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+/*
+ * (C) Copyright 2011, Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
+ * (C) Copyright 2011, Julius Baxter <julius@opencores.org>
+ *
+ * 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
+ */
+
+#include <config.h>
+#include <asm-offsets.h>
+#include <asm/spr-defs.h>
+
+#define EXCEPTION_STACK_SIZE (128+128)
+
+#define HANDLE_EXCEPTION \
+ l.addi r1, r1, -EXCEPTION_STACK_SIZE ;\
+ l.sw 0x1c(r1), r9 ;\
+ l.jal _exception_handler ;\
+ l.nop ;\
+ l.lwz r9, 0x1c(r1) ;\
+ l.addi r1, r1, EXCEPTION_STACK_SIZE ;\
+ l.rfe ;\
+ l.nop
+
+ .section .vectors, "ax"
+ .global __reset
+
+ /* reset */
+ .org 0x100
+__reset:
+ /* there is no guarantee r0 is hardwired to zero, clear it here */
+ l.andi r0, r0, 0
+ /* reset stack and frame pointers */
+ l.andi r1, r0, 0
+ l.andi r2, r0, 0
+
+ /* set supervisor mode */
+ l.ori r3,r0,SPR_SR_SM
+ l.mtspr r0,r3,SPR_SR
+
+ /* Relocate u-boot */
+ l.movhi r3,hi(__start) /* source start address */
+ l.ori r3,r3,lo(__start)
+ l.movhi r4,hi(_stext) /* dest start address */
+ l.ori r4,r4,lo(_stext)
+ l.movhi r5,hi(__end) /* dest end address */
+ l.ori r5,r5,lo(__end)
+
+.L_reloc:
+ l.lwz r6,0(r3)
+ l.sw 0(r4),r6
+ l.addi r3,r3,4
+ l.sfltu r4,r5
+ l.bf .L_reloc
+ l.addi r4,r4,4 /* delay slot */
+
+#ifdef CONFIG_SYS_RELOCATE_VECTORS
+ /* Relocate vectors from 0xf0000000 to 0x00000000 */
+ l.movhi r4, 0xf000 /* source */
+ l.movhi r5, 0 /* destination */
+ l.addi r6, r5, CONFIG_SYS_VECTORS_LEN /* length */
+.L_relocvectors:
+ l.lwz r7, 0(r4)
+ l.sw 0(r5), r7
+ l.addi r5, r5, 4
+ l.sfeq r5,r6
+ l.bnf .L_relocvectors
+ l.addi r4,r4, 4
+#endif
+
+ l.j _start
+ l.nop
+
+ /* bus error */
+ .org 0x200
+ HANDLE_EXCEPTION
+
+ /* data page fault */
+ .org 0x300
+ HANDLE_EXCEPTION
+
+ /* instruction page fault */
+ .org 0x400
+ HANDLE_EXCEPTION
+
+ /* tick timer */
+ .org 0x500
+ HANDLE_EXCEPTION
+
+ /* alignment */
+ .org 0x600
+ HANDLE_EXCEPTION
+
+ /* illegal instruction */
+ .org 0x700
+ HANDLE_EXCEPTION
+
+ /* external interrupt */
+ .org 0x800
+ HANDLE_EXCEPTION
+
+ /* D-TLB miss */
+ .org 0x900
+ HANDLE_EXCEPTION
+
+ /* I-TLB miss */
+ .org 0xa00
+ HANDLE_EXCEPTION
+
+ /* range */
+ .org 0xb00
+ HANDLE_EXCEPTION
+
+ /* system call */
+ .org 0xc00
+ HANDLE_EXCEPTION
+
+ /* floating point */
+ .org 0xd00
+ HANDLE_EXCEPTION
+
+ /* trap */
+ .org 0xe00
+ HANDLE_EXCEPTION
+
+ /* reserved */
+ .org 0xf00
+ HANDLE_EXCEPTION
+
+ /* reserved */
+ .org 0x1100
+ HANDLE_EXCEPTION
+
+ /* reserved */
+ .org 0x1200
+ HANDLE_EXCEPTION
+
+ /* reserved */
+ .org 0x1300
+ HANDLE_EXCEPTION
+
+ /* reserved */
+ .org 0x1400
+ HANDLE_EXCEPTION
+
+ /* reserved */
+ .org 0x1500
+ HANDLE_EXCEPTION
+
+ /* reserved */
+ .org 0x1600
+ HANDLE_EXCEPTION
+
+ /* reserved */
+ .org 0x1700
+ HANDLE_EXCEPTION
+
+ /* reserved */
+ .org 0x1800
+ HANDLE_EXCEPTION
+
+ /* reserved */
+ .org 0x1900
+ HANDLE_EXCEPTION
+
+ /* reserved */
+ .org 0x1a00
+ HANDLE_EXCEPTION
+
+ /* reserved */
+ .org 0x1b00
+ HANDLE_EXCEPTION
