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 #define S29GL064N_MN12		0x0c01
52 
53 /*
54  * Status Register bit description. Used by flash devices that don't
55  * support DQ polling (e.g. HyperFlash)
56  */
57 #define CFI_SR_DRB		BIT(7)
58 #define CFI_SR_ESB		BIT(5)
59 #define CFI_SR_PSB		BIT(4)
60 #define CFI_SR_WBASB		BIT(3)
61 #define CFI_SR_SLSB		BIT(1)
62 
63 enum cfi_quirks {
64 	CFI_QUIRK_DQ_TRUE_DATA = BIT(0),
65 };
66 
67 static int cfi_amdstd_read (struct mtd_info *, loff_t, size_t, size_t *, u_char *);
68 static int cfi_amdstd_write_words(struct mtd_info *, loff_t, size_t, size_t *, const u_char *);
69 #if !FORCE_WORD_WRITE
70 static int cfi_amdstd_write_buffers(struct mtd_info *, loff_t, size_t, size_t *, const u_char *);
71 #endif
72 static int cfi_amdstd_erase_chip(struct mtd_info *, struct erase_info *);
73 static int cfi_amdstd_erase_varsize(struct mtd_info *, struct erase_info *);
74 static void cfi_amdstd_sync (struct mtd_info *);
75 static int cfi_amdstd_suspend (struct mtd_info *);
76 static void cfi_amdstd_resume (struct mtd_info *);
77 static int cfi_amdstd_reboot(struct notifier_block *, unsigned long, void *);
78 static int cfi_amdstd_get_fact_prot_info(struct mtd_info *, size_t,
79 					 size_t *, struct otp_info *);
80 static int cfi_amdstd_get_user_prot_info(struct mtd_info *, size_t,
81 					 size_t *, struct otp_info *);
82 static int cfi_amdstd_secsi_read (struct mtd_info *, loff_t, size_t, size_t *, u_char *);
83 static int cfi_amdstd_read_fact_prot_reg(struct mtd_info *, loff_t, size_t,
84 					 size_t *, u_char *);
85 static int cfi_amdstd_read_user_prot_reg(struct mtd_info *, loff_t, size_t,
86 					 size_t *, u_char *);
87 static int cfi_amdstd_write_user_prot_reg(struct mtd_info *, loff_t, size_t,
88 					  size_t *, const u_char *);
89 static int cfi_amdstd_lock_user_prot_reg(struct mtd_info *, loff_t, size_t);
90 
91 static int cfi_amdstd_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
92 				  size_t *retlen, const u_char *buf);
93 
94 static void cfi_amdstd_destroy(struct mtd_info *);
95 
96 struct mtd_info *cfi_cmdset_0002(struct map_info *, int);
97 static struct mtd_info *cfi_amdstd_setup (struct mtd_info *);
98 
99 static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr, int mode);
100 static void put_chip(struct map_info *map, struct flchip *chip, unsigned long adr);
101 #include "fwh_lock.h"
102 
103 static int cfi_atmel_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
104 static int cfi_atmel_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
105 
106 static int cfi_ppb_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
107 static int cfi_ppb_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len);
108 static int cfi_ppb_is_locked(struct mtd_info *mtd, loff_t ofs, uint64_t len);
109 
110 static struct mtd_chip_driver cfi_amdstd_chipdrv = {
111 	.probe		= NULL, /* Not usable directly */
112 	.destroy	= cfi_amdstd_destroy,
113 	.name		= "cfi_cmdset_0002",
114 	.module		= THIS_MODULE
115 };
116 
117 /*
118  * Use status register to poll for Erase/write completion when DQ is not
119  * supported. This is indicated by Bit[1:0] of SoftwareFeatures field in
120  * CFI Primary Vendor-Specific Extended Query table 1.5
121  */
122 static int cfi_use_status_reg(struct cfi_private *cfi)
123 {
124 	struct cfi_pri_amdstd *extp = cfi->cmdset_priv;
125 	u8 poll_mask = CFI_POLL_STATUS_REG | CFI_POLL_DQ;
126 
127 	return extp && extp->MinorVersion >= '5' &&
128 		(extp->SoftwareFeatures & poll_mask) == CFI_POLL_STATUS_REG;
129 }
130 
131 static int cfi_check_err_status(struct map_info *map, struct flchip *chip,
132 				unsigned long adr)
133 {
134 	struct cfi_private *cfi = map->fldrv_priv;
135 	map_word status;
136 
137 	if (!cfi_use_status_reg(cfi))
138 		return 0;
139 
140 	cfi_send_gen_cmd(0x70, cfi->addr_unlock1, chip->start, map, cfi,
141 			 cfi->device_type, NULL);
142 	status = map_read(map, adr);
143 
144 	/* The error bits are invalid while the chip's busy */
145 	if (!map_word_bitsset(map, status, CMD(CFI_SR_DRB)))
146 		return 0;
147 
148 	if (map_word_bitsset(map, status, CMD(0x3a))) {
149 		unsigned long chipstatus = MERGESTATUS(status);
150 
151 		if (chipstatus & CFI_SR_ESB)
152 			pr_err("%s erase operation failed, status %lx\n",
153 			       map->name, chipstatus);
154 		if (chipstatus & CFI_SR_PSB)
155 			pr_err("%s program operation failed, status %lx\n",
156 			       map->name, chipstatus);
157 		if (chipstatus & CFI_SR_WBASB)
158 			pr_err("%s buffer program command aborted, status %lx\n",
159 			       map->name, chipstatus);
160 		if (chipstatus & CFI_SR_SLSB)
161 			pr_err("%s sector write protected, status %lx\n",
162 			       map->name, chipstatus);
163 
164 		/* Erase/Program status bits are set on the operation failure */
165 		if (chipstatus & (CFI_SR_ESB | CFI_SR_PSB))
166 			return 1;
167 	}
168 	return 0;
169 }
170 
171 /* #define DEBUG_CFI_FEATURES */
172 
173 
174 #ifdef DEBUG_CFI_FEATURES
175 static void cfi_tell_features(struct cfi_pri_amdstd *extp)
176 {
177 	const char* erase_suspend[3] = {
178 		"Not supported", "Read only", "Read/write"
179 	};
180 	const char* top_bottom[6] = {
181 		"No WP", "8x8KiB sectors at top & bottom, no WP",
182 		"Bottom boot", "Top boot",
183 		"Uniform, Bottom WP", "Uniform, Top WP"
184 	};
185 
186 	printk("  Silicon revision: %d\n", extp->SiliconRevision >> 1);
187 	printk("  Address sensitive unlock: %s\n",
188 	       (extp->SiliconRevision & 1) ? "Not required" : "Required");
189 
190 	if (extp->EraseSuspend < ARRAY_SIZE(erase_suspend))
191 		printk("  Erase Suspend: %s\n", erase_suspend[extp->EraseSuspend]);
192 	else
193 		printk("  Erase Suspend: Unknown value %d\n", extp->EraseSuspend);
194 
195 	if (extp->BlkProt == 0)
196 		printk("  Block protection: Not supported\n");
197 	else
198 		printk("  Block protection: %d sectors per group\n", extp->BlkProt);
199 
200 
201 	printk("  Temporary block unprotect: %s\n",
202 	       extp->TmpBlkUnprotect ? "Supported" : "Not supported");
203 	printk("  Block protect/unprotect scheme: %d\n", extp->BlkProtUnprot);
204 	printk("  Number of simultaneous operations: %d\n", extp->SimultaneousOps);
205 	printk("  Burst mode: %s\n",
206 	       extp->BurstMode ? "Supported" : "Not supported");
207 	if (extp->PageMode == 0)
208 		printk("  Page mode: Not supported\n");
209 	else
210 		printk("  Page mode: %d word page\n", extp->PageMode << 2);
211 
212 	printk("  Vpp Supply Minimum Program/Erase Voltage: %d.%d V\n",
213 	       extp->VppMin >> 4, extp->VppMin & 0xf);
214 	printk("  Vpp Supply Maximum Program/Erase Voltage: %d.%d V\n",
215 	       extp->VppMax >> 4, extp->VppMax & 0xf);
216 
217 	if (extp->TopBottom < ARRAY_SIZE(top_bottom))
218 		printk("  Top/Bottom Boot Block: %s\n", top_bottom[extp->TopBottom]);
219 	else
220 		printk("  Top/Bottom Boot Block: Unknown value %d\n", extp->TopBottom);
221 }
222 #endif
223 
224 #ifdef AMD_BOOTLOC_BUG
225 /* Wheee. Bring me the head of someone at AMD. */
226 static void fixup_amd_bootblock(struct mtd_info *mtd)
227 {
228 	struct map_info *map = mtd->priv;
229 	struct cfi_private *cfi = map->fldrv_priv;
230 	struct cfi_pri_amdstd *extp = cfi->cmdset_priv;
231 	__u8 major = extp->MajorVersion;
232 	__u8 minor = extp->MinorVersion;
233 
234 	if (((major << 8) | minor) < 0x3131) {
235 		/* CFI version 1.0 => don't trust bootloc */
236 
237 		pr_debug("%s: JEDEC Vendor ID is 0x%02X Device ID is 0x%02X\n",
238 			map->name, cfi->mfr, cfi->id);
239 
240 		/* AFAICS all 29LV400 with a bottom boot block have a device ID
241 		 * of 0x22BA in 16-bit mode and 0xBA in 8-bit mode.
242 		 * These were badly detected as they have the 0x80 bit set
243 		 * so treat them as a special case.
244 		 */
245 		if (((cfi->id == 0xBA) || (cfi->id == 0x22BA)) &&
246 
247 			/* Macronix added CFI to their 2nd generation
248 			 * MX29LV400C B/T but AFAICS no other 29LV400 (AMD,
249 			 * Fujitsu, Spansion, EON, ESI and older Macronix)
250 			 * has CFI.
251 			 *
252 			 * Therefore also check the manufacturer.
253 			 * This reduces the risk of false detection due to
254 			 * the 8-bit device ID.
255 			 */
256 			(cfi->mfr == CFI_MFR_MACRONIX)) {
257 			pr_debug("%s: Macronix MX29LV400C with bottom boot block"
258 				" detected\n", map->name);
259 			extp->TopBottom = 2;	/* bottom boot */
260 		} else
261 		if (cfi->id & 0x80) {
262 			printk(KERN_WARNING "%s: JEDEC Device ID is 0x%02X. Assuming broken CFI table.\n", map->name, cfi->id);
263 			extp->TopBottom = 3;	/* top boot */
264 		} else {
265 			extp->TopBottom = 2;	/* bottom boot */
266 		}
267 
268 		pr_debug("%s: AMD CFI PRI V%c.%c has no boot block field;"
269 			" deduced %s from Device ID\n", map->name, major, minor,
270 			extp->TopBottom == 2 ? "bottom" : "top");
271 	}
272 }
273 #endif
274 
275 #if !FORCE_WORD_WRITE
276 static void fixup_use_write_buffers(struct mtd_info *mtd)
277 {
278 	struct map_info *map = mtd->priv;
279 	struct cfi_private *cfi = map->fldrv_priv;
280 
281 	if (cfi->mfr == CFI_MFR_AMD && cfi->id == 0x2201)
282 		return;
283 
284 	if (cfi->cfiq->BufWriteTimeoutTyp) {
285 		pr_debug("Using buffer write method\n");
286 		mtd->_write = cfi_amdstd_write_buffers;
287 	}
288 }
289 #endif /* !FORCE_WORD_WRITE */
290 
291 /* Atmel chips don't use the same PRI format as AMD chips */
292 static void fixup_convert_atmel_pri(struct mtd_info *mtd)
293 {
294 	struct map_info *map = mtd->priv;
295 	struct cfi_private *cfi = map->fldrv_priv;
296 	struct cfi_pri_amdstd *extp = cfi->cmdset_priv;
297 	struct cfi_pri_atmel atmel_pri;
298 
299 	memcpy(&atmel_pri, extp, sizeof(atmel_pri));
300 	memset((char *)extp + 5, 0, sizeof(*extp) - 5);
301 
302 	if (atmel_pri.Features & 0x02)
303 		extp->EraseSuspend = 2;
304 
305 	/* Some chips got it backwards... */
306 	if (cfi->id == AT49BV6416) {
307 		if (atmel_pri.BottomBoot)
308 			extp->TopBottom = 3;
309 		else
310 			extp->TopBottom = 2;
311 	} else {
312 		if (atmel_pri.BottomBoot)
313 			extp->TopBottom = 2;
314 		else
315 			extp->TopBottom = 3;
316 	}
317 
318 	/* burst write mode not supported */
319 	cfi->cfiq->BufWriteTimeoutTyp = 0;
320 	cfi->cfiq->BufWriteTimeoutMax = 0;
321 }
322 
323 static void fixup_use_secsi(struct mtd_info *mtd)
324 {
325 	/* Setup for chips with a secsi area */
326 	mtd->_read_user_prot_reg = cfi_amdstd_secsi_read;
327 	mtd->_read_fact_prot_reg = cfi_amdstd_secsi_read;
328 }
329 
330 static void fixup_use_erase_chip(struct mtd_info *mtd)
331 {
332 	struct map_info *map = mtd->priv;
333 	struct cfi_private *cfi = map->fldrv_priv;
334 	if ((cfi->cfiq->NumEraseRegions == 1) &&
335 		((cfi->cfiq->EraseRegionInfo[0] & 0xffff) == 0)) {
336 		mtd->_erase = cfi_amdstd_erase_chip;
337 	}
338 
339 }
340 
341 /*
342  * Some Atmel chips (e.g. the AT49BV6416) power-up with all sectors
343  * locked by default.
344  */
345 static void fixup_use_atmel_lock(struct mtd_info *mtd)
346 {
347 	mtd->_lock = cfi_atmel_lock;
348 	mtd->_unlock = cfi_atmel_unlock;
349 	mtd->flags |= MTD_POWERUP_LOCK;
350 }
351 
352 static void fixup_old_sst_eraseregion(struct mtd_info *mtd)
353 {
354 	struct map_info *map = mtd->priv;
355 	struct cfi_private *cfi = map->fldrv_priv;
356 
357 	/*
358 	 * These flashes report two separate eraseblock regions based on the
359 	 * sector_erase-size and block_erase-size, although they both operate on the
360 	 * same memory. This is not allowed according to CFI, so we just pick the
361 	 * sector_erase-size.
362 	 */
363 	cfi->cfiq->NumEraseRegions = 1;
364 }
365 
366 static void fixup_sst39vf(struct mtd_info *mtd)
367 {
368 	struct map_info *map = mtd->priv;
369 	struct cfi_private *cfi = map->fldrv_priv;
370 
371 	fixup_old_sst_eraseregion(mtd);
372 
373 	cfi->addr_unlock1 = 0x5555;
374 	cfi->addr_unlock2 = 0x2AAA;
375 }
376 
377 static void fixup_sst39vf_rev_b(struct mtd_info *mtd)
378 {
379 	struct map_info *map = mtd->priv;
380 	struct cfi_private *cfi = map->fldrv_priv;
381 
382 	fixup_old_sst_eraseregion(mtd);
383 
384 	cfi->addr_unlock1 = 0x555;
385 	cfi->addr_unlock2 = 0x2AA;
386 
387 	cfi->sector_erase_cmd = CMD(0x50);
388 }
389 
390 static void fixup_sst38vf640x_sectorsize(struct mtd_info *mtd)
391 {
392 	struct map_info *map = mtd->priv;
393 	struct cfi_private *cfi = map->fldrv_priv;
394 
395 	fixup_sst39vf_rev_b(mtd);
396 
397 	/*
398 	 * CFI reports 1024 sectors (0x03ff+1) of 64KBytes (0x0100*256) where
399 	 * it should report a size of 8KBytes (0x0020*256).
