/* * 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 #include #include /* * 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 * ************************************************************************* */ .globl _TEXT_BASE _TEXT_BASE: .word CONFIG_SYS_TEXT_BASE /* * 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 /* IRQ stack memory (calculated at run-time) + 8 bytes */ .globl IRQ_STACK_START_IN IRQ_STACK_START_IN: .word 0x0badc0de .globl _datarel_start _datarel_start: .word __datarel_start .globl _datarelrolocal_start _datarelrolocal_start: .word __datarelrolocal_start .globl _datarellocal_start _datarellocal_start: .word __datarellocal_start .globl _datarelro_start _datarelro_start: .word __datarelro_start .globl _got_start _got_start: .word __got_start .globl _got_end _got_end: .word __got_end /* * the actual reset code */ reset: /* * set the cpu to SVC32 mode */ mrs r0,cpsr bic r0,r0,#0x1f orr r0,r0,#0xd3 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 /* Set stackpointer in internal RAM to call board_init_f */ call_board_init_f: ldr sp, =(CONFIG_SYS_INIT_SP_ADDR) ldr r0,=0x00000000 bl board_init_f /*------------------------------------------------------------------------------*/ /* * void relocate_code (addr_sp, gd, addr_moni) * * This "function" does not return, instead it continues in RAM * after relocating the monitor code. * */ .globl relocate_code relocate_code: mov r4, r0 /* save addr_sp */ mov r5, r1 /* save addr of gd */ mov r6, r2 /* save addr of destination */ mov r7, r2 /* save addr of destination */ /* Set up the stack */ stack_setup: mov sp, r4 adr r0, _start ldr r2, _TEXT_BASE ldr r3, _bss_start sub r2, r3, r2 /* r2 <- size of armboot */ add r2, r0, r2 /* r2 <- source end address */ cmp r0, r6 beq clear_bss copy_loop: ldmia r0!, {r9-r10} /* copy from source address [r0] */ stmia r6!, {r9-r10} /* copy to target address [r1] */ cmp r0, r2 /* until source end address [r2] */ blo copy_loop #ifndef CONFIG_PRELOADER /* fix got entries */ ldr r1, _TEXT_BASE /* Text base */ mov r0, r7 /* reloc addr */ ldr r2, _got_start /* addr in Flash */ ldr r3, _got_end /* addr in Flash */ sub r3, r3, r1 add r3, r3, r0 sub r2, r2, r1 add r2, r2, r0 fixloop: ldr r4, [r2] sub r4, r4, r1 add r4, r4, r0 str r4, [r2] add r2, r2, #4 cmp r2, r3 blo fixloop #endif /* 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 blo vector_copy_loop clear_bss: #ifndef CONFIG_PRELOADER ldr r0, _bss_start ldr r1, _bss_end ldr r3, _TEXT_BASE /* Text base */ mov r4, r7 /* reloc addr */ sub r0, r0, r3 add r0, r0, r4 sub r1, r1, r3 add r1, r1, r4 mov r2, #0x00000000 /* clear */ clbss_l:str r2, [r0] /* clear loop... */ add r0, r0, #4 cmp r0, r1 bne clbss_l bl coloured_LED_init bl red_LED_on #endif /* * We are done. Do not return, instead branch to second part of board * initialization, now running from RAM. */ ldr r0, _TEXT_BASE ldr r2, _board_init_r sub r2, r2, r0 add r2, r2, r7 /* position from board_init_r in RAM */ /* setup parameters for board_init_r */ mov r0, r5 /* gd_t */ mov r1, r7 /* dest_addr */ /* jump to it ... */ mov lr, r2 mov pc, lr _board_init_r: .word board_init_r /* ************************************************************************* * * 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