Linux-libre 5.3.12-gnu
[librecmc/linux-libre.git] / drivers / mtd / nand / raw / nand_legacy.c
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  Copyright (C) 2000 Steven J. Hill (sjhill@realitydiluted.com)
4  *                2002-2006 Thomas Gleixner (tglx@linutronix.de)
5  *
6  *  Credits:
7  *      David Woodhouse for adding multichip support
8  *
9  *      Aleph One Ltd. and Toby Churchill Ltd. for supporting the
10  *      rework for 2K page size chips
11  *
12  * This file contains all legacy helpers/code that should be removed
13  * at some point.
14  */
15
16 #include <linux/delay.h>
17 #include <linux/io.h>
18 #include <linux/nmi.h>
19
20 #include "internals.h"
21
22 /**
23  * nand_read_byte - [DEFAULT] read one byte from the chip
24  * @chip: NAND chip object
25  *
26  * Default read function for 8bit buswidth
27  */
28 static uint8_t nand_read_byte(struct nand_chip *chip)
29 {
30         return readb(chip->legacy.IO_ADDR_R);
31 }
32
33 /**
34  * nand_read_byte16 - [DEFAULT] read one byte endianness aware from the chip
35  * @chip: NAND chip object
36  *
37  * Default read function for 16bit buswidth with endianness conversion.
38  *
39  */
40 static uint8_t nand_read_byte16(struct nand_chip *chip)
41 {
42         return (uint8_t) cpu_to_le16(readw(chip->legacy.IO_ADDR_R));
43 }
44
45 /**
46  * nand_select_chip - [DEFAULT] control CE line
47  * @chip: NAND chip object
48  * @chipnr: chipnumber to select, -1 for deselect
49  *
50  * Default select function for 1 chip devices.
51  */
52 static void nand_select_chip(struct nand_chip *chip, int chipnr)
53 {
54         switch (chipnr) {
55         case -1:
56                 chip->legacy.cmd_ctrl(chip, NAND_CMD_NONE,
57                                       0 | NAND_CTRL_CHANGE);
58                 break;
59         case 0:
60                 break;
61
62         default:
63                 BUG();
64         }
65 }
66
67 /**
68  * nand_write_byte - [DEFAULT] write single byte to chip
69  * @chip: NAND chip object
70  * @byte: value to write
71  *
72  * Default function to write a byte to I/O[7:0]
73  */
74 static void nand_write_byte(struct nand_chip *chip, uint8_t byte)
75 {
76         chip->legacy.write_buf(chip, &byte, 1);
77 }
78
79 /**
80  * nand_write_byte16 - [DEFAULT] write single byte to a chip with width 16
81  * @chip: NAND chip object
82  * @byte: value to write
83  *
84  * Default function to write a byte to I/O[7:0] on a 16-bit wide chip.
85  */
86 static void nand_write_byte16(struct nand_chip *chip, uint8_t byte)
87 {
88         uint16_t word = byte;
89
90         /*
91          * It's not entirely clear what should happen to I/O[15:8] when writing
92          * a byte. The ONFi spec (Revision 3.1; 2012-09-19, Section 2.16) reads:
93          *
94          *    When the host supports a 16-bit bus width, only data is
95          *    transferred at the 16-bit width. All address and command line
96          *    transfers shall use only the lower 8-bits of the data bus. During
97          *    command transfers, the host may place any value on the upper
98          *    8-bits of the data bus. During address transfers, the host shall
99          *    set the upper 8-bits of the data bus to 00h.
100          *
101          * One user of the write_byte callback is nand_set_features. The
102          * four parameters are specified to be written to I/O[7:0], but this is
103          * neither an address nor a command transfer. Let's assume a 0 on the
104          * upper I/O lines is OK.
105          */
106         chip->legacy.write_buf(chip, (uint8_t *)&word, 2);
107 }
108
109 /**
110  * nand_write_buf - [DEFAULT] write buffer to chip
111  * @chip: NAND chip object
112  * @buf: data buffer
113  * @len: number of bytes to write
114  *
115  * Default write function for 8bit buswidth.
