aboutsummaryrefslogtreecommitdiff
path: root/platform/stm32f7xx/qspi.c
blob: 482be26e7a8cfa177d5243ce60e6249efed6973c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
/*
 * Copyright (c) 2015 Gurjant Kalsi <me@gurjantkalsi.com>
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files
 * (the "Software"), to deal in the Software without restriction,
 * including without limitation the rights to use, copy, modify, merge,
 * publish, distribute, sublicense, and/or sell copies of the Software,
 * and to permit persons to whom the Software is furnished to do so,
 * subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */
#include <err.h>
#include <pow2.h>
#include <stdlib.h>
#include <string.h>

#include <arch/arm/cm.h>
#include <kernel/event.h>
#include <kernel/mutex.h>
#include <lib/bio.h>
#include <platform/n25qxxa.h>
#include <platform/n25q512a.h>
#include <platform/qspi.h>

#define FOUR_BYTE_ADDR_THRESHOLD (1 << 24)

static QSPI_HandleTypeDef qspi_handle;
static DMA_HandleTypeDef hdma;

static const char device_name[] = "qspi-flash";
static bdev_t qspi_flash_device;
static bio_erase_geometry_info_t geometry;

static mutex_t spiflash_mutex;

// Functions exported to Block I/O handler.
static ssize_t spiflash_bdev_read(struct bdev* device, void* buf, off_t offset, size_t len);
static ssize_t spiflash_bdev_read_block(struct bdev* device, void* buf, bnum_t block, uint count);
static ssize_t spiflash_bdev_write_block(struct bdev* device, const void* buf, bnum_t block, uint count);
static ssize_t spiflash_bdev_erase(struct bdev* device, off_t offset, size_t len);
static int spiflash_ioctl(struct bdev* device, int request, void* argp);

static ssize_t qspi_write_page_unsafe(uint32_t addr, const uint8_t *data);

static ssize_t qspi_erase(bdev_t *device, uint32_t block_addr, uint32_t instruction);
static ssize_t qspi_bulk_erase(bdev_t *device);
static ssize_t qspi_erase_sector(bdev_t *device, uint32_t block_addr);
static ssize_t qspi_erase_subsector(bdev_t *device, uint32_t block_addr);

static HAL_StatusTypeDef qspi_cmd(QSPI_HandleTypeDef*, QSPI_CommandTypeDef*);
static HAL_StatusTypeDef qspi_tx_dma(QSPI_HandleTypeDef*, QSPI_CommandTypeDef*, uint8_t*);
static HAL_StatusTypeDef qspi_rx_dma(QSPI_HandleTypeDef*, QSPI_CommandTypeDef*, uint8_t*);

status_t qspi_enable_linear(void);

status_t qspi_dma_init(QSPI_HandleTypeDef *hqspi);

static uint32_t get_specialized_instruction(uint32_t instruction, uint32_t address);
static uint32_t get_address_size(uint32_t address);

static event_t cmd_event;
static event_t rx_event;
static event_t tx_event;

status_t hal_error_to_status(HAL_StatusTypeDef hal_status);

// Must hold spiflash_mutex before calling.
static status_t qspi_write_enable_unsafe(QSPI_HandleTypeDef* hqspi)
{
    QSPI_CommandTypeDef s_command;
    QSPI_AutoPollingTypeDef s_config;
    HAL_StatusTypeDef status;

    /* Enable write operations */
    s_command.InstructionMode = QSPI_INSTRUCTION_1_LINE;
    s_command.Instruction = WRITE_ENABLE_CMD;
    s_command.AddressMode = QSPI_ADDRESS_NONE;
    s_command.AlternateByteMode = QSPI_ALTERNATE_BYTES_NONE;
    s_command.DataMode = QSPI_DATA_NONE;
    s_command.DummyCycles = 0;
    s_command.DdrMode = QSPI_DDR_MODE_DISABLE;
    s_command.DdrHoldHalfCycle = QSPI_DDR_HHC_ANALOG_DELAY;
    s_command.SIOOMode = QSPI_SIOO_INST_EVERY_CMD;

    status = HAL_QSPI_Command(hqspi, &s_command, HAL_QPSI_TIMEOUT_DEFAULT_VALUE);
    if (status != HAL_OK) {
        return hal_error_to_status(status);
    }

