u-boot/arch/arm/cpu/pxa/start.S
Marek Vasut 7f4cfcf40d PXA: Re-add the Dcache locking as RAM for pxa250
Signed-off-by: Marek Vasut <marek.vasut@gmail.com>
Cc: Stefan Herbrechtsmeier <sherbrec@cit-ec.uni-bielefeld.de>
Cc: Albert ARIBAUD <albert.u.boot@aribaud.net>
2011-12-06 23:59:31 +01:00

606 lines
14 KiB
ArmAsm

/*
* armboot - Startup Code for XScale CPU-core
*
* 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 Zuepke <azu@sysgo.de>
* Copyright (C) 2001 Marius Groger <mag@sysgo.de>
* Copyright (C) 2002 Alex Zupke <azu@sysgo.de>
* Copyright (C) 2002 Gary Jennejohn <garyj@denx.de>
* Copyright (C) 2002 Kyle Harris <kharris@nexus-tech.net>
* Copyright (C) 2003 Kai-Uwe Bloem <kai-uwe.bloem@auerswald.de>
* Copyright (C) 2003 Kshitij <kshitij@ti.com>
* Copyright (C) 2003 Richard Woodruff <r-woodruff2@ti.com>
* Copyright (C) 2003 Robert Schwebel <r.schwebel@pengutronix.de>
* Copyright (C) 2004 Texas Instruments <r-woodruff2@ti.com>
* Copyright (C) 2010 Marek Vasut <marek.vasut@gmail.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 <asm-offsets.h>
#include <config.h>
#include <version.h>
#ifdef CONFIG_PXA25X
#if ((CONFIG_SYS_INIT_SP_ADDR) != 0xfffff800)
#error "Init SP address must be set to 0xfffff800 for PXA250"
#endif
#endif
.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
*
*************************************************************************
*/
.globl _TEXT_BASE
_TEXT_BASE:
#ifdef CONFIG_SPL_BUILD
.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
#ifndef CONFIG_SKIP_LOWLEVEL_INIT
bl cpu_init_crit
#endif
#ifdef CONFIG_PXA250
bl lock_cache_for_stack
#endif
/* Set stackpointer in internal RAM to call board_init_f */
call_board_init_f:
ldr sp, =(CONFIG_SYS_INIT_SP_ADDR)
bic sp, sp, #7 /* 8-byte alignment for ABI compliance */
ldr r0, =0x00000000
bl board_init_f
/*------------------------------------------------------------------------------*/
#ifndef CONFIG_SPL_BUILD
/*
* void relocate_code (addr_sp, gd, addr_moni)
*
* This "function" does not return, instead it continues in RAM
* after relocating the monitor code.
*
*/
.globl relocate_code
relocate_code:
mov r4, r0 /* save addr_sp */
mov r5, r1 /* save addr of gd */
mov r6, r2 /* save addr of destination */
/* Set up the stack */
stack_setup:
mov sp, r4
/* Disable the Dcache RAM lock for stack now */
#ifdef CONFIG_PXA250
bl cpu_init_crit
#endif
adr r0, _start
cmp r0, r6
beq clear_bss /* skip relocation */
mov r1, r6 /* r1 <- scratch for copy_loop */
ldr r3, _bss_start_ofs
add r2, r0, r3 /* r2 <- source end address */
copy_loop:
ldmia r0!, {r9-r10} /* copy from source address [r0] */
stmia r1!, {r9-r10} /* copy to target address [r1] */
cmp r0, r2 /* until source end address [r2] */
blo copy_loop
#ifndef CONFIG_SPL_BUILD
/*
* fix .rel.dyn relocations
*/
ldr r0, _TEXT_BASE /* r0 <- Text base */
sub r9, r6, r0 /* r9 <- relocation offset */
ldr r10, _dynsym_start_ofs /* r10 <- sym table ofs */
add r10, r10, r0 /* r10 <- sym table in FLASH */
ldr r2, _rel_dyn_start_ofs /* r2 <- rel dyn start ofs */
add r2, r2, r0 /* r2 <- rel dyn start in FLASH */
ldr r3, _rel_dyn_end_ofs /* r3 <- rel dyn end ofs */
add r3, r3, r0 /* r3 <- rel dyn end in FLASH */
fixloop:
ldr r0, [r2] /* r0 <- location to fix up, IN FLASH! */
add r0, r0, r9 /* r0 <- location to fix up in RAM */
ldr r1, [r2, #4]
and r7, r1, #0xff
cmp r7, #23 /* relative fixup? */
beq fixrel
cmp r7, #2 /* absolute fixup? */
beq fixabs
/* ignore unknown type of fixup */
b fixnext
fixabs:
/* absolute fix: set location to (offset) symbol value */
mov r1, r1, LSR #4 /* r1 <- symbol index in .dynsym */
add r1, r10, r1 /* r1 <- address of symbol in table */
ldr r1, [r1, #4] /* r1 <- symbol value */
add r1, r1, r9 /* r1 <- relocated sym addr */
b fixnext
fixrel:
/* relative fix: increase location by offset */
ldr r1, [r0]
add r1, r1, r9
fixnext:
str r1, [r0]
add r2, r2, #8 /* each rel.dyn entry is 8 bytes */
cmp r2, r3
blo fixloop
#endif
clear_bss:
#ifndef CONFIG_SPL_BUILD
ldr r0, _bss_start_ofs
ldr r1, _bss_end_ofs
mov r4, r6 /* reloc addr */
add r0, r0, r4
add r1, r1, r4
mov r2, #0x00000000 /* clear */
clbss_l:str r2, [r0] /* clear loop... */
add r0, r0, #4
cmp r0, r1
bne clbss_l
#endif /* #ifndef CONFIG_SPL_BUILD */
/*
* We are done. Do not return, instead branch to second part of board
* initialization, now running from RAM.
