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linux/arch/loongarch/kernel/genex.S
Tiezhu Yang cb8a2ef084 LoongArch: Add ORC stack unwinder support
The kernel CONFIG_UNWINDER_ORC option enables the ORC unwinder, which is
similar in concept to a DWARF unwinder. The difference is that the format
of the ORC data is much simpler than DWARF, which in turn allows the ORC
unwinder to be much simpler and faster.

The ORC data consists of unwind tables which are generated by objtool.
After analyzing all the code paths of a .o file, it determines information
about the stack state at each instruction address in the file and outputs
that information to the .orc_unwind and .orc_unwind_ip sections.

The per-object ORC sections are combined at link time and are sorted and
post-processed at boot time. The unwinder uses the resulting data to
correlate instruction addresses with their stack states at run time.

Most of the logic are similar with x86, in order to get ra info before ra
is saved into stack, add ra_reg and ra_offset into orc_entry. At the same
time, modify some arch-specific code to silence the objtool warnings.

Co-developed-by: Jinyang He <hejinyang@loongson.cn>
Signed-off-by: Jinyang He <hejinyang@loongson.cn>
Co-developed-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
2024-03-11 22:23:47 +08:00

106 lines
2.2 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 2020-2022 Loongson Technology Corporation Limited
*
* Derived from MIPS:
* Copyright (C) 1994 - 2000, 2001, 2003 Ralf Baechle
* Copyright (C) 1999, 2000 Silicon Graphics, Inc.
* Copyright (C) 2002, 2007 Maciej W. Rozycki
* Copyright (C) 2001, 2012 MIPS Technologies, Inc. All rights reserved.
*/
#include <asm/asm.h>
#include <asm/asmmacro.h>
#include <asm/loongarch.h>
#include <asm/regdef.h>
#include <asm/fpregdef.h>
#include <asm/stackframe.h>
#include <asm/thread_info.h>
.align 5
SYM_FUNC_START(__arch_cpu_idle)
/* start of rollback region */
LONG_L t0, tp, TI_FLAGS
nop
andi t0, t0, _TIF_NEED_RESCHED
bnez t0, 1f
nop
nop
nop
idle 0
/* end of rollback region */
1: jr ra
SYM_FUNC_END(__arch_cpu_idle)
SYM_CODE_START(handle_vint)
UNWIND_HINT_UNDEFINED
BACKUP_T0T1
SAVE_ALL
la_abs t1, __arch_cpu_idle
LONG_L t0, sp, PT_ERA
/* 32 byte rollback region */
ori t0, t0, 0x1f
xori t0, t0, 0x1f
bne t0, t1, 1f
LONG_S t0, sp, PT_ERA
1: move a0, sp
move a1, sp
la_abs t0, do_vint
jirl ra, t0, 0
RESTORE_ALL_AND_RET
SYM_CODE_END(handle_vint)
SYM_CODE_START(except_vec_cex)
UNWIND_HINT_UNDEFINED
b cache_parity_error
SYM_CODE_END(except_vec_cex)
.macro build_prep_badv
csrrd t0, LOONGARCH_CSR_BADV
PTR_S t0, sp, PT_BVADDR
.endm
.macro build_prep_fcsr
movfcsr2gr a1, fcsr0
.endm
.macro build_prep_none
.endm
.macro BUILD_HANDLER exception handler prep
.align 5
SYM_CODE_START(handle_\exception)
UNWIND_HINT_UNDEFINED
666:
BACKUP_T0T1
SAVE_ALL
build_prep_\prep
move a0, sp
la_abs t0, do_\handler
jirl ra, t0, 0
668:
RESTORE_ALL_AND_RET
SYM_CODE_END(handle_\exception)
.pushsection ".data", "aw", %progbits
SYM_DATA(unwind_hint_\exception, .word 668b - 666b)
.popsection
.endm
BUILD_HANDLER ade ade badv
BUILD_HANDLER ale ale badv
BUILD_HANDLER bce bce none
BUILD_HANDLER bp bp none
BUILD_HANDLER fpe fpe fcsr
BUILD_HANDLER fpu fpu none
BUILD_HANDLER lsx lsx none
BUILD_HANDLER lasx lasx none
BUILD_HANDLER lbt lbt none
BUILD_HANDLER ri ri none
BUILD_HANDLER watch watch none
BUILD_HANDLER reserved reserved none /* others */
SYM_CODE_START(handle_sys)
UNWIND_HINT_UNDEFINED
la_abs t0, handle_syscall
jr t0
SYM_CODE_END(handle_sys)