at91samd: Bail early if trying to erase protected sector
[fw/openocd] / src / flash / nor / at91samd.c
1 /***************************************************************************
2  *   Copyright (C) 2013 by Andrey Yurovsky                                 *
3  *   Andrey Yurovsky <yurovsky@gmail.com>                                  *
4  *                                                                         *
5  *   This program is free software; you can redistribute it and/or modify  *
6  *   it under the terms of the GNU General Public License as published by  *
7  *   the Free Software Foundation; either version 2 of the License, or     *
8  *   (at your option) any later version.                                   *
9  *                                                                         *
10  *   This program is distributed in the hope that it will be useful,       *
11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
13  *   GNU General Public License for more details.                          *
14  *                                                                         *
15  *   You should have received a copy of the GNU General Public License     *
16  *   along with this program; if not, write to the                         *
17  *   Free Software Foundation, Inc.,                                       *
18  *   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.           *
19  ***************************************************************************/
20
21 #ifdef HAVE_CONFIG_H
22 #include "config.h"
23 #endif
24
25 #include "imp.h"
26
27 #define SAMD_NUM_SECTORS        16
28
29 #define SAMD_FLASH                      0x00000000      /* physical Flash memory */
30 #define SAMD_DSU                        0x41002000      /* Device Service Unit */
31 #define SAMD_NVMCTRL            0x41004000      /* Non-volatile memory controller */
32
33 #define SAMD_DSU_DID            0x18            /* Device ID register */
34
35 #define SAMD_NVMCTRL_CTRLA              0x00    /* NVM control A register */
36 #define SAMD_NVMCTRL_CTRLB              0x04    /* NVM control B register */
37 #define SAMD_NVMCTRL_PARAM              0x08    /* NVM parameters register */
38 #define SAMD_NVMCTRL_INTFLAG    0x18    /* NVM Interupt Flag Status & Clear */
39 #define SAMD_NVMCTRL_STATUS             0x18    /* NVM status register */
40 #define SAMD_NVMCTRL_ADDR               0x1C    /* NVM address register */
41 #define SAMD_NVMCTRL_LOCK               0x20    /* NVM Lock section register */
42
43 #define SAMD_CMDEX_KEY          0xA5UL
44 #define SAMD_NVM_CMD(n)         ((SAMD_CMDEX_KEY << 8) | (n & 0x7F))
45
46 /* NVMCTRL commands.  See Table 20-4 in 42129F–SAM–10/2013 */
47 #define SAMD_NVM_CMD_ER         0x02            /* Erase Row */
48 #define SAMD_NVM_CMD_WP         0x04            /* Write Page */
49 #define SAMD_NVM_CMD_EAR        0x05            /* Erase Auxilary Row */
50 #define SAMD_NVM_CMD_WAP        0x06            /* Write Auxilary Page */
51 #define SAMD_NVM_CMD_LR         0x40            /* Lock Region */
52 #define SAMD_NVM_CMD_UR         0x41            /* Unlock Region */
53 #define SAMD_NVM_CMD_SPRM       0x42            /* Set Power Reduction Mode */
54 #define SAMD_NVM_CMD_CPRM       0x43            /* Clear Power Reduction Mode */
55 #define SAMD_NVM_CMD_PBC        0x44            /* Page Buffer Clear */
56 #define SAMD_NVM_CMD_SSB        0x45            /* Set Security Bit */
57 #define SAMD_NVM_CMD_INVALL     0x46            /* Invalidate all caches */
58
59 /* Known identifiers */
60 #define SAMD_PROCESSOR_M0       0x01
61 #define SAMD_FAMILY_D           0x00
62 #define SAMD_SERIES_20          0x00
63 #define SAMD_SERIES_21          0x01
64
65 struct samd_part {
66         uint8_t id;
67         const char *name;
68         uint32_t flash_kb;
69         uint32_t ram_kb;
70 };
71
72 /* Known SAMD20 parts. See Table 12-8 in 42129F–SAM–10/2013 */
73 static const struct samd_part samd20_parts[] = {
74         { 0x0, "SAMD20J18A", 256, 32 },
75         { 0x1, "SAMD20J17A", 128, 16 },
76         { 0x2, "SAMD20J16A", 64, 8 },
77         { 0x3, "SAMD20J15A", 32, 4 },
78         { 0x4, "SAMD20J14A", 16, 2 },
79         { 0x5, "SAMD20G18A", 256, 32 },
