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authorwdenk <wdenk>2002-11-03 00:01:44 +0000
committerwdenk <wdenk>2002-11-03 00:01:44 +0000
commit47d1a6e1ed87fe1fb3d737acdb85f69bc3259522 (patch)
treebcf85bebad1b0b31392a84a649595beacaa57ab1 /cpu/74xx_7xx/start.S
parente221174377d7e3ee848e014b96430d4c97023e93 (diff)
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+/*
+ * Copyright (C) 1998 Dan Malek <dmalek@jlc.net>
+ * Copyright (C) 1999 Magnus Damm <kieraypc01.p.y.kie.era.ericsson.se>
+ * Copyright (C) 2000,2001,2002 Wolfgang Denk <wd@denx.de>
+ * Copyright (C) 2001 Josh Huber <huber@mclx.com>
+ *
+ * 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 PowerPC based Embedded Boards
+ *
+ *
+ * The processor starts at 0xfff00100 and the code is executed
+ * from flash. The code is organized to be at an other address
+ * 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.
+ */
+#include <config.h>
+#include <74xx_7xx.h>
+#include <version.h>
+
+#include <ppc_asm.tmpl>
+#include <ppc_defs.h>
+
+#include <asm/cache.h>
+#include <asm/mmu.h>
+
+#include <galileo/gt64260R.h>
+
+#ifndef CONFIG_IDENT_STRING
+#define CONFIG_IDENT_STRING ""
+#endif
+
+/* We don't want the MMU yet.
+*/
+#undef MSR_KERNEL
+/* Machine Check and Recoverable Interr. */
+#define MSR_KERNEL ( MSR_ME | MSR_RI )
+
+/*
+ * 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
+
+/*
+ * 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"
+
+ . = EXC_OFF_SYS_RESET
+ .globl _start
+_start:
+ li r21, BOOTFLAG_COLD /* Normal Power-On: Boot from FLASH */
+ b boot_cold
+ sync
+
+ . = EXC_OFF_SYS_RESET + 0x10
+
+ .globl _start_warm
+_start_warm:
+ li r21, BOOTFLAG_WARM /* Software reboot */
+ b boot_warm
+ sync
+
+ /* the boot code is located below the exception table */
+
+ .globl _start_of_vectors
+_start_of_vectors:
+
+/* Machine check */
+ STD_EXCEPTION(0x200, MachineCheck, MachineCheckException)
+
+/* Data Storage exception. "Never" generated on the 860. */
+ STD_EXCEPTION(0x300, DataStorage, UnknownException)
+
+/* Instruction Storage exception. "Never" generated on the 860. */
+ 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, SoftEmu, SoftEmuException)
+
+ 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)
+
+ .globl _end_of_vectors
+_end_of_vectors:
+
+ . = 0x2000
+
+boot_cold:
+boot_warm:
+ /* disable everything */
+ li r0, 0
+ mtspr HID0, r0
+ sync
+ mtmsr 0
+ bl invalidate_bats
+ sync
+
+#ifdef CFG_L2
+ /* init the L2 cache */
+ addis r3, r0, L2_INIT@h
+ ori r3, r3, L2_INIT@l
+ sync
+ mtspr l2cr, r3
+#endif
+#if defined(CONFIG_ALTIVEC) && defined(CONFIG_74xx)
+ .long 0x7e00066c
+ /*
+ * dssall instruction, gas doesn't have it yet
+ * ...for altivec, data stream stop all this probably
+ * isn't needed unless we warm (software) reboot U-Boot
+ */
+#endif
+
+#ifdef CFG_L2
+ /* invalidate the L2 cache */
+ bl l2cache_invalidate
+ sync
+#endif
+#ifdef CFG_BOARD_ASM_INIT
+ /* do early init */
+ bl board_asm_init
+#endif
+
+ /*
+ * Calculate absolute address in FLASH and jump there
+ *------------------------------------------------------*/
+ lis r3, CFG_MONITOR_BASE@h
+ ori r3, r3, CFG_MONITOR_BASE@l
+ addi r3, r3, in_flash - _start + EXC_OFF_SYS_RESET
+ mtlr r3
+ blr
+
+in_flash:
+ /* let the C-code set up the rest */
+ /* */
+ /* Be careful to keep code relocatable ! */
+ /*------------------------------------------------------*/
+
+ /* perform low-level init */
+ /* sdram init, galileo init, etc */
+ /* r3: NHR bit from HID0 */
+
+ /* setup the bats */
+ bl setup_bats
+ sync
+
+ /*
+ * Cache must be enabled here for stack-in-cache trick.
+ * This means we need to enable the BATS.
+ * This means:
+ * 1) for the EVB, original gt regs need to be mapped
+ * 2) need to have an IBAT for the 0xf region,
+ * we are running there!
