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https://github.com/autc04/Retro68.git
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145 lines
2.8 KiB
ArmAsm
145 lines
2.8 KiB
ArmAsm
/*
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* C startup code for the Fujitsu SPARClite demo board
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*
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* Copyright (c) 1995, 1996 Cygnus Support
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*
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* The authors hereby grant permission to use, copy, modify, distribute,
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* and license this software and its documentation for any purpose, provided
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* that existing copyright notices are retained in all copies and that this
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* notice is included verbatim in any distributions. No written agreement,
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* license, or royalty fee is required for any of the authorized uses.
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* Modifications to this software may be copyrighted by their authors
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* and need not follow the licensing terms described here, provided that
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* the new terms are clearly indicated on the first page of each file where
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* they apply.
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*/
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#include "asm.h"
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#ifdef TARGET_CPU_SPARC64
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#define STACK_BIAS 2047
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#define SAVE_SIZE -128
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#else
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#define SAVE_SIZE -64
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#endif
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.data
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.align 8
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SYM(environ): ! this is the first address in the data section
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.long 0
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SYM(argc):
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.long 0
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.text
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.align 8
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.globl SYM(start)
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.globl start
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SYM(start):
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start:
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/* see if the stack is already setup. if not, then default
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* to using the value of %sp as set by the ROM monitor
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*/
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sethi %hi(__stack), %g1
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or %g1,%lo(__stack),%g1
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cmp %g0,%g1
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be 1f
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nop
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#ifdef STACK_BIAS
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sub %g1, STACK_BIAS, %g1
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#endif
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mov %g1, %sp ! set the stack pointer
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mov 0, %fp
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1:
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/* zero the bss section */
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sethi %hi(__bss_start),%g2
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or %g2,%lo(__bss_start),%g2 ! start of bss
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sethi %hi(_end),%g3
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or %g3,%lo(_end),%g3 ! end of bss
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mov %g0,%g1 ! so std has two zeros
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zerobss:
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std %g0,[%g2]
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add %g2,8,%g2
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cmp %g2,%g3
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bleu,a zerobss
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nop
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/*
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* initialize target specific stuff. Only execute these
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* functions it they exist.
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*/
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init:
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sethi %hi(SYM(hardware_init_hook)), %g1
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or %g1,%lo(SYM(hardware_init_hook)),%g1
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cmp %g0,%g1
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be 1f
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nop
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call SYM(hardware_init_hook)
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nop
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1:
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sethi %hi(SYM(software_init_hook)), %g1
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or %g1,%lo(SYM(software_init_hook)),%g1
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cmp %g0,%g1
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be 2f
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nop
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call SYM(software_init_hook)
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nop
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2:
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set SYM(__sigtramp), %o0
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call SYM(__install_signal_handler)
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nop
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set do_dtors,%o0
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call SYM(atexit)
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nop
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call do_ctors
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nop
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set SYM(argc), %o0
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call SYM(__getProgramArgs)
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nop
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mov %o0, %o1
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set SYM(argc), %o0
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ld [%o0], %o0
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call SYM(main)
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nop
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/* call exit from the C library so atexit gets called, and the
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* C++ destructors get run. This calls our exit routine below
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* when it's done.
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*/
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call SYM(exit)
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nop
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do_ctors:
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save %sp,SAVE_SIZE,%sp
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set __CTOR_LIST__,%l0
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our_entry:
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ld [%l0],%l1
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add %l0,4,%l0
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tst %l1
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1:
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beq 2f
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nop
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ld [%l0],%l2
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add %l0,4,%l0
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call %l2
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nop
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deccc %l1
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b 1b
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nop
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2:
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ret
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restore
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do_dtors:
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save %sp,SAVE_SIZE,%sp
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set __DTOR_LIST__,%l0
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b our_entry
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nop
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