/*************************************************************************** * __________ __ ___. * Open \______ \ ____ ____ | | _\_ |__ _______ ___ * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ * \/ \/ \/ \/ \/ * * Copyright (C) 2002 by Linus Nielsen Feltzing * Copyright (C) 2010 by Michael Sevakis * * 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 software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY * KIND, either express or implied. * ****************************************************************************/ #include "config.h" #include "cpu.h" /* PortalPlayer bootloader and startup code based on startup.s from the iPodLinux * loader * * Copyright (c) 2003, Daniel Palffy (dpalffy (at) rainstorm.org) * Copyright (c) 2005, Bernard Leach * */ .equ PROC_ID, 0x60000000 .equ CPU_IDIS, 0x60004028 .equ CPU_CTRL, 0x60007000 .equ CPU_STATUS, 0x60007000 .equ COP_IDIS, 0x60004038 .equ COP_CTRL, 0x60007004 .equ COP_STATUS, 0x60007004 .equ CPU_SLEEPING,0x80000000 .equ COP_SLEEPING,0x80000000 .equ SLEEP, 0x80000000 .equ WAKE, 0x00000000 .equ MMAP_LOG, 0xf000f000 /* MMAP0 */ .equ MMAP_PHYS, 0xf000f004 .equ INT_VECT_TBL,0x6000f100 .equ CACHE_CTRL, 0x6000c000 .equ CACHE_ENAB, 0x1 .equ CACHE_OP_COMMIT_DISCARD, 0x1 .equ CACHE_OP_COMMIT , 0x0 #if MEMORYSIZE > 32 .equ MMAP_MASK, 0x00003c00 #else .equ MMAP_MASK, 0x00003e00 #endif .equ MMAP_FLAGS, 0x00000f84 /* * Entry point */ .section .init.text,"ax",%progbits .global start start: b newstart #ifdef IPOD_ARCH .align 8 /* starts at 0x100 */ .global boot_table boot_table: /* here comes the boot table, don't move its offset - preceding code+data must stay <= 256 bytes */ .space 400 #else /* !IPOD_ARCH */ /* (more than enough) space for exception vectors and mi4 magic */ .space 68*4 #endif /* IPOD_ARCH */ newstart: msr cpsr_c, #0xd3 /* enter supervisor mode, disable IRQ/FIQ */ adr r4, start /* cache initial load address */ /* Copy startup stub to IRAM since we need to both move the bootloader's * location, which could overlap itself, and setup the memory mapper. */ adr r0, start_stub_begin mov r1, #0x40000000 adr r2, start_stub_end 1: ldr r3, [r0], #4 str r3, [r1], #4 cmp r0, r2 blo 1b mov pc, #0x40000000 start_stub_begin: ldr r0, =PROC_ID ldrb r0, [r0] cmp r0, #0x55 beq cpu cop: mov r0, #CACHE_OP_COMMIT_DISCARD bl cache_operation ldr r1, =COP_CTRL mov r0, #SLEEP /* sleep us (co-processor) while bootloader is copied */ str r0, [r1] nop nop nop /* branch to final physical load address */ ldr r2, =1f and r4, r4, #0xfc000000 add pc, r2, r4 1: /* wait for bootloader to finish */ str r0, [r1] nop nop nop /* branch to the address returned by main() */ adr r0, startup_loc ldr pc, [r0] cpu: /* wait for COP to sleep */ ldr r1, =COP_STATUS 1: ldr r0, [r1] tst r0, #COP_SLEEPING beq 1b mov r0, #CACHE_OP_COMMIT_DISCARD bl cache_operation /* move bootloader to the correct load address if needed */ ldr r1, =_loadaddress cmp r4, r1 ldrne r2, =_loadaddressend movne r0, r4 sublo r3, r2, r1 /* size */ addlo r0, r0, r3 /* initial load end addr */ 1: /* lower to higher move - copy up */ cmphi r2, r1 ldrhi r3, [r0], #4 strhi r3, [r1], #4 bhi 1b 1: /* higher to lower move - copy down */ cmplo r1, r2 ldrlo r3, [r0, #-4]! strlo r3, [r2, #-4]! blo 1b mov r0, #CACHE_OP_COMMIT bl cache_operation and r4, r4, #0xfc000000 ldr r0, =MMAP_FLAGS orr r0, r0, r4 /* adjust for execute address */ ldr r1, =MMAP_MASK ldr r2, =MMAP_LOG ldr r3, =MMAP_PHYS str r1, [r2] /* MMAP_LOG = MMAP_MASK */ str r0, [r3] /* MMAP_PHYS = MMAP_FLAGS | SDRAM base addr */ /* wake the COP to jump it to the correct place */ ldr r1, =COP_CTRL mov r0, #WAKE str r0, [r1] /* wait for COP to halt then loading may proceed */ ldr r1, =COP_STATUS 1: ldr r0, [r1] tst r0, #COP_SLEEPING beq 1b ldr r0, =start_stub_end add pc, r0, r4 cache_operation: /* (bool commit_discard) */ ldr r2, =CACHE_CTRL ldr r1, [r2] tst r1, #CACHE_ENAB bxeq lr cmp r0, #CACHE_OP_COMMIT ldr r0, =0xf000f044 ldr r1, [r0] orrne r1, r1, #0x6 orreq r1, r1, #0x2 str r1, [r0] 1: ldr r1, [r2] tst r1, #0x8000 bne 1b bx lr .ltorg /* constants used in stub come with us to IRAM */ start_stub_end: /* now executing from final physical address */ /* copy the vector addresses to the table */ ldr r0, =INT_VECT_TBL adr r1, vectorsstart adr r2, vectorsend 1: cmp r2, r1 ldrhi r3, [r1], #4 strhi r3, [r0], #4 bhi 1b /* Copy the IRAM */ ldr r0, =_iramcopy ldr r1, =_iramstart ldr r2, =_iramend 1: cmp r2, r1 ldrhi r3, [r0], #4 strhi r3, [r1], #4 bhi 1b mov r0, #0 /* Zero out IBSS */ ldr r1, =_iedata ldr r2, =_iend 1: cmp r2, r1 strhi r0, [r1], #4 bhi 1b /* Initialise bss/ncbss sections to zero */ ldr r1, =_edata ldr r2, =_end 1: cmp r2, r1 strhi r0, [r1], #4 bhi 1b /* Set up stack for IRQ mode */ msr cpsr_c, #0xd2 /* IRQ/FIQ disabled */ ldr sp, =irq_stack /* Let svc, abort and undefined modes use irq stack */ msr cpsr_c, #0xd3 ldr sp, =irq_stack msr cpsr_c, #0xd7 /* IRQ/FIQ disabled */ ldr sp, =irq_stack msr cpsr_c, #0xdb /* IRQ/FIQ disabled */ ldr sp, =irq_stack /* Switch back to sys mode */ msr cpsr_c, #0xdf /* Set up some stack and munge it with 0xdeadbeef */ ldr r0, =0xdeadbeef ldr r1, =stackbegin ldr sp, =stackend 1: cmp sp, r1 strhi r0, [r1], #4 bhi 1b /* execute the loader - this will load an image to 0x10000000 */ ldr r0, =main mov lr, pc bx r0 /* store actual startup location returned by main() */ ldr r1, =startup_loc str r0, [r1] /* write back anything loaded + startup_loc */ mov r0, #CACHE_OP_COMMIT bl cache_operation mov r0, #0 /* disable memory mapper */ ldr r1, =MMAP_LOG ldr r2, =MMAP_PHYS str r0, [r1] str r0, [r2] /* bring COP back to life */ ldr r1, =COP_CTRL mov r0, #WAKE str r0, [r1] /* after this point, r0-r3 are reserved for OF magic */ #if defined(SANSA_C200) || defined(PHILIPS_HDD1630) /* Magic for loading the c200 OF */ ldr r0, =0xb00d10ad mov r1, #0x700 ldr r2, =0xfff0 mov r3, #0x7 #endif #if defined(PHILIPS_HDD6330) /* Magic for loading the HDD6XX0 OF */ ldr r0, =0xb00d10ad mov r1, #0x800 ldr r2, =0xfff0 mov r3, #0x7 #endif /* branch to the address returned by main() */ adr r4, startup_loc ldr pc, [r4] startup_loc: .word 0x00000000 /* exception handlers: will be copied to local vector table */ vectorsstart: .word newstart .word undef_instr_handler .word software_int_handler .word prefetch_abort_handler .word data_abort_handler .word reserved_handler .word irq_handler .word fiq_handler vectorsend: .text /* All illegal exceptions call into UIE with exception address as first parameter. This is calculated differently depending on which exception we're in. Second parameter is exception number, used for a string lookup in UIE. */ undef_instr_handler: sub r0, lr, #4 mov r1, #0 b UIE /* We run sys mode most of the time, and should never see a software exception being thrown. Make it illegal and call UIE. */ software_int_handler: reserved_handler: sub r0, lr, #4 mov r1, #4 b UIE prefetch_abort_handler: sub r0, lr, #4 mov r1, #1 b UIE /* should never happen in the bootloader */ fiq_handler: subs pc, lr, #4 /* 256 words of IRQ stack */ .section .bss .balign 16 .space 256*4 irq_stack: