4 * Copyright (c) 2005-2007 CodeSourcery, LLC
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
19 #include "qemu/osdep.h"
21 #include "qemu/main-loop.h"
23 #include "exec/helper-proto.h"
24 #include "internals.h"
25 #include "exec/exec-all.h"
26 #include "exec/cpu_ldst.h"
28 #define SIGNBIT (uint32_t)0x80000000
29 #define SIGNBIT64 ((uint64_t)1 << 63)
31 static void raise_exception(CPUARMState
*env
, uint32_t excp
,
32 uint32_t syndrome
, uint32_t target_el
)
34 CPUState
*cs
= CPU(arm_env_get_cpu(env
));
36 if ((env
->cp15
.hcr_el2
& HCR_TGE
) &&
37 target_el
== 1 && !arm_is_secure(env
)) {
39 * Redirect NS EL1 exceptions to NS EL2. These are reported with
40 * their original syndrome register value, with the exception of
41 * SIMD/FP access traps, which are reported as uncategorized
42 * (see DDI0478C.a D1.10.4)
45 if (syndrome
>> ARM_EL_EC_SHIFT
== EC_ADVSIMDFPACCESSTRAP
) {
46 syndrome
= syn_uncategorized();
50 assert(!excp_is_internal(excp
));
51 cs
->exception_index
= excp
;
52 env
->exception
.syndrome
= syndrome
;
53 env
->exception
.target_el
= target_el
;
57 static int exception_target_el(CPUARMState
*env
)
59 int target_el
= MAX(1, arm_current_el(env
));
61 /* No such thing as secure EL1 if EL3 is aarch32, so update the target EL
62 * to EL3 in this case.
64 if (arm_is_secure(env
) && !arm_el_is_aa64(env
, 3) && target_el
== 1) {
71 uint32_t HELPER(neon_tbl
)(uint32_t ireg
, uint32_t def
, void *vn
,
78 for (shift
= 0; shift
< 32; shift
+= 8) {
79 uint32_t index
= (ireg
>> shift
) & 0xff;
80 if (index
< maxindex
) {
81 uint32_t tmp
= (table
[index
>> 3] >> ((index
& 7) << 3)) & 0xff;
84 val
|= def
& (0xff << shift
);
90 #if !defined(CONFIG_USER_ONLY)
92 static inline uint32_t merge_syn_data_abort(uint32_t template_syn
,
93 unsigned int target_el
,
94 bool same_el
, bool ea
,
95 bool s1ptw
, bool is_write
,
100 /* ISV is only set for data aborts routed to EL2 and
101 * never for stage-1 page table walks faulting on stage 2.
103 * Furthermore, ISV is only set for certain kinds of load/stores.
104 * If the template syndrome does not have ISV set, we should leave
107 * See ARMv8 specs, D7-1974:
108 * ISS encoding for an exception from a Data Abort, the
111 if (!(template_syn
& ARM_EL_ISV
) || target_el
!= 2 || s1ptw
) {
112 syn
= syn_data_abort_no_iss(same_el
,
113 ea
, 0, s1ptw
, is_write
, fsc
);
115 /* Fields: IL, ISV, SAS, SSE, SRT, SF and AR come from the template
116 * syndrome created at translation time.
117 * Now we create the runtime syndrome with the remaining fields.
119 syn
= syn_data_abort_with_iss(same_el
,
121 ea
, 0, s1ptw
, is_write
, fsc
,
123 /* Merge the runtime syndrome with the template syndrome. */
129 static void deliver_fault(ARMCPU
*cpu
, vaddr addr
, MMUAccessType access_type
,
130 int mmu_idx
, ARMMMUFaultInfo
*fi
)
132 CPUARMState
*env
= &cpu
->env
;
135 uint32_t syn
, exc
, fsr
, fsc
;
136 ARMMMUIdx arm_mmu_idx
= core_to_arm_mmu_idx(env
, mmu_idx
);
138 target_el
= exception_target_el(env
);
141 env
->cp15
.hpfar_el2
= extract64(fi
->s2addr
, 12, 47) << 4;
143 same_el
= (arm_current_el(env
) == target_el
);
145 if (target_el
== 2 || arm_el_is_aa64(env
, target_el
) ||
146 arm_s1_regime_using_lpae_format(env
, arm_mmu_idx
)) {
147 /* LPAE format fault status register : bottom 6 bits are
148 * status code in the same form as needed for syndrome
150 fsr
= arm_fi_to_lfsc(fi
);
151 fsc
= extract32(fsr
, 0, 6);
153 fsr
= arm_fi_to_sfsc(fi
);
154 /* Short format FSR : this fault will never actually be reported
155 * to an EL that uses a syndrome register. Use a (currently)
156 * reserved FSR code in case the constructed syndrome does leak
157 * into the guest somehow.