80         { 0x6, "SAMD20G17A", 128, 16 },
81         { 0x7, "SAMD20G16A", 64, 8 },
82         { 0x8, "SAMD20G15A", 32, 4 },
83         { 0x9, "SAMD20G14A", 16, 2 },
84         { 0xB, "SAMD20E17A", 128, 16 },
85         { 0xC, "SAMD20E16A", 64, 8 },
86         { 0xD, "SAMD20E15A", 32, 4 },
87         { 0xE, "SAMD20E14A", 16, 2 },
88 };
89
90 /* Known SAMD21 parts. */
91 static const struct samd_part samd21_parts[] = {
92         { 0x0, "SAMD21J18A", 256, 32 },
93         { 0x1, "SAMD21J17A", 128, 16 },
94         { 0x2, "SAMD21J16A", 64, 8 },
95         { 0x3, "SAMD21J15A", 32, 4 },
96         { 0x4, "SAMD21J14A", 16, 2 },
97         { 0x5, "SAMD21G18A", 256, 32 },
98         { 0x6, "SAMD21G17A", 128, 16 },
99         { 0x7, "SAMD21G16A", 64, 8 },
100         { 0x8, "SAMD21G15A", 32, 4 },
101         { 0x9, "SAMD21G14A", 16, 2 },
102         { 0xA, "SAMD21E18A", 256, 32 },
103         { 0xB, "SAMD21E17A", 128, 16 },
104         { 0xC, "SAMD21E16A", 64, 8 },
105         { 0xD, "SAMD21E15A", 32, 4 },
106         { 0xE, "SAMD21E14A", 16, 2 },
107 };
108
109 /* Each family of parts contains a parts table in the DEVSEL field of DID.  The
110  * processor ID, family ID, and series ID are used to determine which exact
111  * family this is and then we can use the corresponding table. */
112 struct samd_family {
113         uint8_t processor;
114         uint8_t family;
115         uint8_t series;
116         const struct samd_part *parts;
117         size_t num_parts;
118 };
119
120 /* Known SAMD families */
121 static const struct samd_family samd_families[] = {
122         { SAMD_PROCESSOR_M0, SAMD_FAMILY_D, SAMD_SERIES_20,
123                 samd20_parts, ARRAY_SIZE(samd20_parts) },
124         { SAMD_PROCESSOR_M0, SAMD_FAMILY_D, SAMD_SERIES_21,
125                 samd21_parts, ARRAY_SIZE(samd21_parts) },
126 };
127
128 struct samd_info {
129         uint32_t page_size;
130         int num_pages;
131         int sector_size;
132
133         bool probed;
134         struct target *target;
135         struct samd_info *next;
136 };
137
138 static struct samd_info *samd_chips;
139
140 static const struct samd_part *samd_find_part(uint32_t id)
141 {
142         uint8_t processor = (id >> 28);
143         uint8_t family = (id >> 24) & 0x0F;
144         uint8_t series = (id >> 16) & 0xFF;
145         uint8_t devsel = id & 0xFF;
146
147         for (unsigned i = 0; i < ARRAY_SIZE(samd_families); i++) {
148                 if (samd_families[i].processor == processor &&
149                         samd_families[i].series == series &&
150                         samd_families[i].family == family) {
151                         for (unsigned j = 0; j < samd_families[i].num_parts; j++) {
152                                 if (samd_families[i].parts[j].id == devsel)
153                                         return &samd_families[i].parts[j];
154                         }
155                 }
156         }
157
158         return NULL;
159 }
160
161 static int samd_protect_check(struct flash_bank *bank)
162 {
163         int res;
164         uint16_t lock;
165
166         res = target_read_u16(bank->target,
167                         SAMD_NVMCTRL + SAMD_NVMCTRL_LOCK, &lock);
168         if (res != ERROR_OK)
169                 return res;
170
171         /* Lock bits are active-low */
172         for (int i = 0; i < bank->num_sectors; i++)
173                 bank->sectors[i].is_protected = !(lock & (1<<i));
174
175         return ERROR_OK;
176 }
177
178 static int samd_probe(struct flash_bank *bank)
179 {
180         uint32_t id, param;
181         int res;
182         struct samd_info *chip = (struct samd_info *)bank->driver_priv;
183         const struct samd_part *part;
184
185         if (chip->probed)
186                 return ERROR_OK;
187
188         res = target_read_u32(bank->target, SAMD_DSU + SAMD_DSU_DID, &id);
189         if (res != ERROR_OK) {
190                 LOG_ERROR("Couldn't read Device ID register");
191                 return res;
192         }
193
194         part = samd_find_part(id);
195         if (part == NULL) {
196                 LOG_ERROR("Couldn't find part correspoding to DID %08" PRIx32, id);
197                 return ERROR_FAIL;
