[J-u-boot.git] / cpu / mpc8220 / start.S

/*
 *  Copyright (C) 1998	Dan Malek <[email protected]>
 *  Copyright (C) 1999	Magnus Damm <kieraypc01.p.y.kie.era.ericsson.se>
 *  Copyright (C) 2000 - 2003 Wolfgang Denk <[email protected]>
 *
 * 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 <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 r14 to access the GOT
 */
	START_GOT
	GOT_ENTRY(_GOT2_TABLE_)
	GOT_ENTRY(_FIXUP_TABLE_)

	GOT_ENTRY(_start)
	GOT_ENTRY(_start_of_vectors)
	GOT_ENTRY(_end_of_vectors)
	GOT_ENTRY(transfer_to_handler)

	GOT_ENTRY(__init_end)
	GOT_ENTRY(_end)
	GOT_ENTRY(__bss_start)
	END_GOT

/*
 * Version string
 */
	.data
	.globl	version_string
version_string:
	.ascii U_BOOT_VERSION
	.ascii " (", __DATE__, " - ", __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
	li	r20,MSR_KERNEL
	rlwimi	r20,r23,0,16,16	    /* copy EE bit from saved MSR */
	rlwimi	r20,r23,0,25,25	    /* copy IP bit from saved MSR */
	lwz	r6,GOT(transfer_to_handler)
	mtlr	r6
	blrl
.L_Alignment:
	.long	AlignmentException - _start + EXC_OFF_SYS_RESET
	.long	int_return - _start + EXC_OFF_SYS_RESET

/* Program check exception */
	. = 0x700
ProgramCheck:
	EXCEPTION_PROLOG(SRR0, SRR1)
	addi	r3,r1,STACK_FRAME_OVERHEAD
	li	r20,MSR_KERNEL
	rlwimi	r20,r23,0,16,16	    /* copy EE bit from saved MSR */
	rlwimi	r20,r23,0,25,25	    /* copy IP bit from saved MSR */
	lwz	r6,GOT(transfer_to_handler)
	mtlr	r6
	blrl
.L_ProgramCheck:
	.long	ProgramCheckException - _start + EXC_OFF_SYS_RESET
	.long	int_return - _start + EXC_OFF_SYS_RESET

	STD_EXCEPTION(0x800, FPUnavailable, UnknownException)

	/* I guess we could implement decrementer, and may have
	 * to someday for timekeeping.
	 */
	STD_EXCEPTION(0x900, Decrementer, timer_interrupt)

	STD_EXCEPTION(0xa00, Trap_0a, UnknownException)
	STD_EXCEPTION(0xb00, Trap_0b, UnknownException)
	STD_EXCEPTION(0xc00, SystemCall, UnknownException)
	STD_EXCEPTION(0xd00, SingleStep, UnknownException)

	STD_EXCEPTION(0xe00, Trap_0e, UnknownException)
	STD_EXCEPTION(0xf00, Trap_0f, UnknownException)

	STD_EXCEPTION(0x1000, InstructionTLBMiss, UnknownException)
	STD_EXCEPTION(0x1100, DataLoadTLBMiss, UnknownException)
	STD_EXCEPTION(0x1200, DataStoreTLBMiss, UnknownException)
#ifdef DEBUG
	. = 0x1300
	/*
	 * This exception occurs when the program counter matches the
	 * Instruction Address Breakpoint Register (IABR).
	 *
	 * I want the cpu to halt if this occurs so I can hunt around
	 * with the debugger and look at things.
	 *
	 * When DEBUG is defined, both machine check enable (in the MSR)
	 * and checkstop reset enable (in the reset mode register) are
	 * turned off and so a checkstop condition will result in the cpu
	 * halting.
	 *
	 * I force the cpu into a checkstop condition by putting an illegal
	 * instruction here (at least this is the theory).
	 *
	 * well - that didnt work, so just do an infinite loop!
	 */
1:	b	1b
#else
	STD_EXCEPTION(0x1300, InstructionBreakpoint, DebugException)
#endif
	STD_EXCEPTION(0x1400, SMI, UnknownException)

	STD_EXCEPTION(0x1500, Trap_15, UnknownException)
	STD_EXCEPTION(0x1600, Trap_16, UnknownException)
	STD_EXCEPTION(0x1700, Trap_17, UnknownException)
	STD_EXCEPTION(0x1800, Trap_18, UnknownException)
	STD_EXCEPTION(0x1900, Trap_19, UnknownException)
	STD_EXCEPTION(0x1a00, Trap_1a, UnknownException)
	STD_EXCEPTION(0x1b00, Trap_1b, UnknownException)
	STD_EXCEPTION(0x1c00, Trap_1c, UnknownException)
	STD_EXCEPTION(0x1d00, Trap_1d, UnknownException)
	STD_EXCEPTION(0x1e00, Trap_1e, UnknownException)
	STD_EXCEPTION(0x1f00, Trap_1f, UnknownException)
	STD_EXCEPTION(0x2000, Trap_20, UnknownException)
	STD_EXCEPTION(0x2100, Trap_21, UnknownException)
	STD_EXCEPTION(0x2200, Trap_22, UnknownException)
	STD_EXCEPTION(0x2300, Trap_23, UnknownException)
	STD_EXCEPTION(0x2400, Trap_24, UnknownException)
	STD_EXCEPTION(0x2500, Trap_25, UnknownException)
	STD_EXCEPTION(0x2600, Trap_26, UnknownException)
	STD_EXCEPTION(0x2700, Trap_27, UnknownException)
	STD_EXCEPTION(0x2800, Trap_28, UnknownException)
	STD_EXCEPTION(0x2900, Trap_29, UnknownException)
	STD_EXCEPTION(0x2a00, Trap_2a, UnknownException)
	STD_EXCEPTION(0x2b00, Trap_2b, UnknownException)
	STD_EXCEPTION(0x2c00, Trap_2c, UnknownException)
	STD_EXCEPTION(0x2d00, Trap_2d, UnknownException)
	STD_EXCEPTION(0x2e00, Trap_2e, UnknownException)
	STD_EXCEPTION(0x2f00, Trap_2f, UnknownException)


