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Diffstat (limited to 'c/src/lib/libbsp/arm/gba/start/start.S')
| -rw-r--r-- | c/src/lib/libbsp/arm/gba/start/start.S | 396 |
1 files changed, 0 insertions, 396 deletions
diff --git a/c/src/lib/libbsp/arm/gba/start/start.S b/c/src/lib/libbsp/arm/gba/start/start.S deleted file mode 100644 index 99dfc9a034..0000000000 --- a/c/src/lib/libbsp/arm/gba/start/start.S +++ /dev/null @@ -1,396 +0,0 @@ -/** - * @file start.S - * - * RTEMS entry point. - */ -/* - * RTEMS GBA BSP - * - * Copyright (c) by Jeff Frohwein. - * - * Copyright (c) 2003, Jason Wilkins. - * - * Copyright (c) 2004 Markku Puro <markku.puro@kopteri.net> - * based on crt0.S v1.28 by Jeff Frohwein - * - * The license and distribution terms for this file may be - * found in the file LICENSE in this distribution or at - * http://www.rtems.org/license/LICENSE. - */ - -/***************************************************************************** - * This source file is based on work by Jeff Frohwein and Jason Wilkins - ***************************************************************************** - ***************************************************************************** - * crt0.S v1.28 by Jeff Frohwein - * : - * This file is released into the public domain for commercial - * or non-commercial usage with no restrictions placed upon it. - ***************************************************************************** - * Copyright 2003, Jason Wilkins. This source code is free for any use except - * that this copyright notice and the following disclaimers remain intact when - * the source is distributed. Object code and binary distributions may be made - * as if the code were in the public domain. - * - * THIS CODE WAS NOT MADE IN ASSOCIATION WITH NINTENDO AND DOES NOT MAKE USE - * OF ANY INTELLECTUAL PROPERTY CLAIMED BY NINTENDO. - * - * GAMEBOY ADVANCE IS A TRADEMARK OF NINTENDO. - * - * THIS CODE HAS BEEN PROVIDED "AS-IS" WITHOUT A WARRANTY OF ANY KIND, EITHER - * EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO IMPLIED WARRANTIES OF - * MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. THE ENTIRE RISK AS TO THE - * QUALITY OR PERFORMANCE OF THE CODE IS WITH YOU. - * - * IN NO EVENT, UNLESS AGREED TO IN WRITING, WILL ANY COPYRIGHT HOLDER, OR ANY - * OTHER PARTY, BE HELD LIABLE FOR ANY DAMAGES RESULTING FROM THE USE OR - * INABILITY TO USE THIS CODE. - *****************************************************************************/ - -#define __asm__ -#include <rtems/asm.h> -#include <asm_macros.h> -#include <arm_mode_bits.h> -/* @cond INCLUDE_ASM */ - -#ifndef NINTENDO_LOGO -#define NINTENDO_LOGO 1 -#endif - -#ifndef GBA_MULTIBOOT -#define GBA_MULTIBOOT 1 -#endif - -#ifndef GAME_TITLE -#define GAME_TITLE "RTEMS-RTOS " -#endif - -#ifdef GBA_MULTIBOOT - #ifndef GAME_CODE - #define GAME_CODE "MB " - #endif - #ifndef COMPLEMENT_CHECK - #define COMPLEMENT_CHECK 0xE2 - #endif -#else - #ifndef GAME_CODE - #define GAME_CODE "GBA " - #endif - #ifndef COMPLEMENT_CHECK - #define COMPLEMENT_CHECK 0xC7 - #endif -#endif - -#ifndef MAKER_CODE -#define MAKER_CODE "00" -#endif - -/** - * RTEMS entry point - * function void _start(void) - * - */ -/*****************************************************************************\ - ROM Header -\*****************************************************************************/ - -.text -.align -.arm - -/*---------------------------------------------------------------------------+ -| Nintendo Header: -| A special header is required or the GBA will refuse to run your code. -| -| File offsets from 0x0200000 or 0x08000000. -+----------------------------------------------------------------------------*/ - PUBLIC_ARM_FUNCTION(_start) - b SYM(_real_start) /* 0x00 Entry Point */ - SYM(_gba_rom_header): -#if NINTENDO_LOGO /* 0x04 Nintendo Logo Character Data */ -#include "logo.S" -#else - .fill 156, 1, 0 /* 0x04 Nintendo Logo Character Data */ -#endif - .ascii GAME_TITLE /* 0xA0 Game Title */ - .ascii GAME_CODE /* 0xAC Game Code */ - .ascii MAKER_CODE /* 0xB0 Maker Code */ - .byte 0x96 /* 0xB2 Fixed Value */ - .byte 0 /* 0xB3 Main Unit Code */ - .byte 0 /* 0xB4 Device Type */ - .byte 0, 0, 0, 0, 0, 0, 0 /* 0xB5 Reserved (7 Bytes) */ - .byte 0 /* 0xBC Software Version No. */ - .byte COMPLEMENT_CHECK /* 0xBD Complement Check */ - .byte 0, 0 /* 0xBE Reserved */ - .Lheader_end: - - -#if GBA_MULTIBOOT -/*---------------------------------------------------------------------------+ -| Multiboot Header: -| The following header is required if the code is meant for Multiboot. -| -| If the code has been downloaded through the serial port, then the GBA BIOS -| will set offset 0xC0 depending on the boot method: -| 1 = JoyBus, 3 = Multiboot -| It remains 0 for cartridges. -| -| offset 0xC4 will be set to the GBA's assigned slave number 1-3. -| This header also defines the symbols _boot_method and _slave_number for -| easy reference to these values. Some libraries may depend on them whether -| or not the code is meant for Multiboot. -| -+----------------------------------------------------------------------------*/ - SYM(_gba_multiboot_start): - b SYM(_real_start) /* 0xC0 Multiboot Entry Point */ - OBJECT(_boot_method) - .byte 0 /* 0xC4 Boot Method */ - OBJECT(_slave_number) - .byte 0 /* 0xC5 Slave Number (1-3) */ - .align - STATIC_OBJECT(_gba_mb_reserved) - .word 0, 0, 0, 0, 0, 0 /* 0xC8 Reserved (6 words) */ - SYM(_gba_joybus_start): - b SYM(_real_start) /* 0xE0 JoyBus Entry Point */ - .Lmultiboot_header_end: -#endif - -/*---------------------------------------------------------------------------+ -| Restore registers and stack from GBA bios IRQ frame and call ISR_Handler -+----------------------------------------------------------------------------*/ - EXTERN(_ISR_Handler) - .align - PUBLIC_ARM_FUNCTION(_gba_ISR_handler) - ldmfd r13!,{r0-r3,r12,r14} - b _ARMV4_Exception_interrupt - LABEL_END(_gba_ISR_handler) - - -/*---------------------------------------------------------------------------+ -| Code to initialize the low-level BSP environment -+----------------------------------------------------------------------------*/ - SYM(_real_start): - /* Initialize IRQ and USR Stack Pointers */ - SYM(_gba_init_stacks): - mov r0, #(Mode_IRQ | Int_Bits) /* No interrupts */ - msr cpsr, r0 /* switch to IRQ mode */ - ldr sp, =__sp_irq /* defined in linkcmds */ - mov r0, #(ModePriv | Int_Bits) /* No interrupts */ - msr cpsr, r0 /* switch to System Mode */ - ldr sp, =__sp_usr /* defined in linkcmds */ - - /* Switch to Thumb Mode */ - SYM(_gba_bx_thumb): - adr r0, .Lthumb + 1 - bx r0 - .thumb - .Lthumb: - /* Reduce gameboy waitstates */ - SYM(_reduce_waitstates): - ldr r1, =0x4000204 - ldrh r0, =0x4490 - strh r0, [r1] - - -#if GBA_MULTIBOOT -/*---------------------------------------------------------------------------+ -| Load Multiboot Image from ROM into RAM: -| Check to see if the image is meant for Multiboot or GamePak. If it is for -| Multiboot then check if it is currently running from EWRAM or from CARTROM. -| If it is running from CARTROM, then it needs to be copied to EWRAM and -| re-executed from the beginning. -| -| The reason for all this is to allow a program to be used "as-is" with a -| flash-cart, emulator, or MBV2-style Multiboot cable without rebuilding. -| -| NOTE: Any branchs used above this code need to be relative. -+----------------------------------------------------------------------------*/ - STATIC_THUMB_FUNCTION(_gba_load_multiboot) - ldr r0, =_start /* 8000000h=GamePak 2000000h=Multiboot*/ - ldr r1, =__gba_rom_start /* defined in linkcmds */ - cmp r0, r1 - beq SYM(_no_load_multiboot)/* skip if GamePak */ - mov r3, pc - cmp r1, r3 /* check program counter */ - bhi SYM(_no_load_multiboot)/* skip if already running from EWRAM */ - sub r3, r1, r0 /* diff between _start and CARTROM */ - ldr r2, =__load_stop_data /* defined in linkcmds */ - add r2, r2, r3 /* adjust pointer