1 /*
2  * Common Flash Interface support:
3  *   AMD & Fujitsu Standard Vendor Command Set (ID 0x0002)
4  *
5  * Copyright (C) 2000 Crossnet Co. <info@crossnet.co.jp>
6  * Copyright (C) 2004 Arcom Control Systems Ltd <linux@arcom.com>
7  * Copyright (C) 2005 MontaVista Software Inc. <source@mvista.com>
8  *
9  * 2_by_8 routines added by Simon Munton
10  *
11  * 4_by_16 work by Carolyn J. Smith
12  *
13  * XIP support hooks by Vitaly Wool (based on code for Intel flash
14  * by Nicolas Pitre)
15  *
16  * 25/09/2008 Christopher Moore: TopBottom fixup for many Macronix with CFI V1.0
17  *
18  * Occasionally maintained by Thayne Harbaugh tharbaugh at lnxi dot com
19  *
20  * This code is GPL
21  */
22 
23 #include <linux/module.h>
24 #include <linux/types.h>
25 #include <linux/kernel.h>
26 #include <linux/sched.h>
27 #include <asm/io.h>
28 #include <asm/byteorder.h>
29 
30 #include <linux/errno.h>
31 #include <linux/slab.h>
32 #include <linux/delay.h>
33 #include <linux/interrupt.h>
34 #include <linux/reboot.h>
35 #include <linux/of.h>
36 #include <linux/of_platform.h>
37 #include <linux/mtd/map.h>
38 #include <linux/mtd/mtd.h>
39 #include <linux/mtd/cfi.h>
40 #include <linux/mtd/xip.h>
41 
42 #define AMD_BOOTLOC_BUG
43 #define FORCE_WORD_WRITE 0
44 
45 #define MAX_RETRIES 3
46 
47 #define SST49LF004B		0x0060
48 #define SST49LF040B		0x0050
49 #define SST49LF008A		0x005a
50 #define AT49BV6416		0x00d6
51 
52 /*
53  * Status Register bit description. Used by flash devices that don't
54  * support DQ polling (e.g. HyperFlash)
55  */
56 #define CFI_SR_DRB		BIT(7)
57 #define CFI_SR_ESB		BIT(5)
58 #define CFI_SR_PSB		BIT(4)
59 #define CFI_SR_WBASB		BIT(3)
60 #define CFI_SR_SLSB		BIT(1)
61 
62 static int cfi_amdstd_read (struct mtd_info *, loff_t, size_t, size_t *, u_char *);
63 static int cfi_amdstd_write_words(struct mtd_info *, loff_t, size_t, size_t *, const u_char *);
64 #if !FORCE_WORD_WRITE
65 static int cfi_amdstd_write_buffers(struct mtd_info *, loff_t, size_t, size_t *, const u_char *);
66 #endif
67 static int cfi_amdstd_erase_chip(struct mtd_info *, struct erase_info *);
68 static int cfi_amdstd_erase_varsize(struct mtd_info *, struct erase_info *);
69 static void cfi_amdstd_sync (struct mtd_info *);
70 static int cfi_amdstd_suspend (struct mtd_info *);
71 static void cfi_amdstd_resume (struct mtd_info *);
72 static int cfi_amdstd_reboot(struct notifier_block *, unsigned long, void *);
73 static int cfi_amdstd_get_fact_prot_info(struct mtd_info *, size_t,
74 					 size_t *, struct otp_info *);
75 static int cfi_amdstd_get_user_prot_info(struct mtd_info *, size_t,
76 					 size_t *, struct otp_info *);
77 static int cfi_amdstd_secsi_read (struct mtd_info *, loff_t, size_t, size_t *, u_char *);
78 static int cfi_amdstd_read_fact_prot_reg(struct mtd_info *, loff_t, size_t,
79 					 size_t *, u_char *);
80 static int cfi_amdstd_read_user_prot_reg(struct mtd_info *, loff_t, size_t,
81 					 size_t *, u_char *);
82 static int cfi_amdstd_write_user_prot_reg(struct mtd_info *, loff_t, size_t,
83 					  size_t *, const u_char *);
84 static int cfi_amdstd_lock_user_prot_reg(struct mtd_info *, loff_t, size_t);
85 
86 static int cfi_amdstd_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
87 				  size_t *retlen, const u_char *buf);
88 
89 static void cfi_amdstd_destroy(struct mtd_info *);
90 
91 struct mtd_info *cfi_cmdset_0002(struct map_info *, int);
92 static struct mtd_info *cfi_amdstd_setup (struct mtd_info *);
93 
94 static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr, int mode);
95 static void put_chip(struct map_info *map, struct flchip *chip, unsigned long adr);
96 #include "fwh_lock.h"
97 
98 static int cfi_atmel_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
99 static int cfi_atmel_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
100 
101 static int cfi_ppb_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
102 static int cfi_ppb_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
103 static int cfi_ppb_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len);
104 
105 static struct mtd_chip_driver cfi_amdstd_chipdrv = {
106 	.probe		= NULL, /* Not usable directly */
107 	.destroy	= cfi_amdstd_destroy,
108 	.name		= "cfi_cmdset_0002",
109 	.module		= THIS_MODULE
110 };
111 
112 /*
113  * Use status register to poll for Erase/write completion when DQ is not
114  * supported. This is indicated by Bit[1:0] of SoftwareFeatures field in
115  * CFI Primary Vendor-Specific Extended Query table 1.5
116  */
117 static int cfi_use_status_reg(struct cfi_private *cfi)
118 {
119 	struct cfi_pri_amdstd *extp = cfi->cmdset_priv;
120 	u8 poll_mask = CFI_POLL_STATUS_REG | CFI_POLL_DQ;
121 
122 	return extp && extp->MinorVersion >= '5' &&
123 		(extp->SoftwareFeatures & poll_mask) == CFI_POLL_STATUS_REG;
124 }
125 
126 static int cfi_check_err_status(struct map_info *map, struct flchip *chip,
127 				unsigned long adr)
128 {
129 	struct cfi_private *cfi = map->fldrv_priv;
130 	map_word status;
131 
132 	if (!cfi_use_status_reg(cfi))
133 		return 0;
134 
135 	cfi_send_gen_cmd(0x70, cfi->addr_unlock1, chip->start, map, cfi,
136 			 cfi->device_type, NULL);
137 	status = map_read(map, adr);
138 
139 	/* The error bits are invalid while the chip's busy */
140 	if (!map_word_bitsset(map, status, CMD(CFI_SR_DRB)))
141 		return 0;
142 
143 	if (map_word_bitsset(map, status, CMD(0x3a))) {
144 		unsigned long chipstatus = MERGESTATUS(status);
145 
146 		if (chipstatus & CFI_SR_ESB)
147 			pr_err("%s erase operation failed, status %lx\n",
148 			       map->name, chipstatus);
149 		if (chipstatus & CFI_SR_PSB)
150 			pr_err("%s program operation failed, status %lx\n",
151 			       map->name, chipstatus);
152 		if (chipstatus & CFI_SR_WBASB)
153 			pr_err("%s buffer program command aborted, status %lx\n",
154 			       map->name, chipstatus);
155 		if (chipstatus & CFI_SR_SLSB)
156 			pr_err("%s sector write protected, status %lx\n",
157 			       map->name, chipstatus);
158 
159 		/* Erase/Program status bits are set on the operation failure */
160 		if (chipstatus & (CFI_SR_ESB | CFI_SR_PSB))
161 			return 1;
162 	}
163 	return 0;
164 }
165 
166 /* #define DEBUG_CFI_FEATURES */
167 
168 
169 #ifdef DEBUG_CFI_FEATURES
170 static void cfi_tell_features(struct cfi_pri_amdstd *extp)
171 {
172 	const char* erase_suspend[3] = {
173 		"Not supported", "Read only", "Read/write"
174 	};
175 	const char* top_bottom[6] = {
176 		"No WP", "8x8KiB sectors at top & bottom, no WP",
177 		"Bottom boot", "Top boot",
178 		"Uniform, Bottom WP", "Uniform, Top WP"
179 	};
180 
181 	printk("  Silicon revision: %d\n", extp->SiliconRevision >> 1);
182 	printk("  Address sensitive unlock: %s\n",
183 	       (extp->SiliconRevision & 1) ? "Not required" : "Required");
184 
185 	if (extp->EraseSuspend < ARRAY_SIZE(erase_suspend))
186 		printk("  Erase Suspend: %s\n", erase_suspend[extp->EraseSuspend]);
187 	else
188 		printk("  Erase Suspend: Unknown value %d\n", extp->EraseSuspend);
189 
190 	if (extp->BlkProt == 0)
191 		printk("  Block protection: Not supported\n");
192 	else
193 		printk("  Block protection: %d sectors per group\n", extp->BlkProt);
194 
195 
196 	printk("  Temporary block unprotect: %s\n",
197 	       extp->TmpBlkUnprotect ? "Supported" : "Not supported");
198 	printk("  Block protect/unprotect scheme: %d\n", extp->BlkProtUnprot);
199 	printk("  Number of simultaneous operations: %d\n", extp->SimultaneousOps);
200 	printk("  Burst mode: %s\n",
201 	       extp->BurstMode ? "Supported" : "Not supported");
202 	if (extp->PageMode == 0)
203 		printk("  Page mode: Not supported\n");
204 	else
205 		printk("  Page mode: %d word page\n", extp->PageMode << 2);
206 
207 	printk("  Vpp Supply Minimum Program/Erase Voltage: %d.%d V\n",
208 	       extp->VppMin >> 4, extp->VppMin & 0xf);
209 	printk("  Vpp Supply Maximum Program/Erase Voltage: %d.%d V\n",
210 	       extp->VppMax >> 4, extp->VppMax & 0xf);
211 
212 	if (extp->TopBottom < ARRAY_SIZE(top_bottom))
213 		printk("  Top/Bottom Boot Block: %s\n", top_bottom[extp->TopBottom]);
214 	else
215 		printk("  Top/Bottom Boot Block: Unknown value %d\n", extp->TopBottom);
216 }
217 #endif
218 
219 #ifdef AMD_BOOTLOC_BUG
220 /* Wheee. Bring me the head of someone at AMD. */
221 static void fixup_amd_bootblock(struct mtd_info *mtd)
222 {
223 	struct map_info *map = mtd->priv;
224 	struct cfi_private *cfi = map->fldrv_priv;
225 	struct cfi_pri_amdstd *extp = cfi->cmdset_priv;
226 	__u8 major = extp->MajorVersion;
227 	__u8 minor = extp->MinorVersion;
228 
229 	if (((major << 8) | minor) < 0x3131) {
230 		/* CFI version 1.0 => don't trust bootloc */
231 
232 		pr_debug("%s: JEDEC Vendor ID is 0x%02X Device ID is 0x%02X\n",
233 			map->name, cfi->mfr, cfi->id);
234 
235 		/* AFAICS all 29LV400 with a bottom boot block have a device ID
236 		 * of 0x22BA in 16-bit mode and 0xBA in 8-bit mode.
237 		 * These were badly detected as they have the 0x80 bit set
238 		 * so treat them as a special case.
239 		 */
240 		if (((cfi->id == 0xBA) || (cfi->id == 0x22BA)) &&
241 
242 			/* Macronix added CFI to their 2nd generation
243 			 * MX29LV400C B/T but AFAICS no other 29LV400 (AMD,
244 			 * Fujitsu, Spansion, EON, ESI and older Macronix)
245 			 * has CFI.
246 			 *
247 			 * Therefore also check the manufacturer.
248 			 * This reduces the risk of false detection due to
249 			 * the 8-bit device ID.
250 			 */
251 			(cfi->mfr == CFI_MFR_MACRONIX)) {
252 			pr_debug("%s: Macronix MX29LV400C with bottom boot block"
253 				" detected\n", map->name);
254 			extp->TopBottom = 2;	/* bottom boot */
255 		} else
256 		if (cfi->id & 0x80) {
257 			printk(KERN_WARNING "%s: JEDEC Device ID is 0x%02X. Assuming broken CFI table.\n", map->name, cfi->id);
258 			extp->TopBottom = 3;	/* top boot */
259 		} else {
260 			extp->TopBottom = 2;	/* bottom boot */
261 		}
262 
263 		pr_debug("%s: AMD CFI PRI V%c.%c has no boot block field;"
264 			" deduced %s from Device ID\n", map->name, major, minor,
265 			extp->TopBottom == 2 ? "bottom" : "top");
266 	}
267 }
268 #endif
269 
270 #if !FORCE_WORD_WRITE
271 static void fixup_use_write_buffers(struct mtd_info *mtd)
272 {
273 	struct map_info *map = mtd->priv;
274 	struct cfi_private *cfi = map->fldrv_priv;
275 
276 	if (cfi->mfr == CFI_MFR_AMD && cfi->id == 0x2201)
277 		return;
278 
279 	if (cfi->cfiq->BufWriteTimeoutTyp) {
280 		pr_debug("Using buffer write method\n");
281 		mtd->_write = cfi_amdstd_write_buffers;
282 	}
283 }
284 #endif /* !FORCE_WORD_WRITE */
285 
286 /* Atmel chips don't use the same PRI format as AMD chips */
287 static void fixup_convert_atmel_pri(struct mtd_info *mtd)
288 {
289 	struct map_info *map = mtd->priv;
290 	struct cfi_private *cfi = map->fldrv_priv;
291 	struct cfi_pri_amdstd *extp = cfi->cmdset_priv;
292 	struct cfi_pri_atmel atmel_pri;
293 
294 	memcpy(&atmel_pri, extp, sizeof(atmel_pri));
295 	memset((char *)extp + 5, 0, sizeof(*extp) - 5);
296 
297 	if (atmel_pri.Features & 0x02)
298 		extp->EraseSuspend = 2;
299 
300 	/* Some chips got it backwards... */
301 	if (cfi->id == AT49BV6416) {
302 		if (atmel_pri.BottomBoot)
303 			extp->TopBottom = 3;
304 		else
305 			extp->TopBottom = 2;
306 	} else {
307 		if (atmel_pri.BottomBoot)
308 			extp->TopBottom = 2;
309 		else
310 			extp->TopBottom = 3;
311 	}
312 
313 	/* burst write mode not supported */
314 	cfi->cfiq->BufWriteTimeoutTyp = 0;
315 	cfi->cfiq->BufWriteTimeoutMax = 0;
316 }
317 
318 static void fixup_use_secsi(struct mtd_info *mtd)
319 {
320 	/* Setup for chips with a secsi area */
321 	mtd->_read_user_prot_reg = cfi_amdstd_secsi_read;
322 	mtd->_read_fact_prot_reg = cfi_amdstd_secsi_read;
323 }
324 
325 static void fixup_use_erase_chip(struct mtd_info *mtd)
326 {
327 	struct map_info *map = mtd->priv;
328 	struct cfi_private *cfi = map->fldrv_priv;
329 	if ((cfi->cfiq->NumEraseRegions == 1) &&
330 		((cfi->cfiq->EraseRegionInfo[0] & 0xffff) == 0)) {
331 		mtd->_erase = cfi_amdstd_erase_chip;
332 	}
333 
334 }
335 
336 /*
337  * Some Atmel chips (e.g. the AT49BV6416) power-up with all sectors
338  * locked by default.
339  */
340 static void fixup_use_atmel_lock(struct mtd_info *mtd)
341 {
342 	mtd->_lock = cfi_atmel_lock;
343 	mtd->_unlock = cfi_atmel_unlock;
344 	mtd->flags |= MTD_POWERUP_LOCK;
345 }
346 
347 static void fixup_old_sst_eraseregion(struct mtd_info *mtd)
348 {
349 	struct map_info *map = mtd->priv;
350 	struct cfi_private *cfi = map->fldrv_priv;
351 
352 	/*
353 	 * These flashes report two separate eraseblock regions based on the
354 	 * sector_erase-size and block_erase-size, although they both operate on the
355 	 * same memory. This is not allowed according to CFI, so we just pick the
356 	 * sector_erase-size.
