optimize: replace while loop by memcpy
[fw/openocd] / src / flash / nor / stm32lx.c
1 /***************************************************************************
2  *   Copyright (C) 2005 by Dominic Rath                                    *
3  *   Dominic.Rath@gmx.de                                                   *
4  *                                                                         *
5  *   Copyright (C) 2008 by Spencer Oliver                                  *
6  *   spen@spen-soft.co.uk                                                  *
7  *                                                                         *
8  *   Copyright (C) 2011 by Clement Burin des Roziers                       *
9  *   clement.burin-des-roziers@hikob.com                                   *
10  *                                                                         *
11  *   This program is free software; you can redistribute it and/or modify  *
12  *   it under the terms of the GNU General Public License as published by  *
13  *   the Free Software Foundation; either version 2 of the License, or     *
14  *   (at your option) any later version.                                   *
15  *                                                                         *
16  *   This program is distributed in the hope that it will be useful,       *
17  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
18  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
19  *   GNU General Public License for more details.                          *
20  *                                                                         *
21  *   You should have received a copy of the GNU General Public License     *
22  *   along with this program; if not, write to the                         *
23  *   Free Software Foundation, Inc.,                                       *
24  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
25  ***************************************************************************/
26 #ifdef HAVE_CONFIG_H
27 #include "config.h"
28 #endif
29
30 #include "imp.h"
31 #include <helper/binarybuffer.h>
32 #include <target/algorithm.h>
33 #include <target/armv7m.h>
34
35 /* stm32lx flash register locations */
36
37 #define FLASH_BASE              0x40023C00
38 #define FLASH_ACR               0x40023C00
39 #define FLASH_PECR              0x40023C04
40 #define FLASH_PDKEYR    0x40023C08
41 #define FLASH_PEKEYR    0x40023C0C
42 #define FLASH_PRGKEYR   0x40023C10
43 #define FLASH_OPTKEYR   0x40023C14
44 #define FLASH_SR                0x40023C18
45 #define FLASH_OBR               0x40023C1C
46 #define FLASH_WRPR              0x40023C20
47
48 /* FLASH_ACR bites */
49 #define FLASH_ACR__LATENCY              (1<<0)
50 #define FLASH_ACR__PRFTEN               (1<<1)
51 #define FLASH_ACR__ACC64                (1<<2)
52 #define FLASH_ACR__SLEEP_PD             (1<<3)
53 #define FLASH_ACR__RUN_PD               (1<<4)
54
55 /* FLASH_PECR bits */
56 #define FLASH_PECR__PELOCK              (1<<0)
57 #define FLASH_PECR__PRGLOCK             (1<<1)
58 #define FLASH_PECR__OPTLOCK             (1<<2)
59 #define FLASH_PECR__PROG                (1<<3)
60 #define FLASH_PECR__DATA                (1<<4)
61 #define FLASH_PECR__FTDW                (1<<8)
62 #define FLASH_PECR__ERASE               (1<<9)
63 #define FLASH_PECR__FPRG                (1<<10)
64 #define FLASH_PECR__EOPIE               (1<<16)
65 #define FLASH_PECR__ERRIE               (1<<17)
66 #define FLASH_PECR__OBL_LAUNCH  (1<<18)
67
68 /* FLASH_SR bits */
69 #define FLASH_SR__BSY           (1<<0)
70 #define FLASH_SR__EOP           (1<<1)
71 #define FLASH_SR__ENDHV         (1<<2)
72 #define FLASH_SR__READY         (1<<3)
73 #define FLASH_SR__WRPERR        (1<<8)
74 #define FLASH_SR__PGAERR        (1<<9)
