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Diffstat (limited to 'cpu/arm920t/start.S')
| -rw-r--r-- | cpu/arm920t/start.S | 436 |
1 files changed, 0 insertions, 436 deletions
diff --git a/cpu/arm920t/start.S b/cpu/arm920t/start.S deleted file mode 100644 index 779f192..0000000 --- a/cpu/arm920t/start.S +++ /dev/null @@ -1,436 +0,0 @@ -/* - * armboot - Startup Code for ARM920 CPU-core - * - * Copyright (c) 2001 Marius Gröger <mag@sysgo.de> - * Copyright (c) 2002 Alex Züpke <azu@sysgo.de> - * Copyright (c) 2002 Gary Jennejohn <garyj@denx.de> - * - * See file CREDITS for list of people who contributed to this - * project. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License as - * published by the Free Software Foundation; either version 2 of - * the License, or (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, - * MA 02111-1307 USA - */ - -#include <common.h> -#include <config.h> - -/* - ************************************************************************* - * - * Jump vector table as in table 3.1 in [1] - * - ************************************************************************* - */ - - -.globl _start -_start: b start_code - ldr pc, _undefined_instruction - ldr pc, _software_interrupt - ldr pc, _prefetch_abort - ldr pc, _data_abort - ldr pc, _not_used - ldr pc, _irq - ldr pc, _fiq - -_undefined_instruction: .word undefined_instruction -_software_interrupt: .word software_interrupt -_prefetch_abort: .word prefetch_abort -_data_abort: .word data_abort -_not_used: .word not_used -_irq: .word irq -_fiq: .word fiq - - .balignl 16,0xdeadbeef - - -/* - ************************************************************************* - * - * Startup Code (called from the ARM reset exception vector) - * - * do important init only if we don't start from memory! - * relocate armboot to ram - * setup stack - * jump to second stage - * - ************************************************************************* - */ - -_TEXT_BASE: - .word TEXT_BASE - -.globl _armboot_start -_armboot_start: - .word _start - -/* - * These are defined in the board-specific linker script. - */ -.globl _bss_start -_bss_start: - .word __bss_start - -.globl _bss_end -_bss_end: - .word _end - -#ifdef CONFIG_USE_IRQ -/* IRQ stack memory (calculated at run-time) */ -.globl IRQ_STACK_START -IRQ_STACK_START: - .word 0x0badc0de - -/* IRQ stack memory (calculated at run-time) */ -.globl FIQ_STACK_START -FIQ_STACK_START: - .word 0x0badc0de -#endif - - -/* - * the actual start code - */ - -start_code: - /* - * set the cpu to SVC32 mode - */ - mrs r0, cpsr - bic r0, r0, #0x1f - orr r0, r0, #0xd3 - msr cpsr, r0 - - bl coloured_LED_init - bl red_LED_on - -#if defined(CONFIG_AT91RM9200DK) || defined(CONFIG_AT91RM9200EK) - /* - * relocate exception table - */ - ldr r0, =_start - ldr r1, =0x0 - mov r2, #16 -copyex: - subs r2, r2, #1 - ldr r3, [r0], #4 - str r3, [r1], #4 - bne copyex -#endif - -#ifdef CONFIG_S3C24X0 - /* turn off the watchdog */ - -# if defined(CONFIG_S3C2400) -# define pWTCON 0x15300000 -# define INTMSK 0x14400008 /* Interupt-Controller base addresses */ -# define CLKDIVN 0x14800014 /* clock divisor register */ -#else -# define pWTCON 0x53000000 -# define INTMSK 0x4A000008 /* Interupt-Controller base addresses */ -# define INTSUBMSK 0x4A00001C -# define CLKDIVN 0x4C000014 /* clock divisor register */ -# endif - - ldr r0, =pWTCON - mov r1, #0x0 - str r1, [r0] - - /* - * mask all IRQs by setting all bits in the INTMR - default - */ - mov r1, #0xffffffff - ldr r0, =INTMSK - str r1, [r0] -# if defined(CONFIG_S3C2410) - ldr r1, =0x3ff - ldr r0, =INTSUBMSK - str r1, [r0] -# endif - - /* FCLK:HCLK:PCLK = 1:2:4 */ - /* default FCLK is 120 MHz ! */ - ldr r0, =CLKDIVN - mov r1, #3 - str r1, [r0] -#endif /* CONFIG_S3C24X0 */ - - /* - * we do sys-critical inits only at reboot, - * not when booting from ram! - */ -#ifndef CONFIG_SKIP_LOWLEVEL_INIT - bl cpu_init_crit -#endif - -#ifndef CONFIG_SKIP_RELOCATE_UBOOT -relocate: /* relocate U-Boot to RAM */ - adr r0, _start /* r0 <- current position of code */ - ldr r1, _TEXT_BASE /* test if we run from flash or RAM */ - cmp r0, r1 /* don't reloc during debug */ - beq stack_setup - - ldr r2, _armboot_start - ldr r3, _bss_start - sub r2, r3, r2 /* r2 <- size of armboot */ - add r2, r0, r2 /* r2 <- source end address */ - -copy_loop: - ldmia r0!, {r3-r10} /* copy from source address [r0] */ - stmia r1!, {r3-r10} /* copy to target address [r1] */ - cmp r0, r2 /* until source end addreee [r2] */ - ble copy_loop -#endif /* CONFIG_SKIP_RELOCATE_UBOOT */ - - /* Set up the stack */ -stack_setup: - ldr r0, _TEXT_BASE /* upper 128 KiB: relocated uboot */ - sub r0, r0, #CONFIG_SYS_MALLOC_LEN /* malloc area */ - sub r0, r0, #CONFIG_SYS_GBL_DATA_SIZE /* bdinfo */ -#ifdef CONFIG_USE_IRQ - sub r0, r0, #(CONFIG_STACKSIZE_IRQ+CONFIG_STACKSIZE_FIQ) -#endif - sub sp, r0, #12 /* leave 3 words for abort-stack */ - -clear_bss: - ldr r0, _bss_start /* find start of bss segment */ - ldr r1, _bss_end /* stop here */ - mov r2, #0x00000000 /* clear */ - -clbss_l:str r2, [r0] /* clear loop... */ - add r0, r0, #4 - cmp r0, r1 - ble clbss_l - - ldr pc, _start_armboot - -_start_armboot: .word start_armboot - - -/* - ************************************************************************* - * - * CPU_init_critical registers - * - * setup important registers - * setup memory timing - * - ************************************************************************* - */ - - -#ifndef CONFIG_SKIP_LOWLEVEL_INIT -cpu_init_crit: - /* - * flush v4 I/D caches - */ - mov r0, #0 - mcr p15, 0, r0, c7, c7, 0 /* flush v3/v4 cache */ - mcr p15, 0, r0, c8, c7, 0 /* flush v4 TLB */ - - /* - * disable MMU stuff and caches - */ - mrc p15, 0, r0, c1, c0, 0 - bic r0, r0, #0x00002300 @ clear bits 13, 9:8 (--V- --RS) - bic r0, r0, #0x00000087 @ clear bits 7, 2:0 (B--- -CAM) - orr r0, r0, #0x00000002 @ set bit 2 (A) Align - orr r0, r0, #0x00001000 @ set bit 12 (I) I-Cache - mcr p15, 0, r0, c1, c0, 0 - - /* - * before relocating, we have to setup RAM timing - * because memory timing is board-dependend, you will - * find a lowlevel_init.S in your board directory. - */ - mov ip, lr - - bl lowlevel_init - - mov lr, ip - mov pc, lr -#endif /* CONFIG_SKIP_LOWLEVEL_INIT */ - -/* - ************************************************************************* - * - * Interrupt