357 	 */
358 	cfi->cfiq->NumEraseRegions = 1;
359 }
360 
361 static void fixup_sst39vf(struct mtd_info *mtd)
362 {
363 	struct map_info *map = mtd->priv;
364 	struct cfi_private *cfi = map->fldrv_priv;
365 
366 	fixup_old_sst_eraseregion(mtd);
367 
368 	cfi->addr_unlock1 = 0x5555;
369 	cfi->addr_unlock2 = 0x2AAA;
370 }
371 
372 static void fixup_sst39vf_rev_b(struct mtd_info *mtd)
373 {
374 	struct map_info *map = mtd->priv;
375 	struct cfi_private *cfi = map->fldrv_priv;
376 
377 	fixup_old_sst_eraseregion(mtd);
378 
379 	cfi->addr_unlock1 = 0x555;
380 	cfi->addr_unlock2 = 0x2AA;
381 
382 	cfi->sector_erase_cmd = CMD(0x50);
383 }
384 
385 static void fixup_sst38vf640x_sectorsize(struct mtd_info *mtd)
386 {
387 	struct map_info *map = mtd->priv;
388 	struct cfi_private *cfi = map->fldrv_priv;
389 
390 	fixup_sst39vf_rev_b(mtd);
391 
392 	/*
393 	 * CFI reports 1024 sectors (0x03ff+1) of 64KBytes (0x0100*256) where
394 	 * it should report a size of 8KBytes (0x0020*256).
395 	 */
396 	cfi->cfiq->EraseRegionInfo[0] = 0x002003ff;
397 	pr_warn("%s: Bad 38VF640x CFI data; adjusting sector size from 64 to 8KiB\n",
398 		mtd->name);
399 }
400 
401 static void fixup_s29gl064n_sectors(struct mtd_info *mtd)
402 {
403 	struct map_info *map = mtd->priv;
404 	struct cfi_private *cfi = map->fldrv_priv;
405 
406 	if ((cfi->cfiq->EraseRegionInfo[0] & 0xffff) == 0x003f) {
407 		cfi->cfiq->EraseRegionInfo[0] |= 0x0040;
408 		pr_warn("%s: Bad S29GL064N CFI data; adjust from 64 to 128 sectors\n",
409 			mtd->name);
410 	}
411 }
412 
413 static void fixup_s29gl032n_sectors(struct mtd_info *mtd)
414 {
415 	struct map_info *map = mtd->priv;
416 	struct cfi_private *cfi = map->fldrv_priv;
417 
418 	if ((cfi->cfiq->EraseRegionInfo[1] & 0xffff) == 0x007e) {
419 		cfi->cfiq->EraseRegionInfo[1] &= ~0x0040;
420 		pr_warn("%s: Bad S29GL032N CFI data; adjust from 127 to 63 sectors\n",
421 			mtd->name);
422 	}
423 }
424 
425 static void fixup_s29ns512p_sectors(struct mtd_info *mtd)
426 {
427 	struct map_info *map = mtd->priv;
428 	struct cfi_private *cfi = map->fldrv_priv;
429 
430 	/*
431 	 *  S29NS512P flash uses more than 8bits to report number of sectors,
432 	 * which is not permitted by CFI.
433 	 */
434 	cfi->cfiq->EraseRegionInfo[0] = 0x020001ff;
435 	pr_warn("%s: Bad S29NS512P CFI data; adjust to 512 sectors\n",
436 		mtd->name);
437 }
438 
439 /* Used to fix CFI-Tables of chips without Extended Query Tables */
440 static struct cfi_fixup cfi_nopri_fixup_table[] = {
441 	{ CFI_MFR_SST, 0x234a, fixup_sst39vf }, /* SST39VF1602 */
442 	{ CFI_MFR_SST, 0x234b, fixup_sst39vf }, /* SST39VF1601 */
443 	{ CFI_MFR_SST, 0x235a, fixup_sst39vf }, /* SST39VF3202 */
444 	{ CFI_MFR_SST, 0x235b, fixup_sst39vf }, /* SST39VF3201 */
445 	{ CFI_MFR_SST, 0x235c, fixup_sst39vf_rev_b }, /* SST39VF3202B */
446 	{ CFI_MFR_SST, 0x235d, fixup_sst39vf_rev_b }, /* SST39VF3201B */
447 	{ CFI_MFR_SST, 0x236c, fixup_sst39vf_rev_b }, /* SST39VF6402B */
448 	{ CFI_MFR_SST, 0x236d, fixup_sst39vf_rev_b }, /* SST39VF6401B */
449 	{ 0, 0, NULL }
450 };
451 
452 static struct cfi_fixup cfi_fixup_table[] = {
453 	{ CFI_MFR_ATMEL, CFI_ID_ANY, fixup_convert_atmel_pri },
454 #ifdef AMD_BOOTLOC_BUG
455 	{ CFI_MFR_AMD, CFI_ID_ANY, fixup_amd_bootblock },
456 	{ CFI_MFR_AMIC, CFI_ID_ANY, fixup_amd_bootblock },
457 	{ CFI_MFR_MACRONIX, CFI_ID_ANY, fixup_amd_bootblock },
458 #endif
459 	{ CFI_MFR_AMD, 0x0050, fixup_use_secsi },
460 	{ CFI_MFR_AMD, 0x0053, fixup_use_secsi },
461 	{ CFI_MFR_AMD, 0x0055, fixup_use_secsi },
462 	{ CFI_MFR_AMD, 0x0056, fixup_use_secsi },
463 	{ CFI_MFR_AMD, 0x005C, fixup_use_secsi },
464 	{ CFI_MFR_AMD, 0x005F, fixup_use_secsi },
465 	{ CFI_MFR_AMD, 0x0c01, fixup_s29gl064n_sectors },
466 	{ CFI_MFR_AMD, 0x1301, fixup_s29gl064n_sectors },
467 	{ CFI_MFR_AMD, 0x1a00, fixup_s29gl032n_sectors },
468 	{ CFI_MFR_AMD, 0x1a01, fixup_s29gl032n_sectors },
469 	{ CFI_MFR_AMD, 0x3f00, fixup_s29ns512p_sectors },
470 	{ CFI_MFR_SST, 0x536a, fixup_sst38vf640x_sectorsize }, /* SST38VF6402 */
471 	{ CFI_MFR_SST, 0x536b, fixup_sst38vf640x_sectorsize }, /* SST38VF6401 */
472 	{ CFI_MFR_SST, 0x536c, fixup_sst38vf640x_sectorsize }, /* SST38VF6404 */
473 	{ CFI_MFR_SST, 0x536d, fixup_sst38vf640x_sectorsize }, /* SST38VF6403 */
474 #if !FORCE_WORD_WRITE
475 	{ CFI_MFR_ANY, CFI_ID_ANY, fixup_use_write_buffers },
476 #endif
477 	{ 0, 0, NULL }
478 };
479 static struct cfi_fixup jedec_fixup_table[] = {
480 	{ CFI_MFR_SST, SST49LF004B, fixup_use_fwh_lock },
481 	{ CFI_MFR_SST, SST49LF040B, fixup_use_fwh_lock },
482 	{ CFI_MFR_SST, SST49LF008A, fixup_use_fwh_lock },
483 	{ 0, 0, NULL }
484 };
485 
486 static struct cfi_fixup fixup_table[] = {
487 	/* The CFI vendor ids and the JEDEC vendor IDs appear
488 	 * to be common.  It is like the devices id's are as
489 	 * well.  This table is to pick all cases where
490 	 * we know that is the case.
491 	 */
492 	{ CFI_MFR_ANY, CFI_ID_ANY, fixup_use_erase_chip },
493 	{ CFI_MFR_ATMEL, AT49BV6416, fixup_use_atmel_lock },
494 	{ 0, 0, NULL }
495 };
496 
497 
498 static void cfi_fixup_major_minor(struct cfi_private *cfi,
499 				  struct cfi_pri_amdstd *extp)
500 {
501 	if (cfi->mfr == CFI_MFR_SAMSUNG) {
502 		if ((extp->MajorVersion == '0' && extp->MinorVersion == '0') ||
503 		    (extp->MajorVersion == '3' && extp->MinorVersion == '3')) {
504 			/*
505 			 * Samsung K8P2815UQB and K8D6x16UxM chips
506 			 * report major=0 / minor=0.
507 			 * K8D3x16UxC chips report major=3 / minor=3.
508 			 */
509 			printk(KERN_NOTICE "  Fixing Samsung's Amd/Fujitsu"
510 			       " Extended Query version to 1.%c\n",
511 			       extp->MinorVersion);
512 			extp->MajorVersion = '1';
513 		}
514 	}
515 
516 	/*
517 	 * SST 38VF640x chips report major=0xFF / minor=0xFF.
518 	 */
519 	if (cfi->mfr == CFI_MFR_SST && (cfi->id >> 4) == 0x0536) {
520 		extp->MajorVersion = '1';
521 		extp->MinorVersion = '0';
522 	}
523 }
524 
525 static int is_m29ew(struct cfi_private *cfi)
526 {
527 	if (cfi->mfr == CFI_MFR_INTEL &&
528 	    ((cfi->device_type == CFI_DEVICETYPE_X8 && (cfi->id & 0xff) == 0x7e) ||
529 	     (cfi->device_type == CFI_DEVICETYPE_X16 && cfi->id == 0x227e)))
530 		return 1;
531 	return 0;
532 }
533 
534 /*
535  * From TN-13-07: Patching the Linux Kernel and U-Boot for M29 Flash, page 20:
536  * Some revisions of the M29EW suffer from erase suspend hang ups. In
537  * particular, it can occur when the sequence
538  * Erase Confirm -> Suspend -> Program -> Resume
539  * causes a lockup due to internal timing issues. The consequence is that the
540  * erase cannot be resumed without inserting a dummy command after programming
541  * and prior to resuming. [...] The work-around is to issue a dummy write cycle
542  * that writes an F0 command code before the RESUME command.
543  */
544 static void cfi_fixup_m29ew_erase_suspend(struct map_info *map,
545 					  unsigned long adr)
546 {
547 	struct cfi_private *cfi = map->fldrv_priv;
548 	/* before resume, insert a dummy 0xF0 cycle for Micron M29EW devices */
549 	if (is_m29ew(cfi))
550 		map_write(map, CMD(0xF0), adr);
551 }
552 
553 /*
554  * From TN-13-07: Patching the Linux Kernel and U-Boot for M29 Flash, page 22:
555  *
556  * Some revisions of the M29EW (for example, A1 and A2 step revisions)
557  * are affected by a problem that could cause a hang up when an ERASE SUSPEND
558  * command is issued after an ERASE RESUME operation without waiting for a
559  * minimum delay.  The result is that once the ERASE seems to be completed
560  * (no bits are toggling), the contents of the Flash memory block on which
561  * the erase was ongoing could be inconsistent with the expected values
562  * (typically, the array value is stuck to the 0xC0, 0xC4, 0x80, or 0x84
563  * values), causing a consequent failure of the ERASE operation.
564  * The occurrence of this issue could be high, especially when file system
565  * operations on the Flash are intensive.  As a result, it is recommended
566  * that a patch be applied.  Intensive file system operations can cause many
567  * calls to the garbage routine to free Flash space (also by erasing physical
568  * Flash blocks) and as a result, many consecutive SUSPEND and RESUME
569  * commands can occur.  The problem disappears when a delay is inserted after
570  * the RESUME command by using the udelay() function available in Linux.
571  * The DELAY value must be tuned based on the customer's platform.
572  * The maximum value that fixes the problem in all cases is 500us.
573  * But, in our experience, a delay of 30 µs to 50 µs is sufficient
574  * in most cases.
575  * We have chosen 500µs because this latency is acceptable.
576  */
577 static void cfi_fixup_m29ew_delay_after_resume(struct cfi_private *cfi)
578 {
579 	/*
580 	 * Resolving the Delay After Resume Issue see Micron TN-13-07
581 	 * Worst case delay must be 500µs but 30-50µs should be ok as well
582 	 */
583 	if (is_m29ew(cfi))
584 		cfi_udelay(500);
585 }
586 
587 struct mtd_info *cfi_cmdset_0002(struct map_info *map, int primary)
588 {
589 	struct cfi_private *cfi = map->fldrv_priv;
590 	struct device_node __maybe_unused *np = map->device_node;
591 	struct mtd_info *mtd;
592 	int i;
593 
594 	mtd = kzalloc(sizeof(*mtd), GFP_KERNEL);
595 	if (!mtd)
596 		return NULL;
597 	mtd->priv = map;
598 	mtd->type = MTD_NORFLASH;
599 
600 	/* Fill in the default mtd operations */
601 	mtd->_erase   = cfi_amdstd_erase_varsize;
602 	mtd->_write   = cfi_amdstd_write_words;
603 	mtd->_read    = cfi_amdstd_read;
604 	mtd->_sync    = cfi_amdstd_sync;
605 	mtd->_suspend = cfi_amdstd_suspend;
606 	mtd->_resume  = cfi_amdstd_resume;
607 	mtd->_read_user_prot_reg = cfi_amdstd_read_user_prot_reg;
608 	mtd->_read_fact_prot_reg = cfi_amdstd_read_fact_prot_reg;
609 	mtd->_get_fact_prot_info = cfi_amdstd_get_fact_prot_info;
610 	mtd->_get_user_prot_info = cfi_amdstd_get_user_prot_info;
611 	mtd->_write_user_prot_reg = cfi_amdstd_write_user_prot_reg;
612 	mtd->_lock_user_prot_reg = cfi_amdstd_lock_user_prot_reg;
613 	mtd->flags   = MTD_CAP_NORFLASH;
614 	mtd->name    = map->name;
615 	mtd->writesize = 1;
616 	mtd->writebufsize = cfi_interleave(cfi) << cfi->cfiq->MaxBufWriteSize;
617 
618 	pr_debug("MTD %s(): write buffer size %d\n", __func__,
619 			mtd->writebufsize);
620 
621 	mtd->_panic_write = cfi_amdstd_panic_write;
622 	mtd->reboot_notifier.notifier_call = cfi_amdstd_reboot;
623 
624 	if (cfi->cfi_mode==CFI_MODE_CFI){
625 		unsigned char bootloc;
626 		__u16 adr = primary?cfi->cfiq->P_ADR:cfi->cfiq->A_ADR;
627 		struct cfi_pri_amdstd *extp;
628 
629 		extp = (struct cfi_pri_amdstd*)cfi_read_pri(map, adr, sizeof(*extp), "Amd/Fujitsu");
630 		if (extp) {
631 			/*
632 			 * It's a real CFI chip, not one for which the probe
633 			 * routine faked a CFI structure.
