diff options
| author | Max Filippov <jcmvbkbc@gmail.com> | 2021-05-02 00:32:58 +0200 |
|---|---|---|
| committer | Max Filippov <jcmvbkbc@gmail.com> | 2021-10-19 07:19:35 +0200 |
| commit | 0b5372570b1f3fcb35255d28e707846e613c27f2 (patch) | |
| tree | 7f38b947b50ad051903ec2d251fb51f3c62bc706 /arch/xtensa/kernel/mcount.S | |
| parent | xtensa: definitions for call0 ABI (diff) | |
| download | linux-0b5372570b1f3fcb35255d28e707846e613c27f2.tar.xz linux-0b5372570b1f3fcb35255d28e707846e613c27f2.zip | |
xtensa: implement call0 ABI support in assembly
Replace hardcoded register and opcode names with ABI-agnostic macros.
Add register save/restore code where necessary. Conditionalize windowed
only or call0 only code. Add stack initialization matching _switch_to
epilogue to copy_thread.
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Diffstat (limited to 'arch/xtensa/kernel/mcount.S')
| -rw-r--r-- | arch/xtensa/kernel/mcount.S | 38 |
1 files changed, 36 insertions, 2 deletions
diff --git a/arch/xtensa/kernel/mcount.S b/arch/xtensa/kernel/mcount.S index 5e4619f52858..51daaf4e0b82 100644 --- a/arch/xtensa/kernel/mcount.S +++ b/arch/xtensa/kernel/mcount.S @@ -17,11 +17,16 @@ /* * Entry condition: * - * a2: a0 of the caller + * 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 @@ -42,7 +47,36 @@ ENTRY(_mcount) 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) ENTRY(ftrace_stub) |