    /* Configure automatic polling mode to wait for write enabling */
    s_config.Match = N25QXXA_SR_WREN;
    s_config.Mask = N25QXXA_SR_WREN;
    s_config.MatchMode = QSPI_MATCH_MODE_AND;
    s_config.StatusBytesSize = 1;
    s_config.Interval = 0x10;
    s_config.AutomaticStop = QSPI_AUTOMATIC_STOP_ENABLE;

    s_command.Instruction = READ_STATUS_REG_CMD;
    s_command.DataMode = QSPI_DATA_1_LINE;

    status = HAL_QSPI_AutoPolling(hqspi, &s_command, &s_config, HAL_QPSI_TIMEOUT_DEFAULT_VALUE);
    if (status != HAL_OK) {
        return hal_error_to_status(status);
    }

    return NO_ERROR;
}

// Must hold spiflash_mutex before calling.
static status_t qspi_dummy_cycles_cfg_unsafe(QSPI_HandleTypeDef* hqspi)
{
    QSPI_CommandTypeDef s_command;
    uint8_t reg;
    HAL_StatusTypeDef status;

    /* Initialize the read volatile configuration register command */
    s_command.InstructionMode = QSPI_INSTRUCTION_1_LINE;
    s_command.Instruction = READ_VOL_CFG_REG_CMD;
    s_command.AddressMode = QSPI_ADDRESS_NONE;
    s_command.AlternateByteMode = QSPI_ALTERNATE_BYTES_NONE;
    s_command.DataMode = QSPI_DATA_1_LINE;
    s_command.DummyCycles = 0;
    s_command.NbData = 1;
    s_command.DdrMode = QSPI_DDR_MODE_DISABLE;
    s_command.DdrHoldHalfCycle = QSPI_DDR_HHC_ANALOG_DELAY;
    s_command.SIOOMode = QSPI_SIOO_INST_EVERY_CMD;

    /* Configure the command */
    status = HAL_QSPI_Command(hqspi, &s_command, HAL_QPSI_TIMEOUT_DEFAULT_VALUE);
    if (status != HAL_OK) {
        return hal_error_to_status(status);
    }

    /* Reception of the data */
    status = HAL_QSPI_Receive(hqspi, &reg, HAL_QPSI_TIMEOUT_DEFAULT_VALUE);
    if (status != HAL_OK) {
        return hal_error_to_status(status);
    }

    /* Enable write operations */
    status = qspi_write_enable_unsafe(hqspi);
    if (status != NO_ERROR) {
        return status;
    }

    /* Update volatile configuration register (with new dummy cycles) */
    s_command.Instruction = WRITE_VOL_CFG_REG_CMD;
    MODIFY_REG(
        reg, N25QXXA_VCR_NB_DUMMY,
        (N25QXXA_DUMMY_CYCLES_READ_QUAD << POSITION_VAL(N25QXXA_VCR_NB_DUMMY)));

    /* Configure the write volatile configuration register command */
    status = HAL_QSPI_Command(hqspi, &s_command, HAL_QPSI_TIMEOUT_DEFAULT_VALUE);
    if (status != HAL_OK) {
        return hal_error_to_status(status);
    }

    /* Transmission of the data */
    status = HAL_QSPI_Transmit(hqspi, &reg, HAL_QPSI_TIMEOUT_DEFAULT_VALUE);
    if (status != HAL_OK) {
        return hal_error_to_status(status);
    }

    return NO_ERROR;
}

// Must hold spiflash_mutex before calling.
static status_t qspi_auto_polling_mem_ready_unsafe(QSPI_HandleTypeDef* hqspi)
{
    QSPI_CommandTypeDef s_command;
    QSPI_AutoPollingTypeDef s_config;
    HAL_StatusTypeDef status;