634 			 */
635 			cfi_fixup_major_minor(cfi, extp);
636 
637 			/*
638 			 * Valid primary extension versions are: 1.0, 1.1, 1.2, 1.3, 1.4, 1.5
639 			 * see: http://cs.ozerki.net/zap/pub/axim-x5/docs/cfi_r20.pdf, page 19
640 			 *      http://www.spansion.com/Support/AppNotes/cfi_100_20011201.pdf
641 			 *      http://www.spansion.com/Support/Datasheets/s29ws-p_00_a12_e.pdf
642 			 *      http://www.spansion.com/Support/Datasheets/S29GL_128S_01GS_00_02_e.pdf
643 			 */
644 			if (extp->MajorVersion != '1' ||
645 			    (extp->MajorVersion == '1' && (extp->MinorVersion < '0' || extp->MinorVersion > '5'))) {
646 				printk(KERN_ERR "  Unknown Amd/Fujitsu Extended Query "
647 				       "version %c.%c (%#02x/%#02x).\n",
648 				       extp->MajorVersion, extp->MinorVersion,
649 				       extp->MajorVersion, extp->MinorVersion);
650 				kfree(extp);
651 				kfree(mtd);
652 				return NULL;
653 			}
654 
655 			printk(KERN_INFO "  Amd/Fujitsu Extended Query version %c.%c.\n",
656 			       extp->MajorVersion, extp->MinorVersion);
657 
658 			/* Install our own private info structure */
659 			cfi->cmdset_priv = extp;
660 
661 			/* Apply cfi device specific fixups */
662 			cfi_fixup(mtd, cfi_fixup_table);
663 
664 #ifdef DEBUG_CFI_FEATURES
665 			/* Tell the user about it in lots of lovely detail */
666 			cfi_tell_features(extp);
667 #endif
668 
669 #ifdef CONFIG_OF
670 			if (np && of_property_read_bool(
671 				    np, "use-advanced-sector-protection")
672 			    && extp->BlkProtUnprot == 8) {
673 				printk(KERN_INFO "  Advanced Sector Protection (PPB Locking) supported\n");
674 				mtd->_lock = cfi_ppb_lock;
675 				mtd->_unlock = cfi_ppb_unlock;
676 				mtd->_is_locked = cfi_ppb_is_locked;
677 			}
678 #endif
679 
680 			bootloc = extp->TopBottom;
681 			if ((bootloc < 2) || (bootloc > 5)) {
682 				printk(KERN_WARNING "%s: CFI contains unrecognised boot "
683 				       "bank location (%d). Assuming bottom.\n",
684 				       map->name, bootloc);
685 				bootloc = 2;
686 			}
687 
688 			if (bootloc == 3 && cfi->cfiq->NumEraseRegions > 1) {
689 				printk(KERN_WARNING "%s: Swapping erase regions for top-boot CFI table.\n", map->name);
690 
691 				for (i=0; i<cfi->cfiq->NumEraseRegions / 2; i++) {
692 					int j = (cfi->cfiq->NumEraseRegions-1)-i;
693 
694 					swap(cfi->cfiq->EraseRegionInfo[i],
695 					     cfi->cfiq->EraseRegionInfo[j]);
696 				}
697 			}
698 			/* Set the default CFI lock/unlock addresses */
699 			cfi->addr_unlock1 = 0x555;
700 			cfi->addr_unlock2 = 0x2aa;
701 		}
702 		cfi_fixup(mtd, cfi_nopri_fixup_table);
703 
704 		if (!cfi->addr_unlock1 || !cfi->addr_unlock2) {
705 			kfree(mtd);
706 			return NULL;
707 		}
708 
709 	} /* CFI mode */
710 	else if (cfi->cfi_mode == CFI_MODE_JEDEC) {
711 		/* Apply jedec specific fixups */
712 		cfi_fixup(mtd, jedec_fixup_table);
713 	}
714 	/* Apply generic fixups */
715 	cfi_fixup(mtd, fixup_table);
716 
717 	for (i=0; i< cfi->numchips; i++) {
718 		cfi->chips[i].word_write_time = 1<<cfi->cfiq->WordWriteTimeoutTyp;
719 		cfi->chips[i].buffer_write_time = 1<<cfi->cfiq->BufWriteTimeoutTyp;
720 		cfi->chips[i].erase_time = 1<<cfi->cfiq->BlockEraseTimeoutTyp;
721 		/*
722 		 * First calculate the timeout max according to timeout field
723 		 * of struct cfi_ident that probed from chip's CFI aera, if
724 		 * available. Specify a minimum of 2000us, in case the CFI data
725 		 * is wrong.
726 		 */
727 		if (cfi->cfiq->BufWriteTimeoutTyp &&
728 		    cfi->cfiq->BufWriteTimeoutMax)
729 			cfi->chips[i].buffer_write_time_max =
730 				1 << (cfi->cfiq->BufWriteTimeoutTyp +
731 				      cfi->cfiq->BufWriteTimeoutMax);
732 		else
733 			cfi->chips[i].buffer_write_time_max = 0;
734 
735 		cfi->chips[i].buffer_write_time_max =
736 			max(cfi->chips[i].buffer_write_time_max, 2000);
737 
738 		cfi->chips[i].ref_point_counter = 0;
739 		init_waitqueue_head(&(cfi->chips[i].wq));
740 	}
741 
742 	map->fldrv = &cfi_amdstd_chipdrv;
743 
744 	return cfi_amdstd_setup(mtd);
745 }
746 struct mtd_info *cfi_cmdset_0006(struct map_info *map, int primary) __attribute__((alias("cfi_cmdset_0002")));
747 struct mtd_info *cfi_cmdset_0701(struct map_info *map, int primary) __attribute__((alias("cfi_cmdset_0002")));
748 EXPORT_SYMBOL_GPL(cfi_cmdset_0002);
749 EXPORT_SYMBOL_GPL(cfi_cmdset_0006);
750 EXPORT_SYMBOL_GPL(cfi_cmdset_0701);
751 
752 static struct mtd_info *cfi_amdstd_setup(struct mtd_info *mtd)
753 {
754 	struct map_info *map = mtd->priv;
755 	struct cfi_private *cfi = map->fldrv_priv;
756 	unsigned long devsize = (1<<cfi->cfiq->DevSize) * cfi->interleave;
757 	unsigned long offset = 0;
758 	int i,j;
759 
760 	printk(KERN_NOTICE "number of %s chips: %d\n",
761 	       (cfi->cfi_mode == CFI_MODE_CFI)?"CFI":"JEDEC",cfi->numchips);
762 	/* Select the correct geometry setup */
763 	mtd->size = devsize * cfi->numchips;
764 
765 	mtd->numeraseregions = cfi->cfiq->NumEraseRegions * cfi->numchips;
766 	mtd->eraseregions = kmalloc_array(mtd->numeraseregions,
767 					  sizeof(struct mtd_erase_region_info),
768 					  GFP_KERNEL);
769 	if (!mtd->eraseregions)
770 		goto setup_err;
771 
772 	for (i=0; i<cfi->cfiq->NumEraseRegions; i++) {
773 		unsigned long ernum, ersize;
774 		ersize = ((cfi->cfiq->EraseRegionInfo[i] >> 8) & ~0xff) * cfi->interleave;
775 		ernum = (cfi->cfiq->EraseRegionInfo[i] & 0xffff) + 1;
776 
777 		if (mtd->erasesize < ersize) {
778 			mtd->erasesize = ersize;
779 		}
780 		for (j=0; j<cfi->numchips; j++) {
781 			mtd->eraseregions[(j*cfi->cfiq->NumEraseRegions)+i].offset = (j*devsize)+offset;
782 			mtd->eraseregions[(j*cfi->cfiq->NumEraseRegions)+i].erasesize = ersize;
783 			mtd->eraseregions[(j*cfi->cfiq->NumEraseRegions)+i].numblocks = ernum;
784 		}
785 		offset += (ersize * ernum);
786 	}
787 	if (offset != devsize) {
788 		/* Argh */
789 		printk(KERN_WARNING "Sum of regions (%lx) != total size of set of interleaved chips (%lx)\n", offset, devsize);
790 		goto setup_err;
791 	}
792 
793 	__module_get(THIS_MODULE);
794 	register_reboot_notifier(&mtd->reboot_notifier);
795 	return mtd;
796 
797  setup_err:
798 	kfree(mtd->eraseregions);
799 	kfree(mtd);
800 	kfree(cfi->cmdset_priv);
801 	return NULL;
802 }
803 
804 /*
805  * Return true if the chip is ready.
806  *
807  * Ready is one of: read mode, query mode, erase-suspend-read mode (in any
808  * non-suspended sector) and is indicated by no toggle bits toggling.
809  *
810  * Note that anything more complicated than checking if no bits are toggling
811  * (including checking DQ5 for an error status) is tricky to get working
812  * correctly and is therefore not done	(particularly with interleaved chips
813  * as each chip must be checked independently of the others).
814  */
815 static int __xipram chip_ready(struct map_info *map, struct flchip *chip,
816 			       unsigned long addr)
817 {
818 	struct cfi_private *cfi = map->fldrv_priv;
819 	map_word d, t;
820 
821 	if (cfi_use_status_reg(cfi)) {
822 		map_word ready = CMD(CFI_SR_DRB);
823 		/*
824 		 * For chips that support status register, check device
825 		 * ready bit
826 		 */
827 		cfi_send_gen_cmd(0x70, cfi->addr_unlock1, chip->start, map, cfi,
828 				 cfi->device_type, NULL);
829 		d = map_read(map, addr);
830 
831 		return map_word_andequal(map, d, ready, ready);
832 	}
833 
834 	d = map_read(map, addr);
835 	t = map_read(map, addr);
836 
837 	return map_word_equal(map, d, t);
838 }
839 
840 /*
841  * Return true if the chip is ready and has the correct value.
842  *
843  * Ready is one of: read mode, query mode, erase-suspend-read mode (in any
844  * non-suspended sector) and it is indicated by no bits toggling.
845  *
846  * Error are indicated by toggling bits or bits held with the wrong value,
847  * or with bits toggling.
848  *
849  * Note that anything more complicated than checking if no bits are toggling
850  * (including checking DQ5 for an error status) is tricky to get working
851  * correctly and is therefore not done	(particularly with interleaved chips
852  * as each chip must be checked independently of the others).
853  *
854  */
855 static int __xipram chip_good(struct map_info *map, struct flchip *chip,
856 			      unsigned long addr, map_word expected)
857 {
858 	struct cfi_private *cfi = map->fldrv_priv;
859 	map_word oldd, curd;
860 
861 	if (cfi_use_status_reg(cfi)) {
862 		map_word ready = CMD(CFI_SR_DRB);
863 
864 		/*
865 		 * For chips that support status register, check device
866 		 * ready bit
867 		 */
868 		cfi_send_gen_cmd(0x70, cfi->addr_unlock1, chip->start, map, cfi,
869 				 cfi->device_type, NULL);
870 		curd = map_read(map, addr);
871 
872 		return map_word_andequal(map, curd, ready, ready);
873 	}
874 
875 	oldd = map_read(map, addr);
876 	curd = map_read(map, addr);
877 
878 	return	map_word_equal(map, oldd, curd) &&
879 		map_word_equal(map, curd, expected);
880 }
881 
882 static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr, int mode)
883 {
884 	DECLARE_WAITQUEUE(wait, current);
885 	struct cfi_private *cfi = map->fldrv_priv;
886 	unsigned long timeo;
887 	struct cfi_pri_amdstd *cfip = (struct cfi_pri_amdstd *)cfi->cmdset_priv;
888 
889  resettime:
890 	timeo = jiffies + HZ;
891  retry:
892 	switch (chip->state) {
893 
894 	case FL_STATUS:
895 		for (;;) {
896 			if (chip_ready(map, chip, adr))
897 				break;
898 
899 			if (time_after(jiffies, timeo)) {
900 				printk(KERN_ERR "Waiting for chip to be ready timed out.\n");
901 				return -EIO;
902 			}
903 			mutex_unlock(&chip->mutex);
904 			cfi_udelay(1);
905 			mutex_lock(&chip->mutex);
906 			/* Someone else might have been playing with it. */
907 			goto retry;
908 		}
909 		return 0;
910 
911 	case FL_READY:
912 	case FL_CFI_QUERY:
913 	case FL_JEDEC_QUERY:
914 		return 0;
915 
916 	case FL_ERASING:
917 		if (!cfip || !(cfip->EraseSuspend & (0x1|0x2)) ||
918 		    !(mode == FL_READY || mode == FL_POINT ||
919 		    (mode == FL_WRITING && (cfip->EraseSuspend & 0x2))))
920 			goto sleep;
921 
922 		/* Do not allow suspend iff read/write to EB address */
923 		if ((adr & chip->in_progress_block_mask) ==
924 		    chip->in_progress_block_addr)
925 			goto sleep;
926 
927 		/* Erase suspend */
928 		/* It's harmless to issue the Erase-Suspend and Erase-Resume
929 		 * commands when the erase algorithm isn't in progress. */
930 		map_write(map, CMD(0xB0), chip->in_progress_block_addr);
931 		chip->oldstate = FL_ERASING;
932 		chip->state = FL_ERASE_SUSPENDING;
933 		chip->erase_suspended = 1;
934 		for (;;) {
935 			if (chip_ready(map, chip, adr))
936 				break;
937 
938 			if (time_after(jiffies, timeo)) {
939 				/* Should have suspended the erase by now.
940 				 * Send an Erase-Resume command as either
941 				 * there was an error (so leave the erase
942 				 * routine to recover from it) or we trying to
943 				 * use the erase-in-progress sector. */
944 				put_chip(map, chip, adr);
945 				printk(KERN_ERR "MTD %s(): chip not ready after erase suspend\n", __func__);
946 				return -EIO;
947 			}
948 
949 			mutex_unlock(&chip->mutex);
950 			cfi_udelay(1);
951 			mutex_lock(&chip->mutex);
952 			/* Nobody will touch it while it's in state FL_ERASE_SUSPENDING.
953 			   So we can just loop here. */
954 		}
955 		chip->state = FL_READY;
956 		return 0;
957 
958 	case FL_XIP_WHILE_ERASING:
959 		if (mode != FL_READY && mode != FL_POINT &&
960 		    (!cfip || !(cfip->EraseSuspend&2)))
961 			goto sleep;
962 		chip->oldstate = chip->state;
963 		chip->state = FL_READY;
964 		return 0;
965 
966 	case FL_SHUTDOWN:
967 		/* The machine is rebooting */
968 		return -EIO;
969 
970 	case FL_POINT:
971 		/* Only if there's no operation suspended... */
972 		if (mode == FL_READY && chip->oldstate == FL_READY)
973 			return 0;
974 		fallthrough;
975 	default:
976 	sleep:
977 		set_current_state(TASK_UNINTERRUPTIBLE);
978 		add_wait_queue(&chip->wq, &wait);
979 		mutex_unlock(&chip->mutex);
980 		schedule();
981 		remove_wait_queue(&chip->wq, &wait);
982 		mutex_lock(&chip->mutex);
983 		goto resettime;
984 	}
985 }
986 
987 
988 static void put_chip(struct map_info *map, struct flchip *chip, unsigned long adr)
989 {
990 	struct cfi_private *cfi = map->fldrv_priv;
991 
992 	switch(chip->oldstate) {
993 	case FL_ERASING:
994 		cfi_fixup_m29ew_erase_suspend(map,
995 			chip->in_progress_block_addr);
996 		map_write(map, cfi->sector_erase_cmd, chip->in_progress_block_addr);
997 		cfi_fixup_m29ew_delay_after_resume(cfi);
998 		chip->oldstate = FL_READY;
999 		chip->state = FL_ERASING;
1000 		break;
1001 
1002 	case FL_XIP_WHILE_ERASING:
1003 		chip->state = chip->oldstate;
1004 		chip->oldstate = FL_READY;
1005 		break;
1006 
1007 	case FL_READY:
1008 	case FL_STATUS:
1009 		break;
1010 	default:
1011 		printk(KERN_ERR "MTD: put_chip() called with oldstate %d!!\n", chip->oldstate);
1012 	}
1013 	wake_up(&chip->wq);
1014 }
1015 
1016 #ifdef CONFIG_MTD_XIP
1017 
1018 /*
1019  * No interrupt what so ever can be serviced while the flash isn't in array
1020  * mode.  This is ensured by the xip_disable() and xip_enable() functions
1021  * enclosing any code path where the flash is known not to be in array mode.