	.globl	_end_of_vectors
_end_of_vectors:

	. = 0x3000

/*
 * This code finishes saving the registers to the exception frame
 * and jumps to the appropriate handler for the exception.
 * Register r21 is pointer into trap frame, r1 has new stack pointer.
 */
	.globl	transfer_to_handler
transfer_to_handler:
	stw	r22,_NIP(r21)
	lis	r22,MSR_POW@h
	andc	r23,r23,r22
	stw	r23,_MSR(r21)
	SAVE_GPR(7, r21)
	SAVE_4GPRS(8, r21)
	SAVE_8GPRS(12, r21)
	SAVE_8GPRS(24, r21)
	mflr	r23
	andi.	r24,r23,0x3f00	    /* get vector offset */
	stw	r24,TRAP(r21)
	li	r22,0
	stw	r22,RESULT(r21)
	lwz	r24,0(r23)		/* virtual address of handler */
	lwz	r23,4(r23)		/* where to go when done */
	mtspr	SRR0,r24
	mtspr	SRR1,r20
	mtlr	r23
	SYNC
	rfi			    /* jump to handler, enable MMU */

int_return:
	mfmsr	r28		    /* Disable interrupts */
	li	r4,0
	ori	r4,r4,MSR_EE
	andc	r28,r28,r4
	SYNC			    /* Some chip revs need this... */
	mtmsr	r28
	SYNC
	lwz	r2,_CTR(r1)
	lwz	r0,_LINK(r1)
	mtctr	r2
	mtlr	r0
	lwz	r2,_XER(r1)
	lwz	r0,_CCR(r1)
	mtspr	XER,r2
	mtcrf	0xFF,r0
	REST_10GPRS(3, r1)
	REST_10GPRS(13, r1)
	REST_8GPRS(23, r1)
	REST_GPR(31, r1)
	lwz	r2,_NIP(r1)	    /* Restore environment */
	lwz	r0,_MSR(r1)
	mtspr	SRR0,r2
	mtspr	SRR1,r0
	lwz	r0,GPR0(r1)
	lwz	r2,GPR2(r1)
	lwz	r1,GPR1(r1)
	SYNC
	rfi

/*
 * This code initialises the 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/ppc/kernel/head.S	*/
	/*								*/
	/*--------------------------------------------------------------*/

	li	r3, 32
	mtctr	r3
	li	r3, 0
1:	tlbie	r3
	addi	r3, r3, 0x1000
	bdnz	1b
	SYNC

	/* Done!							*/
	/*--------------------------------------------------------------*/

	blr

/* Cache functions.
 *
 * Note: requires that all cache bits in
 * HID0 are in the low half word.
 */
	.globl	icache_enable
icache_enable:
	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 */

	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	r14, r14, r15
	/* then the one used by the C code */
	add	r30, r30, r15

	/*
	 * Now relocate code
	 */

	cmplw	cr1,r3,r4
	addi	r0,r5,3
	srwi.	r0,r0,2
	beq	cr1,4f	    /* In place copy is not necessary	*/
	beq	7f	    /* Protect against 0 count		*/
	mtctr	r0
	bge	cr1,2f

	la	r8,-4(r4)
	la	r7,-4(r3)
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, r14 point to got2+0x8000
	 *
	 * Adjust got2 pointers, no need to check for 0, this code
	 * already puts a few entries in the table.
	 */
	li	r0,__got2_entries@sectoff@l
	la	r3,GOT(_GOT2_TABLE_)
	lwz	r11,GOT(_GOT2_TABLE_)
	mtctr	r0
	sub	r11,r3,r11
	addi	r3,r3,-4
1:	lwzu	r0,4(r3)
	add	r0,r0,r11
	stw	r0,0(r3)
	bdnz	1b

	/*
	 * Now adjust the fixups and the pointers to the fixups
	 * in case we need to move ourselves again.
	 */
2:	li	r0,__fixup_entries@sectoff@l
	lwz	r3,GOT(_FIXUP_TABLE_)
	cmpwi	r0,0
	mtctr	r0
	addi	r3,r3,-4
	beq	4f
3:	lwzu	r4,4(r3)
	lwzux	r0,r4,r11
	add	r0,r0,r11
	stw	r10,0(r3)
	stw	r0,0(r4)
	bdnz	3b
4:
clear_bss:
	/*
	 * Now clear BSS segment
	 */
	lwz	r3,GOT(__bss_start)
	lwz	r4,GOT(_end)

	cmplw	0, r3, r4
	beq	6f

	li	r0, 0
5:
	stw	r0, 0(r3)
	addi	r3, r3, 4
	cmplw	0, r3, r4
	bne	5b
6:

	mr	r3, r9	    /* Global Data pointer	*/
	mr	r4, r10	    /* Destination Address	*/
	bl	board_init_r