162 if (access_type
== MMU_INST_FETCH
) {
163 syn
= syn_insn_abort(same_el
, fi
->ea
, fi
->s1ptw
, fsc
);
164 exc
= EXCP_PREFETCH_ABORT
;
166 syn
= merge_syn_data_abort(env
->exception
.syndrome
, target_el
,
167 same_el
, fi
->ea
, fi
->s1ptw
,
168 access_type
== MMU_DATA_STORE
,
170 if (access_type
== MMU_DATA_STORE
171 && arm_feature(env
, ARM_FEATURE_V6
)) {
174 exc
= EXCP_DATA_ABORT
;
177 env
->exception
.vaddress
= addr
;
178 env
->exception
.fsr
= fsr
;
179 raise_exception(env
, exc
, syn
, target_el
);
182 /* try to fill the TLB and return an exception if error. If retaddr is
183 * NULL, it means that the function was called in C code (i.e. not
184 * from generated code or from helper.c)
186 void tlb_fill(CPUState
*cs
, target_ulong addr
, int size
,
187 MMUAccessType access_type
, int mmu_idx
, uintptr_t retaddr
)
190 ARMMMUFaultInfo fi
= {};
192 ret
= arm_tlb_fill(cs
, addr
, access_type
, mmu_idx
, &fi
);
194 ARMCPU
*cpu
= ARM_CPU(cs
);
196 /* now we have a real cpu fault */
197 cpu_restore_state(cs
, retaddr
, true);
199 deliver_fault(cpu
, addr
, access_type
, mmu_idx
, &fi
);
203 /* Raise a data fault alignment exception for the specified virtual address */
204 void arm_cpu_do_unaligned_access(CPUState
*cs
, vaddr vaddr
,
205 MMUAccessType access_type
,
206 int mmu_idx
, uintptr_t retaddr
)
208 ARMCPU
*cpu
= ARM_CPU(cs
);
209 ARMMMUFaultInfo fi
= {};
211 /* now we have a real cpu fault */
212 cpu_restore_state(cs
, retaddr
, true);
214 fi
.type
= ARMFault_Alignment
;
215 deliver_fault(cpu
, vaddr
, access_type
, mmu_idx
, &fi
);
218 /* arm_cpu_do_transaction_failed: handle a memory system error response
219 * (eg "no device/memory present at address") by raising an external abort
222 void arm_cpu_do_transaction_failed(CPUState
*cs
, hwaddr physaddr
,
223 vaddr addr
, unsigned size
,
224 MMUAccessType access_type
,
225 int mmu_idx
, MemTxAttrs attrs
,
226 MemTxResult response
, uintptr_t retaddr
)
228 ARMCPU
*cpu
= ARM_CPU(cs
);
229 ARMMMUFaultInfo fi
= {};
231 /* now we have a real cpu fault */
232 cpu_restore_state(cs
, retaddr
, true);
234 fi
.ea
= arm_extabort_type(response
);
235 fi
.type
= ARMFault_SyncExternal
;
236 deliver_fault(cpu
, addr
, access_type
, mmu_idx
, &fi
);
239 #endif /* !defined(CONFIG_USER_ONLY) */
241 void HELPER(v8m_stackcheck
)(CPUARMState
*env
, uint32_t newvalue
)
244 * Perform the v8M stack limit check for SP updates from translated code,
245 * raising an exception if the limit is breached.
247 if (newvalue
< v7m_sp_limit(env
)) {
248 CPUState
*cs
= CPU(arm_env_get_cpu(env
));
251 * Stack limit exceptions are a rare case, so rather than syncing
252 * PC/condbits before the call, we use cpu_restore_state() to
253 * get them right before raising the exception.
