| /*************************************************************************** |
| * __________ __ ___. |
| * Open \______ \ ____ ____ | | _\_ |__ _______ ___ |
| * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / |
| * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < |
| * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ |
| * \/ \/ \/ \/ \/ |
| * $Id$ |
| * |
| * Copyright (C) 2008 Rafaël Carré |
| * |
| * 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. |
| * |
| ****************************************************************************/ |
| |
| .text |
| |
| /* This is the size of the Clip's RAM, but there is nothing to be gained |
| (at the moment) by making use of the larger RAM of other targets */ |
| |
| .set DRAM_SIZE, 0x50000 |
| |
| .set GPIOA, 0xC80B0000 |
| .set GPIOB, 0xC80C0000 |
| .set GPIOC, 0xC80D0000 |
| .set GPIOD, 0xC80E0000 |
| .set CGU_PERI, 0xC80F0014 |
| |
| |
| /* Vectors */ |
| ldr pc, =start |
| .word 0 |
| .word 0 |
| .word 0 |
| .word 0 |
| .word 0 |
| .word 0 |
| .word 0 |
| |
| /* These values are filled in by mkamsboot - don't move them from offset 0x20 */ |
| uclunpack_end: .word 0 /* End of the ucl_unpack function */ |
| uclunpack_size: .word 0 /* Size in bytes of the ucl_unpack function */ |
| |
| ucl_of_end: .word 0 /* End of the ucl-compressed OF image */ |
| ucl_of_size: .word 0 /* Size in bytes of the compressed OF image */ |
| |
| ucl_rb_end: .word 0 /* End of the ucl-compressed RB image */ |
| ucl_rb_size: .word 0 /* Size in bytes of the compressed RB image */ |
| |
| |
| start: |
| /* First copy the UCL unpack function to the end of RAM */ |
| ldr r0, uclunpack_end /* Source */ |
| ldr r1, uclunpack_size /* Source length */ |
| sub r2, r0, r1 /* Source start - 1*/ |
| |
| ldr r3, =(DRAM_SIZE-1) /* Destination end */ |
| |
| uclcopy: |
| ldrb r4, [r0], #-1 |
| strb r4, [r3], #-1 |
| cmp r2, r0 |
| bne uclcopy |
| |
| add r5, r3, #2 /* r5 is entry point of copy of uclunpack */ |
| /* function, plus one (for thumb mode */ |
| |
| /* enable gpio clock */ |
| ldr r0, =CGU_PERI |
| ldr r1, [r0] |
| orr r1, r1, #(1<<16) |
| str r1, [r0] |
| |
| |
| #ifndef SANSA_M200V4 /* this doesnt work for m200 */ |
| /* we check A3 unconditionally of the model because it seems to be */ |
| /* either hold, either usb on every model */ |
| /* TODO: make it USB on all AMS Sansas for consistency, USB is safer too */ |
| |
| ldr r0, =GPIOA |
| mov r1, #0 |
| str r1, [r0, #0x400] |
| #ifdef SANSA_C200V2 |
| ldr r1, [r0, #0x8] /* USB is A1 on C200 */ |
| #elif defined(SANSA_CLIP) |
| ldr r1, [r0, #0x100] /* USB is A6 on Clip */ |
| #else |
| ldr r1, [r0, #0x20] /* read pin A3 */ |
| #endif |
| cmp r1, #0 |
| bne boot_of |
| #endif |
| |
| /* here are model specific tests, for dual boot without a computer */ |
| |
| #ifdef SANSA_CLIP |
| /* HOME button */ |
| .set row, (1<<6) /* enable output on C6 */ |
| ldr r0, =GPIOC |
| mov r1, #row |
| str r1, [r0, #0x400] |
| str r1, [r0, #(4*row)] |
| |
| .set col, (1<<2) /* read keyscan column B2 */ |
| ldr r0, =GPIOB |
| mov r1, #0 |
| str r1, [r0, #0x400] |
| ldr r1, [r0, #(4*col)] |
| |
| cmp r1, #0 |
| bne boot_of |
| #elif defined(SANSA_E200V2) || defined(SANSA_FUZE) |
| /* LEFT button */ |
| ldr r0, =GPIOC |
| mov r1, #0 |
| str r1, [r0, #0x400] |
| ldr r1, [r0, #0x20] /* read pin C3 */ |
| |
| cmp r1, #0 /* C3 = #0 means button pressed */ |
| beq boot_of |
| #elif defined(SANSA_C200V2) |
| /* check for RIGHT on C6, should maybe changed to LEFT as soon as it |
| * known in which pin that is in order for consistency */ |
| ldr r0, =GPIOC |
| mov r1, #0 |
| str r1, [r0, #0x400] /* set pin to output */ |
| |
| ldr r1, [r0, #256] /* 1<<(6+2) */ |
| cmp r1, #0 /* C6 low means button pressed */ |
| beq boot_of |
| #elif defined(SANSA_M200V4) |
| /* LEFT button */ |
| .set row, (1<<5) /* enable output on A5 */ |
| ldr r0, =GPIOA |
| mov r1, #row |
| str r1, [r0, #0x400] |
| str r1, [r0, #(4*row)] |
| |
| .set col, (1<<0) /* read keyscan column A0 */ |
| ldr r2, [r0, #(4*col)] |
| |
| /* check value read (1 means button pressed) */ |
| cmp r2, #0 |
| bne boot_of |
| #else |
| #error No target-specific key check defined! |
| #endif |
| |
| /* No button was held, so we boot rockbox */ |
| ldr r0, ucl_rb_end /* Address of compressed image */ |
| ldr r1, ucl_rb_size /* Compressed size */ |
| b decompress |
| |
| boot_of: |
| ldr r0, ucl_of_end /* Address of compressed image */ |
| ldr r1, ucl_of_size /* Compressed size */ |
| |
| |
| decompress: |
| /* At this point: */ |
| /* r5 = entry point (plus one for thumb) of uclunpack function */ |
| /* r3 = destination_end for copy of UCL image */ |
| /* r0 = source_end for UCL image to copy */ |
| /* r1 = size of UCL image to copy */ |
| |
| sub r4, r3, r1 /* r4 := destination_start - 1 */ |
| |
| fw_copy: |
| ldrb r2, [r0], #-1 |
| strb r2, [r3], #-1 |
| cmp r3, r4 /* Stop when we reached dest_start-1 */ |
| bne fw_copy |
| |
| /* Call the ucl decompress function, which will branch to 0x0 */ |
| /* on completion */ |
| add r0, r3, #1 /* r0 := Start of compressed image */ |
| /* r1 already contains compressed size */ |
| mov r2, #0 /* r2 := Destination for unpacking */ |
| bx r5 /* Branch to uclunpack, switching to thumb */ |
| |
| /* never reached */ |