198         }
199
200         res = target_read_u32(bank->target,
201                         SAMD_NVMCTRL + SAMD_NVMCTRL_PARAM, &param);
202         if (res != ERROR_OK) {
203                 LOG_ERROR("Couldn't read NVM Parameters register");
204                 return res;
205         }
206
207         bank->size = part->flash_kb * 1024;
208
209         chip->sector_size = bank->size / SAMD_NUM_SECTORS;
210
211         /* The PSZ field (bits 18:16) indicate the page size bytes as 2^(3+n) so
212          * 0 is 8KB and 7 is 1024KB. */
213         chip->page_size = (8 << ((param >> 16) & 0x7));
214         /* The NVMP field (bits 15:0) indicates the total number of pages */
215         chip->num_pages = param & 0xFFFF;
216
217         /* Sanity check: the total flash size in the DSU should match the page size
218          * multiplied by the number of pages. */
219         if (bank->size != chip->num_pages * chip->page_size) {
220                 LOG_WARNING("SAMD: bank size doesn't match NVM parameters. "
221                                 "Identified %uKB Flash but NVMCTRL reports %u %uB pages",
222                                 part->flash_kb, chip->num_pages, chip->page_size);
223         }
224
225         /* Allocate the sector table */
226         bank->num_sectors = SAMD_NUM_SECTORS;
227         bank->sectors = calloc(bank->num_sectors, sizeof((bank->sectors)[0]));
228         if (!bank->sectors)
229                 return ERROR_FAIL;
230
231         /* Fill out the sector information: all SAMD sectors are the same size and
232          * there is always a fixed number of them. */
233         for (int i = 0; i < bank->num_sectors; i++) {
234                 bank->sectors[i].size = chip->sector_size;
235                 bank->sectors[i].offset = i * chip->sector_size;
236                 /* mark as unknown */
237                 bank->sectors[i].is_erased = -1;
238                 bank->sectors[i].is_protected = -1;
239         }
240
241         samd_protect_check(bank);
242
243         /* Done */
244         chip->probed = true;
245
246         LOG_INFO("SAMD MCU: %s (%uKB Flash, %uKB RAM)", part->name,
247                         part->flash_kb, part->ram_kb);
248
249         return ERROR_OK;
250 }
251
252 static int samd_protect(struct flash_bank *bank, int set, int first, int last)
253 {
254         int res;
255         struct samd_info *chip = (struct samd_info *)bank->driver_priv;
256
257         for (int s = first; s <= last; s++) {
258                 /* Load an address that is within this sector (we use offset 0) */
259                 res = target_write_u32(bank->target, SAMD_NVMCTRL + SAMD_NVMCTRL_ADDR,
260                                 s * chip->sector_size);
261                 if (res != ERROR_OK)
262                         return res;
263
264                 /* Tell the controller to lock that sector */
265                 res = target_write_u16(bank->target,
266                                 SAMD_NVMCTRL + SAMD_NVMCTRL_CTRLA,
267                                 SAMD_NVM_CMD(SAMD_NVM_CMD_LR));
268                 if (res != ERROR_OK)
269                         return res;
270         }
271
272         samd_protect_check(bank);
273
274         return ERROR_OK;
275 }
276
277 static bool samd_check_error(struct flash_bank *bank)
278 {
279         int ret;
280         bool error;
281         uint16_t status;
282
283         ret = target_read_u16(bank->target,
284                         SAMD_NVMCTRL + SAMD_NVMCTRL_STATUS, &status);
285         if (ret != ERROR_OK) {
286                 LOG_ERROR("Can't read NVM status");
287                 return true;
288         }
289
290         if (status & 0x001C) {
291                 if (status & (1 << 4)) /* NVME */
292                         LOG_ERROR("SAMD: NVM Error");
293                 if (status & (1 << 3)) /* LOCKE */
294                         LOG_ERROR("SAMD: NVM lock error");
295                 if (status & (1 << 2)) /* PROGE */
296                         LOG_ERROR("SAMD: NVM programming error");
297
298                 error = true;
299         } else {
300                 error = false;
301         }
302
303         /* Clear the error conditions by writing a one to them */
