X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=arch%2Fxtensa%2Fkernel%2Fentry.S;h=9e271ba009bfd88645008e0adca5d7b3e87a4e0d;hb=refs%2Fheads%2Fvserver;hp=5c018c503dfa0d465d93a3f322a62a18159fd46c;hpb=76828883507a47dae78837ab5dec5a5b4513c667;p=linux-2.6.git diff --git a/arch/xtensa/kernel/entry.S b/arch/xtensa/kernel/entry.S index 5c018c503..9e271ba00 100644 --- a/arch/xtensa/kernel/entry.S +++ b/arch/xtensa/kernel/entry.S @@ -24,7 +24,7 @@ #include #include #include -#include +#include /* Unimplemented features. */ @@ -364,7 +364,7 @@ common_exception: movi a2, 1 extui a3, a3, 0, 1 # a3 = PS.INTLEVEL[0] moveqz a3, a2, a0 # a3 = 1 iff interrupt exception - movi a2, PS_WOE_MASK + movi a2, 1 << PS_WOE_BIT or a3, a3, a2 rsr a0, EXCCAUSE xsr a3, PS @@ -399,7 +399,7 @@ common_exception_return: /* Jump if we are returning from kernel exceptions. */ 1: l32i a3, a1, PT_PS - _bbsi.l a3, PS_UM_SHIFT, 2f + _bbsi.l a3, PS_UM_BIT, 2f j kernel_exception_exit /* Specific to a user exception exit: @@ -422,7 +422,7 @@ common_exception_return: * (Hint: There is only one user exception frame on stack) */ - movi a3, PS_WOE_MASK + movi a3, 1 << PS_WOE_BIT _bbsi.l a4, TIF_NEED_RESCHED, 3f _bbci.l a4, TIF_SIGPENDING, 4f @@ -694,7 +694,7 @@ common_exception_exit: ENTRY(debug_exception) rsr a0, EPS + XCHAL_DEBUGLEVEL - bbsi.l a0, PS_EXCM_SHIFT, 1f # exception mode + bbsi.l a0, PS_EXCM_BIT, 1f # exception mode /* Set EPC_1 and EXCCAUSE */ @@ -707,7 +707,7 @@ ENTRY(debug_exception) /* Restore PS to the value before the debug exc but with PS.EXCM set.*/ - movi a2, 1 << PS_EXCM_SHIFT + movi a2, 1 << PS_EXCM_BIT or a2, a0, a2 movi a0, debug_exception # restore a3, debug jump vector wsr a2, PS @@ -715,7 +715,7 @@ ENTRY(debug_exception) /* Switch to kernel/user stack, restore jump vector, and save a0 */ - bbsi.l a2, PS_UM_SHIFT, 2f # jump if user mode + bbsi.l a2, PS_UM_BIT, 2f # jump if user mode addi a2, a1, -16-PT_SIZE # assume kernel stack s32i a0, a2, PT_AREG0 @@ -778,7 +778,7 @@ ENTRY(unrecoverable_exception) wsr a1, WINDOWBASE rsync - movi a1, PS_WOE_MASK | 1 + movi a1, (1 << PS_WOE_BIT) | 1 wsr a1, PS rsync @@ -1004,13 +1004,10 @@ ENTRY(fast_syscall_kernel) rsr a0, DEPC # get syscall-nr _beqz a0, fast_syscall_spill_registers - - addi a0, a0, -__NR_sysxtensa - _beqz a0, fast_syscall_sysxtensa + _beqi a0, __NR_xtensa, fast_syscall_xtensa j kernel_exception - ENTRY(fast_syscall_user) /* Skip syscall. */ @@ -1024,9 +1021,7 @@ ENTRY(fast_syscall_user) rsr a0, DEPC # get syscall-nr _beqz a0, fast_syscall_spill_registers - - addi a0, a0, -__NR_sysxtensa - _beqz a0, fast_syscall_sysxtensa + _beqi a0, __NR_xtensa, fast_syscall_xtensa j user_exception @@ -1047,18 +1042,19 @@ ENTRY(fast_syscall_unrecoverable) /* * sysxtensa syscall handler * - * int sysxtensa (XTENSA_ATOMIC_SET, ptr, val, unused); - * int sysxtensa (XTENSA_ATOMIC_ADD, ptr, val, unused); - * int sysxtensa (XTENSA_ATOMIC_EXG_ADD, ptr, val, unused); - * int sysxtensa (XTENSA_ATOMIC_CMP_SWP, ptr, oldval, newval); - * a2 a6 a3 a4 