| /* |
| * armboot - Startup Code for SA1100 CPU |
| * |
| * Copyright (C) 1998 Dan Malek <dmalek@jlc.net> |
| * Copyright (C) 1999 Magnus Damm <kieraypc01.p.y.kie.era.ericsson.se> |
| * Copyright (C) 2000 Wolfgang Denk <wd@denx.de> |
| * Copyright (c) 2001 Alex Züpke <azu@sysgo.de> |
| * |
| * SPDX-License-Identifier: GPL-2.0+ |
| */ |
| |
| #include <asm-offsets.h> |
| #include <config.h> |
| #include <version.h> |
| |
| /* |
| ************************************************************************* |
| * |
| * Jump vector table as in table 3.1 in [1] |
| * |
| ************************************************************************* |
| */ |
| |
| |
| .globl _start |
| _start: b reset |
| 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 (reset vector) |
| * |
| * do important init only if we don't start from memory! |
| * relocate armboot to ram |
| * setup stack |
| * jump to second stage |
| * |
| ************************************************************************* |
| */ |
| |
| .globl _TEXT_BASE |
| _TEXT_BASE: |
| #if defined(CONFIG_SPL_BUILD) && defined(CONFIG_SPL_TEXT_BASE) |
| .word CONFIG_SPL_TEXT_BASE |
| #else |
| .word CONFIG_SYS_TEXT_BASE |
| #endif |
| |
| /* |
| * These are defined in the board-specific linker script. |
| * Subtracting _start from them lets the linker put their |
| * relative position in the executable instead of leaving |
| * them null. |
| */ |
| .globl _bss_start_ofs |
| _bss_start_ofs: |
| .word __bss_start - _start |
| |
| .globl _bss_end_ofs |
| _bss_end_ofs: |
| .word __bss_end - _start |
| |
| .globl _end_ofs |
| _end_ofs: |
| .word _end - _start |
| |
| #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 |
| |
| /* |
| * we do sys-critical inits only at reboot, |
| * not when booting from ram! |
| */ |
| #ifndef CONFIG_SKIP_LOWLEVEL_INIT |
| bl cpu_init_crit |
| #endif |
| |
| bl _main |
| |
| /*------------------------------------------------------------------------------*/ |
| |
| .globl c_runtime_cpu_setup |
| c_runtime_cpu_setup: |
| |
| mov pc, lr |
| |
| /* |
| ************************************************************************* |
| * |
| * CPU_init_critical registers |
| * |
| * setup important registers |
| * setup memory timing |
| * |
| ************************************************************************* |
| */ |
| |
| |
| /* Interrupt-Controller base address */ |
| IC_BASE: .word 0x90050000 |
| #define ICMR 0x04 |
| |
| |
| /* Reset-Controller */ |
| RST_BASE: .word 0x90030000 |
| #define RSRR 0x00 |
| #define RCSR 0x04 |
| |
| |
| /* PWR */ |
| PWR_BASE: .word 0x90020000 |
| #define PSPR 0x08 |
| #define PPCR 0x14 |
| cpuspeed: .word CONFIG_SYS_CPUSPEED |
| |
| |
| cpu_init_crit: |
| /* |
| * mask all IRQs |
| */ |
| ldr r0, IC_BASE |
| mov r1, #0x00 |
| str r1, [r0, #ICMR] |
| |
| /* set clock speed */ |
| ldr r0, PWR_BASE |
| ldr r1, cpuspeed |
| str r1, [r0, #PPCR] |
| |
| /* |
| * 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 |
| |
| /* |
| * disable MMU stuff and enable I-cache |
| */ |
| mrc p15,0,r0,c1,c0 |
| bic r0, r0, #0x00002000 @ clear bit 13 (X) |
| bic r0, r0, #0x0000000f @ clear bits 3-0 (WCAM) |
| orr r0, r0, #0x00001000 @ set bit 12 (I) Icache |
| orr r0, r0, #0x00000002 @ set bit 2 (A) Align |
| mcr p15,0,r0,c1,c0 |
| |
| /* |
| * 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 */ |
| |
| mov pc, lr |
| |
| |
| /* |
| ************************************************************************* |
| * |
| * 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 |
| add r8, sp, #S_PC |
| |
| ldr r2, IRQ_STACK_START_IN |
| ldmia r2, {r2 - r4} @ get pc, cpsr, old_r0 |
| add r0, sp, #S_FRAME_SIZE @ restore sp_SVC |
| |
| add r5, sp, #S_SP |
| mov r1, lr |
| stmia r5, {r0 - r4} @ save sp_SVC, lr_SVC, pc, cpsr, old_r |
| mov r0, sp |
| .endm |
| |
| .macro irq_save_user_regs |
| sub sp, sp, #S_FRAME_SIZE |
| stmia sp, {r0 - r12} @ Calling r0-r12 |
| add r8, sp, #S_PC |
| 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 |
| |
| 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 |
| 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 |
| |
| .align 5 |
| .globl reset_cpu |
| reset_cpu: |
| ldr r0, RST_BASE |
| mov r1, #0x0 @ set bit 3-0 ... |
| str r1, [r0, #RCSR] @ ... to clear in RCSR |
| mov r1, #0x1 |
| str r1, [r0, #RSRR] @ and perform reset |
| b reset_cpu @ silly, but repeat endlessly |