	/*
	 * Copy exception vector code to low memory
	 *
	 * r3: dest_addr
	 * r7: source address, r8: end address, r9: target address
	 */
	.globl	trap_init
trap_init:
	lwz	r7, GOT(_start)
	lwz	r8, GOT(_end_of_vectors)

	li	r9, 0x100   /* reset vector always at 0x100	*/

	cmplw	0, r7, r8
	bgelr		    /* return if r7>=r8 - just in case	*/

	mflr	r4	    /* save link register		*/
1:
	lwz	r0, 0(r7)
	stw	r0, 0(r9)
	addi	r7, r7, 4
	addi	r9, r9, 4
	cmplw	0, r7, r8
	bne	1b

	/*
	 * relocate `hdlr' and `int_return' entries
	 */
	li	r7, .L_MachineCheck - _start + EXC_OFF_SYS_RESET
	li	r8, Alignment - _start + EXC_OFF_SYS_RESET
2:
	bl	trap_reloc
	addi	r7, r7, 0x100	    /* next exception vector	    */
	cmplw	0, r7, r8
	blt	2b

	li	r7, .L_Alignment - _start + EXC_OFF_SYS_RESET
	bl	trap_reloc

	li	r7, .L_ProgramCheck - _start + EXC_OFF_SYS_RESET
	bl	trap_reloc

	li	r7, .L_FPUnavailable - _start + EXC_OFF_SYS_RESET
	li	r8, SystemCall - _start + EXC_OFF_SYS_RESET
3:
	bl	trap_reloc
	addi	r7, r7, 0x100	    /* next exception vector	    */
	cmplw	0, r7, r8
	blt	3b

	li	r7, .L_SingleStep - _start + EXC_OFF_SYS_RESET
	li	r8, _end_of_vectors - _start + EXC_OFF_SYS_RESET
4:
	bl	trap_reloc
	addi	r7, r7, 0x100	    /* next exception vector	    */
	cmplw	0, r7, r8
	blt	4b

	mfmsr	r3		    /* now that the vectors have    */
	lis	r7, MSR_IP@h	    /* relocated into low memory    */
	ori	r7, r7, MSR_IP@l    /* MSR[IP] can be turned off    */
	andc	r3, r3, r7	    /* (if it was on)		    */
	SYNC			    /* Some chip revs need this...  */
	mtmsr	r3
	SYNC

	mtlr	r4		    /* restore link register	    */
	blr

	/*
	 * Function: relocate entries for one exception vector
	 */
trap_reloc:
	lwz	r0, 0(r7)	    /* hdlr ...			    */
	add	r0, r0, r3	    /*	... += dest_addr	    */
	stw	r0, 0(r7)

	lwz	r0, 4(r7)	    /* int_return ...		    */
	add	r0, r0, r3	    /*	... += dest_addr	    */
	stw	r0, 4(r7)