255 cpu_restore_state(cs
, GETPC(), true);
256 raise_exception(env
, EXCP_STKOF
, 0, 1);
260 uint32_t HELPER(add_setq
)(CPUARMState
*env
, uint32_t a
, uint32_t b
)
262 uint32_t res
= a
+ b
;
263 if (((res
^ a
) & SIGNBIT
) && !((a
^ b
) & SIGNBIT
))
268 uint32_t HELPER(add_saturate
)(CPUARMState
*env
, uint32_t a
, uint32_t b
)
270 uint32_t res
= a
+ b
;
271 if (((res
^ a
) & SIGNBIT
) && !((a
^ b
) & SIGNBIT
)) {
273 res
= ~(((int32_t)a
>> 31) ^ SIGNBIT
);
278 uint32_t HELPER(sub_saturate
)(CPUARMState
*env
, uint32_t a
, uint32_t b
)
280 uint32_t res
= a
- b
;
281 if (((res
^ a
) & SIGNBIT
) && ((a
^ b
) & SIGNBIT
)) {
283 res
= ~(((int32_t)a
>> 31) ^ SIGNBIT
);
288 uint32_t HELPER(double_saturate
)(CPUARMState
*env
, int32_t val
)
291 if (val
>= 0x40000000) {
294 } else if (val
<= (int32_t)0xc0000000) {
303 uint32_t HELPER(add_usaturate
)(CPUARMState
*env
, uint32_t a
, uint32_t b
)
305 uint32_t res
= a
+ b
;
313 uint32_t HELPER(sub_usaturate
)(CPUARMState
*env
, uint32_t a
, uint32_t b
)
315 uint32_t res
= a
- b
;
323 /* Signed saturation. */
324 static inline uint32_t do_ssat(CPUARMState
*env
, int32_t val
, int shift
)
330 mask
= (1u << shift
) - 1;
334 } else if (top
< -1) {
341 /* Unsigned saturation. */
342 static inline uint32_t do_usat(CPUARMState
*env
, int32_t val
, int shift
)
346 max
= (1u << shift
) - 1;
350 } else if (val
> max
) {
357 /* Signed saturate. */
358 uint32_t HELPER(ssat
)(CPUARMState
*env
, uint32_t x
, uint32_t shift
)
360 return do_ssat(env
, x
, shift
);
363 /* Dual halfword signed saturate. */
364 uint32_t HELPER(ssat16
)(CPUARMState
*env
, uint32_t x
, uint32_t shift
)
368 res
= (uint16_t)do_ssat(env
, (int16_t)x
, shift
);
369 res
|= do_ssat(env
, ((int32_t)x
) >> 16, shift
) << 16;
373 /* Unsigned saturate. */
374 uint32_t HELPER(usat
)(CPUARMState
*env
, uint32_t x
, uint32_t shift
)
376 return do_usat(env
, x
, shift
);
379 /* Dual halfword unsigned saturate. */
380 uint32_t HELPER(usat16
)(CPUARMState
*env
, uint32_t x
, uint32_t shift
)
384 res
= (uint16_t)do_usat(env
, (int16_t)x
, shift
);
385 res
|= do_usat(env
, ((int32_t)x
) >> 16, shift
) << 16;
389 void HELPER(setend
)(CPUARMState
*env
)
391 env
->uncached_cpsr
^= CPSR_E
;
394 /* Function checks whether WFx (WFI/WFE) instructions are set up to be trapped.
395 * The function returns the target EL (1-3) if the instruction is to be trapped;
396 * otherwise it returns 0 indicating it is not trapped.
398 static inline int check_wfx_trap(CPUARMState
*env
, bool is_wfe
)
400 int cur_el
= arm_current_el(env
);
403 if (arm_feature(env
, ARM_FEATURE_M
)) {
404 /* M profile cores can never trap WFI/WFE. */
408 /* If we are currently in EL0 then we need to check if SCTLR is set up for
409 * WFx instructions being trapped to EL1. These trap bits don't exist in v7.
