Training courses

Kernel and Embedded Linux

Bootlin training courses

Embedded Linux, kernel,
Yocto Project, Buildroot, real-time,
graphics, boot time, debugging...

Bootlin logo

Elixir Cross Referencer

  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
/*	$NetBSD: e32boot.cpp,v 1.1 2013/04/28 12:11:27 kiyohara Exp $	*/
/*
 * Copyright (c) 2012, 2013 KIYOHARA Takashi
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <e32base.h>
#include <e32def.h>
#include <e32std.h>

#include "cpu.h"
#include "e32boot.h"
#include "ekern.h"
#include "epoc32.h"
#include "netbsd.h"


class E32BootLDD : public DLogicalDevice {
public:
	E32BootLDD(void);
	virtual TInt Install(void);
	virtual void GetCaps(TDes8 &) const;
	virtual DLogicalChannel *CreateL(void);
};

class E32BootChannel : public DLogicalChannel {
public:
	E32BootChannel(DLogicalDevice *);

protected:
	virtual void DoCancel(TInt);
	virtual void DoRequest(TInt, TAny *, TAny *);
	virtual TInt DoControl(TInt, TAny *, TAny *);

private:
	EPOC32 *epoc32;
	TAny *safeAddress;

	TInt BootNetBSD(NetBSD *, struct btinfo_common *);
};


/* E32Dll() function is required by all DLLs. */
GLDEF_C TInt
E32Dll(TDllReason)
{

	return KErrNone;
}

EXPORT_C DLogicalDevice *
CreateLogicalDevice(void)
{

	return new E32BootLDD;
}

E32BootLDD::E32BootLDD(void)
{
	/* Nothing */
}

TInt
E32BootLDD::Install(void)
{

	return SetName(&E32BootName);
}

void
E32BootLDD::GetCaps(TDes8 &aDes) const
{
	TVersion version(0, 0, 0);	/* XXXXX: What is it? Don't check? */

	aDes.FillZ(aDes.MaxLength());
	aDes.Copy((TUint8 *)&version, Min(aDes.MaxLength(), sizeof(version)));
}

DLogicalChannel *
E32BootLDD::CreateL(void)
{

	return new (ELeave) E32BootChannel(this);
}


E32BootChannel::E32BootChannel(DLogicalDevice *aDevice)
    : DLogicalChannel(aDevice)
{

	epoc32 = new EPOC32;
	safeAddress = NULL;
}

void
E32BootChannel::DoCancel(TInt aReqNo)
{
	/* Nothing */
}

void
E32BootChannel::DoRequest(TInt aReqNo, TAny *a1, TAny *a2)
{
	/* Nothing */
}

TInt
E32BootChannel::DoControl(TInt aFunction, TAny *a1, TAny *a2)
{

	switch (aFunction) {
	case KE32BootGetProcessorID:
	{
		TInt id;

		__asm("mrc	p15, 0, %0, c0, c0" : "=r"(id));
		*(TUint *)a1 = id;
		break;
	}

	case KE32BootSetSafeAddress:
	{
		safeAddress = (TAny *)PAGE_ALIGN(a1);
		break;
	}

	case KE32BootBootNetBSD:
	{
		NetBSD *netbsd = (NetBSD *)a1;
		struct btinfo_common *bootinfo = (struct btinfo_common *)a2;

		BootNetBSD(netbsd, bootinfo);

		/* NOTREACHED */

		break;
	}

	default:
		break;
	}
	return KErrNone;
}

TInt
E32BootChannel::BootNetBSD(NetBSD *netbsd, struct btinfo_common *bootinfo)
{
	TAny *mmu_disabled, *ttb;

	__asm("adr %0, mmu_disabled" : "=r"(mmu_disabled));
	mmu_disabled = epoc32->GetPhysicalAddress(mmu_disabled);
	/*
	 * ARMv3 can't read TTB from CP15 C1.
	 * Also can't read Control Register.
	 */
	ttb = epoc32->GetPhysicalAddress(epoc32->GetTTB());

