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u-boot/cpu/mpc5xx/start.S
Wolfgang Denk 1636d1c852 Coding stylke cleanup; rebuild CHANGELOG
2007-06-22 23:59:00 +02:00

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ArmAsm
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/*
* Copyright (C) 1998 Dan Malek <dmalek@jlc.net>
* Copyright (C) 1999 Magnus Damm <kieraypc01.p.y.kie.era.ericsson.se>
* Copyright (C) 2000, 2001, 2002 Wolfgang Denk <wd@denx.de>
* Copyright (C) 2003 Martin Winistoerfer, martinwinistoerfer@gmx.ch.
*
* 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
*/
/*
* File: start.S
*
* Discription: startup code
*
*/
#include <config.h>
#include <mpc5xx.h>
#include <version.h>
#define CONFIG_5xx 1 /* needed for Linux kernel header files */
#define _LINUX_CONFIG_H 1 /* avoid reading Linux autoconf.h file */
#include <ppc_asm.tmpl>
#include <ppc_defs.h>
#include <linux/config.h>
#include <asm/processor.h>
#ifndef CONFIG_IDENT_STRING
#define CONFIG_IDENT_STRING ""
#endif
/* We don't have a MMU.
*/
#undef MSR_KERNEL
#define MSR_KERNEL ( MSR_ME | MSR_RI ) /* Machine Check and Recoverable Interr. */
/*
* Set up GOT: Global Offset Table
*
* Use r14 to access the GOT
*/
START_GOT
GOT_ENTRY(_GOT2_TABLE_)
GOT_ENTRY(_FIXUP_TABLE_)
GOT_ENTRY(_start)
GOT_ENTRY(_start_of_vectors)
GOT_ENTRY(_end_of_vectors)
GOT_ENTRY(transfer_to_handler)
GOT_ENTRY(__init_end)
GOT_ENTRY(_end)
GOT_ENTRY(__bss_start)
END_GOT
/*
* r3 - 1st arg to board_init(): IMMP pointer
* r4 - 2nd arg to board_init(): boot flag
*/
.text
.long 0x27051956 /* U-Boot Magic Number */
.globl version_string
version_string:
.ascii U_BOOT_VERSION
.ascii " (", __DATE__, " - ", __TIME__, ")"
.ascii CONFIG_IDENT_STRING, "\0"
. = EXC_OFF_SYS_RESET
.globl _start
_start:
mfspr r3, 638
li r4, CFG_ISB /* Set ISB bit */
or r3, r3, r4
mtspr 638, r3
li r21, BOOTFLAG_COLD /* Normal Power-On: Boot from FLASH */
b boot_cold
. = EXC_OFF_SYS_RESET + 0x20
.globl _start_warm
_start_warm:
li r21, BOOTFLAG_WARM /* Software reboot */
b boot_warm
boot_cold:
boot_warm:
/* Initialize machine status; enable machine check interrupt */
/*----------------------------------------------------------------------*/
li r3, MSR_KERNEL /* Set ME, RI flags */
mtmsr r3
mtspr SRR1, r3 /* Make SRR1 match MSR */
/* Initialize debug port registers */
/*----------------------------------------------------------------------*/
xor r0, r0, r0 /* Clear R0 */
mtspr LCTRL1, r0 /* Initialize debug port regs */
mtspr LCTRL2, r0
mtspr COUNTA, r0
mtspr COUNTB, r0
#if defined(CONFIG_PATI)
/* the external flash access on PATI fails if programming the PLL to 40MHz.
* Copy the PLL programming code to the internal RAM and execute it
*----------------------------------------------------------------------*/
lis r3, CFG_MONITOR_BASE@h
ori r3, r3, CFG_MONITOR_BASE@l
addi r3, r3, pll_prog_code_start - _start + EXC_OFF_SYS_RESET
lis r4, CFG_INIT_RAM_ADDR@h
ori r4, r4, CFG_INIT_RAM_ADDR@l
mtlr r4
addis r5,0,0x0
ori r5,r5,((pll_prog_code_end - pll_prog_code_start) >>2)
mtctr r5
addi r3, r3, -4
addi r4, r4, -4
0:
lwzu r0,4(r3)
stwu r0,4(r4)
bdnz 0b /* copy loop */
blrl
#endif
/*
* Calculate absolute address in FLASH and jump there
*----------------------------------------------------------------------*/
lis r3, CFG_MONITOR_BASE@h
ori r3, r3, CFG_MONITOR_BASE@l
addi r3, r3, in_flash - _start + EXC_OFF_SYS_RESET
mtlr r3
blr
in_flash:
/* Initialize some SPRs that are hard to access from C */
/*----------------------------------------------------------------------*/
lis r3, CFG_IMMR@h /* Pass IMMR as arg1 to C routine */
lis r2, CFG_INIT_SP_ADDR@h
ori r1, r2, CFG_INIT_SP_ADDR@l /* Set up the stack in internal SRAM */
/* Note: R0 is still 0 here */
stwu r0, -4(r1) /* Clear final stack frame so that */
stwu r0, -4(r1) /* stack backtraces terminate cleanly */
/*
* Disable serialized ifetch and show cycles
* (i.e. set processor to normal mode) for maximum
* performance.
