					PIPELINE_ACCESS | op | page_count);
797
798			/*
799			 * wait for command to be accepted
800			 * can always use status0 bit as the
801			 * mask is identical for each bank.
802			 */
803			irq_status = wait_for_irq(denali, irq_mask);
804
805			if (irq_status == 0) {
806				dev_err(denali->dev,
807					"cmd, page, addr on timeout (0x%x, 0x%x, 0x%x)\n",
808					cmd, denali->page, addr);
809				status = FAIL;
810			} else {
811				cmd = MODE_01 | addr;
812				iowrite32(cmd, denali->flash_mem);
813			}
814		}
815	}
816	return status;
817}
818
819/* helper function that simply writes a buffer to the flash */
820static int write_data_to_flash_mem(struct denali_nand_info *denali,
821				   const uint8_t *buf, int len)
822{
823	uint32_t *buf32;
824	int i;
825
826	/*
827	 * verify that the len is a multiple of 4.
828	 * see comment in read_data_from_flash_mem()
829	 */
830	BUG_ON((len % 4) != 0);
831
832	/* write the data to the flash memory */
833	buf32 = (uint32_t *)buf;
834	for (i = 0; i < len / 4; i++)
835		iowrite32(*buf32++, denali->flash_mem + 0x10);
836	return i * 4; /* intent is to return the number of bytes read */
837}
838
839/* helper function that simply reads a buffer from the flash */
840static int read_data_from_flash_mem(struct denali_nand_info *denali,
841				    uint8_t *buf, int len)
842{
843	uint32_t *buf32;
844	int i;
845
846	/*
847	 * we assume that len will be a multiple of 4, if not it would be nice
848	 * to know about it ASAP rather than have random failures...
849	 * This assumption is based on the fact that this function is designed
850	 * to be used to read flash pages, which are typically multiples of 4.
851	 */
852	BUG_ON((len % 4) != 0);
853
854	/* transfer the data from the flash */
855	buf32 = (uint32_t *)buf;
856	for (i = 0; i < len / 4; i++)
857		*buf32++ = ioread32(denali->flash_mem + 0x10);
858	return i * 4; /* intent is to return the number of bytes read */
859}
860
861/* writes OOB data to the device */
862static int write_oob_data(struct mtd_info *mtd, uint8_t *buf, int page)
863{
864	struct denali_nand_info *denali = mtd_to_denali(mtd);
865	uint32_t irq_status;
866	uint32_t irq_mask = INTR_STATUS__PROGRAM_COMP |
867						INTR_STATUS__PROGRAM_FAIL;
868	int status = 0;
869
870	denali->page = page;
871
872	if (denali_send_pipeline_cmd(denali, false, false, SPARE_ACCESS,
873							DENALI_WRITE) == PASS) {
874		write_data_to_flash_mem(denali, buf, mtd->oobsize);
875
876		/* wait for operation to complete */
877		irq_status = wait_for_irq(denali, irq_mask);
878
879		if (irq_status == 0) {
880			dev_err(denali->dev, "OOB write failed\n");
881			status = -EIO;
882		}
883	} else {
884		dev_err(denali->dev, "unable to send pipeline command\n");
885		status = -EIO;
886	}
887	return status;
888}
889
890/* reads OOB data from the device */
891static void read_oob_data(struct mtd_info *mtd, uint8_t *buf, int page)
892{
893	struct denali_nand_info *denali = mtd_to_denali(mtd);
894	uint32_t irq_mask = INTR_STATUS__LOAD_COMP;
895	uint32_t irq_status, addr, cmd;
896
897	denali->page = page;
898
899	if (denali_send_pipeline_cmd(denali, false, true, SPARE_ACCESS,
900							DENALI_READ) == PASS) {
901		read_data_from_flash_mem(denali, buf, mtd->oobsize);
902
903		/*
904		 * wait for command to be accepted
905		 * can always use status0 bit as the
906		 * mask is identical for each bank.
907		 */
908		irq_status = wait_for_irq(denali, irq_mask);
909
910		if (irq_status == 0)
911			dev_err(denali->dev, "page on OOB timeout %d\n",
912					denali->page);
913
914		/*
915		 * We set the device back to MAIN_ACCESS here as I observed
916		 * instability with the controller if you do a block erase
917		 * and the last transaction was a SPARE_ACCESS. Block erase
918		 * is reliable (according to the MTD test infrastructure)
919		 * if you are in MAIN_ACCESS.
