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+/*
+ * (C) Copyright 2007 Michal Simek
+ * (C) Copyright 2004 Atmark Techno, Inc.
+ *
+ * Michal SIMEK <monstr@monstr.eu>
+ * Yasushi SHOJI <yashi@atmark-techno.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
+ */
+
+#include <config.h>
+
+ .text
+ .global _start
+_start:
+ mts rmsr, r0 /* disable cache */
+ addi r1, r0, CONFIG_SYS_INIT_SP_OFFSET
+ addi r1, r1, -4 /* Decrement SP to top of memory */
+ /* add opcode instruction for 32bit jump - 2 instruction imm & brai*/
+ addi r6, r0, 0xb0000000 /* hex b000 opcode imm */
+ swi r6, r0, 0x0 /* reset address */
+ swi r6, r0, 0x8 /* user vector exception */
+ swi r6, r0, 0x10 /* interrupt */
+ swi r6, r0, 0x20 /* hardware exception */
+
+ addi r6, r0, 0xb8080000 /* hew b808 opcode brai*/
+ swi r6, r0, 0x4 /* reset address */
+ swi r6, r0, 0xC /* user vector exception */
+ swi r6, r0, 0x14 /* interrupt */
+ swi r6, r0, 0x24 /* hardware exception */
+
+#ifdef CONFIG_SYS_RESET_ADDRESS
+ /* reset address */
+ addik r6, r0, CONFIG_SYS_RESET_ADDRESS
+ sw r6, r1, r0
+ lhu r7, r1, r0
+ shi r7, r0, 0x2
+ shi r6, r0, 0x6
+/*
+ * Copy U-Boot code to TEXT_BASE
+ * solve problem with sbrk_base
+ */
+#if (CONFIG_SYS_RESET_ADDRESS != TEXT_BASE)
+ addi r4, r0, __end
+ addi r5, r0, __text_start
+ rsub r4, r5, r4 /* size = __end - __text_start */
+ addi r6, r0, CONFIG_SYS_RESET_ADDRESS /* source address */
+ addi r7, r0, 0 /* counter */
+4:
+ lw r8, r6, r7
+ sw r8, r5, r7
+ addi r7, r7, 0x4
+ cmp r8, r4, r7
+ blti r8, 4b
+#endif
+#endif
+
+#ifdef CONFIG_SYS_USR_EXCEP
+ /* user_vector_exception */
+ addik r6, r0, _exception_handler
+ sw r6, r1, r0
+ lhu r7, r1, r0
+ shi r7, r0, 0xa
+ shi r6, r0, 0xe
+#endif
+
+#ifdef CONFIG_SYS_INTC_0
+ /* interrupt_handler */
+ addik r6, r0, _interrupt_handler
+ sw r6, r1, r0
+ lhu r7, r1, r0
+ shi r7, r0, 0x12
+ shi r6, r0, 0x16
+#endif
+
+ /* hardware exception */
+ addik r6, r0, _hw_exception_handler
+ sw r6, r1, r0
+ lhu r7, r1, r0
+ shi r7, r0, 0x22
+ shi r6, r0, 0x26
+
+ /* enable instruction and data cache */
+ mfs r12, rmsr
+ ori r12, r12, 0xa0
+ mts rmsr, r12
+
+clear_bss:
+ /* clear BSS segments */
+ addi r5, r0, __bss_start
+ addi r4, r0, __bss_end
+ cmp r6, r5, r4
+ beqi r6, 3f
+2:
+ swi r0, r5, 0 /* write zero to loc */
+ addi r5, r5, 4 /* increment to next loc */
+ cmp r6, r5, r4 /* check if we have reach the end */
+ bnei r6, 2b
+3: /* jumping to board_init */
+ brai board_init
+1: bri 1b
+
+/*
+ * Read 16bit little endian
+ */
+ .text
+ .global in16
+ .ent in16
+ .align 2
+in16: lhu r3, r0, r5
+ bslli r4, r3, 8
+ bsrli r3, r3, 8
+ andi r4, r4, 0xffff
+ or r3, r3, r4
+ rtsd r15, 8
+ sext16 r3, r3
+ .end in16
+
+/*
+ * Write 16bit little endian
+ * first parameter(r5) - address, second(r6) - short value
+ */
+ .text
+ .global out16
+ .ent out16
+ .align 2
+out16: bslli r3, r6, 8
+ bsrli r6, r6, 8
+ andi r3, r3, 0xffff
+ or r3, r3, r6
+ sh r3, r0, r5
+ rtsd r15, 8
+ or r0, r0, r0
+ .end out16