75 #define FLASH_SR__SIZERR        (1<<10)
76 #define FLASH_SR__OPTVERR       (1<<11)
77
78 /* Unlock keys */
79 #define PEKEY1                  0x89ABCDEF
80 #define PEKEY2                  0x02030405
81 #define PRGKEY1                 0x8C9DAEBF
82 #define PRGKEY2                 0x13141516
83 #define OPTKEY1                 0xFBEAD9C8
84 #define OPTKEY2                 0x24252627
85
86 /* other registers */
87 #define DBGMCU_IDCODE   0xE0042000
88 #define F_SIZE                  0x1FF8004C
89
90 /* Constants */
91 #define FLASH_PAGE_SIZE 256
92 #define FLASH_SECTOR_SIZE 4096
93 #define FLASH_PAGES_PER_SECTOR 16
94 #define FLASH_BANK0_ADDRESS 0x08000000
95
96 /* stm32lx option byte register location */
97 #define OB_RDP                  0x1FF80000
98 #define OB_USER                 0x1FF80004
99 #define OB_WRP0_1               0x1FF80008
100 #define OB_WRP2_3               0x1FF8000C
101
102 /* OB_RDP values */
103 #define OB_RDP__LEVEL0  0xFF5500AA
104 #define OB_RDP__LEVEL1  0xFFFF0000
105
106 /* stm32lx RCC register locations */
107 #define RCC_CR          0x40023800
108 #define RCC_ICSCR       0x40023804
109 #define RCC_CFGR        0x40023808
110
111 /* RCC_ICSCR bits */
112 #define RCC_ICSCR__MSIRANGE_MASK        (7<<13)
113
114 static int stm32lx_unlock_program_memory(struct flash_bank *bank);
115 static int stm32lx_lock_program_memory(struct flash_bank *bank);
116 static int stm32lx_enable_write_half_page(struct flash_bank *bank);
117 static int stm32lx_erase_sector(struct flash_bank *bank, int sector);
118 static int stm32lx_wait_until_bsy_clear(struct flash_bank *bank);
119
120 struct stm32lx_flash_bank
121 {
122         struct working_area *write_algorithm;
123         int probed;
124 };
125
126 /* flash bank stm32lx <base> <size> 0 0 <target#>
127  */
128 FLASH_BANK_COMMAND_HANDLER(stm32lx_flash_bank_command)
129 {
130         struct stm32lx_flash_bank *stm32lx_info;
131         if (CMD_ARGC < 6)
132         {
133                 return ERROR_COMMAND_SYNTAX_ERROR;
134         }
135
136         // Create the bank structure
137         stm32lx_info = malloc(sizeof(struct stm32lx_flash_bank));
138
139         // Check allocation
140         if (stm32lx_info == NULL)
141         {
142                 LOG_ERROR("failed to allocate bank structure");
143                 return ERROR_FAIL;
144         }
145
146         bank->driver_priv = stm32lx_info;
147
148         stm32lx_info->write_algorithm = NULL;
149         stm32lx_info->probed = 0;
150
151         return ERROR_OK;
152 }
153
154 static int stm32lx_protect_check(struct flash_bank *bank)
155 {
156         int retval;
157         struct target *target = bank->target;
158
159         uint32_t wrpr;
160
161         if (target->state != TARGET_HALTED)
162         {
163                 LOG_ERROR("Target not halted");
164                 return ERROR_TARGET_NOT_HALTED;
165         }
166
167         /*
168          * Read the WRPR word, and check each bit (corresponding to each
169          * flash sector
170          */
171         retval = target_read_u32(target, FLASH_WRPR, &wrpr);
172         if (retval != ERROR_OK)
173                 return retval;
174
175         for (int i = 0; i < 32; i++)
176         {
177                 if (wrpr & (1 << i))
178                 {
179                         bank->sectors[i].is_protected = 1;
180                 }
181                 else
182                 {
183                         bank->sectors[i].is_protected = 0;
184                 }
185         }
186         return ERROR_OK;
187 }
188
189 static int stm32lx_erase(struct flash_bank *bank, int first, int last)
190 {
191         int retval;
192
193         /*
194          * It could be possible to do a mass erase if all sectors must be
195          * erased, but it is not implemented yet.
