4b9cb9b5b4
git-svn-id: svn://svn.rockbox.org/rockbox/trunk@4935 a1c6a512-1295-4272-9138-f99709370657
187 lines
3.6 KiB
ArmAsm
187 lines
3.6 KiB
ArmAsm
/***************************************************************************
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* __________ __ ___.
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* Open \______ \ ____ ____ | | _\_ |__ _______ ___
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* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
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* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
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* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
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* \/ \/ \/ \/ \/
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* $Id$
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*
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* Copyright (C) 2002 by Linus Nielsen Feltzing
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*
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* All files in this archive are subject to the GNU General Public License.
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* See the file COPYING in the source tree root for full license agreement.
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*
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* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
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* KIND, either express or implied.
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*
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****************************************************************************/
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.section .init.text
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.global start
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start:
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/* We begin with some tricks. If we have built our code to be loaded
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* via the standalone GDB stub, we will have out VBR at some other
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* location than 0x9000000. We must copy the trap vectors for the
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* GDB stub to our vector table.
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* If, on the other hand, we are running standalone we will have
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* the VBR at 0x9000000, and the copy will not do any harm.
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*/
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mov.l vbr_k,r1
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mov.l orig_vbr_k,r2
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/* Move the invalid instruction vector (4) */
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mov #4,r0
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shll2 r0
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mov.l @(r0,r2),r3
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mov.l r3,@(r0,r1)
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/* Move the invalid slot vector (6) */
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mov #6,r0
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shll2 r0
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mov.l @(r0,r2),r3
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mov.l r3,@(r0,r1)
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/* Move the bus error vector (9) */
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mov #9,r0
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shll2 r0
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mov.l @(r0,r2),r3
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mov.l r3,@(r0,r1)
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/* Move the DMA bus error vector (10) */
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mov #10,r0
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shll2 r0
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mov.l @(r0,r2),r3
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mov.l r3,@(r0,r1)
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/* Move the NMI vector as well (11) */
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mov #11,r0
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shll2 r0
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mov.l @(r0,r2),r3
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mov.l r3,@(r0,r1)
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/* Move the breakpoint trap vector (32) */
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mov #32,r0
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shll2 r0
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mov.l @(r0,r2),r3
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mov.l r3,@(r0,r1)
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/* Move the IO trap vector (33) */
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mov #33,r0
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shll2 r0
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mov.l @(r0,r2),r3
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mov.l r3,@(r0,r1)
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/* Move the serial Rx interrupt vector (105) */
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mov #105,r0
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shll2 r0
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mov.l @(r0,r2),r3
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mov.l r3,@(r0,r1)
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/* Move the single step trap vector (127) */
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mov #127,r0
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shll2 r0
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mov.l @(r0,r2),r3
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mov.l r3,@(r0,r1)
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ldc r1,vbr
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/* Now let's get on with the normal business */
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mov.l stack_k,r15
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/* zero out bss */
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mov.l edata_k,r0
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mov.l end_k,r1
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mov #0,r2
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start_l:
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mov.l r2,@r0
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add #4,r0
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cmp/ge r1,r0
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bf start_l
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nop
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/* copy the .iram section */
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mov.l iramcopy_k,r0
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mov.l iram_k,r1
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mov.l iramend_k,r2
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copy_l:
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mov.l @r0,r3
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mov.l r3,@r1
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add #4,r0
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add #4,r1
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cmp/ge r2,r1
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bf copy_l
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nop
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/* copy the .data section, for rombased execution */
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mov.l datacopy_k,r0
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mov.l data_k,r1
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mov.l dataend_k,r2
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/* Don't copy if src and dest are equal */
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cmp/eq r0,r1
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bt nodatacopy
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copy_l2:
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mov.l @r0,r3
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mov.l r3,@r1
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add #4,r0
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add #4,r1
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cmp/ge r2,r1
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bf copy_l2
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nop
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nodatacopy:
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/* Munge the main thread stack */
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mov.l stack_k,r2
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mov.l deadbeef_k,r0
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mov.l stackbegin_k,r1
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munge_loop:
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mov.l r0,@r1
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add #4,r1
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cmp/ge r2,r1
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bf munge_loop
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nop
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mov #0,r0
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ldc r0,gbr
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! call the mainline
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mov.l main_k,r0
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jsr @r0
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nop
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.hoo:
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bra .hoo
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.align 2
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stack_k:
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.long _stackend
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stackbegin_k:
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.long _stackbegin
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deadbeef_k:
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.long 0xdeadbeef
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edata_k:
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.long _edata
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end_k:
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.long _end
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iramcopy_k:
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.long _iramcopy
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iram_k:
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.long _iramstart
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iramend_k:
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.long _iramend
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datacopy_k:
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.long _datacopy
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data_k:
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.long _datastart
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dataend_k:
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.long _dataend
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main_k:
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.long _main
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vbr_k:
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.long vectors
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orig_vbr_k:
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.long 0x9000000
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.section .resetvectors
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vectors:
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.long start
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.long _stackend
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.long start
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.long _stackend
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