920		 */
921		addr = BANK(denali->flash_bank) | denali->page;
922		cmd = MODE_10 | addr;
923		index_addr(denali, cmd, MAIN_ACCESS);
924	}
925}
926
927/*
928 * this function examines buffers to see if they contain data that
929 * indicate that the buffer is part of an erased region of flash.
930 */
931static bool is_erased(uint8_t *buf, int len)
932{
933	int i;
934
935	for (i = 0; i < len; i++)
936		if (buf[i] != 0xFF)
937			return false;
938	return true;
939}
940#define ECC_SECTOR_SIZE 512
941
942#define ECC_SECTOR(x)	(((x) & ECC_ERROR_ADDRESS__SECTOR_NR) >> 12)
943#define ECC_BYTE(x)	(((x) & ECC_ERROR_ADDRESS__OFFSET))
944#define ECC_CORRECTION_VALUE(x) ((x) & ERR_CORRECTION_INFO__BYTEMASK)
945#define ECC_ERROR_CORRECTABLE(x) (!((x) & ERR_CORRECTION_INFO__ERROR_TYPE))
946#define ECC_ERR_DEVICE(x)	(((x) & ERR_CORRECTION_INFO__DEVICE_NR) >> 8)
947#define ECC_LAST_ERR(x)		((x) & ERR_CORRECTION_INFO__LAST_ERR_INFO)
948
949static bool handle_ecc(struct denali_nand_info *denali, uint8_t *buf,
950		       uint32_t irq_status, unsigned int *max_bitflips)
951{
952	bool check_erased_page = false;
953	unsigned int bitflips = 0;
954
955	if (irq_status & INTR_STATUS__ECC_ERR) {
956		/* read the ECC errors. we'll ignore them for now */
957		uint32_t err_address, err_correction_info, err_byte,
958			 err_sector, err_device, err_correction_value;
959		denali_set_intr_modes(denali, false);
960
961		do {
962			err_address = ioread32(denali->flash_reg +
963						ECC_ERROR_ADDRESS);
964			err_sector = ECC_SECTOR(err_address);
965			err_byte = ECC_BYTE(err_address);
966
967			err_correction_info = ioread32(denali->flash_reg +
968						ERR_CORRECTION_INFO);
969			err_correction_value =
970				ECC_CORRECTION_VALUE(err_correction_info);
971			err_device = ECC_ERR_DEVICE(err_correction_info);
972
973			if (ECC_ERROR_CORRECTABLE(err_correction_info)) {
974				/*
975				 * If err_byte is larger than ECC_SECTOR_SIZE,
976				 * means error happened in OOB, so we ignore
977				 * it. It's no need for us to correct it
978				 * err_device is represented the NAND error
979				 * bits are happened in if there are more
980				 * than one NAND connected.
981				 */
982				if (err_byte < ECC_SECTOR_SIZE) {
983					int offset;
984
985					offset = (err_sector *
986							ECC_SECTOR_SIZE +
987							err_byte) *
988							denali->devnum +
989							err_device;
990					/* correct the ECC error */
991					buf[offset] ^= err_correction_value;
992					denali->mtd.ecc_stats.corrected++;
993					bitflips++;
994				}
995			} else {
996				/*
997				 * if the error is not correctable, need to
998				 * look at the page to see if it is an erased
999				 * page. if so, then it's not a real ECC error
1000				 */
1001				check_erased_page = true;
1002			}
1003		} while (!ECC_LAST_ERR(err_correction_info));
1004		/*
1005		 * Once handle all ecc errors, controller will triger
1006		 * a ECC_TRANSACTION_DONE interrupt, so here just wait
1007		 * for a while for this interrupt
1008		 */
1009		while (!(read_interrupt_status(denali) &
1010				INTR_STATUS__ECC_TRANSACTION_DONE))
1011			cpu_relax();
1012		clear_interrupts(denali);
1013		denali_set_intr_modes(denali, true);
1014	}
1015	*max_bitflips = bitflips;
1016	return check_erased_page;
1017}
1018
1019/* programs the controller to either enable/disable DMA transfers */
1020static void denali_enable_dma(struct denali_nand_info *denali, bool en)
1021{
1022	iowrite32(en ? DMA_ENABLE__FLAG : 0, denali->flash_reg + DMA_ENABLE);
1023	ioread32(denali->flash_reg + DMA_ENABLE);
1024}
1025
1026/* setups the HW to perform the data DMA */
1027static void denali_setup_dma(struct denali_nand_info *denali, int op)
1028{
1029	uint32_t mode;
1030	const int page_count = 1;
1031	uint32_t addr = denali->buf.dma_buf;
1032
1033	mode = MODE_10 | BANK(denali->flash_bank);
1034
1035	/* DMA is a four step process */
1036
1037	/* 1. setup transfer type and # of pages */
1038	index_addr(denali, mode | denali->page, 0x2000 | op | page_count);
1039
1040	/* 2. set memory high address bits 23:8 */
1041	index_addr(denali, mode | ((addr >> 16) << 8), 0x2200);
1042
1043	/* 3. set memory low address bits 23:8 */
1044	index_addr(denali, mode | ((addr & 0xff) << 8), 0x2300);
1045
1046	/* 4. interrupt when complete, burst len = 64 bytes */
1047	index_addr(denali, mode | 0x14000, 0x2400);
1048}
1049
1050/*
1051 * writes a page. user specifies type, and this function handles the
1052 * configuration details.