	blr
Commit	Line	Data
983fda83 WD	1	/*
	2	* Copyright (C) 1998 Dan Malek <[email protected]>
	3	* Copyright (C) 1999 Magnus Damm <kieraypc01.p.y.kie.era.ericsson.se>
	4	* Copyright (C) 2000 - 2003 Wolfgang Denk <[email protected]>
	5	*
	6	* See file CREDITS for list of people who contributed to this
	7	* project.
	8	*
	9	* This program is free software; you can redistribute it and/or
	10	* modify it under the terms of the GNU General Public License as
	11	* published by the Free Software Foundation; either version 2 of
	12	* the License, or (at your option) any later version.
	13	*
	14	* This program is distributed in the hope that it will be useful,
	15	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	16	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	17	* GNU General Public License for more details.
	18	*
	19	* You should have received a copy of the GNU General Public License
	20	* along with this program; if not, write to the Free Software
	21	* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
	22	* MA 02111-1307 USA
	23	*/
	24
	25	/*
	26	* U-Boot - Startup Code for MPC8220 CPUs
	27	*/
	28	#include <config.h>
	29	#include <mpc8220.h>
	30	#include <version.h>
	31
	32	#define _LINUX_CONFIG_H 1 /* avoid reading Linux autoconf.h file */
	33
	34	#include <ppc_asm.tmpl>
	35	#include <ppc_defs.h>
	36
	37	#include <asm/cache.h>
	38	#include <asm/mmu.h>
	39
	40	#ifndef CONFIG_IDENT_STRING
	41	#define CONFIG_IDENT_STRING ""
	42	#endif
	43
	44	/* We don't want the MMU yet.
	45	*/
	46	#undef MSR_KERNEL
	47	/* Floating Point enable, Machine Check and Recoverable Interr. */
	48	#ifdef DEBUG
	49	#define MSR_KERNEL (MSR_FP\|MSR_RI)
	50	#else
	51	#define MSR_KERNEL (MSR_FP\|MSR_ME\|MSR_RI)
	52	#endif
	53
	54	/*
	55	* Set up GOT: Global Offset Table
	56	*
	57	* Use r14 to access the GOT
	58	*/
	59	START_GOT
	60	GOT_ENTRY(_GOT2_TABLE_)
	61	GOT_ENTRY(_FIXUP_TABLE_)
	62
	63	GOT_ENTRY(_start)
	64	GOT_ENTRY(_start_of_vectors)
65	GOT_ENTRY(_end_of_vectors)
66	GOT_ENTRY(transfer_to_handler)
67
68	GOT_ENTRY(__init_end)
69	GOT_ENTRY(_end)
70	GOT_ENTRY(__bss_start)
71	END_GOT
72
73	/*
74	* Version string
75	*/
76	.data
77	.globl version_string
78	version_string:
79	.ascii U_BOOT_VERSION
80	.ascii " (", __DATE__, " - ", __TIME__, ")"
81	.ascii CONFIG_IDENT_STRING, "\0"
82
83	/*
84	* Exception vectors
85	*/
86	.text
87	. = EXC_OFF_SYS_RESET
88	.globl _start
89	_start:
90	li r21, BOOTFLAG_COLD /* Normal Power-On */
91	nop
92	b boot_cold
93
94	. = EXC_OFF_SYS_RESET + 0x10
95
96	.globl _start_warm
97	_start_warm:
98	li r21, BOOTFLAG_WARM /* Software reboot */
99	b boot_warm
100
101	boot_cold:
102	boot_warm:
103	mfmsr r5 /* save msr contents */
104
105	/* replace default MBAR base address from 0x80000000
106	to 0xf0000000 */
107
6d0f6bcf JCPV	108	#if defined(CONFIG_SYS_DEFAULT_MBAR) && !defined(CONFIG_SYS_RAMBOOT)
	109	lis r3, CONFIG_SYS_MBAR@h
	110	ori r3, r3, CONFIG_SYS_MBAR@l
983fda83 WD	111
	112	/* MBAR is mirrored into the MBAR SPR */
	113	mtspr MBAR,r3
3c2b3d45	114	mtspr SPRN_SPRG7W,r3
6d0f6bcf	115	lis r4, CONFIG_SYS_DEFAULT_MBAR@h
983fda83	116	stw r3, 0(r4)
6d0f6bcf	117	#endif /* CONFIG_SYS_DEFAULT_MBAR */
983fda83 WD	118
	119	/* Initialise the MPC8220 processor core */
	120	/--------------------------------------------------------------/
	121
	122	bl init_8220_core
	123
	124	/* initialize some things that are hard to access from C */
	125	/--------------------------------------------------------------/
	126
	127	/* set up stack in on-chip SRAM */
6d0f6bcf JCPV	128	lis r3, CONFIG_SYS_INIT_RAM_ADDR@h
	129	ori r3, r3, CONFIG_SYS_INIT_RAM_ADDR@l
	130	ori r1, r3, CONFIG_SYS_INIT_SP_OFFSET
983fda83 WD	131
	132	li r0, 0 /* Make room for stack frame header and */
	133	stwu r0, -4(r1) /* clear final stack frame so that */
	134	stwu r0, -4(r1) /* stack backtraces terminate cleanly */
	135
	136	/* let the C-code set up the rest */
	137	/* */
	138	/* Be careful to keep code relocatable ! */
	139	/--------------------------------------------------------------/
	140
	141	GET_GOT /* initialize GOT access */
	142
	143	/* r3: IMMR */
	144	bl cpu_init_f /* run low-level CPU init code (in Flash)*/
	145
	146	mr r3, r21
	147	/* r3: BOOTFLAG */
	148	bl board_init_f /* run 1st part of board init code (in Flash)*/
	149
	150	/*
	151	* Vector Table
	152	*/
	153
