/* * Copyright (C) 1998 Dan Malek * Copyright (C) 1999 Magnus Damm * Copyright (C) 2000,2001,2002 Wolfgang Denk * * 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 */ /*------------------------------------------------------------------------------+ */ /* */ /* This source code has been made available to you by IBM on an AS-IS */ /* basis. Anyone receiving this source is licensed under IBM */ /* copyrights to use it in any way he or she deems fit, including */ /* copying it, modifying it, compiling it, and redistributing it either */ /* with or without modifications. No license under IBM patents or */ /* patent applications is to be implied by the copyright license. */ /* */ /* Any user of this software should understand that IBM cannot provide */ /* technical support for this software and will not be responsible for */ /* any consequences resulting from the use of this software. */ /* */ /* Any person who transfers this source code or any derivative work */ /* must include the IBM copyright notice, this paragraph, and the */ /* preceding two paragraphs in the transferred software. */ /* */ /* COPYRIGHT I B M CORPORATION 1995 */ /* LICENSED MATERIAL - PROGRAM PROPERTY OF I B M */ /*------------------------------------------------------------------------------- */ /* U-Boot - Startup Code for IBM 4xx PowerPC based Embedded Boards * * * The processor starts at 0xfffffffc and the code is executed * from flash/rom. * in memory, but as long we don't jump around before relocating. * board_init lies at a quite high address and when the cpu has * jumped there, everything is ok. * This works because the cpu gives the FLASH (CS0) the whole * address space at startup, and board_init lies as a echo of * the flash somewhere up there in the memorymap. * * board_init will change CS0 to be positioned at the correct * address and (s)dram will be positioned at address 0 */ #include #include #include #include #define _LINUX_CONFIG_H 1 /* avoid reading Linux autoconf.h file */ #include #include #include #include #ifndef CONFIG_IDENT_STRING #define CONFIG_IDENT_STRING "" #endif #ifdef CFG_INIT_DCACHE_CS # if (CFG_INIT_DCACHE_CS == 0) # define PBxAP pb0ap # define PBxCR pb0cr # endif # if (CFG_INIT_DCACHE_CS == 1) # define PBxAP pb1ap # define PBxCR pb1cr # endif # if (CFG_INIT_DCACHE_CS == 2) # define PBxAP pb2ap # define PBxCR pb2cr # endif # if (CFG_INIT_DCACHE_CS == 3) # define PBxAP pb3ap # define PBxCR pb3cr # endif # if (CFG_INIT_DCACHE_CS == 4) # define PBxAP pb4ap # define PBxCR pb4cr # endif # if (CFG_INIT_DCACHE_CS == 5) # define PBxAP pb5ap # define PBxCR pb5cr # endif # if (CFG_INIT_DCACHE_CS == 6) # define PBxAP pb6ap # define PBxCR pb6cr # endif # if (CFG_INIT_DCACHE_CS == 7) # define PBxAP pb7ap # define PBxCR pb7cr # endif #endif /* CFG_INIT_DCACHE_CS */ /* We don't want the MMU yet. */ #undef MSR_KERNEL #define MSR_KERNEL ( MSR_ME ) /* Machine Check */ .extern ext_bus_cntlr_init .extern sdram_init /* * 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 /* * 440 Startup -- on reset only the top 4k of the effective * address space is mapped in by an entry in the instruction * and data shadow TLB. The .bootpg section is located in the * top 4k & does only what's necessary to map in the the rest * of the boot rom. Once the boot rom is mapped in we can * proceed with normal startup. * * NOTE: CS0 only covers the top 2MB of the effective address * space after reset. */ #if defined(CONFIG_440) .section .bootpg,"ax" .globl _start_440 /**************************************************************************/ _start_440: /*----------------------------------------------------------------*/ /* Clear and set up some registers. */ /*----------------------------------------------------------------*/ iccci r0,r0 /* NOTE: operands not used for 440 */ dccci r0,r0 /* NOTE: operands not used for 440 */ sync li r0,0 mtspr srr0,r0 mtspr srr1,r0 mtspr csrr0,r0 mtspr csrr1,r0 /*----------------------------------------------------------------*/ /* Initialize debug */ /*----------------------------------------------------------------*/ mtspr dbcr0,r0 mtspr dbcr1,r0 mtspr dbcr2,r0 mtspr iac1,r0 mtspr iac2,r0 mtspr iac3,r0 mtspr dac1,r0 mtspr dac2,r0 mtspr