411 if (cur_el
< 1 && arm_feature(env
, ARM_FEATURE_V8
)) {
414 mask
= is_wfe
? SCTLR_nTWE
: SCTLR_nTWI
;
415 if (arm_is_secure_below_el3(env
) && !arm_el_is_aa64(env
, 3)) {
416 /* Secure EL0 and Secure PL1 is at EL3 */
422 if (!(env
->cp15
.sctlr_el
[target_el
] & mask
)) {
427 /* We are not trapping to EL1; trap to EL2 if HCR_EL2 requires it
428 * No need for ARM_FEATURE check as if HCR_EL2 doesn't exist the
429 * bits will be zero indicating no trap.
431 if (cur_el
< 2 && !arm_is_secure(env
)) {
432 mask
= (is_wfe
) ? HCR_TWE
: HCR_TWI
;
433 if (env
->cp15
.hcr_el2
& mask
) {
438 /* We are not trapping to EL1 or EL2; trap to EL3 if SCR_EL3 requires it */
440 mask
= (is_wfe
) ? SCR_TWE
: SCR_TWI
;
441 if (env
->cp15
.scr_el3
& mask
) {
449 void HELPER(wfi
)(CPUARMState
*env
, uint32_t insn_len
)
451 CPUState
*cs
= CPU(arm_env_get_cpu(env
));
452 int target_el
= check_wfx_trap(env
, false);
454 if (cpu_has_work(cs
)) {
455 /* Don't bother to go into our "low power state" if
456 * we would just wake up immediately.
463 raise_exception(env
, EXCP_UDEF
, syn_wfx(1, 0xe, 0, insn_len
== 2),
467 cs
->exception_index
= EXCP_HLT
;
472 void HELPER(wfe
)(CPUARMState
*env
)
474 /* This is a hint instruction that is semantically different
475 * from YIELD even though we currently implement it identically.
476 * Don't actually halt the CPU, just yield back to top
477 * level loop. This is not going into a "low power state"
478 * (ie halting until some event occurs), so we never take
479 * a configurable trap to a different exception level.
484 void HELPER(yield
)(CPUARMState
*env
)
486 ARMCPU
*cpu
= arm_env_get_cpu(env
);
487 CPUState
*cs
= CPU(cpu
);
489 /* This is a non-trappable hint instruction that generally indicates
490 * that the guest is currently busy-looping. Yield control back to the
491 * top level loop so that a more deserving VCPU has a chance to run.
493 cs
->exception_index
= EXCP_YIELD
;
497 /* Raise an internal-to-QEMU exception. This is limited to only
498 * those EXCP values which are special cases for QEMU to interrupt
499 * execution and not to be used for exceptions which are passed to
500 * the guest (those must all have syndrome information and thus should
501 * use exception_with_syndrome).
503 void HELPER(exception_internal
)(CPUARMState
*env
, uint32_t excp
)
505 CPUState
*cs
= CPU(arm_env_get_cpu(env
));
507 assert(excp_is_internal(excp
));
508 cs
->exception_index
= excp
;
512 /* Raise an exception with the specified syndrome register value */
513 void HELPER(exception_with_syndrome
)(CPUARMState
*env
, uint32_t excp
,
514 uint32_t syndrome
, uint32_t target_el
)
516 raise_exception(env
, excp
, syndrome
, target_el
);
519 /* Raise an EXCP_BKPT with the specified syndrome register value,
520 * targeting the correct exception level for debug exceptions.
522 void HELPER(exception_bkpt_insn
)(CPUARMState
*env
, uint32_t syndrome
)
524 /* FSR will only be used if the debug target EL is AArch32. */
525 env
->exception
.fsr
= arm_debug_exception_fsr(env
);
526 /* FAR is UNKNOWN: clear vaddress to avoid potentially exposing
527 * values to the guest that it shouldn't be able to see at its
528 * exception/security level.