a5 + * int sysxtensa (SYS_XTENSA_ATOMIC_SET, ptr, val, unused); + * int sysxtensa (SYS_XTENSA_ATOMIC_ADD, ptr, val, unused); + * int sysxtensa (SYS_XTENSA_ATOMIC_EXG_ADD, ptr, val, unused); + * int sysxtensa (SYS_XTENSA_ATOMIC_CMP_SWP, ptr, oldval, newval); + * a2 a6 a3 a4 a5 * * Entry condition: * - * a0: trashed, original value saved on stack (PT_AREG0) + * a0: a2 (syscall-nr), original value saved on stack (PT_AREG0) * a1: a1 - * a2: new stack pointer, original in DEPC - * a3: dispatch table + * a2: new stack pointer, original in a0 and DEPC + * a3: dispatch table, original in excsave_1 + * a4..a15: unchanged * depc: a2, original value saved on stack (PT_DEPC) * excsave_1: a3 * @@ -1091,59 +1087,62 @@ ENTRY(fast_syscall_unrecoverable) #define CATCH \ 67: -ENTRY(fast_syscall_sysxtensa) - - _beqz a6, 1f - _blti a6, SYSXTENSA_COUNT, 2f +ENTRY(fast_syscall_xtensa) -1: j user_exception - -2: xsr a3, EXCSAVE_1 # restore a3, excsave1 - s32i a7, a2, PT_AREG7 + xsr a3, EXCSAVE_1 # restore a3, excsave1 + s32i a7, a2, PT_AREG7 # we need an additional register movi a7, 4 # sizeof(unsigned int) - verify_area a3, a7, a0, a2, .Leac + access_ok a3, a7, a0, a2, .Leac # a0: scratch reg, a2: sp - _beqi a6, SYSXTENSA_ATOMIC_SET, .Lset - _beqi a6, SYSXTENSA_ATOMIC_EXG_ADD, .Lexg - _beqi a6, SYSXTENSA_ATOMIC_ADD, .Ladd + addi a6, a6, -1 # assuming SYS_XTENSA_ATOMIC_SET = 1 + _bgeui a6, SYS_XTENSA_COUNT - 1, .Lill + _bnei a6, SYS_XTENSA_ATOMIC_CMP_SWP - 1, .Lnswp - /* Fall through for SYSXTENSA_ATOMIC_CMP_SWP */ + /* Fall through for ATOMIC_CMP_SWP. */ .Lswp: /* Atomic compare and swap */ -TRY l32i a7, a3, 0 # read old value - bne a7, a4, 1f # same as old value? jump - s32i a5, a3, 0 # different, modify value - movi a7, 1 # and return 1 - j .Lret - -1: movi a7, 0 # same values: return 0 - j .Lret - -.Ladd: /* Atomic add */ -.Lexg: /* Atomic (exchange) add */ +TRY l32i a0, a3, 0 # read old value + bne a0, a4, 1f # same as old value? jump +TRY s32i a5, a3, 0 # different, modify value + l32i a7, a2, PT_AREG7 # restore a7 + l32i a0, a2, PT_AREG0 # restore a0 + movi a2, 1 # and return 1 + addi a6, a6, 1 # restore a6 (really necessary?) + rfe -TRY l32i a7, a3, 0 - add a4, a4, a7 - s32i a4, a3, 0 - j .Lret +1: l32i a7, a2, PT_AREG7 # restore a7 + l32i a0, a2, PT_AREG0 # restore a0 + movi a2, 0 # return 0 (note that we cannot set + addi a6, a6, 1 # restore a6 (really necessary?) + rfe -.Lset: /* Atomic set */ +.Lnswp: /* Atomic set, add, and exg_add. */ -TRY l32i a7, a3, 0 # read old value as return value - s32i a4, a3, 0 # write new value +TRY l32i a7, a3, 0 # orig + add a0, a4, a7 # + arg + moveqz a0, a4, a6 # set +TRY s32i a0, a3, 0 # write new value -.Lret: mov a0, a2 + mov a0, a2 mov a2, a7 - l32i a7, a0, PT_AREG7 - l32i a3, a0, PT_AREG3 - l32i a0, a0, PT_AREG0 + l32i a7, a0, PT_AREG7 # restore a7 + l32i a0, a0, PT_AREG0 # restore a0 + addi a6, a6, 1 # restore a6 (really necessary?) rfe CATCH -.Leac: movi a7, -EFAULT - j .Lret +.Leac: l32i a7, a2, PT_AREG7 # restore a7 + l32i