dvc1,r0 mtspr dvc2,r0 mfspr r1,dbsr mtspr dbsr,r1 /* Clear all valid bits */ /*----------------------------------------------------------------*/ /* CCR0 init */ /*----------------------------------------------------------------*/ /* Disable store gathering & broadcast, guarantee inst/data * cache block touch, force load/store alignment * (see errata 1.12: 440_33) */ lis r1,0x0030 /* store gathering & broadcast disable */ ori r1,r1,0x6000 /* cache touch */ mtspr ccr0,r1 /*----------------------------------------------------------------*/ /* Setup interrupt vectors */ /*----------------------------------------------------------------*/ mtspr ivpr,r0 /* Vectors start at 0x0000_0000 */ li r1,0x0100 mtspr ivor0,r1 /* Critical input */ li r1,0x0200 mtspr ivor1,r1 /* Machine check */ li r1,0x0300 mtspr ivor2,r1 /* Data storage */ li r1,0x0400 mtspr ivor3,r1 /* Instruction storage */ li r1,0x0500 mtspr ivor4,r1 /* External interrupt */ li r1,0x0600 mtspr ivor5,r1 /* Alignment */ li r1,0x0700 mtspr ivor6,r1 /* Program check */ li r1,0x0800 mtspr ivor7,r1 /* Floating point unavailable */ li r1,0x0c00 mtspr ivor8,r1 /* System call */ li r1,0x1000 mtspr ivor10,r1 /* Decrementer (PIT for 440) */ li r1,0x1400 mtspr ivor13,r1 /* Data TLB error */ li r1,0x1300 mtspr ivor14,r1 /* Instr TLB error */ li r1,0x2000 mtspr ivor15,r1 /* Debug */ /*----------------------------------------------------------------*/ /* Configure cache regions */ /*----------------------------------------------------------------*/ mtspr inv0,r0 mtspr inv1,r0 mtspr inv2,r0 mtspr inv3,r0 mtspr dnv0,r0 mtspr dnv1,r0 mtspr dnv2,r0 mtspr dnv3,r0 mtspr itv0,r0 mtspr itv1,r0 mtspr itv2,r0 mtspr itv3,r0 mtspr dtv0,r0 mtspr dtv1,r0 mtspr dtv2,r0 mtspr dtv3,r0 /*----------------------------------------------------------------*/ /* Cache victim limits */ /*----------------------------------------------------------------*/ /* floors 0, ceiling max to use the entire cache -- nothing locked */ lis r1,0x0001 ori r1,r1,0xf800 mtspr ivlim,r1 mtspr dvlim,r1 /*----------------------------------------------------------------*/ /* Clear all TLB entries -- TID = 0, TS = 0 */ /*----------------------------------------------------------------*/ mtspr mmucr,r0 li r1,0x003f /* 64 TLB entries */ mtctr r1 0: tlbwe r0,r1,0x0000 /* Invalidate all entries (V=0)*/ subi r1,r1,0x0001 bdnz 0b /*----------------------------------------------------------------*/ /* TLB entry setup -- step thru tlbtab */ /*----------------------------------------------------------------*/ bl tlbtab /* Get tlbtab pointer */ mr r5,r0 li r1,0x003f /* 64 TLB entries max */ mtctr r1 li r4,0 /* TLB # */ addi r5,r5,-4 1: lwzu r0,4(r5) cmpwi r0,0 beq 2f /* 0 marks end */ lwzu r1,4(r5) lwzu r2,4(r5) tlbwe r0,r4,0 /* TLB Word 0 */ tlbwe r1,r4,1 /* TLB Word 1 */ tlbwe r2,r4,2 /* TLB Word 2 */ addi r4,r4,1 /* Next TLB */ bdnz 1b /*----------------------------------------------------------------*/ /* Continue from 'normal' start */ /*----------------------------------------------------------------*/ 2: bl 3f b _start 3: li r0,0 mtspr srr1,r0 /* Keep things disabled for now */ mflr r1 mtspr srr0,r1 rfi #endif /* CONFIG_440 */ /* * 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" /* * Maybe this should be moved somewhere else because the current * location (0x100) is where the CriticalInput Execption should be. */ . = EXC_OFF_SYS_RESET .globl _start _start: /*****************************************************************************/ #if defined(CONFIG_440) /*----------------------------------------------------------------*/ /* Clear and set up some registers. */ /*----------------------------------------------------------------*/ li r0,0x0000 lis r1,0xffff mtspr dec,r0 /* prevent dec exceptions */ mtspr tbl,r0 /* prevent fit & wdt exceptions */ mtspr tbu,r0 mtspr tsr,r1 /* clear all timer exception status */ mtspr tcr,r0 /* disable all */ mtspr esr,r0 /* clear exception syndrome register */ mtxer r0 /* clear integer exception register */ lis r1,0x0002 /* set CE bit (Critical Exceptions) */ ori r1,r1,0x1000 /* set ME bit (Machine Exceptions) */ mtmsr r1 /* change MSR */ /*----------------------------------------------------------------*/ /* Debug setup -- some (not very good) ice's need an event*/ /* to establish control :-( Define CFG_INIT_DBCR to the dbsr */ /* value you need in this case 0x8cff 0000 should do the trick */ /*----------------------------------------------------------------*/ #if defined(CFG_INIT_DBCR) lis r1,0xffff ori r1,r1,0xffff mtspr dbsr,r1 /* Clear all status bits */ lis r0,CFG_INIT_DBCR@h ori r0,r0,CFG_INIT_DBCR@l mtspr dbcr0,r0 isync #endif /*----------------------------------------------------------------*/ /* Setup the internal SRAM */ /*----------------------------------------------------------------*/ li r0,0 mtdcr isram0_sb1cr,r0 /* Disable bank 1 */ li r2,0x7fff ori r2,r2,0xffff mfdcr r1,isram0_dpc and r1,r1,r2 /* Disable parity check */ mtdcr isram0_dpc,r1 mfdcr r1,isram0_pmeg andis. r1,r1,r2 /* Disable pwr mgmt */ mtdcr isram0_pmeg,r1 lis r1,0x8000 /* BAS = 8000_0000 */ ori r1,r1,0x0380 /* 8k rw */ mtdcr isram0_sb0cr,r1 /*----------------------------------------------------------------*/ /* Setup the stack in internal SRAM */ /*----------------------------------------------------------------*/ lis r1,CFG_INIT_RAM_ADDR@h ori r1,r1,CFG_INIT_SP_OFFSET@l li r0,0 stwu r0,-4(r1) stwu r0,-4(r1) /* Terminate call chain */ stwu r1,-8(r1) /* Save back chain and move SP */ lis r0,RESET_VECTOR@h /* Address of reset vector */ ori r0,r0, RESET_VECTOR@l stwu r1,-8(r1) /* Save back chain and move SP */ stw r0,+12(r1) /* Save return addr (underflow vect) */ GET_GOT bl board_init_f #endif /* CONFIG_440 */ /*****************************************************************************/ #ifdef CONFIG_IOP480 /*----------------------------------------------------------------------- */ /* Set up some machine state registers. */ /*----------------------------------------------------------------------- */ addi r0,r0,0x0000 /* initialize r0 to zero */ mtspr esr,r0 /* clear Exception Syndrome Reg */ mttcr r0 /* timer control register */ mtexier r0 /* disable all interrupts */ addi r4,r0,0x1000 /* set ME bit (Machine Exceptions) */ oris r4,r4,0x2 /* set CE bit (Critical Exceptions) */ mtmsr r4 /* change MSR */ addis r4,r0,0xFFFF /* set r4 to 0xFFFFFFFF (status in the */ ori r4,r4,0xFFFF /* dbsr is cleared by setting bits to 1) */ mtdbsr r4 /* clear/reset the dbsr */ mtexisr r4 /* clear all pending interrupts */ addis r4,r0,0x8000 mtexier r4 /* enable critical exceptions */ addis r4,r0,0x0000 /* assume 403GCX - enable core clk */ ori r4,r4,0x4020 /* dbling (no harm done on GA and GC */ mtiocr r4 /* since bit not used) & DRC to latch */ /* data bus on rising edge of CAS */ /*----------------------------------------------------------------------- */ /* Clear XER. */ /*----------------------------------------------------------------------- */ mtxer r0 /*----------------------------------------------------------------------- */ /* Invalidate i-cache and d-cache TAG arrays. */ /*----------------------------------------------------------------------- */ addi r3,0,1024 /* 1/4 of I-cache size, half of D-cache */ addi r4,0,1024 /* 1/4 of I-cache */ ..cloop: iccci 0,r3 iccci r4,r3 dccci 0,r3 addic. r3,r3,-16 /* move back one cache line */ bne ..cloop /* loop back to do rest until r3 = 0 */ /* */ /* initialize IOP480 so it can read 1 MB code area for SRAM spaces */ /* this requires enabling MA[17..0], by default only MA[12..0] are enabled. */ /* */ /* first copy IOP480 register base address into r3 */ addis r3,0,0x5000 /* IOP480 register base address hi */ /* ori r3,r3,0x0000 / IOP480 register base address lo */ #ifdef CONFIG_ADCIOP /* use r4 as the working variable */ /* turn on CS3 (LOCCTL.7) */ lwz r4,0x84(r3) /* LOCTL is at offset 0x84 */ andi. r4,r4,0xff7f /* make bit 7 = 0 -- CS3 mode */ stw r4,0x84(r3) /* LOCTL is at offset 0x84 */ #endif #ifdef CONFIG_DASA_SIM /* use r4 as the working variable */ /* turn on MA17 (LOCCTL.7) */ lwz r4,0x84(r3) /* LOCTL is at offset 0x84 */ ori r4,r4,0x80 /* make bit 7 = 1 -- MA17 mode */ stw r4,0x84(r3) /* LOCTL is at offset 0x84 */ #endif /* turn on MA16..13 (LCS0BRD.12 = 0) */ lwz r4,0x100(r3) /* LCS0BRD is at offset 0x100 */ andi. r4,r4,0xefff /* make bit 12 = 0 */ stw r4,0x100(r3) /* LCS0BRD is at offset 0x100 */ /* make sure above