*/
li r2, 0x0007
mtspr ICTRL, r2
/* Set up debug mode entry */
lis r2, CFG_DER@h
ori r2, r2, CFG_DER@l
mtspr DER, r2
/* Let the C-code set up the rest */
/* */
/* Be careful to keep code relocatable ! */
/*----------------------------------------------------------------------*/
GET_GOT /* initialize GOT access */
/* r3: IMMR */
bl cpu_init_f /* run low-level CPU init code (from Flash) */
mr r3, r21
/* r3: BOOTFLAG */
bl board_init_f /* run 1st part of board init code (from Flash) */
.globl _start_of_vectors
_start_of_vectors:
/* Machine check */
STD_EXCEPTION(0x200, MachineCheck, MachineCheckException)
/* Data Storage exception. "Never" generated on the 860. */
STD_EXCEPTION(0x300, DataStorage, UnknownException)
/* Instruction Storage exception. "Never" generated on the 860. */
STD_EXCEPTION(0x400, InstStorage, UnknownException)
/* External Interrupt exception. */
STD_EXCEPTION(0x500, ExtInterrupt, external_interrupt)
/* Alignment exception. */
. = 0x600
Alignment:
EXCEPTION_PROLOG(SRR0, SRR1)
mfspr r4,DAR
stw r4,_DAR(r21)
mfspr r5,DSISR
stw r5,_DSISR(r21)
addi r3,r1,STACK_FRAME_OVERHEAD
li r20,MSR_KERNEL
rlwimi r20,r23,0,16,16 /* copy EE bit from saved MSR */
lwz r6,GOT(transfer_to_handler)
mtlr r6
blrl
.L_Alignment:
.long AlignmentException - _start + EXC_OFF_SYS_RESET
.long int_return - _start + EXC_OFF_SYS_RESET
/* Program check exception */
. = 0x700
ProgramCheck:
EXCEPTION_PROLOG(SRR0, SRR1)
addi r3,r1,STACK_FRAME_OVERHEAD
li r20,MSR_KERNEL
rlwimi r20,r23,0,16,16 /* copy EE bit from saved MSR */
lwz r6,GOT(transfer_to_handler)
mtlr r6
blrl
.L_ProgramCheck:
.long ProgramCheckException - _start + EXC_OFF_SYS_RESET
.long int_return - _start + EXC_OFF_SYS_RESET
/* FPU on MPC5xx available. We will use it later.
*/
STD_EXCEPTION(0x800, FPUnavailable, UnknownException)
/* I guess we could implement decrementer, and may have
* to someday for timekeeping.
*/
STD_EXCEPTION(0x900, Decrementer, timer_interrupt)
STD_EXCEPTION(0xa00, Trap_0a, UnknownException)
STD_EXCEPTION(0xb00, Trap_0b, UnknownException)
STD_EXCEPTION(0xc00, SystemCall, UnknownException)
STD_EXCEPTION(0xd00, SingleStep, UnknownException)
STD_EXCEPTION(0xe00, Trap_0e, UnknownException)
STD_EXCEPTION(0xf00, Trap_0f, UnknownException)
/* On the MPC8xx, this is a software emulation interrupt. It occurs
* for all unimplemented and illegal instructions.
*/
STD_EXCEPTION(0x1000, SoftEmu, SoftEmuException)
STD_EXCEPTION(0x1100, InstructionTLBMiss, UnknownException)
STD_EXCEPTION(0x1200, DataTLBMiss, UnknownException)
STD_EXCEPTION(0x1300, InstructionTLBError, UnknownException)
STD_EXCEPTION(0x1400, DataTLBError, UnknownException)
STD_EXCEPTION(0x1500, Reserved5, UnknownException)
STD_EXCEPTION(0x1600, Reserved6, UnknownException)
STD_EXCEPTION(0x1700, Reserved7, UnknownException)
STD_EXCEPTION(0x1800, Reserved8, UnknownException)
STD_EXCEPTION(0x1900, Reserved9, UnknownException)
STD_EXCEPTION(0x1a00, ReservedA, UnknownException)
STD_EXCEPTION(0x1b00, ReservedB, UnknownException)
STD_EXCEPTION(0x1c00, DataBreakpoint, UnknownException)
STD_EXCEPTION(0x1d00, InstructionBreakpoint, DebugException)
STD_EXCEPTION(0x1e00, PeripheralBreakpoint, UnknownException)
STD_EXCEPTION(0x1f00, DevPortBreakpoint, UnknownException)
.globl _end_of_vectors
_end_of_vectors:
. = 0x2000
/*
* This code finishes saving the registers to the exception frame
* and jumps to the appropriate handler for the exception.
