aboutsummaryrefslogtreecommitdiff
path: root/machine/fdt.c
blob: 4f72f7370c8c7ac07b24703c6c172f73982ae1a9 (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
#include <stdint.h>
#include <string.h>
#include "fdt.h"
#include "mtrap.h"

static inline uint32_t bswap(uint32_t x)
{
  uint32_t y = (x & 0x00FF00FF) <<  8 | (x & 0xFF00FF00) >>  8;
  uint32_t z = (y & 0x0000FFFF) << 16 | (y & 0xFFFF0000) >> 16;
  return z;
}

static uint32_t *fdt_scan_helper(
  uint32_t *lex,
  const char *strings,
  struct fdt_scan_node *node,
  const struct fdt_cb *cb)
{
  struct fdt_scan_node child;
  struct fdt_scan_prop prop;
  int last = 0;

  child.parent = node;
  // these are the default cell counts, as per the FDT spec
  child.address_cells = 2;
  child.size_cells = 1;
  prop.node = node;

  while (1) {
    switch (bswap(lex[0])) {
      case FDT_NOP: {
        lex += 1;
        break;
      }
      case FDT_PROP: {
        assert (!last);
        prop.name  = strings + bswap(lex[2]);
        prop.len   = bswap(lex[1]);
        prop.value = lex + 3;
        if (node && !strcmp(prop.name, "#address-cells")) { node->address_cells = bswap(lex[3]); }
        if (node && !strcmp(prop.name, "#size-cells"))    { node->size_cells    = bswap(lex[3]); }
        lex += 3 + (prop.len+3)/4;
        cb->prop(&prop, cb->extra);
        break;
      }
      case FDT_BEGIN_NODE: {
        uint32_t *lex_next;
        if (!last && node && cb->done) cb->done(node, cb->extra);
        last = 1;
        child.name = (const char *)(lex+1);
        if (cb->open) cb->open(&child, cb->extra);
        lex_next = fdt_scan_helper(
          lex + 2 + strlen(child.name)/4,
          strings, &child, cb);
        if (cb->close && cb->close(&child, cb->extra) == -1)
          while (lex != lex_next) *lex++ = bswap(FDT_NOP);
        lex = lex_next;
        break;
      }
      case FDT_END_NODE: {
        if (!last && node && cb->done) cb->done(node, cb->extra);
        return lex + 1;
      }
      default: { // FDT_END
        if (!last && node && cb->done) cb->done(node, cb->extra);
        return lex;
      }
    }
  }
}

void fdt_scan(uintptr_t fdt, const struct fdt_cb *cb)
{
  struct fdt_header *header = (struct fdt_header *)fdt;

  // Only process FDT that we understand
  if (bswap(header->magic) != FDT_MAGIC ||
      bswap(header->last_comp_version) > FDT_VERSION) return;

  const char *strings = (const char *)(fdt + bswap(header->off_dt_strings));
  uint32_t *lex = (uint32_t *)(fdt + bswap(header->off_dt_struct));

  fdt_scan_helper(lex, strings, 0, cb);
}

uint32_t fdt_size(uintptr_t fdt)
{
  struct fdt_header *header = (struct fdt_header *)fdt;

  // Only process FDT that we understand
  if (bswap(header->magic) != FDT_MAGIC ||
      bswap(header->last_comp_version) > FDT_VERSION) return 0;
  return bswap(header->totalsize);
}

const uint32_t *fdt_get_address(const struct fdt_scan_node *node, const uint32_t *value, uint64_t *result)
{
  *result = 0;
  for (int cells = node->address_cells; cells > 0; --cells)
    *result = (*result << 32) + bswap(*value++);
  return value;
}

const uint32_t *fdt_get_size(const struct fdt_scan_node *node, const uint32_t *value, uint64_t *result)
{
  *result = 0;
  for (int cells = node->size_cells; cells > 0; --cells)
    *result = (*result << 32) + bswap(*value++);
  return value;
}

int fdt_string_list_index(const struct fdt_scan_prop *prop, const char *str)
{
  const char *list = (const char *)prop->value;
  const char *end = list + prop->len;
  int index = 0;
  while (end - list > 0) {
    if (!strcmp(list, str)) return index;
    ++index;
    list += strlen(list) + 1;
  }
  return -1;
}