stores all comlete before going on */ sync /* last thing, set local init status done bit (DEVINIT.31) */ lwz r4,0x80(r3) /* DEVINIT is at offset 0x80 */ oris r4,r4,0x8000 /* make bit 31 = 1 */ stw r4,0x80(r3) /* DEVINIT is at offset 0x80 */ /* clear all pending interrupts and disable all interrupts */ li r4,-1 /* set p1 to 0xffffffff */ stw r4,0x1b0(r3) /* clear all pending interrupts */ stw r4,0x1b8(r3) /* clear all pending interrupts */ li r4,0 /* set r4 to 0 */ stw r4,0x1b4(r3) /* disable all interrupts */ stw r4,0x1bc(r3) /* disable all interrupts */ /* make sure above stores all comlete before going on */ sync /*----------------------------------------------------------------------- */ /* Enable two 128MB cachable regions. */ /*----------------------------------------------------------------------- */ addis r1,r0,0x8000 addi r1,r1,0x0001 mticcr r1 /* instruction cache */ addis r1,r0,0x0000 addi r1,r1,0x0000 mtdccr r1 /* data cache */ addis r1,r0,CFG_INIT_RAM_ADDR@h ori r1,r1,CFG_INIT_SP_OFFSET /* set up the stack to SDRAM */ 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 */ GET_GOT /* initialize GOT access */ bl board_init_f /* run first part of init code (from Flash) */ #endif /* CONFIG_IOP480 */ /*****************************************************************************/ #if defined(CONFIG_405GP) || defined(CONFIG_405CR) || defined(CONFIG_405) || defined(CONFIG_405EP) /*----------------------------------------------------------------------- */ /* Clear and set up some registers. */ /*----------------------------------------------------------------------- */ addi r4,r0,0x0000 mtspr sgr,r4 mtspr dcwr,r4 mtesr r4 /* clear Exception Syndrome Reg */ mttcr r4 /* clear Timer Control Reg */ mtxer r4 /* clear Fixed-Point Exception Reg */ mtevpr r4 /* clear Exception Vector Prefix Reg */ addi r4,r0,0x1000 /* set ME bit (Machine Exceptions) */ oris r4,r4,0x0002 /* set CE bit (Critical Exceptions) */ mtmsr r4 /* change MSR */ addi r4,r0,(0xFFFF-0x10000) /* set r4 to 0xFFFFFFFF (status in the */ /* dbsr is cleared by setting bits to 1) */ mtdbsr r4 /* clear/reset the dbsr */ /*----------------------------------------------------------------------- */ /* Invalidate I and D caches. Enable I cache for defined memory regions */ /* to speed things up. Leave the D cache disabled for now. It will be */ /* enabled/left disabled later based on user selected menu options. */ /* Be aware that the I cache may be disabled later based on the menu */ /* options as well. See miscLib/main.c. */ /*----------------------------------------------------------------------- */ bl invalidate_icache bl invalidate_dcache /*----------------------------------------------------------------------- */ /* Enable two 128MB cachable regions. */ /*----------------------------------------------------------------------- */ addis r4,r0,0x8000 addi r4,r4,0x0001 mticcr r4 /* instruction cache */ isync addis r4,r0,0x0000 addi r4,r4,0x0000 mtdccr r4 /* data cache */ #if !(defined(CFG_EBC_PB0AP) && defined(CFG_EBC_PB0CR)) /*----------------------------------------------------------------------- */ /* Tune the speed and size for flash CS0 */ /*----------------------------------------------------------------------- */ bl ext_bus_cntlr_init #endif #if defined(CONFIG_405EP) /*----------------------------------------------------------------------- */ /* DMA Status, clear to come up clean */ /*----------------------------------------------------------------------- */ addis r3,r0, 0xFFFF /* Clear all existing DMA status */ ori r3,r3, 0xFFFF mtdcr dmasr, r3 bl ppc405ep_init /* do ppc405ep specific init */ #endif /* CONFIG_405EP */ #if defined(CFG_OCM_DATA_ADDR) && defined(CFG_OCM_DATA_SIZE) /******************************************************************** * Setup OCM - On Chip Memory *******************************************************************/ /* Setup OCM */ lis r0, 0x7FFF ori r0, r0, 0xFFFF mfdcr r3, ocmiscntl /* get instr-side IRAM config */ mfdcr r4, ocmdscntl /* get data-side IRAM config */ and r3, r3, r0 /* disable data-side IRAM */ and r4, r4, r0 /* disable data-side IRAM */ mtdcr ocmiscntl, r3 /* set instr-side IRAM config */ mtdcr ocmdscntl, r4 /* set data-side