530 env
->exception
.vaddress
= 0;
531 raise_exception(env
, EXCP_BKPT
, syndrome
, arm_debug_target_el(env
));
534 uint32_t HELPER(cpsr_read
)(CPUARMState
*env
)
536 return cpsr_read(env
) & ~(CPSR_EXEC
| CPSR_RESERVED
);
539 void HELPER(cpsr_write
)(CPUARMState
*env
, uint32_t val
, uint32_t mask
)
541 cpsr_write(env
, val
, mask
, CPSRWriteByInstr
);
544 /* Write the CPSR for a 32-bit exception return */
545 void HELPER(cpsr_write_eret
)(CPUARMState
*env
, uint32_t val
)
547 qemu_mutex_lock_iothread();
548 arm_call_pre_el_change_hook(arm_env_get_cpu(env
));
549 qemu_mutex_unlock_iothread();
551 cpsr_write(env
, val
, CPSR_ERET_MASK
, CPSRWriteExceptionReturn
);
553 /* Generated code has already stored the new PC value, but
554 * without masking out its low bits, because which bits need
555 * masking depends on whether we're returning to Thumb or ARM
556 * state. Do the masking now.
558 env
->regs
[15] &= (env
->thumb
? ~1 : ~3);
560 qemu_mutex_lock_iothread();
561 arm_call_el_change_hook(arm_env_get_cpu(env
));
562 qemu_mutex_unlock_iothread();
565 /* Access to user mode registers from privileged modes. */
566 uint32_t HELPER(get_user_reg
)(CPUARMState
*env
, uint32_t regno
)
571 val
= env
->banked_r13
[BANK_USRSYS
];
572 } else if (regno
== 14) {
573 val
= env
->banked_r14
[BANK_USRSYS
];
574 } else if (regno
>= 8
575 && (env
->uncached_cpsr
& 0x1f) == ARM_CPU_MODE_FIQ
) {
576 val
= env
->usr_regs
[regno
- 8];
578 val
= env
->regs
[regno
];
583 void HELPER(set_user_reg
)(CPUARMState
*env
, uint32_t regno
, uint32_t val
)
586 env
->banked_r13
[BANK_USRSYS
] = val
;
587 } else if (regno
== 14) {
588 env
->banked_r14
[BANK_USRSYS
] = val
;
589 } else if (regno
>= 8
590 && (env
->uncached_cpsr
& 0x1f) == ARM_CPU_MODE_FIQ
) {
591 env
->usr_regs
[regno
- 8] = val
;
593 env
->regs
[regno
] = val
;
597 void HELPER(set_r13_banked
)(CPUARMState
*env
, uint32_t mode
, uint32_t val
)
599 if ((env
->uncached_cpsr
& CPSR_M
) == mode
) {
602 env
->banked_r13
[bank_number(mode
)] = val
;
606 uint32_t HELPER(get_r13_banked
)(CPUARMState
*env
, uint32_t mode
)
608 if ((env
->uncached_cpsr
& CPSR_M
) == ARM_CPU_MODE_SYS
) {
609 /* SRS instruction is UNPREDICTABLE from System mode; we UNDEF.
610 * Other UNPREDICTABLE and UNDEF cases were caught at translate time.
612 raise_exception(env
, EXCP_UDEF
, syn_uncategorized(),
613 exception_target_el(env
));
616 if ((env
->uncached_cpsr
& CPSR_M
) == mode
) {
617 return env
->regs
[13];
619 return env
->banked_r13
[bank_number(mode
)];
623 static void msr_mrs_banked_exc_checks(CPUARMState
*env
, uint32_t tgtmode
,
626 /* Raise an exception if the requested access is one of the UNPREDICTABLE
627 * cases; otherwise return. This broadly corresponds to the pseudocode
628 * BankedRegisterAccessValid() and SPSRAccessValid(),
629 * except that we have already handled some cases at translate time.
