u-boot/cpu/mpc83xx/start.S

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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 2004 Freescale Semiconductor, Inc.
*
* 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
*/
/*
* U-Boot - Startup Code for MPC83xx PowerPC based Embedded Boards
*/
#include <config.h>
#include <mpc83xx.h>
#include <version.h>
#define CONFIG_83XX 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 <asm/cache.h>
#include <asm/mmu.h>
#ifndef CONFIG_IDENT_STRING
#define CONFIG_IDENT_STRING "MPC83XX"
#endif
/* We don't want the MMU yet.
*/
#undef MSR_KERNEL
/*
* Floating Point enable, Machine Check and Recoverable Interr.
*/
#ifdef DEBUG
#define MSR_KERNEL (MSR_FP|MSR_RI)
#else
#define MSR_KERNEL (MSR_FP|MSR_ME|MSR_RI)
#endif
/*
* 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
/*
* Version string - must be in data segment because MPC83xx uses the
* first 256 bytes for the Hard Reset Configuration Word table (see
* below). Similarly, can't have the U-Boot Magic Number as the first
* thing in the image - don't know how this will affect the image tools,
* but I guess I'll find out soon.
*/
.data
.globl version_string
version_string:
.ascii U_BOOT_VERSION
.ascii " (", __DATE__, " - ", __TIME__, ")"
.ascii " ", CONFIG_IDENT_STRING, "\0"
.text
#define _HRCW_TABLE_ENTRY(w) \
.fill 8,1,(((w)>>24)&0xff); \
.fill 8,1,(((w)>>16)&0xff); \
.fill 8,1,(((w)>> 8)&0xff); \
.fill 8,1,(((w) )&0xff)
_HRCW_TABLE_ENTRY(CFG_HRCW_LOW)
_HRCW_TABLE_ENTRY(CFG_HRCW_HIGH)
#ifndef CONFIG_DEFAULT_IMMR
#error CONFIG_DEFAULT_IMMR must be defined
#endif /* CFG_DEFAULT_IMMR */
#ifndef CFG_IMMRBAR
#define CFG_IMMRBAR CONFIG_DEFAULT_IMMR
#endif /* CFG_IMMRBAR */
/*
* After configuration, a system reset exception is executed using the
* vector at offset 0x100 relative to the base set by MSR[IP]. If
* MSR[IP] is 0, the base address is 0x00000000. If MSR[IP] is 1, the
* base address is 0xfff00000. In the case of a Power On Reset or Hard
* Reset, the value of MSR[IP] is determined by the CIP field in the
* HRCW.
*
* Other bits in the HRCW set up the Base Address and Port Size in BR0.
* This determines the location of the boot ROM (flash or EPROM) in the
* processor's address space at boot time. As long as the HRCW is set up
* so that we eventually end up executing the code below when the
* processor executes the reset exception, the actual values used should
* not matter.
*
* Once we have got here, the address mask in OR0 is cleared so that the
* bottom 32K of the boot ROM is effectively repeated all throughout the
* processor's address space, after which we can jump to the absolute
* address at which the boot ROM was linked at compile time, and proceed
* to initialise the memory controller without worrying if the rug will
* be pulled out from under us, so to speak (it will be fine as long as
* we configure BR0 with the same boot ROM link address).