    /* Configure automatic polling mode to wait for memory ready */
    s_command.InstructionMode = QSPI_INSTRUCTION_1_LINE;
    s_command.Instruction = READ_STATUS_REG_CMD;
    s_command.AddressMode = QSPI_ADDRESS_NONE;
    s_command.AlternateByteMode = QSPI_ALTERNATE_BYTES_NONE;
    s_command.DataMode = QSPI_DATA_1_LINE;
    s_command.DummyCycles = 0;
    s_command.DdrMode = QSPI_DDR_MODE_DISABLE;
    s_command.DdrHoldHalfCycle = QSPI_DDR_HHC_ANALOG_DELAY;
    s_command.SIOOMode = QSPI_SIOO_INST_EVERY_CMD;

    s_config.Match = 0;
    s_config.Mask = N25QXXA_SR_WIP;
    s_config.MatchMode = QSPI_MATCH_MODE_AND;
    s_config.StatusBytesSize = 1;
    s_config.Interval = 0x10;
    s_config.AutomaticStop = QSPI_AUTOMATIC_STOP_ENABLE;

    status = HAL_QSPI_AutoPolling_IT(hqspi, &s_command, &s_config);
    if (status != HAL_OK) {
        return hal_error_to_status(status);
    }

    return NO_ERROR;
}

// Must hold spiflash_mutex before calling.
static status_t qspi_reset_memory_unsafe(QSPI_HandleTypeDef* hqspi)
{
    QSPI_CommandTypeDef s_command;
    HAL_StatusTypeDef status;

    /* Initialize the reset enable command */
    s_command.InstructionMode = QSPI_INSTRUCTION_1_LINE;
    s_command.Instruction = RESET_ENABLE_CMD;
    s_command.AddressMode = QSPI_ADDRESS_NONE;
    s_command.AlternateByteMode = QSPI_ALTERNATE_BYTES_NONE;
    s_command.DataMode = QSPI_DATA_NONE;
    s_command.DummyCycles = 0;
    s_command.DdrMode = QSPI_DDR_MODE_DISABLE;
    s_command.DdrHoldHalfCycle = QSPI_DDR_HHC_ANALOG_DELAY;
    s_command.SIOOMode = QSPI_SIOO_INST_EVERY_CMD;

    /* Send the command */
    status = qspi_cmd(hqspi, &s_command);
    if (status != HAL_OK) {
        return hal_error_to_status(status);
    }

    /* Send the reset memory command */
    s_command.Instruction = RESET_MEMORY_CMD;
    status = qspi_cmd(hqspi, &s_command);
    if (status != HAL_OK) {
        return hal_error_to_status(status);
    }

    /* Configure automatic polling mode to wait the memory is ready */
    status = qspi_auto_polling_mem_ready_unsafe(hqspi);
    if (status != NO_ERROR) {
        return hal_error_to_status(status);
    }

    return NO_ERROR;
}

static ssize_t spiflash_bdev_read(struct bdev* device, void* buf, off_t offset, size_t len)
{
    len = bio_trim_range(device, offset, len);
    if (len == 0) {
        return 0;
    }

    QSPI_CommandTypeDef s_command;
    HAL_StatusTypeDef status;

    // /* Initialize the read command */
    s_command.InstructionMode = QSPI_INSTRUCTION_1_LINE;
    s_command.Instruction = get_specialized_instruction(QUAD_OUT_FAST_READ_CMD, offset);
    s_command.AddressMode = QSPI_ADDRESS_1_LINE;
    s_command.AddressSize = get_address_size(offset);
    s_command.AlternateByteMode = QSPI_ALTERNATE_BYTES_NONE;
    s_command.DataMode = QSPI_DATA_4_LINES;
    s_command.DummyCycles = N25QXXA_DUMMY_CYCLES_READ_QUAD;
    s_command.DdrMode = QSPI_DDR_MODE_DISABLE;
    s_command.DdrHoldHalfCycle = QSPI_DDR_HHC_ANALOG_DELAY;
    s_command.SIOOMode = QSPI_SIOO_INST_EVERY_CMD;

    s_command.NbData = len;
    s_command.Address = offset;

    size_t retcode = len;

    mutex_acquire(&spiflash_mutex);
    // /* Configure the command */
    status = HAL_QSPI_Command(&qspi_handle, &s_command, HAL_QPSI_TIMEOUT_DEFAULT_VALUE);
    if (status != HAL_OK) {
        retcode =  hal_error_to_status(status);
        goto err;
    }

