| /* |
| * arch/xtensa/kernel/mcount.S |
| * |
| * Xtensa specific mcount support |
| * |
| * This file is subject to the terms and conditions of the GNU General Public |
| * License. See the file "COPYING" in the main directory of this archive |
| * for more details. |
| * |
| * Copyright (C) 2013 Tensilica Inc. |
| */ |
| |
| #include <linux/linkage.h> |
| #include <asm/asmmacro.h> |
| #include <asm/ftrace.h> |
| |
| /* |
| * Entry condition: |
| * |
| * a2: a0 of the caller in windowed ABI |
| * a10: a0 of the caller in call0 ABI |
| * |
| * In call0 ABI the function _mcount is called with the special ABI: |
| * its argument is in a10 and all the usual argument registers (a2 - a7) |
| * must be preserved in addition to callee-saved a12 - a15. |
| */ |
| |
| ENTRY(_mcount) |
| #if defined(__XTENSA_WINDOWED_ABI__) |
| abi_entry_default |
| |
| movi a4, ftrace_trace_function |
| l32i a4, a4, 0 |
| movi a3, ftrace_stub |
| bne a3, a4, 1f |
| abi_ret_default |
| |
| 1: xor a7, a2, a1 |
| movi a3, 0x3fffffff |
| and a7, a7, a3 |
| xor a7, a7, a1 |
| |
| xor a6, a0, a1 |
| and a6, a6, a3 |
| xor a6, a6, a1 |
| addi a6, a6, -MCOUNT_INSN_SIZE |
| callx4 a4 |
| |
| abi_ret_default |
| #elif defined(__XTENSA_CALL0_ABI__) |
| abi_entry_default |
| |
| movi a9, ftrace_trace_function |
| l32i a9, a9, 0 |
| movi a11, ftrace_stub |
| bne a9, a11, 1f |
| abi_ret_default |
| |
| 1: abi_entry(28) |
| s32i a0, sp, 0 |
| s32i a2, sp, 4 |
| s32i a3, sp, 8 |
| s32i a4, sp, 12 |
| s32i a5, sp, 16 |
| s32i a6, sp, 20 |
| s32i a7, sp, 24 |
| addi a2, a10, -MCOUNT_INSN_SIZE |
| callx0 a9 |
| l32i a0, sp, 0 |
| l32i a2, sp, 4 |
| l32i a3, sp, 8 |
| l32i a4, sp, 12 |
| l32i a5, sp, 16 |
| l32i a6, sp, 20 |
| l32i a7, sp, 24 |
| abi_ret(28) |
| #else |
| #error Unsupported Xtensa ABI |
| #endif |
| ENDPROC(_mcount) |
| EXPORT_SYMBOL(_mcount) |
| |
| ENTRY(ftrace_stub) |
| abi_entry_default |
| abi_ret_default |
| ENDPROC(ftrace_stub) |