*/
. = EXC_OFF_SYS_RESET
.globl _start
_start: /* time t 0 */
li r21, BOOTFLAG_COLD /* Normal Power-On: Boot from FLASH*/
nop
b boot_cold
. = EXC_OFF_SYS_RESET + 0x10
.globl _start_warm
_start_warm:
li r21, BOOTFLAG_WARM /* Software reboot */
b boot_warm
boot_cold: /* time t 3 */
lis r4, CONFIG_DEFAULT_IMMR@h
nop
boot_warm: /* time t 5 */
mfmsr r5 /* save msr contents */
lis r3, CFG_IMMRBAR@h
ori r3, r3, CFG_IMMRBAR@l
stw r3, IMMRBAR(r4)
/* Initialise the E300 processor core */
/*------------------------------------------*/
bl init_e300_core
#ifndef CFG_RAMBOOT
/* Inflate flash location so it appears everywhere, calculate */
/* the absolute address in final location of the FLASH, jump */
/* there and deflate the flash size back to minimal size */
/*------------------------------------------------------------*/
bl map_flash_by_law1
lis r4, (CFG_MONITOR_BASE)@h
ori r4, r4, (CFG_MONITOR_BASE)@l
addi r5, r4, in_flash - _start + EXC_OFF_SYS_RESET
mtlr r5
blr
in_flash:
#if 1 /* Remapping flash with LAW0. */
bl remap_flash_by_law0
#endif
#endif /* CFG_RAMBOOT */
bl setup_stack_in_data_cache_on_r1
/* let the C-code set up the rest */
/* */
/* Be careful to keep code relocatable & stack humble */
/*------------------------------------------------------*/
GET_GOT /* initialize GOT access */
/* r3: IMMR */
lis r3, CFG_IMMRBAR@h
/* run low-level CPU init code (in Flash)*/
bl cpu_init_f
/* r3: BOOTFLAG */
mr r3, r21
/* run 1st part of board init code (in Flash)*/
bl board_init_f
/*
* Vector Table
*/
.globl _start_of_vectors
_start_of_vectors:
/* Machine check */
STD_EXCEPTION(0x200, MachineCheck, MachineCheckException)
/* Data Storage exception. */
STD_EXCEPTION(0x300, DataStorage, UnknownException)
/* Instruction Storage exception. */
STD_EXCEPTION(0x400, InstStorage, UnknownException)
/* External Interrupt exception. */
#ifndef FIXME
STD_EXCEPTION(0x500, ExtInterrupt, external_interrupt)
#endif
/* Alignment exception. */
. = 0x600
Alignment:
EXCEPTION_PROLOG
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 */
rlwimi r20,r23,0,25,25 /* copy IP 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
addi r3,r1,STACK_FRAME_OVERHEAD
li r20,MSR_KERNEL
rlwimi r20,r23,0,16,16 /* copy EE bit from saved MSR */
rlwimi r20,r23,0,25,25 /* copy IP 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
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)
STD_EXCEPTION(0x1000, InstructionTLBMiss, UnknownException)
STD_EXCEPTION(0x1100, DataLoadTLBMiss, UnknownException)
STD_EXCEPTION(0x1200, DataStoreTLBMiss, UnknownException)
#ifdef DEBUG
. = 0x1300
/*
* This exception occurs when the program counter matches the
* Instruction Address Breakpoint Register (IABR).
*
* I want the cpu to halt if this occurs so I can hunt around
* with the debugger and look at things.
*
* When DEBUG is defined, both machine check enable (in the MSR)
* and checkstop reset enable (in the reset mode register) are
* turned off and so a checkstop condition will result in the cpu
* halting.
*
* I force the cpu into a checkstop condition by putting an illegal
* instruction here (at least this is the theory).
*
* well - that didnt work, so just do an infinite loop!
*/
1: b 1b
#else
STD_EXCEPTION(0x1300, InstructionBreakpoint, DebugException)
#endif
STD_EXCEPTION(0x1400, SMI, UnknownException)
STD_EXCEPTION(0x1500, Trap_15, UnknownException)
STD_EXCEPTION(0x1600, Trap_16, UnknownException)
STD_EXCEPTION(0x1700, Trap_17, UnknownException)
STD_EXCEPTION(0x1800, Trap_18, UnknownException)
STD_EXCEPTION(0x1900, Trap_19, UnknownException)
STD_EXCEPTION(0x1a00, Trap_1a, UnknownException)
STD_EXCEPTION(0x1b00, Trap_1b, UnknownException)
STD_EXCEPTION(0x1c00, Trap_1c, UnknownException)
STD_EXCEPTION(0x1d00, Trap_1d, UnknownException)
STD_EXCEPTION(0x1e00, Trap_1e, UnknownException)
STD_EXCEPTION(0x1f00, Trap_1f, UnknownException)
STD_EXCEPTION(0x2000, Trap_20, UnknownException)
STD_EXCEPTION(0x2100, Trap_21, UnknownException)
STD_EXCEPTION(0x2200, Trap_22, UnknownException)
STD_EXCEPTION(0x2300, Trap_23, UnknownException)
STD_EXCEPTION(0x2400, Trap_24, UnknownException)
STD_EXCEPTION(0x2500, Trap_25, UnknownException)
STD_EXCEPTION(0x2600, Trap_26, UnknownException)
STD_EXCEPTION(0x2700, Trap_27, UnknownException)
STD_EXCEPTION(0x2800, Trap_28, UnknownException)
STD_EXCEPTION(0x2900, Trap_29, UnknownException)
STD_EXCEPTION(0x2a00, Trap_2a, UnknownException)
STD_EXCEPTION(0x2b00, Trap_2b, UnknownException)
STD_EXCEPTION(0x2c00, Trap_2c, UnknownException)
STD_EXCEPTION(0x2d00, Trap_2d, UnknownException)
STD_EXCEPTION(0x2e00, Trap_2e, UnknownException)
STD_EXCEPTION(0x2f00, Trap_2f, UnknownException)
.globl _end_of_vectors
_end_of_vectors:
. = 0x3000
/*
* 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)
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
/*
* This code initialises the E300 processor core
* (conforms to PowerPC 603e spec)
* Note: expects original MSR contents to be in r5.