    // /* Reception of the data */
    status = qspi_rx_dma(&qspi_handle, &s_command, buf);
    if (status != HAL_OK) {
        retcode = hal_error_to_status(status);
        goto err;
    }

err:
    mutex_release(&spiflash_mutex);
    return retcode;
}

static ssize_t spiflash_bdev_read_block(struct bdev* device, void* buf,
                                        bnum_t block, uint count)
{
    count = bio_trim_block_range(device, block, count);
    if (count == 0)
        return 0;

    return spiflash_bdev_read(device, buf, block << device->block_shift,
                              count << device->block_shift);
}

static ssize_t spiflash_bdev_write_block(struct bdev* device, const void* _buf,
        bnum_t block, uint count)
{
    count = bio_trim_block_range(device, block, count);
    if (count == 0) {
        return 0;
    }

    const uint8_t *buf = _buf;

    mutex_acquire(&spiflash_mutex);

    ssize_t total_bytes_written = 0;
    for (; count > 0; count--, block++) {
        ssize_t bytes_written = qspi_write_page_unsafe(block * N25QXXA_PAGE_SIZE, buf);
        if (bytes_written < 0) {
            printf("qspi_write_page_unsafe failed\n");
            total_bytes_written = bytes_written;
            goto err;
        }

        buf += N25QXXA_PAGE_SIZE;
        total_bytes_written += bytes_written;
    }

err:
    mutex_release(&spiflash_mutex);
    return total_bytes_written;
}

static ssize_t spiflash_bdev_erase(struct bdev* device, off_t offset,
                                   size_t len)
{
    len = bio_trim_range(device, offset, len);
    if (len == 0) {
        return 0;
    }

    ssize_t total_erased = 0;

    mutex_acquire(&spiflash_mutex);

    // Choose an erase strategy based on the number of bytes being erased.
    if (len == device->total_size && offset == 0) {
        // Bulk erase the whole flash.
        total_erased = qspi_bulk_erase(device);
        goto finish;
    }

    // Erase as many sectors as necessary, then switch to subsector erase for
    // more fine grained erasure.
    while (((ssize_t)len - total_erased) >= N25QXXA_SECTOR_SIZE) {
        ssize_t erased = qspi_erase_sector(device, offset);
        if (erased < 0) {
            total_erased = erased;
            goto finish;
        }
        total_erased += erased;
        offset += erased;
    }

    while (total_erased < (ssize_t)len) {
        ssize_t erased = qspi_erase_subsector(device, offset);
        if (erased < 0) {
            total_erased = erased;
            goto finish;
        }
        total_erased += erased;
        offset += erased;
    }

finish:
    mutex_release(&spiflash_mutex);
    return total_erased;
}

static int spiflash_ioctl(struct bdev* device, int request, void* argp)
{
    int ret = ERR_NOT_SUPPORTED;

    switch (request) {
        case BIO_IOCTL_GET_MEM_MAP:
            /* put the device into linear mode */
            ret = qspi_enable_linear();
            if (ret != NO_ERROR)
                break;
            if (argp)
                *(void **)argp = (void*)QSPI_BASE;
            break;
    }

    return ret;
}

static ssize_t qspi_write_page_unsafe(uint32_t addr, const uint8_t *data)
{
    if (!IS_ALIGNED(addr, N25QXXA_PAGE_SIZE)) {
        return ERR_INVALID_ARGS;
    }

    HAL_StatusTypeDef status;