196          */
197
198         if (bank->target->state != TARGET_HALTED)
199         {
200                 LOG_ERROR("Target not halted");
201                 return ERROR_TARGET_NOT_HALTED;
202         }
203
204         /*
205          * Loop over the selected sectors and erase them
206          */
207         for (int i = first; i <= last; i++)
208         {
209                 retval = stm32lx_erase_sector(bank, i);
210                 if (retval != ERROR_OK)
211                         return retval;
212                 bank->sectors[i].is_erased = 1;
213         }
214         return ERROR_OK;
215 }
216
217 static int stm32lx_protect(struct flash_bank *bank, int set, int first,
218                 int last)
219 {
220         LOG_WARNING("protection of the STM32L flash is not implemented");
221         return ERROR_OK;
222 }
223
224 static int stm32lx_write_half_pages(struct flash_bank *bank, uint8_t *buffer,
225                 uint32_t offset, uint32_t count)
226 {
227         struct stm32lx_flash_bank *stm32lx_info = bank->driver_priv;
228         struct target *target = bank->target;
229         uint32_t buffer_size = 4096 * 4;
230         struct working_area *source;
231         uint32_t address = bank->base + offset;
232
233         struct reg_param reg_params[5];
234         struct armv7m_algorithm armv7m_info;
235
236         int retval = ERROR_OK;
237         uint32_t reg32;
238
239         /* see contib/loaders/flash/stm32lx.s for src */
240
241         static const uint16_t stm32lx_flash_write_code_16[] =
242         {
243         //      00000000 <write_word-0x4>:
244                         0x2300, // 0:   2300            movs    r3, #0
245                         0xe004, // 2:   e004            b.n     e <test_done>
246
247                         //      00000004 <write_word>:
248                         0xf851, 0xcb04, // 4:   f851 cb04       ldr.w   ip, [r1], #4
249                         0xf840, 0xcb04, // 8:   f840 cb04       str.w   ip, [r0], #4
250                         0x3301, // c:   3301            adds    r3, #1
251
252                         //      0000000e <test_done>:
253                         0x4293, // e:   4293            cmp     r3, r2
254                         0xd3f8, // 10:  d3f8            bcc.n   4 <write_word>
255                         0xbe00, // 12:  be00            bkpt    0x0000
256
257                         };
258
259         // Flip endian
260         uint8_t stm32lx_flash_write_code[sizeof(stm32lx_flash_write_code_16)];
261         for (unsigned int i = 0; i < sizeof(stm32lx_flash_write_code_16) / 2; i++)
262         {
263                 stm32lx_flash_write_code[i * 2 + 0] = stm32lx_flash_write_code_16[i]
264                                 & 0xff;
265                 stm32lx_flash_write_code[i * 2 + 1] = (stm32lx_flash_write_code_16[i]
266                                 >> 8) & 0xff;
267         }
268         // Check if there is an even number of half pages (128bytes)
269         if (count % 128)
270         {
271                 LOG_ERROR("there should be an even number "
272                                 "of half pages = 128 bytes (count = %" PRIi32 " bytes)", count);
273                 return ERROR_FAIL;
274         }
275
276         // Allocate working area
277         reg32 = sizeof(stm32lx_flash_write_code);
278         // Add bytes to make 4byte aligned
279         reg32 += (4 - (reg32 % 4)) % 4;
280         retval = target_alloc_working_area(target, reg32,
281                         &stm32lx_info->write_algorithm);
282         if (retval != ERROR_OK)
283                 return retval;
284
285         // Write the flashing code
286         retval = target_write_buffer(target,
287                         stm32lx_info->write_algorithm->address,
288                         sizeof(stm32lx_flash_write_code),
289                         (uint8_t*) stm32lx_flash_write_code);
290         if (retval != ERROR_OK)
291         {
292                 target_free_working_area(target, stm32lx_info->write_algorithm);
293                 return retval;
294         }
295
296         // Allocate half pages memory
297         while (target_alloc_working_area_try(target, buffer_size, &source)
298                         != ERROR_OK)
299         {
300                 if (buffer_size > 1024)
301                         buffer_size -= 1024;
302                 else
303                         buffer_size /= 2;
304
305                 if (buffer_size <= 256)
306                 {
307                         /* if we already allocated the writing code, but failed to get a
308                          * buffer, free the algorithm */
309                         if (stm32lx_info->write_algorithm)
310                                 target_free_working_area(target, stm32lx_info->write_algorithm);