*/
.globl init_e300_core
init_e300_core: /* time t 10 */
/* Initialize machine status; enable machine check interrupt */
/*-----------------------------------------------------------*/
li r3, MSR_KERNEL /* Set ME and RI flags */
rlwimi r3, r5, 0, 25, 25 /* preserve IP bit set by HRCW */
#ifdef DEBUG
rlwimi r3, r5, 0, 21, 22 /* debugger might set SE & BE bits */
#endif
SYNC /* Some chip revs need this... */
mtmsr r3
SYNC
mtspr SRR1, r3 /* Make SRR1 match MSR */
lis r3, CFG_IMMRBAR@h
#if defined(CONFIG_WATCHDOG)
/* Initialise the Wathcdog values and reset it (if req) */
/*------------------------------------------------------*/
lis r4, CFG_WATCHDOG_VALUE
ori r4, r4, (SWCRR_SWEN | SWCRR_SWRI | SWCRR_SWPR)
stw r4, SWCRR(r3)
/* and reset it */
li r4, 0x556C
sth r4, SWSRR@l(r3)
li r4, 0xAA39
sth r4, SWSRR@l(r3)
#else
/* Disable Wathcdog */
/*-------------------*/
xor r4, r4, r4
stw r4, SWCRR(r3)
#endif /* CONFIG_WATCHDOG */
/* Initialize the Hardware Implementation-dependent Registers */
/* HID0 also contains cache control */
/*------------------------------------------------------*/
lis r3, CFG_HID0_INIT@h
ori r3, r3, CFG_HID0_INIT@l
SYNC
mtspr HID0, r3
lis r3, CFG_HID0_FINAL@h
ori r3, r3, CFG_HID0_FINAL@l
SYNC
mtspr HID0, r3
lis r3, CFG_HID2@h
ori r3, r3, CFG_HID2@l
SYNC
mtspr HID2, r3
/* clear all BAT's */
/*----------------------------------*/
xor r0, r0, r0
mtspr DBAT0U, r0
mtspr DBAT0L, r0
mtspr DBAT1U, r0
mtspr DBAT1L, r0
mtspr DBAT2U, r0
mtspr DBAT2L, r0
mtspr DBAT3U, r0
mtspr DBAT3L, r0
mtspr IBAT0U, r0
mtspr IBAT0L, r0
mtspr IBAT1U, r0
mtspr IBAT1L, r0
mtspr IBAT2U, r0
mtspr IBAT2L, r0
mtspr IBAT3U, r0
mtspr IBAT3L, r0
SYNC
/* invalidate all tlb's
*
* From the 603e User Manual: "The 603e provides the ability to
* invalidate a TLB entry. The TLB Invalidate Entry (tlbie)
* instruction invalidates the TLB entry indexed by the EA, and
* operates on both the instruction and data TLBs simultaneously
* invalidating four TLB entries (both sets in each TLB). The
* index corresponds to bits 15-19 of the EA. To invalidate all
* entries within both TLBs, 32 tlbie instructions should be
* issued, incrementing this field by one each time."
*
* "Note that the tlbia instruction is not implemented on the
* 603e."
*
* bits 15-19 correspond to addresses 0x00000000 to 0x0001F000
* incrementing by 0x1000 each time. The code below is sort of
* based on code in "flush_tlbs" from arch/ppc/kernel/head.S
*
*/
li r3, 32
mtctr r3
li r3, 0
1: tlbie r3
addi r3, r3, 0x1000
bdnz 1b
SYNC
/* Done! */
/*------------------------------*/
blr
/* Cache functions.
*
* Note: requires that all cache bits in
* HID0 are in the low half word.