    QSPI_CommandTypeDef s_command = {
        .InstructionMode   = QSPI_INSTRUCTION_1_LINE,
        .Instruction       = get_specialized_instruction(QUAD_IN_FAST_PROG_CMD, addr),
        .AddressMode       = QSPI_ADDRESS_1_LINE,
        .AddressSize       = get_address_size(addr),
        .AlternateByteMode = QSPI_ALTERNATE_BYTES_NONE,
        .DataMode          = QSPI_DATA_4_LINES,
        .DummyCycles       = 0,
        .DdrMode           = QSPI_DDR_MODE_DISABLE,
        .DdrHoldHalfCycle  = QSPI_DDR_HHC_ANALOG_DELAY,
        .SIOOMode          = QSPI_SIOO_INST_EVERY_CMD,
        .Address           = addr,
        .NbData            = N25QXXA_PAGE_SIZE
    };

    status_t write_enable_result = qspi_write_enable_unsafe(&qspi_handle);
    if (write_enable_result != NO_ERROR) {
        return write_enable_result;
    }

    status = HAL_QSPI_Command(&qspi_handle, &s_command, HAL_QPSI_TIMEOUT_DEFAULT_VALUE);
    if (status != HAL_OK) {
        return hal_error_to_status(status);
    }

    status = qspi_tx_dma(&qspi_handle, &s_command, (uint8_t*)data);
    if (status != HAL_OK) {
        return hal_error_to_status(status);
    }

    status_t auto_polling_mem_ready_result =
        qspi_auto_polling_mem_ready_unsafe(&qspi_handle);
    if (auto_polling_mem_ready_result != NO_ERROR) {
        return auto_polling_mem_ready_result;
    }

    return N25QXXA_PAGE_SIZE;
}


status_t qspi_flash_init(size_t flash_size)
{
    status_t result = NO_ERROR;

    event_init(&cmd_event, false, EVENT_FLAG_AUTOUNSIGNAL);
    event_init(&tx_event, false, EVENT_FLAG_AUTOUNSIGNAL);
    event_init(&rx_event, false, EVENT_FLAG_AUTOUNSIGNAL);

    mutex_init(&spiflash_mutex);
    result = mutex_acquire(&spiflash_mutex);
    if (result != NO_ERROR) {
        return result;
    }

    qspi_handle.Instance = QUADSPI;

    HAL_StatusTypeDef status;

    // Enable the QuadSPI memory interface clock
    __HAL_RCC_QSPI_CLK_ENABLE();

    // Reset the QuadSPI memory interface
    __HAL_RCC_QSPI_FORCE_RESET();
    __HAL_RCC_QSPI_RELEASE_RESET();

    // Setup the QSPI Flash device.
    qspi_handle.Init.ClockPrescaler = 1;
    qspi_handle.Init.FifoThreshold = 4;
    qspi_handle.Init.SampleShifting = QSPI_SAMPLE_SHIFTING_HALFCYCLE;
    qspi_handle.Init.FlashSize = POSITION_VAL(flash_size) - 1;
    qspi_handle.Init.ChipSelectHighTime = QSPI_CS_HIGH_TIME_2_CYCLE;
    qspi_handle.Init.ClockMode = QSPI_CLOCK_MODE_0;
    qspi_handle.Init.FlashID = QSPI_FLASH_ID_1;
    qspi_handle.Init.DualFlash = QSPI_DUALFLASH_DISABLE;

    status = HAL_QSPI_Init(&qspi_handle);
    if (status != HAL_OK) {
        result = hal_error_to_status(status);
        goto err;
    }

    // enable the qspi interrupt
    HAL_NVIC_EnableIRQ(QUADSPI_IRQn);

    result = qspi_reset_memory_unsafe(&qspi_handle);
    if (result != NO_ERROR) {
        goto err;
    }

    result = qspi_dummy_cycles_cfg_unsafe(&qspi_handle);
    if (result != NO_ERROR) {
        goto err;
    }

    result = qspi_dma_init(&qspi_handle);
    if (result != NO_ERROR) {
        goto err;
    }