	__asm __volatile("				\
	mrs	r12, cpsr;				\
	/* Clear PSR_MODE and Interrupts */		\
	bic	r12, r12, #0xdf;			\
	/* Disable Interrupts(IRQ/FIQ) */		\
	orr	r12, r12, #(3 << 6);			\
	/* Set SVC32 MODE */				\
	orr	r12, r12, #0x13;			\
	msr	cpsr_c, r12;				\
							\
	ldr	r10, [%0, #0x0];			\
	ldr	sp, [%0, #0x4];				\
	ldr	lr, [%0, #0x8];				\
	mov	r12, %1;				\
	" :: "r"(netbsd), "r"(bootinfo));

	__asm __volatile("				\
	mov	r7, %2;					\
	mov	r8, %1;					\
	mov	r9, %0;					\
							\
	/* Set all domains to 15 */			\
	mov	r0, #0xffffffff;			\
	mcr	p15, 0, r0, c3, c0;			\
							\
	/* Disable MMU */				\
	mov	r0, #0x38; /* WBUF | 32BP | 32BD */	\
	mcr	p15, 0, r0, c1, c0, 0;			\
							\
	mov	pc, r7;					\
							\
mmu_disabled:						\
	/*						\
	 * r8	safe address(maybe frame-buffer address)\
	 * r9	ttb					\
	 * r10	buffer (netbsd)				\
	 * r11	memory descriptor			\
	 * r12	bootinfo				\
	 * sp	load descriptor				\
	 * lr	entry point				\
	 */						\
	/* save lr to r7 before call functions. */	\
	mov	r7, lr;					\
							\
	mov	r0, r8;					\
	mov	r1, r9;					\
	bl	vtop;					\
	mov	r8, r0;					\
							\
	/*						\
	 * Copy bootinfo to safe address.		\
	 * That addr used to framebuffer by EPOC32.	\
	 */						\
	mov	r0, r12;				\
	mov	r1, r9;					\
	bl	vtop;					\
	mov	r1, r0;					\
	mov	r12, r8;				\
	mov	r0, r8;					\
	mov	r2, #0x400;				\
	bl	copy;					\
							\
	/* save lr(r7) to r8. it is no need. */		\
	mov	r8, r7;					\
							\
	/* Copy loader to safe address + 0x400. */	\
	add	r0, r12, #0x400;			\
	adr	r1, miniloader_start;			\
	adr	r2, miniloader_end;			\
	sub	r2, r2, r1;				\
	bl	copy;					\
							\
	/* Make load-descriptor to safe addr + 0x800. */\
	mov	r0, sp;					\
	mov	r1, r9;					\
	bl	vtop;					\
	mov	sp, r0;					\
	add	r4, r12, #0x800;			\
							\
next_section:						\
	ldmia	sp!, {r5 - r7};				\
							\
next_page:						\
	add	r0, r10, r6;				\
	mov	r1, r9;					\
	bl	vtop;					\
	/* vtop returns set mask to r2 */		\
	orr	r2, r0, r2;				\
	add	r2, r2, #1;				\
	sub	r2, r2,	r0;				\
	cmp	r2, r7;					\
	movgt	r2, r7;					\
	mov	r1, r0;					\
	mov	r0, r5;					\
	stmia	r4!, {r0 - r2};				\
	add	r5, r5, r2;				\
	add	r6, r6, r2;				\
	subs	r7, r7, r2;				\
	bgt	next_page;				\
							\
	ldr	r0, [sp];				\
	cmp	r0, #0xffffffff;			\
	beq	fin;					\
	/* Pad to section align. */			\
	str	r5, [r4], #4;				\
	mov	r6, #0xffffffff;			\
	str	r6, [r4], #4;				\