1022  * And within a XIP disabled code path, only functions marked with __xipram
1023  * may be called and nothing else (it's a good thing to inspect generated
1024  * assembly to make sure inline functions were actually inlined and that gcc
1025  * didn't emit calls to its own support functions). Also configuring MTD CFI
1026  * support to a single buswidth and a single interleave is also recommended.
1027  */
1028 
1029 static void xip_disable(struct map_info *map, struct flchip *chip,
1030 			unsigned long adr)
1031 {
1032 	/* TODO: chips with no XIP use should ignore and return */
1033 	(void) map_read(map, adr); /* ensure mmu mapping is up to date */
1034 	local_irq_disable();
1035 }
1036 
1037 static void __xipram xip_enable(struct map_info *map, struct flchip *chip,
1038 				unsigned long adr)
1039 {
1040 	struct cfi_private *cfi = map->fldrv_priv;
1041 
1042 	if (chip->state != FL_POINT && chip->state != FL_READY) {
1043 		map_write(map, CMD(0xf0), adr);
1044 		chip->state = FL_READY;
1045 	}
1046 	(void) map_read(map, adr);
1047 	xip_iprefetch();
1048 	local_irq_enable();
1049 }
1050 
1051 /*
1052  * When a delay is required for the flash operation to complete, the
1053  * xip_udelay() function is polling for both the given timeout and pending
1054  * (but still masked) hardware interrupts.  Whenever there is an interrupt
1055  * pending then the flash erase operation is suspended, array mode restored
1056  * and interrupts unmasked.  Task scheduling might also happen at that
1057  * point.  The CPU eventually returns from the interrupt or the call to
1058  * schedule() and the suspended flash operation is resumed for the remaining
1059  * of the delay period.
1060  *
1061  * Warning: this function _will_ fool interrupt latency tracing tools.
1062  */
1063 
1064 static void __xipram xip_udelay(struct map_info *map, struct flchip *chip,
1065 				unsigned long adr, int usec)
1066 {
1067 	struct cfi_private *cfi = map->fldrv_priv;
1068 	struct cfi_pri_amdstd *extp = cfi->cmdset_priv;
1069 	map_word status, OK = CMD(0x80);
1070 	unsigned long suspended, start = xip_currtime();
1071 	flstate_t oldstate;
1072 
1073 	do {
1074 		cpu_relax();
1075 		if (xip_irqpending() && extp &&
1076 		    ((chip->state == FL_ERASING && (extp->EraseSuspend & 2))) &&
1077 		    (cfi_interleave_is_1(cfi) || chip->oldstate == FL_READY)) {
1078 			/*
1079 			 * Let's suspend the erase operation when supported.
1080 			 * Note that we currently don't try to suspend
1081 			 * interleaved chips if there is already another
1082 			 * operation suspended (imagine what happens
1083 			 * when one chip was already done with the current
1084 			 * operation while another chip suspended it, then
1085 			 * we resume the whole thing at once).  Yes, it
1086 			 * can happen!
1087 			 */
1088 			map_write(map, CMD(0xb0), adr);
1089 			usec -= xip_elapsed_since(start);
1090 			suspended = xip_currtime();
1091 			do {
1092 				if (xip_elapsed_since(suspended) > 100000) {
1093 					/*
1094 					 * The chip doesn't want to suspend
1095 					 * after waiting for 100 msecs.
1096 					 * This is a critical error but there
1097 					 * is not much we can do here.
1098 					 */
1099 					return;
1100 				}
1101 				status = map_read(map, adr);
1102 			} while (!map_word_andequal(map, status, OK, OK));
1103 
1104 			/* Suspend succeeded */
1105 			oldstate = chip->state;
1106 			if (!map_word_bitsset(map, status, CMD(0x40)))
1107 				break;
1108 			chip->state = FL_XIP_WHILE_ERASING;
1109 			chip->erase_suspended = 1;
1110 			map_write(map, CMD(0xf0), adr);
1111 			(void) map_read(map, adr);
1112 			xip_iprefetch();
1113 			local_irq_enable();
1114 			mutex_unlock(&chip->mutex);
1115 			xip_iprefetch();
1116 			cond_resched();
1117 
1118 			/*
1119 			 * We're back.  However someone else might have
1120 			 * decided to go write to the chip if we are in
1121 			 * a suspended erase state.  If so let's wait
1122 			 * until it's done.
1123 			 */
1124 			mutex_lock(&chip->mutex);
1125 			while (chip->state != FL_XIP_WHILE_ERASING) {
1126 				DECLARE_WAITQUEUE(wait, current);
1127 				set_current_state(TASK_UNINTERRUPTIBLE);
1128 				add_wait_queue(&chip->wq, &wait);
1129 				mutex_unlock(&chip->mutex);
1130 				schedule();
1131 				remove_wait_queue(&chip->wq, &wait);
1132 				mutex_lock(&chip->mutex);
1133 			}
1134 			/* Disallow XIP again */
1135 			local_irq_disable();
1136 
1137 			/* Correct Erase Suspend Hangups for M29EW */
1138 			cfi_fixup_m29ew_erase_suspend(map, adr);
1139 			/* Resume the write or erase operation */
1140 			map_write(map, cfi->sector_erase_cmd, adr);
1141 			chip->state = oldstate;
1142 			start = xip_currtime();
1143 		} else if (usec >= 1000000/HZ) {
1144 			/*
1145 			 * Try to save on CPU power when waiting delay
1146 			 * is at least a system timer tick period.
1147 			 * No need to be extremely accurate here.
1148 			 */
1149 			xip_cpu_idle();
1150 		}
1151 		status = map_read(map, adr);
1152 	} while (!map_word_andequal(map, status, OK, OK)
1153 		 && xip_elapsed_since(start) < usec);
1154 }
1155 
1156 #define UDELAY(map, chip, adr, usec)  xip_udelay(map, chip, adr, usec)
1157 
1158 /*
1159  * The INVALIDATE_CACHED_RANGE() macro is normally used in parallel while
1160  * the flash is actively programming or erasing since we have to poll for
1161  * the operation to complete anyway.  We can't do that in a generic way with
1162  * a XIP setup so do it before the actual flash operation in this case
1163  * and stub it out from INVALIDATE_CACHE_UDELAY.
1164  */
1165 #define XIP_INVAL_CACHED_RANGE(map, from, size)  \
1166 	INVALIDATE_CACHED_RANGE(map, from, size)
1167 
1168 #define INVALIDATE_CACHE_UDELAY(map, chip, adr, len, usec)  \
1169 	UDELAY(map, chip, adr, usec)
1170 
1171 /*
1172  * Extra notes:
1173  *
1174  * Activating this XIP support changes the way the code works a bit.  For
1175  * example the code to suspend the current process when concurrent access
1176  * happens is never executed because xip_udelay() will always return with the
1177  * same chip state as it was entered with.  This is why there is no care for
1178  * the presence of add_wait_queue() or schedule() calls from within a couple
1179  * xip_disable()'d  areas of code, like in do_erase_oneblock for example.
1180  * The queueing and scheduling are always happening within xip_udelay().
1181  *
1182  * Similarly, get_chip() and put_chip() just happen to always be executed
1183  * with chip->state set to FL_READY (or FL_XIP_WHILE_*) where flash state
1184  * is in array mode, therefore never executing many cases therein and not
1185  * causing any problem with XIP.
1186  */
1187 
1188 #else
1189 
1190 #define xip_disable(map, chip, adr)
1191 #define xip_enable(map, chip, adr)
1192 #define XIP_INVAL_CACHED_RANGE(x...)
1193 
1194 #define UDELAY(map, chip, adr, usec)  \
1195 do {  \
1196 	mutex_unlock(&chip->mutex);  \
1197 	cfi_udelay(usec);  \
1198 	mutex_lock(&chip->mutex);  \
1199 } while (0)
1200 
1201 #define INVALIDATE_CACHE_UDELAY(map, chip, adr, len, usec)  \
1202 do {  \
1203 	mutex_unlock(&chip->mutex);  \
1204 	INVALIDATE_CACHED_RANGE(map, adr, len);  \
1205 	cfi_udelay(usec);  \
1206 	mutex_lock(&chip->mutex);  \
1207 } while (0)
1208 
1209 #endif
1210 
1211 static inline int do_read_onechip(struct map_info *map, struct flchip *chip, loff_t adr, size_t len, u_char *buf)
1212 {
1213 	unsigned long cmd_addr;
1214 	struct cfi_private *cfi = map->fldrv_priv;
1215 	int ret;
1216 
1217 	adr += chip->start;
1218 
1219 	/* Ensure cmd read/writes are aligned. */
1220 	cmd_addr = adr & ~(map_bankwidth(map)-1);
1221 
1222 	mutex_lock(&chip->mutex);
1223 	ret = get_chip(map, chip, cmd_addr, FL_READY);
1224 	if (ret) {
1225 		mutex_unlock(&chip->mutex);
1226 		return ret;
1227 	}
1228 
1229 	if (chip->state != FL_POINT && chip->state != FL_READY) {
1230 		map_write(map, CMD(0xf0), cmd_addr);
1231 		chip->state = FL_READY;
1232 	}
1233 
1234 	map_copy_from(map, buf, adr, len);
1235 
1236 	put_chip(map, chip, cmd_addr);
1237 
1238 	mutex_unlock(&chip->mutex);
1239 	return 0;
1240 }
1241 
1242 
1243 static int cfi_amdstd_read (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf)
1244 {
1245 	struct map_info *map = mtd->priv;
1246 	struct cfi_private *cfi = map->fldrv_priv;
1247 	unsigned long ofs;
1248 	int chipnum;
1249 	int ret = 0;
1250 
1251 	/* ofs: offset within the first chip that the first read should start */
1252 	chipnum = (from >> cfi->chipshift);
1253 	ofs = from - (chipnum <<  cfi->chipshift);
1254 
1255 	while (len) {
1256 		unsigned long thislen;
1257 
1258 		if (chipnum >= cfi->numchips)
1259 			break;
1260 
1261 		if ((len + ofs -1) >> cfi->chipshift)
1262 			thislen = (1<<cfi->chipshift) - ofs;
1263 		else
1264 			thislen = len;
1265 
1266 		ret = do_read_onechip(map, &cfi->chips[chipnum], ofs, thislen, buf);
1267 		if (ret)
1268 			break;
1269 
1270 		*retlen += thislen;
1271 		len -= thislen;
1272 		buf += thislen;
1273 
1274 		ofs = 0;
1275 		chipnum++;
1276 	}
1277 	return ret;
1278 }
1279 
1280 typedef int (*otp_op_t)(struct map_info *map, struct flchip *chip,
1281 			loff_t adr, size_t len, u_char *buf, size_t grouplen);
1282 
1283 static inline void otp_enter(struct map_info *map, struct flchip *chip,
1284 			     loff_t adr, size_t len)
1285 {
1286 	struct cfi_private *cfi = map->fldrv_priv;
1287 
1288 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
1289 			 cfi->device_type, NULL);
1290 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
1291 			 cfi->device_type, NULL);
1292 	cfi_send_gen_cmd(0x88, cfi->addr_unlock1, chip->start, map, cfi,
1293 			 cfi->device_type, NULL);
1294 
1295 	INVALIDATE_CACHED_RANGE(map, chip->start + adr, len);
1296 }
1297 
1298 static inline void otp_exit(struct map_info *map, struct flchip *chip,
1299 			    loff_t adr, size_t len)
1300 {
1301 	struct cfi_private *cfi = map->fldrv_priv;
1302 
1303 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
1304 			 cfi->device_type, NULL);
1305 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
1306 			 cfi->device_type, NULL);
1307 	cfi_send_gen_cmd(0x90, cfi->addr_unlock1, chip->start, map, cfi,
1308 			 cfi->device_type, NULL);
1309 	cfi_send_gen_cmd(0x00, cfi->addr_unlock1, chip->start, map, cfi,
1310 			 cfi->device_type, NULL);
1311 
1312 	INVALIDATE_CACHED_RANGE(map, chip->start + adr, len);
1313 }
1314 
1315 static inline int do_read_secsi_onechip(struct map_info *map,
1316 					struct flchip *chip, loff_t adr,
1317 					size_t len, u_char *buf,
1318 					size_t grouplen)
1319 {
1320 	DECLARE_WAITQUEUE(wait, current);
1321 
1322  retry:
1323 	mutex_lock(&chip->mutex);
1324 
1325 	if (chip->state != FL_READY){
1326 		set_current_state(TASK_UNINTERRUPTIBLE);
1327 		add_wait_queue(&chip->wq, &wait);
1328 
1329 		mutex_unlock(&chip->mutex);
1330 
1331 		schedule();
1332 		remove_wait_queue(&chip->wq, &wait);
1333 
1334 		goto retry;
1335 	}
1336 
1337 	adr += chip->start;
1338 
1339 	chip->state = FL_READY;
1340 
1341 	otp_enter(map, chip, adr, len);
1342 	map_copy_from(map, buf, adr, len);
1343 	otp_exit(map, chip, adr, len);
1344 
1345 	wake_up(&chip->wq);
1346 	mutex_unlock(&chip->mutex);
1347 
1348 	return 0;
1349 }
1350 
1351 static int cfi_amdstd_secsi_read (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf)
1352 {
1353 	struct map_info *map = mtd->priv;
1354 	struct cfi_private *cfi = map->fldrv_priv;
1355 	unsigned long ofs;
1356 	int chipnum;
1357 	int ret = 0;
1358 
1359 	/* ofs: offset within the first chip that the first read should start */
1360 	/* 8 secsi bytes per chip */
1361 	chipnum=from>>3;
1362 	ofs=from & 7;
1363 
1364 	while (len) {
1365 		unsigned long thislen;
1366 
1367 		if (chipnum >= cfi->numchips)
1368 			break;
1369 
1370 		if ((len + ofs -1) >> 3)
1371 			thislen = (1<<3) - ofs;
1372 		else
1373 			thislen = len;
1374 
1375 		ret = do_read_secsi_onechip(map, &cfi->chips[chipnum], ofs,
1376 					    thislen, buf, 0);
1377 		if (ret)
1378 			break;
1379 
1380 		*retlen += thislen;
1381 		len -= thislen;
1382 		buf += thislen;
