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