304         ret = target_write_u16(bank->target,
305                         SAMD_NVMCTRL + SAMD_NVMCTRL_STATUS, status);
306         if (ret != ERROR_OK)
307                 LOG_ERROR("Can't clear NVM error conditions");
308
309         return error;
310 }
311
312 static int samd_erase_row(struct flash_bank *bank, uint32_t address)
313 {
314         int res;
315         bool error = false;
316
317         /* Set an address contained in the row to be erased */
318         res = target_write_u32(bank->target,
319                         SAMD_NVMCTRL + SAMD_NVMCTRL_ADDR, address >> 1);
320         if (res == ERROR_OK) {
321                 /* Issue the Erase Row command to erase that row */
322                 res = target_write_u16(bank->target,
323                                 SAMD_NVMCTRL + SAMD_NVMCTRL_CTRLA,
324                                 SAMD_NVM_CMD(SAMD_NVM_CMD_ER));
325
326                 /* Check (and clear) error conditions */
327                 error = samd_check_error(bank);
328         }
329
330         if (res != ERROR_OK || error)  {
331                 LOG_ERROR("Failed to erase row containing %08X" PRIx32, address);
332                 return ERROR_FAIL;
333         }
334
335         return ERROR_OK;
336 }
337
338 static int samd_erase(struct flash_bank *bank, int first, int last)
339 {
340         int res;
341         int rows_in_sector;
342         struct samd_info *chip = (struct samd_info *)bank->driver_priv;
343
344         if (bank->target->state != TARGET_HALTED) {
345                 LOG_ERROR("Target not halted");
346
347                 return ERROR_TARGET_NOT_HALTED;
348         }
349
350         if (!chip->probed) {
351                 if (samd_probe(bank) != ERROR_OK)
352                         return ERROR_FLASH_BANK_NOT_PROBED;
353         }
354
355         /* The SAMD NVM has row erase granularity.  There are four pages in a row
356          * and the number of rows in a sector depends on the sector size, which in
357          * turn depends on the Flash capacity as there is a fixed number of
358          * sectors. */
359         rows_in_sector = chip->sector_size / (chip->page_size * 4);
360
361         /* For each sector to be erased */
362         for (int s = first; s <= last; s++) {
363                 if (bank->sectors[s].is_protected) {
364                         LOG_ERROR("SAMD: failed to erase sector %d. That sector is write-protected", s);
365                         return ERROR_FLASH_OPERATION_FAILED;
366                 }
367
368                 if (!bank->sectors[s].is_erased) {
369                         /* For each row in that sector */
370                         for (int r = s * rows_in_sector; r < (s + 1) * rows_in_sector; r++) {
371                                 res = samd_erase_row(bank, r * chip->page_size * 4);
372                                 if (res != ERROR_OK) {
373                                         LOG_ERROR("SAMD: failed to erase sector %d", s);
374                                         return res;
375                                 }
376                         }
377
378                         bank->sectors[s].is_erased = 1;
379                 }
380         }
381
382         return ERROR_OK;
383 }
384
385 static struct flash_sector *samd_find_sector_by_address(struct flash_bank *bank, uint32_t address)
386 {
387         struct samd_info *chip = (struct samd_info *)bank->driver_priv;
388
389         for (int i = 0; i < bank->num_sectors; i++) {
390                 if (bank->sectors[i].offset <= address &&
391                     address < bank->sectors[i].offset + chip->sector_size)
392                         return &bank->sectors[i];
393         }
394         return NULL;
395 }
396
397 /* Write an entire row (four pages) from host buffer 'buf' to row-aligned
398  * 'address' in the Flash. */
399 static int samd_write_row(struct flash_bank *bank, uint32_t address,
400                 const uint8_t *buf)
401 {
402         int res;
403         struct samd_info *chip = (struct samd_info *)bank->driver_priv;
404
405         struct flash_sector *sector = samd_find_sector_by_address(bank, address);
406
407         if (!sector) {