	sub	r2, r0, r5;				\
	str	r2, [r4], #4;				\
	b	next_section;				\
							\
fin:							\
	stmia	r4, {r5 - r7};				\
	add	sp, r12, #0x800;			\
							\
	/* save lr(r8) to r11. r11 is no need. */	\
	mov	r11, r8;				\
							\
	/* Fixup load-descriptor by BTINFO_MEMORY. */	\
	mov	r10, r12;				\
	mov	r9, sp;					\
	add	r8, sp, #12;				\
next_bootinfo:						\
	ldmia	r10, {r0, r1};				\
	cmp	r1, #0;		/* BTINFO_NONE */	\
	beq	btinfo_none;				\
							\
	cmp	r1, #2;		/* BTINFO_MEMORY */	\
	beq	btinfo_memory;				\
	add	r10, r10, r0;				\
	b	next_bootinfo;				\
							\
btinfo_none:						\
	/* ENOMEM */					\
	add	r2, r12, #0x800;			\
	mov	r1, #640;				\
	mov	r0, #0x00ff0000;			\
	orr	r0, r0, #0x00ff;			\
98:							\
	str	r0, [r2], #4;				\
	subs	r1, r1, #4;				\
	bgt	98b;					\
	mov	r1, #640;				\
	mov	r0, #0xff000000;			\
	orr	r0, r0, #0xff00;			\
99:							\
	str	r0, [r2], #4;				\
	subs	r1, r1, #4;				\
	bgt	99b;					\
100:							\
	b	100b;					\
							\
btinfo_memory:						\
	ldmia	r10!, {r4 - r7};			\
	ldr	r4, [r9, #0];				\
	subs	r4, r4, r6;				\
	addgt	r6, r6, r4;				\
	subgt	r7, r7, r4;				\
next_desc:						\
	ldmia	r9, {r3 - r5};				\
	ldmia	r8!, {r0 - r2};				\
	add	r3, r3, r5;				\
	add	r4, r4, r5;				\
	cmp	r3, r0;					\
	cmpeq	r4, r1;					\
	beq	join_desc;				\
							\
	ldr	r3, [r9, #0];				\
	cmp	r3, r6;					\
	strlt	r6, [r9, #0];	/* Fixup */		\
	cmp	r5, r7;					\
	bgt	split_desc;				\
	add	r6, r6, r5;				\
	sub	r7, r7, r5;				\
	add	r9, r9, #12;				\
	stmia	r9, {r0 - r2};				\
	cmp	r0, #0xffffffff;			\
	beq	fixuped;				\
	b	next_desc;				\
							\
join_desc:	/* Join r8 descriptor to r9. */		\
	add	r5, r5, r2;				\
	str	r5, [r9, #8];				\
	b	next_desc;				\
							\
split_desc:	/* Split r9 descriptor. */		\
	ldr	r3, [r9, #0];				\
	ldr	r4, [r9, #4];				\
	str	r7, [r9, #8];				\
							\
	sub	r6, r5, r7;				\
	add	r5, r4, r7;				\
	add	r4, r3, r7;				\
	sub	r8, r8, #12;	/* Back to prev desc */	\
	add	r9, r9, #12;/* Point to splited desc */ \
							\
	cmp	r8, r9;					\
	bne	2f;					\
	add	r0, r8, #12;				\
	mov	r1, r8;					\
	mov	r2, #0;					\
1:							\
	ldr	r3, [r8, r2];				\
	add	r2, r2, #12;				\
	cmp	r3, #0xffffffff;			\
	bne	1b;					\
	bl	copy;					\
	add	r8, r8, #12; /* Point to moved desc */	\
2:							\
	stmia	r9, {r4 - r6};				\
	b	next_bootinfo;				\
							\
fixuped:						\
	/* Jump to miniloader. Our LR is entry-point! */\
	add	pc, r12, #0x400;			\