1383 
1384 		ofs = 0;
1385 		chipnum++;
1386 	}
1387 	return ret;
1388 }
1389 
1390 static int __xipram do_write_oneword(struct map_info *map, struct flchip *chip,
1391 				     unsigned long adr, map_word datum,
1392 				     int mode);
1393 
1394 static int do_otp_write(struct map_info *map, struct flchip *chip, loff_t adr,
1395 			size_t len, u_char *buf, size_t grouplen)
1396 {
1397 	int ret;
1398 	while (len) {
1399 		unsigned long bus_ofs = adr & ~(map_bankwidth(map)-1);
1400 		int gap = adr - bus_ofs;
1401 		int n = min_t(int, len, map_bankwidth(map) - gap);
1402 		map_word datum = map_word_ff(map);
1403 
1404 		if (n != map_bankwidth(map)) {
1405 			/* partial write of a word, load old contents */
1406 			otp_enter(map, chip, bus_ofs, map_bankwidth(map));
1407 			datum = map_read(map, bus_ofs);
1408 			otp_exit(map, chip, bus_ofs, map_bankwidth(map));
1409 		}
1410 
1411 		datum = map_word_load_partial(map, datum, buf, gap, n);
1412 		ret = do_write_oneword(map, chip, bus_ofs, datum, FL_OTP_WRITE);
1413 		if (ret)
1414 			return ret;
1415 
1416 		adr += n;
1417 		buf += n;
1418 		len -= n;
1419 	}
1420 
1421 	return 0;
1422 }
1423 
1424 static int do_otp_lock(struct map_info *map, struct flchip *chip, loff_t adr,
1425 		       size_t len, u_char *buf, size_t grouplen)
1426 {
1427 	struct cfi_private *cfi = map->fldrv_priv;
1428 	uint8_t lockreg;
1429 	unsigned long timeo;
1430 	int ret;
1431 
1432 	/* make sure area matches group boundaries */
1433 	if ((adr != 0) || (len != grouplen))
1434 		return -EINVAL;
1435 
1436 	mutex_lock(&chip->mutex);
1437 	ret = get_chip(map, chip, chip->start, FL_LOCKING);
1438 	if (ret) {
1439 		mutex_unlock(&chip->mutex);
1440 		return ret;
1441 	}
1442 	chip->state = FL_LOCKING;
1443 
1444 	/* Enter lock register command */
1445 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
1446 			 cfi->device_type, NULL);
1447 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
1448 			 cfi->device_type, NULL);
1449 	cfi_send_gen_cmd(0x40, cfi->addr_unlock1, chip->start, map, cfi,
1450 			 cfi->device_type, NULL);
1451 
1452 	/* read lock register */
1453 	lockreg = cfi_read_query(map, 0);
1454 
1455 	/* set bit 0 to protect extended memory block */
1456 	lockreg &= ~0x01;
1457 
1458 	/* set bit 0 to protect extended memory block */
1459 	/* write lock register */
1460 	map_write(map, CMD(0xA0), chip->start);
1461 	map_write(map, CMD(lockreg), chip->start);
1462 
1463 	/* wait for chip to become ready */
1464 	timeo = jiffies + msecs_to_jiffies(2);
1465 	for (;;) {
1466 		if (chip_ready(map, chip, adr))
1467 			break;
1468 
1469 		if (time_after(jiffies, timeo)) {
1470 			pr_err("Waiting for chip to be ready timed out.\n");
1471 			ret = -EIO;
1472 			break;
1473 		}
1474 		UDELAY(map, chip, 0, 1);
1475 	}
1476 
1477 	/* exit protection commands */
1478 	map_write(map, CMD(0x90), chip->start);
1479 	map_write(map, CMD(0x00), chip->start);
1480 
1481 	chip->state = FL_READY;
1482 	put_chip(map, chip, chip->start);
1483 	mutex_unlock(&chip->mutex);
1484 
1485 	return ret;
1486 }
1487 
1488 static int cfi_amdstd_otp_walk(struct mtd_info *mtd, loff_t from, size_t len,
1489 			       size_t *retlen, u_char *buf,
1490 			       otp_op_t action, int user_regs)
1491 {
1492 	struct map_info *map = mtd->priv;
1493 	struct cfi_private *cfi = map->fldrv_priv;
1494 	int ofs_factor = cfi->interleave * cfi->device_type;
1495 	unsigned long base;
1496 	int chipnum;
1497 	struct flchip *chip;
1498 	uint8_t otp, lockreg;
1499 	int ret;
1500 
1501 	size_t user_size, factory_size, otpsize;
1502 	loff_t user_offset, factory_offset, otpoffset;
1503 	int user_locked = 0, otplocked;
1504 
1505 	*retlen = 0;
1506 
1507 	for (chipnum = 0; chipnum < cfi->numchips; chipnum++) {
1508 		chip = &cfi->chips[chipnum];
1509 		factory_size = 0;
1510 		user_size = 0;
1511 
1512 		/* Micron M29EW family */
1513 		if (is_m29ew(cfi)) {
1514 			base = chip->start;
1515 
1516 			/* check whether secsi area is factory locked
1517 			   or user lockable */
1518 			mutex_lock(&chip->mutex);
1519 			ret = get_chip(map, chip, base, FL_CFI_QUERY);
1520 			if (ret) {
1521 				mutex_unlock(&chip->mutex);
1522 				return ret;
1523 			}
1524 			cfi_qry_mode_on(base, map, cfi);
1525 			otp = cfi_read_query(map, base + 0x3 * ofs_factor);
1526 			cfi_qry_mode_off(base, map, cfi);
1527 			put_chip(map, chip, base);
1528 			mutex_unlock(&chip->mutex);
1529 
1530 			if (otp & 0x80) {
1531 				/* factory locked */
1532 				factory_offset = 0;
1533 				factory_size = 0x100;
1534 			} else {
1535 				/* customer lockable */
1536 				user_offset = 0;
1537 				user_size = 0x100;
1538 
1539 				mutex_lock(&chip->mutex);
1540 				ret = get_chip(map, chip, base, FL_LOCKING);
1541 				if (ret) {
1542 					mutex_unlock(&chip->mutex);
1543 					return ret;
1544 				}
1545 
1546 				/* Enter lock register command */
1547 				cfi_send_gen_cmd(0xAA, cfi->addr_unlock1,
1548 						 chip->start, map, cfi,
1549 						 cfi->device_type, NULL);
1550 				cfi_send_gen_cmd(0x55, cfi->addr_unlock2,
1551 						 chip->start, map, cfi,
1552 						 cfi->device_type, NULL);
1553 				cfi_send_gen_cmd(0x40, cfi->addr_unlock1,
1554 						 chip->start, map, cfi,
1555 						 cfi->device_type, NULL);
1556 				/* read lock register */
1557 				lockreg = cfi_read_query(map, 0);
1558 				/* exit protection commands */
1559 				map_write(map, CMD(0x90), chip->start);
1560 				map_write(map, CMD(0x00), chip->start);
1561 				put_chip(map, chip, chip->start);
1562 				mutex_unlock(&chip->mutex);
1563 
1564 				user_locked = ((lockreg & 0x01) == 0x00);
1565 			}
1566 		}
1567 
1568 		otpsize = user_regs ? user_size : factory_size;
1569 		if (!otpsize)
1570 			continue;
1571 		otpoffset = user_regs ? user_offset : factory_offset;
1572 		otplocked = user_regs ? user_locked : 1;
1573 
1574 		if (!action) {
1575 			/* return otpinfo */
1576 			struct otp_info *otpinfo;
1577 			len -= sizeof(*otpinfo);
1578 			if (len <= 0)
1579 				return -ENOSPC;
1580 			otpinfo = (struct otp_info *)buf;
1581 			otpinfo->start = from;
1582 			otpinfo->length = otpsize;
1583 			otpinfo->locked = otplocked;
1584 			buf += sizeof(*otpinfo);
1585 			*retlen += sizeof(*otpinfo);
1586 			from += otpsize;
1587 		} else if ((from < otpsize) && (len > 0)) {
1588 			size_t size;
1589 			size = (len < otpsize - from) ? len : otpsize - from;
1590 			ret = action(map, chip, otpoffset + from, size, buf,
1591 				     otpsize);
1592 			if (ret < 0)
1593 				return ret;
1594 
1595 			buf += size;
1596 			len -= size;
1597 			*retlen += size;
1598 			from = 0;
1599 		} else {
1600 			from -= otpsize;
1601 		}
1602 	}
1603 	return 0;
1604 }
1605 
1606 static int cfi_amdstd_get_fact_prot_info(struct mtd_info *mtd, size_t len,
1607 					 size_t *retlen, struct otp_info *buf)
1608 {
1609 	return cfi_amdstd_otp_walk(mtd, 0, len, retlen, (u_char *)buf,
1610 				   NULL, 0);
1611 }
1612 
1613 static int cfi_amdstd_get_user_prot_info(struct mtd_info *mtd, size_t len,
1614 					 size_t *retlen, struct otp_info *buf)
1615 {
1616 	return cfi_amdstd_otp_walk(mtd, 0, len, retlen, (u_char *)buf,
1617 				   NULL, 1);
1618 }
1619 
1620 static int cfi_amdstd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from,
1621 					 size_t len, size_t *retlen,
1622 					 u_char *buf)
1623 {
1624 	return cfi_amdstd_otp_walk(mtd, from, len, retlen,
1625 				   buf, do_read_secsi_onechip, 0);
1626 }
1627 
1628 static int cfi_amdstd_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
1629 					 size_t len, size_t *retlen,
1630 					 u_char *buf)
1631 {
1632 	return cfi_amdstd_otp_walk(mtd, from, len, retlen,
1633 				   buf, do_read_secsi_onechip, 1);
1634 }
1635 
1636 static int cfi_amdstd_write_user_prot_reg(struct mtd_info *mtd, loff_t from,
1637 					  size_t len, size_t *retlen,
1638 					  const u_char *buf)
1639 {
1640 	return cfi_amdstd_otp_walk(mtd, from, len, retlen, (u_char *)buf,
1641 				   do_otp_write, 1);
1642 }
1643 
1644 static int cfi_amdstd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
1645 					 size_t len)
1646 {
1647 	size_t retlen;
1648 	return cfi_amdstd_otp_walk(mtd, from, len, &retlen, NULL,
1649 				   do_otp_lock, 1);
1650 }
1651 
1652 static int __xipram do_write_oneword_once(struct map_info *map,
1653 					  struct flchip *chip,
1654 					  unsigned long adr, map_word datum,
1655 					  int mode, struct cfi_private *cfi)
1656 {
1657 	unsigned long timeo;
1658 	/*
1659 	 * We use a 1ms + 1 jiffies generic timeout for writes (most devices
1660 	 * have a max write time of a few hundreds usec). However, we should
1661 	 * use the maximum timeout value given by the chip at probe time
1662 	 * instead.  Unfortunately, struct flchip does have a field for
1663 	 * maximum timeout, only for typical which can be far too short
1664 	 * depending of the conditions.	 The ' + 1' is to avoid having a
1665 	 * timeout of 0 jiffies if HZ is smaller than 1000.
1666 	 */
1667 	unsigned long uWriteTimeout = (HZ / 1000) + 1;
1668 	int ret = 0;
1669 
1670 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
1671 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
1672 	cfi_send_gen_cmd(0xA0, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
1673 	map_write(map, datum, adr);
1674 	chip->state = mode;
1675 
1676 	INVALIDATE_CACHE_UDELAY(map, chip,
1677 				adr, map_bankwidth(map),
1678 				chip->word_write_time);
1679 
1680 	/* See comment above for timeout value. */
1681 	timeo = jiffies + uWriteTimeout;
1682 	for (;;) {
1683 		if (chip->state != mode) {
1684 			/* Someone's suspended the write. Sleep */
1685 			DECLARE_WAITQUEUE(wait, current);
1686 
1687 			set_current_state(TASK_UNINTERRUPTIBLE);
1688 			add_wait_queue(&chip->wq, &wait);
1689 			mutex_unlock(&chip->mutex);
1690 			schedule();
1691 			remove_wait_queue(&chip->wq, &wait);
1692 			timeo = jiffies + (HZ / 2); /* FIXME */
1693 			mutex_lock(&chip->mutex);
1694 			continue;
1695 		}
1696 
1697 		/*
1698 		 * We check "time_after" and "!chip_good" before checking
1699 		 * "chip_good" to avoid the failure due to scheduling.
1700 		 */
1701 		if (time_after(jiffies, timeo) &&
1702 		    !chip_good(map, chip, adr, datum)) {
1703 			xip_enable(map, chip, adr);
1704 			printk(KERN_WARNING "MTD %s(): software timeout\n", __func__);
1705 			xip_disable(map, chip, adr);
1706 			ret = -EIO;
1707 			break;
1708 		}
1709 
1710 		if (chip_good(map, chip, adr, datum)) {
1711 			if (cfi_check_err_status(map, chip, adr))
1712 				ret = -EIO;
1713 			break;
1714 		}
1715 
1716 		/* Latency issues. Drop the lock, wait a while and retry */
1717 		UDELAY(map, chip, adr, 1);
1718 	}
1719 
1720 	return ret;
1721 }
1722 
1723 static int __xipram do_write_oneword_start(struct map_info *map,
1724 					   struct flchip *chip,
1725 					   unsigned long adr, int mode)
1726 {
1727 	int ret;
1728 
1729 	mutex_lock(&chip->mutex);
1730 
1731 	ret = get_chip(map, chip, adr, mode);
1732 	if (ret) {
1733 		mutex_unlock(&chip->mutex);
1734 		return ret;
1735 	}
1736 
1737 	if (mode == FL_OTP_WRITE)
1738 		otp_enter(map, chip, adr, map_bankwidth(map));
1739 
1740 	return ret;
1741 }
1742 
1743 static void __xipram do_write_oneword_done(struct map_info *map,
1744 					   struct flchip *chip,
1745 					   unsigned long adr, int mode)
1746 {
1747 	if (mode == FL_OTP_WRITE)
1748 		otp_exit(map, chip, adr, map_bankwidth(map));
1749 
1750 	chip->state = FL_READY;
1751 	DISABLE_VPP(map);
1752 	put_chip(map, chip, adr);
1753 
1754 	mutex_unlock(&chip->mutex);
1755 }
1756 
1757 static int __xipram do_write_oneword_retry(struct map_info *map,
1758 					   struct flchip *chip,
1759 					   unsigned long adr, map_word datum,
1760 					   int mode)
1761 {
1762 	struct cfi_private *cfi = map->fldrv_priv;
1763 	int ret = 0;
1764 	map_word oldd;
1765 	int retry_cnt = 0;
1766 
1767 	/*
1768 	 * Check for a NOP for the case when the datum to write is already
1769 	 * present - it saves time and works around buggy chips that corrupt
1770 	 * data at other locations when 0xff is written to a location that
1771 	 * already contains 0xff.