1053 */
1054static int write_page(struct mtd_info *mtd, struct nand_chip *chip,
1055			const uint8_t *buf, bool raw_xfer)
1056{
1057	struct denali_nand_info *denali = mtd_to_denali(mtd);
1058	dma_addr_t addr = denali->buf.dma_buf;
1059	size_t size = denali->mtd.writesize + denali->mtd.oobsize;
1060	uint32_t irq_status;
1061	uint32_t irq_mask = INTR_STATUS__DMA_CMD_COMP |
1062						INTR_STATUS__PROGRAM_FAIL;
1063
1064	/*
1065	 * if it is a raw xfer, we want to disable ecc and send the spare area.
1066	 * !raw_xfer - enable ecc
1067	 * raw_xfer - transfer spare
1068	 */
1069	setup_ecc_for_xfer(denali, !raw_xfer, raw_xfer);
1070
1071	/* copy buffer into DMA buffer */
1072	memcpy(denali->buf.buf, buf, mtd->writesize);
1073
1074	if (raw_xfer) {
1075		/* transfer the data to the spare area */
1076		memcpy(denali->buf.buf + mtd->writesize,
1077			chip->oob_poi,
1078			mtd->oobsize);
1079	}
1080
1081	dma_sync_single_for_device(denali->dev, addr, size, DMA_TO_DEVICE);
1082
1083	clear_interrupts(denali);
1084	denali_enable_dma(denali, true);
1085
1086	denali_setup_dma(denali, DENALI_WRITE);
1087
1088	/* wait for operation to complete */
1089	irq_status = wait_for_irq(denali, irq_mask);
1090
1091	if (irq_status == 0) {
1092		dev_err(denali->dev, "timeout on write_page (type = %d)\n",
1093			raw_xfer);
1094		denali->status = NAND_STATUS_FAIL;
1095	}
1096
1097	denali_enable_dma(denali, false);
1098	dma_sync_single_for_cpu(denali->dev, addr, size, DMA_TO_DEVICE);
1099
1100	return 0;
1101}
1102
1103/* NAND core entry points */
1104
1105/*
1106 * this is the callback that the NAND core calls to write a page. Since
1107 * writing a page with ECC or without is similar, all the work is done
1108 * by write_page above.
1109 */
1110static int denali_write_page(struct mtd_info *mtd, struct nand_chip *chip,
1111				const uint8_t *buf, int oob_required)
1112{
1113	/*
1114	 * for regular page writes, we let HW handle all the ECC
1115	 * data written to the device.
1116	 */
1117	return write_page(mtd, chip, buf, false);
1118}
1119
1120/*
1121 * This is the callback that the NAND core calls to write a page without ECC.
1122 * raw access is similar to ECC page writes, so all the work is done in the
1123 * write_page() function above.
1124 */
1125static int denali_write_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
1126					const uint8_t *buf, int oob_required)
1127{
1128	/*
1129	 * for raw page writes, we want to disable ECC and simply write
1130	 * whatever data is in the buffer.
