diff options
Diffstat (limited to 'arch/xtensa/kernel/entry.S')
| -rw-r--r-- | arch/xtensa/kernel/entry.S | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S index 9afe8f612f23..9e3676879168 100644 --- a/arch/xtensa/kernel/entry.S +++ b/arch/xtensa/kernel/entry.S @@ -1003,7 +1003,41 @@ ENTRY(fast_alloca) 4: j _WindowUnderflow4 ENDPROC(fast_alloca) +#ifdef CONFIG_USER_ABI_CALL0_PROBE /* + * fast illegal instruction handler. + * + * This is used to fix up user PS.WOE on the exception caused + * by the first opcode related to register window. If PS.WOE is + * already set it goes directly to the common user exception handler. + * + * Entry condition: + * + * a0: trashed, original value saved on stack (PT_AREG0) + * a1: a1 + * a2: new stack pointer, original in DEPC + * a3: a3 + * depc: a2, original value saved on stack (PT_DEPC) + * excsave_1: dispatch table + */ + +ENTRY(fast_illegal_instruction_user) + + rsr a0, ps + bbsi.l a0, PS_WOE_BIT, user_exception + s32i a3, a2, PT_AREG3 + movi a3, PS_WOE_MASK + or a0, a0, a3 + wsr a0, ps + l32i a3, a2, PT_AREG3 + l32i a0, a2, PT_AREG0 + rsr a2, depc + rfe + +ENDPROC(fast_illegal_instruction_user) +#endif + + /* * fast system calls. * * WARNING: The kernel doesn't save the entire user context before |