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
/*	$NetBSD: imx7_machdep.c,v 1.11 2019/07/16 14:41:46 skrll Exp $	*/

/*-
 * Copyright (c) 2012 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Matt Thomas of 3am Software Foundry.
 *
 * 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 NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``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 FOUNDATION OR CONTRIBUTORS
 * 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 <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: imx7_machdep.c,v 1.11 2019/07/16 14:41:46 skrll Exp $");

#include "opt_evbarm_boardtype.h"
#include "opt_arm_debug.h"
#include "opt_console.h"
#include "opt_kgdb.h"
#include "com.h"
#include "opt_machdep.h"
#include "opt_imxuart.h"
#include "imxuart.h"
#include "opt_imx.h"

#include <sys/param.h>
#include <sys/bus.h>
#include <sys/atomic.h>
#include <sys/device.h>
#include <sys/kernel.h>
#include <sys/msgbuf.h>
#include <sys/reboot.h>
#include <sys/termios.h>

#include <dev/cons.h>

#include <uvm/uvm_extern.h>

#include <arm/db_machdep.h>
#include <arm/arm32/machdep.h>

#include <machine/autoconf.h>
#include <machine/bootconfig.h>

#include <arm/imx/imx7var.h>
#include <arm/imx/imx7_srcreg.h>
#include <arm/imx/imxuartvar.h>
#include <arm/imx/imxuartreg.h>

#include <evbarm/imx7/platform.h>

#ifdef VERBOSE_INIT_ARM
#define VPRINTF(...)	printf(__VA_ARGS__)
#else
#define VPRINTF(...)	__nothing
#endif

extern int _end[];
extern int KERNEL_BASE_phys[];
extern int KERNEL_BASE_virt[];

BootConfig bootconfig;
static char bootargs[MAX_BOOT_STRING];
char *boot_args = NULL;

/* filled in before cleaning bss. keep in .data */
u_int uboot_args[4] __attribute__((__section__(".data")));

#ifndef CONADDR
#define CONADDR	(IMX7_AIPS_BASE + AIPS3_UART1_BASE)
#endif
#ifndef CONSPEED
#define CONSPEED B115200
#endif
#ifndef CONMODE
#define CONMODE ((TTYDEF_CFLAG & ~(CSIZE | CSTOPB | PARENB)) | CS8) /* 8N1 */
#endif

void imx7_setup_iomux(void);
void imx7_setup_gpio(void);
void imx7board_device_register(device_t, void *);
void imx7_mpstart(void);
void imx7_platform_early_putchar(char);

#ifdef KGDB
#include <sys/kgdb.h>
#endif

static void
earlyconsputc(dev_t dev, int c)
{
	uartputc(c);
}

static int
earlyconsgetc(dev_t dev)
{
	return 0;
}

static struct consdev earlycons = {
	.cn_putc = earlyconsputc,
	.cn_getc = earlyconsgetc,
	.cn_pollc = nullcnpollc,
};

/*
 * Static device mappings. These peripheral registers are mapped at
 * fixed virtual addresses very early in initarm() so that we can use
 * them while booting the kernel, and stay at the same address
 * throughout whole kernel's life time.
 *
 * We use this table twice; once with bootstrap page table, and once
 * with kernel's page table which we build up in initarm().
 *
 * Since we map these registers into the bootstrap page table using
 * pmap_devmap_bootstrap() which calls pmap_map_chunk(), we map
 * registers segment-aligned and segment-rounded in order to avoid
 * using the 2nd page tables.
 */
static const struct pmap_devmap devmap[] = {
	{
		KERNEL_IO_IOREG_VBASE,
		IMX7_IOREG_PBASE,
		IMX7_IOREG_SIZE,
		VM_PROT_READ | VM_PROT_WRITE,
		PTE_NOCACHE,
	},
	{
		KERNEL_IO_ARMCORE_VBASE,
		IMX7_ARMCORE_PBASE,
		IMX7_ARMCORE_SIZE,
		VM_PROT_READ | VM_PROT_WRITE,
		PTE_NOCACHE,
	},
	{ 0, 0, 0, 0, 0 }
};