400 	 */
401 	cfi->cfiq->EraseRegionInfo[0] = 0x002003ff;
402 	pr_warn("%s: Bad 38VF640x CFI data; adjusting sector size from 64 to 8KiB\n",
403 		mtd->name);
404 }
405 
406 static void fixup_s29gl064n_sectors(struct mtd_info *mtd)
407 {
408 	struct map_info *map = mtd->priv;
409 	struct cfi_private *cfi = map->fldrv_priv;
410 
411 	if ((cfi->cfiq->EraseRegionInfo[0] & 0xffff) == 0x003f) {
412 		cfi->cfiq->EraseRegionInfo[0] |= 0x0040;
413 		pr_warn("%s: Bad S29GL064N CFI data; adjust from 64 to 128 sectors\n",
414 			mtd->name);
415 	}
416 }
417 
418 static void fixup_s29gl032n_sectors(struct mtd_info *mtd)
419 {
420 	struct map_info *map = mtd->priv;
421 	struct cfi_private *cfi = map->fldrv_priv;
422 
423 	if ((cfi->cfiq->EraseRegionInfo[1] & 0xffff) == 0x007e) {
424 		cfi->cfiq->EraseRegionInfo[1] &= ~0x0040;
425 		pr_warn("%s: Bad S29GL032N CFI data; adjust from 127 to 63 sectors\n",
426 			mtd->name);
427 	}
428 }
429 
430 static void fixup_s29ns512p_sectors(struct mtd_info *mtd)
431 {
432 	struct map_info *map = mtd->priv;
433 	struct cfi_private *cfi = map->fldrv_priv;
434 
435 	/*
436 	 *  S29NS512P flash uses more than 8bits to report number of sectors,
437 	 * which is not permitted by CFI.
438 	 */
439 	cfi->cfiq->EraseRegionInfo[0] = 0x020001ff;
440 	pr_warn("%s: Bad S29NS512P CFI data; adjust to 512 sectors\n",
441 		mtd->name);
442 }
443 
444 static void fixup_quirks(struct mtd_info *mtd)
445 {
446 	struct map_info *map = mtd->priv;
447 	struct cfi_private *cfi = map->fldrv_priv;
448 
449 	if (cfi->mfr == CFI_MFR_AMD && cfi->id == S29GL064N_MN12)
450 		cfi->quirks |= CFI_QUIRK_DQ_TRUE_DATA;
451 }
452 
453 /* Used to fix CFI-Tables of chips without Extended Query Tables */
454 static struct cfi_fixup cfi_nopri_fixup_table[] = {
455 	{ CFI_MFR_SST, 0x234a, fixup_sst39vf }, /* SST39VF1602 */
456 	{ CFI_MFR_SST, 0x234b, fixup_sst39vf }, /* SST39VF1601 */
457 	{ CFI_MFR_SST, 0x235a, fixup_sst39vf }, /* SST39VF3202 */
458 	{ CFI_MFR_SST, 0x235b, fixup_sst39vf }, /* SST39VF3201 */
459 	{ CFI_MFR_SST, 0x235c, fixup_sst39vf_rev_b }, /* SST39VF3202B */
460 	{ CFI_MFR_SST, 0x235d, fixup_sst39vf_rev_b }, /* SST39VF3201B */
461 	{ CFI_MFR_SST, 0x236c, fixup_sst39vf_rev_b }, /* SST39VF6402B */
462 	{ CFI_MFR_SST, 0x236d, fixup_sst39vf_rev_b }, /* SST39VF6401B */
463 	{ 0, 0, NULL }
464 };
465 
466 static struct cfi_fixup cfi_fixup_table[] = {
467 	{ CFI_MFR_ATMEL, CFI_ID_ANY, fixup_convert_atmel_pri },
468 #ifdef AMD_BOOTLOC_BUG
469 	{ CFI_MFR_AMD, CFI_ID_ANY, fixup_amd_bootblock },
470 	{ CFI_MFR_AMIC, CFI_ID_ANY, fixup_amd_bootblock },
471 	{ CFI_MFR_MACRONIX, CFI_ID_ANY, fixup_amd_bootblock },
472 #endif
473 	{ CFI_MFR_AMD, 0x0050, fixup_use_secsi },
474 	{ CFI_MFR_AMD, 0x0053, fixup_use_secsi },
475 	{ CFI_MFR_AMD, 0x0055, fixup_use_secsi },
476 	{ CFI_MFR_AMD, 0x0056, fixup_use_secsi },
477 	{ CFI_MFR_AMD, 0x005C, fixup_use_secsi },
478 	{ CFI_MFR_AMD, 0x005F, fixup_use_secsi },
479 	{ CFI_MFR_AMD, S29GL064N_MN12, fixup_s29gl064n_sectors },
480 	{ CFI_MFR_AMD, 0x1301, fixup_s29gl064n_sectors },
481 	{ CFI_MFR_AMD, 0x1a00, fixup_s29gl032n_sectors },
482 	{ CFI_MFR_AMD, 0x1a01, fixup_s29gl032n_sectors },
483 	{ CFI_MFR_AMD, 0x3f00, fixup_s29ns512p_sectors },
484 	{ CFI_MFR_SST, 0x536a, fixup_sst38vf640x_sectorsize }, /* SST38VF6402 */
485 	{ CFI_MFR_SST, 0x536b, fixup_sst38vf640x_sectorsize }, /* SST38VF6401 */
486 	{ CFI_MFR_SST, 0x536c, fixup_sst38vf640x_sectorsize }, /* SST38VF6404 */
487 	{ CFI_MFR_SST, 0x536d, fixup_sst38vf640x_sectorsize }, /* SST38VF6403 */
488 #if !FORCE_WORD_WRITE
489 	{ CFI_MFR_ANY, CFI_ID_ANY, fixup_use_write_buffers },
490 #endif
491 	{ CFI_MFR_ANY, CFI_ID_ANY, fixup_quirks },
492 	{ 0, 0, NULL }
493 };
494 static struct cfi_fixup jedec_fixup_table[] = {
495 	{ CFI_MFR_SST, SST49LF004B, fixup_use_fwh_lock },
496 	{ CFI_MFR_SST, SST49LF040B, fixup_use_fwh_lock },
497 	{ CFI_MFR_SST, SST49LF008A, fixup_use_fwh_lock },
498 	{ 0, 0, NULL }
499 };
500 
501 static struct cfi_fixup fixup_table[] = {
502 	/* The CFI vendor ids and the JEDEC vendor IDs appear
503 	 * to be common.  It is like the devices id's are as
504 	 * well.  This table is to pick all cases where
505 	 * we know that is the case.
506 	 */
507 	{ CFI_MFR_ANY, CFI_ID_ANY, fixup_use_erase_chip },
508 	{ CFI_MFR_ATMEL, AT49BV6416, fixup_use_atmel_lock },
509 	{ 0, 0, NULL }
510 };
511 
512 
513 static void cfi_fixup_major_minor(struct cfi_private *cfi,
514 				  struct cfi_pri_amdstd *extp)
515 {
516 	if (cfi->mfr == CFI_MFR_SAMSUNG) {
517 		if ((extp->MajorVersion == '0' && extp->MinorVersion == '0') ||
518 		    (extp->MajorVersion == '3' && extp->MinorVersion == '3')) {
519 			/*
520 			 * Samsung K8P2815UQB and K8D6x16UxM chips
521 			 * report major=0 / minor=0.
522 			 * K8D3x16UxC chips report major=3 / minor=3.
523 			 */
524 			printk(KERN_NOTICE "  Fixing Samsung's Amd/Fujitsu"
525 			       " Extended Query version to 1.%c\n",
526 			       extp->MinorVersion);
527 			extp->MajorVersion = '1';
528 		}
529 	}
530 
531 	/*
532 	 * SST 38VF640x chips report major=0xFF / minor=0xFF.
533 	 */
534 	if (cfi->mfr == CFI_MFR_SST && (cfi->id >> 4) == 0x0536) {
535 		extp->MajorVersion = '1';
536 		extp->MinorVersion = '0';
537 	}
538 }
539 
540 static int is_m29ew(struct cfi_private *cfi)
541 {
542 	if (cfi->mfr == CFI_MFR_INTEL &&
543 	    ((cfi->device_type == CFI_DEVICETYPE_X8 && (cfi->id & 0xff) == 0x7e) ||
544 	     (cfi->device_type == CFI_DEVICETYPE_X16 && cfi->id == 0x227e)))
545 		return 1;
546 	return 0;
547 }
548 
549 /*
550  * From TN-13-07: Patching the Linux Kernel and U-Boot for M29 Flash, page 20:
551  * Some revisions of the M29EW suffer from erase suspend hang ups. In
552  * particular, it can occur when the sequence
553  * Erase Confirm -> Suspend -> Program -> Resume
554  * causes a lockup due to internal timing issues. The consequence is that the
555  * erase cannot be resumed without inserting a dummy command after programming
556  * and prior to resuming. [...] The work-around is to issue a dummy write cycle
557  * that writes an F0 command code before the RESUME command.
558  */
559 static void cfi_fixup_m29ew_erase_suspend(struct map_info *map,
560 					  unsigned long adr)
561 {
562 	struct cfi_private *cfi = map->fldrv_priv;
563 	/* before resume, insert a dummy 0xF0 cycle for Micron M29EW devices */
564 	if (is_m29ew(cfi))
565 		map_write(map, CMD(0xF0), adr);
566 }
567 
568 /*
569  * From TN-13-07: Patching the Linux Kernel and U-Boot for M29 Flash, page 22:
570  *
571  * Some revisions of the M29EW (for example, A1 and A2 step revisions)
572  * are affected by a problem that could cause a hang up when an ERASE SUSPEND
573  * command is issued after an ERASE RESUME operation without waiting for a
574  * minimum delay.  The result is that once the ERASE seems to be completed
575  * (no bits are toggling), the contents of the Flash memory block on which
576  * the erase was ongoing could be inconsistent with the expected values
577  * (typically, the array value is stuck to the 0xC0, 0xC4, 0x80, or 0x84
578  * values), causing a consequent failure of the ERASE operation.
579  * The occurrence of this issue could be high, especially when file system
580  * operations on the Flash are intensive.  As a result, it is recommended
581  * that a patch be applied.  Intensive file system operations can cause many
582  * calls to the garbage routine to free Flash space (also by erasing physical
583  * Flash blocks) and as a result, many consecutive SUSPEND and RESUME
584  * commands can occur.  The problem disappears when a delay is inserted after
585  * the RESUME command by using the udelay() function available in Linux.
586  * The DELAY value must be tuned based on the customer's platform.
587  * The maximum value that fixes the problem in all cases is 500us.
588  * But, in our experience, a delay of 30 µs to 50 µs is sufficient
589  * in most cases.
590  * We have chosen 500µs because this latency is acceptable.
591  */
592 static void cfi_fixup_m29ew_delay_after_resume(struct cfi_private *cfi)
593 {
594 	/*
595 	 * Resolving the Delay After Resume Issue see Micron TN-13-07
596 	 * Worst case delay must be 500µs but 30-50µs should be ok as well
597 	 */
598 	if (is_m29ew(cfi))
599 		cfi_udelay(500);
600 }
601 
602 struct mtd_info *cfi_cmdset_0002(struct map_info *map, int primary)
603 {
604 	struct cfi_private *cfi = map->fldrv_priv;
605 	struct device_node __maybe_unused *np = map->device_node;
606 	struct mtd_info *mtd;
607 	int i;
608 
609 	mtd = kzalloc(sizeof(*mtd), GFP_KERNEL);
610 	if (!mtd)
611 		return NULL;
612 	mtd->priv = map;
613 	mtd->type = MTD_NORFLASH;
614 
615 	/* Fill in the default mtd operations */
616 	mtd->_erase   = cfi_amdstd_erase_varsize;
617 	mtd->_write   = cfi_amdstd_write_words;
618 	mtd->_read    = cfi_amdstd_read;
619 	mtd->_sync    = cfi_amdstd_sync;
620 	mtd->_suspend = cfi_amdstd_suspend;
621 	mtd->_resume  = cfi_amdstd_resume;
622 	mtd->_read_user_prot_reg = cfi_amdstd_read_user_prot_reg;
623 	mtd->_read_fact_prot_reg = cfi_amdstd_read_fact_prot_reg;
624 	mtd->_get_fact_prot_info = cfi_amdstd_get_fact_prot_info;
625 	mtd->_get_user_prot_info = cfi_amdstd_get_user_prot_info;
626 	mtd->_write_user_prot_reg = cfi_amdstd_write_user_prot_reg;
627 	mtd->_lock_user_prot_reg = cfi_amdstd_lock_user_prot_reg;
628 	mtd->flags   = MTD_CAP_NORFLASH;
629 	mtd->name    = map->name;
630 	mtd->writesize = 1;
631 	mtd->writebufsize = cfi_interleave(cfi) << cfi->cfiq->MaxBufWriteSize;
632 
633 	pr_debug("MTD %s(): write buffer size %d\n", __func__,
634 			mtd->writebufsize);
635 
636 	mtd->_panic_write = cfi_amdstd_panic_write;
637 	mtd->reboot_notifier.notifier_call = cfi_amdstd_reboot;
638 
639 	if (cfi->cfi_mode==CFI_MODE_CFI){
640 		unsigned char bootloc;
641 		__u16 adr = primary?cfi->cfiq->P_ADR:cfi->cfiq->A_ADR;
642 		struct cfi_pri_amdstd *extp;
643 
644 		extp = (struct cfi_pri_amdstd*)cfi_read_pri(map, adr, sizeof(*extp), "Amd/Fujitsu");
645 		if (extp) {
646 			/*
647 			 * It's a real CFI chip, not one for which the probe
648 			 * routine faked a CFI structure.