116  */
117 static void nand_write_buf(struct nand_chip *chip, const uint8_t *buf, int len)
118 {
119         iowrite8_rep(chip->legacy.IO_ADDR_W, buf, len);
120 }
121
122 /**
123  * nand_read_buf - [DEFAULT] read chip data into buffer
124  * @chip: NAND chip object
125  * @buf: buffer to store date
126  * @len: number of bytes to read
127  *
128  * Default read function for 8bit buswidth.
129  */
130 static void nand_read_buf(struct nand_chip *chip, uint8_t *buf, int len)
131 {
132         ioread8_rep(chip->legacy.IO_ADDR_R, buf, len);
133 }
134
135 /**
136  * nand_write_buf16 - [DEFAULT] write buffer to chip
137  * @chip: NAND chip object
138  * @buf: data buffer
139  * @len: number of bytes to write
140  *
141  * Default write function for 16bit buswidth.
142  */
143 static void nand_write_buf16(struct nand_chip *chip, const uint8_t *buf,
144                              int len)
145 {
146         u16 *p = (u16 *) buf;
147
148         iowrite16_rep(chip->legacy.IO_ADDR_W, p, len >> 1);
149 }
150
151 /**
152  * nand_read_buf16 - [DEFAULT] read chip data into buffer
153  * @chip: NAND chip object
154  * @buf: buffer to store date
155  * @len: number of bytes to read
156  *
157  * Default read function for 16bit buswidth.
158  */
159 static void nand_read_buf16(struct nand_chip *chip, uint8_t *buf, int len)
160 {
161         u16 *p = (u16 *) buf;
162
163         ioread16_rep(chip->legacy.IO_ADDR_R, p, len >> 1);
164 }
165
166 /**
167  * panic_nand_wait_ready - [GENERIC] Wait for the ready pin after commands.
168  * @chip: NAND chip object
169  * @timeo: Timeout
170  *
171  * Helper function for nand_wait_ready used when needing to wait in interrupt
172  * context.
173  */
174 static void panic_nand_wait_ready(struct nand_chip *chip, unsigned long timeo)
175 {
176         int i;
177
178         /* Wait for the device to get ready */
179         for (i = 0; i < timeo; i++) {
180                 if (chip->legacy.dev_ready(chip))
181                         break;
182                 touch_softlockup_watchdog();
183                 mdelay(1);
184         }
185 }
186
187 /**
188  * nand_wait_ready - [GENERIC] Wait for the ready pin after commands.
189  * @chip: NAND chip object
190  *
191  * Wait for the ready pin after a command, and warn if a timeout occurs.
192  */
193 void nand_wait_ready(struct nand_chip *chip)
194 {
195         unsigned long timeo = 400;
196
197         if (in_interrupt() || oops_in_progress)
198                 return panic_nand_wait_ready(chip, timeo);
199
200         /* Wait until command is processed or timeout occurs */
201         timeo = jiffies + msecs_to_jiffies(timeo);
202         do {
203                 if (chip->legacy.dev_ready(chip))
204                         return;
205                 cond_resched();
206         } while (time_before(jiffies, timeo));
207
208         if (!chip->legacy.dev_ready(chip))
209                 pr_warn_ratelimited("timeout while waiting for chip to become ready\n");
210 }
211 EXPORT_SYMBOL_GPL(nand_wait_ready);
212
213 /**
214  * nand_wait_status_ready - [GENERIC] Wait for the ready status after commands.
215  * @chip: NAND chip object
216  * @timeo: Timeout in ms
217  *
218  * Wait for status ready (i.e. command done) or timeout.
