u-boot-brain/cpu/arm1176/start.S
Seunghyeon Rhee a59a23d68a S3C6400/SMDK6400: fix stack_setup in start.S
Fix stack_setup to place the stack on the correct address in DRAM
accroding to U-Boot standard and remove conditional compilation by
CONFIG_MEMORY_UPPER_CODE macro that is not necessry. This macro
was introduced and used only by this board for some unclear reason.

The definition of this macro is also removed because it's not
referenced elsewhere.

Signed-off-by: Seunghyeon Rhee <seunghyeon@lpmtec.com>
Tested-by: Minkyu Kang <mk7.kang@samsung.com>
2009-11-27 16:26:13 -06:00

465 lines
10 KiB
ArmAsm

/*
* armboot - Startup Code for S3C6400/ARM1176 CPU-core
*
* Copyright (c) 2007 Samsung Electronics
*
* Copyright (C) 2008
* Guennadi Liakhovetki, DENX Software Engineering, <lg@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
*
* 2007-09-21 - Restructured codes by jsgood (jsgood.yang@samsung.com)
* 2007-09-21 - Added MoviNAND and OneNAND boot codes by
* jsgood (jsgood.yang@samsung.com)
* Base codes by scsuh (sc.suh)
*/
#include <config.h>
#include <version.h>
#ifdef CONFIG_ENABLE_MMU
#include <asm/proc/domain.h>
#endif
#include <asm/arch/s3c6400.h>
#if !defined(CONFIG_ENABLE_MMU) && !defined(CONFIG_SYS_PHY_UBOOT_BASE)
#define CONFIG_SYS_PHY_UBOOT_BASE CONFIG_SYS_UBOOT_BASE
#endif
/*
*************************************************************************
*
* Jump vector table as in table 3.1 in [1]
*
*************************************************************************
*/
.globl _start
_start: b reset
#ifndef CONFIG_NAND_SPL
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 */
#else
. = _start + 64
#endif
.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
/*
* Below variable is very important because we use MMU in U-Boot.
* Without it, we cannot run code correctly before MMU is ON.
* by scsuh.
*/
_TEXT_PHY_BASE:
.word CONFIG_SYS_PHY_UBOOT_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
/*
* the actual reset code
*/
reset:
/*
* set the cpu to SVC32 mode
*/
mrs r0, cpsr
bic r0, r0, #0x3f
orr r0, r0, #0xd3
msr cpsr, r0
/*
*************************************************************************
*
* CPU_init_critical registers
*
* setup important registers
* setup memory timing
*
*************************************************************************
*/
/*
* we do sys-critical inits only at reboot,
* not when booting from ram!
*/
cpu_init_crit:
/*
* When booting from NAND - it has definitely been a reset, so, no need
* to flush caches and disable the MMU
*/
#ifndef CONFIG_NAND_SPL
/*
* 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
/* Prepare to disable the MMU */
adr r1, mmu_disable_phys
/* We presume we're within the first 1024 bytes */
and r1, r1, #0x3fc
ldr r2, _TEXT_PHY_BASE
ldr r3, =0xfff00000
and r2, r2, r3
orr r2, r2, r1
b mmu_disable
.align 5
/* Run in a single cache-line */
mmu_disable:
mcr p15, 0, r0, c1, c0, 0
nop
nop
mov pc, r2
#endif
mmu_disable_phys:
/* Peri port setup */
ldr r0, =0x70000000
orr r0, r0, #0x13
mcr p15,0,r0,c15,c2,4 @ 256M (0x70000000 - 0x7fffffff)
/*
* Go setup Memory and board specific bits prior to relocation.
*/
bl lowlevel_init /* go setup pll,mux,memory */
after_copy:
#ifdef CONFIG_ENABLE_MMU
enable_mmu:
/* enable domain access */
ldr r5, =0x0000ffff
mcr p15, 0, r5, c3, c0, 0 /* load domain access register */
/* Set the TTB register */
ldr r0, _mmu_table_base
ldr r1, =CONFIG_SYS_PHY_UBOOT_BASE
ldr r2, =0xfff00000
bic r0, r0, r2
orr r1, r0, r1
mcr p15, 0, r1, c2, c0, 0
/* Enable the MMU */
mrc p15, 0, r0, c1, c0, 0
orr r0, r0, #1 /* Set CR_M to enable MMU */