649 			 */
650 			cfi_fixup_major_minor(cfi, extp);
651 
652 			/*
653 			 * Valid primary extension versions are: 1.0, 1.1, 1.2, 1.3, 1.4, 1.5
654 			 * see: http://cs.ozerki.net/zap/pub/axim-x5/docs/cfi_r20.pdf, page 19
655 			 *      http://www.spansion.com/Support/AppNotes/cfi_100_20011201.pdf
656 			 *      http://www.spansion.com/Support/Datasheets/s29ws-p_00_a12_e.pdf
657 			 *      http://www.spansion.com/Support/Datasheets/S29GL_128S_01GS_00_02_e.pdf
658 			 */
659 			if (extp->MajorVersion != '1' ||
660 			    (extp->MajorVersion == '1' && (extp->MinorVersion < '0' || extp->MinorVersion > '5'))) {
661 				printk(KERN_ERR "  Unknown Amd/Fujitsu Extended Query "
662 				       "version %c.%c (%#02x/%#02x).\n",
663 				       extp->MajorVersion, extp->MinorVersion,
664 				       extp->MajorVersion, extp->MinorVersion);
665 				kfree(extp);
666 				kfree(mtd);
667 				return NULL;
668 			}
669 
670 			printk(KERN_INFO "  Amd/Fujitsu Extended Query version %c.%c.\n",
671 			       extp->MajorVersion, extp->MinorVersion);
672 
673 			/* Install our own private info structure */
674 			cfi->cmdset_priv = extp;
675 
676 			/* Apply cfi device specific fixups */
677 			cfi_fixup(mtd, cfi_fixup_table);
678 
679 #ifdef DEBUG_CFI_FEATURES
680 			/* Tell the user about it in lots of lovely detail */
681 			cfi_tell_features(extp);
682 #endif
683 
684 #ifdef CONFIG_OF
685 			if (np && of_property_read_bool(
686 				    np, "use-advanced-sector-protection")
687 			    && extp->BlkProtUnprot == 8) {
688 				printk(KERN_INFO "  Advanced Sector Protection (PPB Locking) supported\n");
689 				mtd->_lock = cfi_ppb_lock;
690 				mtd->_unlock = cfi_ppb_unlock;
691 				mtd->_is_locked = cfi_ppb_is_locked;
692 			}
693 #endif
694 
695 			bootloc = extp->TopBottom;
696 			if ((bootloc < 2) || (bootloc > 5)) {
697 				printk(KERN_WARNING "%s: CFI contains unrecognised boot "
698 				       "bank location (%d). Assuming bottom.\n",
699 				       map->name, bootloc);
700 				bootloc = 2;
701 			}
702 
703 			if (bootloc == 3 && cfi->cfiq->NumEraseRegions > 1) {
704 				printk(KERN_WARNING "%s: Swapping erase regions for top-boot CFI table.\n", map->name);
705 
706 				for (i=0; i<cfi->cfiq->NumEraseRegions / 2; i++) {
707 					int j = (cfi->cfiq->NumEraseRegions-1)-i;
708 
709 					swap(cfi->cfiq->EraseRegionInfo[i],
710 					     cfi->cfiq->EraseRegionInfo[j]);
711 				}
712 			}
713 			/* Set the default CFI lock/unlock addresses */
714 			cfi->addr_unlock1 = 0x555;
715 			cfi->addr_unlock2 = 0x2aa;
716 		}
717 		cfi_fixup(mtd, cfi_nopri_fixup_table);
718 
719 		if (!cfi->addr_unlock1 || !cfi->addr_unlock2) {
720 			kfree(mtd);
721 			return NULL;
722 		}
723 
724 	} /* CFI mode */
725 	else if (cfi->cfi_mode == CFI_MODE_JEDEC) {
726 		/* Apply jedec specific fixups */
727 		cfi_fixup(mtd, jedec_fixup_table);
728 	}
729 	/* Apply generic fixups */
730 	cfi_fixup(mtd, fixup_table);
731 
732 	for (i=0; i< cfi->numchips; i++) {
733 		cfi->chips[i].word_write_time = 1<<cfi->cfiq->WordWriteTimeoutTyp;
734 		cfi->chips[i].buffer_write_time = 1<<cfi->cfiq->BufWriteTimeoutTyp;
735 		cfi->chips[i].erase_time = 1<<cfi->cfiq->BlockEraseTimeoutTyp;
736 		/*
737 		 * First calculate the timeout max according to timeout field
738 		 * of struct cfi_ident that probed from chip's CFI aera, if
739 		 * available. Specify a minimum of 2000us, in case the CFI data
740 		 * is wrong.
741 		 */
742 		if (cfi->cfiq->BufWriteTimeoutTyp &&
743 		    cfi->cfiq->BufWriteTimeoutMax)
744 			cfi->chips[i].buffer_write_time_max =
745 				1 << (cfi->cfiq->BufWriteTimeoutTyp +
746 				      cfi->cfiq->BufWriteTimeoutMax);
747 		else
748 			cfi->chips[i].buffer_write_time_max = 0;
749 
750 		cfi->chips[i].buffer_write_time_max =
751 			max(cfi->chips[i].buffer_write_time_max, 2000);
752 
753 		cfi->chips[i].ref_point_counter = 0;
754 		init_waitqueue_head(&(cfi->chips[i].wq));
755 	}
756 
757 	map->fldrv = &cfi_amdstd_chipdrv;
758 
759 	return cfi_amdstd_setup(mtd);
760 }
761 struct mtd_info *cfi_cmdset_0006(struct map_info *map, int primary) __attribute__((alias("cfi_cmdset_0002")));
762 struct mtd_info *cfi_cmdset_0701(struct map_info *map, int primary) __attribute__((alias("cfi_cmdset_0002")));
763 EXPORT_SYMBOL_GPL(cfi_cmdset_0002);
764 EXPORT_SYMBOL_GPL(cfi_cmdset_0006);
765 EXPORT_SYMBOL_GPL(cfi_cmdset_0701);
766 
767 static struct mtd_info *cfi_amdstd_setup(struct mtd_info *mtd)
768 {
769 	struct map_info *map = mtd->priv;
770 	struct cfi_private *cfi = map->fldrv_priv;
771 	unsigned long devsize = (1<<cfi->cfiq->DevSize) * cfi->interleave;
772 	unsigned long offset = 0;
773 	int i,j;
774 
775 	printk(KERN_NOTICE "number of %s chips: %d\n",
776 	       (cfi->cfi_mode == CFI_MODE_CFI)?"CFI":"JEDEC",cfi->numchips);
777 	/* Select the correct geometry setup */
778 	mtd->size = devsize * cfi->numchips;
779 
780 	mtd->numeraseregions = cfi->cfiq->NumEraseRegions * cfi->numchips;
781 	mtd->eraseregions = kmalloc_array(mtd->numeraseregions,
782 					  sizeof(struct mtd_erase_region_info),
783 					  GFP_KERNEL);
784 	if (!mtd->eraseregions)
785 		goto setup_err;
786 
787 	for (i=0; i<cfi->cfiq->NumEraseRegions; i++) {
788 		unsigned long ernum, ersize;
789 		ersize = ((cfi->cfiq->EraseRegionInfo[i] >> 8) & ~0xff) * cfi->interleave;
790 		ernum = (cfi->cfiq->EraseRegionInfo[i] & 0xffff) + 1;
791 
792 		if (mtd->erasesize < ersize) {
793 			mtd->erasesize = ersize;
794 		}
795 		for (j=0; j<cfi->numchips; j++) {
796 			mtd->eraseregions[(j*cfi->cfiq->NumEraseRegions)+i].offset = (j*devsize)+offset;
797 			mtd->eraseregions[(j*cfi->cfiq->NumEraseRegions)+i].erasesize = ersize;
798 			mtd->eraseregions[(j*cfi->cfiq->NumEraseRegions)+i].numblocks = ernum;
799 		}
800 		offset += (ersize * ernum);
801 	}
802 	if (offset != devsize) {
803 		/* Argh */
804 		printk(KERN_WARNING "Sum of regions (%lx) != total size of set of interleaved chips (%lx)\n", offset, devsize);
805 		goto setup_err;
806 	}
807 
808 	__module_get(THIS_MODULE);
809 	register_reboot_notifier(&mtd->reboot_notifier);
810 	return mtd;
811 
812  setup_err:
813 	kfree(mtd->eraseregions);
814 	kfree(mtd);
815 	kfree(cfi->cmdset_priv);
816 	return NULL;
817 }
818 
819 /*
820  * Return true if the chip is ready and has the correct value.
821  *
822  * Ready is one of: read mode, query mode, erase-suspend-read mode (in any
823  * non-suspended sector) and is indicated by no toggle bits toggling.
824  *
825  * Error are indicated by toggling bits or bits held with the wrong value,
826  * or with bits toggling.
827  *
828  * Note that anything more complicated than checking if no bits are toggling
829  * (including checking DQ5 for an error status) is tricky to get working
830  * correctly and is therefore not done	(particularly with interleaved chips
831  * as each chip must be checked independently of the others).
832  */
833 static int __xipram chip_ready(struct map_info *map, struct flchip *chip,
834 			       unsigned long addr, map_word *expected)
835 {
836 	struct cfi_private *cfi = map->fldrv_priv;
837 	map_word oldd, curd;
838 	int ret;
839 
840 	if (cfi_use_status_reg(cfi)) {
841 		map_word ready = CMD(CFI_SR_DRB);
842 		/*
843 		 * For chips that support status register, check device
844 		 * ready bit
845 		 */
846 		cfi_send_gen_cmd(0x70, cfi->addr_unlock1, chip->start, map, cfi,
847 				 cfi->device_type, NULL);
848 		curd = map_read(map, addr);
849 
850 		return map_word_andequal(map, curd, ready, ready);
851 	}
852 
853 	oldd = map_read(map, addr);
854 	curd = map_read(map, addr);
855 
856 	ret = map_word_equal(map, oldd, curd);
857 
858 	if (!ret || !expected)
859 		return ret;
860 
861 	return map_word_equal(map, curd, *expected);
862 }
863 
864 static int __xipram chip_good(struct map_info *map, struct flchip *chip,
865 			      unsigned long addr, map_word *expected)
866 {
867 	struct cfi_private *cfi = map->fldrv_priv;
868 	map_word *datum = expected;
869 
870 	if (cfi->quirks & CFI_QUIRK_DQ_TRUE_DATA)
871 		datum = NULL;
872 
873 	return chip_ready(map, chip, addr, datum);
874 }
875 
876 static int get_chip(struct map_info *map, struct flchip *chip, unsigned long adr, int mode)
877 {
878 	DECLARE_WAITQUEUE(wait, current);
879 	struct cfi_private *cfi = map->fldrv_priv;
880 	unsigned long timeo;
881 	struct cfi_pri_amdstd *cfip = (struct cfi_pri_amdstd *)cfi->cmdset_priv;
882 
883  resettime:
884 	timeo = jiffies + HZ;
885  retry:
886 	switch (chip->state) {
887 
888 	case FL_STATUS:
889 		for (;;) {
890 			if (chip_ready(map, chip, adr, NULL))
891 				break;
892 
893 			if (time_after(jiffies, timeo)) {
894 				printk(KERN_ERR "Waiting for chip to be ready timed out.\n");
895 				return -EIO;
896 			}
897 			mutex_unlock(&chip->mutex);
898 			cfi_udelay(1);
899 			mutex_lock(&chip->mutex);
900 			/* Someone else might have been playing with it. */
901 			goto retry;
902 		}
903 		return 0;
904 
905 	case FL_READY:
906 	case FL_CFI_QUERY:
907 	case FL_JEDEC_QUERY:
908 		return 0;
909 
910 	case FL_ERASING:
911 		if (!cfip || !(cfip->EraseSuspend & (0x1|0x2)) ||
912 		    !(mode == FL_READY || mode == FL_POINT ||
913 		    (mode == FL_WRITING && (cfip->EraseSuspend & 0x2))))
914 			goto sleep;
915 
916 		/* Do not allow suspend iff read/write to EB address */
917 		if ((adr & chip->in_progress_block_mask) ==
918 		    chip->in_progress_block_addr)
919 			goto sleep;
920 
921 		/* Erase suspend */
922 		/* It's harmless to issue the Erase-Suspend and Erase-Resume
923 		 * commands when the erase algorithm isn't in progress. */
924 		map_write(map, CMD(0xB0), chip->in_progress_block_addr);
925 		chip->oldstate = FL_ERASING;
926 		chip->state = FL_ERASE_SUSPENDING;
927 		chip->erase_suspended = 1;
928 		for (;;) {
929 			if (chip_ready(map, chip, adr, NULL))
930 				break;
931 
932 			if (time_after(jiffies, timeo)) {
933 				/* Should have suspended the erase by now.
934 				 * Send an Erase-Resume command as either
935 				 * there was an error (so leave the erase
936 				 * routine to recover from it) or we trying to
937 				 * use the erase-in-progress sector. */
938 				put_chip(map, chip, adr);
939 				printk(KERN_ERR "MTD %s(): chip not ready after erase suspend\n", __func__);
940 				return -EIO;
941 			}
942 
943 			mutex_unlock(&chip->mutex);
944 			cfi_udelay(1);
945 			mutex_lock(&chip->mutex);
946 			/* Nobody will touch it while it's in state FL_ERASE_SUSPENDING.
947 			   So we can just loop here. */
948 		}
949 		chip->state = FL_READY;
950 		return 0;
951 
952 	case FL_XIP_WHILE_ERASING:
953 		if (mode != FL_READY && mode != FL_POINT &&
954 		    (!cfip || !(cfip->EraseSuspend&2)))
955 			goto sleep;
956 		chip->oldstate = chip->state;
957 		chip->state = FL_READY;
958 		return 0;
959 
960 	case FL_SHUTDOWN:
961 		/* The machine is rebooting */
962 		return -EIO;
963 
964 	case FL_POINT:
965 		/* Only if there's no operation suspended... */
966 		if (mode == FL_READY && chip->oldstate == FL_READY)
967 			return 0;
968 		fallthrough;
969 	default:
970 	sleep:
971 		set_current_state(TASK_UNINTERRUPTIBLE);
972 		add_wait_queue(&chip->wq, &wait);
973 		mutex_unlock(&chip->mutex);
974 		schedule();
975 		remove_wait_queue(&chip->wq, &wait);
976 		mutex_lock(&chip->mutex);
977 		goto resettime;
978 	}
979 }
980 
981 
982 static void put_chip(struct map_info *map, struct flchip *chip, unsigned long adr)
983 {
984 	struct cfi_private *cfi = map->fldrv_priv;
985 
986 	switch(chip->oldstate) {
987 	case FL_ERASING:
988 		cfi_fixup_m29ew_erase_suspend(map,
989 			chip->in_progress_block_addr);
990 		map_write(map, cfi->sector_erase_cmd, chip->in_progress_block_addr);
991 		cfi_fixup_m29ew_delay_after_resume(cfi);
992 		chip->oldstate = FL_READY;
993 		chip->state = FL_ERASING;
994 		break;
995 
996 	case FL_XIP_WHILE_ERASING:
997 		chip->state = chip->oldstate;
998 		chip->oldstate = FL_READY;
999 		break;
1000 
1001 	case FL_READY:
1002 	case FL_STATUS:
1003 		break;
1004 	default:
1005 		printk(KERN_ERR "MTD: put_chip() called with oldstate %d!!\n", chip->oldstate);
1006 	}
1007 	wake_up(&chip->wq);
1008 }
1009 
1010 #ifdef CONFIG_MTD_XIP
1011 
1012 /*
1013  * No interrupt what so ever can be serviced while the flash isn't in array
1014  * mode.  This is ensured by the xip_disable() and xip_enable() functions
1015  * enclosing any code path where the flash is known not to be in array mode.
1016  * And within a XIP disabled code path, only functions marked with __xipram
1017  * may be called and nothing else (it's a good thing to inspect generated
1018  * assembly to make sure inline functions were actually inlined and that gcc
1019  * didn't emit calls to its own support functions). Also configuring MTD CFI
1020  * support to a single buswidth and a single interleave is also recommended.
1021  */
1022 
1023 static void xip_disable(struct map_info *map, struct flchip *chip,
1024 			unsigned long adr)
1025 {
1026 	/* TODO: chips with no XIP use should ignore and return */
1027 	(void) map_read(map, adr); /* ensure mmu mapping is up to date */
1028 	local_irq_disable();
1029 }
1030 
1031 static void __xipram xip_enable(struct map_info *map, struct flchip *chip,
1032 				unsigned long adr)
1033 {
1034 	struct cfi_private *cfi = map->fldrv_priv;
1035 
1036 	if (chip->state != FL_POINT && chip->state != FL_READY) {
1037 		map_write(map, CMD(0xf0), adr);
1038 		chip->state = FL_READY;
1039 	}
1040 	(void) map_read(map, adr);
1041 	xip_iprefetch();
1042 	local_irq_enable();
1043 }
1044 
1045 /*
1046  * When a delay is required for the flash operation to complete, the
1047  * xip_udelay() function is polling for both the given timeout and pending
1048  * (but still masked) hardware interrupts.  Whenever there is an interrupt
1049  * pending then the flash erase operation is suspended, array mode restored
1050  * and interrupts unmasked.  Task scheduling might also happen at that
1051  * point.  The CPU eventually returns from the interrupt or the call to
1052  * schedule() and the suspended flash operation is resumed for the remaining
1053  * of the delay period.