219  */
220 static void nand_wait_status_ready(struct nand_chip *chip, unsigned long timeo)
221 {
222         int ret;
223
224         timeo = jiffies + msecs_to_jiffies(timeo);
225         do {
226                 u8 status;
227
228                 ret = nand_read_data_op(chip, &status, sizeof(status), true);
229                 if (ret)
230                         return;
231
232                 if (status & NAND_STATUS_READY)
233                         break;
234                 touch_softlockup_watchdog();
235         } while (time_before(jiffies, timeo));
236 };
237
238 /**
239  * nand_command - [DEFAULT] Send command to NAND device
240  * @chip: NAND chip object
241  * @command: the command to be sent
242  * @column: the column address for this command, -1 if none
243  * @page_addr: the page address for this command, -1 if none
244  *
245  * Send command to NAND device. This function is used for small page devices
246  * (512 Bytes per page).
247  */
248 static void nand_command(struct nand_chip *chip, unsigned int command,
249                          int column, int page_addr)
250 {
251         struct mtd_info *mtd = nand_to_mtd(chip);
252         int ctrl = NAND_CTRL_CLE | NAND_CTRL_CHANGE;
253
254         /* Write out the command to the device */
255         if (command == NAND_CMD_SEQIN) {
256                 int readcmd;
257
258                 if (column >= mtd->writesize) {
259                         /* OOB area */
260                         column -= mtd->writesize;
261                         readcmd = NAND_CMD_READOOB;
262                 } else if (column < 256) {
263                         /* First 256 bytes --> READ0 */
264                         readcmd = NAND_CMD_READ0;
265                 } else {
266                         column -= 256;
267                         readcmd = NAND_CMD_READ1;
268                 }
269                 chip->legacy.cmd_ctrl(chip, readcmd, ctrl);
270                 ctrl &= ~NAND_CTRL_CHANGE;
271         }
272         if (command != NAND_CMD_NONE)
273                 chip->legacy.cmd_ctrl(chip, command, ctrl);
274
275         /* Address cycle, when necessary */
276         ctrl = NAND_CTRL_ALE | NAND_CTRL_CHANGE;
277         /* Serially input address */
278         if (column != -1) {
279                 /* Adjust columns for 16 bit buswidth */
280                 if (chip->options & NAND_BUSWIDTH_16 &&
281                                 !nand_opcode_8bits(command))
282                         column >>= 1;
283                 chip->legacy.cmd_ctrl(chip, column, ctrl);
284                 ctrl &= ~NAND_CTRL_CHANGE;
285         }
286         if (page_addr != -1) {
287                 chip->legacy.cmd_ctrl(chip, page_addr, ctrl);
288                 ctrl &= ~NAND_CTRL_CHANGE;
289                 chip->legacy.cmd_ctrl(chip, page_addr >> 8, ctrl);
290                 if (chip->options & NAND_ROW_ADDR_3)
291                         chip->legacy.cmd_ctrl(chip, page_addr >> 16, ctrl);
292         }
293         chip->legacy.cmd_ctrl(chip, NAND_CMD_NONE,
294                               NAND_NCE | NAND_CTRL_CHANGE);
295
296         /*
297          * Program and erase have their own busy handlers status and sequential
298          * in needs no delay
299          */
300         switch (command) {
301
302         case NAND_CMD_NONE:
303         case NAND_CMD_PAGEPROG:
304         case NAND_CMD_ERASE1:
305         case NAND_CMD_ERASE2:
306         case NAND_CMD_SEQIN:
307         case NAND_CMD_STATUS:
308         case NAND_CMD_READID:
309         case NAND_CMD_SET_FEATURES:
310                 return;
311
312         case NAND_CMD_RESET:
313                 if (chip->legacy.dev_ready)
314                         break;
315                 udelay(chip->legacy.chip_delay);
316                 chip->legacy.cmd_ctrl(chip, NAND_CMD_STATUS,
317                                       NAND_CTRL_CLE | NAND_CTRL_CHANGE);
318                 chip->legacy.cmd_ctrl(chip, NAND_CMD_NONE,
319                                       NAND_NCE | NAND_CTRL_CHANGE);
320                 /* EZ-NAND can take upto 250ms as per ONFi v4.0 */
321                 nand_wait_status_ready(chip, 250);
322                 return;
323
324                 /* This applies to read commands */
325         case NAND_CMD_READ0:
326                 /*
327                  * READ0 is sometimes used to exit GET STATUS mode. When this
328                  * is the case no address cycles are requested, and we can use
329                  * this information to detect that we should not wait for the
330                  * device to be ready.