631 int curmode
= env
->uncached_cpsr
& CPSR_M
;
634 /* ELR_Hyp: a special case because access from tgtmode is OK */
635 if (curmode
!= ARM_CPU_MODE_HYP
&& curmode
!= ARM_CPU_MODE_MON
) {
641 if (curmode
== tgtmode
) {
645 if (tgtmode
== ARM_CPU_MODE_USR
) {
648 if (curmode
!= ARM_CPU_MODE_FIQ
) {
653 if (curmode
== ARM_CPU_MODE_SYS
) {
658 if (curmode
== ARM_CPU_MODE_HYP
|| curmode
== ARM_CPU_MODE_SYS
) {
667 if (tgtmode
== ARM_CPU_MODE_HYP
) {
668 /* SPSR_Hyp, r13_hyp: accessible from Monitor mode only */
669 if (curmode
!= ARM_CPU_MODE_MON
) {
677 raise_exception(env
, EXCP_UDEF
, syn_uncategorized(),
678 exception_target_el(env
));
681 void HELPER(msr_banked
)(CPUARMState
*env
, uint32_t value
, uint32_t tgtmode
,
684 msr_mrs_banked_exc_checks(env
, tgtmode
, regno
);
688 env
->banked_spsr
[bank_number(tgtmode
)] = value
;
690 case 17: /* ELR_Hyp */
691 env
->elr_el
[2] = value
;
694 env
->banked_r13
[bank_number(tgtmode
)] = value
;
697 env
->banked_r14
[bank_number(tgtmode
)] = value
;
701 case ARM_CPU_MODE_USR
:
702 env
->usr_regs
[regno
- 8] = value
;
704 case ARM_CPU_MODE_FIQ
:
705 env
->fiq_regs
[regno
- 8] = value
;
708 g_assert_not_reached();
712 g_assert_not_reached();
716 uint32_t HELPER(mrs_banked
)(CPUARMState
*env
, uint32_t tgtmode
, uint32_t regno
)
718 msr_mrs_banked_exc_checks(env
, tgtmode
, regno
);
722 return env
->banked_spsr
[bank_number(tgtmode
)];
723 case 17: /* ELR_Hyp */
724 return env
->elr_el
[2];
726 return env
->banked_r13
[bank_number(tgtmode
)];
728 return env
->banked_r14
[bank_number(tgtmode
)];
731 case ARM_CPU_MODE_USR
:
732 return env
->usr_regs
[regno
- 8];
733 case ARM_CPU_MODE_FIQ
:
734 return env
->fiq_regs
[regno
- 8];
736 g_assert_not_reached();
739 g_assert_not_reached();
743 void HELPER(access_check_cp_reg
)(CPUARMState
*env
, void *rip
, uint32_t syndrome
,
746 const ARMCPRegInfo
*ri
= rip
;
749 if (arm_feature(env
, ARM_FEATURE_XSCALE
) && ri
->cp
< 14
750 && extract32(env
->cp15
.c15_cpar
, ri
->cp
, 1) == 0) {
751 raise_exception(env
, EXCP_UDEF
, syndrome
, exception_target_el(env
));
758 switch (ri
->accessfn(env
, ri
, isread
)) {
762 target_el
= exception_target_el(env
);
764 case CP_ACCESS_TRAP_EL2
:
765 /* Requesting a trap to EL2 when we're in EL3 or S-EL0/1 is
766 * a bug in the access function.
768 assert(!arm_is_secure(env
) && arm_current_el(env
) != 3);
771 case CP_ACCESS_TRAP_EL3
:
774 case CP_ACCESS_TRAP_UNCATEGORIZED
:
775 target_el
= exception_target_el(env
);
776 syndrome
= syn_uncategorized();
778 case CP_ACCESS_TRAP_UNCATEGORIZED_EL2
:
780 syndrome
= syn_uncategorized();
782 case CP_ACCESS_TRAP_UNCATEGORIZED_EL3
:
784 syndrome
= syn_uncategorized();
786 case CP_ACCESS_TRAP_FP_EL2
:
788 /* Since we are an implementation that takes exceptions on a trapped
789 * conditional insn only if the insn has passed its condition code
790 * check, we take the IMPDEF choice to always report CV=1 COND=0xe
791 * (which is also the required value for AArch64 traps).
