source: mainline/uspace/lib/c/arch/arm32/src/entry.S@ b51ee38

#
# Copyright (c) 2007 Michal Kebrt, Pavel Jancik
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
#
# - Redistributions of source code must retain the above copyright
#   notice, this list of conditions and the following disclaimer.
# - Redistributions in binary form must reproduce the above copyright
#   notice, this list of conditions and the following disclaimer in the
#   documentation and/or other materials provided with the distribution.
# - The name of the author may not be used to endorse or promote products
#   derived from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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#

#include <abi/asmtool.h>

.text

.org 0

## User-space task entry point
#
# r1 contains the PCB pointer
# r2 contains the RAS page address
#
SYMBOL(_start)
        # Store the RAS page address into the ras_page variable
        ldr r0, =ras_page
        str r2, [r0]

        #
        # Create the first stack frame.
        #
        mov fp, #0
        mov ip, sp
        push {fp, ip, lr, pc}
        sub fp, ip, #4

        # Pass pcb_ptr to __c_start as the first argument (in r0)
        mov r0, r1
        bl __c_start

.data