#ifdef PMAP_NEED_ALLOC_POOLPAGE
static struct boot_physmem bp_highgig = {
	.bp_start = IMX7_MEM_BASE / NBPG,
	.bp_pages = (KERNEL_VM_BASE - KERNEL_BASE) / NBPG,
	.bp_freelist = VM_FREELIST_ISADMA,
	.bp_flags = 0,
};
#endif

void
imx7_platform_early_putchar(char c)
{
#define CONADDR_VA (CONADDR - IMX7_IOREG_PBASE + KERNEL_IO_IOREG_VBASE)
	volatile uint32_t *uartaddr = cpu_earlydevice_va_p() ?
	    (volatile uint32_t *)CONADDR_VA :
	    (volatile uint32_t *)CONADDR;

	int timo = 150000;

	while ((uartaddr[IMX_USR2 / 4] & IMX_USR2_TXDC) == 0) {
		if (--timo == 0)
			break;
	}

	uartaddr[IMX_UTXD / 4] = c;

	timo = 150000;
	while ((uartaddr[IMX_USR2 / 4] & IMX_USR2_TXDC) == 0) {
		if (--timo == 0)
			break;
	}
}

void
imx7_mpstart(void)
{
#if defined(MULTIPROCESSOR)
	if (arm_cpu_max <= 1)
		return;

	const bus_space_tag_t bst = &armv7_generic_bs_tag;

	const bus_space_handle_t bsh = KERNEL_IO_IOREG_VBASE + AIPS1_SRC_BASE;
	const paddr_t mpstart = KERN_VTOPHYS((vaddr_t)cpu_mpstart);

	bus_space_write_4(bst, bsh, SRC_GPR3, mpstart);

	uint32_t rcr1 = bus_space_read_4(bst, bsh, SRC_A7RCR1);
	rcr1 |= SRC_A7RCR1_A7_CORE1_ENABLE;
	bus_space_write_4(bst, bsh, SRC_A7RCR1, rcr1);

	arm_dsb();
	__asm __volatile("sev" ::: "memory");

	for (int loop = 0; loop < 16; loop++) {
		VPRINTF("%u hatched %#x\n", loop, arm_cpu_hatched);
		if (arm_cpu_hatched == __BITS(arm_cpu_max - 1, 1))
			break;
		int timo = 1500000;
		while (arm_cpu_hatched != __BITS(arm_cpu_max - 1, 1))
			if (--timo == 0)
				break;
	}
	for (size_t i = 1; i < arm_cpu_max; i++) {
		if ((arm_cpu_hatched & __BIT(i)) == 0) {
		printf("%s: warning: cpu%zu failed to hatch\n",
			    __func__, i);
		}
	}

	VPRINTF(" (%u cpu%s, hatched %#x)",
	    arm_cpu_max, arm_cpu_max ? "s" : "",
	    arm_cpu_hatched);
#endif
}


/*
 * vaddr_t initarm(...)
 *
 * Initial entry point on startup. This gets called before main() is
 * entered.
 * It should be responsible for setting up everything that must be
 * in place when main is called.
 * This includes
 *   Taking a copy of the boot configuration structure.
 *   Initialising the physical console so characters can be printed.
 *   Setting up page tables for the kernel
 */
vaddr_t
initarm(void *arg)
{
	psize_t memsize;

	/*
	 * Heads up ... Setup the CPU / MMU / TLB functions
	 */
	if (set_cpufuncs())		// starts PMC counter
		panic("cpu not recognized!");

	cn_tab = &earlycons;

	extern char ARM_BOOTSTRAP_LxPT[];
	pmap_devmap_bootstrap((vaddr_t)ARM_BOOTSTRAP_LxPT, devmap);

	imx7_bootstrap(KERNEL_IO_IOREG_VBASE);

	imx7_setup_iomux();
	imx7_setup_gpio();

	consinit();

	cpu_domains((DOMAIN_CLIENT << (PMAP_DOMAIN_KERNEL*2)) | DOMAIN_CLIENT);

#ifdef NO_POWERSAVE
	cpu_do_powersave = 0;
#endif

	cortex_pmc_ccnt_init();

	printf("\nuboot arg = %#x, %#x, %#x, %#x\n",
	    uboot_args[0], uboot_args[1], uboot_args[2], uboot_args[3]);

	cpu_reset_address = imx7_reset;

	/* Talk to the user */
	printf("\nNetBSD/evbarm (" ___STRING(EVBARM_BOARDTYPE)
	    ", digprog=0x%08x) booting ...\n", imx7_chip_id());

#ifdef BOOT_ARGS
	char mi_bootargs[] = BOOT_ARGS;
	parse_mi_bootargs(mi_bootargs);
#endif /* BOOT_ARGS */
	bootargs[0] = '\0';

