更多相关文章：
《高通Qualcomm平台lk（light kernel）启动流程1——aboot_init()之前》：
http://blog.csdn.net/u014134180/article/details/78133916
《高通Qualcomm平台lk（light kernel）启动流程2——aboot_init()》：
http://blog.csdn.net/u014134180/article/details/78132580
《高通Qualcomm平台lk（light kernel）启动流程3——到高通lcm屏点亮》：
http://blog.csdn.net/u014134180/article/details/78177040
《[lcm] Qualcomm Android Display Subsystem 架构》
http://blog.csdn.net/u014134180/article/details/78129502
《[lcm] Qualcomm平台的显示屏lcd驱动移植步骤》：
http://blog.csdn.net/u014134180/article/details/78129499
《[lcm] Qualcomm平台兼容多显示屏lcd的方法&并从lk传输到kernel过程》:
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《[lcm] Qualcomm平台显示屏lcd添加I2C读取功能》：
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0、lk 启动总体流程
1、lk启动流程代码
lk/ arch/ arm/ crt0.S
/*
* Copyright (c) 2008 Travis Geiselbrecht
*
* Copyright (c) 2014, The Linux Foundation. All rights reserved.
*
* 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.
*/
#define DSB .byte 0x4f, 0xf0, 0x7f, 0xf5
#define ISB .byte 0x6f, 0xf0, 0x7f, 0xf5
.section ".text.boot"
.globl _start
_start:
b reset
b arm_undefined
b arm_syscall
b arm_prefetch_abort
b arm_data_abort
b arm_reserved
b arm_irq
b arm_fiq
reset:
#ifdef ENABLE_TRUSTZONE
/*Add reference to TZ symbol so linker includes it in final image */
ldr r7, =_binary_tzbsp_tzbsp_bin_start
#endif
/* do some cpu setup */
#if ARM_WITH_CP15
/* Read SCTLR */
mrc p15, 0, r0, c1, c0, 0
/* XXX this is currently for arm926, revist with armv6 cores */
/* new thumb behavior, low exception vectors, i/d cache disable, mmu disabled */
bic r0, r0, #(1<<15| 1<<13 | 1<<12)
bic r0, r0, #(1<<2 | 1<<0)
/* disable alignment faults */
bic r0, r0, #(1<<1)
/* Enable CP15 barriers by default */
#ifdef ARM_CORE_V8
orr r0, r0, #(1<<5)
#endif
/* Write SCTLR */
mcr p15, 0, r0, c1, c0, 0
#ifdef ENABLE_TRUSTZONE
/*nkazi: not needed ? Setting VBAR to location of new vector table : 0x80000 */
ldr r0, =0x00080000
mcr p15, 0, r0, c12, c0, 0
#endif
#endif
#if WITH_CPU_EARLY_INIT
/* call platform/arch/etc specific init code */
#ifndef ENABLE_TRUSTZONE
/* Not needed when TrustZone is the first bootloader that runs.*/
bl __cpu_early_init
#endif
/* declare return address as global to avoid using stack */
.globl _cpu_early_init_complete
_cpu_early_init_complete:
#endif
#if (!ENABLE_NANDWRITE)
#if WITH_CPU_WARM_BOOT
ldr r0, warm_boot_tag
cmp r0, #1
/* if set, warm boot */
ldreq pc, =BASE_ADDR
mov r0, #1
str r0, warm_boot_tag
#endif
#endif
/* see if we need to relocate */
mov r0, pc
sub r0, r0, #(.Laddr - _start)
.Laddr:
ldr r1, =_start
cmp r0, r1
beq .Lstack_setup
/* we need to relocate ourselves to the proper spot */
ldr r2, =__data_end
.Lrelocate_loop:
ldr r3, [r0], #4
str r3, [r1], #4
cmp r1, r2
bne .Lrelocate_loop
/* we're relocated, jump to the right address */
ldr r0, =.Lstack_setup
bx r0
.ltorg
#if WITH_CPU_WARM_BOOT
warm_boot_tag:
.word 0
#endif
.Lstack_setup:
/* set up the stack for irq, fiq, abort, undefined, system/user, and lastly supervisor mode */
mrs r0, cpsr
bic r0, r0, #0x1f
ldr r2, =abort_stack_top
orr r1, r0, #0x12 // irq
msr cpsr_c, r1
ldr r13, =irq_save_spot /* save a pointer to a temporary dumping spot used during irq delivery */
orr r1, r0, #0x11 // fiq
msr cpsr_c, r1
mov sp, r2
orr r1, r0, #0x17 // abort
msr cpsr_c, r1
mov sp, r2
orr r1, r0, #0x1b // undefined
msr cpsr_c, r1
mov sp, r2
orr r1, r0, #0x1f // system
msr cpsr_c, r1
mov sp, r2
orr r1, r0, #0x13 // supervisor
msr cpsr_c, r1
mov sp, r2
/* copy the initialized data segment out of rom if necessary */
ldr r0, =__data_start_rom
ldr r1, =__data_start
ldr r2, =__data_end
cmp r0, r1
beq .L__do_bss
.L__copy_loop:
cmp r1, r2
ldrlt r3, [r0], #4
strlt r3, [r1], #4
blt .L__copy_loop
.L__do_bss:
/* clear out the bss */
ldr r0, =__bss_start
ldr r1, =_end
mov r2, #0
.L__bss_loop:
cmp r0, r1
strlt r2, [r0], #4
blt .L__bss_loop
#ifdef ARM_CPU_CORTEX_A8
DSB
ISB
#endif
bl kmain
b .
