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|
/* Copyright (C) 2000-2021 Free Software Foundation, Inc.
This file was pretty much copied from newlib.
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/>. */
#include "crt.h"
#ifdef MMU_SUPPORT
/* Section used for exception/timer interrupt stack area */
.section .data.vbr.stack,"aw"
.align 4
.global __ST_VBR
__ST_VBR:
.zero 1024 * 2 /* ; 2k for VBR handlers */
/* Label at the highest stack address where the stack grows from */
__timer_stack:
#endif /* MMU_SUPPORT */
/* ;----------------------------------------
Normal newlib crt1.S */
! make a place to keep any previous value of the vbr register
! this will only have a value if it has been set by redboot (for example)
.section .bss
old_vbr:
.long 0
#ifdef PROFILE
profiling_enabled:
.long 0
#endif
.section .text
.global start
.import ___rtos_profiler_start_timer
.weak ___rtos_profiler_start_timer
start:
mov.l stack_k,r15
#if defined (__SH3__) || (defined (__SH_FPU_ANY__) && ! defined (__SH2E__) && ! defined (__SH2A__)) || defined (__SH4_NOFPU__)
#define VBR_SETUP
! before zeroing the bss ...
! if the vbr is already set to vbr_start then the program has been restarted
! (i.e. it is not the first time the program has been run since reset)
! reset the vbr to its old value before old_vbr (in bss) is wiped
! this ensures that the later code does not create a circular vbr chain
stc vbr, r1
mov.l vbr_start_k, r2
cmp/eq r1, r2
bf 0f
! reset the old vbr value
mov.l old_vbr_k, r1
mov.l @r1, r2
ldc r2, vbr
0:
#endif /* VBR_SETUP */
! zero out bss
mov.l edata_k,r0
mov.l end_k,r1
mov #0,r2
start_l:
mov.l r2,@r0
add #4,r0
cmp/ge r0,r1
bt start_l
#if defined (__SH_FPU_ANY__)
mov.l set_fpscr_k, r1
mov #4,r4
jsr @r1
shll16 r4 ! Set DN bit (flush denormal inputs to zero)
lds r3,fpscr ! Switch to default precision
#endif /* defined (__SH_FPU_ANY__) */
#ifdef VBR_SETUP
! save the existing contents of the vbr
! there will only be a prior value when using something like redboot
! otherwise it will be zero
stc vbr, r1
mov.l old_vbr_k, r2
mov.l r1, @r2
! setup vbr
mov.l vbr_start_k, r1
ldc r1,vbr
#endif /* VBR_SETUP */
! if an rtos is exporting a timer start fn,
! then pick up an SR which does not enable ints
! (the rtos will take care of this)
mov.l rtos_start_fn, r0
mov.l sr_initial_bare, r1
tst r0, r0
bt set_sr
mov.l sr_initial_rtos, r1
set_sr:
! Set status register (sr)
ldc r1, sr
! arrange for exit to call fini
mov.l atexit_k,r0
mov.l fini_k,r4
jsr @r0
nop
#ifdef PROFILE
! arrange for exit to call _mcleanup (via stop_profiling)
mova stop_profiling,r0
mov.l atexit_k,r1
jsr @r1
mov r0, r4
! Call profiler startup code
mov.l monstartup_k, r0
mov.l start_k, r4
mov.l etext_k, r5
jsr @r0
nop
! enable profiling trap
! until now any trap 33s will have been ignored
! This means that all library functions called before this point
! (directly or indirectly) may have the profiling trap at the start.
! Therefore, only mcount itself may not have the extra header.
mov.l profiling_enabled_k2, r0
mov #1, r1
mov.l r1, @r0
#endif /* PROFILE */
! call init
mov.l init_k,r0
jsr @r0
nop
! call the mainline
mov.l main_k,r0
jsr @r0
nop
! call exit
mov r0,r4
mov.l exit_k,r0
jsr @r0
nop
.balign 4
#ifdef PROFILE
stop_profiling:
# stop mcount counting
mov.l profiling_enabled_k2, r0
mov #0, r1
mov.l r1, @r0
# call mcleanup
mov.l mcleanup_k, r0
jmp @r0
nop
.balign 4
mcleanup_k:
.long __mcleanup
monstartup_k:
.long ___monstartup
profiling_enabled_k2:
.long profiling_enabled
start_k:
.long _start
etext_k:
.long __etext
#endif /* PROFILE */
.align 2
#if defined (__SH_FPU_ANY__)
set_fpscr_k:
.long ___set_fpscr
#endif /* defined (__SH_FPU_ANY__) */
stack_k:
.long _stack
edata_k:
.long _edata
end_k:
.long _end
main_k:
.long ___setup_argv_and_call_main
exit_k:
.long _exit
atexit_k:
.long _atexit
init_k:
.long GLOBAL(_init)
fini_k:
.long GLOBAL(_fini)
#ifdef VBR_SETUP
old_vbr_k:
.long old_vbr
vbr_start_k:
.long vbr_start
#endif /* VBR_SETUP */
sr_initial_rtos:
! Privileged mode RB 1 BL 0. Keep BL 0 to allow default trap handlers to work.