IRAM config */ isync addis r3, 0, CFG_OCM_DATA_ADDR@h /* OCM location */ mtdcr ocmdsarc, r3 addis r4, 0, 0xC000 /* OCM data area enabled */ mtdcr ocmdscntl, r4 isync #endif /*----------------------------------------------------------------------- */ /* Setup temporary stack in DCACHE or OCM if needed for SDRAM SPD. */ /*----------------------------------------------------------------------- */ #ifdef CFG_INIT_DCACHE_CS /*----------------------------------------------------------------------- */ /* Memory Bank x (nothingness) initialization 1GB+64MEG */ /* used as temporary stack pointer for stage0 */ /*----------------------------------------------------------------------- */ li r4,PBxAP mtdcr ebccfga,r4 lis r4,0x0380 ori r4,r4,0x0480 mtdcr ebccfgd,r4 addi r4,0,PBxCR mtdcr ebccfga,r4 lis r4,0x400D ori r4,r4,0xa000 mtdcr ebccfgd,r4 /* turn on data chache for this region */ lis r4,0x0080 mtdccr r4 /* set stack pointer and clear stack to known value */ lis r1,CFG_INIT_RAM_ADDR@h ori r1,r1,CFG_INIT_SP_OFFSET@l li r4,2048 /* we store 2048 words to stack */ mtctr r4 lis r2,CFG_INIT_RAM_ADDR@h /* we also clear data area */ ori r2,r2,CFG_INIT_RAM_END@l /* so cant copy value from r1 */ lis r4,0xdead /* we store 0xdeaddead in the stack */ ori r4,r4,0xdead ..stackloop: stwu r4,-4(r2) bdnz ..stackloop 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 */ /* * Set up a dummy frame to store reset vector as return address. * this causes stack underflow to reset board. */ stwu r1, -8(r1) /* Save back chain and move SP */ addis r0, 0, RESET_VECTOR@h /* Address of reset vector */ ori r0, r0, RESET_VECTOR@l stwu r1, -8(r1) /* Save back chain and move SP */ stw r0, +12(r1) /* Save return addr (underflow vect) */ #elif defined(CFG_TEMP_STACK_OCM) && \ (defined(CFG_OCM_DATA_ADDR) && defined(CFG_OCM_DATA_SIZE)) /* * Stack in OCM. */ /* Set up Stack at top of OCM */ lis r1, (CFG_INIT_RAM_ADDR + CFG_INIT_SP_OFFSET)@h ori r1, r1, (CFG_INIT_RAM_ADDR + CFG_INIT_SP_OFFSET)@l /* Set up a zeroized stack frame so that backtrace works right */ li r0, 0 stwu r0, -4(r1) stwu r0, -4(r1) /* * Set up a dummy frame to store reset vector as return address. * this causes stack underflow to reset board. */ stwu r1, -8(r1) /* Save back chain and move SP */ lis r0, RESET_VECTOR@h /* Address of reset vector */ ori r0, r0, RESET_VECTOR@l stwu r1, -8(r1) /* Save back chain and move SP */ stw r0, +12(r1) /* Save return addr (underflow vect) */ #endif /* CFG_INIT_DCACHE_CS */ /*----------------------------------------------------------------------- */ /* Initialize SDRAM Controller */ /*----------------------------------------------------------------------- */ bl sdram_init /* * Setup temporary stack pointer only for boards * that do not use SDRAM SPD I2C stuff since it * is already initialized to use DCACHE or OCM * stacks. */ #if !(defined(CFG_INIT_DCACHE_CS) || defined(CFG_TEMP_STACK_OCM)) lis r1, CFG_INIT_RAM_ADDR@h ori r1,r1,CFG_INIT_SP_OFFSET /* set up the stack in SDRAM */ 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 */ /* * Set up a dummy frame to store reset vector as return address. * this causes stack underflow to reset board. */ stwu r1, -8(r1) /* Save back chain and move SP */ lis r0, RESET_VECTOR@h /* Address of reset vector */ ori r0, r0, RESET_VECTOR@l stwu r1, -8(r1) /* Save back chain and move SP */ stw r0, +12(r1) /* Save return addr (underflow vect) */ #endif /* !(CFG_INIT_DCACHE_CS || !CFG_TEM_STACK_OCM) */ GET_GOT /* initialize GOT access */ bl cpu_init_f /* run low-level CPU init code (from Flash) */ /* NEVER RETURNS! */ bl board_init_f /* run first part of init code (from Flash) */ #endif /* CONFIG_405GP || CONFIG_405CR || CONFIG_405 || CONFIG_405EP */ /*----------------------------------------------------------------------- */ /*****************************************************************************/ .globl _start_of_vectors _start_of_vectors: #if 0 /*TODO Fixup _start above so we can do this*/ /* Critical input. */ CRIT_EXCEPTION(0x100, CritcalInput, CritcalInputException) #endif /* Machine check */ CRIT_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 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 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 /* No FPU on MPC8xx. This exception is not supposed to happen. */ 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, PIT, PITException) 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, UnknownException) STD_EXCEPTION(0x1e00, PeripheralBreakpoint, UnknownException) STD_EXCEPTION(0x1f00, DevPortBreakpoint, UnknownException) CRIT_EXCEPTION(0x2000, DebugBreakpoint, DebugException ) .globl _end_of_vectors _end_of_vectors: . = 0x2100 /* * 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) #if 0 andi. r23,r23,MSR_PR mfspr r23,SPRG3 /* if from user, fix up tss.regs */ beq 2f addi r24,r1,STACK_FRAME_OVERHEAD stw r24,PT_REGS(r23) 2: addi r2,r23,-TSS /* set r2 to current */ tovirt(r2,r2,r23) #endif 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 */ #if 0 addi r24,r2,TASK_STRUCT_SIZE /* check for kernel stack overflow */ cmplw 0,r1,r2 cmplw 1,r1,r24 crand 1,1,4 bgt stack_ovf /* if r2 < r1 < r2+TASK_STRUCT_SIZE */ #endif 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 crit_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 990,r2 /* SRR2 */ mtspr 991,r0 /* SRR3 */ lwz r0,GPR0(r1) lwz r2,GPR2(r1) lwz r1,GPR1(r1) SYNC rfci /* Cache functions. */ invalidate_icache: iccci r0,r0 /* for 405, iccci invalidates the */ blr /* entire I cache */ invalidate_dcache: addi r6,0,0x0000 /* clear GPR 6 */ /* Do loop for # of dcache congruence classes. */ addi r7,r0, (CFG_DCACHE_SIZE / CFG_CACHELINE_SIZE / 2) /* NOTE: dccci invalidates both */ mtctr r7 /* ways in the D cache */ ..dcloop: dccci 0,r6 /* invalidate line */ addi r6,r6, CFG_CACHELINE_SIZE /* bump to next line */ bdnz ..dcloop blr flush_dcache: addis r9,r0,0x0002 /* set mask for EE and CE msr bits */ ori r9,r9,0x8000 mfmsr r12 /* save msr */ andc r9,r12,r9 mtmsr r9 /* disable EE and CE */ addi r10,r0,0x0001 /* enable data cache for unused memory */ mfdccr r9 /* region 0xF8000000-0xFFFFFFFF via */ or r10,r10,r9 /* bit 31 in dccr */ mtdccr r10 /* do loop for # of congruence classes. */ addi r10,r0,(CFG_DCACHE_SIZE / CFG_CACHELINE_SIZE / 2) addi r11,r0,(CFG_DCACHE_SIZE / 2) /* D cache set size - 2 way sets */ mtctr r10 addi r10,r0,(0xE000-0x10000) /* start at 0xFFFFE000 */ add r11,r10,r11 /* add to get to other side of cache line */ ..flush_dcache_loop: lwz r3,0(r10) /* least recently used side */ lwz r3,0(r11) /* the other side */ dccci r0,r11 /* invalidate both sides */ addi r10,r10,CFG_CACHELINE_SIZE /* bump to next line */ addi r11,r11,CFG_CACHELINE_SIZE /* bump to next line */ bdnz ..flush_dcache_loop sync /* allow memory access to complete */ mtdccr r9 /* restore dccr */ mtmsr r12 /* restore msr */ blr .globl icache_enable icache_enable: mflr r8 bl invalidate_icache mtlr r8 isync addis r3,r0, 0x8000 /* set bit 0 */ mticcr r3 blr .globl icache_disable icache_disable: addis r3,r0, 0x0000 /* clear bit 0 */ mticcr r3 isync blr .globl icache_status icache_status: mficcr r3 srwi r3, r3, 31 /* >>31 => select bit 0 */ blr .globl dcache_enable dcache_enable: mflr r8 bl invalidate_dcache mtlr r8 isync addis r3,r0, 0x8000 /* set bit 0 */ mtdccr r3 blr .globl dcache_disable dcache_disable: mflr r8 bl flush_dcache mtlr r8 addis r3,r0, 0x0000 /* clear bit 0 */ mtdccr r3 blr .globl dcache_status dcache_status: mfdccr r3 srwi r3, r3, 31 /* >>31 => select bit 0 */ blr .globl get_pvr get_pvr: mfspr r3, PVR blr #if !defined(CONFIG_440) .globl wr_pit wr_pit: mtspr pit, r3 blr #endif .globl wr_tcr wr_tcr: mtspr tcr, r3 blr /*------------------------------------------------------------------------------- */ /* Function: in8 */ /* Description: Input 8 bits */ /*------------------------------------------------------------------------------- */ .globl in8 in8: lbz r3,0x0000(r3) blr /*------------------------------------------------------------------------------- */ /* Function: out8 */ /* Description: Output 8 bits */ /*------------------------------------------------------------------------------- */ .globl out8 out8: stb r4,0x0000(r3) blr /*------------------------------------------------------------------------------- */ /* Function: out16 */ /* Description: Output 16 bits */ /*------------------------------------------------------------------------------- */ .globl out16 