| /* |
| * armboot - Startup Code for OMAP3530/ARM Cortex 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> |
| * Copyright (c) 2006-2008 Syed Mohammed Khasim <x0khasim@ti.com> |
| * |
| * 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 <config.h> |
| #include <version.h> |
| |
| .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 |
| _pad: .word 0x12345678 /* now 16*4=64 */ |
| .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 |
| * |
| *************************************************************************/ |
| |
| _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 reset code |
| */ |
| |
| reset: |
| /* |
| * set the cpu to SVC32 mode |
| */ |
| mrs r0, cpsr |
| bic r0, r0, #0x1f |
| orr r0, r0, #0xd3 |
| msr cpsr,r0 |
| |
| #if (CONFIG_OMAP34XX) |
| /* Copy vectors to mask ROM indirect addr */ |
| adr r0, _start @ r0 <- current position of code |
| add r0, r0, #4 @ skip reset vector |
| mov r2, #64 @ r2 <- size to copy |
| add r2, r0, r2 @ r2 <- source end address |
| mov r1, #SRAM_OFFSET0 @ build vect addr |
| mov r3, #SRAM_OFFSET1 |
| add r1, r1, r3 |
| mov r3, #SRAM_OFFSET2 |
| add r1, r1, r3 |
| next: |
| ldmia r0!, {r3 - r10} @ copy from source address [r0] |
| stmia r1!, {r3 - r10} @ copy to target address [r1] |
| cmp r0, r2 @ until source end address [r2] |
| bne next @ loop until equal */ |
| #if !defined(CONFIG_SYS_NAND_BOOT) && !defined(CONFIG_SYS_ONENAND_BOOT) |
| /* No need to copy/exec the clock code - DPLL adjust already done |
| * in NAND/oneNAND Boot. |
| */ |
| bl cpy_clk_code @ put dpll adjust code behind vectors |
| #endif /* NAND Boot */ |
| #endif |
| /* the mask ROM code should have PLL and others stable */ |
| #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: @ copy 32 bytes at a time |
| 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 |
| and sp, sp, #~7 @ 8 byte alinged for (ldr/str)d |
| |
| /* Clear BSS (if any). Is below tx (watch load addr - need space) */ |
| clear_bss: |
| ldr r0, _bss_start @ find start of bss segment |
| ldr r1, _bss_end @ stop here |
| mov r2, #0x00000000 @ clear value |
| clbss_l: |
| str r2, [r0] @ clear BSS location |
| cmp r0, r1 @ are we at the end yet |
| add r0, r0, #4 @ increment clear index pointer |
| bne clbss_l @ keep clearing till at end |
| |
| ldr pc, _start_armboot @ jump to C code |
| |
| _start_armboot: .word start_armboot |
| |
| |
| /************************************************************************* |
| * |
| * CPU_init_critical registers |
| * |
| * setup important registers |
| * setup memory timing |
| * |
| *************************************************************************/ |
| cpu_init_crit: |
| /* |
| * Invalidate L1 I/D |
| */ |
| mov r0, #0 @ set up for MCR |
| mcr p15, 0, r0, c8, c7, 0 @ invalidate TLBs |
| mcr p15, 0, r0, c7, c5, 0 @ invalidate icache |
| |
| /* |
| * disable MMU stuff and caches |
| */ |
| mrc p15, 0, r0, c1, c0, 0 |
| bic r0, r0, #0x00002000 @ clear bits 13 (--V-) |
| bic r0, r0, #0x00000007 @ clear bits 2:0 (-CAM) |
| orr r0, r0, #0x00000002 @ set bit 1 (--A-) Align |
| orr r0, r0, #0x00000800 @ set bit 12 (Z---) BTB |
| 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 |
| /* |
| ************************************************************************* |
| * |
| * 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, _armboot_start |
| sub r2, r2, #(CONFIG_SYS_MALLOC_LEN) |
| sub r2, r2, #(CONFIG_SYS_GBL_DATA_SIZE + 8) @ 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, _armboot_start @ setup our mode stack (enter |
| @ in banked mode) |
| sub r13, r13, #(CONFIG_SYS_MALLOC_LEN) @ move past malloc pool |
| sub r13, r13, #(CONFIG_SYS_GBL_DATA_SIZE + 8) @ move to reserved a couple |
| @ spots for abort stack |
| |
| 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, _armboot_start @ get data regions start |
| sub r0, r0, #(CONFIG_SYS_MALLOC_LEN) @ move past malloc pool |
| sub r0, r0, #(CONFIG_SYS_GBL_DATA_SIZE + 8) @ move past gbl and a couple |
| @ spots for abort stack |
| str lr, [r0] @ save caller lr in position 0 |
| @ of saved stack |
| mrs r0, spsr @ get the spsr |
| str lr, [r0, #4] @ save spsr in position 1 of |
| @ saved stack |
| 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 |
| |
| /* |
| * exception handlers |
| */ |
| .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 effective 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 |