408                 LOG_ERROR("Can't find sector corresponding to address 0x%08" PRIx32, address);
409                 return ERROR_FLASH_OPERATION_FAILED;
410         }
411
412         if (sector->is_protected) {
413                 LOG_ERROR("Trying to write to a protected sector at 0x%08" PRIx32, address);
414                 return ERROR_FLASH_OPERATION_FAILED;
415         }
416
417         /* Erase the row that we'll be writing to */
418         res = samd_erase_row(bank, address);
419         if (res != ERROR_OK)
420                 return res;
421
422         /* Now write the pages in this row. */
423         for (unsigned int i = 0; i < 4; i++) {
424                 bool error;
425
426                 /* Write the page contents to the target's page buffer.  A page write
427                  * is issued automatically once the last location is written in the
428                  * page buffer (ie: a complete page has been written out). */
429                 res = target_write_memory(bank->target, address, 4,
430                                 chip->page_size / 4, buf);
431                 if (res != ERROR_OK) {
432                         LOG_ERROR("%s: %d", __func__, __LINE__);
433                         return res;
434                 }
435
436                 error = samd_check_error(bank);
437                 if (error)
438                         return ERROR_FAIL;
439
440                 /* Next page */
441                 address += chip->page_size;
442                 buf += chip->page_size;
443         }
444
445         sector->is_erased = 0;
446
447         return res;
448 }
449
450 /* Write partial contents into row-aligned 'address' on the Flash from host
451  * buffer 'buf' by writing 'nb' of 'buf' at 'row_offset' into the Flash row. */
452 static int samd_write_row_partial(struct flash_bank *bank, uint32_t address,
453                 const uint8_t *buf, uint32_t row_offset, uint32_t nb)
454 {
455         int res;
456         struct samd_info *chip = (struct samd_info *)bank->driver_priv;
457         uint32_t row_size = chip->page_size * 4;
458         uint8_t *rb = malloc(row_size);
459         if (!rb)
460                 return ERROR_FAIL;
461
462         assert(row_offset + nb < row_size);
463         assert((address % row_size) == 0);
464
465         /* Retrieve the full row contents from Flash */
466         res = target_read_memory(bank->target, address, 4, row_size / 4, rb);
467         if (res != ERROR_OK) {
468                 free(rb);
469                 return res;
470         }
471
472         /* Insert our partial row over the data from Flash */
473         memcpy(rb + (row_offset % row_size), buf, nb);
474
475         /* Write the row back out */
476         res = samd_write_row(bank, address, rb);
477         free(rb);
478
479         return res;
480 }
481
482 static int samd_write(struct flash_bank *bank, const uint8_t *buffer,
483                 uint32_t offset, uint32_t count)
484 {
485         int res;
486         uint32_t address;
487         uint32_t nb = 0;
488         struct samd_info *chip = (struct samd_info *)bank->driver_priv;
489         uint32_t row_size = chip->page_size * 4;
490
491         if (bank->target->state != TARGET_HALTED) {
492                 LOG_ERROR("Target not halted");
493
494                 return ERROR_TARGET_NOT_HALTED;
495         }
496
497         if (!chip->probed) {
498                 if (samd_probe(bank) != ERROR_OK)
499                         return ERROR_FLASH_BANK_NOT_PROBED;
500         }
501
502         if (offset % row_size) {
503                 /* We're starting at an unaligned offset so we'll write a partial row
504                  * comprising that offset and up to the end of that row. */
505                 nb = row_size - (offset % row_size);
506                 if (nb > count)
507                         nb = count;
508         } else if (count < row_size) {
509                 /* We're writing an aligned but partial row. */
510                 nb = count;
511         }
512
513         address = (offset / row_size) * row_size + bank->base;
514
515         if (nb > 0) {
516                 res = samd_write_row_partial(bank, address, buffer,
517                                 offset % row_size, nb);
