pinebuds/platform/main/startup_main.S
2022-08-15 17:20:27 +08:00

196 lines
4.9 KiB
ArmAsm

/***************************************************************************
*
* Copyright 2015-2019 BES.
* All rights reserved. All unpublished rights reserved.
*
* No part of this work may be used or reproduced in any form or by any
* means, or stored in a database or retrieval system, without prior written
* permission of BES.
*
* Use of this work is governed by a license granted by BES.
* This work contains confidential and proprietary information of
* BES. which is protected by copyright, trade secret,
* trademark and other intellectual property rights.
*
****************************************************************************/
#ifndef __ARM_ARCH_ISA_ARM
#if defined(NOSTD) || defined(__ARMCC_VERSION)
#define __STARTUP_CLEAR_BSS
#endif
#ifdef __ARMCC_VERSION
#include "link_sym_armclang.h"
#endif
.syntax unified
.section .boot_loader, "ax", %progbits
.thumb
.thumb_func
.align 2
.globl Boot_Loader
.type Boot_Loader, %function
Boot_Loader:
#ifdef __ARM_ARCH_8M_MAIN__
ldr r0, =__StackLimit
msr msplim, r0
#endif
#if defined(CHIP_BEST2001) && defined(LARGE_RAM)
ldr r3, =0x4000008c
ldr r0, [r3]
bic.w r0, r0, #0x03f80000
orr.w r0, r0, #0x00f80000 /*0x1f<<19*/
str r0, [r3]
#endif
ldr r3, =__StackTop
msr msp, r3
bl NVIC_InitVectors
#ifndef __NO_BOOT_INIT
bl BootInit
#endif
#ifdef USER_SECURE_BOOT
bl user_secure_boot_init
#endif
/* Firstly it copies data from read only memory to RAM. There are two schemes
* to copy. One can copy more than one sections. Another can only copy
* one section. The former scheme needs more instructions and read-only
* data to implement than the latter.
* Macro __STARTUP_COPY_MULTIPLE is used to choose between two schemes. */
#ifdef __STARTUP_COPY_MULTIPLE
/* Multiple sections scheme.
*
* Between symbol address __copy_table_start__ and __copy_table_end__,
* there are array of triplets, each of which specify:
* offset 0: LMA of start of a section to copy from
* offset 4: VMA of start of a section to copy to
* offset 8: size of the section to copy. Must be multiply of 4
*
* All addresses must be aligned to 4 bytes boundary.
*/
ldr r4, =__copy_table_start__
ldr r5, =__copy_table_end__
.L_loop0:
cmp r4, r5
bge .L_loop0_done
ldr r1, [r4]
ldr r2, [r4, #4]
ldr r3, [r4, #8]
.L_loop0_0:
subs r3, #4
ittt ge
ldrge r0, [r1, r3]
strge r0, [r2, r3]
bge .L_loop0_0
adds r4, #12
b .L_loop0
.L_loop0_done:
#else
/* Single section scheme.
*
* The ranges of copy from/to are specified by following symbols
* __etext: LMA of start of the section to copy from. Usually end of text
* __data_start__: VMA of start of the section to copy to
* __data_end__: VMA of end of the section to copy to
*
* All addresses must be aligned to 4 bytes boundary.
*/
ldr r1, =__etext
ldr r2, =__data_start__
ldr r3, =__data_end__
.L_loop1:
cmp r2, r3
ittt lt
ldrlt r0, [r1], #4
strlt r0, [r2], #4
blt .L_loop1
#endif /*__STARTUP_COPY_MULTIPLE */
/* This part of work usually is done in C library startup code. Otherwise,
* define this macro to enable it in this startup.
*
* There are two schemes too. One can clear multiple BSS sections. Another
* can only clear one section. The former is more size expensive than the
* latter.
*
* Define macro __STARTUP_CLEAR_BSS_MULTIPLE to choose the former.
* Otherwise efine macro __STARTUP_CLEAR_BSS to choose the later.
*/
#ifdef __STARTUP_CLEAR_BSS_MULTIPLE
/* Multiple sections scheme.
*
* Between symbol address __copy_table_start__ and __copy_table_end__,
* there are array of tuples specifying:
* offset 0: Start of a BSS section
* offset 4: Size of this BSS section. Must be multiply of 4
*/
ldr r3, =__zero_table_start__
ldr r4, =__zero_table_end__
.L_loop2:
cmp r3, r4
bge .L_loop2_done
ldr r1, [r3]
ldr r2, [r3, #4]
movs r0, 0
.L_loop2_0:
subs r2, #4
itt ge
strge r0, [r1, r2]
bge .L_loop2_0
adds r3, #8
b .L_loop2
.L_loop2_done:
#elif defined (__STARTUP_CLEAR_BSS)
/* Single BSS section scheme.
*
* The BSS section is specified by following symbols
* __bss_start__: start of the BSS section.
* __bss_end__: end of the BSS section.
*
* Both addresses must be aligned to 4 bytes boundary.
*/
ldr r1, =__bss_start__
ldr r2, =__bss_end__
movs r0, 0
.L_loop3:
cmp r1, r2
itt lt
strlt r0, [r1], #4
blt .L_loop3
#endif /* __STARTUP_CLEAR_BSS_MULTIPLE || __STARTUP_CLEAR_BSS */
#ifndef __NO_SYSTEM_INIT
bl SystemInit
#endif
#if defined(__ARMCC_VERSION) && !defined(NOSTD)
bl __rt_entry
#else
bl _start
#endif
.pool
.size Boot_Loader, . - Boot_Loader
.end
#endif