1131	 */
1132	return write_page(mtd, chip, buf, true);
1133}
1134
1135static int denali_write_oob(struct mtd_info *mtd, struct nand_chip *chip,
1136			    int page)
1137{
1138	return write_oob_data(mtd, chip->oob_poi, page);
1139}
1140
1141static int denali_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
1142			   int page)
1143{
1144	read_oob_data(mtd, chip->oob_poi, page);
1145
1146	return 0;
1147}
1148
1149static int denali_read_page(struct mtd_info *mtd, struct nand_chip *chip,
1150			    uint8_t *buf, int oob_required, int page)
1151{
1152	unsigned int max_bitflips;
1153	struct denali_nand_info *denali = mtd_to_denali(mtd);
1154
1155	dma_addr_t addr = denali->buf.dma_buf;
1156	size_t size = denali->mtd.writesize + denali->mtd.oobsize;
1157
1158	uint32_t irq_status;
1159	uint32_t irq_mask = INTR_STATUS__ECC_TRANSACTION_DONE |
1160			    INTR_STATUS__ECC_ERR;
1161	bool check_erased_page = false;
1162
1163	if (page != denali->page) {
1164		dev_err(denali->dev,
1165			"IN %s: page %d is not equal to denali->page %d",
1166			__func__, page, denali->page);
1167		BUG();
1168	}
1169
1170	setup_ecc_for_xfer(denali, true, false);
1171
1172	denali_enable_dma(denali, true);
1173	dma_sync_single_for_device(denali->dev, addr, size, DMA_FROM_DEVICE);
1174
1175	clear_interrupts(denali);
1176	denali_setup_dma(denali, DENALI_READ);
1177
1178	/* wait for operation to complete */
1179	irq_status = wait_for_irq(denali, irq_mask);
1180
1181	dma_sync_single_for_cpu(denali->dev, addr, size, DMA_FROM_DEVICE);
1182
1183	memcpy(buf, denali->buf.buf, mtd->writesize);
1184
1185	check_erased_page = handle_ecc(denali, buf, irq_status, &max_bitflips);
1186	denali_enable_dma(denali, false);
1187
1188	if (check_erased_page) {
1189		read_oob_data(&denali->mtd, chip->oob_poi, denali->page);
1190
1191		/* check ECC failures that may have occurred on erased pages */
1192		if (check_erased_page) {
1193			if (!is_erased(buf, denali->mtd.writesize))
1194				denali->mtd.ecc_stats.failed++;
1195			if (!is_erased(buf, denali->mtd.oobsize))
1196				denali->mtd.ecc_stats.failed++;
1197		}
1198	}
1199	return max_bitflips;
1200}
1201
1202static int denali_read_page_raw(struct mtd_info *mtd, struct nand_chip *chip,
1203				uint8_t *buf, int oob_required, int page)
1204{
1205	struct denali_nand_info *denali = mtd_to_denali(mtd);
1206	dma_addr_t addr = denali->buf.dma_buf;
1207	size_t size = denali->mtd.writesize + denali->mtd.oobsize;
1208	uint32_t irq_mask = INTR_STATUS__DMA_CMD_COMP;
1209
1210	if (page != denali->page) {
1211		dev_err(denali->dev,
1212			"IN %s: page %d is not equal to denali->page %d",
1213			__func__, page, denali->page);
1214		BUG();
1215	}
1216
1217	setup_ecc_for_xfer(denali, false, true);
1218	denali_enable_dma(denali, true);
1219
1220	dma_sync_single_for_device(denali->dev, addr, size, DMA_FROM_DEVICE);
1221
1222	clear_interrupts(denali);
1223	denali_setup_dma(denali, DENALI_READ);
1224
1225	/* wait for operation to complete */
1226	wait_for_irq(denali, irq_mask);
1227
1228	dma_sync_single_for_cpu(denali->dev, addr, size, DMA_FROM_DEVICE);
1229
1230	denali_enable_dma(denali, false);
1231
1232	memcpy(buf, denali->buf.buf, mtd->writesize);
1233	memcpy(chip->oob_poi, denali->buf.buf + mtd->writesize, mtd->oobsize);
1234
1235	return 0;
1236}
1237
1238static uint8_t denali_read_byte(struct mtd_info *mtd)
1239{
1240	struct denali_nand_info *denali = mtd_to_denali(mtd);
1241	uint8_t result = 0xff;
1242
1243	if (denali->buf.head < denali->buf.tail)
1244		result = denali->buf.buf[denali->buf.head++];
1245
1246	return result;