* Register r21 is pointer into trap frame, r1 has new stack pointer.
*/
.globl transfer_to_handler
transfer_to_handler:
stw r22,_NIP(r21)
lis r22,MSR_POW@h
andc r23,r23,r22
stw r23,_MSR(r21)
SAVE_GPR(7, r21)
SAVE_4GPRS(8, r21)
SAVE_8GPRS(12, r21)
SAVE_8GPRS(24, r21)
mflr r23
andi. r24,r23,0x3f00 /* get vector offset */
stw r24,TRAP(r21)
li r22,0
stw r22,RESULT(r21)
mtspr SPRG2,r22 /* r1 is now kernel sp */
lwz r24,0(r23) /* virtual address of handler */
lwz r23,4(r23) /* where to go when done */
mtspr SRR0,r24
mtspr SRR1,r20
mtlr r23
SYNC
rfi /* jump to handler, enable MMU */
int_return:
mfmsr r28 /* Disable interrupts */
li r4,0
ori r4,r4,MSR_EE
andc r28,r28,r4
SYNC /* Some chip revs need this... */
mtmsr r28
SYNC
lwz r2,_CTR(r1)
lwz r0,_LINK(r1)
mtctr r2
mtlr r0
lwz r2,_XER(r1)
lwz r0,_CCR(r1)
mtspr XER,r2
mtcrf 0xFF,r0
REST_10GPRS(3, r1)
REST_10GPRS(13, r1)
REST_8GPRS(23, r1)
REST_GPR(31, r1)
lwz r2,_NIP(r1) /* Restore environment */
lwz r0,_MSR(r1)
mtspr SRR0,r2
mtspr SRR1,r0
lwz r0,GPR0(r1)
lwz r2,GPR2(r1)
lwz r1,GPR1(r1)
SYNC
rfi
/*
* unsigned int get_immr (unsigned int mask)
*
* return (mask ? (IMMR & mask) : IMMR);
*/
.globl get_immr
get_immr:
mr r4,r3 /* save mask */
mfspr r3, IMMR /* IMMR */
cmpwi 0,r4,0 /* mask != 0 ? */
beq 4f
and r3,r3,r4 /* IMMR & mask */
4:
blr
.globl get_pvr
get_pvr:
mfspr r3, PVR
blr
/*------------------------------------------------------------------------------*/
/*
* void relocate_code (addr_sp, gd, addr_moni)
*
* This "function" does not return, instead it continues in RAM
* after relocating the monitor code.
*
* r3 = dest
* r4 = src
* r5 = length in bytes
* r6 = cachelinesize
*/
.globl relocate_code
relocate_code:
mr r1, r3 /* Set new stack pointer in SRAM */
mr r9, r4 /* Save copy of global data pointer in SRAM */
mr r10, r5 /* Save copy of monitor destination Address in SRAM */
mr r3, r5 /* Destination Address */
lis r4, CFG_MONITOR_BASE@h /* Source Address */
ori r4, r4, CFG_MONITOR_BASE@l
lwz r5, GOT(__init_end)
sub r5, r5, r4
/*
* Fix GOT pointer:
*
* New GOT-PTR = (old GOT-PTR - CFG_MONITOR_BASE) + Destination Address
*
* Offset:
*/
sub r15, r10, r4
/* First our own GOT */
add r14, r14, r15
/* the the one used by the C code */
add r30, r30, r15
/*
* Now relocate code
*/
cmplw cr1,r3,r4
addi r0,r5,3
srwi. r0,r0,2
beq cr1,4f /* In place copy is not necessary */
beq 4f /* Protect against 0 count */
mtctr r0
bge cr1,2f
la r8,-4(r4)
la r7,-4(r3)
1: lwzu r0,4(r8)
stwu r0,4(r7)
bdnz 1b
b 4f
2: slwi r0,r0,2
add r8,r4,r0
add r7,r3,r0
3: lwzu r0,-4(r8)
stwu r0,-4(r7)
bdnz 3b
4: sync
isync
/*
* We are done. Do not return, instead branch to second part of board
* initialization, now running from RAM.
