/*
* crt0-tc2x.S -- Startup code for GNU/TriCore applications.
*
* Copyright (C) 1998-2014 HighTec EDV-Systeme GmbH.
*
* This file is part of GCC.
*
* GCC 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 3, or (at your option)
* any later version.
*
* GCC is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* Under Section 7 of GPL version 3, you are granted additional
* permissions described in the GCC Runtime Library Exception, version
* 3.1, as published by the Free Software Foundation.
*
* You should have received a copy of the GNU General Public License and
* a copy of the GCC Runtime Library Exception along with this program;
* see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
* <http://www.gnu.org/licenses/>. */
/* Define the Derivate Name as a hexvalue. This value
* is built-in defined in tricore-c.c (from tricore-devices.c)
* the derivate number as a hexvalue (e.g. TC1796 => 0x1796
* This name will be used in the memory.x Memory description to
* to confirm that the crt0.o and the memory.x will be get from
* same directory
*/
.section ".startup_code", "ax", @progbits
.global _start
.type _start,@function
/* default BMI header (only TC2xxx devices) */
.word 0x00000000
.word 0xb3590070
.word 0x00000000
.word 0x00000000
.word 0x00000000
.word 0x00000000
.word 0x791eb864
.word 0x86e1479b
_start:
.code32
j _startaddr
.align 2
_startaddr:
/*
* initialize user and interrupt stack pointers
*/
movh.a %sp,hi:__USTACK # load %sp
lea %sp,[%sp]lo:__USTACK
movh %d0,hi:__ISTACK # load $isp
addi %d0,%d0,lo:__ISTACK
mtcr $isp,%d0
isync
#; install trap handlers
movh %d0,hi:first_trap_table #; load $btv
addi %d0,%d0,lo:first_trap_table
mtcr $btv,%d0
isync
/*
* initialize call depth counter
*/
mfcr %d0,$psw
or %d0,%d0,0x7f # disable call depth counting
andn %d0,%d0,0x80 # clear CDE bit
mtcr $psw,%d0
isync
/*
* initialize access to system global registers
*/
mfcr %d0,$psw
or %d0,%d0,0x100 # set GW bit
mtcr $psw,%d0
isync
/*
* initialize SDA base pointers
*/
.global _SMALL_DATA_,_SMALL_DATA2_,_SMALL_DATA3_,_SMALL_DATA4_
.weak _SMALL_DATA_,_SMALL_DATA2_,_SMALL_DATA3_,_SMALL_DATA4_
movh.a %a0,hi:_SMALL_DATA_ # %a0 addresses .sdata/.sbss
lea %a0,[%a0]lo:_SMALL_DATA_
movh.a %a1,hi:_SMALL_DATA2_ # %a1 addresses .sdata2/.sbss2
lea %a1,[%a1]lo:_SMALL_DATA2_
movh.a %a8,hi:_SMALL_DATA3_ # %a8 addresses .sdata3/.sbss3
lea %a8,[%a8]lo:_SMALL_DATA3_
movh.a %a9,hi:_SMALL_DATA4_ # %a9 addresses .sdata4/.sbss4
lea %a9,[%a9]lo:_SMALL_DATA4_
/*
* reset access to system global registers
*/
mfcr %d0,$psw
andn %d0,%d0,0x100 # clear GW bit
mtcr $psw,%d0
isync
/*
* initialize context save areas
*/
jl __init_csa
/*
* handle clear table (i.e., fill BSS with zeros)
*/
jl __clear_table_func
/*
* handle copy table (support for romable code)
*/
jl __copy_table_func
/*
* _exit (main (0, NULL));
*/
mov %d4,0 # argc = 0
sub.a %sp,8
st.w [%sp]0,%d4
st.w [%sp]4,%d4
mov.aa %a4,%sp # argv
call main # int retval = main (0, NULL);
mov.a %a14,%d2 # move exit code to match trap handler
j _exit # _exit (retval);
debug # should never come here
/*
* initialize context save areas (CSAs), PCXI, LCX and FCX
*/
.global __init_csa
.type __init_csa,function
__init_csa:
movh %d0,0
mtcr $pcxi,%d0
isync
movh %d0,hi:__CSA_BEGIN #; %d0 = begin of CSA
addi %d0,%d0,lo:__CSA_BEGIN
addi %d0,%d0,63 #; force alignment (2^6)
andn %d0,%d0,63
movh %d2,hi:__CSA_END #; %d2 = end of CSA
addi %d2,%d2,lo:__CSA_END
andn %d2,%d2,63 #; force alignment (2^6)
sub %d2,%d2,%d0
sh %d2,%d2,-6 #; %d2 = number of CSAs
mov.a %a3,%d0 #; %a3 = address of first CSA
extr.u %d0,%d0,28,4 #; %d0 = segment << 16
sh %d0,%d0,16
lea %a4,0 #; %a4 = previous CSA = 0
st.a [%a3],%a4 #; store it in 1st CSA
mov.aa %a4,%a3 #; %a4 = current CSA
lea %a3,[%a3]64 #; %a3 = %a3->nextCSA
mov.d %d1,%a3
extr.u %d1,%d1,6,16 #; get CSA index
or %d1,%d1,%d0 #; add segment number
mtcr $lcx,%d1 #; initialize LCX
add %d2,%d2,-2 #; CSAs to initialize -= 2
mov.a %a5,%d2 #; %a5 = loop counter