into ROM */ - bl SYM(gba_move_memory) - - /* patch multiboot header */ - ldr r0, =SYM(_boot_method) - mov r1, #3 - str r1, [r0] - - /* remember that multiboot image came from GamePak */ - ldr r0, =SYM(_gba_flash_loaded_multiboot) - mov r1, #0 - str r1, [r0] - - ldr r0, =SYM(_start) - bx r0 /* restart */ - LABEL_END(_gba_load_multiboot) - - .align 4 - OBJECT(_gba_flash_loaded_multiboot) - .word -1 - LABEL_END(_gba_flash_loaded_multiboot) - SYM(_no_load_multiboot): -#endif - -/* Initialize Standard Sections */ - STATIC_THUMB_FUNCTION(_gba_init_std_sections) - /* Copy internal work ram (iwram section ROM to RAM)*/ - ldr r0,=__iwram_start - ldr r1,=__load_start_iwram - ldr r2,=__load_stop_iwram - bl SYM(gba_move_memory) - - /* Copy external work ram (ewram section ROM to RAM) */ - ldr r0,=__ewram_start - ldr r1,=__load_start_ewram - ldr r2,=__load_stop_ewram - bl SYM(gba_move_memory) - - /* load initial values of variables like 'int foo = 42' */ - ldr r0, =__data_start /* defined in linkcmds */ - ldr r1, =__load_start_data /* defined in linkcmds */ - ldr r2, =__load_stop_data /* defined in linkcmds */ - bl SYM(gba_move_memory) - - /* zero the bss */ - ldr r0, =__bss_start /* defined in linkcmds */ - ldr r1, =__bss_end /* defined in linkcmds */ - bl SYM(gba_zero_memory) - LABEL_END(_gba_init_std_sections) - -/* Initialize Interrupt Vector */ - STATIC_THUMB_FUNCTION(_gba_init_intr_vect) - ldr r1, =__irq_vector /* defined in linkcmds */ - ldr r0, =SYM(_gba_ISR_handler) - str r0, [r1] - LABEL_END(_gba_init_intr_vect) - - -/* Enter the C code. If it returns, then restart */ - STATIC_THUMB_FUNCTION(_gba_call_arm_boot_card) - adr r1, .Larm - bx r1 - .arm - .Larm: - ldr r1, =boot_card - mov r0, #0 - bl SYM(_gba_call_via_r1) - - ldr r0, =SYM(_gba_reset) - SYM(_gba_call_via_r1): - bx r1 - -/* GBA Reset */ - PUBLIC_ARM_FUNCTION(_gba_reset) - adr r0, .Lthumb2 + 1 - bx r0 - .thumb - .Lthumb2: - /* disable interrupts */ - ldr r0, =0x04000208 - mov r1, #0 - strb r1, [r0] - - /* reset stack, default free area */ - ldr r0, =0x03007F00 - mov sp, r0 - -#if GBA_MULTIBOOT - ldr r0, =SYM(_gba_flash_loaded_multiboot) - ldr r0, [r0] - cmp r0, #0 - beq SYM(_reset) -#endif - - ldr r0, =_start /* defined in linkcmds */ - ldr r1, =__gba_rom_start /* defined in linkcmds */ - sub r0, r0, r1 - lsr r0, r0, #24 - - SYM(_reset): - /* soft reset (swi 0) parameter: where is _start */ - ldr r1, =0x03007FFA - strb r0, [r1] - mov r0, #0xFE /* clear all but EWRAM */ - swi 1 - swi 0 - LABEL_END(_gba_reset) - - -/*---------------------------------------------------------------------------+ -| Library Functions -+----------------------------------------------------------------------------*/ - -/* gba_zero_memory */ - PUBLIC_THUMB_FUNCTION(gba_zero_memory) - mov r2, #0 - nop - LABEL_END(gba_zero_memory) - -/* gba_set_memory */ - PUBLIC_THUMB_FUNCTION(gba_set_memory) - cmp r0, r1 - bcs .Lset_memory_return - - .Lset_memory_loop: - stmia r0!, {r2} - cmp r0, r1 - bcc .Lset_memory_loop - - .Lset_memory_return: - bx lr - LABEL_END(gba_set_memory) - -/* gba_move_memory */ - .align - PUBLIC_THUMB_FUNCTION(gba_move_memory) - cmp r0, r1 - bcc .Lforward_move /* if dst < src then forward copy */ - bhi .Lreverse_move /* if dst > src then reverse copy */ - bx lr /* else dst == src, nothing to do */ - - .Lforward_move: - cmp r1, r2 - bcs .Lmove_memory_return - - .Lforward_move_loop: - ldmia r1!, {r3} - stmia r0!, {r3} - cmp r1, r2 - bcc .Lforward_move_loop - bx lr - - .Lreverse_move: - cmp r2, r1 - bls .Lmove_memory_return - sub r3, r2, r1 - add r0, r0, r3 - - .Lreverse_move_loop: - sub r2, r2, #4 - ldr r3, [r2] - sub r0, r0, #4 - str r3, [r0] - cmp r2, r1 - bhi .Lreverse_move_loop - - .Lmove_memory_return: - bx lr - LABEL_END(gba_move_memory) - - -/* @todo FIXME: Remove unused handler needed by ../score/cpu_asm.S - *****************************************************************************/ - .arm - .global SWI_Handler -SWI_Handler: - mov pc, lr -/* @endcond */ - |