	154	.globl _start_of_vectors
	155	_start_of_vectors:
	156
	157	/* Machine check */
	158	STD_EXCEPTION(0x200, MachineCheck, MachineCheckException)
	159
	160	/* Data Storage exception. */
	161	STD_EXCEPTION(0x300, DataStorage, UnknownException)
	162
	163	/* Instruction Storage exception. */
	164	STD_EXCEPTION(0x400, InstStorage, UnknownException)
	165
	166	/* External Interrupt exception. */
	167	STD_EXCEPTION(0x500, ExtInterrupt, external_interrupt)
	168
	169	/* Alignment exception. */
	170	. = 0x600
	171	Alignment:
02032e8f	172	EXCEPTION_PROLOG(SRR0, SRR1)
983fda83 WD	173	mfspr r4,DAR
	174	stw r4,_DAR(r21)
	175	mfspr r5,DSISR
	176	stw r5,_DSISR(r21)
	177	addi r3,r1,STACK_FRAME_OVERHEAD
	178	li r20,MSR_KERNEL
	179	rlwimi r20,r23,0,16,16 /* copy EE bit from saved MSR */
	180	rlwimi r20,r23,0,25,25 /* copy IP bit from saved MSR */
	181	lwz r6,GOT(transfer_to_handler)
	182	mtlr r6
	183	blrl
	184	.L_Alignment:
	185	.long AlignmentException - _start + EXC_OFF_SYS_RESET
	186	.long int_return - _start + EXC_OFF_SYS_RESET
	187
	188	/* Program check exception */
	189	. = 0x700
	190	ProgramCheck:
02032e8f	191	EXCEPTION_PROLOG(SRR0, SRR1)
983fda83 WD	192	addi r3,r1,STACK_FRAME_OVERHEAD
	193	li r20,MSR_KERNEL
	194	rlwimi r20,r23,0,16,16 /* copy EE bit from saved MSR */
	195	rlwimi r20,r23,0,25,25 /* copy IP bit from saved MSR */
	196	lwz r6,GOT(transfer_to_handler)
	197	mtlr r6
	198	blrl
	199	.L_ProgramCheck:
	200	.long ProgramCheckException - _start + EXC_OFF_SYS_RESET
	201	.long int_return - _start + EXC_OFF_SYS_RESET
	202
	203	STD_EXCEPTION(0x800, FPUnavailable, UnknownException)
	204
	205	/* I guess we could implement decrementer, and may have
	206	* to someday for timekeeping.
	207	*/
	208	STD_EXCEPTION(0x900, Decrementer, timer_interrupt)
	209
	210	STD_EXCEPTION(0xa00, Trap_0a, UnknownException)
	211	STD_EXCEPTION(0xb00, Trap_0b, UnknownException)
	212	STD_EXCEPTION(0xc00, SystemCall, UnknownException)
	213	STD_EXCEPTION(0xd00, SingleStep, UnknownException)
	214
	215	STD_EXCEPTION(0xe00, Trap_0e, UnknownException)
	216	STD_EXCEPTION(0xf00, Trap_0f, UnknownException)
	217
	218	STD_EXCEPTION(0x1000, InstructionTLBMiss, UnknownException)
	219	STD_EXCEPTION(0x1100, DataLoadTLBMiss, UnknownException)
	220	STD_EXCEPTION(0x1200, DataStoreTLBMiss, UnknownException)
	221	#ifdef DEBUG
	222	. = 0x1300
	223	/*
	224	* This exception occurs when the program counter matches the
	225	* Instruction Address Breakpoint Register (IABR).
	226	*
	227	* I want the cpu to halt if this occurs so I can hunt around
	228	* with the debugger and look at things.
	229	*
	230	* When DEBUG is defined, both machine check enable (in the MSR)
	231	* and checkstop reset enable (in the reset mode register) are
	232	* turned off and so a checkstop condition will result in the cpu
	233	* halting.
	234	*
	235	* I force the cpu into a checkstop condition by putting an illegal
	236	* instruction here (at least this is the theory).
	237	*
	238	* well - that didnt work, so just do an infinite loop!
	239	*/
	240	1: b 1b
	241	#else
	242	STD_EXCEPTION(0x1300, InstructionBreakpoint, DebugException)
	243	#endif
	244	STD_EXCEPTION(0x1400, SMI, UnknownException)
	245
	246	STD_EXCEPTION(0x1500, Trap_15, UnknownException)
	247	STD_EXCEPTION(0x1600, Trap_16, UnknownException)
	248	STD_EXCEPTION(0x1700, Trap_17, UnknownException)
	249	STD_EXCEPTION(0x1800, Trap_18, UnknownException)
	250	STD_EXCEPTION(0x1900, Trap_19, UnknownException)
	251	STD_EXCEPTION(0x1a00, Trap_1a, UnknownException)
	252	STD_EXCEPTION(0x1b00, Trap_1b, UnknownException)
	253	STD_EXCEPTION(0x1c00, Trap_1c, UnknownException)
	254	STD_EXCEPTION(0x1d00, Trap_1d, UnknownException)
	255	STD_EXCEPTION(0x1e00, Trap_1e, UnknownException)
256	STD_EXCEPTION(0x1f00, Trap_1f, UnknownException)
257	STD_EXCEPTION(0x2000, Trap_20, UnknownException)
258	STD_EXCEPTION(0x2100, Trap_21, UnknownException)
259	STD_EXCEPTION(0x2200, Trap_22, UnknownException)
260	STD_EXCEPTION(0x2300, Trap_23, UnknownException)
261	STD_EXCEPTION(0x2400, Trap_24, UnknownException)
262	STD_EXCEPTION(0x2500, Trap_25, UnknownException)
263	STD_EXCEPTION(0x2600, Trap_26, UnknownException)
264	STD_EXCEPTION(0x2700, Trap_27, UnknownException)
265	STD_EXCEPTION(0x2800, Trap_28, UnknownException)
266	STD_EXCEPTION(0x2900, Trap_29, UnknownException)