//////////////////////////////////////////// MEMORY SCAN /////////////////////////////////////////

struct mem_scan {
  int memory;
  const uint32_t *reg_value;
  int reg_len;
};

static void mem_open(const struct fdt_scan_node *node, void *extra)
{
  struct mem_scan *scan = (struct mem_scan *)extra;
  memset(scan, 0, sizeof(*scan));
}

static void mem_prop(const struct fdt_scan_prop *prop, void *extra)
{
  struct mem_scan *scan = (struct mem_scan *)extra;
  if (!strcmp(prop->name, "device_type") && !strcmp((const char*)prop->value, "memory")) {
    scan->memory = 1;
  } else if (!strcmp(prop->name, "reg")) {
    scan->reg_value = prop->value;
    scan->reg_len = prop->len;
  }
}

static void mem_done(const struct fdt_scan_node *node, void *extra)
{
  struct mem_scan *scan = (struct mem_scan *)extra;
  const uint32_t *value = scan->reg_value;
  const uint32_t *end = value + scan->reg_len/4;
  uintptr_t self = (uintptr_t)mem_done;

  if (!scan->memory) return;
  assert (scan->reg_value && scan->reg_len % 4 == 0);

  while (end - value > 0) {
    uint64_t base, size;
    value = fdt_get_address(node->parent, value, &base);
    value = fdt_get_size   (node->parent, value, &size);
    if (base <= self && self <= base + size) { mem_size = size; }
  }
  assert (end == value);
}

void query_mem(uintptr_t fdt)
{
  struct fdt_cb cb;
  struct mem_scan scan;

  memset(&cb, 0, sizeof(cb));
  cb.open = mem_open;
  cb.prop = mem_prop;
  cb.done = mem_done;
  cb.extra = &scan;

  mem_size = 0;
  fdt_scan(fdt, &cb);
  assert (mem_size > 0);
}

///////////////////////////////////////////// HART SCAN //////////////////////////////////////////

static uint32_t hart_phandles[MAX_HARTS];
uint64_t hart_mask;

struct hart_scan {
  const struct fdt_scan_node *cpu;
  int hart;
  const struct fdt_scan_node *controller;
  int cells;
  uint32_t phandle;
};

static void hart_open(const struct fdt_scan_node *node, void *extra)
{
  struct hart_scan *scan = (struct hart_scan *)extra;
  if (!scan->cpu) {
    scan->hart = -1;
  }
  if (!scan->controller) {
    scan->cells = 0;
    scan->phandle = 0;
  }
}

static void hart_prop(const struct fdt_scan_prop *prop, void *extra)
{
  struct hart_scan *scan = (struct hart_scan *)extra;
  if (!strcmp(prop->name, "device_type") && !strcmp((const char*)prop->value, "cpu")) {
    assert (!scan->cpu);
    scan->cpu = prop->node;
  } else if (!strcmp(prop->name, "interrupt-controller")) {
    assert (!scan->controller);
    scan->controller = prop->node;
  } else if (!strcmp(prop->name, "#interrupt-cells")) {
    scan->cells = bswap(prop->value[0]);
  } else if (!strcmp(prop->name, "phandle")) {
    scan->phandle = bswap(prop->value[0]);
  } else if (!strcmp(prop->name, "reg")) {
    uint64_t reg;
    fdt_get_address(prop->node->parent, prop->value, &reg);
    scan->hart = reg;
  }
}

static void hart_done(const struct fdt_scan_node *node, void *extra)
{
  struct hart_scan *scan = (struct hart_scan *)extra;

  if (scan->cpu == node) {
    assert (scan->hart >= 0);
  }

  if (scan->controller == node && scan->cpu) {
    assert (scan->phandle > 0);
    assert (scan->cells == 1);

    if (scan->hart < MAX_HARTS) {
      hart_phandles[scan->hart] = scan->phandle;
      hart_mask |= 1 << scan->hart;
      hls_init(scan->hart);
    }
  }
}

static int hart_close(const struct fdt_scan_node *node, void *extra)
{
  struct hart_scan *scan = (struct hart_scan *)extra;
  if (scan->cpu == node) scan->cpu = 0;
  if (scan->controller == node) scan->controller = 0;
  return 0;
}

void query_harts(uintptr_t fdt)
{
  struct fdt_cb cb;
  struct hart_scan scan;

  memset(&cb, 0, sizeof(cb));
  memset(&scan, 0, sizeof(scan));
  cb.open = hart_open;
  cb.prop = hart_prop;
  cb.done = hart_done;
  cb.close= hart_close;
  cb.extra = &scan;

  fdt_scan(fdt, &cb);

  // The current hart should have been detected
  assert ((hart_mask >> read_csr(mhartid)) != 0);
}

///////////////////////////////////////////// CLINT SCAN /////////////////////////////////////////

struct clint_scan
{
  int compat;
  uint64_t reg;
  const uint32_t *int_value;
  int int_len;
  int done;
};

static void clint_open(const struct fdt_scan_node *node, void *extra)
{
  struct clint_scan *scan = (struct clint_scan *)extra;
  scan->compat = 0;
  scan->reg = 0;
  scan->int_value = 0;
}

static void clint_prop(const struct fdt_scan_prop *prop, void *extra)
{
  struct clint_scan *scan = (struct clint_scan *)extra;
  if (!strcmp(prop->name, "compatible") && fdt_string_list_index(prop, "riscv,clint0") >= 0) {
    scan->compat = 1;
  } else if (!strcmp(prop->name, "reg")) {
    fdt_get_address(prop->node->parent, prop->value, &scan->reg);
  } else if (!strcmp(prop->name, "interrupts-extended")) {
    scan->int_value = prop->value;
    scan->int_len = prop->len;
  }
}

static void clint_done(const struct fdt_scan_node *node, void *extra)
{
  struct clint_scan *scan = (struct clint_scan *)extra;
  const uint32_t *value = scan->int_value;
  const uint32_t *end = value + scan->int_len/4;

  if (!scan->compat) return;
  assert (scan->reg != 0);
  assert (scan->int_value && scan->int_len % 16 == 0);
  assert (!scan->done); // only one clint

  scan->done = 1;
  mtime = (void*)((uintptr_t)scan->reg + 0xbff8);

  for (int index = 0; end - value > 0; ++index) {
    uint32_t phandle = bswap(value[0]);
    int hart;
    for (hart = 0; hart < MAX_HARTS; ++hart)
      if (hart_phandles[hart] == phandle)
        break;
    if (hart < MAX_HARTS) {
      hls_t *hls = OTHER_HLS(hart);
      hls->ipi = (void*)((uintptr_t)scan->reg + index * 4);
      hls->timecmp = (void*)((uintptr_t)scan->reg + 0x4000 + (index * 8));
    }
    value += 4;
  }
}

void query_clint(uintptr_t fdt)
{
  struct fdt_cb cb;
  struct clint_scan scan;

  memset(&cb, 0, sizeof(cb));
  cb.open = clint_open;
  cb.prop = clint_prop;
  cb.done = clint_done;
  cb.extra = &scan;

  scan.done = 0;
  fdt_scan(fdt, &cb);
  assert (scan.done);
}

///////////////////////////////////////////// PLIC SCAN /////////////////////////////////////////

struct plic_scan
{
  int compat;
  uint64_t reg;
  uint32_t *int_value;
  int int_len;
  int done;
  int ndev;
};

static void plic_open(const struct fdt_scan_node *node, void *extra)
{
  struct plic_scan *scan = (struct plic_scan *)extra;
  scan->compat = 0;
  scan->reg = 0;
  scan->int_value = 0;
}