1054  *
1055  * Warning: this function _will_ fool interrupt latency tracing tools.
1056  */
1057 
1058 static void __xipram xip_udelay(struct map_info *map, struct flchip *chip,
1059 				unsigned long adr, int usec)
1060 {
1061 	struct cfi_private *cfi = map->fldrv_priv;
1062 	struct cfi_pri_amdstd *extp = cfi->cmdset_priv;
1063 	map_word status, OK = CMD(0x80);
1064 	unsigned long suspended, start = xip_currtime();
1065 	flstate_t oldstate;
1066 
1067 	do {
1068 		cpu_relax();
1069 		if (xip_irqpending() && extp &&
1070 		    ((chip->state == FL_ERASING && (extp->EraseSuspend & 2))) &&
1071 		    (cfi_interleave_is_1(cfi) || chip->oldstate == FL_READY)) {
1072 			/*
1073 			 * Let's suspend the erase operation when supported.
1074 			 * Note that we currently don't try to suspend
1075 			 * interleaved chips if there is already another
1076 			 * operation suspended (imagine what happens
1077 			 * when one chip was already done with the current
1078 			 * operation while another chip suspended it, then
1079 			 * we resume the whole thing at once).  Yes, it
1080 			 * can happen!
1081 			 */
1082 			map_write(map, CMD(0xb0), adr);
1083 			usec -= xip_elapsed_since(start);
1084 			suspended = xip_currtime();
1085 			do {
1086 				if (xip_elapsed_since(suspended) > 100000) {
1087 					/*
1088 					 * The chip doesn't want to suspend
1089 					 * after waiting for 100 msecs.
1090 					 * This is a critical error but there
1091 					 * is not much we can do here.
1092 					 */
1093 					return;
1094 				}
1095 				status = map_read(map, adr);
1096 			} while (!map_word_andequal(map, status, OK, OK));
1097 
1098 			/* Suspend succeeded */
1099 			oldstate = chip->state;
1100 			if (!map_word_bitsset(map, status, CMD(0x40)))
1101 				break;
1102 			chip->state = FL_XIP_WHILE_ERASING;
1103 			chip->erase_suspended = 1;
1104 			map_write(map, CMD(0xf0), adr);
1105 			(void) map_read(map, adr);
1106 			xip_iprefetch();
1107 			local_irq_enable();
1108 			mutex_unlock(&chip->mutex);
1109 			xip_iprefetch();
1110 			cond_resched();
1111 
1112 			/*
1113 			 * We're back.  However someone else might have
1114 			 * decided to go write to the chip if we are in
1115 			 * a suspended erase state.  If so let's wait
1116 			 * until it's done.
1117 			 */
1118 			mutex_lock(&chip->mutex);
1119 			while (chip->state != FL_XIP_WHILE_ERASING) {
1120 				DECLARE_WAITQUEUE(wait, current);
1121 				set_current_state(TASK_UNINTERRUPTIBLE);
1122 				add_wait_queue(&chip->wq, &wait);
1123 				mutex_unlock(&chip->mutex);
1124 				schedule();
1125 				remove_wait_queue(&chip->wq, &wait);
1126 				mutex_lock(&chip->mutex);
1127 			}
1128 			/* Disallow XIP again */
1129 			local_irq_disable();
1130 
1131 			/* Correct Erase Suspend Hangups for M29EW */
1132 			cfi_fixup_m29ew_erase_suspend(map, adr);
1133 			/* Resume the write or erase operation */
1134 			map_write(map, cfi->sector_erase_cmd, adr);
1135 			chip->state = oldstate;
1136 			start = xip_currtime();
1137 		} else if (usec >= 1000000/HZ) {
1138 			/*
1139 			 * Try to save on CPU power when waiting delay
1140 			 * is at least a system timer tick period.
1141 			 * No need to be extremely accurate here.
1142 			 */
1143 			xip_cpu_idle();
1144 		}
1145 		status = map_read(map, adr);
1146 	} while (!map_word_andequal(map, status, OK, OK)
1147 		 && xip_elapsed_since(start) < usec);
1148 }
1149 
1150 #define UDELAY(map, chip, adr, usec)  xip_udelay(map, chip, adr, usec)
1151 
1152 /*
1153  * The INVALIDATE_CACHED_RANGE() macro is normally used in parallel while
1154  * the flash is actively programming or erasing since we have to poll for
1155  * the operation to complete anyway.  We can't do that in a generic way with
1156  * a XIP setup so do it before the actual flash operation in this case
1157  * and stub it out from INVALIDATE_CACHE_UDELAY.
1158  */
1159 #define XIP_INVAL_CACHED_RANGE(map, from, size)  \
1160 	INVALIDATE_CACHED_RANGE(map, from, size)
1161 
1162 #define INVALIDATE_CACHE_UDELAY(map, chip, adr, len, usec)  \
1163 	UDELAY(map, chip, adr, usec)
1164 
1165 /*
1166  * Extra notes:
1167  *
1168  * Activating this XIP support changes the way the code works a bit.  For
1169  * example the code to suspend the current process when concurrent access
1170  * happens is never executed because xip_udelay() will always return with the
1171  * same chip state as it was entered with.  This is why there is no care for
1172  * the presence of add_wait_queue() or schedule() calls from within a couple
1173  * xip_disable()'d  areas of code, like in do_erase_oneblock for example.
1174  * The queueing and scheduling are always happening within xip_udelay().
1175  *
1176  * Similarly, get_chip() and put_chip() just happen to always be executed
1177  * with chip->state set to FL_READY (or FL_XIP_WHILE_*) where flash state
1178  * is in array mode, therefore never executing many cases therein and not
1179  * causing any problem with XIP.
1180  */
1181 
1182 #else
1183 
1184 #define xip_disable(map, chip, adr)
1185 #define xip_enable(map, chip, adr)
1186 #define XIP_INVAL_CACHED_RANGE(x...)
1187 
1188 #define UDELAY(map, chip, adr, usec)  \
1189 do {  \
1190 	mutex_unlock(&chip->mutex);  \
1191 	cfi_udelay(usec);  \
1192 	mutex_lock(&chip->mutex);  \
1193 } while (0)
1194 
1195 #define INVALIDATE_CACHE_UDELAY(map, chip, adr, len, usec)  \
1196 do {  \
1197 	mutex_unlock(&chip->mutex);  \
1198 	INVALIDATE_CACHED_RANGE(map, adr, len);  \
1199 	cfi_udelay(usec);  \
1200 	mutex_lock(&chip->mutex);  \
1201 } while (0)
1202 
1203 #endif
1204 
1205 static inline int do_read_onechip(struct map_info *map, struct flchip *chip, loff_t adr, size_t len, u_char *buf)
1206 {
1207 	unsigned long cmd_addr;
1208 	struct cfi_private *cfi = map->fldrv_priv;
1209 	int ret;
1210 
1211 	adr += chip->start;
1212 
1213 	/* Ensure cmd read/writes are aligned. */
1214 	cmd_addr = adr & ~(map_bankwidth(map)-1);
1215 
1216 	mutex_lock(&chip->mutex);
1217 	ret = get_chip(map, chip, cmd_addr, FL_READY);
1218 	if (ret) {
1219 		mutex_unlock(&chip->mutex);
1220 		return ret;
1221 	}
1222 
1223 	if (chip->state != FL_POINT && chip->state != FL_READY) {
1224 		map_write(map, CMD(0xf0), cmd_addr);
1225 		chip->state = FL_READY;
1226 	}
1227 
1228 	map_copy_from(map, buf, adr, len);
1229 
1230 	put_chip(map, chip, cmd_addr);
1231 
1232 	mutex_unlock(&chip->mutex);
1233 	return 0;
1234 }
1235 
1236 
1237 static int cfi_amdstd_read (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf)
1238 {
1239 	struct map_info *map = mtd->priv;
1240 	struct cfi_private *cfi = map->fldrv_priv;
1241 	unsigned long ofs;
1242 	int chipnum;
1243 	int ret = 0;
1244 
1245 	/* ofs: offset within the first chip that the first read should start */
1246 	chipnum = (from >> cfi->chipshift);
1247 	ofs = from - (chipnum <<  cfi->chipshift);
1248 
1249 	while (len) {
1250 		unsigned long thislen;
1251 
1252 		if (chipnum >= cfi->numchips)
1253 			break;
1254 
1255 		if ((len + ofs -1) >> cfi->chipshift)
1256 			thislen = (1<<cfi->chipshift) - ofs;
1257 		else
1258 			thislen = len;
1259 
1260 		ret = do_read_onechip(map, &cfi->chips[chipnum], ofs, thislen, buf);
1261 		if (ret)
1262 			break;
1263 
1264 		*retlen += thislen;
1265 		len -= thislen;
1266 		buf += thislen;
1267 
1268 		ofs = 0;
1269 		chipnum++;
1270 	}
1271 	return ret;
1272 }
1273 
1274 typedef int (*otp_op_t)(struct map_info *map, struct flchip *chip,
1275 			loff_t adr, size_t len, u_char *buf, size_t grouplen);
1276 
1277 static inline void otp_enter(struct map_info *map, struct flchip *chip,
1278 			     loff_t adr, size_t len)
1279 {
1280 	struct cfi_private *cfi = map->fldrv_priv;
1281 
1282 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
1283 			 cfi->device_type, NULL);
1284 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
1285 			 cfi->device_type, NULL);
1286 	cfi_send_gen_cmd(0x88, cfi->addr_unlock1, chip->start, map, cfi,
1287 			 cfi->device_type, NULL);
1288 
1289 	INVALIDATE_CACHED_RANGE(map, chip->start + adr, len);
1290 }
1291 
1292 static inline void otp_exit(struct map_info *map, struct flchip *chip,
1293 			    loff_t adr, size_t len)
1294 {
1295 	struct cfi_private *cfi = map->fldrv_priv;
1296 
1297 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
1298 			 cfi->device_type, NULL);
1299 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
1300 			 cfi->device_type, NULL);
1301 	cfi_send_gen_cmd(0x90, cfi->addr_unlock1, chip->start, map, cfi,
1302 			 cfi->device_type, NULL);
1303 	cfi_send_gen_cmd(0x00, cfi->addr_unlock1, chip->start, map, cfi,
1304 			 cfi->device_type, NULL);
1305 
1306 	INVALIDATE_CACHED_RANGE(map, chip->start + adr, len);
1307 }
1308 
1309 static inline int do_read_secsi_onechip(struct map_info *map,
1310 					struct flchip *chip, loff_t adr,
1311 					size_t len, u_char *buf,
1312 					size_t grouplen)
1313 {
1314 	DECLARE_WAITQUEUE(wait, current);
1315 
1316  retry:
1317 	mutex_lock(&chip->mutex);
1318 
1319 	if (chip->state != FL_READY){
1320 		set_current_state(TASK_UNINTERRUPTIBLE);
1321 		add_wait_queue(&chip->wq, &wait);
1322 
1323 		mutex_unlock(&chip->mutex);
1324 
1325 		schedule();
1326 		remove_wait_queue(&chip->wq, &wait);
1327 
1328 		goto retry;
1329 	}
1330 
1331 	adr += chip->start;
1332 
1333 	chip->state = FL_READY;
1334 
1335 	otp_enter(map, chip, adr, len);
1336 	map_copy_from(map, buf, adr, len);
1337 	otp_exit(map, chip, adr, len);
1338 
1339 	wake_up(&chip->wq);
1340 	mutex_unlock(&chip->mutex);
1341 
1342 	return 0;
1343 }
1344 
1345 static int cfi_amdstd_secsi_read (struct mtd_info *mtd, loff_t from, size_t len, size_t *retlen, u_char *buf)
1346 {
1347 	struct map_info *map = mtd->priv;
1348 	struct cfi_private *cfi = map->fldrv_priv;
1349 	unsigned long ofs;
1350 	int chipnum;
1351 	int ret = 0;
1352 
1353 	/* ofs: offset within the first chip that the first read should start */
1354 	/* 8 secsi bytes per chip */
1355 	chipnum=from>>3;
1356 	ofs=from & 7;
1357 
1358 	while (len) {
1359 		unsigned long thislen;
1360 
1361 		if (chipnum >= cfi->numchips)
1362 			break;
1363 
1364 		if ((len + ofs -1) >> 3)
1365 			thislen = (1<<3) - ofs;
1366 		else
1367 			thislen = len;
1368 
1369 		ret = do_read_secsi_onechip(map, &cfi->chips[chipnum], ofs,
1370 					    thislen, buf, 0);
1371 		if (ret)
1372 			break;
1373 
1374 		*retlen += thislen;
1375 		len -= thislen;
1376 		buf += thislen;
1377 
1378 		ofs = 0;
1379 		chipnum++;
1380 	}
1381 	return ret;
1382 }
1383 
1384 static int __xipram do_write_oneword(struct map_info *map, struct flchip *chip,
1385 				     unsigned long adr, map_word datum,
1386 				     int mode);
1387 
1388 static int do_otp_write(struct map_info *map, struct flchip *chip, loff_t adr,
1389 			size_t len, u_char *buf, size_t grouplen)
1390 {
1391 	int ret;
1392 	while (len) {
1393 		unsigned long bus_ofs = adr & ~(map_bankwidth(map)-1);
1394 		int gap = adr - bus_ofs;
1395 		int n = min_t(int, len, map_bankwidth(map) - gap);
1396 		map_word datum = map_word_ff(map);
1397 
1398 		if (n != map_bankwidth(map)) {
1399 			/* partial write of a word, load old contents */
1400 			otp_enter(map, chip, bus_ofs, map_bankwidth(map));
1401 			datum = map_read(map, bus_ofs);
1402 			otp_exit(map, chip, bus_ofs, map_bankwidth(map));
