| /* SPDX-License-Identifier: GPL-2.0 */ |
| /* |
| * Copyright (C) 2020-2022 Loongson Technology Corporation Limited |
| */ |
| |
| #include <asm/alternative-asm.h> |
| #include <asm/asm.h> |
| #include <asm/asmmacro.h> |
| #include <asm/asm-extable.h> |
| #include <asm/cpu.h> |
| #include <asm/export.h> |
| #include <asm/regdef.h> |
| |
| .irp to, 0, 1, 2, 3, 4, 5, 6, 7 |
| .L_fixup_handle_\to\(): |
| addi.d a0, a1, (\to) * (-8) |
| jr ra |
| .endr |
| |
| SYM_FUNC_START(__clear_user) |
| /* |
| * Some CPUs support hardware unaligned access |
| */ |
| ALTERNATIVE "b __clear_user_generic", \ |
| "b __clear_user_fast", CPU_FEATURE_UAL |
| SYM_FUNC_END(__clear_user) |
| |
| EXPORT_SYMBOL(__clear_user) |
| |
| /* |
| * unsigned long __clear_user_generic(void *addr, size_t size) |
| * |
| * a0: addr |
| * a1: size |
| */ |
| SYM_FUNC_START(__clear_user_generic) |
| beqz a1, 2f |
| |
| 1: st.b zero, a0, 0 |
| addi.d a0, a0, 1 |
| addi.d a1, a1, -1 |
| bgtz a1, 1b |
| |
| 2: move a0, a1 |
| jr ra |
| |
| _asm_extable 1b, .L_fixup_handle_0 |
| SYM_FUNC_END(__clear_user_generic) |
| |
| /* |
| * unsigned long __clear_user_fast(void *addr, unsigned long size) |
| * |
| * a0: addr |
| * a1: size |
| */ |
| SYM_FUNC_START(__clear_user_fast) |
| beqz a1, 10f |
| |
| ori a2, zero, 64 |
| blt a1, a2, 9f |
| |
| /* set 64 bytes at a time */ |
| 1: st.d zero, a0, 0 |
| 2: st.d zero, a0, 8 |
| 3: st.d zero, a0, 16 |
| 4: st.d zero, a0, 24 |
| 5: st.d zero, a0, 32 |
| 6: st.d zero, a0, 40 |
| 7: st.d zero, a0, 48 |
| 8: st.d zero, a0, 56 |
| |
| addi.d a0, a0, 64 |
| addi.d a1, a1, -64 |
| bge a1, a2, 1b |
| |
| beqz a1, 10f |
| |
| /* set the remaining bytes */ |
| 9: st.b zero, a0, 0 |
| addi.d a0, a0, 1 |
| addi.d a1, a1, -1 |
| bgt a1, zero, 9b |
| |
| /* return */ |
| 10: move a0, a1 |
| jr ra |
| |
| /* fixup and ex_table */ |
| _asm_extable 1b, .L_fixup_handle_0 |
| _asm_extable 2b, .L_fixup_handle_1 |
| _asm_extable 3b, .L_fixup_handle_2 |
| _asm_extable 4b, .L_fixup_handle_3 |
| _asm_extable 5b, .L_fixup_handle_4 |
| _asm_extable 6b, .L_fixup_handle_5 |
| _asm_extable 7b, .L_fixup_handle_6 |
| _asm_extable 8b, .L_fixup_handle_7 |
| _asm_extable 9b, .L_fixup_handle_0 |
| SYM_FUNC_END(__clear_user_fast) |