311
312                         LOG_WARNING("no large enough working area available, can't do block memory writes");
313                         return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
314                 }
315         }
316         LOG_DEBUG("allocated working area for data (%" PRIx32 " bytes)", buffer_size);
317
318         armv7m_info.common_magic = ARMV7M_COMMON_MAGIC;
319         armv7m_info.core_mode = ARMV7M_MODE_ANY;
320         init_reg_param(&reg_params[0], "r0", 32, PARAM_OUT);
321         init_reg_param(&reg_params[1], "r1", 32, PARAM_OUT);
322         init_reg_param(&reg_params[2], "r2", 32, PARAM_OUT);
323         init_reg_param(&reg_params[3], "r3", 32, PARAM_IN_OUT);
324         init_reg_param(&reg_params[4], "r4", 32, PARAM_OUT);
325
326         // Enable half-page write
327         retval = stm32lx_enable_write_half_page(bank);
328         if (retval != ERROR_OK)
329         {
330
331                 target_free_working_area(target, source);
332                 target_free_working_area(target, stm32lx_info->write_algorithm);
333
334                 destroy_reg_param(&reg_params[0]);
335                 destroy_reg_param(&reg_params[1]);
336                 destroy_reg_param(&reg_params[2]);
337                 destroy_reg_param(&reg_params[3]);
338
339                 return retval;
340         }
341
342         // Loop while there are bytes to write
343         while (count > 0)
344         {
345                 uint32_t this_count;
346                 this_count = (count > buffer_size) ? buffer_size : count;
347
348                 // Write the next half pages
349                 retval = target_write_buffer(target, source->address, this_count,
350                                 buffer);
351                 if (retval != ERROR_OK)
352                         break;
353
354                 // 4: Store useful information in the registers
355                 // the destination address of the copy (R0)
356                 buf_set_u32(reg_params[0].value, 0, 32, address);
357                 // The source address of the copy (R1)
358                 buf_set_u32(reg_params[1].value, 0, 32, source->address);
359                 // The length of the copy (R2)
360                 buf_set_u32(reg_params[2].value, 0, 32, this_count / 4);
361
362                 // 5: Execute the bunch of code
363                 retval = target_run_algorithm(target, 0, NULL, sizeof(reg_params)
364                                 / sizeof(*reg_params), reg_params,
365                                 stm32lx_info->write_algorithm->address, 0, 20000, &armv7m_info);
366                 if (retval != ERROR_OK)
367                         break;
368
369                 // 6: Wait while busy
370                 retval = stm32lx_wait_until_bsy_clear(bank);
371                 if (retval != ERROR_OK)
372                         break;
373
374                 buffer += this_count;
375                 address += this_count;
376                 count -= this_count;
377         }
378
379         if (retval == ERROR_OK)
380                 retval = stm32lx_lock_program_memory(bank);
381
382         target_free_working_area(target, source);
383         target_free_working_area(target, stm32lx_info->write_algorithm);
384
385         destroy_reg_param(&reg_params[0]);
386         destroy_reg_param(&reg_params[1]);
387         destroy_reg_param(&reg_params[2]);
388         destroy_reg_param(&reg_params[3]);
389
390         return retval;
391 }
392 static int stm32lx_write(struct flash_bank *bank, uint8_t *buffer,
393                 uint32_t offset, uint32_t count)
394 {
395         struct target *target = bank->target;
396
397         uint32_t halfpages_number;
398         uint32_t words_remaining;
399         uint32_t bytes_remaining;
400         uint32_t address = bank->base + offset;
401         uint32_t bytes_written = 0;
402         int retval;
403
404         if (bank->target->state != TARGET_HALTED)
405         {
406                 LOG_ERROR("Target not halted");
407                 return ERROR_TARGET_NOT_HALTED;
408         }
409
410         if (offset & 0x1)
411         {
412                 LOG_ERROR("offset 0x%" PRIx32 " breaks required 2-byte alignment", offset);
413                 return ERROR_FLASH_DST_BREAKS_ALIGNMENT;
414         }
415
416         // Check if there are some full half pages
417         if (((offset % 128) == 0) && (count >= 128))
418         {
419                 halfpages_number = count / 128;
420                 words_remaining = (count - 128 * halfpages_number) / 4;
421                 bytes_remaining = (count & 0x3);
422         }
423         else
424         {
425                 halfpages_number = 0;
426                 words_remaining = (count / 4);