    // Initialize the QSPI Flash and register it as a Block I/O device.
    geometry.erase_size = log2_uint(N25QXXA_SUBSECTOR_SIZE);
    geometry.erase_shift = log2_uint(N25QXXA_SUBSECTOR_SIZE);
    geometry.start = 0;
    geometry.size = flash_size;

    bio_initialize_bdev(&qspi_flash_device, device_name, N25QXXA_PAGE_SIZE,
                        (flash_size / N25QXXA_PAGE_SIZE), 1, &geometry);

    qspi_flash_device.read = &spiflash_bdev_read;
    qspi_flash_device.read_block = &spiflash_bdev_read_block;
    // qspi_flash_device.write has a default hook that will be okay
    qspi_flash_device.write_block = &spiflash_bdev_write_block;
    qspi_flash_device.erase = &spiflash_bdev_erase;
    qspi_flash_device.ioctl = &spiflash_ioctl;

    /* we erase to 0xff */
    qspi_flash_device.erase_byte = 0xff;

    bio_register_device(&qspi_flash_device);

err:
    mutex_release(&spiflash_mutex);
    return result;
}

status_t hal_error_to_status(HAL_StatusTypeDef hal_status)
{
    switch (hal_status) {
        case HAL_OK:
            return NO_ERROR;
        case HAL_ERROR:
            return ERR_GENERIC;
        case HAL_BUSY:
            return ERR_BUSY;
        case HAL_TIMEOUT:
            return ERR_TIMED_OUT;
        default:
            return ERR_GENERIC;
    }
}

static ssize_t qspi_erase(bdev_t *device, uint32_t block_addr, uint32_t instruction)
{
    if (instruction == BULK_ERASE_CMD && block_addr != 0) {
        // This call was probably not what the user intended since the
        // block_addr is irrelevant when performing a bulk erase.
        return ERR_INVALID_ARGS;
    }

    QSPI_CommandTypeDef erase_cmd;

    ssize_t num_erased_bytes;
    switch (instruction) {
        case SUBSECTOR_ERASE_CMD: {
            num_erased_bytes = N25QXXA_SUBSECTOR_SIZE;
            erase_cmd.AddressSize = get_address_size(block_addr);
            erase_cmd.Instruction = get_specialized_instruction(instruction, block_addr);
            erase_cmd.AddressMode = QSPI_ADDRESS_1_LINE;
            erase_cmd.Address     = block_addr;

            break;
        }
        case SECTOR_ERASE_CMD: {
            num_erased_bytes = N25QXXA_SECTOR_SIZE;
            erase_cmd.AddressSize = get_address_size(block_addr);
            erase_cmd.Instruction = get_specialized_instruction(instruction, block_addr);
            erase_cmd.AddressMode = QSPI_ADDRESS_1_LINE;
            erase_cmd.Address     = block_addr;

            break;
        }
        case BULK_ERASE_CMD: {
            num_erased_bytes = device->total_size;
            erase_cmd.AddressMode = QSPI_ADDRESS_NONE;
            erase_cmd.Instruction = instruction;
            break;
        }
        default: {
            // Instruction must be a valid erase instruction.
            return ERR_INVALID_ARGS;
        }
    }

    erase_cmd.InstructionMode   = QSPI_INSTRUCTION_1_LINE;
    erase_cmd.AlternateByteMode = QSPI_ALTERNATE_BYTES_NONE;
    erase_cmd.DataMode          = QSPI_DATA_NONE;
    erase_cmd.DummyCycles       = 0;
    erase_cmd.DdrMode           = QSPI_DDR_MODE_DISABLE;
    erase_cmd.DdrHoldHalfCycle  = QSPI_DDR_HHC_ANALOG_DELAY;
    erase_cmd.SIOOMode          = QSPI_SIOO_INST_EVERY_CMD;


    /* Enable write operations */
    status_t qspi_write_enable_result = qspi_write_enable_unsafe(&qspi_handle);
    if (qspi_write_enable_result != NO_ERROR) {
        return qspi_write_enable_result;
    }

    /* Send the command */
    if (qspi_cmd(&qspi_handle, &erase_cmd) != HAL_OK) {
        return ERR_GENERIC;
    }