267	STD_EXCEPTION(0x2a00, Trap_2a, UnknownException)
268	STD_EXCEPTION(0x2b00, Trap_2b, UnknownException)
269	STD_EXCEPTION(0x2c00, Trap_2c, UnknownException)
270	STD_EXCEPTION(0x2d00, Trap_2d, UnknownException)
271	STD_EXCEPTION(0x2e00, Trap_2e, UnknownException)
272	STD_EXCEPTION(0x2f00, Trap_2f, UnknownException)
273
274
275	.globl _end_of_vectors
276	_end_of_vectors:
277
278	. = 0x3000
279
280	/*
281	* This code finishes saving the registers to the exception frame
282	* and jumps to the appropriate handler for the exception.
283	* Register r21 is pointer into trap frame, r1 has new stack pointer.
284	*/
285	.globl transfer_to_handler
286	transfer_to_handler:
287	stw r22,_NIP(r21)
288	lis r22,MSR_POW@h
289	andc r23,r23,r22
290	stw r23,_MSR(r21)
291	SAVE_GPR(7, r21)
292	SAVE_4GPRS(8, r21)
293	SAVE_8GPRS(12, r21)
294	SAVE_8GPRS(24, r21)
295	mflr r23
296	andi. r24,r23,0x3f00 /* get vector offset */
297	stw r24,TRAP(r21)
298	li r22,0
299	stw r22,RESULT(r21)
300	lwz r24,0(r23) /* virtual address of handler */
301	lwz r23,4(r23) /* where to go when done */
302	mtspr SRR0,r24
303	mtspr SRR1,r20
304	mtlr r23
305	SYNC
306	rfi /* jump to handler, enable MMU */
307
308	int_return:
309	mfmsr r28 /* Disable interrupts */
310	li r4,0
311	ori r4,r4,MSR_EE
312	andc r28,r28,r4
313	SYNC /* Some chip revs need this... */
314	mtmsr r28
315	SYNC
316	lwz r2,_CTR(r1)
317	lwz r0,_LINK(r1)
318	mtctr r2
319	mtlr r0
320	lwz r2,_XER(r1)
321	lwz r0,_CCR(r1)
322	mtspr XER,r2
323	mtcrf 0xFF,r0
324	REST_10GPRS(3, r1)
325	REST_10GPRS(13, r1)
326	REST_8GPRS(23, r1)
327	REST_GPR(31, r1)
328	lwz r2,_NIP(r1) /* Restore environment */
329	lwz r0,_MSR(r1)
330	mtspr SRR0,r2
331	mtspr SRR1,r0
332	lwz r0,GPR0(r1)
333	lwz r2,GPR2(r1)
334	lwz r1,GPR1(r1)
335	SYNC
336	rfi
337
338	/*
339	* This code initialises the MPC8220 processor core
340	* (conforms to PowerPC 603e spec)
341	* Note: expects original MSR contents to be in r5.
342	*/
343
344	.globl init_8220_core
345	init_8220_core:
346
347	/* Initialize machine status; enable machine check interrupt */
348	/--------------------------------------------------------------/
349
350	li r3, MSR_KERNEL /* Set ME and RI flags */
351	rlwimi r3, r5, 0, 25, 25 /* preserve IP bit set by HRCW */
352	#ifdef DEBUG
353	rlwimi r3, r5, 0, 21, 22 /* debugger might set SE & BE bits */
354	#endif
355	SYNC /* Some chip revs need this... */
356	mtmsr r3
357	SYNC
358	mtspr SRR1, r3 /* Make SRR1 match MSR */
359
360	/* Initialize the Hardware Implementation-dependent Registers */
361	/* HID0 also contains cache control */
362	/--------------------------------------------------------------/
363
6d0f6bcf JCPV	364	lis r3, CONFIG_SYS_HID0_INIT@h
6d0f6bcf JCPV	365	ori r3, r3, CONFIG_SYS_HID0_INIT@l
983fda83 WD	366	SYNC
	367	mtspr HID0, r3
	368
6d0f6bcf JCPV	369	lis r3, CONFIG_SYS_HID0_FINAL@h
6d0f6bcf JCPV	370	ori r3, r3, CONFIG_SYS_HID0_FINAL@l
983fda83 WD	371	SYNC
	372	mtspr HID0, r3
	373
	374	/* Enable Extra BATs */
	375	mfspr r3, 1011 /* HID2 */
	376	lis r4, 0x0004
	377	ori r4, r4, 0x0000
	378	or r4, r4, r3
	379	mtspr 1011, r4
	380	sync
	381
	382	/* clear all BAT's */
	383	/--------------------------------------------------------------/
	384
	385	li r0, 0
	386	mtspr DBAT0U, r0
	387	mtspr DBAT0L, r0
	388	mtspr DBAT1U, r0
	389	mtspr DBAT1L, r0
	390	mtspr DBAT2U, r0
	391	mtspr DBAT2L, r0
	392	mtspr DBAT3U, r0
	393	mtspr DBAT3L, r0
	394	mtspr DBAT4U, r0
	395	mtspr DBAT4L, r0
	396	mtspr DBAT5U, r0
	397	mtspr DBAT5L, r0
	398	mtspr DBAT6U, r0
	399	mtspr DBAT6L, r0
	400	mtspr DBAT7U, r0
	401	mtspr DBAT7L, r0
	402	mtspr IBAT0U, r0
	403	mtspr IBAT0L, r0
	404	mtspr IBAT1U, r0
	405	mtspr IBAT1L, r0
	406	mtspr IBAT2U, r0
	407	mtspr IBAT2L, r0
	408	mtspr IBAT3U, r0
	409	mtspr IBAT3L, r0
	410	mtspr IBAT4U, r0
	411	mtspr IBAT4L, r0
	412	mtspr IBAT5U, r0
	413	mtspr IBAT5L, r0
	414	mtspr IBAT6U, r0
	415	mtspr IBAT6L, r0
	416	mtspr IBAT7U, r0
	417	mtspr IBAT7L, r0
	418	SYNC
	419
	420	/* invalidate all tlb's */
	421	/* */
	422	/* From the 603e User Manual: "The 603e provides the ability to */
	423	/* invalidate a TLB entry. The TLB Invalidate Entry (tlbie) */
	424	/* instruction invalidates the TLB entry indexed by the EA, and */
	425	/* operates on both the instruction and data TLBs simultaneously*/
	426	/* invalidating four TLB entries (both sets in each TLB). The */