427                 bytes_remaining = (count & 0x3);
428         }
429
430         if (halfpages_number)
431         {
432                 retval = stm32lx_write_half_pages(bank, buffer, offset, 128
433                                 * halfpages_number);
434                 if (retval != ERROR_OK)
435                         return ERROR_FAIL;
436         }
437
438         bytes_written = 128 * halfpages_number;
439
440         retval = stm32lx_unlock_program_memory(bank);
441         if (retval != ERROR_OK)
442                 return retval;
443
444         while (words_remaining > 0)
445         {
446                 uint32_t value;
447                 uint8_t* p = buffer + bytes_written;
448
449                 // Prepare the word, Little endian conversion
450                 value = p[0] + (p[1] << 8) + (p[2] << 16) + (p[3] << 24);
451
452                 retval = target_write_u32(target, address, value);
453                 if (retval != ERROR_OK)
454                         return retval;
455
456                 bytes_written += 4;
457                 words_remaining--;
458                 address += 4;
459
460                 retval = stm32lx_wait_until_bsy_clear(bank);
461                 if (retval != ERROR_OK)
462                         return retval;
463         }
464
465         if (bytes_remaining)
466         {
467                 uint8_t last_word[4] = {0xff, 0xff, 0xff, 0xff};
468
469                 /* copy the last remaining bytes into the write buffer */
470                 memcpy(last_word, buffer+bytes_written, bytes_remaining);
471
472                 retval = target_write_buffer(target, address, 4, last_word);
473                 if (retval != ERROR_OK)
474                         return retval;
475
476                 retval = stm32lx_wait_until_bsy_clear(bank);
477                 if (retval != ERROR_OK)
478                         return retval;
479         }
480
481         retval = stm32lx_lock_program_memory(bank);
482         if (retval != ERROR_OK)
483                 return retval;
484
485         return ERROR_OK;
486 }
487
488 static int stm32lx_probe(struct flash_bank *bank)
489 {
490         struct target *target = bank->target;
491         struct stm32lx_flash_bank *stm32lx_info = bank->driver_priv;
492         int i;
493         uint16_t flash_size;
494         uint32_t device_id;
495         uint32_t reg32;
496
497         stm32lx_info->probed = 0;
498
499         /* read stm32 device id register */
500         int retval = target_read_u32(target, DBGMCU_IDCODE, &device_id);
501         if (retval != ERROR_OK)
502                 return retval;
503
504         LOG_DEBUG("device id = 0x%08" PRIx32 "", device_id);
505
506         if ((device_id & 0x7ff) != 0x416)
507         {
508                 LOG_WARNING("Cannot identify target as a STM32L family.");
509                 return ERROR_FAIL;
510         }
511
512         // Read the RDP byte and check if it is 0xAA
513         uint8_t rdp;
514         retval = target_read_u32(target, FLASH_OBR, &reg32);
515         if (retval != ERROR_OK)
516                 return retval;
517         rdp = reg32 & 0xFF;
518         if (rdp != 0xAA)
519         {
520                 /*
521                  * Unlocking the option byte is done by unlocking the PECR, then
522                  * by writing the 2 option byte keys to OPTKEYR
523                  */
524
525                 /* To unlock the PECR write the 2 PEKEY to the PEKEYR register */
526                 retval = target_write_u32(target, FLASH_PEKEYR, PEKEY1);
527                 if (retval != ERROR_OK)
528                         return retval;
529
530                 retval = target_write_u32(target, FLASH_PEKEYR, PEKEY2);
531                 if (retval != ERROR_OK)
532                         return retval;
533
534                 /* Make sure it worked */
535                 retval = target_read_u32(target, FLASH_PECR, &reg32);
536                 if (retval != ERROR_OK)
537                         return retval;
538
539                 if (reg32 & FLASH_PECR__PELOCK)
540                         return ERROR_FLASH_OPERATION_FAILED;
541
542                 retval = target_write_u32(target, FLASH_OPTKEYR, OPTKEY1);
543                 if (retval != ERROR_OK)
544                         return retval;
545                 retval = target_write_u32(target, FLASH_OPTKEYR, OPTKEY2);
546                 if (retval != ERROR_OK)
547                         return retval;
548
549                 retval = target_read_u32(target, FLASH_PECR, &reg32);
550                 if (retval != ERROR_OK)
551                         return retval;
552
553                 if (reg32 & FLASH_PECR__OPTLOCK)
554                 {
555                         LOG_ERROR("OPTLOCK is not cleared");
