ack/plat/rpi/boot.s

66 lines
1.3 KiB
ArmAsm

#
/*
* Raspberry Pi support library for the ACK
* © 2013 David Given
* This file is redistributable under the terms of the 3-clause BSD license.
* See the file 'Copying' in the root of the distribution for the full text.
*/
! Declare segments (the order is important).
.sect .text
.sect .rom
.sect .data
.sect .bss
.sect .text
begtext:
lea r15, begtext
st sp, .returnsp
st lr, .returnlr
#if 0
! Wipe the bss. (I'm a little suprised that __m_a_i_n doesn't do this.)
mov di, begbss
mov cx, endbss
sub cx, di
mov ax, 0
rep stosb
! Push standard parameters onto the stack and go.
push envp ! envp
push argv ! argv
push 1 ! argc
#endif
b __m_a_i_n
.define __exit
__exit:
ld sp, .returnsp
ld lr, .returnlr
b lr
! Define symbols at the beginning of our various segments, so that we can find
! them. (Except .text, which has already been done.)
.define begtext, begdata, begbss
.sect .data; begdata:
.sect .rom; begrom:
.sect .bss; begbss:
! Some magic data. All EM systems need these.
.define .trppc, .ignmask, _errno
.comm .trppc, 4
.comm .ignmask, 4
.comm _errno, 4
! We store the stack pointer and return address on entry so that we can
! cleanly exit.
.comm .returnsp, 4
.comm .returnlr, 4