*/
addi r0, r10, in_ram - _start + EXC_OFF_SYS_RESET
mtlr r0
blr
in_ram:
/*
* Relocation Function, r14 point to got2+0x8000
*
* Adjust got2 pointers, no need to check for 0, this code
* already puts a few entries in the table.
*/
li r0,__got2_entries@sectoff@l
la r3,GOT(_GOT2_TABLE_)
lwz r11,GOT(_GOT2_TABLE_)
mtctr r0
sub r11,r3,r11
addi r3,r3,-4
1: lwzu r0,4(r3)
add r0,r0,r11
stw r0,0(r3)
bdnz 1b
/*
* Now adjust the fixups and the pointers to the fixups
* in case we need to move ourselves again.
*/
2: li r0,__fixup_entries@sectoff@l
lwz r3,GOT(_FIXUP_TABLE_)
cmpwi r0,0
mtctr r0
addi r3,r3,-4
beq 4f
3: lwzu r4,4(r3)
lwzux r0,r4,r11
add r0,r0,r11
stw r10,0(r3)
stw r0,0(r4)
bdnz 3b
4:
clear_bss:
/*
* Now clear BSS segment
*/
lwz r3,GOT(__bss_start)
lwz r4,GOT(_end)
cmplw 0, r3, r4
beq 6f
li r0, 0
5:
stw r0, 0(r3)
addi r3, r3, 4
cmplw 0, r3, r4
bne 5b
6:
mr r3, r9 /* Global Data pointer */
mr r4, r10 /* Destination Address */
bl board_init_r
/*
* Copy exception vector code to low memory
*
* r3: dest_addr
* r7: source address, r8: end address, r9: target address
*/
.globl trap_init
trap_init:
lwz r7, GOT(_start)
lwz r8, GOT(_end_of_vectors)
li r9, 0x100 /* reset vector always at 0x100 */
cmplw 0, r7, r8
bgelr /* return if r7>=r8 - just in case */
mflr r4 /* save link register */
1:
lwz r0, 0(r7)
stw r0, 0(r9)
addi r7, r7, 4
addi r9, r9, 4
cmplw 0, r7, r8
bne 1b
/*
* relocate `hdlr' and `int_return' entries
*/
li r7, .L_MachineCheck - _start + EXC_OFF_SYS_RESET
li r8, Alignment - _start + EXC_OFF_SYS_RESET
2:
bl trap_reloc
addi r7, r7, 0x100 /* next exception vector */
cmplw 0, r7, r8
blt 2b
li r7, .L_Alignment - _start + EXC_OFF_SYS_RESET
bl trap_reloc
li r7, .L_ProgramCheck - _start + EXC_OFF_SYS_RESET
bl trap_reloc
li r7, .L_FPUnavailable - _start + EXC_OFF_SYS_RESET
li r8, SystemCall - _start + EXC_OFF_SYS_RESET
3:
bl trap_reloc
addi r7, r7, 0x100 /* next exception vector */
cmplw 0, r7, r8
blt 3b
li r7, .L_SingleStep - _start + EXC_OFF_SYS_RESET
li r8, _end_of_vectors - _start + EXC_OFF_SYS_RESET
4:
bl trap_reloc
addi r7, r7, 0x100 /* next exception vector */
cmplw 0, r7, r8
blt 4b
mtlr r4 /* restore link register */
blr
/*
* Function: relocate entries for one exception vector
*/
trap_reloc:
lwz r0, 0(r7) /* hdlr ... */
add r0, r0, r3 /* ... += dest_addr */
stw r0, 0(r7)
lwz r0, 4(r7) /* int_return ... */
add r0, r0, r3 /* ... += dest_addr */
stw r0, 4(r7)
sync
isync
blr
#if defined(CONFIG_PATI)
/* Program the PLL */
pll_prog_code_start:
lis r4, (CFG_IMMR + 0x002fc384)@h
ori r4, r4, (CFG_IMMR + 0x002fc384)@l
lis r3, (0x55ccaa33)@h
ori r3, r3, (0x55ccaa33)@l
stw r3, 0(r4)
lis r4, (CFG_IMMR + 0x002fc284)@h
ori r4, r4, (CFG_IMMR + 0x002fc284)@l
lis r3, CFG_PLPRCR@h
ori r3, r3, CFG_PLPRCR@l
stw r3, 0(r4)
addis r3,0,0x0
ori r3,r3,0xA000
mtctr r3
..spinlp:
bdnz ..spinlp /* spin loop */
blr
pll_prog_code_end:
nop
blr
#endif
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