							\
vtop:							\
	/*						\
	 * paddr vtop(vaddr, ttb)			\
	 */						\
	bic	r2, r0, #0x000f0000; /* L1_ADDR_BITS */	\
	bic	r2, r2, #0x0000ff00; /* L1_ADDR_BITS */	\
	bic	r2, r2, #0x000000ff; /* L1_ADDR_BITS */	\
	mov	r2, r2, lsr #(20 - 2);			\
	ldr	r1, [r1, r2];				\
	and	r3, r1, #0x3;	/* L1_TYPE_MASK */	\
	cmp	r3, #0;					\
	bne	valid;					\
							\
invalid:						\
	mov	r0, #-1;				\
	mov	pc, lr;					\
							\
valid:							\
	cmp	r3, #0x2;				\
	bgt	3f;					\
	beq	2f;					\
							\
1:	/* Coarse L2 */					\
	mov	r2, #10;				\
	b	l2;					\
							\
2:	/* Section */					\
	mov	r2, #0xff000000;    /* L1_S_ADDR_MASK */\
	add	r2, r2, #0x00f00000;/* L1_S_ADDR_MASK */\
	mvn	r2, r2;					\
	bic	r3, r1, r2;				\
	and	r0, r0, r2;				\
	orr	r0, r3, r0;				\
	mov	pc, lr;					\
							\
3:	/* Fine L2 */					\
	mov	r2, #12;				\
l2:							\
	mov	r3, #1;					\
	mov	r3, r3, lsl r2;				\
	sub	r3, r3, #1;				\
	bic	r1, r1, r3;	/* L2 table */		\
	mov	r3, r0, lsl #12;			\
	mov	r3, r3, lsr #12;			\
	sub	r2, r2, #22;				\
	rsb	r2, r2, #0;				\
	mov	r3, r3, lsr r2;	/* index for L2 */	\
	ldr	r1, [r1, r3, lsl #2];			\
	and	r3, r1, #0x3;	/* L2_TYPE_MASK */	\
	cmp	r3, #0;					\
	beq	invalid;				\
	cmp	r3, #2;					\
	movlt	r2, #16;	/* L2_L_SHIFT */	\
	moveq	r2, #12;	/* L2_S_SHIFT */	\
	movgt	r2, #10;	/* L2_T_SHIFT */	\
	mov	r3, #1;					\
	mov	r2, r3, lsl r2;				\
	sub	r2, r2, #1;				\
	bic	r3, r1, r2;				\
	and	r0, r0, r2;				\
	orr	r0, r3, r0;				\
	mov	pc, lr;					\
							\
miniloader_start:					\
	b	miniloader;				\
							\
copy:							\
	/*						\
	 * void copy(dest, src, len)			\
	 */						\
	cmp	r0, r1;					\
	bgt	rcopy;					\
lcopy:							\
	ldr	r3, [r1], #4;				\
	str	r3, [r0], #4;				\
	subs	r2, r2, #4;				\
	bgt	lcopy;					\
	mov	pc, lr;					\
rcopy:							\
	subs	r2, r2, #4;				\
	ldr	r3, [r1, r2];				\
	str	r3, [r0, r2];				\
	bgt	rcopy;					\
	mov	pc, lr;					\
							\
							\
miniloader:						\
	/*						\
	 * r11	entry-point				\
	 * r12	bootinfo				\
	 * sp	load-descriptor				\
	 */						\
load:							\
	ldmia	sp!, {r0 - r2};				\
	cmp	r0, #0xffffffff;			\
	beq	end;					\
	cmp	r1, #0xffffffff;/* Skip section align */\
	blne	copy;		 /* or copy */		\
	b	load;					\
							\
end:							\
	mov	r0, r12;				\
	mov	pc, r11;				\
	nop;						\
	nop;						\
miniloader_end:						\
							\
	"
	::"r"(ttb),
	  "r"(safeAddress),
	  "r"(mmu_disabled)
	);

	/* NOTREACHED */

	return -1;
}