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-rw-r--r--cpu/ppc4xx/start.S1425
1 files changed, 1425 insertions, 0 deletions
diff --git a/cpu/ppc4xx/start.S b/cpu/ppc4xx/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>
+ *
+ * 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 <config.h>
+#include <mpc8xx.h>
+#include <ppc4xx.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
+
+#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(_end)
+ GOT_ENTRY(.bss)
+ 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
+
+/*
+ * 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)
+ /*----------------------------------------------------------------------- */
+ /* 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(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 */
+
+
+ .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 */
+ 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
+ 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)
+
+ . = 0xc00
+/*
+ * r0 - SYSCALL number
+ * r3-... arguments
+ */
+SystemCall:
+ addis r11,r0,0 /* get functions table addr */
+ ori r11,r11,0 /* Note: this code is patched in trap_init */
+ addis r12,r0,0 /* get number of functions */
+ ori r12,r12,0
+
+ cmplw 0, r0, r12
+ bge 1f
+
+ rlwinm r0,r0,2,0,31 /* fn_addr = fn_tbl[r0] */
+ add r11,r11,r0
+ lwz r11,0(r11)
+
+ li r12,0xd00-4*3 /* save LR & SRRx */
+ mflr r0
+ stw r0,0(r12)
+ mfspr r0,SRR0
+ stw r0,4(r12)
+ mfspr r0,SRR1
+ stw r0,8(r12)
+
+ li r12,0xc00+_back-SystemCall
+ mtlr r12
+ mtspr SRR0,r11
+
+1: SYNC
+ rfi
+
+_back:
+
+ mfmsr r11 /* Disable interrupts */
+ li r12,0
+ ori r12,r12,MSR_EE
+ andc r11,r11,r12
+ SYNC /* Some chip revs need this... */
+ mtmsr r11
+ SYNC
+
+ li r12,0xd00-4*3 /* restore regs */
+ lwz r11,0(r12)
+ mtlr r11
+ lwz r11,4(r12)
+ mtspr SRR0,r11
+ lwz r11,8(r12)
+ mtspr SRR1,r11
+
+ SYNC
+ rfi
+
+ 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
+ lis r5, CFG_MONITOR_LEN@h /* Length in Bytes */
+ ori r5, r5, CFG_MONITOR_LEN@l
+ 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)
+ 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
+
+ /* Problems accessing "end" in C, so do it here */
+ .globl get_endaddr
+get_endaddr:
+ lwz r3,GOT(_end)
+ blr
+
+ /*
+ * 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)
+
+ rlwinm r9, r7, 0, 18, 31 /* _start & 0x3FFF */
+
+ 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