diff options
Diffstat (limited to 'arch/xtensa/kernel/entry.S')
| -rw-r--r-- | arch/xtensa/kernel/entry.S | 122 |
1 files changed, 65 insertions, 57 deletions
diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S index 18453067c25..3777fec85e7 100644 --- a/arch/xtensa/kernel/entry.S +++ b/arch/xtensa/kernel/entry.S @@ -219,6 +219,7 @@ _user_exception: j common_exception +ENDPROC(user_exception) /* * First-level exit handler for kernel exceptions @@ -371,6 +372,13 @@ common_exception: s32i a2, a1, PT_LBEG s32i a3, a1, PT_LEND + /* Save SCOMPARE1 */ + +#if XCHAL_HAVE_S32C1I + rsr a2, scompare1 + s32i a2, a1, PT_SCOMPARE1 +#endif + /* Save optional registers. */ save_xtregs_opt a1 a2 a4 a5 a6 a7 PT_XTREGS_OPT @@ -432,6 +440,12 @@ common_exception_return: load_xtregs_opt a1 a2 a4 a5 a6 a7 PT_XTREGS_OPT + /* Restore SCOMPARE1 */ + +#if XCHAL_HAVE_S32C1I + l32i a2, a1, PT_SCOMPARE1 + wsr a2, scompare1 +#endif wsr a3, ps /* disable interrupts */ _bbci.l a3, PS_UM_BIT, kernel_exception_exit @@ -641,6 +655,8 @@ common_exception_exit: l32i a1, a1, PT_AREG1 rfde +ENDPROC(kernel_exception) + /* * Debug exception handler. * @@ -701,6 +717,7 @@ ENTRY(debug_exception) /* Debug exception while in exception mode. */ 1: j 1b // FIXME!! +ENDPROC(debug_exception) /* * We get here in case of an unrecoverable exception. @@ -751,6 +768,7 @@ ENTRY(unrecoverable_exception) 1: j 1b +ENDPROC(unrecoverable_exception) /* -------------------------- FAST EXCEPTION HANDLERS ----------------------- */ @@ -856,7 +874,7 @@ ENTRY(fast_alloca) _bnei a0, 1, 1f # no 'movsp a1, ax': jump - /* Move the save area. This implies the use of the L32E + /* Move the save area. This implies the use of the L32E * and S32E instructions, because this move must be done with * the user's PS.RING privilege levels, not with ring 0 * (kernel's) privileges currently active with PS.EXCM @@ -929,6 +947,7 @@ ENTRY(fast_alloca) l32i a2, a2, PT_AREG2 rfe +ENDPROC(fast_alloca) /* * fast system calls. @@ -966,6 +985,8 @@ ENTRY(fast_syscall_kernel) j kernel_exception +ENDPROC(fast_syscall_kernel) + ENTRY(fast_syscall_user) /* Skip syscall. */ @@ -983,19 +1004,21 @@ ENTRY(fast_syscall_user) j user_exception -ENTRY(fast_syscall_unrecoverable) +ENDPROC(fast_syscall_user) - /* Restore all states. */ +ENTRY(fast_syscall_unrecoverable) - l32i a0, a2, PT_AREG0 # restore a0 - xsr a2, depc # restore a2, depc - rsr a3, excsave1 + /* Restore all states. */ - wsr a0, excsave1 - movi a0, unrecoverable_exception - callx0 a0 + l32i a0, a2, PT_AREG0 # restore a0 + xsr a2, depc # restore a2, depc + rsr a3, excsave1 + wsr a0, excsave1 + movi a0, unrecoverable_exception + callx0 a0 +ENDPROC(fast_syscall_unrecoverable) /* * sysxtensa syscall handler @@ -1101,7 +1124,7 @@ CATCH movi a2, -EINVAL rfe - +ENDPROC(fast_syscall_xtensa) /* fast_syscall_spill_registers. @@ -1160,6 +1183,8 @@ ENTRY(fast_syscall_spill_registers) movi a2, 0 rfe +ENDPROC(fast_syscall_spill_registers) + /* Fixup handler. * * We get here if the spill routine causes an exception, e.g. tlb