1247}
1248
1249static void denali_select_chip(struct mtd_info *mtd, int chip)
1250{
1251	struct denali_nand_info *denali = mtd_to_denali(mtd);
1252
1253	spin_lock_irq(&denali->irq_lock);
1254	denali->flash_bank = chip;
1255	spin_unlock_irq(&denali->irq_lock);
1256}
1257
1258static int denali_waitfunc(struct mtd_info *mtd, struct nand_chip *chip)
1259{
1260	struct denali_nand_info *denali = mtd_to_denali(mtd);
1261	int status = denali->status;
1262
1263	denali->status = 0;
1264
1265	return status;
1266}
1267
1268static int denali_erase(struct mtd_info *mtd, int page)
1269{
1270	struct denali_nand_info *denali = mtd_to_denali(mtd);
1271
1272	uint32_t cmd, irq_status;
1273
1274	clear_interrupts(denali);
1275
1276	/* setup page read request for access type */
1277	cmd = MODE_10 | BANK(denali->flash_bank) | page;
1278	index_addr(denali, cmd, 0x1);
1279
1280	/* wait for erase to complete or failure to occur */
1281	irq_status = wait_for_irq(denali, INTR_STATUS__ERASE_COMP |
1282					INTR_STATUS__ERASE_FAIL);
1283
1284	return irq_status & INTR_STATUS__ERASE_FAIL ? NAND_STATUS_FAIL : PASS;
1285}
1286
1287static void denali_cmdfunc(struct mtd_info *mtd, unsigned int cmd, int col,
1288			   int page)
1289{
1290	struct denali_nand_info *denali = mtd_to_denali(mtd);
1291	uint32_t addr, id;
1292	int i;
1293
1294	switch (cmd) {
1295	case NAND_CMD_PAGEPROG:
1296		break;
1297	case NAND_CMD_STATUS:
1298		read_status(denali);
1299		break;
1300	case NAND_CMD_READID:
1301	case NAND_CMD_PARAM:
1302		reset_buf(denali);
1303		/*
1304		 * sometimes ManufactureId read from register is not right
1305		 * e.g. some of Micron MT29F32G08QAA MLC NAND chips
1306		 * So here we send READID cmd to NAND insteand
1307		 */
1308		addr = MODE_11 | BANK(denali->flash_bank);
1309		index_addr(denali, addr | 0, 0x90);
1310		index_addr(denali, addr | 1, 0);
1311		for (i = 0; i < 8; i++) {
1312			index_addr_read_data(denali, addr | 2, &id);
1313			write_byte_to_buf(denali, id);
1314		}
1315		break;
1316	case NAND_CMD_READ0:
1317	case NAND_CMD_SEQIN:
1318		denali->page = page;
1319		break;
1320	case NAND_CMD_RESET:
1321		reset_bank(denali);
1322		break;
1323	case NAND_CMD_READOOB:
1324		/* TODO: Read OOB data */
1325		break;
1326	default:
1327		pr_err(": unsupported command received 0x%x\n", cmd);
1328		break;
1329	}
1330}
1331
1332/* stubs for ECC functions not used by the NAND core */
1333static int denali_ecc_calculate(struct mtd_info *mtd, const uint8_t *data,
1334				uint8_t *ecc_code)
1335{
1336	struct denali_nand_info *denali = mtd_to_denali(mtd);
1337
1338	dev_err(denali->dev, "denali_ecc_calculate called unexpectedly\n");
1339	BUG();
1340	return -EIO;
1341}
1342
1343static int denali_ecc_correct(struct mtd_info *mtd, uint8_t *data,
1344				uint8_t *read_ecc, uint8_t *calc_ecc)
1345{
1346	struct denali_nand_info *denali = mtd_to_denali(mtd);
1347
1348	dev_err(denali->dev, "denali_ecc_correct called unexpectedly\n");
1349	BUG();
1350	return -EIO;
1351}
1352
1353static void denali_ecc_hwctl(struct mtd_info *mtd, int mode)
1354{
1355	struct denali_nand_info *denali = mtd_to_denali(mtd);
1356
1357	dev_err(denali->dev, "denali_ecc_hwctl called unexpectedly\n");
1358	BUG();
1359}
1360/* end NAND core entry points */
1361
1362/* Initialization code to bring the device up to a known good state */
1363static void denali_hw_init(struct denali_nand_info *denali)
1364{
1365	/*
1366	 * tell driver how many bit controller will skip before
1367	 * writing ECC code in OOB, this register may be already
1368	 * set by firmware. So we read this value out.