#ifdef VERBOSE_INIT_ARM
	printf("initarm: Configuring system");
#ifdef MULTIPROCESSOR
	printf(" (%u cpu%s, hatched %#x)",
	    arm_cpu_max, arm_cpu_max ? "s" : "",
	    arm_cpu_hatched);
#endif /* MULTIPROCESSOR */
	printf(", CLIDR=%010o CTR=%#x",
	    armreg_clidr_read(), armreg_ctr_read());
	printf("\n");
#endif /* VERBOSE_INIT_ARM */


#ifdef MEMSIZE
	memsize = MEMSIZE * 1024 * 1024;
#else
/*
 * Ugh... but this is better than proceeding using an uninitialized
 * value in memsize, as the code did before I added this branch...
 */
#error "MEMSIZE not set"
#endif

	bootconfig.dramblocks = 1;
#ifdef MEMSIZE_RESERVED
	/* reserved for Cortex-M4 core */
	memsize -= MEMSIZE_RESERVED * 1024 * 1024;
	bootconfig.dram[0].address = KERN_VTOPHYS(KERNEL_BASE) +
	    MEMSIZE_RESERVED * 1024 * 1024;
#else
	bootconfig.dram[0].address = KERN_VTOPHYS(KERNEL_BASE);
#endif
	bootconfig.dram[0].pages = memsize / PAGE_SIZE;

#ifdef __HAVE_MM_MD_DIRECT_MAPPED_PHYS
	const bool mapallmem_p = true;
#ifndef PMAP_NEED_ALLOC_POOLPAGE
	if (memsize > KERNEL_VM_BASE - KERNEL_BASE) {
		printf("%s: dropping RAM size from %luMB to %uMB\n",
		   __func__, (unsigned long) (memsize >> 20),
		   (KERNEL_VM_BASE - KERNEL_BASE) >> 20);
		memsize = KERNEL_VM_BASE - KERNEL_BASE;
	}
#endif
#else /* !__HAVE_MM_MD_DIRECT_MAPPED_PHYS */
	const bool mapallmem_p = false;
#endif /* __HAVE_MM_MD_DIRECT_MAPPED_PHYS */

	arm32_bootmem_init(bootconfig.dram[0].address,
	    memsize, (paddr_t)KERNEL_BASE_phys);
	arm32_kernel_vm_init(KERNEL_VM_BASE, ARM_VECTORS_LOW, 0, devmap,
	    mapallmem_p);

	/* we've a specific device_register routine */
	evbarm_device_register = imx7board_device_register;

#ifdef PMAP_NEED_ALLOC_POOLPAGE
	/*
	 * If we couldn't map all of memory via TTBR1, limit the memory the
	 * kernel can allocate from to be from the highest available 1GB.
	 */
	if (atop(memsize) > bp_highgig.bp_pages) {
		bp_highgig.bp_start += atop(memsize) - bp_highgig.bp_pages;
		arm_poolpage_vmfreelist = bp_highgig.bp_freelist;
		return initarm_common(KERNEL_VM_BASE, KERNEL_VM_SIZE,
		    &bp_highgig, 1);
	}
#endif
	vaddr_t sp = initarm_common(KERNEL_VM_BASE, KERNEL_VM_SIZE, NULL, 0);

	/*
	 * initarm_common flushes cache if required before AP start
	 */
	imx7_mpstart();

	return sp;
}

#ifdef CONSDEVNAME
const char consdevname[] = CONSDEVNAME;

#ifndef CONMODE
#define CONMODE	((TTYDEF_CFLAG & ~(CSIZE | CSTOPB | PARENB)) | CS8) /* 8N1 */
#endif
#ifndef CONSPEED
#define CONSPEED	115200
#endif

int consmode = CONMODE;
int consrate = CONSPEED;

#endif /* CONSDEVNAME */

#ifndef IMXUART_FREQ
#define IMXUART_FREQ	24000000
#endif

void
consinit(void)
{
	static int consinit_called = 0;

	if (consinit_called)
		return;

	consinit_called = 1;

#ifdef CONSDEVNAME
# if NIMXUART > 0
	imxuart_set_frequency(IMXUART_FREQ, 2);
# endif
# if (NIMXUART > 0) && defined(IMXUARTCONSOLE)
	if (strcmp(consdevname, CONSDEVNAME) == 0) {
		paddr_t consaddr;

		consaddr = CONADDR;
		imxuart_cnattach(&armv7_generic_bs_tag, consaddr, consrate, consmode);
		return;
	}
# endif /* (NIMXUART > 0) && defined(IMXUARTCONSOLE) */
#endif /* CONSDEVNAME */
}