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+/*
+ * Startup Code for S3C44B0 CPU-core
+ *
+ * (C) Copyright 2004
+ * DAVE Srl
+ *
+ * http://www.dave-tech.it
+ * http://www.wawnet.biz
+ * mailto:info@wawnet.biz
+ *
+ * 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>
+#include <version.h>
+
+
+/*
+ * Jump vector table
+ */
+
+
+.globl _start
+_start: b reset
+ add pc, pc, #0x0c000000
+ add pc, pc, #0x0c000000
+ add pc, pc, #0x0c000000
+ add pc, pc, #0x0c000000
+ add pc, pc, #0x0c000000
+ add pc, pc, #0x0c000000
+ add pc, pc, #0x0c000000
+
+ .balignl 16,0xdeadbeef
+
+
+/*
+ *************************************************************************
+ *
+ * Startup Code (reset vector)
+ *
+ * do important init only if we don't start from memory!
+ * relocate u-boot to ram
+ * setup stack
+ * jump to second stage
+ *
+ *************************************************************************
+ */
+
+_TEXT_BASE:
+ .word TEXT_BASE
+
+.globl _armboot_start
+_armboot_start:
+ .word _start
+
+/*
+ * These are defined in the board-specific linker script.
+ */
+.globl _bss_start
+_bss_start:
+ .word __bss_start
+
+.globl _bss_end
+_bss_end:
+ .word _end
+
+#ifdef CONFIG_USE_IRQ
+/* IRQ stack memory (calculated at run-time) */
+.globl IRQ_STACK_START
+IRQ_STACK_START:
+ .word 0x0badc0de
+
+/* IRQ stack memory (calculated at run-time) */
+.globl FIQ_STACK_START
+FIQ_STACK_START:
+ .word 0x0badc0de
+#endif
+
+
+/*
+ * the actual reset code
+ */
+
+reset:
+ /*
+ * set the cpu to SVC32 mode
+ */
+ mrs r0,cpsr
+ bic r0,r0,#0x1f
+ orr r0,r0,#0x13
+ msr cpsr,r0
+
+ /*
+ * we do sys-critical inits only at reboot,
+ * not when booting from ram!
+ */
+
+#ifndef CONFIG_SKIP_LOWLEVEL_INIT
+ bl cpu_init_crit
+ /*
+ * before relocating, we have to setup RAM timing
+ * because memory timing is board-dependend, you will
+ * find a lowlevel_init.S in your board directory.
+ */
+ bl lowlevel_init
+#endif
+
+#ifndef CONFIG_SKIP_RELOCATE_UBOOT
+relocate: /* relocate U-Boot to RAM */
+ adr r0, _start /* r0 <- current position of code */
+ ldr r1, _TEXT_BASE /* test if we run from flash or RAM */
+ cmp r0, r1 /* don't reloc during debug */
+ beq stack_setup
+
+ ldr r2, _armboot_start
+ ldr r3, _bss_start
+ sub r2, r3, r2 /* r2 <- size of armboot */
+ add r2, r0, r2 /* r2 <- source end address */
+
+copy_loop:
+ ldmia r0!, {r3-r10} /* copy from source address [r0] */
+ stmia r1!, {r3-r10} /* copy to target address [r1] */
+ cmp r0, r2 /* until source end addreee [r2] */
+ ble copy_loop
+
+/*
+ now copy to sram the interrupt vector
+*/
+ adr r0, real_vectors
+ add r2, r0, #1024
+ ldr r1, =0x0c000000
+ add r1, r1, #0x08
+vector_copy_loop:
+ ldmia r0!, {r3-r10}
+ stmia r1!, {r3-r10}
+ cmp r0, r2
+ ble vector_copy_loop
+#endif /* CONFIG_SKIP_RELOCATE_UBOOT */
+
+ /* Set up the stack */
+stack_setup:
+ ldr r0, _TEXT_BASE /* upper 128 KiB: relocated uboot */
+ sub r0, r0, #CONFIG_SYS_MALLOC_LEN /* malloc area */
+ sub r0, r0, #CONFIG_SYS_GBL_DATA_SIZE /* bdinfo */
+#ifdef CONFIG_USE_IRQ
+ sub r0, r0, #(CONFIG_STACKSIZE_IRQ+CONFIG_STACKSIZE_FIQ)
+#endif
+ sub sp, r0, #12 /* leave 3 words for abort-stack */
+
+ ldr pc, _start_armboot
+
+_start_armboot: .word start_armboot
+
+
+/*
+ *************************************************************************
+ *
+ * CPU_init_critical registers
+ *
+ * setup important registers
+ * setup memory timing
+ *
+ *************************************************************************
+ */
+
+#define INTCON (0x01c00000+0x200000)
+#define INTMSK (0x01c00000+0x20000c)
+#define LOCKTIME (0x01c00000+0x18000c)
+#define PLLCON (0x01c00000+0x180000)
+#define CLKCON (0x01c00000+0x180004)
+#define WTCON (0x01c00000+0x130000)
+cpu_init_crit:
+ /* disable watch dog */
+ ldr r0, =WTCON
+ ldr r1, =0x0
+ str r1, [r0]
+
+ /*
+ * mask all IRQs by clearing all bits in the INTMRs
+ */
+ ldr r1,=INTMSK
+ ldr r0, =0x03fffeff
+ str r0, [r1]
+
+ ldr r1, =INTCON
+ ldr r0, =0x05
+ str r0, [r1]
+
+ /* Set Clock Control Register */
+ ldr r1, =LOCKTIME
+ ldrb r0, =800
+ strb r0, [r1]
+
+ ldr r1, =PLLCON
+
+#if CONFIG_S3C44B0_CLOCK_SPEED==66
+ ldr r0, =0x34031 /* 66MHz (Quartz=11MHz) */
+#elif CONFIG_S3C44B0_CLOCK_SPEED==75
+ ldr r0, =0x610c1 /*B2: Xtal=20mhz Fclk=75MHz */
+#else
+# error CONFIG_S3C44B0_CLOCK_SPEED undefined
+#endif
+
+ str r0, [r1]
+
+ ldr r1,=CLKCON
+ ldr r0, =0x7ff8
+ str r0, [r1]
+
+ mov pc, lr
+
+
+/*************************************************/
+/* interrupt vectors */
+/*************************************************/
+real_vectors:
+ b reset
+ b undefined_instruction
+ b software_interrupt
+ b prefetch_abort
+ b data_abort
+ b not_used
+ b irq
+ b fiq
+
+/*************************************************/
+
+undefined_instruction:
+ mov r6, #3
+ b reset
+
+software_interrupt:
+ mov r6, #4
+ b reset
+
+prefetch_abort:
+ mov r6, #5
+ b reset
+
+data_abort:
+ mov r6, #6
+ b reset
+
+not_used:
+ /* we *should* never reach this */
+ mov r6, #7
+ b reset
+
+irq:
+ mov r6, #8
+ b reset
+
+fiq:
+ mov r6, #9
+ b reset