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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 - 2003 Wolfgang Denk <wd@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
+ */
+
+/*
+ * U-Boot - Startup Code for MPC8220 CPUs
+ */
+#include <config.h>
+#include <mpc8220.h>
+#include <timestamp.h>
+#include <version.h>
+
+#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 ""
+#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 r12 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
+ */
+ .data
+ .globl version_string
+version_string:
+ .ascii U_BOOT_VERSION
+ .ascii " (", U_BOOT_DATE, " - ", U_BOOT_TIME, ")"
+ .ascii CONFIG_IDENT_STRING, "\0"
+
+/*
+ * Exception vectors
+ */
+ .text
+ . = EXC_OFF_SYS_RESET
+ .globl _start
+_start:
+ li r21, BOOTFLAG_COLD /* Normal Power-On */
+ 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:
+boot_warm:
+ mfmsr r5 /* save msr contents */
+
+ /* replace default MBAR base address from 0x80000000
+ to 0xf0000000 */
+
+#if defined(CONFIG_SYS_DEFAULT_MBAR) && !defined(CONFIG_SYS_RAMBOOT)
+ lis r3, CONFIG_SYS_MBAR@h
+ ori r3, r3, CONFIG_SYS_MBAR@l
+
+ /* MBAR is mirrored into the MBAR SPR */
+ mtspr MBAR,r3
+ mtspr SPRN_SPRG7W,r3
+ lis r4, CONFIG_SYS_DEFAULT_MBAR@h
+ stw r3, 0(r4)
+#endif /* CONFIG_SYS_DEFAULT_MBAR */
+
+ /* Initialise the MPC8220 processor core */
+ /*--------------------------------------------------------------*/
+
+ bl init_8220_core
+
+ /* initialize some things that are hard to access from C */
+ /*--------------------------------------------------------------*/
+
+ /* set up stack in on-chip SRAM */
+ lis r3, CONFIG_SYS_INIT_RAM_ADDR@h
+ ori r3, r3, CONFIG_SYS_INIT_RAM_ADDR@l
+ ori r1, r3, CONFIG_SYS_INIT_SP_OFFSET
+
+ 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 */
+
+ /* 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 (in Flash)*/
+
+ mr r3, r21
+ /* r3: BOOTFLAG */
+ bl board_init_f /* run 1st part of board init code (in Flash)*/
+
+/*
+ * 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. */
+ 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
+ EXC_XFER_TEMPLATE(Alignment, AlignmentException, MSR_KERNEL, COPY_EE)
+
+/* Program check exception */
+ . = 0x700
+ProgramCheck:
+ EXCEPTION_PROLOG(SRR0, SRR1)
+ addi r3,r1,STACK_FRAME_OVERHEAD
+ EXC_XFER_TEMPLATE(ProgramCheck, ProgramCheckException,
+ MSR_KERNEL, COPY_EE)
+
+ 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 MPC8220 processor core
+ * (conforms to PowerPC 603e spec)
+ * Note: expects original MSR contents to be in r5.
+ */
+
+ .globl init_8220_core
+init_8220_core:
+
+ /* 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 */
+
+ /* Initialize the Hardware Implementation-dependent Registers */
+ /* HID0 also contains cache control */
+ /*--------------------------------------------------------------*/
+
+ lis r3, CONFIG_SYS_HID0_INIT@h
+ ori r3, r3, CONFIG_SYS_HID0_INIT@l
+ SYNC
+ mtspr HID0, r3
+
+ lis r3, CONFIG_SYS_HID0_FINAL@h
+ ori r3, r3, CONFIG_SYS_HID0_FINAL@l
+ SYNC
+ mtspr HID0, r3
+
+ /* Enable Extra BATs */
+ mfspr r3, 1011 /* HID2 */
+ lis r4, 0x0004
+ ori r4, r4, 0x0000
+ or r4, r4, r3
+ mtspr 1011, r4
+ sync
+
+ /* clear all BAT's */
+ /*--------------------------------------------------------------*/
+
+ li r0, 0
+ 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 DBAT4U, r0
+ mtspr DBAT4L, r0
+ mtspr DBAT5U, r0
+ mtspr DBAT5L, r0
+ mtspr DBAT6U, r0
+ mtspr DBAT6L, r0
+ mtspr DBAT7U, r0
+ mtspr DBAT7L, 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
+ mtspr IBAT4U, r0
+ mtspr IBAT4L, r0
+ mtspr IBAT5U, r0
+ mtspr IBAT5L, r0
+ mtspr IBAT6U, r0
+ mtspr IBAT6L, r0
+ mtspr IBAT7U, r0
+ mtspr IBAT7L, 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/powerpc/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:
+ lis r4, 0
+ ori r4, r4, CONFIG_SYS_HID0_INIT /* set ICE & ICFI bit */
+ rlwinm r3, r4, 0, 21, 19 /* clear the ICFI bit */
+
+ /*
+ * The setting of the instruction cache enable (ICE) bit must be
+ * preceded by an isync instruction to prevent the cache from being
+ * enabled or disabled while an instruction access is in progress.
