u-boot/cpu/pxa/start.S
Marcel Ziswiler 2a4741d9a1 fix pxa255_idp board
The pxa255_idp being an old unmaintained board showed several issues:
1. CONFIG_INIT_CRITICAL was still defined.
2. Neither CONFIG_MAC_PARTITION nor CONFIG_DOS_PARTITION was defined.
3. Symbol flash_addr was undeclared.
4. The boards lowlevel_init function was still called memsetup.
5. The TEXT_BASE was still 0xa3000000 rather than 0xa3080000.
6. Using -march=armv5 instead of -march=armv5te resulted in lots of
'target CPU does not support interworking' warnings on recent compilers.
7. The PXA's serial driver redefined FFUART, BTUART and STUART used as
indexes rather than the register definitions from the pxa-regs header
file. Renamed them to FFUART_INDEX, BTUART_INDEX and STUART_INDEX to
avoid any ambiguities.
8. There were several redefinition warnings concerning ICMR, OSMR3,
OSCR, OWER, OIER, RCSR and CCCR in the PXA's assembly start file.
9. The board configuration file was rather outdated.
10. The part header file defined the vendor, product and revision arrays
as unsigned chars instead of just chars in the block_dev_desc_t
structure.

Signed-off-by: Marcel Ziswiler <marcel@ziswiler.com>
2007-10-23 16:40:40 +02:00

502 lines
12 KiB
ArmAsm

/*
* armboot - Startup Code for XScale
*
* 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) 2002 Kyle Harris <kharris@nexus-tech.net>
* Copyright (C) 2003 Robert Schwebel <r.schwebel@pengutronix.de>
* Copyright (C) 2003 Kai-Uwe Bloem <kai-uwe.bloem@auerswald.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
*/
#include <config.h>
#include <version.h>
#include <asm/arch/pxa-regs.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
.balignl 16,0xdeadbeef
/*
* Startup Code (reset vector)
*
* do important init only if we don't start from RAM!
* - relocate armboot to ram
* - setup stack
* - jump to second stage
*/
_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:
mrs r0,cpsr /* set the cpu to SVC32 mode */
bic r0,r0,#0x1f /* (superviser mode, M=10011) */
orr r0,r0,#0x13
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 /* we do sys-critical inits */
#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:
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, #CFG_MALLOC_LEN /* malloc area */
sub r0, r0, #CFG_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 */
clear_bss:
ldr r0, _bss_start /* find start of bss segment */
ldr r1, _bss_end /* stop here */
mov r2, #0x00000000 /* clear */
clbss_l:str r2, [r0] /* clear loop... */
add r0, r0, #4
cmp r0, r1
ble clbss_l
ldr pc, _start_armboot
_start_armboot: .word start_armboot
/****************************************************************************/
/* */
/* CPU_init_critical registers */
/* */
/* - setup important registers */
/* - setup memory timing */
/* */
/****************************************************************************/
/* mk@tbd: Fix this! */
#if defined(CONFIG_PXA250) || defined(CONFIG_CPU_MONAHANS)
#undef ICMR
#undef OSMR3
#undef OSCR
#undef OWER
#undef OIER
#endif
#ifdef CONFIG_PXA250
#undef RCSR
#undef CCCR
#endif
/* Interrupt-Controller base address */
IC_BASE: .word 0x40d00000
#define ICMR 0x04
/* Reset-Controller */
RST_BASE: .word 0x40f00030
#define RCSR 0x00
/* Operating System Timer */
OSTIMER_BASE: .word 0x40a00000
#define OSMR3 0x0C
#define OSCR 0x10
#define OWER 0x18
#define OIER 0x1C
/* Clock Manager Registers */
#ifdef CONFIG_CPU_MONAHANS
# ifndef CFG_MONAHANS_RUN_MODE_OSC_RATIO
# error "You have to define CFG_MONAHANS_RUN_MODE_OSC_RATIO!!"
# endif
# ifndef CFG_MONAHANS_TURBO_RUN_MODE_RATIO
# define CFG_MONAHANS_TURBO_RUN_MODE_RATIO 0x1
# endif
#else /* ! CONFIG_CPU_MONAHANS */
#ifdef CFG_CPUSPEED