556                         return ERROR_FLASH_OPERATION_FAILED;
557                 }
558
559                 // Then, write RDP to 0x00 to set level 1
560                 reg32 = ((~0xAA) << 16) | (0xAA);
561                 retval = target_write_u32(target, OB_RDP, reg32);
562                 if (retval != ERROR_OK)
563                         return retval;
564
565                 // Set Automatic update of the option byte, by setting OBL_LAUNCH in FLASH_PECR
566                 reg32 = FLASH_PECR__OBL_LAUNCH;
567                 retval = target_write_u32(target, FLASH_PECR, reg32);
568                 if (retval != ERROR_OK)
569                         return retval;
570         }
571
572         /* get flash size from target. */
573         retval = target_read_u16(target, F_SIZE, &flash_size);
574         if (retval != ERROR_OK)
575                 return retval;
576
577         /* check for valid flash size */
578         if (flash_size == 0xffff)
579         {
580                 /* number of sectors incorrect on revA */
581                 LOG_ERROR("STM32 flash size failed, probe inaccurate");
582                 return ERROR_FAIL;
583         }
584
585         /* STM32L - we have 32 sectors, 16 pages per sector -> 512 pages
586          * 16 pages for a protection area */
587
588         /* calculate numbers of sectors (4kB per sector) */
589         int num_sectors = (flash_size * 1024) / FLASH_SECTOR_SIZE;
590         LOG_INFO("flash size = %dkbytes", flash_size);
591
592         if (bank->sectors)
593         {
594                 free(bank->sectors);
595                 bank->sectors = NULL;
596         }
597
598         bank->base = FLASH_BANK0_ADDRESS;
599         bank->size = flash_size * 1024;
600         bank->num_sectors = num_sectors;
601         bank->sectors = malloc(sizeof(struct flash_sector) * num_sectors);
602         if (bank->sectors == NULL)
603         {
604                 LOG_ERROR("failed to allocate bank sectors");
605                 return ERROR_FAIL;
606         }
607
608         for (i = 0; i < num_sectors; i++)
609         {
610                 bank->sectors[i].offset = i * FLASH_SECTOR_SIZE;
611                 bank->sectors[i].size = FLASH_SECTOR_SIZE;
612                 bank->sectors[i].is_erased = -1;
613                 bank->sectors[i].is_protected = 1;
614         }
615
616         stm32lx_info->probed = 1;
617
618         return ERROR_OK;
619 }
620
621 static int stm32lx_auto_probe(struct flash_bank *bank)
622 {
623         struct stm32lx_flash_bank *stm32lx_info = bank->driver_priv;
624
625         if (stm32lx_info->probed)
626         {
627                 return ERROR_OK;
628         }
629
630         return stm32lx_probe(bank);
631 }
632
633 static int stm32lx_erase_check(struct flash_bank *bank)
634 {
635         struct target *target = bank->target;
636         const int buffer_size = 4096;
637         int i;
638         uint32_t nBytes;
639         int retval = ERROR_OK;
640
641         if (bank->target->state != TARGET_HALTED)
642         {
643                 LOG_ERROR("Target not halted");
644                 return ERROR_TARGET_NOT_HALTED;
645         }
646
647         uint8_t *buffer = malloc(buffer_size);
648         if (buffer == NULL)
649         {
650                 LOG_ERROR("failed to allocate read buffer");
651                 return ERROR_FAIL;
652         }
653
654         for (i = 0; i < bank->num_sectors; i++)
655         {
656                 uint32_t j;
657                 bank->sectors[i].is_erased = 1;
658
659                 // Loop chunk by chunk over the sector
660                 for (j = 0; j < bank->sectors[i].size; j += buffer_size)
661                 {
662                         uint32_t chunk;
663                         chunk = buffer_size;
664                         if (chunk > (j - bank->sectors[i].size))
665                         {
666                                 chunk = (j - bank->sectors[i].size);
667                         }
668
669                         retval = target_read_memory(target, bank->base
670                                         + bank->sectors[i].offset + j, 4, chunk / 4, buffer);
671                         if (retval != ERROR_OK)
672                                 break;
673
674                         for (nBytes = 0; nBytes < chunk; nBytes++)
675                         {
676                                 if (buffer[nBytes] != 0x00)
677                                 {
678                                         bank->sectors[i].is_erased = 0;
679                                         break;
680                                 }
681                         }
682                 }
683                 if (retval != ERROR_OK)
684                 {
685                         break;
686                 }
687         }