331                  */
332                 if (column == -1 && page_addr == -1)
333                         return;
334                 /* fall through */
335
336         default:
337                 /*
338                  * If we don't have access to the busy pin, we apply the given
339                  * command delay
340                  */
341                 if (!chip->legacy.dev_ready) {
342                         udelay(chip->legacy.chip_delay);
343                         return;
344                 }
345         }
346         /*
347          * Apply this short delay always to ensure that we do wait tWB in
348          * any case on any machine.
349          */
350         ndelay(100);
351
352         nand_wait_ready(chip);
353 }
354
355 static void nand_ccs_delay(struct nand_chip *chip)
356 {
357         /*
358          * The controller already takes care of waiting for tCCS when the RNDIN
359          * or RNDOUT command is sent, return directly.
360          */
361         if (!(chip->options & NAND_WAIT_TCCS))
362                 return;
363
364         /*
365          * Wait tCCS_min if it is correctly defined, otherwise wait 500ns
366          * (which should be safe for all NANDs).
367          */
368         if (nand_has_setup_data_iface(chip))
369                 ndelay(chip->data_interface.timings.sdr.tCCS_min / 1000);
370         else
371                 ndelay(500);
372 }
373
374 /**
375  * nand_command_lp - [DEFAULT] Send command to NAND large page device
376  * @chip: NAND chip object
377  * @command: the command to be sent
378  * @column: the column address for this command, -1 if none
379  * @page_addr: the page address for this command, -1 if none
380  *
381  * Send command to NAND device. This is the version for the new large page
382  * devices. We don't have the separate regions as we have in the small page
383  * devices. We must emulate NAND_CMD_READOOB to keep the code compatible.
384  */
385 static void nand_command_lp(struct nand_chip *chip, unsigned int command,
386                             int column, int page_addr)
387 {
388         struct mtd_info *mtd = nand_to_mtd(chip);
389
390         /* Emulate NAND_CMD_READOOB */
391         if (command == NAND_CMD_READOOB) {
392                 column += mtd->writesize;
393                 command = NAND_CMD_READ0;
394         }
395
396         /* Command latch cycle */
397         if (command != NAND_CMD_NONE)
398                 chip->legacy.cmd_ctrl(chip, command,
399                                       NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
400
401         if (column != -1 || page_addr != -1) {
402                 int ctrl = NAND_CTRL_CHANGE | NAND_NCE | NAND_ALE;
403
404                 /* Serially input address */
405                 if (column != -1) {
406                         /* Adjust columns for 16 bit buswidth */
407                         if (chip->options & NAND_BUSWIDTH_16 &&
408                                         !nand_opcode_8bits(command))
409                                 column >>= 1;
410                         chip->legacy.cmd_ctrl(chip, column, ctrl);
411                         ctrl &= ~NAND_CTRL_CHANGE;
412
413                         /* Only output a single addr cycle for 8bits opcodes. */
414                         if (!nand_opcode_8bits(command))
415                                 chip->legacy.cmd_ctrl(chip, column >> 8, ctrl);
416                 }
417                 if (page_addr != -1) {
418                         chip->legacy.cmd_ctrl(chip, page_addr, ctrl);
419                         chip->legacy.cmd_ctrl(chip, page_addr >> 8,
420                                              NAND_NCE | NAND_ALE);
421                         if (chip->options & NAND_ROW_ADDR_3)
422                                 chip->legacy.cmd_ctrl(chip, page_addr >> 16,
423                                                       NAND_NCE | NAND_ALE);
424                 }
425         }
426         chip->legacy.cmd_ctrl(chip, NAND_CMD_NONE,
427                               NAND_NCE | NAND_CTRL_CHANGE);
428
429         /*
430          * Program and erase have their own busy handlers status, sequential
431          * in and status need no delay.