+
+ /* reserved */
+ .org 0x1c00
+ HANDLE_EXCEPTION
+
+ /* reserved */
+ .org 0x1d00
+ HANDLE_EXCEPTION
+
+ /* reserved */
+ .org 0x1e00
+ HANDLE_EXCEPTION
+
+ /* reserved */
+ .org 0x1f00
+ HANDLE_EXCEPTION
+
+ /* Startup routine */
+ .text
+ .global _start
+_start:
+ /* Init stack and frame pointers */
+ l.movhi r1, hi(CONFIG_SYS_INIT_SP_ADDR)
+ l.ori r1, r1, lo(CONFIG_SYS_INIT_SP_ADDR)
+ l.or r2, r0, r1
+
+ /* clear BSS segments */
+ l.movhi r4, hi(_bss_start)
+ l.ori r4, r4, lo(_bss_start)
+ l.movhi r5, hi(_bss_end)
+ l.ori r5, r5, lo(_bss_end)
+.L_clear_bss:
+ l.sw 0(r4), r0
+ l.sfltu r4,r5
+ l.bf .L_clear_bss
+ l.addi r4,r4,4
+
+ /* Reset registers before jumping to board_init */
+ l.andi r3, r0, 0
+ l.andi r4, r0, 0
+ l.andi r5, r0, 0
+ l.andi r6, r0, 0
+ l.andi r7, r0, 0
+ l.andi r8, r0, 0
+ l.andi r9, r0, 0
+ l.andi r10, r0, 0
+ l.andi r11, r0, 0
+ l.andi r12, r0, 0
+ l.andi r13, r0, 0
+ l.andi r14, r0, 0
+ l.andi r15, r0, 0
+ l.andi r17, r0, 0
+ l.andi r18, r0, 0
+ l.andi r19, r0, 0
+ l.andi r20, r0, 0
+ l.andi r21, r0, 0
+ l.andi r22, r0, 0
+ l.andi r23, r0, 0
+ l.andi r24, r0, 0
+ l.andi r25, r0, 0
+ l.andi r26, r0, 0
+ l.andi r27, r0, 0
+ l.andi r28, r0, 0
+ l.andi r29, r0, 0
+ l.andi r30, r0, 0
+ l.andi r31, r0, 0
+
+ l.j board_init
+ l.nop
+
+ .size _start, .-_start
+
+/*
+ * Store state onto stack and call the real exception handler
+ */
+ .section .text
+ .extern exception_handler
+ .type _exception_handler,@function
+
+_exception_handler:
+ /* Store state (r9 already saved)*/
+ l.sw 0x00(r1), r2
+ l.sw 0x04(r1), r3
+ l.sw 0x08(r1), r4
+ l.sw 0x0c(r1), r5
+ l.sw 0x10(r1), r6
+ l.sw 0x14(r1), r7
+ l.sw 0x18(r1), r8
+ l.sw 0x20(r1), r10
+ l.sw 0x24(r1), r11
+ l.sw 0x28(r1), r12
+ l.sw 0x2c(r1), r13
+ l.sw 0x30(r1), r14
+ l.sw 0x34(r1), r15
+ l.sw 0x38(r1), r16
+ l.sw 0x3c(r1), r17
+ l.sw 0x40(r1), r18
+ l.sw 0x44(r1), r19
+ l.sw 0x48(r1), r20
+ l.sw 0x4c(r1), r21
+ l.sw 0x50(r1), r22
+ l.sw 0x54(r1), r23
+ l.sw 0x58(r1), r24
+ l.sw 0x5c(r1), r25
+ l.sw 0x60(r1), r26
+ l.sw 0x64(r1), r27
+ l.sw 0x68(r1), r28
+ l.sw 0x6c(r1), r29
+ l.sw 0x70(r1), r30
+ l.sw 0x74(r1), r31
+
+ /* Save return address */
+ l.or r14, r0, r9
+ /* Call exception handler with the link address as argument */
+ l.jal exception_handler
+ l.or r3, r0, r14
+ /* Load return address */
+ l.or r9, r0, r14
+
+ /* Restore state */
+ l.lwz r2, 0x00(r1)
+ l.lwz r3, 0x04(r1)
+ l.lwz r4, 0x08(r1)
+ l.lwz r5, 0x0c(r1)
+ l.lwz r6, 0x10(r1)
+ l.lwz r7, 0x14(r1)
+ l.lwz r8, 0x18(r1)
+ l.lwz r10, 0x20(r1)
+ l.lwz r11, 0x24(r1)
+ l.lwz r12, 0x28(r1)
+ l.lwz r13, 0x2c(r1)
+ l.lwz r14, 0x30(r1)
+ l.lwz r15, 0x34(r1)
+ l.lwz r16, 0x38(r1)
+ l.lwz r17, 0x3c(r1)
+ l.lwz r18, 0x40(r1)
+ l.lwz r19, 0x44(r1)
+ l.lwz r20, 0x48(r1)
+ l.lwz r21, 0x4c(r1)
+ l.lwz r22, 0x50(r1)
+ l.lwz r23, 0x54(r1)
+ l.lwz r24, 0x58(r1)
+ l.lwz r25, 0x5c(r1)
+ l.lwz r26, 0x60(r1)
+ l.lwz r27, 0x64(r1)
+ l.lwz r28, 0x68(r1)
+ l.lwz r29, 0x6c(r1)
+ l.lwz r30, 0x70(r1)
+ l.lwz r31, 0x74(r1)
+ l.jr r9
+ l.nop