1772 	 */
1773 	oldd = map_read(map, adr);
1774 	if (map_word_equal(map, oldd, datum)) {
1775 		pr_debug("MTD %s(): NOP\n", __func__);
1776 		return ret;
1777 	}
1778 
1779 	XIP_INVAL_CACHED_RANGE(map, adr, map_bankwidth(map));
1780 	ENABLE_VPP(map);
1781 	xip_disable(map, chip, adr);
1782 
1783  retry:
1784 	ret = do_write_oneword_once(map, chip, adr, datum, mode, cfi);
1785 	if (ret) {
1786 		/* reset on all failures. */
1787 		map_write(map, CMD(0xF0), chip->start);
1788 		/* FIXME - should have reset delay before continuing */
1789 
1790 		if (++retry_cnt <= MAX_RETRIES) {
1791 			ret = 0;
1792 			goto retry;
1793 		}
1794 	}
1795 	xip_enable(map, chip, adr);
1796 
1797 	return ret;
1798 }
1799 
1800 static int __xipram do_write_oneword(struct map_info *map, struct flchip *chip,
1801 				     unsigned long adr, map_word datum,
1802 				     int mode)
1803 {
1804 	int ret;
1805 
1806 	adr += chip->start;
1807 
1808 	pr_debug("MTD %s(): WRITE 0x%.8lx(0x%.8lx)\n", __func__, adr,
1809 		 datum.x[0]);
1810 
1811 	ret = do_write_oneword_start(map, chip, adr, mode);
1812 	if (ret)
1813 		return ret;
1814 
1815 	ret = do_write_oneword_retry(map, chip, adr, datum, mode);
1816 
1817 	do_write_oneword_done(map, chip, adr, mode);
1818 
1819 	return ret;
1820 }
1821 
1822 
1823 static int cfi_amdstd_write_words(struct mtd_info *mtd, loff_t to, size_t len,
1824 				  size_t *retlen, const u_char *buf)
1825 {
1826 	struct map_info *map = mtd->priv;
1827 	struct cfi_private *cfi = map->fldrv_priv;
1828 	int ret;
1829 	int chipnum;
1830 	unsigned long ofs, chipstart;
1831 	DECLARE_WAITQUEUE(wait, current);
1832 
1833 	chipnum = to >> cfi->chipshift;
1834 	ofs = to  - (chipnum << cfi->chipshift);
1835 	chipstart = cfi->chips[chipnum].start;
1836 
1837 	/* If it's not bus-aligned, do the first byte write */
1838 	if (ofs & (map_bankwidth(map)-1)) {
1839 		unsigned long bus_ofs = ofs & ~(map_bankwidth(map)-1);
1840 		int i = ofs - bus_ofs;
1841 		int n = 0;
1842 		map_word tmp_buf;
1843 
1844  retry:
1845 		mutex_lock(&cfi->chips[chipnum].mutex);
1846 
1847 		if (cfi->chips[chipnum].state != FL_READY) {
1848 			set_current_state(TASK_UNINTERRUPTIBLE);
1849 			add_wait_queue(&cfi->chips[chipnum].wq, &wait);
1850 
1851 			mutex_unlock(&cfi->chips[chipnum].mutex);
1852 
1853 			schedule();
1854 			remove_wait_queue(&cfi->chips[chipnum].wq, &wait);
1855 			goto retry;
1856 		}
1857 
1858 		/* Load 'tmp_buf' with old contents of flash */
1859 		tmp_buf = map_read(map, bus_ofs+chipstart);
1860 
1861 		mutex_unlock(&cfi->chips[chipnum].mutex);
1862 
1863 		/* Number of bytes to copy from buffer */
1864 		n = min_t(int, len, map_bankwidth(map)-i);
1865 
1866 		tmp_buf = map_word_load_partial(map, tmp_buf, buf, i, n);
1867 
1868 		ret = do_write_oneword(map, &cfi->chips[chipnum],
1869 				       bus_ofs, tmp_buf, FL_WRITING);
1870 		if (ret)
1871 			return ret;
1872 
1873 		ofs += n;
1874 		buf += n;
1875 		(*retlen) += n;
1876 		len -= n;
1877 
1878 		if (ofs >> cfi->chipshift) {
1879 			chipnum ++;
1880 			ofs = 0;
1881 			if (chipnum == cfi->numchips)
1882 				return 0;
1883 		}
1884 	}
1885 
1886 	/* We are now aligned, write as much as possible */
1887 	while(len >= map_bankwidth(map)) {
1888 		map_word datum;
1889 
1890 		datum = map_word_load(map, buf);
1891 
1892 		ret = do_write_oneword(map, &cfi->chips[chipnum],
1893 				       ofs, datum, FL_WRITING);
1894 		if (ret)
1895 			return ret;
1896 
1897 		ofs += map_bankwidth(map);
1898 		buf += map_bankwidth(map);
1899 		(*retlen) += map_bankwidth(map);
1900 		len -= map_bankwidth(map);
1901 
1902 		if (ofs >> cfi->chipshift) {
1903 			chipnum ++;
1904 			ofs = 0;
1905 			if (chipnum == cfi->numchips)
1906 				return 0;
1907 			chipstart = cfi->chips[chipnum].start;
1908 		}
1909 	}
1910 
1911 	/* Write the trailing bytes if any */
1912 	if (len & (map_bankwidth(map)-1)) {
1913 		map_word tmp_buf;
1914 
1915  retry1:
1916 		mutex_lock(&cfi->chips[chipnum].mutex);
1917 
1918 		if (cfi->chips[chipnum].state != FL_READY) {
1919 			set_current_state(TASK_UNINTERRUPTIBLE);
1920 			add_wait_queue(&cfi->chips[chipnum].wq, &wait);
1921 
1922 			mutex_unlock(&cfi->chips[chipnum].mutex);
1923 
1924 			schedule();
1925 			remove_wait_queue(&cfi->chips[chipnum].wq, &wait);
1926 			goto retry1;
1927 		}
1928 
1929 		tmp_buf = map_read(map, ofs + chipstart);
1930 
1931 		mutex_unlock(&cfi->chips[chipnum].mutex);
1932 
1933 		tmp_buf = map_word_load_partial(map, tmp_buf, buf, 0, len);
1934 
1935 		ret = do_write_oneword(map, &cfi->chips[chipnum],
1936 				       ofs, tmp_buf, FL_WRITING);
1937 		if (ret)
1938 			return ret;
1939 
1940 		(*retlen) += len;
1941 	}
1942 
1943 	return 0;
1944 }
1945 
1946 #if !FORCE_WORD_WRITE
1947 static int __xipram do_write_buffer_wait(struct map_info *map,
1948 					 struct flchip *chip, unsigned long adr,
1949 					 map_word datum)
1950 {
1951 	unsigned long timeo;
1952 	unsigned long u_write_timeout;
1953 	int ret = 0;
1954 
1955 	/*
1956 	 * Timeout is calculated according to CFI data, if available.
1957 	 * See more comments in cfi_cmdset_0002().
1958 	 */
1959 	u_write_timeout = usecs_to_jiffies(chip->buffer_write_time_max);
1960 	timeo = jiffies + u_write_timeout;
1961 
1962 	for (;;) {
1963 		if (chip->state != FL_WRITING) {
1964 			/* Someone's suspended the write. Sleep */
1965 			DECLARE_WAITQUEUE(wait, current);
1966 
1967 			set_current_state(TASK_UNINTERRUPTIBLE);
1968 			add_wait_queue(&chip->wq, &wait);
1969 			mutex_unlock(&chip->mutex);
1970 			schedule();
1971 			remove_wait_queue(&chip->wq, &wait);
1972 			timeo = jiffies + (HZ / 2); /* FIXME */
1973 			mutex_lock(&chip->mutex);
1974 			continue;
1975 		}
1976 
1977 		/*
1978 		 * We check "time_after" and "!chip_good" before checking
1979 		 * "chip_good" to avoid the failure due to scheduling.
1980 		 */
1981 		if (time_after(jiffies, timeo) &&
1982 		    !chip_good(map, chip, adr, datum)) {
1983 			pr_err("MTD %s(): software timeout, address:0x%.8lx.\n",
1984 			       __func__, adr);
1985 			ret = -EIO;
1986 			break;
1987 		}
1988 
1989 		if (chip_good(map, chip, adr, datum)) {
1990 			if (cfi_check_err_status(map, chip, adr))
1991 				ret = -EIO;
1992 			break;
1993 		}
1994 
1995 		/* Latency issues. Drop the lock, wait a while and retry */
1996 		UDELAY(map, chip, adr, 1);
1997 	}
1998 
1999 	return ret;
2000 }
2001 
2002 static void __xipram do_write_buffer_reset(struct map_info *map,
2003 					   struct flchip *chip,
2004 					   struct cfi_private *cfi)
2005 {
2006 	/*
2007 	 * Recovery from write-buffer programming failures requires
2008 	 * the write-to-buffer-reset sequence.  Since the last part
2009 	 * of the sequence also works as a normal reset, we can run
2010 	 * the same commands regardless of why we are here.
2011 	 * See e.g.
2012 	 * http://www.spansion.com/Support/Application%20Notes/MirrorBit_Write_Buffer_Prog_Page_Buffer_Read_AN.pdf
2013 	 */
2014 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
2015 			 cfi->device_type, NULL);
2016 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
2017 			 cfi->device_type, NULL);
2018 	cfi_send_gen_cmd(0xF0, cfi->addr_unlock1, chip->start, map, cfi,
2019 			 cfi->device_type, NULL);
2020 
2021 	/* FIXME - should have reset delay before continuing */
2022 }
2023 
2024 /*
2025  * FIXME: interleaved mode not tested, and probably not supported!
2026  */
2027 static int __xipram do_write_buffer(struct map_info *map, struct flchip *chip,
2028 				    unsigned long adr, const u_char *buf,
2029 				    int len)
2030 {
2031 	struct cfi_private *cfi = map->fldrv_priv;
2032 	int ret;
2033 	unsigned long cmd_adr;
2034 	int z, words;
2035 	map_word datum;
2036 
2037 	adr += chip->start;
2038 	cmd_adr = adr;
2039 
2040 	mutex_lock(&chip->mutex);
2041 	ret = get_chip(map, chip, adr, FL_WRITING);
2042 	if (ret) {
2043 		mutex_unlock(&chip->mutex);
2044 		return ret;
2045 	}
2046 
2047 	datum = map_word_load(map, buf);
2048 
2049 	pr_debug("MTD %s(): WRITE 0x%.8lx(0x%.8lx)\n",
2050 		 __func__, adr, datum.x[0]);
2051 
2052 	XIP_INVAL_CACHED_RANGE(map, adr, len);
2053 	ENABLE_VPP(map);
2054 	xip_disable(map, chip, cmd_adr);
2055 
2056 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
2057 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
2058 
2059 	/* Write Buffer Load */
2060 	map_write(map, CMD(0x25), cmd_adr);
2061 
2062 	chip->state = FL_WRITING_TO_BUFFER;
2063 
2064 	/* Write length of data to come */
2065 	words = len / map_bankwidth(map);
2066 	map_write(map, CMD(words - 1), cmd_adr);
2067 	/* Write data */
2068 	z = 0;
2069 	while(z < words * map_bankwidth(map)) {
2070 		datum = map_word_load(map, buf);
2071 		map_write(map, datum, adr + z);
2072 
2073 		z += map_bankwidth(map);
2074 		buf += map_bankwidth(map);
2075 	}
2076 	z -= map_bankwidth(map);
2077 
2078 	adr += z;
2079 
2080 	/* Write Buffer Program Confirm: GO GO GO */
2081 	map_write(map, CMD(0x29), cmd_adr);
2082 	chip->state = FL_WRITING;
2083 
2084 	INVALIDATE_CACHE_UDELAY(map, chip,
2085 				adr, map_bankwidth(map),
2086 				chip->word_write_time);
2087 
2088 	ret = do_write_buffer_wait(map, chip, adr, datum);
2089 	if (ret)
2090 		do_write_buffer_reset(map, chip, cfi);
2091 
2092 	xip_enable(map, chip, adr);
2093 
2094 	chip->state = FL_READY;
2095 	DISABLE_VPP(map);
2096 	put_chip(map, chip, adr);
2097 	mutex_unlock(&chip->mutex);
2098 
2099 	return ret;
2100 }
2101 
2102 
2103 static int cfi_amdstd_write_buffers(struct mtd_info *mtd, loff_t to, size_t len,
2104 				    size_t *retlen, const u_char *buf)
2105 {
2106 	struct map_info *map = mtd->priv;
2107 	struct cfi_private *cfi = map->fldrv_priv;
2108 	int wbufsize = cfi_interleave(cfi) << cfi->cfiq->MaxBufWriteSize;
2109 	int ret;
2110 	int chipnum;
2111 	unsigned long ofs;
2112 
2113 	chipnum = to >> cfi->chipshift;
2114 	ofs = to  - (chipnum << cfi->chipshift);
2115 
2116 	/* If it's not bus-aligned, do the first word write */
2117 	if (ofs & (map_bankwidth(map)-1)) {
2118 		size_t local_len = (-ofs)&(map_bankwidth(map)-1);
2119 		if (local_len > len)
2120 			local_len = len;
2121 		ret = cfi_amdstd_write_words(mtd, ofs + (chipnum<<cfi->chipshift),
2122 					     local_len, retlen, buf);
2123 		if (ret)
2124 			return ret;
2125 		ofs += local_len;
2126 		buf += local_len;
2127 		len -= local_len;
2128 
2129 		if (ofs >> cfi->chipshift) {
2130 			chipnum ++;
2131 			ofs = 0;
2132 			if (chipnum == cfi->numchips)
2133 				return 0;
2134 		}
2135 	}
2136 
2137 	/* Write buffer is worth it only if more than one word to write... */
2138 	while (len >= map_bankwidth(map) * 2) {
2139 		/* We must not cross write block boundaries */
2140 		int size = wbufsize - (ofs & (wbufsize-1));
2141 
2142 		if (size > len)
2143 			size = len;
2144 		if (size % map_bankwidth(map))
2145 			size -= size % map_bankwidth(map);
2146 
2147 		ret = do_write_buffer(map, &cfi->chips[chipnum],
2148 				      ofs, buf, size);
2149 		if (ret)
2150 			return ret;
2151 
2152 		ofs += size;
2153 		buf += size;
2154 		(*retlen) += size;
2155 		len -= size;
2156 
2157 		if (ofs >> cfi->chipshift) {
2158 			chipnum ++;
2159 			ofs = 0;
2160 			if (chipnum == cfi->numchips)
2161 				return 0;
2162 		}
2163 	}
2164 
2165 	if (len) {
2166 		size_t retlen_dregs = 0;
2167 
2168 		ret = cfi_amdstd_write_words(mtd, ofs + (chipnum<<cfi->chipshift),
2169 					     len, &retlen_dregs, buf);
2170 
2171 		*retlen += retlen_dregs;
2172 		return ret;
2173 	}
2174 
2175 	return 0;
2176 }
2177 #endif /* !FORCE_WORD_WRITE */
2178 
2179 /*
2180  * Wait for the flash chip to become ready to write data
2181  *
2182  * This is only called during the panic_write() path. When panic_write()
2183  * is called, the kernel is in the process of a panic, and will soon be
2184  * dead. Therefore we don't take any locks, and attempt to get access
2185  * to the chip as soon as possible.
2186  */
2187 static int cfi_amdstd_panic_wait(struct map_info *map, struct flchip *chip,
2188 				 unsigned long adr)
2189 {
2190 	struct cfi_private *cfi = map->fldrv_priv;
2191 	int retries = 10;
2192 	int i;
2193 
2194 	/*
2195 	 * If the driver thinks the chip is idle, and no toggle bits
2196 	 * are changing, then the chip is actually idle for sure.
2197 	 */
2198 	if (chip->state == FL_READY && chip_ready(map, chip, adr))
2199 		return 0;
2200 
2201 	/*
2202 	 * Try several times to reset the chip and then wait for it
2203 	 * to become idle. The upper limit of a few milliseconds of
2204 	 * delay isn't a big problem: the kernel is dying anyway. It
2205 	 * is more important to save the messages.
2206 	 */
2207 	while (retries > 0) {
2208 		const unsigned long timeo = (HZ / 1000) + 1;
2209 
2210 		/* send the reset command */
2211 		map_write(map, CMD(0xF0), chip->start);
2212 
2213 		/* wait for the chip to become ready */
2214 		for (i = 0; i < jiffies_to_usecs(timeo); i++) {
2215 			if (chip_ready(map, chip, adr))
2216 				return 0;
2217 
2218 			udelay(1);
2219 		}
2220 
2221 		retries--;
2222 	}
2223 
2224 	/* the chip never became ready */
2225 	return -EBUSY;
2226 }
2227 
2228 /*
2229  * Write out one word of data to a single flash chip during a kernel panic
2230  *
2231  * This is only called during the panic_write() path. When panic_write()
2232  * is called, the kernel is in the process of a panic, and will soon be
2233  * dead. Therefore we don't take any locks, and attempt to get access
2234  * to the chip as soon as possible.
2235  *
2236  * The implementation of this routine is intentionally similar to
2237  * do_write_oneword(), in order to ease code maintenance.
2238  */
2239 static int do_panic_write_oneword(struct map_info *map, struct flchip *chip,
2240 				  unsigned long adr, map_word datum)
2241 {
2242 	const unsigned long uWriteTimeout = (HZ / 1000) + 1;
2243 	struct cfi_private *cfi = map->fldrv_priv;
2244 	int retry_cnt = 0;
2245 	map_word oldd;
2246 	int ret;
2247 	int i;
2248 
2249 	adr += chip->start;
2250 
2251 	ret = cfi_amdstd_panic_wait(map, chip, adr);
2252 	if (ret)
2253 		return ret;
2254 
2255 	pr_debug("MTD %s(): PANIC WRITE 0x%.8lx(0x%.8lx)\n",
2256 			__func__, adr, datum.x[0]);
2257 
2258 	/*
2259 	 * Check for a NOP for the case when the datum to write is already
2260 	 * present - it saves time and works around buggy chips that corrupt
2261 	 * data at other locations when 0xff is written to a location that
2262 	 * already contains 0xff.