432          */
433         switch (command) {
434
435         case NAND_CMD_NONE:
436         case NAND_CMD_CACHEDPROG:
437         case NAND_CMD_PAGEPROG:
438         case NAND_CMD_ERASE1:
439         case NAND_CMD_ERASE2:
440         case NAND_CMD_SEQIN:
441         case NAND_CMD_STATUS:
442         case NAND_CMD_READID:
443         case NAND_CMD_SET_FEATURES:
444                 return;
445
446         case NAND_CMD_RNDIN:
447                 nand_ccs_delay(chip);
448                 return;
449
450         case NAND_CMD_RESET:
451                 if (chip->legacy.dev_ready)
452                         break;
453                 udelay(chip->legacy.chip_delay);
454                 chip->legacy.cmd_ctrl(chip, NAND_CMD_STATUS,
455                                       NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
456                 chip->legacy.cmd_ctrl(chip, NAND_CMD_NONE,
457                                       NAND_NCE | NAND_CTRL_CHANGE);
458                 /* EZ-NAND can take upto 250ms as per ONFi v4.0 */
459                 nand_wait_status_ready(chip, 250);
460                 return;
461
462         case NAND_CMD_RNDOUT:
463                 /* No ready / busy check necessary */
464                 chip->legacy.cmd_ctrl(chip, NAND_CMD_RNDOUTSTART,
465                                       NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
466                 chip->legacy.cmd_ctrl(chip, NAND_CMD_NONE,
467                                       NAND_NCE | NAND_CTRL_CHANGE);
468
469                 nand_ccs_delay(chip);
470                 return;
471
472         case NAND_CMD_READ0:
473                 /*
474                  * READ0 is sometimes used to exit GET STATUS mode. When this
475                  * is the case no address cycles are requested, and we can use
476                  * this information to detect that READSTART should not be
477                  * issued.
478                  */
479                 if (column == -1 && page_addr == -1)
480                         return;
481
482                 chip->legacy.cmd_ctrl(chip, NAND_CMD_READSTART,
483                                       NAND_NCE | NAND_CLE | NAND_CTRL_CHANGE);
484                 chip->legacy.cmd_ctrl(chip, NAND_CMD_NONE,
485                                       NAND_NCE | NAND_CTRL_CHANGE);
486
487                 /* fall through - This applies to read commands */
488         default:
489                 /*
490                  * If we don't have access to the busy pin, we apply the given
491                  * command delay.
492                  */
493                 if (!chip->legacy.dev_ready) {
494                         udelay(chip->legacy.chip_delay);
495                         return;
496                 }
497         }
498
499         /*
500          * Apply this short delay always to ensure that we do wait tWB in
501          * any case on any machine.
502          */
503         ndelay(100);
504
505         nand_wait_ready(chip);
506 }
507
508 /**
509  * nand_get_set_features_notsupp - set/get features stub returning -ENOTSUPP
510  * @chip: nand chip info structure
511  * @addr: feature address.
512  * @subfeature_param: the subfeature parameters, a four bytes array.
513  *
514  * Should be used by NAND controller drivers that do not support the SET/GET
515  * FEATURES operations.
516  */
517 int nand_get_set_features_notsupp(struct nand_chip *chip, int addr,
518                                   u8 *subfeature_param)
519 {
520         return -ENOTSUPP;
521 }
522 EXPORT_SYMBOL(nand_get_set_features_notsupp);
523
524 /**
525  * nand_wait - [DEFAULT] wait until the command is done
526  * @chip: NAND chip structure
527  *
528  * Wait for command done. This applies to erase and program only.
529  */
530 static int nand_wait(struct nand_chip *chip)
531 {
532
533         unsigned long timeo = 400;
534         u8 status;
535         int ret;
536
537         /*
538          * Apply this short delay always to ensure that we do wait tWB in any
539          * case on any machine.