688         free(buffer);
689
690         return retval;
691 }
692 static int stm32lx_get_info(struct flash_bank *bank, char *buf, int buf_size)
693 {
694         // This method must return a string displaying information about the bank
695
696         struct target *target = bank->target;
697         uint32_t device_id;
698         int printed;
699
700         /* read stm32 device id register */
701         int retval = target_read_u32(target, DBGMCU_IDCODE, &device_id);
702         if (retval != ERROR_OK)
703                 return retval;
704
705         if ((device_id & 0x7ff) == 0x416)
706         {
707                 printed = snprintf(buf, buf_size, "stm32lx - Rev: ");
708                 buf += printed;
709                 buf_size -= printed;
710
711                 switch (device_id >> 16)
712                 {
713                         case 0x1000:
714                                 snprintf(buf, buf_size, "A");
715                                 break;
716
717                         case 0x1008:
718                                 snprintf(buf, buf_size, "Y");
719                                 break;
720                         default:
721                                 snprintf(buf, buf_size, "unknown");
722                                 break;
723                 }
724         }
725         else
726         {
727                 snprintf(buf, buf_size, "Cannot identify target as a stm32lx");
728                 return ERROR_FAIL;
729         }
730
731         return ERROR_OK;
732 }
733
734 static const struct command_registration stm32lx_exec_command_handlers[] =
735 {
736         COMMAND_REGISTRATION_DONE
737 };
738
739 static const struct command_registration stm32lx_command_handlers[] =
740 {
741         {
742                 .name = "stm32lx",
743                 .mode = COMMAND_ANY,
744                 .help = "stm32lx flash command group",
745                 .chain = stm32lx_exec_command_handlers,
746         },
747         COMMAND_REGISTRATION_DONE
748 };
749
750 struct flash_driver stm32lx_flash =
751 {
752                 .name = "stm32lx",
753                 .commands = stm32lx_command_handlers,
754                 .flash_bank_command = stm32lx_flash_bank_command,
755                 .erase = stm32lx_erase,
756                 .protect = stm32lx_protect,
757                 .write = stm32lx_write,
758                 .read = default_flash_read,
759                 .probe = stm32lx_probe,
760                 .auto_probe = stm32lx_auto_probe,
761                 .erase_check = stm32lx_erase_check,
762                 .protect_check = stm32lx_protect_check,
763                 .info = stm32lx_get_info,
764 };
765
766 // Static methods implementation
767
768 static int stm32lx_unlock_program_memory(struct flash_bank *bank)
769 {
770         struct target *target = bank->target;
771         int retval;
772         uint32_t reg32;
773
774         /*
775          * Unlocking the program memory is done by unlocking the PECR,
776          * then by writing the 2 PRGKEY to the PRGKEYR register
777          */
778
779         /* To unlock the PECR write the 2 PEKEY to the PEKEYR register */
780         retval = target_write_u32(target, FLASH_PEKEYR, PEKEY1);
781         if (retval != ERROR_OK)
782                 return retval;
783
784         retval = target_write_u32(target, FLASH_PEKEYR, PEKEY2);
785         if (retval != ERROR_OK)
786                 return retval;
787
788         /* Make sure it worked */
789         retval = target_read_u32(target, FLASH_PECR, &reg32);
790         if (retval != ERROR_OK)
791                 return retval;
792
793         if (reg32 & FLASH_PECR__PELOCK)
794         {
795                 LOG_ERROR("PELOCK is not cleared :(");
796                 return ERROR_FLASH_OPERATION_FAILED;
797         }
798
799         retval = target_write_u32(target, FLASH_PRGKEYR, PRGKEY1);
800         if (retval != ERROR_OK)
801                 return retval;
802         retval = target_write_u32(target, FLASH_PRGKEYR, PRGKEY2);
803         if (retval != ERROR_OK)
804                 return retval;
805
806         /* Make sure it worked */
807         retval = target_read_u32(target, FLASH_PECR, &reg32);
808         if (retval != ERROR_OK)
809                 return retval;
810
811         if (reg32 & FLASH_PECR__PRGLOCK)
812         {
813                 LOG_ERROR("PRGLOCK is not cleared :(");
814                 return ERROR_FLASH_OPERATION_FAILED;
815         }
816         return ERROR_OK;
817 }
818
819 static int stm32lx_enable_write_half_page(struct flash_bank *bank)
820 {
821         struct target *target = bank->target;
822         int retval;
823         uint32_t reg32;
824
825         /**
826          * Unlock the program memory, then set the FPRG bit in the PECR register.