518                 if (res != ERROR_OK)
519                         return res;
520
521                 /* We're done with the row contents */
522                 count -= nb;
523                 offset += nb;
524                 buffer += row_size;
525         }
526
527         /* There's at least one aligned row to write out. */
528         if (count >= row_size) {
529                 int nr = count / row_size + ((count % row_size) ? 1 : 0);
530                 unsigned int r = 0;
531
532                 for (unsigned int i = address / row_size;
533                                 (i < (address / row_size) + nr) && count > 0; i++) {
534                         address = (i * row_size) + bank->base;
535
536                         if (count >= row_size) {
537                                 res = samd_write_row(bank, address, buffer + (r * row_size));
538                                 /* Advance one row */
539                                 offset += row_size;
540                                 count -= row_size;
541                         } else {
542                                 res = samd_write_row_partial(bank, address,
543                                                 buffer + (r * row_size), 0, count);
544                                 /* We're done after this. */
545                                 offset += count;
546                                 count = 0;
547                         }
548
549                         r++;
550
551                         if (res != ERROR_OK)
552                                 return res;
553                 }
554         }
555
556         return ERROR_OK;
557 }
558
559 FLASH_BANK_COMMAND_HANDLER(samd_flash_bank_command)
560 {
561         struct samd_info *chip = samd_chips;
562
563         while (chip) {
564                 if (chip->target == bank->target)
565                         break;
566                 chip = chip->next;
567         }
568
569         if (!chip) {
570                 /* Create a new chip */
571                 chip = calloc(1, sizeof(*chip));
572                 if (!chip)
573                         return ERROR_FAIL;
574
575                 chip->target = bank->target;
576                 chip->probed = false;
577
578                 bank->driver_priv = chip;
579
580                 /* Insert it into the chips list (at head) */
581                 chip->next = samd_chips;
582                 samd_chips = chip;
583         }
584
585         if (bank->base != SAMD_FLASH) {
586                 LOG_ERROR("Address 0x%08" PRIx32 " invalid bank address (try 0x%08" PRIx32
587                                 "[at91samd series] )",
588                                 bank->base, SAMD_FLASH);
589                 return ERROR_FAIL;
590         }
591
592         return ERROR_OK;
593 }
594
595 COMMAND_HANDLER(samd_handle_info_command)
596 {
597         return ERROR_OK;
598 }
599
600 static const struct command_registration at91samd_exec_command_handlers[] = {
601         {
602                 .name = "info",
603                 .handler = samd_handle_info_command,
604                 .mode = COMMAND_EXEC,
605                 .help = "Print information about the current at91samd chip"
606                         "and its flash configuration.",
607         },
608         COMMAND_REGISTRATION_DONE
609 };
610
611 static const struct command_registration at91samd_command_handlers[] = {
612         {
613                 .name = "at91samd",
614                 .mode = COMMAND_ANY,
615                 .help = "at91samd flash command group",
616                 .usage = "",
617                 .chain = at91samd_exec_command_handlers,
618         },
619         COMMAND_REGISTRATION_DONE
620 };
621
622 struct flash_driver at91samd_flash = {
623         .name = "at91samd",
624         .commands = at91samd_command_handlers,
625         .flash_bank_command = samd_flash_bank_command,
626         .erase = samd_erase,
627         .protect = samd_protect,
628         .write = samd_write,
629         .read = default_flash_read,
630         .probe = samd_probe,
631         .auto_probe = samd_probe,
632         .erase_check = default_flash_blank_check,
633         .protect_check = samd_protect_check,
634 };