diff options
Diffstat (limited to 'roms/u-boot/arch/arm/cpu/arm1136/start.S')
| -rw-r--r-- | roms/u-boot/arch/arm/cpu/arm1136/start.S | 346 |
1 files changed, 346 insertions, 0 deletions
diff --git a/roms/u-boot/arch/arm/cpu/arm1136/start.S b/roms/u-boot/arch/arm/cpu/arm1136/start.S new file mode 100644 index 00000000..3e2358e1 --- /dev/null +++ b/roms/u-boot/arch/arm/cpu/arm1136/start.S @@ -0,0 +1,346 @@ +/* + * armboot - Startup Code for OMP2420/ARM1136 CPU-core + * + * Copyright (c) 2004 Texas Instruments <r-woodruff2@ti.com> + * + * Copyright (c) 2001 Marius Gröger <mag@sysgo.de> + * Copyright (c) 2002 Alex Züpke <azu@sysgo.de> + * Copyright (c) 2002 Gary Jennejohn <garyj@denx.de> + * Copyright (c) 2003 Richard Woodruff <r-woodruff2@ti.com> + * Copyright (c) 2003 Kshitij <kshitij@ti.com> + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <asm-offsets.h> +#include <config.h> +#include <version.h> +.globl _start +_start: b reset +#ifdef CONFIG_SPL_BUILD + ldr pc, _hang + ldr pc, _hang + ldr pc, _hang + ldr pc, _hang + ldr pc, _hang + ldr pc, _hang + ldr pc, _hang + +_hang: + .word do_hang + .word 0x12345678 + .word 0x12345678 + .word 0x12345678 + .word 0x12345678 + .word 0x12345678 + .word 0x12345678 + .word 0x12345678 /* now 16*4=64 */ +#else + 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 +_pad: .word 0x12345678 /* now 16*4=64 */ +#endif /* CONFIG_SPL_BUILD */ +.global _end_vect +_end_vect: + + .balignl 16,0xdeadbeef +/* + ************************************************************************* + * + * Startup Code (reset vector) + * + * do important init only if we don't start from memory! + * setup Memory and board specific bits prior to relocation. + * relocate armboot to ram + * setup stack + * + ************************************************************************* + */ + +#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 + +/* IRQ stack memory (calculated at run-time) + 8 bytes */ +.globl IRQ_STACK_START_IN +IRQ_STACK_START_IN: + .word 0x0badc0de + +/* + * the actual reset code + */ + +reset: + /* + * set the cpu to SVC32 mode + */ + mrs r0,cpsr + bic r0,r0,#0x1f + orr r0,r0,#0xd3 + msr cpsr,r0 + + /* the mask ROM code should have PLL and others stable */ +#ifndef CONFIG_SKIP_LOWLEVEL_INIT + bl cpu_init_crit +#endif + + bl _main + +/*------------------------------------------------------------------------------*/ + + .globl c_runtime_cpu_setup +c_runtime_cpu_setup: + + bx lr + +/* + ************************************************************************* + * + * 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 /* Invalidate I+D+BTB caches */ + mcr p15, 0, r0, c8, c7, 0 /* Invalidate Unified 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 + + /* + * Jump to board specific initialization... The Mask ROM will have already initialized + * basic memory. Go here to bump up clock rate and handle wake up conditions. + */ + mov ip, lr /* persevere link reg across call */ + bl lowlevel_init /* go setup pll,mux,memory */ + mov lr, ip /* restore link */ + mov pc, lr /* back to my caller */ +#endif /* CONFIG_SKIP_LOWLEVEL_INIT */ + +#ifndef CONFIG_SPL_BUILD +/* + ************************************************************************* + * + * 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 @ carve out a frame on current user stack + stmia sp, {r0 - r12} @ Save user registers (now in svc mode) r0-r12 + + ldr r2, IRQ_STACK_START_IN @ set base 2 words into abort stack + ldmia r2, {r2 - r3} @ get values for "aborted" pc and cpsr (into parm regs) + add r0, sp, #S_FRAME_SIZE @ grab pointer to old stack + + add r5, sp, #S_SP + mov r1, lr + stmia r5, {r0 - r3} @ save sp_SVC, lr_SVC, pc, cpsr + mov r0, sp @ save current stack into r0 (param register) + .endm + + .macro irq_save_user_regs + sub sp, sp, #S_FRAME_SIZE + stmia sp, {r0 - r12} @ Calling r0-r12 + add r8, sp, #S_PC @ !!!! R8 NEEDS to be saved !!!! a reserved stack spot would be good. + stmdb r8, {sp, lr}^ @ Calling SP, LR + str lr, [r8, #0] @ Save calling PC + mrs r6, spsr + str r6, [r8, #4] @ Save CPSR + str r0, [r8, #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 + subs pc, lr, #4 @ return & move spsr_svc into cpsr + .endm + + .macro get_bad_stack + ldr r13, IRQ_STACK_START_IN @ setup our mode stack (enter in banked mode) + + str lr, [r13] @ save caller lr in position 0 of saved stack + mrs lr, spsr @ get the spsr + str lr, [r13, #4] @ save spsr in position 1 of saved stack + + mov r13, #MODE_SVC @ prepare SVC-Mode + @ msr spsr_c, r13 + msr spsr, r13 @ switch modes, make sure moves will execute + mov lr, pc @ capture return pc + movs pc, lr @ jump to next instruction & switch modes. + .endm + + .macro get_bad_stack_swi + sub r13, r13, #4 @ space on current stack for scratch reg. + str r0, [r13] @ save R0's value. + ldr r0, IRQ_STACK_START_IN @ get data regions start + str lr, [r0] @ save caller lr in position 0 of saved stack + mrs lr, spsr @ get the spsr + str lr, [r0, #4] @ save spsr in position 1 of saved stack + ldr lr, [r0] @ restore lr + ldr r0, [r13] @ restore r0 + add r13, r13, #4 @ pop stack entry + .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 +#endif /* CONFIG_SPL_BUILD */ + +/* + * exception handlers + */ +#ifdef CONFIG_SPL_BUILD + .align 5 +do_hang: + bl hang /* hang and never return */ +#else /* !CONFIG_SPL_BUILD */ + .align 5 +undefined_instruction: + get_bad_stack + bad_save_user_regs + bl do_undefined_instruction + + .align 5 +software_interrupt: + get_bad_stack_swi + 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 + .align 5 +.global arm1136_cache_flush +arm1136_cache_flush: +#if !defined(CONFIG_SYS_ICACHE_OFF) + mcr p15, 0, r1, c7, c5, 0 @ invalidate I cache +#endif +#if !defined(CONFIG_SYS_DCACHE_OFF) + mcr p15, 0, r1, c7, c14, 0 @ invalidate D cache +#endif + mov pc, lr @ back to caller +#endif /* CONFIG_SPL_BUILD */ |