static void plic_prop(const struct fdt_scan_prop *prop, void *extra)
{
  struct plic_scan *scan = (struct plic_scan *)extra;
  if (!strcmp(prop->name, "compatible") && fdt_string_list_index(prop, "riscv,plic0") >= 0) {
    scan->compat = 1;
  } else if (!strcmp(prop->name, "reg")) {
    fdt_get_address(prop->node->parent, prop->value, &scan->reg);
  } else if (!strcmp(prop->name, "interrupts-extended")) {
    scan->int_value = prop->value;
    scan->int_len = prop->len;
  } else if (!strcmp(prop->name, "riscv,ndev")) {
    scan->ndev = bswap(prop->value[0]);
  }
}

#define HART_BASE	0x200000
#define HART_SIZE	0x1000
#define ENABLE_BASE	0x2000
#define ENABLE_SIZE	0x80

static void plic_done(const struct fdt_scan_node *node, void *extra)
{
  struct plic_scan *scan = (struct plic_scan *)extra;
  const uint32_t *value = scan->int_value;
  const uint32_t *end = value + scan->int_len/4;

  if (!scan->compat) return;
  assert (scan->reg != 0);
  assert (scan->int_value && scan->int_len % 8 == 0);
  assert (scan->ndev >= 0 && scan->ndev < 1024);
  assert (!scan->done); // only one plic

  scan->done = 1;
  plic_priorities = (uint32_t*)(uintptr_t)scan->reg;
  plic_ndevs = scan->ndev;

  for (int index = 0; end - value > 0; ++index) {
    uint32_t phandle = bswap(value[0]);
    uint32_t cpu_int = bswap(value[1]);
    int hart;
    for (hart = 0; hart < MAX_HARTS; ++hart)
      if (hart_phandles[hart] == phandle)
        break;
    if (hart < MAX_HARTS) {
      hls_t *hls = OTHER_HLS(hart);
      if (cpu_int == IRQ_M_EXT) {
        hls->plic_m_ie     = (uintptr_t*)((uintptr_t)scan->reg + ENABLE_BASE + ENABLE_SIZE * index);
        hls->plic_m_thresh = (uint32_t*) ((uintptr_t)scan->reg + HART_BASE   + HART_SIZE   * index);
      } else if (cpu_int == IRQ_S_EXT) {
        hls->plic_s_ie     = (uintptr_t*)((uintptr_t)scan->reg + ENABLE_BASE + ENABLE_SIZE * index);
        hls->plic_s_thresh = (uint32_t*) ((uintptr_t)scan->reg + HART_BASE   + HART_SIZE   * index);
      } else {
        printm("PLIC wired hart %d to wrong interrupt %d", hart, cpu_int);
      }
    }
    value += 2;
  }
#if 0
  printm("PLIC: prio %x devs %d\r\n", (uint32_t)(uintptr_t)plic_priorities, plic_ndevs);
  for (int i = 0; i < MAX_HARTS; ++i) {
    hls_t *hls = OTHER_HLS(i);
    printm("CPU %d: %x %x %x %x\r\n", i, (uint32_t)(uintptr_t)hls->plic_m_ie, (uint32_t)(uintptr_t)hls->plic_m_thresh, (uint32_t)(uintptr_t)hls->plic_s_ie, (uint32_t)(uintptr_t)hls->plic_s_thresh);
  }
#endif
}

void query_plic(uintptr_t fdt)
{
  struct fdt_cb cb;
  struct plic_scan scan;

  memset(&cb, 0, sizeof(cb));
  cb.open = plic_open;
  cb.prop = plic_prop;
  cb.done = plic_done;
  cb.extra = &scan;

  scan.done = 0;
  fdt_scan(fdt, &cb);
}

static void plic_redact(const struct fdt_scan_node *node, void *extra)
{
  struct plic_scan *scan = (struct plic_scan *)extra;
  uint32_t *value = scan->int_value;
  uint32_t *end = value + scan->int_len/4;