! Whether profiling or not, keep interrupts masked,
! the RTOS will enable these if required.
.long 0x600000f1
rtos_start_fn:
.long ___rtos_profiler_start_timer
#ifdef PROFILE
sr_initial_bare:
! Privileged mode RB 1 BL 0. Keep BL 0 to allow default trap handlers to work.
! For bare machine, we need to enable interrupts to get profiling working
.long 0x60000001
#else
sr_initial_bare:
! Privileged mode RB 1 BL 0. Keep BL 0 to allow default trap handlers to work.
! Keep interrupts disabled - the application will enable as required.
.long 0x600000f1
#endif
! supplied for backward compatibility only, in case of linking
! code whose main() was compiled with an older version of GCC.
.global ___main
___main:
rts
nop
#ifdef VBR_SETUP
! Exception handlers
.section .text.vbr, "ax"
vbr_start:
.org 0x100
vbr_100:
#ifdef PROFILE
! Note on register usage.
! we use r0..r3 as scratch in this code. If we are here due to a trapa for profiling
! then this is OK as we are just before executing any function code.
! The other r4..r7 we save explicityl on the stack
! Remaining registers are saved by normal ABI conventions and we assert we do not
! use floating point registers.
mov.l expevt_k1, r1
mov.l @r1, r1
mov.l event_mask, r0
and r0,r1
mov.l trapcode_k, r2
cmp/eq r1,r2
bt 1f
bra handler_100 ! if not a trapa, go to default handler
nop
1:
mov.l trapa_k, r0
mov.l @r0, r0
shlr2 r0 ! trapa code is shifted by 2.
cmp/eq #33, r0
bt 2f
bra handler_100
nop
2:
! If here then it looks like we have trap #33
! Now we need to call mcount with the following convention
! Save and restore r4..r7
mov.l r4,@-r15
mov.l r5,@-r15
mov.l r6,@-r15
mov.l r7,@-r15
sts.l pr,@-r15
! r4 is frompc.
! r5 is selfpc
! r0 is the branch back address.
! The code sequence emitted by gcc for the profiling trap is
! .align 2
! trapa #33
! .align 2
! .long lab Where lab is planted by the compiler. This is the address
! of a datum that needs to be incremented.
sts pr, r4 ! frompc
stc spc, r5 ! selfpc
mov #2, r2
not r2, r2 ! pattern to align to 4
and r2, r5 ! r5 now has aligned address
! add #4, r5 ! r5 now has address of address
mov r5, r2 ! Remember it.
! mov.l @r5, r5 ! r5 has value of lable (lab in above example)
add #8, r2
ldc r2, spc ! our return address avoiding address word
! only call mcount if profiling is enabled
mov.l profiling_enabled_k, r0
mov.l @r0, r0
cmp/eq #0, r0
bt 3f
! call mcount
mov.l mcount_k, r2
jsr @r2
nop
3:
lds.l @r15+,pr
mov.l @r15+,r7
mov.l @r15+,r6
mov.l @r15+,r5
mov.l @r15+,r4
rte
nop
.balign 4
event_mask:
.long 0xfff
trapcode_k:
.long 0x160
expevt_k1:
.long 0xff000024 ! Address of expevt
trapa_k:
.long 0xff000020
mcount_k:
.long __call_mcount
profiling_enabled_k:
.long profiling_enabled
#endif
! Non profiling case.
handler_100:
mov.l 2f, r0 ! load the old vbr setting (if any)
mov.l @r0, r0
cmp/eq #0, r0
bf 1f
! no previous vbr - jump to own generic handler
bra handler
nop
1: ! there was a previous handler - chain them
add #0x7f, r0 ! 0x7f
add #0x7f, r0 ! 0xfe
add #0x2, r0 ! add 0x100 without corrupting another register
jmp @r0
nop
.balign 4
2:
.long old_vbr
.org 0x400
vbr_400: ! Should be at vbr+0x400
mov.l 2f, r0 ! load the old vbr setting (if any)
mov.l @r0, r0
cmp/eq #0, r0
! no previous vbr - jump to own generic handler
bt handler
! there was a previous handler - chain them
rotcr r0
rotcr r0
add #0x7f, r0 ! 0x1fc
add #0x7f, r0 ! 0x3f8
add #0x02, r0 ! 0x400
rotcl r0
rotcl r0 ! Add 0x400 without corrupting another register
jmp @r0
nop
.balign 4
2:
.long old_vbr
handler:
/* If the trap handler is there call it */
mov.l superh_trap_handler_k, r0
cmp/eq #0, r0 ! True if zero.
bf 3f
bra chandler
nop
3:
! Here handler available, call it.