1403 		}
1404 
1405 		datum = map_word_load_partial(map, datum, buf, gap, n);
1406 		ret = do_write_oneword(map, chip, bus_ofs, datum, FL_OTP_WRITE);
1407 		if (ret)
1408 			return ret;
1409 
1410 		adr += n;
1411 		buf += n;
1412 		len -= n;
1413 	}
1414 
1415 	return 0;
1416 }
1417 
1418 static int do_otp_lock(struct map_info *map, struct flchip *chip, loff_t adr,
1419 		       size_t len, u_char *buf, size_t grouplen)
1420 {
1421 	struct cfi_private *cfi = map->fldrv_priv;
1422 	uint8_t lockreg;
1423 	unsigned long timeo;
1424 	int ret;
1425 
1426 	/* make sure area matches group boundaries */
1427 	if ((adr != 0) || (len != grouplen))
1428 		return -EINVAL;
1429 
1430 	mutex_lock(&chip->mutex);
1431 	ret = get_chip(map, chip, chip->start, FL_LOCKING);
1432 	if (ret) {
1433 		mutex_unlock(&chip->mutex);
1434 		return ret;
1435 	}
1436 	chip->state = FL_LOCKING;
1437 
1438 	/* Enter lock register command */
1439 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
1440 			 cfi->device_type, NULL);
1441 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
1442 			 cfi->device_type, NULL);
1443 	cfi_send_gen_cmd(0x40, cfi->addr_unlock1, chip->start, map, cfi,
1444 			 cfi->device_type, NULL);
1445 
1446 	/* read lock register */
1447 	lockreg = cfi_read_query(map, 0);
1448 
1449 	/* set bit 0 to protect extended memory block */
1450 	lockreg &= ~0x01;
1451 
1452 	/* set bit 0 to protect extended memory block */
1453 	/* write lock register */
1454 	map_write(map, CMD(0xA0), chip->start);
1455 	map_write(map, CMD(lockreg), chip->start);
1456 
1457 	/* wait for chip to become ready */
1458 	timeo = jiffies + msecs_to_jiffies(2);
1459 	for (;;) {
1460 		if (chip_ready(map, chip, adr, NULL))
1461 			break;
1462 
1463 		if (time_after(jiffies, timeo)) {
1464 			pr_err("Waiting for chip to be ready timed out.\n");
1465 			ret = -EIO;
1466 			break;
1467 		}
1468 		UDELAY(map, chip, 0, 1);
1469 	}
1470 
1471 	/* exit protection commands */
1472 	map_write(map, CMD(0x90), chip->start);
1473 	map_write(map, CMD(0x00), chip->start);
1474 
1475 	chip->state = FL_READY;
1476 	put_chip(map, chip, chip->start);
1477 	mutex_unlock(&chip->mutex);
1478 
1479 	return ret;
1480 }
1481 
1482 static int cfi_amdstd_otp_walk(struct mtd_info *mtd, loff_t from, size_t len,
1483 			       size_t *retlen, u_char *buf,
1484 			       otp_op_t action, int user_regs)
1485 {
1486 	struct map_info *map = mtd->priv;
1487 	struct cfi_private *cfi = map->fldrv_priv;
1488 	int ofs_factor = cfi->interleave * cfi->device_type;
1489 	unsigned long base;
1490 	int chipnum;
1491 	struct flchip *chip;
1492 	uint8_t otp, lockreg;
1493 	int ret;
1494 
1495 	size_t user_size, factory_size, otpsize;
1496 	loff_t user_offset, factory_offset, otpoffset;
1497 	int user_locked = 0, otplocked;
1498 
1499 	*retlen = 0;
1500 
1501 	for (chipnum = 0; chipnum < cfi->numchips; chipnum++) {
1502 		chip = &cfi->chips[chipnum];
1503 		factory_size = 0;
1504 		user_size = 0;
1505 
1506 		/* Micron M29EW family */
1507 		if (is_m29ew(cfi)) {
1508 			base = chip->start;
1509 
1510 			/* check whether secsi area is factory locked
1511 			   or user lockable */
1512 			mutex_lock(&chip->mutex);
1513 			ret = get_chip(map, chip, base, FL_CFI_QUERY);
1514 			if (ret) {
1515 				mutex_unlock(&chip->mutex);
1516 				return ret;
1517 			}
1518 			cfi_qry_mode_on(base, map, cfi);
1519 			otp = cfi_read_query(map, base + 0x3 * ofs_factor);
1520 			cfi_qry_mode_off(base, map, cfi);
1521 			put_chip(map, chip, base);
1522 			mutex_unlock(&chip->mutex);
1523 
1524 			if (otp & 0x80) {
1525 				/* factory locked */
1526 				factory_offset = 0;
1527 				factory_size = 0x100;
1528 			} else {
1529 				/* customer lockable */
1530 				user_offset = 0;
1531 				user_size = 0x100;
1532 
1533 				mutex_lock(&chip->mutex);
1534 				ret = get_chip(map, chip, base, FL_LOCKING);
1535 				if (ret) {
1536 					mutex_unlock(&chip->mutex);
1537 					return ret;
1538 				}
1539 
1540 				/* Enter lock register command */
1541 				cfi_send_gen_cmd(0xAA, cfi->addr_unlock1,
1542 						 chip->start, map, cfi,
1543 						 cfi->device_type, NULL);
1544 				cfi_send_gen_cmd(0x55, cfi->addr_unlock2,
1545 						 chip->start, map, cfi,
1546 						 cfi->device_type, NULL);
1547 				cfi_send_gen_cmd(0x40, cfi->addr_unlock1,
1548 						 chip->start, map, cfi,
1549 						 cfi->device_type, NULL);
1550 				/* read lock register */
1551 				lockreg = cfi_read_query(map, 0);
1552 				/* exit protection commands */
1553 				map_write(map, CMD(0x90), chip->start);
1554 				map_write(map, CMD(0x00), chip->start);
1555 				put_chip(map, chip, chip->start);
1556 				mutex_unlock(&chip->mutex);
1557 
1558 				user_locked = ((lockreg & 0x01) == 0x00);
1559 			}
1560 		}
1561 
1562 		otpsize = user_regs ? user_size : factory_size;
1563 		if (!otpsize)
1564 			continue;
1565 		otpoffset = user_regs ? user_offset : factory_offset;
1566 		otplocked = user_regs ? user_locked : 1;
1567 
1568 		if (!action) {
1569 			/* return otpinfo */
1570 			struct otp_info *otpinfo;
1571 			len -= sizeof(*otpinfo);
1572 			if (len <= 0)
1573 				return -ENOSPC;
1574 			otpinfo = (struct otp_info *)buf;
1575 			otpinfo->start = from;
1576 			otpinfo->length = otpsize;
1577 			otpinfo->locked = otplocked;
1578 			buf += sizeof(*otpinfo);
1579 			*retlen += sizeof(*otpinfo);
1580 			from += otpsize;
1581 		} else if ((from < otpsize) && (len > 0)) {
1582 			size_t size;
1583 			size = (len < otpsize - from) ? len : otpsize - from;
1584 			ret = action(map, chip, otpoffset + from, size, buf,
1585 				     otpsize);
1586 			if (ret < 0)
1587 				return ret;
1588 
1589 			buf += size;
1590 			len -= size;
1591 			*retlen += size;
1592 			from = 0;
1593 		} else {
1594 			from -= otpsize;
1595 		}
1596 	}
1597 	return 0;
1598 }
1599 
1600 static int cfi_amdstd_get_fact_prot_info(struct mtd_info *mtd, size_t len,
1601 					 size_t *retlen, struct otp_info *buf)
1602 {
1603 	return cfi_amdstd_otp_walk(mtd, 0, len, retlen, (u_char *)buf,
1604 				   NULL, 0);
1605 }
1606 
1607 static int cfi_amdstd_get_user_prot_info(struct mtd_info *mtd, size_t len,
1608 					 size_t *retlen, struct otp_info *buf)
1609 {
1610 	return cfi_amdstd_otp_walk(mtd, 0, len, retlen, (u_char *)buf,
1611 				   NULL, 1);
1612 }
1613 
1614 static int cfi_amdstd_read_fact_prot_reg(struct mtd_info *mtd, loff_t from,
1615 					 size_t len, size_t *retlen,
1616 					 u_char *buf)
1617 {
1618 	return cfi_amdstd_otp_walk(mtd, from, len, retlen,
1619 				   buf, do_read_secsi_onechip, 0);
1620 }
1621 
1622 static int cfi_amdstd_read_user_prot_reg(struct mtd_info *mtd, loff_t from,
1623 					 size_t len, size_t *retlen,
1624 					 u_char *buf)
1625 {
1626 	return cfi_amdstd_otp_walk(mtd, from, len, retlen,
1627 				   buf, do_read_secsi_onechip, 1);
1628 }
1629 
1630 static int cfi_amdstd_write_user_prot_reg(struct mtd_info *mtd, loff_t from,
1631 					  size_t len, size_t *retlen,
1632 					  const u_char *buf)
1633 {
1634 	return cfi_amdstd_otp_walk(mtd, from, len, retlen, (u_char *)buf,
1635 				   do_otp_write, 1);
1636 }
1637 
1638 static int cfi_amdstd_lock_user_prot_reg(struct mtd_info *mtd, loff_t from,
1639 					 size_t len)
1640 {
1641 	size_t retlen;
1642 	return cfi_amdstd_otp_walk(mtd, from, len, &retlen, NULL,
1643 				   do_otp_lock, 1);
1644 }
1645 
1646 static int __xipram do_write_oneword_once(struct map_info *map,
1647 					  struct flchip *chip,
1648 					  unsigned long adr, map_word datum,
1649 					  int mode, struct cfi_private *cfi)
1650 {
1651 	unsigned long timeo;
1652 	/*
1653 	 * We use a 1ms + 1 jiffies generic timeout for writes (most devices
1654 	 * have a max write time of a few hundreds usec). However, we should
1655 	 * use the maximum timeout value given by the chip at probe time
1656 	 * instead.  Unfortunately, struct flchip does have a field for
1657 	 * maximum timeout, only for typical which can be far too short
1658 	 * depending of the conditions.	 The ' + 1' is to avoid having a
1659 	 * timeout of 0 jiffies if HZ is smaller than 1000.
1660 	 */
1661 	unsigned long uWriteTimeout = (HZ / 1000) + 1;
1662 	int ret = 0;
1663 
1664 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
1665 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
1666 	cfi_send_gen_cmd(0xA0, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
1667 	map_write(map, datum, adr);
1668 	chip->state = mode;
1669 
1670 	INVALIDATE_CACHE_UDELAY(map, chip,
1671 				adr, map_bankwidth(map),
1672 				chip->word_write_time);
1673 
1674 	/* See comment above for timeout value. */
1675 	timeo = jiffies + uWriteTimeout;
1676 	for (;;) {
1677 		if (chip->state != mode) {
1678 			/* Someone's suspended the write. Sleep */
1679 			DECLARE_WAITQUEUE(wait, current);
1680 
1681 			set_current_state(TASK_UNINTERRUPTIBLE);
1682 			add_wait_queue(&chip->wq, &wait);
1683 			mutex_unlock(&chip->mutex);
1684 			schedule();
1685 			remove_wait_queue(&chip->wq, &wait);
1686 			timeo = jiffies + (HZ / 2); /* FIXME */
1687 			mutex_lock(&chip->mutex);
1688 			continue;
1689 		}
1690 
1691 		/*
1692 		 * We check "time_after" and "!chip_good" before checking
1693 		 * "chip_good" to avoid the failure due to scheduling.
1694 		 */
1695 		if (time_after(jiffies, timeo) &&
1696 		    !chip_good(map, chip, adr, &datum)) {
1697 			xip_enable(map, chip, adr);
1698 			printk(KERN_WARNING "MTD %s(): software timeout\n", __func__);
1699 			xip_disable(map, chip, adr);
1700 			ret = -EIO;
1701 			break;
1702 		}
1703 
1704 		if (chip_good(map, chip, adr, &datum)) {
1705 			if (cfi_check_err_status(map, chip, adr))
1706 				ret = -EIO;
1707 			break;
1708 		}
1709 
1710 		/* Latency issues. Drop the lock, wait a while and retry */
1711 		UDELAY(map, chip, adr, 1);
1712 	}
1713 
1714 	return ret;
1715 }
1716 
1717 static int __xipram do_write_oneword_start(struct map_info *map,
1718 					   struct flchip *chip,
1719 					   unsigned long adr, int mode)
1720 {
1721 	int ret;
1722 
1723 	mutex_lock(&chip->mutex);
1724 
1725 	ret = get_chip(map, chip, adr, mode);
1726 	if (ret) {
1727 		mutex_unlock(&chip->mutex);
1728 		return ret;
1729 	}
1730 
1731 	if (mode == FL_OTP_WRITE)
1732 		otp_enter(map, chip, adr, map_bankwidth(map));
1733 
1734 	return ret;
1735 }
1736 
1737 static void __xipram do_write_oneword_done(struct map_info *map,
1738 					   struct flchip *chip,
1739 					   unsigned long adr, int mode)
1740 {
1741 	if (mode == FL_OTP_WRITE)
1742 		otp_exit(map, chip, adr, map_bankwidth(map));
1743 
1744 	chip->state = FL_READY;
1745 	DISABLE_VPP(map);
1746 	put_chip(map, chip, adr);
1747 
1748 	mutex_unlock(&chip->mutex);
1749 }
1750 
1751 static int __xipram do_write_oneword_retry(struct map_info *map,
1752 					   struct flchip *chip,
1753 					   unsigned long adr, map_word datum,
1754 					   int mode)
1755 {
1756 	struct cfi_private *cfi = map->fldrv_priv;
1757 	int ret = 0;
1758 	map_word oldd;
1759 	int retry_cnt = 0;
1760 
1761 	/*
1762 	 * Check for a NOP for the case when the datum to write is already
1763 	 * present - it saves time and works around buggy chips that corrupt
1764 	 * data at other locations when 0xff is written to a location that
1765 	 * already contains 0xff.