/* Prepare to enable the MMU */
adr r1, skip_hw_init
and r1, r1, #0x3fc
ldr r2, _TEXT_BASE
ldr r3, =0xfff00000
and r2, r2, r3
orr r2, r2, r1
b mmu_enable
.align 5
/* Run in a single cache-line */
mmu_enable:
mcr p15, 0, r0, c1, c0, 0
nop
nop
mov pc, r2
#endif
skip_hw_init:
/* Set up the stack */
stack_setup:
ldr r0, =CONFIG_SYS_UBOOT_BASE /* base of copy in DRAM */
sub r0, r0, #CONFIG_SYS_MALLOC_LEN /* malloc area */
sub r0, r0, #CONFIG_SYS_GBL_DATA_SIZE /* bdinfo */
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, #0 /* clear */
clbss_l:
str r2, [r0] /* clear loop... */
add r0, r0, #4
cmp r0, r1
ble clbss_l
#ifndef CONFIG_NAND_SPL
ldr pc, _start_armboot
_start_armboot:
.word start_armboot
#else
b nand_boot
/* .word nand_boot*/
#endif
#ifdef CONFIG_ENABLE_MMU
_mmu_table_base:
.word mmu_table
#endif
#ifndef CONFIG_NAND_SPL
/*
* we assume that cache operation is done before. (eg. cleanup_before_linux())
* actually, we don't need to do anything about cache if not use d-cache in
* U-Boot. So, in this function we clean only MMU. by scsuh
*
* void theLastJump(void *kernel, int arch_num, uint boot_params);
*/
#ifdef CONFIG_ENABLE_MMU
.globl theLastJump
theLastJump:
mov r9, r0
ldr r3, =0xfff00000
ldr r4, _TEXT_PHY_BASE
adr r5, phy_last_jump
bic r5, r5, r3
orr r5, r5, r4
mov pc, r5
phy_last_jump:
/*
* disable MMU stuff
*/
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
mcr p15, 0, r0, c8, c7, 0 /* flush v4 TLB */
mov r0, #0
mov pc, r9
#endif
/*
*************************************************************************
*
* 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 ...
*/
.macro bad_save_user_regs
/* carve out a frame on current user stack */
sub sp, sp, #S_FRAME_SIZE
/* Save user registers (now in svc mode) r0-r12 */
stmia sp, {r0 - r12}
ldr r2, _armboot_start
sub r2, r2, #(CONFIG_SYS_MALLOC_LEN)
/* set base 2 words into abort stack */
sub r2, r2, #(CONFIG_SYS_GBL_DATA_SIZE+8)
/* get values for "aborted" pc and cpsr (into parm regs) */
ldmia r2, {r2 - r3}
/* grab pointer to old stack */
add r0, sp, #S_FRAME_SIZE
add r5, sp, #S_SP
mov r1, lr
/* save sp_SVC, lr_SVC, pc, cpsr */
stmia r5, {r0 - r3}
/* save current stack into r0 (param register) */
mov r0, sp
.endm
.macro get_bad_stack
/* setup our mode stack (enter in banked mode) */
ldr r13, _armboot_start
/* move past malloc pool */
sub r13, r13, #(CONFIG_SYS_MALLOC_LEN)
/* move to reserved a couple spots for abort stack */
sub r13, r13, #(CONFIG_SYS_GBL_DATA_SIZE + 8)
/* save caller lr in position 0 of saved stack */
str lr, [r13]
/* get the spsr */
mrs lr, spsr
/* save spsr in position 1 of saved stack */
str lr, [r13, #4]
/* prepare SVC-Mode */
mov r13, #MODE_SVC
@ msr spsr_c, r13
/* switch modes, make sure moves will execute */
msr spsr, r13
/* capture return pc */
mov lr, pc
/* jump to next instruction & switch modes. */
movs pc, lr
.endm
.macro get_bad_stack_swi
/* space on current stack for scratch reg. */
sub r13, r13, #4
/* save R0's value. */
str r0, [r13]
/* get data regions start */
ldr r0, _armboot_start
/* move past malloc pool */
sub r0, r0, #(CONFIG_SYS_MALLOC_LEN)
/* move past gbl and a couple spots for abort stack */
sub r0, r0, #(CONFIG_SYS_GBL_DATA_SIZE + 8)
/* save caller lr in position 0 of saved stack */
str lr, [r0]
/* get the spsr */
mrs r0, spsr
/* save spsr in position 1 of saved stack */
str lr, [r0, #4]
/* restore r0 */
ldr r0, [r13]
/* pop stack entry */
add r13, r13, #4
.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
.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 /* CONFIG_NAND_SPL */