csa_loop:
mov.d %d1,%a4 #; %d1 = current CSA address
extr.u %d1,%d1,6,16 #; get CSA index
or %d1,%d1,%d0 #; add segment number
st.w [%a3],%d1 #; store "nextCSA" pointer
mov.aa %a4,%a3 #; %a4 = current CSA address
lea %a3,[%a3]64 #; %a3 = %a3->nextCSA
loop %a5,csa_loop #; repeat until done
mov.d %d1,%a4 #; %d1 = current CSA address
extr.u %d1,%d1,6,16 #; get CSA index
or %d1,%d1,%d0 #; add segment number
mtcr $fcx,%d1 #; initialize FCX
isync
ji %a11
/*
* handle clear table (i.e., fill BSS with zeros)
*/
.global __clear_table_func
.type __clear_table_func,@function
__clear_table_func:
mov %d14,0 # %e14 = 0
mov %d15,0
movh.a %a13,hi:__clear_table # %a13 = &first table entry
lea %a13,[%a13]lo:__clear_table
__clear_table_next:
ld.a %a15,[%a13+]4 # %a15 = current block base
ld.w %d3,[%a13+]4 # %d3 = current block length
jeq %d3,-1,__clear_table_done # length == -1 => end of table
sh %d0,%d3,-3 # %d0 = length / 8 (doublewords)
and %d1,%d3,7 # %d1 = length % 8 (rem. bytes)
jz %d0,__clear_word # block size < 8 => clear word
addi %d0,%d0,-1 # else doublewords -= 1
mov.a %a2,%d0 # %a2 = loop counter
__clear_dword:
st.d [%a15+]8,%e14 # clear one doubleword
loop %a2,__clear_dword
__clear_word:
jz %d1,__clear_table_next
sh %d0,%d1,-2 # %d0 = length / 4 (words)
and %d1,%d1,3 # %d1 = length % 4 (rem. bytes)
jz %d0,__clear_hword # block size < 4 => clear hword
st.w [%a15+]4,%d15 # clear one word
__clear_hword:
jz %d1,__clear_table_next
sh %d0,%d1,-1 # %d0 = length / 2 (halfwords)
and %d1,%d1,1 # %d1 = length % 2 (rem. bytes)
jz %d0,__clear_byte # block size < 2 => clear byte
st.h [%a15+]2,%d15 # clear one halfword
__clear_byte:
jz %d1,__clear_table_next
st.b [%a15],%d15 # clear one byte
j __clear_table_next # handle next clear table entry
__clear_table_done:
ji %a11
/*
* handle copy table (support for romable code)
*/
.global __copy_table_func
.type __copy_table_func,@function
__copy_table_func:
movh.a %a13,hi:__copy_table # %a13 = &first table entry
lea %a13,[%a13]lo:__copy_table
__copy_table_next:
ld.a %a15,[%a13+]4 # %a15 = src address
ld.a %a14,[%a13+]4 # %a14 = dst address
ld.w %d3,[%a13+]4 # %d3 = block length
jeq %d3,-1,__copy_table_done # length == -1 => end of table
sh %d0,%d3,-3 # %d0 = length / 8 (doublewords)
and %d1,%d3,7 # %d1 = length % 8 (rem. bytes)
jz %d0,__copy_word # block size < 8 => copy word
addi %d0,%d0,-1 # else doublewords -= 1
mov.a %a2,%d0 # %a2 = loop counter
__copy_dword:
ld.d %e14,[%a15+]8 # copy one doubleword
st.d [%a14+]8,%e14
loop %a2,__copy_dword
__copy_word:
jz %d1,__copy_table_next
sh %d0,%d1,-2 # %d0 = length / 4 (words)
and %d1,%d1,3 # %d1 = length % 4 (rem. bytes)
jz %d0,__copy_hword # block size < 4 => copy hword
ld.w %d14,[%a15+]4 # copy one word
st.w [%a14+]4,%d14
__copy_hword:
jz %d1,__copy_table_next
sh %d0,%d1,-1 # %d0 = length / 2 (halfwords)
and %d1,%d1,1 # %d1 = length % 2 (rem. bytes)
jz %d0,__copy_byte # block size < 2 => copy byte
ld.h %d14,[%a15+]2 # copy one halfword
st.h [%a14+]2,%d14
__copy_byte:
jz %d1,__copy_table_next
ld.b %d14,[%a15]0 # copy one byte
st.b [%a14],%d14
j __copy_table_next # handle next copy table entry
__copy_table_done:
ji %a11
_exit:
movh.a %a15, hi:__TESTDEVICE
lea %a15,[%a15]lo:__TESTDEVICE
mov.d %d2, %a14
st.w [%a15], %d2 # write exit code to testdevice
debug
/*============================================================================*
* Exception handlers (exceptions in startup code)
*
* This is a minimal trap vector table, which consists of eight
* entries, each consisting of eight words (32 bytes).
*============================================================================*/
#; .section .traptab, "ax", @progbits
.macro trapentry from=0, to=7
mov.u %d14, \from << 8
add %d14,%d14,%d15
mov.a %a14,%d14
addih.a %a14,%a14,0 # if we trap, we fail
j _exit
0:
j 0b
nop
rfe
.align 5
.if \to-\from
trapentry "(\from+1)",\to
.endif
.endm
.align 8
.global first_trap_table
first_trap_table:
trapentry 0, 7