	427	/* index corresponds to bits 15-19 of the EA. To invalidate all */
	428	/* entries within both TLBs, 32 tlbie instructions should be */
	429	/* issued, incrementing this field by one each time." */
	430	/* */
	431	/* "Note that the tlbia instruction is not implemented on the */
	432	/* 603e." */
	433	/* */
	434	/* bits 15-19 correspond to addresses 0x00000000 to 0x0001F000 */
435	/* incrementing by 0x1000 each time. The code below is sort of */
436	/* based on code in "flush_tlbs" from arch/ppc/kernel/head.S */
437	/* */
438	/--------------------------------------------------------------/
439
440	li r3, 32
441	mtctr r3
442	li r3, 0
443	1: tlbie r3
444	addi r3, r3, 0x1000
445	bdnz 1b
446	SYNC
447
448	/* Done! */
449	/--------------------------------------------------------------/
450
451	blr
452
453	/* Cache functions.
454	*
455	* Note: requires that all cache bits in
456	* HID0 are in the low half word.
457	*/
458	.globl icache_enable
459	icache_enable:
460	lis r4, 0
6d0f6bcf	461	ori r4, r4, CONFIG_SYS_HID0_INIT /* set ICE & ICFI bit */
983fda83 WD	462	rlwinm r3, r4, 0, 21, 19 /* clear the ICFI bit */
	463
	464	/*
	465	* The setting of the instruction cache enable (ICE) bit must be
	466	* preceded by an isync instruction to prevent the cache from being
	467	* enabled or disabled while an instruction access is in progress.
	468	*/
	469	isync
	470	mtspr HID0, r4 /* Enable Instr Cache & Inval cache */
	471	mtspr HID0, r3 /* using 2 consec instructions */
	472	isync
	473	blr
	474
	475	.globl icache_disable
	476	icache_disable:
	477	mfspr r3, HID0
	478	rlwinm r3, r3, 0, 17, 15 /* clear the ICE bit */
	479	mtspr HID0, r3
	480	isync
	481	blr
	482
	483	.globl icache_status
	484	icache_status:
	485	mfspr r3, HID0
	486	rlwinm r3, r3, HID0_ICE_BITPOS + 1, 31, 31
	487	blr
	488
	489	.globl dcache_enable
	490	dcache_enable:
	491	lis r4, 0
	492	ori r4, r4, HID0_DCE\|HID0_DCFI /* set DCE & DCFI bit */
	493	rlwinm r3, r4, 0, 22, 20 /* clear the DCFI bit */
	494
	495	/* Enable address translation in MSR bit */
	496	mfmsr r5
	497	ori r5, r5, 0x
	498
	499
	500	/*
	501	* The setting of the instruction cache enable (ICE) bit must be
	502	* preceded by an isync instruction to prevent the cache from being
	503	* enabled or disabled while an instruction access is in progress.
	504	*/
	505	isync
	506	mtspr HID0, r4 /* Enable Data Cache & Inval cache*/
	507	mtspr HID0, r3 /* using 2 consec instructions */
	508	isync
	509	blr
	510
	511	.globl dcache_disable
	512	dcache_disable:
	513	mfspr r3, HID0
	514	rlwinm r3, r3, 0, 18, 16 /* clear the DCE bit */
	515	mtspr HID0, r3
	516	isync
	517	blr
	518
	519	.globl dcache_status
	520	dcache_status:
	521	mfspr r3, HID0
	522	rlwinm r3, r3, HID0_DCE_BITPOS + 1, 31, 31
	523	blr
	524
	525	.globl get_pvr
526	get_pvr:
527	mfspr r3, PVR
528	blr
529
530	/------------------------------------------------------------------------------/
531
532	/*
533	* void relocate_code (addr_sp, gd, addr_moni)
534	*
535	* This "function" does not return, instead it continues in RAM
536	* after relocating the monitor code.
537	*
538	* r3 = dest
539	* r4 = src
540	* r5 = length in bytes
541	* r6 = cachelinesize
542	*/
543	.globl relocate_code
544	relocate_code:
545	mr r1, r3 /* Set new stack pointer */
546	mr r9, r4 /* Save copy of Global Data pointer */
547	mr r10, r5 /* Save copy of Destination Address */
548
549	mr r3, r5 /* Destination Address */
6d0f6bcf JCPV	550	lis r4, CONFIG_SYS_MONITOR_BASE@h /* Source Address */
6d0f6bcf JCPV	551	ori r4, r4, CONFIG_SYS_MONITOR_BASE@l
983fda83 WD	552	lwz r5, GOT(__init_end)
983fda83 WD	553	sub r5, r5, r4
6d0f6bcf	554	li r6, CONFIG_SYS_CACHELINE_SIZE /* Cache Line Size */
983fda83 WD	555
	556	/*
	557	* Fix GOT pointer:
	558	*
6d0f6bcf	559	* New GOT-PTR = (old GOT-PTR - CONFIG_SYS_MONITOR_BASE) + Destination Address
983fda83 WD	560	*
	561	* Offset:
	562	*/
	563	sub r15, r10, r4
	564
	565	/* First our own GOT */
	566	add r14, r14, r15
	567	/* then the one used by the C code */
	568	add r30, r30, r15
	569
	570	/*
	571	* Now relocate code
	572	*/
	573
	574	cmplw cr1,r3,r4
	575	addi r0,r5,3
	576	srwi. r0,r0,2
	577	beq cr1,4f /* In place copy is not necessary */
	578	beq 7f /* Protect against 0 count */
	579	mtctr r0
	580	bge cr1,2f
	581
	582	la r8,-4(r4)
	583	la r7,-4(r3)
	584	1: lwzu r0,4(r8)
	585	stwu r0,4(r7)
