1/* SPDX-License-Identifier: GPL-2.0 */ 2/* 3 * Copyright (C) 2020-2022 Loongson Technology Corporation Limited 4 * 5 * Derived from MIPS: 6 * Copyright (C) 1994 - 2000, 2001, 2003 Ralf Baechle 7 * Copyright (C) 1999, 2000 Silicon Graphics, Inc. 8 * Copyright (C) 2001 MIPS Technologies, Inc. 9 */ 10 11#include <asm/asm.h> 12#include <asm/asmmacro.h> 13#include <asm/loongarch.h> 14#include <asm/regdef.h> 15#include <asm/stackframe.h> 16#include <asm/thread_info.h> 17#include <asm/unwind_hints.h> 18 19 .text 20 .cfi_sections .debug_frame 21 .align 5 22SYM_CODE_START(handle_syscall) 23 UNWIND_HINT_UNDEFINED 24 csrrd t0, PERCPU_BASE_KS 25 la.pcrel t1, kernelsp 26 add.d t1, t1, t0 27 move t2, sp 28 ld.d sp, t1, 0 29 30 addi.d sp, sp, -PT_SIZE 31 cfi_st t2, PT_R3 32 cfi_rel_offset sp, PT_R3 33 st.d zero, sp, PT_R0 34 csrrd t2, LOONGARCH_CSR_PRMD 35 st.d t2, sp, PT_PRMD 36 csrrd t2, LOONGARCH_CSR_CRMD 37 st.d t2, sp, PT_CRMD 38 csrrd t2, LOONGARCH_CSR_EUEN 39 st.d t2, sp, PT_EUEN 40 csrrd t2, LOONGARCH_CSR_ECFG 41 st.d t2, sp, PT_ECFG 42 csrrd t2, LOONGARCH_CSR_ESTAT 43 st.d t2, sp, PT_ESTAT 44 cfi_st ra, PT_R1 45 cfi_st a0, PT_R4 46 cfi_st a1, PT_R5 47 cfi_st a2, PT_R6 48 cfi_st a3, PT_R7 49 cfi_st a4, PT_R8 50 cfi_st a5, PT_R9 51 cfi_st a6, PT_R10 52 cfi_st a7, PT_R11 53 csrrd ra, LOONGARCH_CSR_ERA 54 st.d ra, sp, PT_ERA 55 cfi_rel_offset ra, PT_ERA 56 57 cfi_st tp, PT_R2 58 cfi_st u0, PT_R21 59 cfi_st fp, PT_R22 60 61 SAVE_STATIC 62 UNWIND_HINT_REGS 63 64#ifdef CONFIG_KGDB 65 li.w t1, CSR_CRMD_WE 66 csrxchg t1, t1, LOONGARCH_CSR_CRMD 67#endif 68 69 move u0, t0 70 li.d tp, ~_THREAD_MASK 71 and tp, tp, sp 72 73 move a0, sp 74 bl do_syscall 75 76 RESTORE_ALL_AND_RET 77SYM_CODE_END(handle_syscall) 78_ASM_NOKPROBE(handle_syscall) 79 80SYM_CODE_START(ret_from_fork) 81 UNWIND_HINT_REGS 82 bl schedule_tail # a0 = struct task_struct *prev 83 move a0, sp 84 bl syscall_exit_to_user_mode 85 RESTORE_STATIC 86 RESTORE_SOME 87 RESTORE_SP_AND_RET 88SYM_CODE_END(ret_from_fork) 89 90SYM_CODE_START(ret_from_kernel_thread) 91 UNWIND_HINT_REGS 92 bl schedule_tail # a0 = struct task_struct *prev 93 move a0, s1 94 jirl ra, s0, 0 95 move a0, sp 96 bl syscall_exit_to_user_mode 97 RESTORE_STATIC 98 RESTORE_SOME 99 RESTORE_SP_AND_RET 100SYM_CODE_END(ret_from_kernel_thread) 101