handling - * - ************************************************************************* - */ - -@ -@ IRQ stack frame. -@ -#define S_FRAME_SIZE 72 - -#define S_OLD_R0 68 -#define S_PSR 64 -#define S_PC 60 -#define S_LR 56 -#define S_SP 52 - -#define S_IP 48 -#define S_FP 44 -#define S_R10 40 -#define S_R9 36 -#define S_R8 32 -#define S_R7 28 -#define S_R6 24 -#define S_R5 20 -#define S_R4 16 -#define S_R3 12 -#define S_R2 8 -#define S_R1 4 -#define S_R0 0 - -#define MODE_SVC 0x13 -#define I_BIT 0x80 - -/* - * use bad_save_user_regs for abort/prefetch/undef/swi ... - * use irq_save_user_regs / irq_restore_user_regs for IRQ/FIQ handling - */ - - .macro bad_save_user_regs - sub sp, sp, #S_FRAME_SIZE - stmia sp, {r0 - r12} @ Calling r0-r12 - ldr r2, _armboot_start - sub r2, r2, #(CONFIG_STACKSIZE) - sub r2, r2, #(CONFIG_SYS_MALLOC_LEN) - /* set base 2 words into abort stack */ - sub r2, r2, #(CONFIG_SYS_GBL_DATA_SIZE+8) - ldmia r2, {r2 - r3} @ get pc, cpsr - add r0, sp, #S_FRAME_SIZE @ restore sp_SVC - - add r5, sp, #S_SP - mov r1, lr - stmia r5, {r0 - r3} @ save sp_SVC, lr_SVC, pc, cpsr - mov r0, sp - .endm - - .macro irq_save_user_regs - sub sp, sp, #S_FRAME_SIZE - stmia sp, {r0 - r12} @ Calling r0-r12 - add r7, sp, #S_PC - stmdb r7, {sp, lr}^ @ Calling SP, LR - str lr, [r7, #0] @ Save calling PC - mrs r6, spsr - str r6, [r7, #4] @ Save CPSR - str r0, [r7, #8] @ Save OLD_R0 - mov r0, sp - .endm - - .macro irq_restore_user_regs - ldmia sp, {r0 - lr}^ @ Calling r0 - lr - mov r0, r0 - ldr lr, [sp, #S_PC] @ Get PC - add sp, sp, #S_FRAME_SIZE - /* return & move spsr_svc into cpsr */ - subs pc, lr, #4 - .endm - - .macro get_bad_stack - ldr r13, _armboot_start @ setup our mode stack - sub r13, r13, #(CONFIG_STACKSIZE) - sub r13, r13, #(CONFIG_SYS_MALLOC_LEN) - /* reserve a couple spots in abort stack */ - sub r13, r13, #(CONFIG_SYS_GBL_DATA_SIZE+8) - - str lr, [r13] @ save caller lr / spsr - mrs lr, spsr - str lr, [r13, #4] - - mov r13, #MODE_SVC @ prepare SVC-Mode - @ msr spsr_c, r13 - msr spsr, r13 - mov lr, pc - movs pc, lr - .endm - - .macro get_irq_stack @ setup IRQ stack - ldr sp, IRQ_STACK_START - .endm - - .macro get_fiq_stack @ setup FIQ stack - ldr sp, FIQ_STACK_START - .endm - -/* - * exception handlers - */ - .align 5 -undefined_instruction: - get_bad_stack - bad_save_user_regs - bl do_undefined_instruction - - .align 5 -software_interrupt: - get_bad_stack - bad_save_user_regs - bl do_software_interrupt - - .align 5 -prefetch_abort: - get_bad_stack - bad_save_user_regs - bl do_prefetch_abort - - .align 5 -data_abort: - get_bad_stack - bad_save_user_regs - bl do_data_abort - - .align 5 -not_used: - get_bad_stack - bad_save_user_regs - bl do_not_used - -#ifdef CONFIG_USE_IRQ - - .align 5 -irq: - get_irq_stack - irq_save_user_regs - bl do_irq - irq_restore_user_regs - - .align 5 -fiq: - get_fiq_stack - /* someone ought to write a more effiction fiq_save_user_regs */ - irq_save_user_regs - bl do_fiq - irq_restore_user_regs - -#else - - .align 5 -irq: - get_bad_stack - bad_save_user_regs - bl do_irq - - .align 5 -fiq: - get_bad_stack - bad_save_user_regs - bl do_fiq - -#endif |