out16: sth r4,0x0000(r3) blr /*------------------------------------------------------------------------------- */ /* Function: out16r */ /* Description: Byte reverse and output 16 bits */ /*------------------------------------------------------------------------------- */ .globl out16r out16r: sthbrx r4,r0,r3 blr /*------------------------------------------------------------------------------- */ /* Function: out32 */ /* Description: Output 32 bits */ /*------------------------------------------------------------------------------- */ .globl out32 out32: stw r4,0x0000(r3) blr /*------------------------------------------------------------------------------- */ /* Function: out32r */ /* Description: Byte reverse and output 32 bits */ /*------------------------------------------------------------------------------- */ .globl out32r out32r: stwbrx r4,r0,r3 blr /*------------------------------------------------------------------------------- */ /* Function: in16 */ /* Description: Input 16 bits */ /*------------------------------------------------------------------------------- */ .globl in16 in16: lhz r3,0x0000(r3) blr /*------------------------------------------------------------------------------- */ /* Function: in16r */ /* Description: Input 16 bits and byte reverse */ /*------------------------------------------------------------------------------- */ .globl in16r in16r: lhbrx r3,r0,r3 blr /*------------------------------------------------------------------------------- */ /* Function: in32 */ /* Description: Input 32 bits */ /*------------------------------------------------------------------------------- */ .globl in32 in32: lwz 3,0x0000(3) blr /*------------------------------------------------------------------------------- */ /* Function: in32r */ /* Description: Input 32 bits and byte reverse */ /*------------------------------------------------------------------------------- */ .globl in32r in32r: lwbrx r3,r0,r3 blr /*------------------------------------------------------------------------------- */ /* Function: ppcDcbf */ /* Description: Data Cache block flush */ /* Input: r3 = effective address */ /* Output: none. */ /*------------------------------------------------------------------------------- */ .globl ppcDcbf ppcDcbf: dcbf r0,r3 blr /*------------------------------------------------------------------------------- */ /* Function: ppcDcbi */ /* Description: Data Cache block Invalidate */ /* Input: r3 = effective address */ /* Output: none. */ /*------------------------------------------------------------------------------- */ .globl ppcDcbi ppcDcbi: dcbi r0,r3 blr /*------------------------------------------------------------------------------- */ /* Function: ppcSync */ /* Description: Processor Synchronize */ /* Input: none. */ /* Output: none. */ /*------------------------------------------------------------------------------- */ .globl ppcSync ppcSync: sync 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 Init 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 /* 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 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 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 */ 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 /* NEVER RETURNS! */ 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 /* Init 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) blr /**************************************************************************/ /* PPC405EP specific stuff */ /**************************************************************************/ #ifdef CONFIG_405EP ppc405ep_init: /* !----------------------------------------------------------------------- ! Check FPGA for PCI internal/external arbitration ! If board is set to internal arbitration, update cpc0_pci !----------------------------------------------------------------------- */ addi r3,0,CPC0_PCI_HOST_CFG_EN #ifdef CONFIG_BUBINGA405EP addis r5,r0,FPGA_REG1@h /* set offset for FPGA_REG1 */ ori r5,r5,FPGA_REG1@l lbz r5,0x0(r5) /* read to get PCI arb selection */ andi. r6,r5,FPGA_REG1_PCI_INT_ARB /* using internal arbiter ?*/ beq ..pci_cfg_set /* if not set, then bypass reg write*/ #endif ori r3,r3,CPC0_PCI_ARBIT_EN ..pci_cfg_set: mtdcr CPC0_PCI, r3 /* Enable internal arbiter*/ /* !