/* Now call the trap handler with as much of the context unchanged as possible.
Move trapping address into PR to make it look like the trap point */
stc spc, r1
lds r1, pr
mov.l expevt_k, r4
mov.l @r4, r4 ! r4 is value of expevt, first parameter.
mov r1, r5 ! Remember trapping pc.
mov r1, r6 ! Remember trapping pc.
mov.l chandler_k, r1
mov.l superh_trap_handler_k, r2
! jmp to trap handler to avoid disturbing pr.
jmp @r2
nop
.org 0x600
vbr_600:
#ifdef PROFILE
! Should be at vbr+0x600
! Now we are in the land of interrupts so need to save more state.
! Save register state
mov.l interrupt_stack_k, r15 ! r15 has been saved to sgr.
mov.l r0,@-r15
mov.l r1,@-r15
mov.l r2,@-r15
mov.l r3,@-r15
mov.l r4,@-r15
mov.l r5,@-r15
mov.l r6,@-r15
mov.l r7,@-r15
sts.l pr,@-r15
sts.l mach,@-r15
sts.l macl,@-r15
#if defined(__SH_FPU_ANY__)
! Save fpul and fpscr, save fr0-fr7 in 64 bit mode
! and set the pervading precision for the timer_handler
mov #0,r0
sts.l fpul,@-r15
sts.l fpscr,@-r15
lds r0,fpscr ! Clear fpscr
fmov fr0,@-r15
fmov fr1,@-r15
fmov fr2,@-r15
fmov fr3,@-r15
mov.l pervading_precision_k,r0
fmov fr4,@-r15
fmov fr5,@-r15
mov.l @r0,r0
fmov fr6,@-r15
fmov fr7,@-r15
lds r0,fpscr
#endif /* __SH_FPU_ANY__ */
! Pass interrupted pc to timer_handler as first parameter (r4).
stc spc, r4
mov.l timer_handler_k, r0
jsr @r0
nop
#if defined(__SH_FPU_ANY__)
mov #0,r0
lds r0,fpscr ! Clear the fpscr
fmov @r15+,fr7
fmov @r15+,fr6
fmov @r15+,fr5
fmov @r15+,fr4
fmov @r15+,fr3
fmov @r15+,fr2
fmov @r15+,fr1
fmov @r15+,fr0
lds.l @r15+,fpscr
lds.l @r15+,fpul
#endif /* __SH_FPU_ANY__ */
lds.l @r15+,macl
lds.l @r15+,mach
lds.l @r15+,pr
mov.l @r15+,r7
mov.l @r15+,r6
mov.l @r15+,r5
mov.l @r15+,r4
mov.l @r15+,r3
mov.l @r15+,r2
mov.l @r15+,r1
mov.l @r15+,r0
stc sgr, r15 ! Restore r15, destroyed by this sequence.
rte
nop
#if defined(__SH_FPU_ANY__)
.balign 4
pervading_precision_k:
.long GLOBAL(__fpscr_values)+4
#endif
#else
mov.l 2f, r0 ! Load the old vbr setting (if any).
mov.l @r0, r0
cmp/eq #0, r0
! no previous vbr - jump to own handler
bt chandler
! there was a previous handler - chain them
rotcr r0
rotcr r0
add #0x7f, r0 ! 0x1fc
add #0x7f, r0 ! 0x3f8
add #0x7f, r0 ! 0x5f4
add #0x03, r0 ! 0x600
rotcl r0
rotcl r0 ! Add 0x600 without corrupting another register
jmp @r0
nop
.balign 4
2:
.long old_vbr
#endif /* PROFILE code */
chandler:
mov.l expevt_k, r4
mov.l @r4, r4 ! r4 is value of expevt hence making this the return code
mov.l handler_exit_k,r0
jsr @r0
nop
! We should never return from _exit but in case we do we would enter the
! the following tight loop
limbo:
bra limbo
nop
.balign 4
#ifdef PROFILE
interrupt_stack_k:
.long __timer_stack ! The high end of the stack
timer_handler_k:
.long __profil_counter
#endif
expevt_k:
.long 0xff000024 ! Address of expevt
chandler_k:
.long chandler
superh_trap_handler_k:
.long __superh_trap_handler
handler_exit_k:
.long _exit
.align 2
! Simulated compile of trap handler.