1766 	 */
1767 	oldd = map_read(map, adr);
1768 	if (map_word_equal(map, oldd, datum)) {
1769 		pr_debug("MTD %s(): NOP\n", __func__);
1770 		return ret;
1771 	}
1772 
1773 	XIP_INVAL_CACHED_RANGE(map, adr, map_bankwidth(map));
1774 	ENABLE_VPP(map);
1775 	xip_disable(map, chip, adr);
1776 
1777  retry:
1778 	ret = do_write_oneword_once(map, chip, adr, datum, mode, cfi);
1779 	if (ret) {
1780 		/* reset on all failures. */
1781 		map_write(map, CMD(0xF0), chip->start);
1782 		/* FIXME - should have reset delay before continuing */
1783 
1784 		if (++retry_cnt <= MAX_RETRIES) {
1785 			ret = 0;
1786 			goto retry;
1787 		}
1788 	}
1789 	xip_enable(map, chip, adr);
1790 
1791 	return ret;
1792 }
1793 
1794 static int __xipram do_write_oneword(struct map_info *map, struct flchip *chip,
1795 				     unsigned long adr, map_word datum,
1796 				     int mode)
1797 {
1798 	int ret;
1799 
1800 	adr += chip->start;
1801 
1802 	pr_debug("MTD %s(): WRITE 0x%.8lx(0x%.8lx)\n", __func__, adr,
1803 		 datum.x[0]);
1804 
1805 	ret = do_write_oneword_start(map, chip, adr, mode);
1806 	if (ret)
1807 		return ret;
1808 
1809 	ret = do_write_oneword_retry(map, chip, adr, datum, mode);
1810 
1811 	do_write_oneword_done(map, chip, adr, mode);
1812 
1813 	return ret;
1814 }
1815 
1816 
1817 static int cfi_amdstd_write_words(struct mtd_info *mtd, loff_t to, size_t len,
1818 				  size_t *retlen, const u_char *buf)
1819 {
1820 	struct map_info *map = mtd->priv;
1821 	struct cfi_private *cfi = map->fldrv_priv;
1822 	int ret;
1823 	int chipnum;
1824 	unsigned long ofs, chipstart;
1825 	DECLARE_WAITQUEUE(wait, current);
1826 
1827 	chipnum = to >> cfi->chipshift;
1828 	ofs = to  - (chipnum << cfi->chipshift);
1829 	chipstart = cfi->chips[chipnum].start;
1830 
1831 	/* If it's not bus-aligned, do the first byte write */
1832 	if (ofs & (map_bankwidth(map)-1)) {
1833 		unsigned long bus_ofs = ofs & ~(map_bankwidth(map)-1);
1834 		int i = ofs - bus_ofs;
1835 		int n = 0;
1836 		map_word tmp_buf;
1837 
1838  retry:
1839 		mutex_lock(&cfi->chips[chipnum].mutex);
1840 
1841 		if (cfi->chips[chipnum].state != FL_READY) {
1842 			set_current_state(TASK_UNINTERRUPTIBLE);
1843 			add_wait_queue(&cfi->chips[chipnum].wq, &wait);
1844 
1845 			mutex_unlock(&cfi->chips[chipnum].mutex);
1846 
1847 			schedule();
1848 			remove_wait_queue(&cfi->chips[chipnum].wq, &wait);
1849 			goto retry;
1850 		}
1851 
1852 		/* Load 'tmp_buf' with old contents of flash */
1853 		tmp_buf = map_read(map, bus_ofs+chipstart);
1854 
1855 		mutex_unlock(&cfi->chips[chipnum].mutex);
1856 
1857 		/* Number of bytes to copy from buffer */
1858 		n = min_t(int, len, map_bankwidth(map)-i);
1859 
1860 		tmp_buf = map_word_load_partial(map, tmp_buf, buf, i, n);
1861 
1862 		ret = do_write_oneword(map, &cfi->chips[chipnum],
1863 				       bus_ofs, tmp_buf, FL_WRITING);
1864 		if (ret)
1865 			return ret;
1866 
1867 		ofs += n;
1868 		buf += n;
1869 		(*retlen) += n;
1870 		len -= n;
1871 
1872 		if (ofs >> cfi->chipshift) {
1873 			chipnum ++;
1874 			ofs = 0;
1875 			if (chipnum == cfi->numchips)
1876 				return 0;
1877 		}
1878 	}
1879 
1880 	/* We are now aligned, write as much as possible */
1881 	while(len >= map_bankwidth(map)) {
1882 		map_word datum;
1883 
1884 		datum = map_word_load(map, buf);
1885 
1886 		ret = do_write_oneword(map, &cfi->chips[chipnum],
1887 				       ofs, datum, FL_WRITING);
1888 		if (ret)
1889 			return ret;
1890 
1891 		ofs += map_bankwidth(map);
1892 		buf += map_bankwidth(map);
1893 		(*retlen) += map_bankwidth(map);
1894 		len -= map_bankwidth(map);
1895 
1896 		if (ofs >> cfi->chipshift) {
1897 			chipnum ++;
1898 			ofs = 0;
1899 			if (chipnum == cfi->numchips)
1900 				return 0;
1901 			chipstart = cfi->chips[chipnum].start;
1902 		}
1903 	}
1904 
1905 	/* Write the trailing bytes if any */
1906 	if (len & (map_bankwidth(map)-1)) {
1907 		map_word tmp_buf;
1908 
1909  retry1:
1910 		mutex_lock(&cfi->chips[chipnum].mutex);
1911 
1912 		if (cfi->chips[chipnum].state != FL_READY) {
1913 			set_current_state(TASK_UNINTERRUPTIBLE);
1914 			add_wait_queue(&cfi->chips[chipnum].wq, &wait);
1915 
1916 			mutex_unlock(&cfi->chips[chipnum].mutex);
1917 
1918 			schedule();
1919 			remove_wait_queue(&cfi->chips[chipnum].wq, &wait);
1920 			goto retry1;
1921 		}
1922 
1923 		tmp_buf = map_read(map, ofs + chipstart);
1924 
1925 		mutex_unlock(&cfi->chips[chipnum].mutex);
1926 
1927 		tmp_buf = map_word_load_partial(map, tmp_buf, buf, 0, len);
1928 
1929 		ret = do_write_oneword(map, &cfi->chips[chipnum],
1930 				       ofs, tmp_buf, FL_WRITING);
1931 		if (ret)
1932 			return ret;
1933 
1934 		(*retlen) += len;
1935 	}
1936 
1937 	return 0;
1938 }
1939 
1940 #if !FORCE_WORD_WRITE
1941 static int __xipram do_write_buffer_wait(struct map_info *map,
1942 					 struct flchip *chip, unsigned long adr,
1943 					 map_word datum)
1944 {
1945 	unsigned long timeo;
1946 	unsigned long u_write_timeout;
1947 	int ret = 0;
1948 
1949 	/*
1950 	 * Timeout is calculated according to CFI data, if available.
1951 	 * See more comments in cfi_cmdset_0002().
1952 	 */
1953 	u_write_timeout = usecs_to_jiffies(chip->buffer_write_time_max);
1954 	timeo = jiffies + u_write_timeout;
1955 
1956 	for (;;) {
1957 		if (chip->state != FL_WRITING) {
1958 			/* Someone's suspended the write. Sleep */
1959 			DECLARE_WAITQUEUE(wait, current);
1960 
1961 			set_current_state(TASK_UNINTERRUPTIBLE);
1962 			add_wait_queue(&chip->wq, &wait);
1963 			mutex_unlock(&chip->mutex);
1964 			schedule();
1965 			remove_wait_queue(&chip->wq, &wait);
1966 			timeo = jiffies + (HZ / 2); /* FIXME */
1967 			mutex_lock(&chip->mutex);
1968 			continue;
1969 		}
1970 
1971 		/*
1972 		 * We check "time_after" and "!chip_good" before checking
1973 		 * "chip_good" to avoid the failure due to scheduling.
1974 		 */
1975 		if (time_after(jiffies, timeo) &&
1976 		    !chip_good(map, chip, adr, &datum)) {
1977 			pr_err("MTD %s(): software timeout, address:0x%.8lx.\n",
1978 			       __func__, adr);
1979 			ret = -EIO;
1980 			break;
1981 		}
1982 
1983 		if (chip_good(map, chip, adr, &datum)) {
1984 			if (cfi_check_err_status(map, chip, adr))
1985 				ret = -EIO;
1986 			break;
1987 		}
1988 
1989 		/* Latency issues. Drop the lock, wait a while and retry */
1990 		UDELAY(map, chip, adr, 1);
1991 	}
1992 
1993 	return ret;
1994 }
1995 
1996 static void __xipram do_write_buffer_reset(struct map_info *map,
1997 					   struct flchip *chip,
1998 					   struct cfi_private *cfi)
1999 {
2000 	/*
2001 	 * Recovery from write-buffer programming failures requires
2002 	 * the write-to-buffer-reset sequence.  Since the last part
2003 	 * of the sequence also works as a normal reset, we can run
2004 	 * the same commands regardless of why we are here.
2005 	 * See e.g.
2006 	 * http://www.spansion.com/Support/Application%20Notes/MirrorBit_Write_Buffer_Prog_Page_Buffer_Read_AN.pdf
2007 	 */
2008 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
2009 			 cfi->device_type, NULL);
2010 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
2011 			 cfi->device_type, NULL);
2012 	cfi_send_gen_cmd(0xF0, cfi->addr_unlock1, chip->start, map, cfi,
2013 			 cfi->device_type, NULL);
2014 
2015 	/* FIXME - should have reset delay before continuing */
2016 }
2017 
2018 /*
2019  * FIXME: interleaved mode not tested, and probably not supported!
2020  */
2021 static int __xipram do_write_buffer(struct map_info *map, struct flchip *chip,
2022 				    unsigned long adr, const u_char *buf,
2023 				    int len)
2024 {
2025 	struct cfi_private *cfi = map->fldrv_priv;
2026 	int ret;
2027 	unsigned long cmd_adr;
2028 	int z, words;
2029 	map_word datum;
2030 
2031 	adr += chip->start;
2032 	cmd_adr = adr;
2033 
2034 	mutex_lock(&chip->mutex);
2035 	ret = get_chip(map, chip, adr, FL_WRITING);
2036 	if (ret) {
2037 		mutex_unlock(&chip->mutex);
2038 		return ret;
2039 	}
2040 
2041 	datum = map_word_load(map, buf);
2042 
2043 	pr_debug("MTD %s(): WRITE 0x%.8lx(0x%.8lx)\n",
2044 		 __func__, adr, datum.x[0]);
2045 
2046 	XIP_INVAL_CACHED_RANGE(map, adr, len);
2047 	ENABLE_VPP(map);
2048 	xip_disable(map, chip, cmd_adr);
2049 
2050 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
2051 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
2052 
2053 	/* Write Buffer Load */
2054 	map_write(map, CMD(0x25), cmd_adr);
2055 
2056 	chip->state = FL_WRITING_TO_BUFFER;
2057 
2058 	/* Write length of data to come */
2059 	words = len / map_bankwidth(map);
2060 	map_write(map, CMD(words - 1), cmd_adr);
2061 	/* Write data */
2062 	z = 0;
2063 	while(z < words * map_bankwidth(map)) {
2064 		datum = map_word_load(map, buf);
2065 		map_write(map, datum, adr + z);
2066 
2067 		z += map_bankwidth(map);
2068 		buf += map_bankwidth(map);
2069 	}
2070 	z -= map_bankwidth(map);
2071 
2072 	adr += z;
2073 
2074 	/* Write Buffer Program Confirm: GO GO GO */
2075 	map_write(map, CMD(0x29), cmd_adr);
2076 	chip->state = FL_WRITING;
2077 
2078 	INVALIDATE_CACHE_UDELAY(map, chip,
2079 				adr, map_bankwidth(map),
2080 				chip->word_write_time);
2081 
2082 	ret = do_write_buffer_wait(map, chip, adr, datum);
2083 	if (ret)
2084 		do_write_buffer_reset(map, chip, cfi);
2085 
2086 	xip_enable(map, chip, adr);
2087 
2088 	chip->state = FL_READY;
2089 	DISABLE_VPP(map);
2090 	put_chip(map, chip, adr);
2091 	mutex_unlock(&chip->mutex);
2092 
2093 	return ret;
2094 }
2095 
2096 
2097 static int cfi_amdstd_write_buffers(struct mtd_info *mtd, loff_t to, size_t len,
2098 				    size_t *retlen, const u_char *buf)
2099 {
2100 	struct map_info *map = mtd->priv;
2101 	struct cfi_private *cfi = map->fldrv_priv;
2102 	int wbufsize = cfi_interleave(cfi) << cfi->cfiq->MaxBufWriteSize;
2103 	int ret;
2104 	int chipnum;
2105 	unsigned long ofs;
2106 
2107 	chipnum = to >> cfi->chipshift;
2108 	ofs = to  - (chipnum << cfi->chipshift);
2109 
2110 	/* If it's not bus-aligned, do the first word write */
2111 	if (ofs & (map_bankwidth(map)-1)) {
2112 		size_t local_len = (-ofs)&(map_bankwidth(map)-1);
2113 		if (local_len > len)
2114 			local_len = len;
2115 		ret = cfi_amdstd_write_words(mtd, ofs + (chipnum<<cfi->chipshift),
2116 					     local_len, retlen, buf);
2117 		if (ret)
2118 			return ret;
2119 		ofs += local_len;
2120 		buf += local_len;
2121 		len -= local_len;
2122 
2123 		if (ofs >> cfi->chipshift) {
2124 			chipnum ++;
2125 			ofs = 0;
2126 			if (chipnum == cfi->numchips)
2127 				return 0;
2128 		}
2129 	}
2130 
2131 	/* Write buffer is worth it only if more than one word to write... */
2132 	while (len >= map_bankwidth(map) * 2) {
2133 		/* We must not cross write block boundaries */
2134 		int size = wbufsize - (ofs & (wbufsize-1));
2135 
2136 		if (size > len)
2137 			size = len;
2138 		if (size % map_bankwidth(map))
2139 			size -= size % map_bankwidth(map);
2140 
2141 		ret = do_write_buffer(map, &cfi->chips[chipnum],
2142 				      ofs, buf, size);
2143 		if (ret)
2144 			return ret;
2145 
2146 		ofs += size;
2147 		buf += size;
2148 		(*retlen) += size;
2149 		len -= size;
2150 
2151 		if (ofs >> cfi->chipshift) {
2152 			chipnum ++;
2153 			ofs = 0;
2154 			if (chipnum == cfi->numchips)
2155 				return 0;
2156 		}
2157 	}
2158 
2159 	if (len) {
2160 		size_t retlen_dregs = 0;
2161 
2162 		ret = cfi_amdstd_write_words(mtd, ofs + (chipnum<<cfi->chipshift),
2163 					     len, &retlen_dregs, buf);
2164 
2165 		*retlen += retlen_dregs;
2166 		return ret;
2167 	}
2168 
2169 	return 0;
2170 }
2171 #endif /* !FORCE_WORD_WRITE */
2172 
2173 /*
2174  * Wait for the flash chip to become ready to write data
2175  *
2176  * This is only called during the panic_write() path. When panic_write()
2177  * is called, the kernel is in the process of a panic, and will soon be
2178  * dead. Therefore we don't take any locks, and attempt to get access
2179  * to the chip as soon as possible.
2180  */
2181 static int cfi_amdstd_panic_wait(struct map_info *map, struct flchip *chip,
2182 				 unsigned long adr)
2183 {
2184 	struct cfi_private *cfi = map->fldrv_priv;
2185 	int retries = 10;
2186 	int i;
2187 
2188 	/*
2189 	 * If the driver thinks the chip is idle, and no toggle bits
2190 	 * are changing, then the chip is actually idle for sure.
2191 	 */
2192 	if (chip->state == FL_READY && chip_ready(map, chip, adr, NULL))
2193 		return 0;
2194 
2195 	/*
2196 	 * Try several times to reset the chip and then wait for it
2197 	 * to become idle. The upper limit of a few milliseconds of
2198 	 * delay isn't a big problem: the kernel is dying anyway. It
2199 	 * is more important to save the messages.
2200 	 */
2201 	while (retries > 0) {
2202 		const unsigned long timeo = (HZ / 1000) + 1;
2203 
2204 		/* send the reset command */
2205 		map_write(map, CMD(0xF0), chip->start);
2206 
2207 		/* wait for the chip to become ready */
2208 		for (i = 0; i < jiffies_to_usecs(timeo); i++) {
2209 			if (chip_ready(map, chip, adr, NULL))
2210 				return 0;
2211 
2212 			udelay(1);
2213 		}
2214 
2215 		retries--;
2216 	}
2217 
2218 	/* the chip never became ready */
2219 	return -EBUSY;
2220 }
2221 
2222 /*
2223  * Write out one word of data to a single flash chip during a kernel panic
2224  *
2225  * This is only called during the panic_write() path. When panic_write()
2226  * is called, the kernel is in the process of a panic, and will soon be
2227  * dead. Therefore we don't take any locks, and attempt to get access
2228  * to the chip as soon as possible.
2229  *
2230  * The implementation of this routine is intentionally similar to
2231  * do_write_oneword(), in order to ease code maintenance.
2232  */
2233 static int do_panic_write_oneword(struct map_info *map, struct flchip *chip,
2234 				  unsigned long adr, map_word datum)
2235 {
2236 	const unsigned long uWriteTimeout = (HZ / 1000) + 1;
2237 	struct cfi_private *cfi = map->fldrv_priv;
2238 	int retry_cnt = 0;
2239 	map_word oldd;
2240 	int ret;
2241 	int i;
2242 
2243 	adr += chip->start;
2244 
2245 	ret = cfi_amdstd_panic_wait(map, chip, adr);
2246 	if (ret)
2247 		return ret;
2248 
2249 	pr_debug("MTD %s(): PANIC WRITE 0x%.8lx(0x%.8lx)\n",
2250 			__func__, adr, datum.x[0]);
2251 
2252 	/*
2253 	 * Check for a NOP for the case when the datum to write is already
2254 	 * present - it saves time and works around buggy chips that corrupt
2255 	 * data at other locations when 0xff is written to a location that
2256 	 * already contains 0xff.