----------------------------------------------------------------------- ! Check to see if chip is in bypass mode. ! If so, write stored CPC0_PLLMR0 and CPC0_PLLMR1 values and perform a ! CPU reset Otherwise, skip this step and keep going. ! Note: Running BIOS in bypass mode is not supported since PLB speed ! will not be fast enough for the SDRAM (min 66MHz) !----------------------------------------------------------------------- */ mfdcr r5, CPC0_PLLMR1 rlwinm r4,r5,1,0x1 /* get system clock source (SSCS) */ cmpi cr0,0,r4,0x1 beq pll_done /* if SSCS =b'1' then PLL has */ /* already been set */ /* and CPU has been reset */ /* so skip to next section */ #ifdef CONFIG_BUBINGA405EP /* !----------------------------------------------------------------------- ! Read NVRAM to get value to write in PLLMR. ! If value has not been correctly saved, write default value ! Default config values (assuming on-board 33MHz SYS_CLK) are above. ! See CPU_DEFAULT_200 and CPU_DEFAULT_266 above. ! ! WARNING: This code assumes the first three words in the nvram_t ! structure in openbios.h. Changing the beginning of ! the structure will break this code. ! !----------------------------------------------------------------------- */ addis r3,0,NVRAM_BASE@h addi r3,r3,NVRAM_BASE@l lwz r4, 0(r3) addis r5,0,NVRVFY1@h addi r5,r5,NVRVFY1@l cmp cr0,0,r4,r5 /* Compare 1st NVRAM Magic number*/ bne ..no_pllset addi r3,r3,4 lwz r4, 0(r3) addis r5,0,NVRVFY2@h addi r5,r5,NVRVFY2@l cmp cr0,0,r4,r5 /* Compare 2 NVRAM Magic number */ bne ..no_pllset addi r3,r3,8 /* Skip over conf_size */ lwz r4, 4(r3) /* Load PLLMR1 value from NVRAM */ lwz r3, 0(r3) /* Load PLLMR0 value from NVRAM */ rlwinm r5,r4,1,0x1 /* get system clock source (SSCS) */ cmpi cr0,0,r5,1 /* See if PLL is locked */ beq pll_write ..no_pllset: #endif /* CONFIG_BUBINGA405EP */ addis r3,0,PLLMR0_DEFAULT@h /* PLLMR0 default value */ ori r3,r3,PLLMR0_DEFAULT@l /* */ addis r4,0,PLLMR1_DEFAULT@h /* PLLMR1 default value */ ori r4,r4,PLLMR1_DEFAULT@l /* */ b pll_write /* Write the CPC0_PLLMR with new value */ pll_done: /* !----------------------------------------------------------------------- ! Clear Soft Reset Register ! This is needed to enable PCI if not booting from serial EPROM !----------------------------------------------------------------------- */ addi r3, 0, 0x0 mtdcr CPC0_SRR, r3 addis r3,0,0x0010 mtctr r3 pci_wait: bdnz pci_wait blr /* return to main code */ /* !----------------------------------------------------------------------------- ! Function: pll_write ! Description: Updates the value of the CPC0_PLLMR according to CMOS27E documentation ! That is: ! 1. Pll is first disabled (de-activated by putting in bypass mode) ! 2. PLL is reset ! 3. Clock dividers are set while PLL is held in reset and bypassed ! 4. PLL Reset is cleared ! 5. Wait 100us for PLL to lock ! 6. A core reset is performed ! Input: r3 = Value to write to CPC0_PLLMR0 ! Input: r4 = Value to write to CPC0_PLLMR1 ! Output r3 = none !----------------------------------------------------------------------------- */ pll_write: mfdcr r5, CPC0_UCR andis. r5,r5,0xFFFF ori r5,r5,0x0101 /* Stop the UART clocks */ mtdcr CPC0_UCR,r5 /* Before changing PLL */ mfdcr r5, CPC0_PLLMR1 rlwinm r5,r5,0,0x7FFFFFFF /* Disable PLL */ mtdcr CPC0_PLLMR1,r5 oris r5,r5,0x4000 /* Set PLL Reset */ mtdcr CPC0_PLLMR1,r5 mtdcr CPC0_PLLMR0,r3 /* Set clock dividers */ rlwinm r5,r4,0,0x3FFFFFFF /* Reset & Bypass new PLL dividers */ oris r5,r5,0x4000 /* Set PLL Reset */ mtdcr CPC0_PLLMR1,r5 /* Set clock dividers */ rlwinm r5,r5,0,0xBFFFFFFF /* Clear PLL Reset */ mtdcr CPC0_PLLMR1,r5 /* ! Wait min of 100us for PLL to lock. ! See CMOS 27E databook for more info. ! At 200MHz, that means waiting 20,000 instructions */ addi r3,0,20000 /* 2000 = 0x4e20 */ mtctr r3 pll_wait: bdnz pll_wait oris r5,r5,0x8000 /* Enable PLL */ mtdcr CPC0_PLLMR1,r5 /* Engage */ /* * Reset CPU to guarantee timings are OK * Not sure if this is needed... */ addis r3,0,0x1000 mtspr dbcr0,r3 /* This will cause a CPU core reset, and */ /* execution will continue from the poweron */ /* vector of 0xfffffffc */ #endif /* CONFIG_405EP */