miss. @@ -1228,9 +1253,9 @@ fast_syscall_spill_registers_fixup: movi a3, exc_table rsr a0, exccause - addx4 a0, a0, a3 # find entry in table - l32i a0, a0, EXC_TABLE_FAST_USER # load handler - jx a0 + addx4 a0, a0, a3 # find entry in table + l32i a0, a0, EXC_TABLE_FAST_USER # load handler + jx a0 fast_syscall_spill_registers_fixup_return: @@ -1432,7 +1457,7 @@ ENTRY(_spill_registers) rsr a0, ps _bbci.l a0, PS_UM_BIT, 1f - /* User space: Setup a dummy frame and kill application. + /* User space: Setup a dummy frame and kill application. * Note: We assume EXC_TABLE_KSTK contains a valid stack pointer. */ @@ -1464,6 +1489,8 @@ ENTRY(_spill_registers) callx0 a0 # should not return 1: j 1b +ENDPROC(_spill_registers) + #ifdef CONFIG_MMU /* * We should never get here. Bail out! @@ -1475,6 +1502,8 @@ ENTRY(fast_second_level_miss_double_kernel) callx0 a0 # should not return 1: j 1b +ENDPROC(fast_second_level_miss_double_kernel) + /* First-level entry handler for user, kernel, and double 2nd-level * TLB miss exceptions. Note that for now, user and kernel miss * exceptions share the same entry point and are handled identically. @@ -1682,6 +1711,7 @@ ENTRY(fast_second_level_miss) j _kernel_exception 1: j _user_exception +ENDPROC(fast_second_level_miss) /* * StoreProhibitedException @@ -1777,6 +1807,9 @@ ENTRY(fast_store_prohibited) bbsi.l a2, PS_UM_BIT, 1f j _kernel_exception 1: j _user_exception + +ENDPROC(fast_store_prohibited) + #endif /* CONFIG_MMU */ /* @@ -1787,6 +1820,7 @@ ENTRY(fast_store_prohibited) */ ENTRY(system_call) + entry a1, 32 /* regs->syscall = regs->areg[2] */ @@ -1831,50 +1865,8 @@ ENTRY(system_call) callx4 a4 retw +ENDPROC(system_call) -/* - * Create a kernel thread - * - * int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags) - * a2 a2 a3 a4 - */ - -ENTRY(kernel_thread) - entry a1, 16 - - mov a5, a2 # preserve fn over syscall - mov a7, a3 # preserve args over syscall - - movi a3, _CLONE_VM | _CLONE_UNTRACED - movi a2, __NR_clone - or a6, a4, a3 # arg0: flags - mov a3, a1 # arg1: sp - syscall - - beq a3, a1, 1f # branch if parent - mov a6, a7 # args - callx4 a5 # fn(args) - - movi a2, __NR_exit - syscall # return value of fn(args) still in a6 - -1: retw - -/* - * Do a system call from kernel instead of calling sys_execve, so we end up - * with proper pt_regs. - * - * int kernel_execve(const char *fname, char *const argv[], charg *const envp[]) - * a2 a2 a3 a4 - */ - -ENTRY(kernel_execve) - entry a1, 16 - mov a6, a2 # arg0 is in a6 - movi a2, __NR_execve - syscall - - retw /* * Task switch. @@ -1943,6 +1935,7 @@ ENTRY(_switch_to) retw +ENDPROC(_switch_to) ENTRY(ret_from_fork) @@ -1958,3 +1951,18 @@ ENTRY(ret_from_fork) j common_exception_return +ENDPROC(ret_from_fork) + +/* + * Kernel thread creation helper + * On entry, set up by copy_thread: a2 = thread_fn, a3 = thread_fn arg + * left from _switch_to: a6 = prev + */ +ENTRY(ret_from_kernel_thread) + + call4 schedule_tail + mov a6, a3 + callx4 a2 + j common_exception_return + +ENDPROC(ret_from_kernel_thread) |