+ */
+ isync
+ mtspr HID0, r4 /* Enable Instr Cache & Inval cache */
+ mtspr HID0, r3 /* using 2 consec instructions */
+ isync
+ blr
+
+ .globl icache_disable
+icache_disable:
+ mfspr r3, HID0
+ rlwinm r3, r3, 0, 17, 15 /* clear the ICE bit */
+ mtspr HID0, r3
+ isync
+ blr
+
+ .globl icache_status
+icache_status:
+ mfspr r3, HID0
+ rlwinm r3, r3, HID0_ICE_BITPOS + 1, 31, 31
+ blr
+
+ .globl dcache_enable
+dcache_enable:
+ lis r4, 0
+ ori r4, r4, HID0_DCE|HID0_DCFI /* set DCE & DCFI bit */
+ rlwinm r3, r4, 0, 22, 20 /* clear the DCFI bit */
+
+ /* Enable address translation in MSR bit */
+ mfmsr r5
+ ori r5, r5, 0x
+
+
+ /*
+ * The setting of the instruction cache enable (ICE) bit must be
+ * preceded by an isync instruction to prevent the cache from being
+ * enabled or disabled while an instruction access is in progress.
+ */
+ isync
+ mtspr HID0, r4 /* Enable Data Cache & Inval cache*/
+ mtspr HID0, r3 /* using 2 consec instructions */
+ isync
+ blr
+
+ .globl dcache_disable
+dcache_disable:
+ mfspr r3, HID0
+ rlwinm r3, r3, 0, 18, 16 /* clear the DCE bit */
+ mtspr HID0, r3
+ isync
+ blr
+
+ .globl dcache_status
+dcache_status:
+ mfspr r3, HID0
+ rlwinm r3, r3, HID0_DCE_BITPOS + 1, 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 */
+
+ GET_GOT
+ mr r3, r5 /* Destination Address */
+ lis r4, CONFIG_SYS_MONITOR_BASE@h /* Source Address */
+ ori r4, r4, CONFIG_SYS_MONITOR_BASE@l
+ lwz r5, GOT(__init_end)
+ sub r5, r5, r4
+ li r6, CONFIG_SYS_CACHELINE_SIZE /* Cache Line Size */
+
+ /*
+ * Fix GOT pointer:
+ *
+ * New GOT-PTR = (old GOT-PTR - CONFIG_SYS_MONITOR_BASE) + Destination Address
+ *
+ * Offset:
+ */
+ sub r15, r10, r4
+
+ /* First our own GOT */
+ add r12, r12, 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)
+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
+
+/*
+ * Now flush the cache: note that we must start from a cache aligned
+ * address. Otherwise we might miss one cache line.
+ */
+4: 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_BITPOS+1,31,31
+ 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_ICE_BITPOS+1,31,31
+ 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, r12 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)
+ cmpwi r0,0
+ beq- 2f
+ add r0,r0,r11
+ stw r0,0(r3)
+2: bdnz 1b
+
+ /*
+ * Now adjust the fixups and the pointers to the fixups
+ * in case we need to move ourselves again.
+ */
+ 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:
+ mflr r4 /* save link register */
+ GET_GOT
+ 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 */
+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