.section .debug_abbrev,"",@progbits
.Ldebug_abbrev0:
.section .debug_info,"",@progbits
.Ldebug_info0:
.section .debug_line,"",@progbits
.Ldebug_line0:
.text
.Ltext0:
.align 5
.type __superh_trap_handler,@function
__superh_trap_handler:
.LFB1:
mov.l r14,@-r15
.LCFI0:
add #-4,r15
.LCFI1:
mov r15,r14
.LCFI2:
mov.l r4,@r14
lds r1, pr
add #4,r14
mov r14,r15
mov.l @r15+,r14
rts
nop
.LFE1:
.Lfe1:
.size __superh_trap_handler,.Lfe1-__superh_trap_handler
.section .debug_frame,"",@progbits
.Lframe0:
.ualong .LECIE0-.LSCIE0
.LSCIE0:
.ualong 0xffffffff
.byte 0x1
.string ""
.uleb128 0x1
.sleb128 -4
.byte 0x11
.byte 0xc
.uleb128 0xf
.uleb128 0x0
.align 2
.LECIE0:
.LSFDE0:
.ualong .LEFDE0-.LASFDE0
.LASFDE0:
.ualong .Lframe0
.ualong .LFB1
.ualong .LFE1-.LFB1
.byte 0x4
.ualong .LCFI0-.LFB1
.byte 0xe
.uleb128 0x4
.byte 0x4
.ualong .LCFI1-.LCFI0
.byte 0xe
.uleb128 0x8
.byte 0x8e
.uleb128 0x1
.byte 0x4
.ualong .LCFI2-.LCFI1
.byte 0xd
.uleb128 0xe
.align 2
.LEFDE0:
.text
.Letext0:
.section .debug_info
.ualong 0xb3
.uaword 0x2
.ualong .Ldebug_abbrev0
.byte 0x4
.uleb128 0x1
.ualong .Ldebug_line0
.ualong .Letext0
.ualong .Ltext0
.string "trap_handler.c"
.string "xxxxxxxxxxxxxxxxxxxxxxxxxxxx"
.string "GNU C 3.2 20020529 (experimental)"
.byte 0x1
.uleb128 0x2
.ualong 0xa6
.byte 0x1
.string "_superh_trap_handler"
.byte 0x1
.byte 0x2
.byte 0x1
.ualong .LFB1
.ualong .LFE1
.byte 0x1
.byte 0x5e
.uleb128 0x3
.string "trap_reason"
.byte 0x1
.byte 0x1
.ualong 0xa6
.byte 0x2
.byte 0x91
.sleb128 0
.byte 0x0
.uleb128 0x4
.string "unsigned int"
.byte 0x4
.byte 0x7
.byte 0x0
.section .debug_abbrev
.uleb128 0x1
.uleb128 0x11
.byte 0x1
.uleb128 0x10
.uleb128 0x6
.uleb128 0x12
.uleb128 0x1
.uleb128 0x11
.uleb128 0x1
.uleb128 0x3
.uleb128 0x8
.uleb128 0x1b
.uleb128 0x8
.uleb128 0x25
.uleb128 0x8
.uleb128 0x13
.uleb128 0xb
.byte 0x0
.byte 0x0
.uleb128 0x2
.uleb128 0x2e
.byte 0x1
.uleb128 0x1
.uleb128 0x13
.uleb128 0x3f
.uleb128 0xc
.uleb128 0x3
.uleb128 0x8
.uleb128 0x3a
.uleb128 0xb
.uleb128 0x3b
.uleb128 0xb
.uleb128 0x27
.uleb128 0xc
.uleb128 0x11
.uleb128 0x1
.uleb128 0x12
.uleb128 0x1
.uleb128 0x40
.uleb128 0xa
.byte 0x0
.byte 0x0
.uleb128 0x3
.uleb128 0x5
.byte 0x0
.uleb128 0x3
.uleb128 0x8
.uleb128 0x3a
.uleb128 0xb
.uleb128 0x3b
.uleb128 0xb
.uleb128 0x49
.uleb128 0x13
.uleb128 0x2
.uleb128 0xa
.byte 0x0
.byte 0x0
.uleb128 0x4
.uleb128 0x24
.byte 0x0
.uleb128 0x3
.uleb128 0x8
.uleb128 0xb
.uleb128 0xb
.uleb128 0x3e
.uleb128 0xb
.byte 0x0
.byte 0x0
.byte 0x0
.section .debug_pubnames,"",@progbits
.ualong 0x27
.uaword 0x2
.ualong .Ldebug_info0
.ualong 0xb7
.ualong 0x67
.string "_superh_trap_handler"
.ualong 0x0
.section .debug_aranges,"",@progbits
.ualong 0x1c
.uaword 0x2
.ualong .Ldebug_info0
.byte 0x4
.byte 0x0
.uaword 0x0
.uaword 0x0
.ualong .Ltext0
.ualong .Letext0-.Ltext0
.ualong 0x0
.ualong 0x0
#endif /* VBR_SETUP */
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