827          */
828         retval = stm32lx_unlock_program_memory(bank);
829         if (retval != ERROR_OK)
830                 return retval;
831
832         retval = target_read_u32(target, FLASH_PECR, &reg32);
833         if (retval != ERROR_OK)
834                 return retval;
835
836         reg32 |= FLASH_PECR__FPRG;
837         retval = target_write_u32(target, FLASH_PECR, reg32);
838         if (retval != ERROR_OK)
839                 return retval;
840
841         retval = target_read_u32(target, FLASH_PECR, &reg32);
842         if (retval != ERROR_OK)
843                 return retval;
844
845         reg32 |= FLASH_PECR__PROG;
846         retval = target_write_u32(target, FLASH_PECR, reg32);
847
848         return retval;
849 }
850
851 static int stm32lx_lock_program_memory(struct flash_bank *bank)
852 {
853         struct target *target = bank->target;
854         int retval;
855         uint32_t reg32;
856
857         /* To lock the program memory, simply set the lock bit and lock PECR */
858
859         retval = target_read_u32(target, FLASH_PECR, &reg32);
860         if (retval != ERROR_OK)
861                 return retval;
862
863         reg32 |= FLASH_PECR__PRGLOCK;
864         retval = target_write_u32(target, FLASH_PECR, reg32);
865         if (retval != ERROR_OK)
866                 return retval;
867
868         retval = target_read_u32(target, FLASH_PECR, &reg32);
869         if (retval != ERROR_OK)
870                 return retval;
871
872         reg32 |= FLASH_PECR__PELOCK;
873         retval = target_write_u32(target, FLASH_PECR, reg32);
874         if (retval != ERROR_OK)
875                 return retval;
876
877         return ERROR_OK;
878 }
879
880 static int stm32lx_erase_sector(struct flash_bank *bank, int sector)
881 {
882         struct target *target = bank->target;
883         int retval;
884         uint32_t reg32;
885
886         /*
887          * To erase a sector (i.e. FLASH_PAGES_PER_SECTOR pages),
888          * first unlock the memory, loop over the pages of this sector
889          * and write 0x0 to its first word.
890          */
891
892         retval = stm32lx_unlock_program_memory(bank);
893         if (retval != ERROR_OK)
894                 return retval;
895
896         for (int page = 0; page < FLASH_PAGES_PER_SECTOR; page++)
897         {
898                 reg32 = FLASH_PECR__PROG | FLASH_PECR__ERASE;
899                 retval = target_write_u32(target, FLASH_PECR, reg32);
900                 if (retval != ERROR_OK)
901                         return retval;
902
903                 retval = stm32lx_wait_until_bsy_clear(bank);
904                 if (retval != ERROR_OK)
905                         return retval;
906
907                 uint32_t addr = bank->base + bank->sectors[sector].offset + (page
908                                 * FLASH_PAGE_SIZE);
909                 retval = target_write_u32(target, addr, 0x0);
910                 if (retval != ERROR_OK)
911                         return retval;
912
913                 retval = stm32lx_wait_until_bsy_clear(bank);
914                 if (retval != ERROR_OK)
915                         return retval;
916         }
917
918         retval = stm32lx_lock_program_memory(bank);
919         if (retval != ERROR_OK)
920                 return retval;
921
922         return ERROR_OK;
923 }
924
925 static int stm32lx_wait_until_bsy_clear(struct flash_bank *bank)
926 {
927         struct target *target = bank->target;
928         uint32_t status;
929         int retval = ERROR_OK;
930         int timeout = 100;
931
932         /* wait for busy to clear */
933         for (;;)
934         {
935                 retval = target_read_u32(target, FLASH_SR, &status);
936                 if (retval != ERROR_OK)
937                         return retval;
938
939                 if ((status & FLASH_SR__BSY) == 0)
940                 {
941                         break;
942                 }
943                 if (timeout-- <= 0)
944                 {
945                         LOG_ERROR("timed out waiting for flash");
946                         return ERROR_FAIL;
947                 }
948                 alive_sleep(1);
949         }
950
951         if (status & FLASH_SR__WRPERR)
952         {
953                 LOG_ERROR("access denied / write protected");
954                 retval = ERROR_FAIL;
955         }
956
957         if (status & FLASH_SR__PGAERR)
958         {
959                 LOG_ERROR("invalid program address");
960                 retval = ERROR_FAIL;
961         }
962
963         return retval;
964 }