1369	 * if this value is 0, just let it be.
1370	 */
1371	denali->bbtskipbytes = ioread32(denali->flash_reg +
1372						SPARE_AREA_SKIP_BYTES);
1373	detect_max_banks(denali);
1374	denali_nand_reset(denali);
1375	iowrite32(0x0F, denali->flash_reg + RB_PIN_ENABLED);
1376	iowrite32(CHIP_EN_DONT_CARE__FLAG,
1377			denali->flash_reg + CHIP_ENABLE_DONT_CARE);
1378
1379	iowrite32(0xffff, denali->flash_reg + SPARE_AREA_MARKER);
1380
1381	/* Should set value for these registers when init */
1382	iowrite32(0, denali->flash_reg + TWO_ROW_ADDR_CYCLES);
1383	iowrite32(1, denali->flash_reg + ECC_ENABLE);
1384	denali_nand_timing_set(denali);
1385	denali_irq_init(denali);
1386}
1387
1388/*
1389 * Althogh controller spec said SLC ECC is forceb to be 4bit,
1390 * but denali controller in MRST only support 15bit and 8bit ECC
1391 * correction
1392 */
1393#define ECC_8BITS	14
1394static struct nand_ecclayout nand_8bit_oob = {
1395	.eccbytes = 14,
1396};
1397
1398#define ECC_15BITS	26
1399static struct nand_ecclayout nand_15bit_oob = {
1400	.eccbytes = 26,
1401};
1402
1403static uint8_t bbt_pattern[] = {'B', 'b', 't', '0' };
1404static uint8_t mirror_pattern[] = {'1', 't', 'b', 'B' };
1405
1406static struct nand_bbt_descr bbt_main_descr = {
1407	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
1408		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
1409	.offs =	8,
1410	.len = 4,
1411	.veroffs = 12,
1412	.maxblocks = 4,
1413	.pattern = bbt_pattern,
1414};
1415
1416static struct nand_bbt_descr bbt_mirror_descr = {
1417	.options = NAND_BBT_LASTBLOCK | NAND_BBT_CREATE | NAND_BBT_WRITE
1418		| NAND_BBT_2BIT | NAND_BBT_VERSION | NAND_BBT_PERCHIP,
1419	.offs =	8,
1420	.len = 4,
1421	.veroffs = 12,
1422	.maxblocks = 4,
1423	.pattern = mirror_pattern,
1424};
1425
1426/* initialize driver data structures */
1427static void denali_drv_init(struct denali_nand_info *denali)
1428{
1429	denali->idx = 0;
1430
1431	/* setup interrupt handler */
1432	/*
1433	 * the completion object will be used to notify
1434	 * the callee that the interrupt is done
1435	 */
1436	init_completion(&denali->complete);
1437
1438	/*
1439	 * the spinlock will be used to synchronize the ISR with any
1440	 * element that might be access shared data (interrupt status)
1441	 */
1442	spin_lock_init(&denali->irq_lock);
1443
1444	/* indicate that MTD has not selected a valid bank yet */
1445	denali->flash_bank = CHIP_SELECT_INVALID;
1446
1447	/* initialize our irq_status variable to indicate no interrupts */
1448	denali->irq_status = 0;
1449}
1450
1451int denali_init(struct denali_nand_info *denali)
1452{
1453	int ret;
1454
1455	if (denali->platform == INTEL_CE4100) {
1456		/*
1457		 * Due to a silicon limitation, we can only support
1458		 * ONFI timing mode 1 and below.