.ltorg
.bss
.align 2
/* the abort stack is for unrecoverable errors.
* also note the initial working stack is set to here.
* when the threading system starts up it'll switch to a new
* dynamically allocated stack, so we don't need it for very long
*/
abort_stack:
.skip 1024
abort_stack_top:
lk/ kernel/ main.c
/*
* Copyright (c) 2008 Travis Geiselbrecht
*
* Copyright (c) 2009-2014, The Linux Foundation. All rights reserved.
*
* 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 <compiler.h>
#include <debug.h>
#include <string.h>
#include <app.h>
#include <arch.h>
#include <platform.h>
#include <target.h>
#include <lib/heap.h>
#include <kernel/thread.h>
#include <kernel/timer.h>
#include <kernel/dpc.h>
#include <boot_stats.h>
extern void *__ctor_list;
extern void *__ctor_end;
extern int __bss_start;
extern int _end;
static int bootstrap2(void *arg);
#if (ENABLE_NANDWRITE)
void bootstrap_nandwrite(void);
#endif
static void call_constructors(void)
{
void **ctor;
ctor = &__ctor_list;
while(ctor != &__ctor_end) {
void (*func)(void);
func = (void (*)())*ctor;
func();
ctor++;
}
}
/* called from crt0.S */
void kmain(void) __NO_RETURN __EXTERNALLY_VISIBLE;
void kmain(void)
{
thread_t *thr;
// get us into some sort of thread context
thread_init_early();
// early arch stuff
arch_early_init();
// do any super early platform initialization
platform_early_init();
// do any super early target initialization
target_early_init();
dprintf(INFO, "welcome to lk\n\n");
bs_set_timestamp(BS_BL_START);
// deal with any static constructors
dprintf(SPEW, "calling constructors\n");
call_constructors();
// bring up the kernel heap
dprintf(SPEW, "initializing heap\n");
heap_init();
__stack_chk_guard_setup();
// initialize the threading system
dprintf(SPEW, "initializing threads\n");
thread_init();
// initialize the dpc system
dprintf(SPEW, "initializing dpc\n");
dpc_init();
// initialize kernel timers
dprintf(SPEW, "initializing timers\n");
timer_init();
#if (!ENABLE_NANDWRITE)
// create a thread to complete system initialization
dprintf(SPEW, "creating bootstrap completion thread\n");
thr = thread_create("bootstrap2", &bootstrap2, NULL, DEFAULT_PRIORITY, DEFAULT_STACK_SIZE);
if (!thr)
{
panic("failed to create thread bootstrap2\n");
}
thread_resume(thr);
// enable interrupts
exit_critical_section();
// become the idle thread
thread_become_idle();
#else
bootstrap_nandwrite();
#endif
}
int main(void);
static int bootstrap2(void *arg)
{
dprintf(SPEW, "top of bootstrap2()\n");
arch_init();
// XXX put this somewhere else
#if WITH_LIB_BIO
bio_init();
#endif
#if WITH_LIB_FS
fs_init();
#endif
// initialize the rest of the platform
dprintf(SPEW, "initializing platform\n");
platform_init();
// initialize the target
dprintf(SPEW, "initializing target\n");
target_init();
dprintf(SPEW, "calling apps_init()\n");
apps_init();
return 0;
}
#if (ENABLE_NANDWRITE)
void bootstrap_nandwrite(void)
{
dprintf(SPEW, "top of bootstrap2()\n");
arch_init();
// initialize the rest of the platform
dprintf(SPEW, "initializing platform\n");
platform_init();
// initialize the target
dprintf(SPEW, "initializing target\n");
target_init();
dprintf(SPEW, "calling nandwrite_init()\n");
nandwrite_init();
return 0;
}
#endiflk/ app/ app.c
/*
* Copyright (c) 2009 Travis Geiselbrecht
*
* 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 <debug.h>
#include <app.h>
#include <kernel/thread.h>
extern const struct app_descriptor __apps_start;
extern const struct app_descriptor __apps_end;
static void start_app(const struct app_descriptor *app);
/* one time setup */
void apps_init(void)
{
const struct app_descriptor *app;
/* call all the init routines */
for (app = &__apps_start; app != &__apps_end; app++) {
if (app->init)
app->init(app);
}
/* start any that want to start on boot */
for (app = &__apps_start; app != &__apps_end; app++) {
if (app->entry && (app->flags & APP_FLAG_DONT_START_ON_BOOT) == 0) {
start_app(app);
}
}
}
static int app_thread_entry(void *arg)
{
const struct app_descriptor *app = (const struct app_descriptor *)arg;
app->entry(app, NULL);
return 0;
}
static void start_app(const struct app_descriptor *app)
{
thread_t *thr;
printf("starting app %s\n", app->name);
thr = thread_create(app->name, &app_thread_entry, (void *)app, DEFAULT_PRIORITY, DEFAULT_STACK_SIZE);
if(!thr)
{
return;
}
thread_resume(thr);
}
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《高通Qualcomm平台lk（light kernel）启动流程1——aboot_init()之前》： http://blog.csdn.net/u014134180/article/details/78133916
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