*/
#ifdef CONFIG_ONENAND_SPL
ldr r0, _onenand_boot_ofs
mov pc, r0
_onenand_boot_ofs:
.word onenand_boot
#else
jump_2_ram:
ldr r0, _board_init_r_ofs
ldr r1, _TEXT_BASE
add lr, r0, r1
add lr, lr, r9
/* setup parameters for board_init_r */
mov r0, r5 /* gd_t */
mov r1, r6 /* dest_addr */
/* jump to it ... */
mov pc, lr
_board_init_r_ofs:
.word board_init_r - _start
#endif
_rel_dyn_start_ofs:
.word __rel_dyn_start - _start
_rel_dyn_end_ofs:
.word __rel_dyn_end - _start
_dynsym_start_ofs:
.word __dynsym_start - _start
#endif
/*
*************************************************************************
*
* CPU_init_critical registers
*
* setup important registers
* setup memory timing
*
*************************************************************************
*/
#if !defined(CONFIG_SKIP_LOWLEVEL_INIT) || defined(CONFIG_PXA250)
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
mov pc, lr /* back to my caller */
#endif /* !CONFIG_SKIP_LOWLEVEL_INIT || CONFIG_PXA250 */
#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 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
#endif /* CONFIG_SPL_BUILD */
/*
* exception handlers
*/
#ifdef CONFIG_SPL_BUILD
.align 5
do_hang:
ldr sp, _TEXT_BASE /* use 32 words about stack */
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
#endif /* CONFIG_SPL_BUILD */
/*
* Enable MMU to use DCache as DRAM.
*
* This is useful on PXA25x and PXA26x in early bootstages, where there is no
* other possible memory available to hold stack.
*/
#ifdef CONFIG_PXA250
.macro CPWAIT reg
mrc p15, 0, \reg, c2, c0, 0
mov \reg, \reg
sub pc, pc, #4
.endm
lock_cache_for_stack:
/* Domain access -- enable for all CPs */
ldr r0, =0x0000ffff
mcr p15, 0, r0, c3, c0, 0
/* Point TTBR to MMU table */
ldr r0, =mmutable
mcr p15, 0, r0, c2, c0, 0
/* Kick in MMU, ICache, DCache, BTB */
mrc p15, 0, r0, c1, c0, 0
bic r0, #0x1b00
bic r0, #0x0087
orr r0, #0x1800
orr r0, #0x0005
mcr p15, 0, r0, c1, c0, 0
CPWAIT r0
/* Unlock Icache, Dcache */
mcr p15, 0, r0, c9, c1, 1
mcr p15, 0, r0, c9, c2, 1
/* Flush Icache, Dcache, BTB */
mcr p15, 0, r0, c7, c7, 0
/* Unlock I-TLB, D-TLB */
mcr p15, 0, r0, c10, c4, 1
mcr p15, 0, r0, c10, c8, 1
/* Flush TLB */
mcr p15, 0, r0, c8, c7, 0
/* Allocate 4096 bytes of Dcache as RAM */
/* Drain pending loads and stores */
mcr p15, 0, r0, c7, c10, 4
mov r4, #0x00
mov r5, #0x00
mov r2, #0x01
mcr p15, 0, r0, c9, c2, 0
CPWAIT r0
/* 128 lines reserved (128 x 32bytes = 4096 bytes total) */
mov r0, #128
ldr r1, =0xfffff000
alloc:
mcr p15, 0, r1, c7, c2, 5
/* Drain pending loads and stores */
mcr p15, 0, r0, c7, c10, 4
strd r4, [r1], #8
strd r4, [r1], #8
strd r4, [r1], #8
strd r4, [r1], #8
subs r0, #0x01
bne alloc
/* Drain pending loads and stores */
mcr p15, 0, r0, c7, c10, 4
mov r2, #0x00
mcr p15, 0, r2, c9, c2, 0
CPWAIT r0
mov pc, lr
.section .mmutable, "a"
mmutable:
.align 14
/* 0x00000000 - 0xffe00000 : 1:1, uncached mapping */
.set __base, 0
.rept 0xfff
.word (__base << 20) | 0xc12
.set __base, __base + 1
.endr
/* 0xfff00000 : 1:1, cached mapping */
.word (0xfff << 20) | 0x1c1e
#endif /* CONFIG_PXA250 */