111 lines
2.9 KiB
ArmAsm
111 lines
2.9 KiB
ArmAsm
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/*******************************************************************************
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*
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* Filename: arm_init.s
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*
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* Initialization for C-environment and basic operation. Adapted from
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* ATMEL cstartup.s.
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*
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* Revision information:
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*
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* 20AUG2004 kb_admin initial creation
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* 12JAN2005 kb_admin updated for 16KB eeprom
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* Atmel stack prevents loading full size at once
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*
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* BEGIN_KBDD_BLOCK
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* No warranty, expressed or implied, is included with this software. It is
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* provided "AS IS" and no warranty of any kind including statutory or aspects
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* relating to merchantability or fitness for any purpose is provided. All
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* intellectual property rights of others is maintained with the respective
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* owners. This software is not copyrighted and is intended for reference
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* only.
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* END_BLOCK
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*
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* $FreeBSD$
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******************************************************************************/
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.equ TWI_EEPROM_SIZE, 0x2000
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.equ ARM_MODE_USER, 0x10
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.equ ARM_MODE_FIQ, 0x11
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.equ ARM_MODE_IRQ, 0x12
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.equ ARM_MODE_SVC, 0x13
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.equ ARM_MODE_ABORT, 0x17
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.equ ARM_MODE_UNDEF, 0x1B
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.equ ARM_MODE_SYS, 0x1F
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.equ I_BIT, 0x80
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.equ F_BIT, 0x40
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.equ T_BIT, 0x20
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/*
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* Stack definitions
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*
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* Start near top of internal RAM.
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*/
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.equ END_INT_SRAM, 0x4000
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.equ SVC_STACK_START, (END_INT_SRAM - 0x4)
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.equ SVC_STACK_USE, 0x21800000
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start:
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/* vectors - must reside at address 0 */
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/* the format of this table is defined in the datasheet */
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B InitReset @; reset
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undefvec:
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B undefvec @; Undefined Instruction
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swivec:
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B swivec @; Software Interrupt
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pabtvec:
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B pabtvec @; Prefetch Abort
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dabtvec:
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B dabtvec @; Data Abort
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rsvdvec:
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.long (TWI_EEPROM_SIZE >> 9)
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irqvec:
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ldr pc, [pc,#-0xF20] @; IRQ : read the AIC
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fiqvec:
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B fiqvec @; FIQ
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InitReset:
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/* Set stack and init for SVC */
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ldr r1, = SVC_STACK_START
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mov sp, r1 @; Init stack SYS
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msr cpsr_c, #(ARM_MODE_SVC | I_BIT | F_BIT)
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mov sp, r1 @ ; Init stack SYS
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/* Perform system initialization */
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.extern _init
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bl _init
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ldr r1, = SVC_STACK_USE
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mov sp, r1 @ ; Move the stack to SDRAM
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/* Start execution at main */
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.extern main
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_main:
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__main:
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bl main
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/* main should not return. If it does, spin forever */
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infiniteLoop:
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b infiniteLoop
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/* the following section is used to store boot commands in */
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/* non-volatile memory. */
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.global BootCommandSection
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BootCommandSection:
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.string "Bootloader for KB9202 Evaluation Board."
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.string "c 0x20210000 0x10100000 0x80000 "
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.string "m 0 0 0 0 0 0 "
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.string "t 0x20000100 console=ttyS0,115200 root=/dev/ram rw initrd=0x20210000,654933"
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.string "e 0x10000000 "
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.string " "
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