1459		 */
1460		if (onfi_timing_mode < -1 || onfi_timing_mode > 1) {
1461			pr_err("Intel CE4100 only supports ONFI timing mode 1 or below\n");
1462			return -EINVAL;
1463		}
1464	}
1465
1466	/* allocate a temporary buffer for nand_scan_ident() */
1467	denali->buf.buf = devm_kzalloc(denali->dev, PAGE_SIZE,
1468					GFP_DMA | GFP_KERNEL);
1469	if (!denali->buf.buf)
1470		return -ENOMEM;
1471
1472	denali->mtd.dev.parent = denali->dev;
1473	denali_hw_init(denali);
1474	denali_drv_init(denali);
1475
1476	/*
1477	 * denali_isr register is done after all the hardware
1478	 * initilization is finished
1479	 */
1480	if (request_irq(denali->irq, denali_isr, IRQF_SHARED,
1481			DENALI_NAND_NAME, denali)) {
1482		pr_err("Spectra: Unable to allocate IRQ\n");
1483		return -ENODEV;
1484	}
1485
1486	/* now that our ISR is registered, we can enable interrupts */
1487	denali_set_intr_modes(denali, true);
1488	denali->mtd.name = "denali-nand";
1489	denali->mtd.owner = THIS_MODULE;
1490	denali->mtd.priv = &denali->nand;
1491
1492	/* register the driver with the NAND core subsystem */
1493	denali->nand.select_chip = denali_select_chip;
1494	denali->nand.cmdfunc = denali_cmdfunc;
1495	denali->nand.read_byte = denali_read_byte;
1496	denali->nand.waitfunc = denali_waitfunc;
1497
1498	/*
1499	 * scan for NAND devices attached to the controller
1500	 * this is the first stage in a two step process to register
1501	 * with the nand subsystem
1502	 */
1503	if (nand_scan_ident(&denali->mtd, denali->max_banks, NULL)) {
1504		ret = -ENXIO;
1505		goto failed_req_irq;
1506	}
1507
1508	/* allocate the right size buffer now */
1509	devm_kfree(denali->dev, denali->buf.buf);
1510	denali->buf.buf = devm_kzalloc(denali->dev,
1511			     denali->mtd.writesize + denali->mtd.oobsize,
1512			     GFP_KERNEL);
1513	if (!denali->buf.buf) {
1514		ret = -ENOMEM;
1515		goto failed_req_irq;
1516	}
1517
1518	/* Is 32-bit DMA supported? */
1519	ret = dma_set_mask(denali->dev, DMA_BIT_MASK(32));
1520	if (ret) {
1521		pr_err("Spectra: no usable DMA configuration\n");
1522		goto failed_req_irq;
1523	}
1524
1525	denali->buf.dma_buf = dma_map_single(denali->dev, denali->buf.buf,
1526			     denali->mtd.writesize + denali->mtd.oobsize,
1527			     DMA_BIDIRECTIONAL);
1528	if (dma_mapping_error(denali->dev, denali->buf.dma_buf)) {
1529		dev_err(denali->dev, "Spectra: failed to map DMA buffer\n");
1530		ret = -EIO;
1531		goto failed_req_irq;
1532	}
1533
1534	/*
1535	 * support for multi nand
1536	 * MTD known nothing about multi nand, so we should tell it
1537	 * the real pagesize and anything necessery
1538	 */
1539	denali->devnum = ioread32(denali->flash_reg + DEVICES_CONNECTED);
1540	denali->nand.chipsize <<= (denali->devnum - 1);
1541	denali->nand.page_shift += (denali->devnum - 1);
1542	denali->nand.pagemask = (denali->nand.chipsize >>
1543						denali->nand.page_shift) - 1;
1544	denali->nand.bbt_erase_shift += (denali->devnum - 1);
1545	denali->nand.phys_erase_shift = denali->nand.bbt_erase_shift;
1546	denali->nand.chip_shift += (denali->devnum - 1);
1547	denali->mtd.writesize <<= (denali->devnum - 1);
1548	denali->mtd.oobsize <<= (denali->devnum - 1);
1549	denali->mtd.erasesize <<= (denali->devnum - 1);
1550	denali->mtd.size = denali->nand.numchips * denali->nand.chipsize;
1551	denali->bbtskipbytes *= denali->devnum;
1552
1553	/*
1554	 * second stage of the NAND scan
1555	 * this stage requires information regarding ECC and
1556	 * bad block management.
1557	 */
1558
1559	/* Bad block management */
1560	denali->nand.bbt_td = &bbt_main_descr;
1561	denali->nand.bbt_md = &bbt_mirror_descr;
1562
1563	/* skip the scan for now until we have OOB read and write support */
1564	denali->nand.bbt_options |= NAND_BBT_USE_FLASH;
1565	denali->nand.options |= NAND_SKIP_BBTSCAN;
1566	denali->nand.ecc.mode = NAND_ECC_HW_SYNDROME;
1567
1568	/*
1569	 * Denali Controller only support 15bit and 8bit ECC in MRST,
1570	 * so just let controller do 15bit ECC for MLC and 8bit ECC for
1571	 * SLC if possible.