2263 	 */
2264 	oldd = map_read(map, adr);
2265 	if (map_word_equal(map, oldd, datum)) {
2266 		pr_debug("MTD %s(): NOP\n", __func__);
2267 		goto op_done;
2268 	}
2269 
2270 	ENABLE_VPP(map);
2271 
2272 retry:
2273 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
2274 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
2275 	cfi_send_gen_cmd(0xA0, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
2276 	map_write(map, datum, adr);
2277 
2278 	for (i = 0; i < jiffies_to_usecs(uWriteTimeout); i++) {
2279 		if (chip_ready(map, chip, adr))
2280 			break;
2281 
2282 		udelay(1);
2283 	}
2284 
2285 	if (!chip_good(map, chip, adr, datum) ||
2286 	    cfi_check_err_status(map, chip, adr)) {
2287 		/* reset on all failures. */
2288 		map_write(map, CMD(0xF0), chip->start);
2289 		/* FIXME - should have reset delay before continuing */
2290 
2291 		if (++retry_cnt <= MAX_RETRIES)
2292 			goto retry;
2293 
2294 		ret = -EIO;
2295 	}
2296 
2297 op_done:
2298 	DISABLE_VPP(map);
2299 	return ret;
2300 }
2301 
2302 /*
2303  * Write out some data during a kernel panic
2304  *
2305  * This is used by the mtdoops driver to save the dying messages from a
2306  * kernel which has panic'd.
2307  *
2308  * This routine ignores all of the locking used throughout the rest of the
2309  * driver, in order to ensure that the data gets written out no matter what
2310  * state this driver (and the flash chip itself) was in when the kernel crashed.
2311  *
2312  * The implementation of this routine is intentionally similar to
2313  * cfi_amdstd_write_words(), in order to ease code maintenance.
2314  */
2315 static int cfi_amdstd_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
2316 				  size_t *retlen, const u_char *buf)
2317 {
2318 	struct map_info *map = mtd->priv;
2319 	struct cfi_private *cfi = map->fldrv_priv;
2320 	unsigned long ofs, chipstart;
2321 	int ret;
2322 	int chipnum;
2323 
2324 	chipnum = to >> cfi->chipshift;
2325 	ofs = to - (chipnum << cfi->chipshift);
2326 	chipstart = cfi->chips[chipnum].start;
2327 
2328 	/* If it's not bus aligned, do the first byte write */
2329 	if (ofs & (map_bankwidth(map) - 1)) {
2330 		unsigned long bus_ofs = ofs & ~(map_bankwidth(map) - 1);
2331 		int i = ofs - bus_ofs;
2332 		int n = 0;
2333 		map_word tmp_buf;
2334 
2335 		ret = cfi_amdstd_panic_wait(map, &cfi->chips[chipnum], bus_ofs);
2336 		if (ret)
2337 			return ret;
2338 
2339 		/* Load 'tmp_buf' with old contents of flash */
2340 		tmp_buf = map_read(map, bus_ofs + chipstart);
2341 
2342 		/* Number of bytes to copy from buffer */
2343 		n = min_t(int, len, map_bankwidth(map) - i);
2344 
2345 		tmp_buf = map_word_load_partial(map, tmp_buf, buf, i, n);
2346 
2347 		ret = do_panic_write_oneword(map, &cfi->chips[chipnum],
2348 					     bus_ofs, tmp_buf);
2349 		if (ret)
2350 			return ret;
2351 
2352 		ofs += n;
2353 		buf += n;
2354 		(*retlen) += n;
2355 		len -= n;
2356 
2357 		if (ofs >> cfi->chipshift) {
2358 			chipnum++;
2359 			ofs = 0;
2360 			if (chipnum == cfi->numchips)
2361 				return 0;
2362 		}
2363 	}
2364 
2365 	/* We are now aligned, write as much as possible */
2366 	while (len >= map_bankwidth(map)) {
2367 		map_word datum;
2368 
2369 		datum = map_word_load(map, buf);
2370 
2371 		ret = do_panic_write_oneword(map, &cfi->chips[chipnum],
2372 					     ofs, datum);
2373 		if (ret)
2374 			return ret;
2375 
2376 		ofs += map_bankwidth(map);
2377 		buf += map_bankwidth(map);
2378 		(*retlen) += map_bankwidth(map);
2379 		len -= map_bankwidth(map);
2380 
2381 		if (ofs >> cfi->chipshift) {
2382 			chipnum++;
2383 			ofs = 0;
2384 			if (chipnum == cfi->numchips)
2385 				return 0;
2386 
2387 			chipstart = cfi->chips[chipnum].start;
2388 		}
2389 	}
2390 
2391 	/* Write the trailing bytes if any */
2392 	if (len & (map_bankwidth(map) - 1)) {
2393 		map_word tmp_buf;
2394 
2395 		ret = cfi_amdstd_panic_wait(map, &cfi->chips[chipnum], ofs);
2396 		if (ret)
2397 			return ret;
2398 
2399 		tmp_buf = map_read(map, ofs + chipstart);
2400 
2401 		tmp_buf = map_word_load_partial(map, tmp_buf, buf, 0, len);
2402 
2403 		ret = do_panic_write_oneword(map, &cfi->chips[chipnum],
2404 					     ofs, tmp_buf);
2405 		if (ret)
2406 			return ret;
2407 
2408 		(*retlen) += len;
2409 	}
2410 
2411 	return 0;
2412 }
2413 
2414 
2415 /*
2416  * Handle devices with one erase region, that only implement
2417  * the chip erase command.
2418  */
2419 static int __xipram do_erase_chip(struct map_info *map, struct flchip *chip)
2420 {
2421 	struct cfi_private *cfi = map->fldrv_priv;
2422 	unsigned long timeo = jiffies + HZ;
2423 	unsigned long int adr;
2424 	DECLARE_WAITQUEUE(wait, current);
2425 	int ret;
2426 	int retry_cnt = 0;
2427 
2428 	adr = cfi->addr_unlock1;
2429 
2430 	mutex_lock(&chip->mutex);
2431 	ret = get_chip(map, chip, adr, FL_ERASING);
2432 	if (ret) {
2433 		mutex_unlock(&chip->mutex);
2434 		return ret;
2435 	}
2436 
2437 	pr_debug("MTD %s(): ERASE 0x%.8lx\n",
2438 	       __func__, chip->start);
2439 
2440 	XIP_INVAL_CACHED_RANGE(map, adr, map->size);
2441 	ENABLE_VPP(map);
2442 	xip_disable(map, chip, adr);
2443 
2444  retry:
2445 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
2446 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
2447 	cfi_send_gen_cmd(0x80, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
2448 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
2449 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
2450 	cfi_send_gen_cmd(0x10, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
2451 
2452 	chip->state = FL_ERASING;
2453 	chip->erase_suspended = 0;
2454 	chip->in_progress_block_addr = adr;
2455 	chip->in_progress_block_mask = ~(map->size - 1);
2456 
2457 	INVALIDATE_CACHE_UDELAY(map, chip,
2458 				adr, map->size,
2459 				chip->erase_time*500);
2460 
2461 	timeo = jiffies + (HZ*20);
2462 
2463 	for (;;) {
2464 		if (chip->state != FL_ERASING) {
2465 			/* Someone's suspended the erase. Sleep */
2466 			set_current_state(TASK_UNINTERRUPTIBLE);
2467 			add_wait_queue(&chip->wq, &wait);
2468 			mutex_unlock(&chip->mutex);
2469 			schedule();
2470 			remove_wait_queue(&chip->wq, &wait);
2471 			mutex_lock(&chip->mutex);
2472 			continue;
2473 		}
2474 		if (chip->erase_suspended) {
2475 			/* This erase was suspended and resumed.
2476 			   Adjust the timeout */
2477 			timeo = jiffies + (HZ*20); /* FIXME */
2478 			chip->erase_suspended = 0;
2479 		}
2480 
2481 		if (chip_good(map, chip, adr, map_word_ff(map))) {
2482 			if (cfi_check_err_status(map, chip, adr))
2483 				ret = -EIO;
2484 			break;
2485 		}
2486 
2487 		if (time_after(jiffies, timeo)) {
2488 			printk(KERN_WARNING "MTD %s(): software timeout\n",
2489 			       __func__);
2490 			ret = -EIO;
2491 			break;
2492 		}
2493 
2494 		/* Latency issues. Drop the lock, wait a while and retry */
2495 		UDELAY(map, chip, adr, 1000000/HZ);
2496 	}
2497 	/* Did we succeed? */
2498 	if (ret) {
2499 		/* reset on all failures. */
2500 		map_write(map, CMD(0xF0), chip->start);
2501 		/* FIXME - should have reset delay before continuing */
2502 
2503 		if (++retry_cnt <= MAX_RETRIES) {
2504 			ret = 0;
2505 			goto retry;
2506 		}
2507 	}
2508 
2509 	chip->state = FL_READY;
2510 	xip_enable(map, chip, adr);
2511 	DISABLE_VPP(map);
2512 	put_chip(map, chip, adr);
2513 	mutex_unlock(&chip->mutex);
2514 
2515 	return ret;
2516 }
2517 
2518 
2519 static int __xipram do_erase_oneblock(struct map_info *map, struct flchip *chip, unsigned long adr, int len, void *thunk)
2520 {
2521 	struct cfi_private *cfi = map->fldrv_priv;
2522 	unsigned long timeo = jiffies + HZ;
2523 	DECLARE_WAITQUEUE(wait, current);
2524 	int ret;
2525 	int retry_cnt = 0;
2526 
2527 	adr += chip->start;
2528 
2529 	mutex_lock(&chip->mutex);
2530 	ret = get_chip(map, chip, adr, FL_ERASING);
2531 	if (ret) {
2532 		mutex_unlock(&chip->mutex);
2533 		return ret;
2534 	}
2535 
2536 	pr_debug("MTD %s(): ERASE 0x%.8lx\n",
2537 		 __func__, adr);
2538 
2539 	XIP_INVAL_CACHED_RANGE(map, adr, len);
2540 	ENABLE_VPP(map);
2541 	xip_disable(map, chip, adr);
2542 
2543  retry:
2544 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
2545 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
2546 	cfi_send_gen_cmd(0x80, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
2547 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
2548 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
2549 	map_write(map, cfi->sector_erase_cmd, adr);
2550 
2551 	chip->state = FL_ERASING;
2552 	chip->erase_suspended = 0;
2553 	chip->in_progress_block_addr = adr;
2554 	chip->in_progress_block_mask = ~(len - 1);
2555 
2556 	INVALIDATE_CACHE_UDELAY(map, chip,
2557 				adr, len,
2558 				chip->erase_time*500);
2559 
2560 	timeo = jiffies + (HZ*20);
2561 
2562 	for (;;) {
2563 		if (chip->state != FL_ERASING) {
2564 			/* Someone's suspended the erase. Sleep */
2565 			set_current_state(TASK_UNINTERRUPTIBLE);
2566 			add_wait_queue(&chip->wq, &wait);
2567 			mutex_unlock(&chip->mutex);
2568 			schedule();
2569 			remove_wait_queue(&chip->wq, &wait);
2570 			mutex_lock(&chip->mutex);
2571 			continue;
2572 		}
2573 		if (chip->erase_suspended) {
2574 			/* This erase was suspended and resumed.