CC_BASE: .word 0x41300000
#define CCCR 0x00
cpuspeed: .word CFG_CPUSPEED
#else
#error "You have to define CFG_CPUSPEED!!"
#endif
#endif /* CONFIG_CPU_MONAHANS */
/* takes care the CP15 update has taken place */
.macro CPWAIT reg
mrc p15,0,\reg,c2,c0,0
mov \reg,\reg
sub pc,pc,#4
.endm
cpu_init_crit:
/* mask all IRQs */
#ifndef CONFIG_CPU_MONAHANS
ldr r0, IC_BASE
mov r1, #0x00
str r1, [r0, #ICMR]
#else
/* Step 1 - Enable CP6 permission */
mrc p15, 0, r1, c15, c1, 0 @ read CPAR
orr r1, r1, #0x40
mcr p15, 0, r1, c15, c1, 0
CPWAIT r1
/* Step 2 - Mask ICMR & ICMR2 */
mov r1, #0
mcr p6, 0, r1, c1, c0, 0 @ ICMR
mcr p6, 0, r1, c7, c0, 0 @ ICMR2
/* turn off all clocks but the ones we will definitly require */
ldr r1, =CKENA
ldr r2, =(CKENA_22_FFUART | CKENA_10_SRAM | CKENA_9_SMC | CKENA_8_DMC)
str r2, [r1]
ldr r1, =CKENB
ldr r2, =(CKENB_6_IRQ)
str r2, [r1]
#endif
/* set clock speed */
#ifdef CONFIG_CPU_MONAHANS
ldr r0, =ACCR
ldr r1, =(((CFG_MONAHANS_TURBO_RUN_MODE_RATIO<<8) & ACCR_XN_MASK) | (CFG_MONAHANS_RUN_MODE_OSC_RATIO & ACCR_XL_MASK))
str r1, [r0]
#else /* ! CONFIG_CPU_MONAHANS */
#ifdef CFG_CPUSPEED
ldr r0, CC_BASE
ldr r1, cpuspeed
str r1, [r0, #CCCR]
mov r0, #2
mcr p14, 0, r0, c6, c0, 0
setspeed_done:
#endif /* CFG_CPUSPEED */
#endif /* CONFIG_CPU_MONAHANS */
/*
* 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
/* Memory interfaces are working. Disable MMU and enable I-cache. */
/* mk: hmm, this is not in the monahans docs, leave it now but
* check here if it doesn't work :-) */
ldr r0, =0x2001 /* enable access to all coproc. */
mcr p15, 0, r0, c15, c1, 0
CPWAIT r0
mcr p15, 0, r0, c7, c10, 4 /* drain the write & fill buffers */
CPWAIT r0
mcr p15, 0, r0, c7, c7, 0 /* flush Icache, Dcache and BTB */
CPWAIT r0
mcr p15, 0, r0, c8, c7, 0 /* flush instuction and data TLBs */
CPWAIT r0
/* Enable the Icache */
/*
mrc p15, 0, r0, c1, c0, 0
orr r0, r0, #0x1800
mcr p15, 0, r0, c1, c0, 0
CPWAIT
*/
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
/* use bad_save_user_regs for abort/prefetch/undef/swi ... */
.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, _armboot_start
sub r2, r2, #(CONFIG_STACKSIZE+CFG_MALLOC_LEN)
sub r2, r2, #(CFG_GBL_DATA_SIZE+8) @ set base 2 words into abort stack
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
/* use irq_save_user_regs / irq_restore_user_regs for */
/* IRQ/FIQ handling */
.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, _armboot_start @ setup our mode stack
sub r13, r13, #(CONFIG_STACKSIZE+CFG_MALLOC_LEN)
sub r13, r13, #(CFG_GBL_DATA_SIZE+8) @ reserved a couple spots in abort 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
irq_save_user_regs /* someone ought to write a more */
bl do_fiq /* effiction fiq_save_user_regs */
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
/****************************************************************************/
/* */
/* Reset function: the PXA250 doesn't have a reset function, so we have to */
/* perform a watchdog timeout for a soft reset. */
/* */
/****************************************************************************/
.align 5
.globl reset_cpu
/* FIXME: this code is PXA250 specific. How is this handled on */
/* other XScale processors? */
reset_cpu:
/* We set OWE:WME (watchdog enable) and wait until timeout happens */
ldr r0, OSTIMER_BASE
ldr r1, [r0, #OWER]
orr r1, r1, #0x0001 /* bit0: WME */
str r1, [r0, #OWER]
/* OS timer does only wrap every 1165 seconds, so we have to set */
/* the match register as well. */
ldr r1, [r0, #OSCR] /* read OS timer */
add r1, r1, #0x800 /* let OSMR3 match after */
add r1, r1, #0x800 /* 4096*(1/3.6864MHz)=1ms */
str r1, [r0, #OSMR3]
reset_endless:
b reset_endless