    /* Configure automatic polling mode to wait for end of erase */
    status_t auto_polling_mem_ready_result =
        qspi_auto_polling_mem_ready_unsafe(&qspi_handle);
    if (auto_polling_mem_ready_result != NO_ERROR) {
        return auto_polling_mem_ready_result;
    }

    return num_erased_bytes;
}

static ssize_t qspi_bulk_erase(bdev_t *device)
{
    return qspi_erase(device, 0, BULK_ERASE_CMD);
}

static ssize_t qspi_erase_sector(bdev_t *device, uint32_t block_addr)
{
    return qspi_erase(device, block_addr, SECTOR_ERASE_CMD);
}

static ssize_t qspi_erase_subsector(bdev_t *device, uint32_t block_addr)
{
    return qspi_erase(device, block_addr, SUBSECTOR_ERASE_CMD);
}

static HAL_StatusTypeDef qspi_cmd(QSPI_HandleTypeDef* qspi_handle,
                                  QSPI_CommandTypeDef* s_command)
{
    HAL_StatusTypeDef result = HAL_QSPI_Command_IT(qspi_handle, s_command);
    event_wait(&cmd_event);
    return result;
}

// Send data and wait for interrupt.
static HAL_StatusTypeDef qspi_tx_dma(QSPI_HandleTypeDef* qspi_handle, QSPI_CommandTypeDef* s_command, uint8_t* buf)
{
    // Make sure cache is flushed to RAM before invoking the DMA controller.
    arch_clean_invalidate_cache_range((addr_t)buf, s_command->NbData);

    HAL_StatusTypeDef result = HAL_QSPI_Transmit_DMA(qspi_handle, buf);
    event_wait(&tx_event);

    // CPU may have cached data while we were performing the DMA.
    arch_invalidate_cache_range((addr_t)buf, s_command->NbData);

    return result;
}

// Send data and wait for interrupt.
static HAL_StatusTypeDef qspi_rx_dma(QSPI_HandleTypeDef* qspi_handle, QSPI_CommandTypeDef* s_command, uint8_t* buf)
{
    // DMA controller is about to overwrite this memory. All data pointing to it
    // is invalid.
    arch_invalidate_cache_range((addr_t)buf, s_command->NbData);

    HAL_StatusTypeDef result = HAL_QSPI_Receive_DMA(qspi_handle, buf);
    event_wait(&rx_event);

    // DMA controller has modified this memory. Any caches that reference it are
    // now invalid.
    arch_invalidate_cache_range((addr_t)buf, s_command->NbData);

    return result;
}

void stm32_QUADSPI_IRQ(void)
{
    arm_cm_irq_entry();
    HAL_QSPI_IRQHandler(&qspi_handle);
    arm_cm_irq_exit(true);
}

void stm32_DMA2_Stream7_IRQ(void)
{
    arm_cm_irq_entry();
    HAL_DMA_IRQHandler(&hdma);
    arm_cm_irq_exit(true);
}

/* IRQ Context */
void HAL_QSPI_CmdCpltCallback(QSPI_HandleTypeDef *hqspi)
{
    event_signal(&cmd_event, false);
}

/* IRQ Context */
void HAL_QSPI_RxCpltCallback(QSPI_HandleTypeDef *hqspi)
{
    event_signal(&rx_event, false);
}

/* IRQ Context */
void HAL_QSPI_TxCpltCallback(QSPI_HandleTypeDef *hqspi)
{
    event_signal(&tx_event, false);
}

status_t qspi_dma_init(QSPI_HandleTypeDef *hqspi)
{
    /* QSPI DMA Controller Clock */
    __HAL_RCC_DMA2_CLK_ENABLE();

    hdma.Init.Channel             = DMA_CHANNEL_3;
    hdma.Init.PeriphInc           = DMA_PINC_DISABLE;
    hdma.Init.MemInc              = DMA_MINC_ENABLE;
    hdma.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;
    hdma.Init.MemDataAlignment    = DMA_MDATAALIGN_BYTE;
    hdma.Init.Mode                = DMA_NORMAL;
    hdma.Init.Priority            = DMA_PRIORITY_LOW;
    hdma.Init.FIFOMode            = DMA_FIFOMODE_DISABLE;
    hdma.Init.FIFOThreshold       = DMA_FIFO_THRESHOLD_FULL;
    hdma.Init.MemBurst            = DMA_MBURST_SINGLE;
    hdma.Init.PeriphBurst         = DMA_PBURST_SINGLE;
    hdma.Instance                 = DMA2_Stream7;