2257 	 */
2258 	oldd = map_read(map, adr);
2259 	if (map_word_equal(map, oldd, datum)) {
2260 		pr_debug("MTD %s(): NOP\n", __func__);
2261 		goto op_done;
2262 	}
2263 
2264 	ENABLE_VPP(map);
2265 
2266 retry:
2267 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
2268 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
2269 	cfi_send_gen_cmd(0xA0, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
2270 	map_write(map, datum, adr);
2271 
2272 	for (i = 0; i < jiffies_to_usecs(uWriteTimeout); i++) {
2273 		if (chip_ready(map, chip, adr, NULL))
2274 			break;
2275 
2276 		udelay(1);
2277 	}
2278 
2279 	if (!chip_ready(map, chip, adr, &datum) ||
2280 	    cfi_check_err_status(map, chip, adr)) {
2281 		/* reset on all failures. */
2282 		map_write(map, CMD(0xF0), chip->start);
2283 		/* FIXME - should have reset delay before continuing */
2284 
2285 		if (++retry_cnt <= MAX_RETRIES)
2286 			goto retry;
2287 
2288 		ret = -EIO;
2289 	}
2290 
2291 op_done:
2292 	DISABLE_VPP(map);
2293 	return ret;
2294 }
2295 
2296 /*
2297  * Write out some data during a kernel panic
2298  *
2299  * This is used by the mtdoops driver to save the dying messages from a
2300  * kernel which has panic'd.
2301  *
2302  * This routine ignores all of the locking used throughout the rest of the
2303  * driver, in order to ensure that the data gets written out no matter what
2304  * state this driver (and the flash chip itself) was in when the kernel crashed.
2305  *
2306  * The implementation of this routine is intentionally similar to
2307  * cfi_amdstd_write_words(), in order to ease code maintenance.
2308  */
2309 static int cfi_amdstd_panic_write(struct mtd_info *mtd, loff_t to, size_t len,
2310 				  size_t *retlen, const u_char *buf)
2311 {
2312 	struct map_info *map = mtd->priv;
2313 	struct cfi_private *cfi = map->fldrv_priv;
2314 	unsigned long ofs, chipstart;
2315 	int ret;
2316 	int chipnum;
2317 
2318 	chipnum = to >> cfi->chipshift;
2319 	ofs = to - (chipnum << cfi->chipshift);
2320 	chipstart = cfi->chips[chipnum].start;
2321 
2322 	/* If it's not bus aligned, do the first byte write */
2323 	if (ofs & (map_bankwidth(map) - 1)) {
2324 		unsigned long bus_ofs = ofs & ~(map_bankwidth(map) - 1);
2325 		int i = ofs - bus_ofs;
2326 		int n = 0;
2327 		map_word tmp_buf;
2328 
2329 		ret = cfi_amdstd_panic_wait(map, &cfi->chips[chipnum], bus_ofs);
2330 		if (ret)
2331 			return ret;
2332 
2333 		/* Load 'tmp_buf' with old contents of flash */
2334 		tmp_buf = map_read(map, bus_ofs + chipstart);
2335 
2336 		/* Number of bytes to copy from buffer */
2337 		n = min_t(int, len, map_bankwidth(map) - i);
2338 
2339 		tmp_buf = map_word_load_partial(map, tmp_buf, buf, i, n);
2340 
2341 		ret = do_panic_write_oneword(map, &cfi->chips[chipnum],
2342 					     bus_ofs, tmp_buf);
2343 		if (ret)
2344 			return ret;
2345 
2346 		ofs += n;
2347 		buf += n;
2348 		(*retlen) += n;
2349 		len -= n;
2350 
2351 		if (ofs >> cfi->chipshift) {
2352 			chipnum++;
2353 			ofs = 0;
2354 			if (chipnum == cfi->numchips)
2355 				return 0;
2356 		}
2357 	}
2358 
2359 	/* We are now aligned, write as much as possible */
2360 	while (len >= map_bankwidth(map)) {
2361 		map_word datum;
2362 
2363 		datum = map_word_load(map, buf);
2364 
2365 		ret = do_panic_write_oneword(map, &cfi->chips[chipnum],
2366 					     ofs, datum);
2367 		if (ret)
2368 			return ret;
2369 
2370 		ofs += map_bankwidth(map);
2371 		buf += map_bankwidth(map);
2372 		(*retlen) += map_bankwidth(map);
2373 		len -= map_bankwidth(map);
2374 
2375 		if (ofs >> cfi->chipshift) {
2376 			chipnum++;
2377 			ofs = 0;
2378 			if (chipnum == cfi->numchips)
2379 				return 0;
2380 
2381 			chipstart = cfi->chips[chipnum].start;
2382 		}
2383 	}
2384 
2385 	/* Write the trailing bytes if any */
2386 	if (len & (map_bankwidth(map) - 1)) {
2387 		map_word tmp_buf;
2388 
2389 		ret = cfi_amdstd_panic_wait(map, &cfi->chips[chipnum], ofs);
2390 		if (ret)
2391 			return ret;
2392 
2393 		tmp_buf = map_read(map, ofs + chipstart);
2394 
2395 		tmp_buf = map_word_load_partial(map, tmp_buf, buf, 0, len);
2396 
2397 		ret = do_panic_write_oneword(map, &cfi->chips[chipnum],
2398 					     ofs, tmp_buf);
2399 		if (ret)
2400 			return ret;
2401 
2402 		(*retlen) += len;
2403 	}
2404 
2405 	return 0;
2406 }
2407 
2408 
2409 /*
2410  * Handle devices with one erase region, that only implement
2411  * the chip erase command.
2412  */
2413 static int __xipram do_erase_chip(struct map_info *map, struct flchip *chip)
2414 {
2415 	struct cfi_private *cfi = map->fldrv_priv;
2416 	unsigned long timeo = jiffies + HZ;
2417 	unsigned long int adr;
2418 	DECLARE_WAITQUEUE(wait, current);
2419 	int ret;
2420 	int retry_cnt = 0;
2421 	map_word datum = map_word_ff(map);
2422 
2423 	adr = cfi->addr_unlock1;
2424 
2425 	mutex_lock(&chip->mutex);
2426 	ret = get_chip(map, chip, adr, FL_ERASING);
2427 	if (ret) {
2428 		mutex_unlock(&chip->mutex);
2429 		return ret;
2430 	}
2431 
2432 	pr_debug("MTD %s(): ERASE 0x%.8lx\n",
2433 	       __func__, chip->start);
2434 
2435 	XIP_INVAL_CACHED_RANGE(map, adr, map->size);
2436 	ENABLE_VPP(map);
2437 	xip_disable(map, chip, adr);
2438 
2439  retry:
2440 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
2441 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
2442 	cfi_send_gen_cmd(0x80, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
2443 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
2444 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
2445 	cfi_send_gen_cmd(0x10, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
2446 
2447 	chip->state = FL_ERASING;
2448 	chip->erase_suspended = 0;
2449 	chip->in_progress_block_addr = adr;
2450 	chip->in_progress_block_mask = ~(map->size - 1);
2451 
2452 	INVALIDATE_CACHE_UDELAY(map, chip,
2453 				adr, map->size,
2454 				chip->erase_time*500);
2455 
2456 	timeo = jiffies + (HZ*20);
2457 
2458 	for (;;) {
2459 		if (chip->state != FL_ERASING) {
2460 			/* Someone's suspended the erase. Sleep */
2461 			set_current_state(TASK_UNINTERRUPTIBLE);
2462 			add_wait_queue(&chip->wq, &wait);
2463 			mutex_unlock(&chip->mutex);
2464 			schedule();
2465 			remove_wait_queue(&chip->wq, &wait);
2466 			mutex_lock(&chip->mutex);
2467 			continue;
2468 		}
2469 		if (chip->erase_suspended) {
2470 			/* This erase was suspended and resumed.
2471 			   Adjust the timeout */
2472 			timeo = jiffies + (HZ*20); /* FIXME */
2473 			chip->erase_suspended = 0;
2474 		}
2475 
2476 		if (chip_ready(map, chip, adr, &datum)) {
2477 			if (cfi_check_err_status(map, chip, adr))
2478 				ret = -EIO;
2479 			break;
2480 		}
2481 
2482 		if (time_after(jiffies, timeo)) {
2483 			printk(KERN_WARNING "MTD %s(): software timeout\n",
2484 			       __func__);
2485 			ret = -EIO;
2486 			break;
2487 		}
2488 
2489 		/* Latency issues. Drop the lock, wait a while and retry */
2490 		UDELAY(map, chip, adr, 1000000/HZ);
2491 	}
2492 	/* Did we succeed? */
2493 	if (ret) {
2494 		/* reset on all failures. */
2495 		map_write(map, CMD(0xF0), chip->start);
2496 		/* FIXME - should have reset delay before continuing */
2497 
2498 		if (++retry_cnt <= MAX_RETRIES) {
2499 			ret = 0;
2500 			goto retry;
2501 		}
2502 	}
2503 
2504 	chip->state = FL_READY;
2505 	xip_enable(map, chip, adr);
2506 	DISABLE_VPP(map);
2507 	put_chip(map, chip, adr);
2508 	mutex_unlock(&chip->mutex);
2509 
2510 	return ret;
2511 }
2512 
2513 
2514 static int __xipram do_erase_oneblock(struct map_info *map, struct flchip *chip, unsigned long adr, int len, void *thunk)
2515 {
2516 	struct cfi_private *cfi = map->fldrv_priv;
2517 	unsigned long timeo = jiffies + HZ;
2518 	DECLARE_WAITQUEUE(wait, current);
2519 	int ret;
2520 	int retry_cnt = 0;
2521 	map_word datum = map_word_ff(map);
2522 
2523 	adr += chip->start;
2524 
2525 	mutex_lock(&chip->mutex);
2526 	ret = get_chip(map, chip, adr, FL_ERASING);
2527 	if (ret) {
2528 		mutex_unlock(&chip->mutex);
2529 		return ret;
2530 	}
2531 
2532 	pr_debug("MTD %s(): ERASE 0x%.8lx\n",
2533 		 __func__, adr);
2534 
2535 	XIP_INVAL_CACHED_RANGE(map, adr, len);
2536 	ENABLE_VPP(map);
2537 	xip_disable(map, chip, adr);
2538 
2539  retry:
2540 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
2541 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
2542 	cfi_send_gen_cmd(0x80, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
2543 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi, cfi->device_type, NULL);
2544 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi, cfi->device_type, NULL);
2545 	map_write(map, cfi->sector_erase_cmd, adr);
2546 
2547 	chip->state = FL_ERASING;
2548 	chip->erase_suspended = 0;
2549 	chip->in_progress_block_addr = adr;
2550 	chip->in_progress_block_mask = ~(len - 1);
2551 
2552 	INVALIDATE_CACHE_UDELAY(map, chip,
2553 				adr, len,
2554 				chip->erase_time*500);
2555 
2556 	timeo = jiffies + (HZ*20);
2557 
2558 	for (;;) {
2559 		if (chip->state != FL_ERASING) {
2560 			/* Someone's suspended the erase. Sleep */
2561 			set_current_state(TASK_UNINTERRUPTIBLE);
2562 			add_wait_queue(&chip->wq, &wait);
2563 			mutex_unlock(&chip->mutex);
2564 			schedule();
2565 			remove_wait_queue(&chip->wq, &wait);
2566 			mutex_lock(&chip->mutex);
2567 			continue;
2568 		}
2569 		if (chip->erase_suspended) {
2570 			/* This erase was suspended and resumed.
2571 			   Adjust the timeout */
2572 			timeo = jiffies + (HZ*20); /* FIXME */
2573 			chip->erase_suspended = 0;
2574 		}
2575 
2576 		if (chip_ready(map, chip, adr, &datum)) {
2577 			if (cfi_check_err_status(map, chip, adr))
2578 				ret = -EIO;
2579 			break;
2580 		}
2581 
2582 		if (time_after(jiffies, timeo)) {
2583 			printk(KERN_WARNING "MTD %s(): software timeout\n",
2584 			       __func__);
2585 			ret = -EIO;
2586 			break;
2587 		}
2588 
2589 		/* Latency issues. Drop the lock, wait a while and retry */
2590 		UDELAY(map, chip, adr, 1000000/HZ);
2591 	}
2592 	/* Did we succeed? */
2593 	if (ret) {
2594 		/* reset on all failures. */
2595 		map_write(map, CMD(0xF0), chip->start);
2596 		/* FIXME - should have reset delay before continuing */
2597 
2598 		if (++retry_cnt <= MAX_RETRIES) {
2599 			ret = 0;
2600 			goto retry;
2601 		}
2602 	}
2603 
2604 	chip->state = FL_READY;
2605 	xip_enable(map, chip, adr);
2606 	DISABLE_VPP(map);
2607 	put_chip(map, chip, adr);
2608 	mutex_unlock(&chip->mutex);
2609 	return ret;
2610 }
2611 
2612 
2613 static int cfi_amdstd_erase_varsize(struct mtd_info *mtd, struct erase_info *instr)
2614 {
2615 	return cfi_varsize_frob(mtd, do_erase_oneblock, instr->addr,
2616 				instr->len, NULL);
2617 }
2618 
2619 
2620 static int cfi_amdstd_erase_chip(struct mtd_info *mtd, struct erase_info *instr)
2621 {
2622 	struct map_info *map = mtd->priv;
2623 	struct cfi_private *cfi = map->fldrv_priv;
2624 
2625 	if (instr->addr != 0)
2626 		return -EINVAL;
2627 
2628 	if (instr->len != mtd->size)
2629 		return -EINVAL;
2630 
2631 	return do_erase_chip(map, &cfi->chips[0]);
2632 }
2633 
2634 static int do_atmel_lock(struct map_info *map, struct flchip *chip,
2635 			 unsigned long adr, int len, void *thunk)
2636 {
2637 	struct cfi_private *cfi = map->fldrv_priv;
2638 	int ret;
2639 
2640 	mutex_lock(&chip->mutex);
2641 	ret = get_chip(map, chip, adr + chip->start, FL_LOCKING);
2642 	if (ret)
2643 		goto out_unlock;
2644 	chip->state = FL_LOCKING;
2645 
2646 	pr_debug("MTD %s(): LOCK 0x%08lx len %d\n", __func__, adr, len);
2647 
2648 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
2649 			 cfi->device_type, NULL);
2650 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
2651 			 cfi->device_type, NULL);
2652 	cfi_send_gen_cmd(0x80, cfi->addr_unlock1, chip->start, map, cfi,
2653 			 cfi->device_type, NULL);
2654 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
2655 			 cfi->device_type, NULL);
2656 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
2657 			 cfi->device_type, NULL);
2658 	map_write(map, CMD(0x40), chip->start + adr);
2659 
2660 	chip->state = FL_READY;
2661 	put_chip(map, chip, adr + chip->start);
2662 	ret = 0;
2663 
2664 out_unlock:
2665 	mutex_unlock(&chip->mutex);
2666 	return ret;
2667 }
2668 
2669 static int do_atmel_unlock(struct map_info *map, struct flchip *chip,
2670 			   unsigned long adr, int len, void *thunk)
2671 {