	586	bdnz 1b
	587	b 4f
	588
	589	2: slwi r0,r0,2
	590	add r8,r4,r0
	591	add r7,r3,r0
	592	3: lwzu r0,-4(r8)
	593	stwu r0,-4(r7)
	594	bdnz 3b
	595
	596	/*
	597	* Now flush the cache: note that we must start from a cache aligned
	598	* address. Otherwise we might miss one cache line.
	599	*/
	600	4: cmpwi r6,0
	601	add r5,r3,r5
	602	beq 7f /* Always flush prefetch queue in any case */
	603	subi r0,r6,1
	604	andc r3,r3,r0
	605	mfspr r7,HID0 /* don't do dcbst if dcache is disabled */
	606	rlwinm r7,r7,HID0_DCE_BITPOS+1,31,31
	607	cmpwi r7,0
	608	beq 9f
	609	mr r4,r3
	610	5: dcbst 0,r4
	611	add r4,r4,r6
	612	cmplw r4,r5
	613	blt 5b
	614	sync /* Wait for all dcbst to complete on bus */
	615	9: mfspr r7,HID0 /* don't do icbi if icache is disabled */
	616	rlwinm r7,r7,HID0_ICE_BITPOS+1,31,31
	617	cmpwi r7,0
	618	beq 7f
	619	mr r4,r3
	620	6: icbi 0,r4
	621	add r4,r4,r6
	622	cmplw r4,r5
	623	blt 6b
624	7: sync /* Wait for all icbi to complete on bus */
625	isync
626
627	/*
628	* We are done. Do not return, instead branch to second part of board
629	* initialization, now running from RAM.
630	*/
631
632	addi r0, r10, in_ram - _start + EXC_OFF_SYS_RESET
633	mtlr r0
634	blr
635
636	in_ram:
637
638	/*
639	* Relocation Function, r14 point to got2+0x8000
640	*
641	* Adjust got2 pointers, no need to check for 0, this code
642	* already puts a few entries in the table.
643	*/
644	li r0,__got2_entries@sectoff@l
645	la r3,GOT(_GOT2_TABLE_)
646	lwz r11,GOT(_GOT2_TABLE_)
647	mtctr r0
648	sub r11,r3,r11
649	addi r3,r3,-4
650	1: lwzu r0,4(r3)
651	add r0,r0,r11
652	stw r0,0(r3)
653	bdnz 1b
654
655	/*
656	* Now adjust the fixups and the pointers to the fixups
657	* in case we need to move ourselves again.
658	*/
659	2: li r0,__fixup_entries@sectoff@l
660	lwz r3,GOT(_FIXUP_TABLE_)
661	cmpwi r0,0
662	mtctr r0
663	addi r3,r3,-4
664	beq 4f
665	3: lwzu r4,4(r3)
666	lwzux r0,r4,r11
667	add r0,r0,r11
668	stw r10,0(r3)
669	stw r0,0(r4)
670	bdnz 3b
671	4:
672	clear_bss:
673	/*
674	* Now clear BSS segment
675	*/
676	lwz r3,GOT(__bss_start)
677	lwz r4,GOT(_end)
678
679	cmplw 0, r3, r4
680	beq 6f
681
682	li r0, 0
683	5:
684	stw r0, 0(r3)
685	addi r3, r3, 4
686	cmplw 0, r3, r4
687	bne 5b
688	6:
689
690	mr r3, r9 /* Global Data pointer */
691	mr r4, r10 /* Destination Address */
692	bl board_init_r
693
694	/*
695	* Copy exception vector code to low memory
696	*
697	* r3: dest_addr
698	* r7: source address, r8: end address, r9: target address
699	*/
700	.globl trap_init
701	trap_init:
702	lwz r7, GOT(_start)
703	lwz r8, GOT(_end_of_vectors)
704
705	li r9, 0x100 /* reset vector always at 0x100 */
706
707	cmplw 0, r7, r8
708	bgelr /* return if r7>=r8 - just in case */
709
710	mflr r4 /* save link register */
711	1:
712	lwz r0, 0(r7)
713	stw r0, 0(r9)
714	addi r7, r7, 4
715	addi r9, r9, 4
716	cmplw 0, r7, r8
717	bne 1b
718
719	/*
720	* relocate `hdlr' and `int_return' entries
721	*/
722	li r7, .L_MachineCheck - _start + EXC_OFF_SYS_RESET
723	li r8, Alignment - _start + EXC_OFF_SYS_RESET
724	2:
725	bl trap_reloc
726	addi r7, r7, 0x100 /* next exception vector */
727	cmplw 0, r7, r8
728	blt 2b
729
730	li r7, .L_Alignment - _start + EXC_OFF_SYS_RESET
731	bl trap_reloc
732
733	li r7, .L_ProgramCheck - _start + EXC_OFF_SYS_RESET
734	bl trap_reloc
735
736	li r7, .L_FPUnavailable - _start + EXC_OFF_SYS_RESET
737	li r8, SystemCall - _start + EXC_OFF_SYS_RESET
738	3:
739	bl trap_reloc
740	addi r7, r7, 0x100 /* next exception vector */
741	cmplw 0, r7, r8
742	blt 3b
743
744	li r7, .L_SingleStep - _start + EXC_OFF_SYS_RESET
745	li r8, _end_of_vectors - _start + EXC_OFF_SYS_RESET
746	4:
747	bl trap_reloc
748	addi r7, r7, 0x100 /* next exception vector */
749	cmplw 0, r7, r8
750	blt 4b
751
752	mfmsr r3 /* now that the vectors have */
753	lis r7, MSR_IP@h /* relocated into low memory */
754	ori r7, r7, MSR_IP@l /* MSR[IP] can be turned off */
755	andc r3, r3, r7 /* (if it was on) */
756	SYNC /* Some chip revs need this... */
757	mtmsr r3
758	SYNC
759
760	mtlr r4 /* restore link register */
761	blr
762
763	/*
764	* Function: relocate entries for one exception vector
765	*/
766	trap_reloc:
767	lwz r0, 0(r7) /* hdlr ... */
768	add r0, r0, r3 /* ... += dest_addr */
769	stw r0, 0(r7)
770
771	lwz r0, 4(r7) /* int_return ... */
772	add r0, r0, r3 /* ... += dest_addr */
773	stw r0, 4(r7)
774
775	blr