    __HAL_LINKDMA(hqspi, hdma, hdma);
    HAL_StatusTypeDef hal_result = HAL_DMA_Init(&hdma);
    if (hal_result != HAL_OK) {
        return hal_error_to_status(hal_result);
    }

    HAL_NVIC_EnableIRQ(DMA2_Stream7_IRQn);

    return NO_ERROR;
}

static uint32_t get_address_size(uint32_t address)
{
    if (address >= FOUR_BYTE_ADDR_THRESHOLD) {
        return QSPI_ADDRESS_32_BITS;
    }
    return QSPI_ADDRESS_24_BITS;
}

// Converts a 3 byte instruction into a 4 byte instruction if necessary.
static uint32_t get_specialized_instruction(uint32_t instruction, uint32_t address)
{
    if (address < FOUR_BYTE_ADDR_THRESHOLD) {
        return instruction;
    }

    switch (instruction) {
        case READ_CMD:
            return READ_4_BYTE_ADDR_CMD;
        case FAST_READ_CMD:
            return FAST_READ_4_BYTE_ADDR_CMD;
        case DUAL_OUT_FAST_READ_CMD:
            return DUAL_OUT_FAST_READ_4_BYTE_ADDR_CMD;
        case DUAL_INOUT_FAST_READ_CMD:
            return DUAL_INOUT_FAST_READ_4_BYTE_ADDR_CMD;
        case QUAD_OUT_FAST_READ_CMD:
            return QUAD_OUT_FAST_READ_4_BYTE_ADDR_CMD;
        case QUAD_INOUT_FAST_READ_CMD:
            return QUAD_INOUT_FAST_READ_4_BYTE_ADDR_CMD;
        case PAGE_PROG_CMD:
            return PAGE_PROG_4_BYTE_ADDR_CMD;
        case QUAD_IN_FAST_PROG_CMD:
            return QUAD_IN_FAST_PROG_4_BYTE_ADDR_CMD;
        case SUBSECTOR_ERASE_CMD:
            return SUBSECTOR_ERASE_4_BYTE_ADDR_CMD;
        case SECTOR_ERASE_CMD:
            return SECTOR_ERASE_4_BYTE_ADDR_CMD;
    }

    return instruction;
}

status_t qspi_enable_linear(void)
{
    status_t result = NO_ERROR;

    mutex_acquire(&spiflash_mutex);

    result = qspi_dummy_cycles_cfg_unsafe(&qspi_handle);

    QSPI_CommandTypeDef s_command = {
        .InstructionMode   = QSPI_INSTRUCTION_1_LINE,
        .AddressSize       = QSPI_ADDRESS_24_BITS,
        .AlternateByteMode = QSPI_ALTERNATE_BYTES_NONE,
        .DdrMode           = QSPI_DDR_MODE_DISABLE,
        .DdrHoldHalfCycle  = QSPI_DDR_HHC_ANALOG_DELAY,
        .AddressMode       = QSPI_ADDRESS_1_LINE,
        .Instruction       = QUAD_OUT_FAST_READ_CMD,
        .DataMode          = QSPI_DATA_4_LINES,
        .DummyCycles       = 10,
        .SIOOMode          = QSPI_SIOO_INST_EVERY_CMD
    };

    QSPI_MemoryMappedTypeDef linear_mode_cfg = {
        .TimeOutActivation = QSPI_TIMEOUT_COUNTER_DISABLE,
    };

    HAL_StatusTypeDef hal_result = HAL_QSPI_MemoryMapped(&qspi_handle, &s_command, &linear_mode_cfg);
    if (hal_result != HAL_OK) {
        result = hal_error_to_status(hal_result);
        goto err;
    }

err:
    mutex_release(&spiflash_mutex);
    return result;
}