1572	 * */
1573	if (!nand_is_slc(&denali->nand) &&
1574			(denali->mtd.oobsize > (denali->bbtskipbytes +
1575			ECC_15BITS * (denali->mtd.writesize /
1576			ECC_SECTOR_SIZE)))) {
1577		/* if MLC OOB size is large enough, use 15bit ECC*/
1578		denali->nand.ecc.strength = 15;
1579		denali->nand.ecc.layout = &nand_15bit_oob;
1580		denali->nand.ecc.bytes = ECC_15BITS;
1581		iowrite32(15, denali->flash_reg + ECC_CORRECTION);
1582	} else if (denali->mtd.oobsize < (denali->bbtskipbytes +
1583			ECC_8BITS * (denali->mtd.writesize /
1584			ECC_SECTOR_SIZE))) {
1585		pr_err("Your NAND chip OOB is not large enough to contain 8bit ECC correction codes");
1586		goto failed_req_irq;
1587	} else {
1588		denali->nand.ecc.strength = 8;
1589		denali->nand.ecc.layout = &nand_8bit_oob;
1590		denali->nand.ecc.bytes = ECC_8BITS;
1591		iowrite32(8, denali->flash_reg + ECC_CORRECTION);
1592	}
1593
1594	denali->nand.ecc.bytes *= denali->devnum;
1595	denali->nand.ecc.strength *= denali->devnum;
1596	denali->nand.ecc.layout->eccbytes *=
1597		denali->mtd.writesize / ECC_SECTOR_SIZE;
1598	denali->nand.ecc.layout->oobfree[0].offset =
1599		denali->bbtskipbytes + denali->nand.ecc.layout->eccbytes;
1600	denali->nand.ecc.layout->oobfree[0].length =
1601		denali->mtd.oobsize - denali->nand.ecc.layout->eccbytes -
1602		denali->bbtskipbytes;
1603
1604	/*
1605	 * Let driver know the total blocks number and how many blocks
1606	 * contained by each nand chip. blksperchip will help driver to
1607	 * know how many blocks is taken by FW.
1608	 */
1609	denali->totalblks = denali->mtd.size >> denali->nand.phys_erase_shift;
1610	denali->blksperchip = denali->totalblks / denali->nand.numchips;
1611
1612	/*
1613	 * These functions are required by the NAND core framework, otherwise,
1614	 * the NAND core will assert. However, we don't need them, so we'll stub
1615	 * them out.
1616	 */
1617	denali->nand.ecc.calculate = denali_ecc_calculate;
1618	denali->nand.ecc.correct = denali_ecc_correct;
1619	denali->nand.ecc.hwctl = denali_ecc_hwctl;
1620
1621	/* override the default read operations */
1622	denali->nand.ecc.size = ECC_SECTOR_SIZE * denali->devnum;
1623	denali->nand.ecc.read_page = denali_read_page;
1624	denali->nand.ecc.read_page_raw = denali_read_page_raw;
1625	denali->nand.ecc.write_page = denali_write_page;
1626	denali->nand.ecc.write_page_raw = denali_write_page_raw;
1627	denali->nand.ecc.read_oob = denali_read_oob;
1628	denali->nand.ecc.write_oob = denali_write_oob;
1629	denali->nand.erase = denali_erase;
1630
1631	if (nand_scan_tail(&denali->mtd)) {
1632		ret = -ENXIO;
1633		goto failed_req_irq;
1634	}
1635
1636	ret = mtd_device_register(&denali->mtd, NULL, 0);
1637	if (ret) {
1638		dev_err(denali->dev, "Spectra: Failed to register MTD: %d\n",
1639				ret);
1640		goto failed_req_irq;
1641	}
1642	return 0;
1643
1644failed_req_irq:
1645	denali_irq_cleanup(denali->irq, denali);
1646
1647	return ret;
1648}
1649EXPORT_SYMBOL(denali_init);
1650
1651/* driver exit point */
1652void denali_remove(struct denali_nand_info *denali)
1653{
1654	denali_irq_cleanup(denali->irq, denali);
1655	dma_unmap_single(denali->dev, denali->buf.dma_buf,
1656			 denali->mtd.writesize + denali->mtd.oobsize,
1657			 DMA_BIDIRECTIONAL);
1658}
1659EXPORT_SYMBOL(denali_remove);
1660