a0, a2, PT_AREG0 # restore a0 + movi a2, -EFAULT + rfe + +.Lill: l32i a7, a2, PT_AREG0 # restore a7 + l32i a0, a2, PT_AREG0 # restore a0 + movi a2, -EINVAL + rfe + @@ -1491,7 +1490,7 @@ ENTRY(_spill_registers) */ rsr a0, PS - _bbci.l a0, PS_UM_SHIFT, 1f + _bbci.l a0, PS_UM_BIT, 1f /* User space: Setup a dummy frame and kill application. * Note: We assume EXC_TABLE_KSTK contains a valid stack pointer. @@ -1510,7 +1509,7 @@ ENTRY(_spill_registers) l32i a1, a3, EXC_TABLE_KSTK wsr a3, EXCSAVE_1 - movi a4, PS_WOE_MASK | 1 + movi a4, (1 << PS_WOE_BIT) | 1 wsr a4, PS rsync @@ -1612,7 +1611,7 @@ ENTRY(fast_second_level_miss) rsr a1, PTEVADDR srli a1, a1, PAGE_SHIFT slli a1, a1, PAGE_SHIFT # ptevaddr & PAGE_MASK - addi a1, a1, DTLB_WAY_PGTABLE # ... + way_number + addi a1, a1, DTLB_WAY_PGD # ... + way_number wdtlb a0, a1 dsync @@ -1654,7 +1653,7 @@ ENTRY(fast_second_level_miss) mov a1, a2 rsr a2, PS - bbsi.l a2, PS_UM_SHIFT, 1f + bbsi.l a2, PS_UM_BIT, 1f j _kernel_exception 1: j _user_exception @@ -1753,7 +1752,7 @@ ENTRY(fast_store_prohibited) mov a1, a2 rsr a2, PS - bbsi.l a2, PS_UM_SHIFT, 1f + bbsi.l a2, PS_UM_BIT, 1f j _kernel_exception 1: j _user_exception @@ -1906,6 +1905,103 @@ ENTRY(fast_coprocessor) #endif /* XCHAL_EXTRA_SA_SIZE */ +/* + * System Calls. + * + * void system_call (struct pt_regs* regs, int exccause) + * a2 a3 + */ + +ENTRY(system_call) + entry a1, 32 + + /* regs->syscall = regs->areg[2] */ + + l32i a3, a2, PT_AREG2 + mov a6, a2 + movi a4, do_syscall_trace_enter + s32i a3, a2, PT_SYSCALL + callx4 a4 + + /* syscall = sys_call_table[syscall_nr] */ + + movi a4, sys_call_table; + movi a5, __NR_syscall_count + movi a6, -ENOSYS + bgeu a3, a5, 1f + + addx4 a4, a3, a4 + l32i a4, a4, 0 + movi a5, sys_ni_syscall; + beq a4, a5, 1f + + /* Load args: arg0 - arg5 are passed via regs. */ + + l32i a6, a2, PT_AREG6 + l32i a7, a2, PT_AREG3 + l32i a8, a2, PT_AREG4 + l32i a9, a2, PT_AREG5 + l32i a10, a2, PT_AREG8 + l32i a11, a2, PT_AREG9 + + /* Pass one additional argument to the syscall: pt_regs (on stack) */ + s32i a2, a1, 0 + + callx4 a4 + +1: /* regs->areg[2] = return_value */ + + s32i a6, a2, PT_AREG2 + movi a4, do_syscall_trace_leave + mov a6, a2 + callx4 a4 + retw + + +/* + * 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. * @@ -1924,7 +2020,7 @@ ENTRY(_switch_to) /* Disable ints while we manipulate the stack pointer; spill regs. */ - movi a5, PS_EXCM_MASK | LOCKLEVEL + movi a5, (1 << PS_EXCM_BIT) | LOCKLEVEL xsr a5, PS rsr a3, EXCSAVE_1 rsync @@ -1964,33 +2060,9 @@ ENTRY(ret_from_fork) movi a4, schedule_tail callx4 a4 - movi a4, do_syscall_trace + movi a4, do_syscall_trace_leave + mov a6, a1 callx4 a4 j common_exception_return - - -/* - * Table of syscalls - */ - -.data -.align 4 -.global sys_call_table -sys_call_table: - -#define SYSCALL(call, narg) .word call -#include "syscalls.h" - -/* - * Number of arguments of each syscall - */ - -.global sys_narg_table -sys_narg_table: - -#undef SYSCALL -#define SYSCALL(call, narg) .byte narg -#include "syscalls.h" -