+ * Cache should be turned on after BATs, since by default
+ * everything is write-through.
+ * The init-mem BAT can be reused after reloc. The old
+ * gt-regs BAT can be reused after board_init_f calls
+ * board_pre_init (EVB only).
+ */
+#if !defined(CONFIG_BAB7xx) && !defined(CONFIG_ELPPC)
+ /* enable address translation */
+ bl enable_addr_trans
+ sync
+
+ /* enable and invalidate the data cache */
+ bl l1dcache_enable
+ sync
+#endif
+#ifdef CFG_INIT_RAM_LOCK
+ bl lock_ram_in_cache
+ sync
+#endif
+
+ /* set up the stack pointer in our newly created
+ * cache-ram (r1) */
+ lis r1, (CFG_INIT_RAM_ADDR + CFG_GBL_DATA_OFFSET)@h
+ ori r1, r1, (CFG_INIT_RAM_ADDR + CFG_GBL_DATA_OFFSET)@l
+
+ li r0, 0 /* Make room for stack frame header and */
+ stwu r0, -4(r1) /* clear final stack frame so that */
+ stwu r0, -4(r1) /* stack backtraces terminate cleanly */
+
+ GET_GOT /* initialize GOT access */
+
+ /* run low-level CPU init code (from Flash) */
+ bl cpu_init_f
+ sync
+
+ mr r3, r21
+
+ /* r3: BOOTFLAG */
+ /* run 1st part of board init code (from Flash) */
+ bl board_init_f
+ sync
+
+ /* NOTREACHED */
+
+ .globl invalidate_bats
+invalidate_bats:
+ /* invalidate BATs */
+ mtspr IBAT0U, r0
+ mtspr IBAT1U, r0
+ mtspr IBAT2U, r0
+ mtspr IBAT3U, r0
+ isync
+ mtspr DBAT0U, r0
+ mtspr DBAT1U, r0
+ mtspr DBAT2U, r0
+ mtspr DBAT3U, r0
+ isync
+ sync
+ blr
+
+ /* setup_bats - set them up to some initial state */
+ .globl setup_bats
+setup_bats:
+ addis r0, r0, 0x0000
+
+ /* IBAT 0 */
+ addis r4, r0, CFG_IBAT0L@h
+ ori r4, r4, CFG_IBAT0L@l
+ addis r3, r0, CFG_IBAT0U@h
+ ori r3, r3, CFG_IBAT0U@l
+ mtspr IBAT0L, r4
+ mtspr IBAT0U, r3
+ isync
+
+ /* DBAT 0 */
+ addis r4, r0, CFG_DBAT0L@h
+ ori r4, r4, CFG_DBAT0L@l
+ addis r3, r0, CFG_DBAT0U@h
+ ori r3, r3, CFG_DBAT0U@l
+ mtspr DBAT0L, r4
+ mtspr DBAT0U, r3
+ isync
+
+ /* IBAT 1 */
+ addis r4, r0, CFG_IBAT1L@h
+ ori r4, r4, CFG_IBAT1L@l
+ addis r3, r0, CFG_IBAT1U@h
+ ori r3, r3, CFG_IBAT1U@l
+ mtspr IBAT1L, r4
+ mtspr IBAT1U, r3
+ isync
+
+ /* DBAT 1 */
+ addis r4, r0, CFG_DBAT1L@h
+ ori r4, r4, CFG_DBAT1L@l
+ addis r3, r0, CFG_DBAT1U@h
+ ori r3, r3, CFG_DBAT1U@l
+ mtspr DBAT1L, r4
+ mtspr DBAT1U, r3
+ isync
+
+ /* IBAT 2 */
+ addis r4, r0, CFG_IBAT2L@h
+ ori r4, r4, CFG_IBAT2L@l
+ addis r3, r0, CFG_IBAT2U@h
+ ori r3, r3, CFG_IBAT2U@l
+ mtspr IBAT2L, r4
+ mtspr IBAT2U, r3
+ isync
+
+ /* DBAT 2 */
+ addis r4, r0, CFG_DBAT2L@h
+ ori r4, r4, CFG_DBAT2L@l
+ addis r3, r0, CFG_DBAT2U@h
+ ori r3, r3, CFG_DBAT2U@l
+ mtspr DBAT2L, r4
+ mtspr DBAT2U, r3
+ isync
+
+ /* IBAT 3 */
+ addis r4, r0, CFG_IBAT3L@h
+ ori r4, r4, CFG_IBAT3L@l
+ addis r3, r0, CFG_IBAT3U@h
+ ori r3, r3, CFG_IBAT3U@l
+ mtspr IBAT3L, r4
+ mtspr IBAT3U, r3
+ isync
+
+ /* DBAT 3 */
+ addis r4, r0, CFG_DBAT3L@h
+ ori r4, r4, CFG_DBAT3L@l
+ addis r3, r0, CFG_DBAT3U@h
+ ori r3, r3, CFG_DBAT3U@l
+ mtspr DBAT3L, r4
+ mtspr DBAT3U, r3
+ isync
+
+ /* bats are done, now invalidate the TLBs */
+
+ addis r3, 0, 0x0000
+ addis r5, 0, 0x4 /* upper bound of 0x00040000 for 7400/750 */
+
+ isync
+
+tlblp:
+ tlbie r3
+ sync
+ addi r3, r3, 0x1000
+ cmp 0, 0, r3, r5
+ blt tlblp
+
+ blr
+