*/
.globl icache_enable
icache_enable:
mfspr r3, HID0
ori r3, r3, HID0_ICE
lis r4, 0
ori r4, r4, HID0_ILOCK
andc r3, r3, r4
ori r4, r3, HID0_ICFI
isync
mtspr HID0, r4 /* sets enable and invalidate, clears lock */
isync
mtspr HID0, r3 /* clears invalidate */
blr
.globl icache_disable
icache_disable:
mfspr r3, HID0
lis r4, 0
ori r4, r4, HID0_ICE|HID0_ILOCK
andc r3, r3, r4
ori r4, r3, HID0_ICFI
isync
mtspr HID0, r4 /* sets invalidate, clears enable and lock*/
isync
mtspr HID0, r3 /* clears invalidate */
blr
.globl icache_status
icache_status:
mfspr r3, HID0
rlwinm r3, r3, HID0_ICE_SHIFT, 31, 31
blr
.globl dcache_enable
dcache_enable:
mfspr r3, HID0
ori r3, r3, HID0_ENABLE_DATA_CACHE
lis r4, 0
ori r4, r4, HID0_LOCK_DATA_CACHE
andc r3, r3, r4
ori r4, r3, HID0_LOCK_INSTRUCTION_CACHE
sync
mtspr HID0, r4 /* sets enable and invalidate, clears lock */
sync
mtspr HID0, r3 /* clears invalidate */
blr
.globl dcache_disable
dcache_disable:
mfspr r3, HID0
lis r4, 0
ori r4, r4, HID0_ENABLE_DATA_CACHE|HID0_LOCK_DATA_CACHE
andc r3, r3, r4
ori r4, r3, HID0_INVALIDATE_DATA_CACHE
sync
mtspr HID0, r4 /* sets invalidate, clears enable and lock */
sync
mtspr HID0, r3 /* clears invalidate */
blr
.globl dcache_status
dcache_status:
mfspr r3, HID0
rlwinm r3, r3, HID0_DCE_SHIFT, 31, 31
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 */
mr r9, r4 /* Save copy of Global Data pointer */
mr r10, r5 /* Save copy of Destination Address */
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
li r6, CFG_CACHELINE_SIZE /* Cache Line Size */
/*
* 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
/* then 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 7f /* Protect against 0 count */
mtctr r0
bge cr1,2f
la r8,-4(r4)
la r7,-4(r3)
/* copy */
1: lwzu r0,4(r8)
stwu r0,4(r7)
bdnz 1b
addi r0,r5,3
srwi. r0,r0,2
mtctr r0
la r8,-4(r4)
la r7,-4(r3)
/* and compare */
20: lwzu r20,4(r8)
lwzu r21,4(r7)
xor. r22, r20, r21
bne 30f
bdnz 20b
b 4f
/* compare failed */
30: li r3, 0
blr
2: slwi r0,r0,2 /* re copy in reverse order ... y do we needed it? */
add r8,r4,r0
add r7,r3,r0
3: lwzu r0,-4(r8)
stwu r0,-4(r7)
bdnz 3b
/*
* Now flush the cache: note that we must start from a cache aligned
* address. Otherwise we might miss one cache line.
*/
4:
bl un_setup_stack_in_data_cache
mr r7, r3
mr r8, r4
bl dcache_disable
mr r3, r7
mr r4, r8
cmpwi r6,0
add r5,r3,r5
beq 7f /* Always flush prefetch queue in any case */
subi r0,r6,1
andc r3,r3,r0
mfspr r7,HID0 /* don't do dcbst if dcache is disabled*/
rlwinm r7,r7,HID0_DCE_SHIFT,31,31
cmpwi r7,0
beq 9f
mr r4,r3
5: dcbst 0,r4
add r4,r4,r6
cmplw r4,r5
blt 5b
sync /* Wait for all dcbst to complete on bus */
9: mfspr r7,HID0 /* don't do icbi if icache is disabled */
rlwinm r7,r7,HID0_DCE_SHIFT,31,31
cmpwi r7,0
beq 7f
mr r4,r3
6: icbi 0,r4
add r4,r4,r6
cmplw r4,r5
blt 6b
7: sync /* Wait for all icbi to complete on bus */
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)
#if defined(CONFIG_HYMOD)
/*
* For HYMOD - the environment is the very last item in flash.
* The real .bss stops just before environment starts, so only
* clear up to that point.