2575 			   Adjust the timeout */
2576 			timeo = jiffies + (HZ*20); /* FIXME */
2577 			chip->erase_suspended = 0;
2578 		}
2579 
2580 		if (chip_good(map, chip, adr, map_word_ff(map))) {
2581 			if (cfi_check_err_status(map, chip, adr))
2582 				ret = -EIO;
2583 			break;
2584 		}
2585 
2586 		if (time_after(jiffies, timeo)) {
2587 			printk(KERN_WARNING "MTD %s(): software timeout\n",
2588 			       __func__);
2589 			ret = -EIO;
2590 			break;
2591 		}
2592 
2593 		/* Latency issues. Drop the lock, wait a while and retry */
2594 		UDELAY(map, chip, adr, 1000000/HZ);
2595 	}
2596 	/* Did we succeed? */
2597 	if (ret) {
2598 		/* reset on all failures. */
2599 		map_write(map, CMD(0xF0), chip->start);
2600 		/* FIXME - should have reset delay before continuing */
2601 
2602 		if (++retry_cnt <= MAX_RETRIES) {
2603 			ret = 0;
2604 			goto retry;
2605 		}
2606 	}
2607 
2608 	chip->state = FL_READY;
2609 	xip_enable(map, chip, adr);
2610 	DISABLE_VPP(map);
2611 	put_chip(map, chip, adr);
2612 	mutex_unlock(&chip->mutex);
2613 	return ret;
2614 }
2615 
2616 
2617 static int cfi_amdstd_erase_varsize(struct mtd_info *mtd, struct erase_info *instr)
2618 {
2619 	return cfi_varsize_frob(mtd, do_erase_oneblock, instr->addr,
2620 				instr->len, NULL);
2621 }
2622 
2623 
2624 static int cfi_amdstd_erase_chip(struct mtd_info *mtd, struct erase_info *instr)
2625 {
2626 	struct map_info *map = mtd->priv;
2627 	struct cfi_private *cfi = map->fldrv_priv;
2628 
2629 	if (instr->addr != 0)
2630 		return -EINVAL;
2631 
2632 	if (instr->len != mtd->size)
2633 		return -EINVAL;
2634 
2635 	return do_erase_chip(map, &cfi->chips[0]);
2636 }
2637 
2638 static int do_atmel_lock(struct map_info *map, struct flchip *chip,
2639 			 unsigned long adr, int len, void *thunk)
2640 {
2641 	struct cfi_private *cfi = map->fldrv_priv;
2642 	int ret;
2643 
2644 	mutex_lock(&chip->mutex);
2645 	ret = get_chip(map, chip, adr + chip->start, FL_LOCKING);
2646 	if (ret)
2647 		goto out_unlock;
2648 	chip->state = FL_LOCKING;
2649 
2650 	pr_debug("MTD %s(): LOCK 0x%08lx len %d\n", __func__, adr, len);
2651 
2652 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
2653 			 cfi->device_type, NULL);
2654 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
2655 			 cfi->device_type, NULL);
2656 	cfi_send_gen_cmd(0x80, cfi->addr_unlock1, chip->start, map, cfi,
2657 			 cfi->device_type, NULL);
2658 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
2659 			 cfi->device_type, NULL);
2660 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
2661 			 cfi->device_type, NULL);
2662 	map_write(map, CMD(0x40), chip->start + adr);
2663 
2664 	chip->state = FL_READY;
2665 	put_chip(map, chip, adr + chip->start);
2666 	ret = 0;
2667 
2668 out_unlock:
2669 	mutex_unlock(&chip->mutex);
2670 	return ret;
2671 }
2672 
2673 static int do_atmel_unlock(struct map_info *map, struct flchip *chip,
2674 			   unsigned long adr, int len, void *thunk)
2675 {
2676 	struct cfi_private *cfi = map->fldrv_priv;
2677 	int ret;
2678 
2679 	mutex_lock(&chip->mutex);
2680 	ret = get_chip(map, chip, adr + chip->start, FL_UNLOCKING);
2681 	if (ret)
2682 		goto out_unlock;
2683 	chip->state = FL_UNLOCKING;
2684 
2685 	pr_debug("MTD %s(): LOCK 0x%08lx len %d\n", __func__, adr, len);
2686 
2687 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
2688 			 cfi->device_type, NULL);
2689 	map_write(map, CMD(0x70), adr);
2690 
2691 	chip->state = FL_READY;
2692 	put_chip(map, chip, adr + chip->start);
2693 	ret = 0;
2694 
2695 out_unlock:
2696 	mutex_unlock(&chip->mutex);
2697 	return ret;
2698 }
2699 
2700 static int cfi_atmel_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
2701 {
2702 	return cfi_varsize_frob(mtd, do_atmel_lock, ofs, len, NULL);
2703 }
2704 
2705 static int cfi_atmel_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
2706 {
2707 	return cfi_varsize_frob(mtd, do_atmel_unlock, ofs, len, NULL);
2708 }
2709 
2710 /*
2711  * Advanced Sector Protection - PPB (Persistent Protection Bit) locking
2712  */
2713 
2714 struct ppb_lock {
2715 	struct flchip *chip;
2716 	unsigned long adr;
2717 	int locked;
2718 };
2719 
2720 #define DO_XXLOCK_ONEBLOCK_LOCK		((void *)1)
2721 #define DO_XXLOCK_ONEBLOCK_UNLOCK	((void *)2)
2722 #define DO_XXLOCK_ONEBLOCK_GETLOCK	((void *)3)
2723 
2724 static int __maybe_unused do_ppb_xxlock(struct map_info *map,
2725 					struct flchip *chip,
2726 					unsigned long adr, int len, void *thunk)
2727 {
2728 	struct cfi_private *cfi = map->fldrv_priv;
2729 	unsigned long timeo;
2730 	int ret;
2731 
2732 	adr += chip->start;
2733 	mutex_lock(&chip->mutex);
2734 	ret = get_chip(map, chip, adr, FL_LOCKING);
2735 	if (ret) {
2736 		mutex_unlock(&chip->mutex);
2737 		return ret;
2738 	}
2739 
2740 	pr_debug("MTD %s(): XXLOCK 0x%08lx len %d\n", __func__, adr, len);
2741 
2742 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
2743 			 cfi->device_type, NULL);
2744 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
2745 			 cfi->device_type, NULL);
2746 	/* PPB entry command */
2747 	cfi_send_gen_cmd(0xC0, cfi->addr_unlock1, chip->start, map, cfi,
2748 			 cfi->device_type, NULL);
2749 
2750 	if (thunk == DO_XXLOCK_ONEBLOCK_LOCK) {
2751 		chip->state = FL_LOCKING;
2752 		map_write(map, CMD(0xA0), adr);
2753 		map_write(map, CMD(0x00), adr);
2754 	} else if (thunk == DO_XXLOCK_ONEBLOCK_UNLOCK) {
2755 		/*
2756 		 * Unlocking of one specific sector is not supported, so we
2757 		 * have to unlock all sectors of this device instead
2758 		 */
2759 		chip->state = FL_UNLOCKING;
2760 		map_write(map, CMD(0x80), chip->start);
2761 		map_write(map, CMD(0x30), chip->start);
2762 	} else if (thunk == DO_XXLOCK_ONEBLOCK_GETLOCK) {
2763 		chip->state = FL_JEDEC_QUERY;
2764 		/* Return locked status: 0->locked, 1->unlocked */
2765 		ret = !cfi_read_query(map, adr);
2766 	} else
2767 		BUG();
2768 
2769 	/*
2770 	 * Wait for some time as unlocking of all sectors takes quite long
2771 	 */
2772 	timeo = jiffies + msecs_to_jiffies(2000);	/* 2s max (un)locking */
2773 	for (;;) {
2774 		if (chip_ready(map, chip, adr))
2775 			break;
2776 
2777 		if (time_after(jiffies, timeo)) {
2778 			printk(KERN_ERR "Waiting for chip to be ready timed out.\n");
2779 			ret = -EIO;
2780 			break;
2781 		}
2782 
2783 		UDELAY(map, chip, adr, 1);
2784 	}
2785 
2786 	/* Exit BC commands */
2787 	map_write(map, CMD(0x90), chip->start);
2788 	map_write(map, CMD(0x00), chip->start);
2789 
2790 	chip->state = FL_READY;
2791 	put_chip(map, chip, adr);
2792 	mutex_unlock(&chip->mutex);
2793 
2794 	return ret;
2795 }
2796 
2797 static int __maybe_unused cfi_ppb_lock(struct mtd_info *mtd, loff_t ofs,
2798 				       uint64_t len)
2799 {
2800 	return cfi_varsize_frob(mtd, do_ppb_xxlock, ofs, len,
2801 				DO_XXLOCK_ONEBLOCK_LOCK);
2802 }
2803 
2804 static int __maybe_unused cfi_ppb_unlock(struct mtd_info *mtd, loff_t ofs,
2805 					 uint64_t len)
2806 {
2807 	struct mtd_erase_region_info *regions = mtd->eraseregions;
2808 	struct map_info *map = mtd->priv;
2809 	struct cfi_private *cfi = map->fldrv_priv;
2810 	struct ppb_lock *sect;
2811 	unsigned long adr;
2812 	loff_t offset;
2813 	uint64_t length;
2814 	int chipnum;
2815 	int i;
2816 	int sectors;
2817 	int ret;
2818 	int max_sectors;
2819 
2820 	/*
2821 	 * PPB unlocking always unlocks all sectors of the flash chip.
2822 	 * We need to re-lock all previously locked sectors. So lets
2823 	 * first check the locking status of all sectors and save
2824 	 * it for future use.
2825 	 */
2826 	max_sectors = 0;
2827 	for (i = 0; i < mtd->numeraseregions; i++)
2828 		max_sectors += regions[i].numblocks;
2829 
2830 	sect = kcalloc(max_sectors, sizeof(struct ppb_lock), GFP_KERNEL);
2831 	if (!sect)
2832 		return -ENOMEM;
2833 
2834 	/*
2835 	 * This code to walk all sectors is a slightly modified version
2836 	 * of the cfi_varsize_frob() code.
2837 	 */
2838 	i = 0;
2839 	chipnum = 0;
2840 	adr = 0;
2841 	sectors = 0;
2842 	offset = 0;
2843 	length = mtd->size;
2844 
2845 	while (length) {
2846 		int size = regions[i].erasesize;
2847 
2848 		/*
2849 		 * Only test sectors that shall not be unlocked. The other
2850 		 * sectors shall be unlocked, so lets keep their locking
2851 		 * status at "unlocked" (locked=0) for the final re-locking.
2852 		 */
2853 		if ((offset < ofs) || (offset >= (ofs + len))) {
2854 			sect[sectors].chip = &cfi->chips[chipnum];
2855 			sect[sectors].adr = adr;
2856 			sect[sectors].locked = do_ppb_xxlock(
2857 				map, &cfi->chips[chipnum], adr, 0,
2858 				DO_XXLOCK_ONEBLOCK_GETLOCK);
2859 		}
2860 
2861 		adr += size;
2862 		offset += size;
2863 		length -= size;
2864 
2865 		if (offset == regions[i].offset + size * regions[i].numblocks)
2866 			i++;
2867 
2868 		if (adr >> cfi->chipshift) {
2869 			if (offset >= (ofs + len))
2870 				break;
2871 			adr = 0;
2872 			chipnum++;
2873 
2874 			if (chipnum >= cfi->numchips)
2875 				break;
2876 		}
2877 
2878 		sectors++;
2879 		if (sectors >= max_sectors) {
2880 			printk(KERN_ERR "Only %d sectors for PPB locking supported!\n",
2881 			       max_sectors);
2882 			kfree(sect);
2883 			return -EINVAL;
2884 		}
2885 	}
2886 
2887 	/* Now unlock the whole chip */
2888 	ret = cfi_varsize_frob(mtd, do_ppb_xxlock, ofs, len,
2889 			       DO_XXLOCK_ONEBLOCK_UNLOCK);
2890 	if (ret) {
2891 		kfree(sect);
2892 		return ret;
2893 	}
2894 
2895 	/*
2896 	 * PPB unlocking always unlocks all sectors of the flash chip.
2897 	 * We need to re-lock all previously locked sectors.
2898 	 */
2899 	for (i = 0; i < sectors; i++) {
2900 		if (sect[i].locked)
2901 			do_ppb_xxlock(map, sect[i].chip, sect[i].adr, 0,
2902 				      DO_XXLOCK_ONEBLOCK_LOCK);
2903 	}
2904 
2905 	kfree(sect);
2906 	return ret;
2907 }
2908 
2909 static int __maybe_unused cfi_ppb_is_locked(struct mtd_info *mtd, loff_t ofs,
2910 					    uint64_t len)
2911 {
2912 	return cfi_varsize_frob(mtd, do_ppb_xxlock, ofs, len,
2913 				DO_XXLOCK_ONEBLOCK_GETLOCK) ? 1 : 0;
2914 }
2915 
2916 static void cfi_amdstd_sync (struct mtd_info *mtd)
2917 {
2918 	struct map_info *map = mtd->priv;
2919 	struct cfi_private *cfi = map->fldrv_priv;
2920 	int i;
2921 	struct flchip *chip;
2922 	int ret = 0;
2923 	DECLARE_WAITQUEUE(wait, current);
2924 
2925 	for (i=0; !ret && i<cfi->numchips; i++) {
2926 		chip = &cfi->chips[i];
2927 
2928 	retry:
2929 		mutex_lock(&chip->mutex);
2930 
2931 		switch(chip->state) {
2932 		case FL_READY:
2933 		case FL_STATUS:
2934 		case FL_CFI_QUERY:
2935 		case FL_JEDEC_QUERY:
2936 			chip->oldstate = chip->state;
2937 			chip->state = FL_SYNCING;
2938 			/* No need to wake_up() on this state change -
2939 			 * as the whole point is that nobody can do anything
2940 			 * with the chip now anyway.
2941 			 */
2942 			fallthrough;
2943 		case FL_SYNCING:
2944 			mutex_unlock(&chip->mutex);
2945 			break;
2946 
2947 		default:
2948 			/* Not an idle state */
2949 			set_current_state(TASK_UNINTERRUPTIBLE);
2950 			add_wait_queue(&chip->wq, &wait);
2951 
2952 			mutex_unlock(&chip->mutex);
2953 
2954 			schedule();
2955 
2956 			remove_wait_queue(&chip->wq, &wait);
2957 
2958 			goto retry;
2959 		}
2960 	}
2961 
2962 	/* Unlock the chips again */
2963 
2964 	for (i--; i >=0; i--) {
2965 		chip = &cfi->chips[i];
2966 
2967 		mutex_lock(&chip->mutex);
2968 
2969 		if (chip->state == FL_SYNCING) {
2970 			chip->state = chip->oldstate;
2971 			wake_up(&chip->wq);
2972 		}
2973 		mutex_unlock(&chip->mutex);
2974 	}
2975 }
2976 
2977 
2978 static int cfi_amdstd_suspend(struct mtd_info *mtd)
2979 {
2980 	struct map_info *map = mtd->priv;
2981 	struct cfi_private *cfi = map->fldrv_priv;
2982 	int i;
2983 	struct flchip *chip;
2984 	int ret = 0;
2985 
2986 	for (i=0; !ret && i<cfi->numchips; i++) {
2987 		chip = &cfi->chips[i];
2988 
2989 		mutex_lock(&chip->mutex);
2990 
2991 		switch(chip->state) {
2992 		case FL_READY:
2993 		case FL_STATUS:
2994 		case FL_CFI_QUERY:
2995 		case FL_JEDEC_QUERY:
2996 			chip->oldstate = chip->state;
2997 			chip->state = FL_PM_SUSPENDED;
2998 			/* No need to wake_up() on this state change -
2999 			 * as the whole point is that nobody can do anything
3000 			 * with the chip now anyway.
3001 			 */
3002 			break;
3003 		case FL_PM_SUSPENDED:
3004 			break;
3005 
3006 		default:
3007 			ret = -EAGAIN;
3008 			break;
3009 		}
3010 		mutex_unlock(&chip->mutex);
3011 	}
3012 
3013 	/* Unlock the chips again */
3014 
3015 	if (ret) {
3016 		for (i--; i >=0; i--) {
3017 			chip = &cfi->chips[i];
3018 
3019 			mutex_lock(&chip->mutex);
3020 
3021 			if (chip->state == FL_PM_SUSPENDED) {
3022 				chip->state = chip->oldstate;
3023 				wake_up(&chip->wq);
3024 			}
3025 			mutex_unlock(&chip->mutex);
3026 		}
3027 	}
3028 
3029 	return ret;
3030 }
3031 
3032 
3033 static void cfi_amdstd_resume(struct mtd_info *mtd)
3034 {
3035 	struct map_info *map = mtd->priv;
3036 	struct cfi_private *cfi = map->fldrv_priv;
3037 	int i;
3038 	struct flchip *chip;
3039 
3040 	for (i=0; i<cfi->numchips; i++) {
3041 
3042 		chip = &cfi->chips[i];
3043 
3044 		mutex_lock(&chip->mutex);
3045 
3046 		if (chip->state == FL_PM_SUSPENDED) {
3047 			chip->state = FL_READY;
3048 			map_write(map, CMD(0xF0), chip->start);
3049 			wake_up(&chip->wq);
3050 		}
3051 		else
3052 			printk(KERN_ERR "Argh. Chip not in PM_SUSPENDED state upon resume()\n");
3053 
3054 		mutex_unlock(&chip->mutex);
3055 	}
3056 }
3057 
3058 
3059 /*
3060  * Ensure that the flash device is put back into read array mode before
3061  * unloading the driver or rebooting.  On some systems, rebooting while
3062  * the flash is in query/program/erase mode will prevent the CPU from
3063  * fetching the bootloader code, requiring a hard reset or power cycle.
3064  */
3065 static int cfi_amdstd_reset(struct mtd_info *mtd)
3066 {
3067 	struct map_info *map = mtd->priv;
3068 	struct cfi_private *cfi = map->fldrv_priv;
3069 	int i, ret;
3070 	struct flchip *chip;
3071 
3072 	for (i = 0; i < cfi->numchips; i++) {
3073 
3074 		chip = &cfi->chips[i];
3075 
3076 		mutex_lock(&chip->mutex);
3077 
3078 		ret = get_chip(map, chip, chip->start, FL_SHUTDOWN);
3079 		if (!ret) {
3080 			map_write(map, CMD(0xF0), chip->start);
3081 			chip->state = FL_SHUTDOWN;
3082 			put_chip(map, chip, chip->start);
3083 		}
3084 
3085 		mutex_unlock(&chip->mutex);
3086 	}
3087 
3088 	return 0;
3089 }
3090 
3091 
3092 static int cfi_amdstd_reboot(struct notifier_block *nb, unsigned long val,
3093 			       void *v)
3094 {
3095 	struct mtd_info *mtd;
3096 
3097 	mtd = container_of(nb, struct mtd_info, reboot_notifier);
3098 	cfi_amdstd_reset(mtd);
3099 	return NOTIFY_DONE;
3100 }
3101 
3102 
3103 static void cfi_amdstd_destroy(struct mtd_info *mtd)
3104 {
3105 	struct map_info *map = mtd->priv;
3106 	struct cfi_private *cfi = map->fldrv_priv;
3107 
3108 	cfi_amdstd_reset(mtd);
3109 	unregister_reboot_notifier(&mtd->reboot_notifier);
3110 	kfree(cfi->cmdset_priv);
3111 	kfree(cfi->cfiq);
3112 	kfree(cfi);
3113 	kfree(mtd->eraseregions);
3114 }
3115 
3116 MODULE_LICENSE("GPL");
3117 MODULE_AUTHOR("Crossnet Co. <info@crossnet.co.jp> et al.");
3118 MODULE_DESCRIPTION("MTD chip driver for AMD/Fujitsu flash chips");
3119 MODULE_ALIAS("cfi_cmdset_0006");
3120 MODULE_ALIAS("cfi_cmdset_0701");
3121