/* * 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 * . */ /* 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 = lenght % 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 = lenght % 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