  if (!scan->compat) return;
  scan->done = 1;

  while (end - value > 0) {
    if (bswap(value[1]) == IRQ_M_EXT) value[1] = bswap(-1);
    value += 2;
  }
}

void filter_plic(uintptr_t fdt)
{
  struct fdt_cb cb;
  struct plic_scan scan;

  memset(&cb, 0, sizeof(cb));
  cb.open = plic_open;
  cb.prop = plic_prop;
  cb.done = plic_redact;
  cb.extra = &scan;

  scan.done = 0;
  fdt_scan(fdt, &cb);
}

//////////////////////////////////////////// COMPAT SCAN ////////////////////////////////////////

struct compat_scan
{
  const char *compat;
  int depth;
  int kill;
};

static void compat_open(const struct fdt_scan_node *node, void *extra)
{
  struct compat_scan *scan = (struct compat_scan *)extra;
  ++scan->depth;
}

static void compat_prop(const struct fdt_scan_prop *prop, void *extra)
{
  struct compat_scan *scan = (struct compat_scan *)extra;
  if (!strcmp(prop->name, "compatible") && fdt_string_list_index(prop, scan->compat) >= 0)
    if (scan->depth < scan->kill)
      scan->kill = scan->depth;
}

static int compat_close(const struct fdt_scan_node *node, void *extra)
{
  struct compat_scan *scan = (struct compat_scan *)extra;
  if (scan->kill == scan->depth--) {
    scan->kill = 999;
    return -1;
  } else {
    return 0;
  }
}

void filter_compat(uintptr_t fdt, const char *compat)
{
  struct fdt_cb cb;
  struct compat_scan scan;

  memset(&cb, 0, sizeof(cb));
  cb.open = compat_open;
  cb.prop = compat_prop;
  cb.close = compat_close;
  cb.extra = &scan;

  scan.compat = compat;
  scan.depth = 0;
  scan.kill = 999;
  fdt_scan(fdt, &cb);
}

//////////////////////////////////////////// HART FILTER ////////////////////////////////////////

struct hart_filter {
  int compat;
  int hart;
  char *status;
  unsigned long mask;
};

static void hart_filter_open(const struct fdt_scan_node *node, void *extra)
{
  struct hart_filter *filter = (struct hart_filter *)extra;
  filter->status = 0;
  filter->compat = 0;
  filter->hart = -1;
}

static void hart_filter_prop(const struct fdt_scan_prop *prop, void *extra)
{
  struct hart_filter *filter = (struct hart_filter *)extra;
  if (!strcmp(prop->name, "device_type") && !strcmp((const char*)prop->value, "cpu")) {
    filter->compat = 1;
  } else if (!strcmp(prop->name, "reg")) {
    uint64_t reg;
    fdt_get_address(prop->node->parent, prop->value, &reg);
    filter->hart = reg;
  } else if (!strcmp(prop->name, "status")) {
    filter->status = (char*)prop->value;
  }
}

static void hart_filter_done(const struct fdt_scan_node *node, void *extra)
{
  struct hart_filter *filter = (struct hart_filter *)extra;

  if (!filter->compat) return;
  assert (filter->status);
  assert (filter->hart >= 0);

  if (((filter->mask >> filter->hart) & 1) && !strcmp(filter->status, "okay")) {
    strcpy(filter->status, "masked");
    uint32_t *len = (uint32_t*)filter->status;
    len[-2] = bswap(strlen("masked")+1);
  }
}

void filter_harts(uintptr_t fdt, unsigned long hart_mask)
{
  struct fdt_cb cb;
  struct hart_filter filter;

  memset(&cb, 0, sizeof(cb));
  cb.open = hart_filter_open;
  cb.prop = hart_filter_prop;
  cb.done = hart_filter_done;
  cb.extra = &filter;

  filter.mask = hart_mask;
  fdt_scan(fdt, &cb);
}