2672 	struct cfi_private *cfi = map->fldrv_priv;
2673 	int ret;
2674 
2675 	mutex_lock(&chip->mutex);
2676 	ret = get_chip(map, chip, adr + chip->start, FL_UNLOCKING);
2677 	if (ret)
2678 		goto out_unlock;
2679 	chip->state = FL_UNLOCKING;
2680 
2681 	pr_debug("MTD %s(): LOCK 0x%08lx len %d\n", __func__, adr, len);
2682 
2683 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
2684 			 cfi->device_type, NULL);
2685 	map_write(map, CMD(0x70), adr);
2686 
2687 	chip->state = FL_READY;
2688 	put_chip(map, chip, adr + chip->start);
2689 	ret = 0;
2690 
2691 out_unlock:
2692 	mutex_unlock(&chip->mutex);
2693 	return ret;
2694 }
2695 
2696 static int cfi_atmel_lock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
2697 {
2698 	return cfi_varsize_frob(mtd, do_atmel_lock, ofs, len, NULL);
2699 }
2700 
2701 static int cfi_atmel_unlock(struct mtd_info *mtd, loff_t ofs, uint64_t len)
2702 {
2703 	return cfi_varsize_frob(mtd, do_atmel_unlock, ofs, len, NULL);
2704 }
2705 
2706 /*
2707  * Advanced Sector Protection - PPB (Persistent Protection Bit) locking
2708  */
2709 
2710 struct ppb_lock {
2711 	struct flchip *chip;
2712 	unsigned long adr;
2713 	int locked;
2714 };
2715 
2716 #define DO_XXLOCK_ONEBLOCK_LOCK		((void *)1)
2717 #define DO_XXLOCK_ONEBLOCK_UNLOCK	((void *)2)
2718 #define DO_XXLOCK_ONEBLOCK_GETLOCK	((void *)3)
2719 
2720 static int __maybe_unused do_ppb_xxlock(struct map_info *map,
2721 					struct flchip *chip,
2722 					unsigned long adr, int len, void *thunk)
2723 {
2724 	struct cfi_private *cfi = map->fldrv_priv;
2725 	unsigned long timeo;
2726 	int ret;
2727 
2728 	adr += chip->start;
2729 	mutex_lock(&chip->mutex);
2730 	ret = get_chip(map, chip, adr, FL_LOCKING);
2731 	if (ret) {
2732 		mutex_unlock(&chip->mutex);
2733 		return ret;
2734 	}
2735 
2736 	pr_debug("MTD %s(): XXLOCK 0x%08lx len %d\n", __func__, adr, len);
2737 
2738 	cfi_send_gen_cmd(0xAA, cfi->addr_unlock1, chip->start, map, cfi,
2739 			 cfi->device_type, NULL);
2740 	cfi_send_gen_cmd(0x55, cfi->addr_unlock2, chip->start, map, cfi,
2741 			 cfi->device_type, NULL);
2742 	/* PPB entry command */
2743 	cfi_send_gen_cmd(0xC0, cfi->addr_unlock1, chip->start, map, cfi,
2744 			 cfi->device_type, NULL);
2745 
2746 	if (thunk == DO_XXLOCK_ONEBLOCK_LOCK) {
2747 		chip->state = FL_LOCKING;
2748 		map_write(map, CMD(0xA0), adr);
2749 		map_write(map, CMD(0x00), adr);
2750 	} else if (thunk == DO_XXLOCK_ONEBLOCK_UNLOCK) {
2751 		/*
2752 		 * Unlocking of one specific sector is not supported, so we
2753 		 * have to unlock all sectors of this device instead
2754 		 */
2755 		chip->state = FL_UNLOCKING;
2756 		map_write(map, CMD(0x80), chip->start);
2757 		map_write(map, CMD(0x30), chip->start);
2758 	} else if (thunk == DO_XXLOCK_ONEBLOCK_GETLOCK) {
2759 		chip->state = FL_JEDEC_QUERY;
2760 		/* Return locked status: 0->locked, 1->unlocked */
2761 		ret = !cfi_read_query(map, adr);
2762 	} else
2763 		BUG();
2764 
2765 	/*
2766 	 * Wait for some time as unlocking of all sectors takes quite long
2767 	 */
2768 	timeo = jiffies + msecs_to_jiffies(2000);	/* 2s max (un)locking */
2769 	for (;;) {
2770 		if (chip_ready(map, chip, adr, NULL))
2771 			break;
2772 
2773 		if (time_after(jiffies, timeo)) {
2774 			printk(KERN_ERR "Waiting for chip to be ready timed out.\n");
2775 			ret = -EIO;
2776 			break;
2777 		}
2778 
2779 		UDELAY(map, chip, adr, 1);
2780 	}
2781 
2782 	/* Exit BC commands */
2783 	map_write(map, CMD(0x90), chip->start);
2784 	map_write(map, CMD(0x00), chip->start);
2785 
2786 	chip->state = FL_READY;
2787 	put_chip(map, chip, adr);
2788 	mutex_unlock(&chip->mutex);
2789 
2790 	return ret;
2791 }
2792 
2793 static int __maybe_unused cfi_ppb_lock(struct mtd_info *mtd, loff_t ofs,
2794 				       uint64_t len)
2795 {
2796 	return cfi_varsize_frob(mtd, do_ppb_xxlock, ofs, len,
2797 				DO_XXLOCK_ONEBLOCK_LOCK);
2798 }
2799 
2800 static int __maybe_unused cfi_ppb_unlock(struct mtd_info *mtd, loff_t ofs,
2801 					 uint64_t len)
2802 {
2803 	struct mtd_erase_region_info *regions = mtd->eraseregions;
2804 	struct map_info *map = mtd->priv;
2805 	struct cfi_private *cfi = map->fldrv_priv;
2806 	struct ppb_lock *sect;
2807 	unsigned long adr;
2808 	loff_t offset;
2809 	uint64_t length;
2810 	int chipnum;
2811 	int i;
2812 	int sectors;
2813 	int ret;
2814 	int max_sectors;
2815 
2816 	/*
2817 	 * PPB unlocking always unlocks all sectors of the flash chip.
2818 	 * We need to re-lock all previously locked sectors. So lets
2819 	 * first check the locking status of all sectors and save
2820 	 * it for future use.
2821 	 */
2822 	max_sectors = 0;
2823 	for (i = 0; i < mtd->numeraseregions; i++)
2824 		max_sectors += regions[i].numblocks;
2825 
2826 	sect = kcalloc(max_sectors, sizeof(struct ppb_lock), GFP_KERNEL);
2827 	if (!sect)
2828 		return -ENOMEM;
2829 
2830 	/*
2831 	 * This code to walk all sectors is a slightly modified version
2832 	 * of the cfi_varsize_frob() code.
2833 	 */
2834 	i = 0;
2835 	chipnum = 0;
2836 	adr = 0;
2837 	sectors = 0;
2838 	offset = 0;
2839 	length = mtd->size;
2840 
2841 	while (length) {
2842 		int size = regions[i].erasesize;
2843 
2844 		/*
2845 		 * Only test sectors that shall not be unlocked. The other
2846 		 * sectors shall be unlocked, so lets keep their locking
2847 		 * status at "unlocked" (locked=0) for the final re-locking.
2848 		 */
2849 		if ((offset < ofs) || (offset >= (ofs + len))) {
2850 			sect[sectors].chip = &cfi->chips[chipnum];
2851 			sect[sectors].adr = adr;
2852 			sect[sectors].locked = do_ppb_xxlock(
2853 				map, &cfi->chips[chipnum], adr, 0,
2854 				DO_XXLOCK_ONEBLOCK_GETLOCK);
2855 		}
2856 
2857 		adr += size;
2858 		offset += size;
2859 		length -= size;
2860 
2861 		if (offset == regions[i].offset + size * regions[i].numblocks)
2862 			i++;
2863 
2864 		if (adr >> cfi->chipshift) {
2865 			if (offset >= (ofs + len))
2866 				break;
2867 			adr = 0;
2868 			chipnum++;
2869 
2870 			if (chipnum >= cfi->numchips)
2871 				break;
2872 		}
2873 
2874 		sectors++;
2875 		if (sectors >= max_sectors) {
2876 			printk(KERN_ERR "Only %d sectors for PPB locking supported!\n",
2877 			       max_sectors);
2878 			kfree(sect);
2879 			return -EINVAL;
2880 		}
2881 	}
2882 
2883 	/* Now unlock the whole chip */
2884 	ret = cfi_varsize_frob(mtd, do_ppb_xxlock, ofs, len,
2885 			       DO_XXLOCK_ONEBLOCK_UNLOCK);
2886 	if (ret) {
2887 		kfree(sect);
2888 		return ret;
2889 	}
2890 
2891 	/*
2892 	 * PPB unlocking always unlocks all sectors of the flash chip.
2893 	 * We need to re-lock all previously locked sectors.
2894 	 */
2895 	for (i = 0; i < sectors; i++) {
2896 		if (sect[i].locked)
2897 			do_ppb_xxlock(map, sect[i].chip, sect[i].adr, 0,
2898 				      DO_XXLOCK_ONEBLOCK_LOCK);
2899 	}
2900 
2901 	kfree(sect);
2902 	return ret;
2903 }
2904 
2905 static int __maybe_unused cfi_ppb_is_locked(struct mtd_info *mtd, loff_t ofs,
2906 					    uint64_t len)
2907 {
2908 	return cfi_varsize_frob(mtd, do_ppb_xxlock, ofs, len,
2909 				DO_XXLOCK_ONEBLOCK_GETLOCK) ? 1 : 0;
2910 }
2911 
2912 static void cfi_amdstd_sync (struct mtd_info *mtd)
2913 {
2914 	struct map_info *map = mtd->priv;
2915 	struct cfi_private *cfi = map->fldrv_priv;
2916 	int i;
2917 	struct flchip *chip;
2918 	int ret = 0;
2919 	DECLARE_WAITQUEUE(wait, current);
2920 
2921 	for (i=0; !ret && i<cfi->numchips; i++) {
2922 		chip = &cfi->chips[i];
2923 
2924 	retry:
2925 		mutex_lock(&chip->mutex);
2926 
2927 		switch(chip->state) {
2928 		case FL_READY:
2929 		case FL_STATUS:
2930 		case FL_CFI_QUERY:
2931 		case FL_JEDEC_QUERY:
2932 			chip->oldstate = chip->state;
2933 			chip->state = FL_SYNCING;
2934 			/* No need to wake_up() on this state change -
2935 			 * as the whole point is that nobody can do anything
2936 			 * with the chip now anyway.
2937 			 */
2938 			fallthrough;
2939 		case FL_SYNCING:
2940 			mutex_unlock(&chip->mutex);
2941 			break;
2942 
2943 		default:
2944 			/* Not an idle state */
2945 			set_current_state(TASK_UNINTERRUPTIBLE);
2946 			add_wait_queue(&chip->wq, &wait);
2947 
2948 			mutex_unlock(&chip->mutex);
2949 
2950 			schedule();
2951 
2952 			remove_wait_queue(&chip->wq, &wait);
2953 
2954 			goto retry;
2955 		}
2956 	}
2957 
2958 	/* Unlock the chips again */
2959 
2960 	for (i--; i >=0; i--) {
2961 		chip = &cfi->chips[i];
2962 
2963 		mutex_lock(&chip->mutex);
2964 
2965 		if (chip->state == FL_SYNCING) {
2966 			chip->state = chip->oldstate;
2967 			wake_up(&chip->wq);
2968 		}
2969 		mutex_unlock(&chip->mutex);
2970 	}
2971 }
2972 
2973 
2974 static int cfi_amdstd_suspend(struct mtd_info *mtd)
2975 {
2976 	struct map_info *map = mtd->priv;
2977 	struct cfi_private *cfi = map->fldrv_priv;
2978 	int i;
2979 	struct flchip *chip;
2980 	int ret = 0;
2981 
2982 	for (i=0; !ret && i<cfi->numchips; i++) {
2983 		chip = &cfi->chips[i];
2984 
2985 		mutex_lock(&chip->mutex);
2986 
2987 		switch(chip->state) {
2988 		case FL_READY:
2989 		case FL_STATUS:
2990 		case FL_CFI_QUERY:
2991 		case FL_JEDEC_QUERY:
2992 			chip->oldstate = chip->state;
2993 			chip->state = FL_PM_SUSPENDED;
2994 			/* No need to wake_up() on this state change -
2995 			 * as the whole point is that nobody can do anything
2996 			 * with the chip now anyway.
2997 			 */
2998 			break;
2999 		case FL_PM_SUSPENDED:
3000 			break;
3001 
3002 		default:
3003 			ret = -EAGAIN;
3004 			break;
3005 		}
3006 		mutex_unlock(&chip->mutex);
3007 	}
3008 
3009 	/* Unlock the chips again */
3010 
3011 	if (ret) {
3012 		for (i--; i >=0; i--) {
3013 			chip = &cfi->chips[i];
3014 
3015 			mutex_lock(&chip->mutex);
3016 
3017 			if (chip->state == FL_PM_SUSPENDED) {
3018 				chip->state = chip->oldstate;
3019 				wake_up(&chip->wq);
3020 			}
3021 			mutex_unlock(&chip->mutex);
3022 		}
3023 	}
3024 
3025 	return ret;
3026 }
3027 
3028 
3029 static void cfi_amdstd_resume(struct mtd_info *mtd)
3030 {
3031 	struct map_info *map = mtd->priv;
3032 	struct cfi_private *cfi = map->fldrv_priv;
3033 	int i;
3034 	struct flchip *chip;
3035 
3036 	for (i=0; i<cfi->numchips; i++) {
3037 
3038 		chip = &cfi->chips[i];
3039 
3040 		mutex_lock(&chip->mutex);
3041 
3042 		if (chip->state == FL_PM_SUSPENDED) {
3043 			chip->state = FL_READY;
3044 			map_write(map, CMD(0xF0), chip->start);
3045 			wake_up(&chip->wq);
3046 		}
3047 		else
3048 			printk(KERN_ERR "Argh. Chip not in PM_SUSPENDED state upon resume()\n");
3049 
3050 		mutex_unlock(&chip->mutex);
3051 	}
3052 }
3053 
3054 
3055 /*
3056  * Ensure that the flash device is put back into read array mode before
3057  * unloading the driver or rebooting.  On some systems, rebooting while
3058  * the flash is in query/program/erase mode will prevent the CPU from
3059  * fetching the bootloader code, requiring a hard reset or power cycle.
3060  */
3061 static int cfi_amdstd_reset(struct mtd_info *mtd)
3062 {
3063 	struct map_info *map = mtd->priv;
3064 	struct cfi_private *cfi = map->fldrv_priv;
3065 	int i, ret;
3066 	struct flchip *chip;
3067 
3068 	for (i = 0; i < cfi->numchips; i++) {
3069 
3070 		chip = &cfi->chips[i];
3071 
3072 		mutex_lock(&chip->mutex);
3073 
3074 		ret = get_chip(map, chip, chip->start, FL_SHUTDOWN);
3075 		if (!ret) {
3076 			map_write(map, CMD(0xF0), chip->start);
3077 			chip->state = FL_SHUTDOWN;
3078 			put_chip(map, chip, chip->start);
3079 		}
3080 
3081 		mutex_unlock(&chip->mutex);
3082 	}
3083 
3084 	return 0;
3085 }
3086 
3087 
3088 static int cfi_amdstd_reboot(struct notifier_block *nb, unsigned long val,
3089 			       void *v)
3090 {
3091 	struct mtd_info *mtd;
3092 
3093 	mtd = container_of(nb, struct mtd_info, reboot_notifier);
3094 	cfi_amdstd_reset(mtd);
3095 	return NOTIFY_DONE;
3096 }
3097 
3098 
3099 static void cfi_amdstd_destroy(struct mtd_info *mtd)
3100 {
3101 	struct map_info *map = mtd->priv;
3102 	struct cfi_private *cfi = map->fldrv_priv;
3103 
3104 	cfi_amdstd_reset(mtd);
3105 	unregister_reboot_notifier(&mtd->reboot_notifier);
3106 	kfree(cfi->cmdset_priv);
3107 	kfree(cfi->cfiq);
3108 	kfree(cfi);
3109 	kfree(mtd->eraseregions);
3110 }
3111 
3112 MODULE_LICENSE("GPL");
3113 MODULE_AUTHOR("Crossnet Co. <info@crossnet.co.jp> et al.");
3114 MODULE_DESCRIPTION("MTD chip driver for AMD/Fujitsu flash chips");
3115 MODULE_ALIAS("cfi_cmdset_0006");
3116 MODULE_ALIAS("cfi_cmdset_0701");
3117