+ .globl enable_addr_trans
+enable_addr_trans:
+ /* enable address translation */
+ mfmsr r5
+ ori r5, r5, (MSR_IR | MSR_DR)
+ mtmsr r5
+ isync
+ blr
+
+ .globl disable_addr_trans
+disable_addr_trans:
+ /* disable address translation */
+ mflr r4
+ mfmsr r3
+ andi. r0, r3, (MSR_IR | MSR_DR)
+ beqlr
+ andc r3, r3, r0
+ mtspr SRR0, r4
+ mtspr SRR1, r3
+ rfi
+
+/*
+ * 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)
+ mtspr SPRG2,r22 /* r1 is now kernel sp */
+ 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
+
+ .globl dc_read
+dc_read:
+ blr
+
+ .globl get_pvr
+get_pvr:
+ mfspr r3, PVR
+ blr
+
+/*-----------------------------------------------------------------------*/
+/*
+ * void relocate_code (addr_sp, gd, addr_moni)
+ *
+ * This "function" does not return, instead it continues in RAM
+ * after relocating the monitor code.
+ *
+ * r3 = dest
+ * r4 = src
+ * r5 = length in bytes
+ * r6 = cachelinesize
+ */
+ .globl relocate_code
+relocate_code:
+ mr r1, r3 /* Set new stack pointer */
+ mr r9, r4 /* Save copy of Global Data pointer */
+ mr r10, r5 /* Save copy of Destination Address */
+
+ mr r3, r5 /* Destination Address */
+ lis r4, CFG_MONITOR_BASE@h /* Source Address */
+ ori r4, r4, CFG_MONITOR_BASE@l
+ 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
+ /* then the one used by the C code */
+ add r30, r30, r15
+
+ /*
+ * Now relocate code
+ */
+#ifdef CONFIG_ECC
+ bl board_relocate_rom
+ sync
+ mr r3, r10 /* 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 */
+#else
+ 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
+#endif
+/*
+ * 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
+
+in_ram:
+#ifdef CONFIG_ECC
+ bl board_init_ecc
+#endif
+ /*
+ * 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, r10 /* Destination Address */
+ bl after_reloc
+
+ /* not reached - end relocate_code */
+/*-----------------------------------------------------------------------*/
+
+ /* 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
+
+ /* enable execptions from RAM vectors */
+ mfmsr r7
+ li r8,MSR_IP
+ andc r7,r7,r8
+ mtmsr r7
+
+ 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)
+
+ sync
+ isync
+
+ blr
+
+#ifdef CFG_INIT_RAM_LOCK
+lock_ram_in_cache:
+ /* Allocate Initial RAM in data cache.
+ */
+ lis r3, (CFG_INIT_RAM_ADDR & ~31)@h
+ ori r3, r3, (CFG_INIT_RAM_ADDR & ~31)@l
+ li r2, ((CFG_INIT_RAM_END & ~31) + \
+ (CFG_INIT_RAM_ADDR & 31) + 31) / 32
+ mtctr r2
+1:
+ dcbz r0, r3
+ addi r3, r3, 32
+ bdnz 1b
+
+ /* Lock the data cache */
+ mfspr r0, HID0
+ ori r0, r0, 0x1000
+ sync
+ mtspr HID0, r0
+ sync
+ blr
+
+.globl unlock_ram_in_cache
+unlock_ram_in_cache:
+ /* invalidate the INIT_RAM section */
+ lis r3, (CFG_INIT_RAM_ADDR & ~31)@h
+ ori r3, r3, (CFG_INIT_RAM_ADDR & ~31)@l
+ li r2, ((CFG_INIT_RAM_END & ~31) + \
+ (CFG_INIT_RAM_ADDR & 31) + 31) / 32
+ mtctr r2
+1: icbi r0, r3
+ addi r3, r3, 32
+ bdnz 1b
+ sync /* Wait for all icbi to complete on bus */
+ isync
+
+ /* Unlock the data cache and invalidate it */
+ mfspr r0, HID0
+ li r3,0x1000
+ andc r0,r0,r3
+ li r3,0x0400
+ or r0,r0,r3
+ sync
+ mtspr HID0, r0
+ sync
+ blr
+#endif