*
* taken from mods for FADS board
*/
lwz r4,GOT(environment)
#else
lwz r4,GOT(_end)
#endif
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
mfmsr r3 /* now that the vectors have */
lis r7, MSR_IP@h /* relocated into low memory */
ori r7, r7, MSR_IP@l /* MSR[IP] can be turned off */
andc r3, r3, r7 /* (if it was on) */
SYNC /* Some chip revs need this... */
mtmsr r3
SYNC
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)
blr
#ifdef CFG_INIT_RAM_LOCK
.globl unlock_ram_in_cache
unlock_ram_in_cache:
/* invalidate the INIT_RAM section */
lis r3, (CFG_INIT_RAM_ADDR & ~31)@h
ori r3, r3, (CFG_INIT_RAM_ADDR & ~31)@l
li r2,512
mtctr r2
1: icbi r0, r3
dcbi r0, r3
addi r3, r3, 32
bdnz 1b
sync /* Wait for all icbi to complete on bus */
isync
blr
#endif
map_flash_by_law1:
/* When booting from ROM (Flash or EPROM), clear the */
/* Address Mask in OR0 so ROM appears everywhere */
/*----------------------------------------------------*/
lis r3, (CFG_IMMRBAR)@h /* r3 <= CFG_IMMRBAR */
lwz r4, OR0@l(r3)
li r5, 0x7fff /* r5 <= 0x00007FFFF */
and r4, r4, r5
stw r4, OR0@l(r3) /* OR0 <= OR0 & 0x00007FFFF */
/* As MPC8349E User's Manual presented, when RCW[BMS] is set to 0,
* system will boot from 0x0000_0100, and the LBLAWBAR0[BASE_ADDR]
* reset value is 0x00000; when RCW[BMS] is set to 1, system will boot
* from 0xFFF0_0100, and the LBLAWBAR0[BASE_ADDR] reset value is
* 0xFF800. From the hard resetting to here, the processor fetched and
* executed the instructions one by one. There is not absolutely
* jumping happened. Laterly, the u-boot code has to do an absolutely
* jumping to tell the CPU instruction fetching component what the
* u-boot TEXT base address is. Because the TEXT base resides in the
* boot ROM memory space, to garantee the code can run smoothly after
* that jumping, we must map in the entire boot ROM by Local Access
* Window. Sometimes, we desire an non-0x00000 or non-0xFF800 starting
* address for boot ROM, such as 0xFE000000. In this case, the default
* LBIU Local Access Widow 0 will not cover this memory space. So, we
* need another window to map in it.
*/
lis r4, (CFG_FLASH_BASE)@h
ori r4, r4, (CFG_FLASH_BASE)@l
stw r4, LBLAWBAR1(r3) /* LBLAWBAR1 <= CFG_FLASH_BASE */
lis r4, (0x80000016)@h
ori r4, r4, (0x80000016)@l
stw r4, LBLAWAR1(r3) /* LBLAWAR1 <= 8MB Flash Size */
blr
/* Though all the LBIU Local Access Windows and LBC Banks will be
* initialized in the C code, we'd better configure boot ROM's
* window 0 and bank 0 correctly at here.