540          */
541         ndelay(100);
542
543         ret = nand_status_op(chip, NULL);
544         if (ret)
545                 return ret;
546
547         if (in_interrupt() || oops_in_progress)
548                 panic_nand_wait(chip, timeo);
549         else {
550                 timeo = jiffies + msecs_to_jiffies(timeo);
551                 do {
552                         if (chip->legacy.dev_ready) {
553                                 if (chip->legacy.dev_ready(chip))
554                                         break;
555                         } else {
556                                 ret = nand_read_data_op(chip, &status,
557                                                         sizeof(status), true);
558                                 if (ret)
559                                         return ret;
560
561                                 if (status & NAND_STATUS_READY)
562                                         break;
563                         }
564                         cond_resched();
565                 } while (time_before(jiffies, timeo));
566         }
567
568         ret = nand_read_data_op(chip, &status, sizeof(status), true);
569         if (ret)
570                 return ret;
571
572         /* This can happen if in case of timeout or buggy dev_ready */
573         WARN_ON(!(status & NAND_STATUS_READY));
574         return status;
575 }
576
577 void nand_legacy_set_defaults(struct nand_chip *chip)
578 {
579         unsigned int busw = chip->options & NAND_BUSWIDTH_16;
580
581         if (nand_has_exec_op(chip))
582                 return;
583
584         /* check for proper chip_delay setup, set 20us if not */
585         if (!chip->legacy.chip_delay)
586                 chip->legacy.chip_delay = 20;
587
588         /* check, if a user supplied command function given */
589         if (!chip->legacy.cmdfunc)
590                 chip->legacy.cmdfunc = nand_command;
591
592         /* check, if a user supplied wait function given */
593         if (chip->legacy.waitfunc == NULL)
594                 chip->legacy.waitfunc = nand_wait;
595
596         if (!chip->legacy.select_chip)
597                 chip->legacy.select_chip = nand_select_chip;
598
599         /* If called twice, pointers that depend on busw may need to be reset */
600         if (!chip->legacy.read_byte || chip->legacy.read_byte == nand_read_byte)
601                 chip->legacy.read_byte = busw ? nand_read_byte16 : nand_read_byte;
602         if (!chip->legacy.write_buf || chip->legacy.write_buf == nand_write_buf)
603                 chip->legacy.write_buf = busw ? nand_write_buf16 : nand_write_buf;
604         if (!chip->legacy.write_byte || chip->legacy.write_byte == nand_write_byte)
605                 chip->legacy.write_byte = busw ? nand_write_byte16 : nand_write_byte;
606         if (!chip->legacy.read_buf || chip->legacy.read_buf == nand_read_buf)
607                 chip->legacy.read_buf = busw ? nand_read_buf16 : nand_read_buf;
608 }
609
610 void nand_legacy_adjust_cmdfunc(struct nand_chip *chip)
611 {
612         struct mtd_info *mtd = nand_to_mtd(chip);
613
614         /* Do not replace user supplied command function! */
615         if (mtd->writesize > 512 && chip->legacy.cmdfunc == nand_command)
616                 chip->legacy.cmdfunc = nand_command_lp;
617 }
618
619 int nand_legacy_check_hooks(struct nand_chip *chip)
620 {
621         /*
622          * ->legacy.cmdfunc() is legacy and will only be used if ->exec_op() is
623          * not populated.
624          */
625         if (nand_has_exec_op(chip))
626                 return 0;
627
628         /*
629          * Default functions assigned for ->legacy.cmdfunc() and
630          * ->legacy.select_chip() both expect ->legacy.cmd_ctrl() to be
631          *  populated.
632          */
633         if ((!chip->legacy.cmdfunc || !chip->legacy.select_chip) &&
634             !chip->legacy.cmd_ctrl) {
635                 pr_err("->legacy.cmd_ctrl() should be provided\n");
636                 return -EINVAL;
637         }
638
639         return 0;
640 }