*/
remap_flash_by_law0:
/* Initialize the BR0 with the boot ROM starting address. */
lwz r4, BR0(r3)
li r5, 0x7FFF
and r4, r4, r5
lis r5, (CFG_FLASH_BASE & 0xFFFF8000)@h
ori r5, r5, (CFG_FLASH_BASE & 0xFFFF8000)@l
or r5, r5, r4
stw r5, BR0(r3) /* r5 <= (CFG_FLASH_BASE & 0xFFFF8000) | (BR0 & 0x00007FFF) */
lwz r4, OR0(r3)
lis r5, 0xFF80 /* 8M */
or r4, r4, r5
stw r4, OR0(r3) /* OR0 <= OR0 | 0xFF800000 */
lis r4, (CFG_FLASH_BASE)@h
ori r4, r4, (CFG_FLASH_BASE)@l
stw r4, LBLAWBAR0(r3) /* LBLAWBAR0 <= CFG_FLASH_BASE */
lis r4, (0x80000016)@h
ori r4, r4, (0x80000016)@l
stw r4, LBLAWAR0(r3) /* LBLAWAR0 <= 8MB Flash Size */
xor r4, r4, r4
stw r4, LBLAWBAR1(r3)
stw r4, LBLAWAR1(r3) /* Off LBIU LAW1 */
blr
setup_stack_in_data_cache_on_r1:
lis r3, (CFG_IMMRBAR)@h
/* setup D-BAT for the D-Cache (with out real memory backup) */
lis r4, (CFG_INIT_RAM_ADDR & 0xFFFE0000)@h
mtspr DBAT0U, r4
ori r4, r4, 0x0002
mtspr DBAT0L, r4
isync
#if 0
/* Enable MMU */
mfmsr r4
ori r4, r4, (MSR_DR | MSR_IR)@l
mtmsr r4
#endif
/* Enable and invalidate data cache. */
mfspr r4, HID0
mr r5, r4
ori r4, r4, HID0_DCE | HID0_DCI
ori r5, r5, HID0_DCE
sync
mtspr HID0, r4
mtspr HID0, r5
sync
/* Allocate Initial RAM in data cache.*/
li r0, 0
lis r4, (CFG_INIT_RAM_ADDR)@h
ori r4, r4, (CFG_INIT_RAM_ADDR)@l
li r5, 128*8 /* 128*8*32=32Kb */
mtctr r5
1:
dcbz r0, r4
addi r4, r4, 32
bdnz 1b
isync
/* Lock all the D-cache, basically leaving the reset of the program without dcache */
mfspr r4, HID0
ori r4, r4, (HID0_DLOCK)@l
sync
mtspr HID0 , r4
/* setup the stack pointer in r1 */
lis r1, (CFG_INIT_RAM_ADDR + CFG_GBL_DATA_OFFSET)@h
ori r1, r1, (CFG_INIT_RAM_ADDR + CFG_GBL_DATA_OFFSET)@l
li r0, 0 /* Make room for stack frame header and */
stwu r0, -4(r1) /* clear final stack frame so that */
stwu r0, -4(r1) /* stack backtraces terminate cleanly */
blr
un_setup_stack_in_data_cache:
blr
mr r14, r4
mr r15, r5
lis r4, (CFG_INIT_RAM_ADDR & 0xFFFE0000)@h
mtspr DBAT0U, r4
ori r4, r4, 0x0002
mtspr DBAT0L, r4
isync
/* un lock all the D-cache */
mfspr r4, HID0
lis r5, (~(HID0_DLOCK))@h
ori r5, r5, (~(HID0_DLOCK))@l
and r4, r4, r5
sync
mtspr HID0 , r4
/* Re - Allocate Initial RAM in data cache.*/
li r0, 0
lis r4, (CFG_INIT_RAM_ADDR)@h
ori r4, r4, (CFG_INIT_RAM_ADDR)@l
li r5, 128*8 /* 128*8*32=32Kb */
mtctr r5
1:
dcbz r0, r4
addi r4, r4, 32
bdnz 1b
isync
mflr r16
bl dcache_disable
mtlr r16
blr
#if 0
#define GREEN_LIGHT 0x2B0D4046
#define RED_LIGHT 0x250D4046
#define LIB_CNT 0x4FFF
/*
* Lib Light
*/
.globl liblight
liblight:
lis r3, CFG_IMMRBAR@h
ori r3, r3, CFG_IMMRBAR@l
li r4, 0x3002
mtmsr r4
xor r4, r4, r4
mtspr HID0, r4
mtspr HID2, r4
lis r4, 0xF8000000@h
ori r4, r4, 0xF8000000@l
stw r4, LBLAWBAR1(r3)
lis r4, 0x8000000E@h
ori r4, r4, 0x8000000E@l
stw r4, LBLAWAR1(r3)
lis r4, 0xF8000801@h
ori r4, r4, 0xF8000801@l
stw r4, BR1(r3)
lis r4, 0xFFFFE8f0@h
ori r4, r4, 0xFFFFE8f0@l
stw r4, OR1(r3)
lis r4, 0xF8000000@h
ori r4, r4, 0xF8000000@l
lis r5, GREEN_LIGHT@h
ori r5, r5, GREEN_LIGHT@l
lis r6, RED_LIGHT@h
ori r6, r6, RED_LIGHT@l
lis r7, LIB_CNT@h
ori r7, r7, LIB_CNT@l
1:
stw r5, 0(r4)
mtctr r7
2: bdnz 2b
stw r6, 0(r4)
mtctr r7
3: bdnz 3b
b 1b
#endif