793 syndrome
= syn_fp_access_trap(1, 0xe, false);
795 case CP_ACCESS_TRAP_FP_EL3
:
797 syndrome
= syn_fp_access_trap(1, 0xe, false);
800 g_assert_not_reached();
803 raise_exception(env
, EXCP_UDEF
, syndrome
, target_el
);
806 void HELPER(set_cp_reg
)(CPUARMState
*env
, void *rip
, uint32_t value
)
808 const ARMCPRegInfo
*ri
= rip
;
810 if (ri
->type
& ARM_CP_IO
) {
811 qemu_mutex_lock_iothread();
812 ri
->writefn(env
, ri
, value
);
813 qemu_mutex_unlock_iothread();
815 ri
->writefn(env
, ri
, value
);
819 uint32_t HELPER(get_cp_reg
)(CPUARMState
*env
, void *rip
)
821 const ARMCPRegInfo
*ri
= rip
;
824 if (ri
->type
& ARM_CP_IO
) {
825 qemu_mutex_lock_iothread();
826 res
= ri
->readfn(env
, ri
);
827 qemu_mutex_unlock_iothread();
829 res
= ri
->readfn(env
, ri
);
835 void HELPER(set_cp_reg64
)(CPUARMState
*env
, void *rip
, uint64_t value
)
837 const ARMCPRegInfo
*ri
= rip
;
839 if (ri
->type
& ARM_CP_IO
) {
840 qemu_mutex_lock_iothread();
841 ri
->writefn(env
, ri
, value
);
842 qemu_mutex_unlock_iothread();
844 ri
->writefn(env
, ri
, value
);
848 uint64_t HELPER(get_cp_reg64
)(CPUARMState
*env
, void *rip
)
850 const ARMCPRegInfo
*ri
= rip
;
853 if (ri
->type
& ARM_CP_IO
) {
854 qemu_mutex_lock_iothread();
855 res
= ri
->readfn(env
, ri
);
856 qemu_mutex_unlock_iothread();
858 res
= ri
->readfn(env
, ri
);
864 void HELPER(msr_i_pstate
)(CPUARMState
*env
, uint32_t op
, uint32_t imm
)
866 /* MSR_i to update PSTATE. This is OK from EL0 only if UMA is set.
867 * Note that SPSel is never OK from EL0; we rely on handle_msr_i()
868 * to catch that case at translate time.
870 if (arm_current_el(env
) == 0 && !(env
->cp15
.sctlr_el
[1] & SCTLR_UMA
)) {
871 uint32_t syndrome
= syn_aa64_sysregtrap(0, extract32(op
, 0, 3),
872 extract32(op
, 3, 3), 4,
874 raise_exception(env
, EXCP_UDEF
, syndrome
, exception_target_el(env
));
878 case 0x05: /* SPSel */
879 update_spsel(env
, imm
);
881 case 0x1e: /* DAIFSet */
882 env
->daif
|= (imm
<< 6) & PSTATE_DAIF
;
884 case 0x1f: /* DAIFClear */
885 env
->daif
&= ~((imm
<< 6) & PSTATE_DAIF
);
888 g_assert_not_reached();
892 void HELPER(clear_pstate_ss
)(CPUARMState
*env
)
894 env
->pstate
&= ~PSTATE_SS
;
897 void HELPER(pre_hvc
)(CPUARMState
*env
)
899 ARMCPU
*cpu
= arm_env_get_cpu(env
);
900 int cur_el
= arm_current_el(env
);
901 /* FIXME: Use actual secure state. */
905 if (arm_is_psci_call(cpu
, EXCP_HVC
)) {
906 /* If PSCI is enabled and this looks like a valid PSCI call then
907 * that overrides the architecturally mandated HVC behaviour.
912 if (!arm_feature(env
, ARM_FEATURE_EL2
)) {
913 /* If EL2 doesn't exist, HVC always UNDEFs */
915 } else if (arm_feature(env
, ARM_FEATURE_EL3
)) {
916 /* EL3.HCE has priority over EL2.HCD. */
917 undef
= !(env
->cp15
.scr_el3
& SCR_HCE
);
919 undef
= env
->cp15
.hcr_el2
& HCR_HCD
;
922 /* In ARMv7 and ARMv8/AArch32, HVC is undef in secure state.
923 * For ARMv8/AArch64, HVC is allowed in EL3.
924 * Note that we've already trapped HVC from EL0 at translation
927 if (secure
&& (!is_a64(env
) || cur_el
== 1)) {
932 raise_exception(env
, EXCP_UDEF
, syn_uncategorized(),
933 exception_target_el(env
));
937 void HELPER(pre_smc
)(CPUARMState
*env
, uint32_t syndrome
)
939 ARMCPU
*cpu
= arm_env_get_cpu(env
);
940 int cur_el
= arm_current_el(env
);
941 bool secure
= arm_is_secure(env
);
942 bool smd
= env
->cp15
.scr_el3
& SCR_SMD
;
943 /* On ARMv8 with EL3 AArch64, SMD applies to both S and NS state.
944 * On ARMv8 with EL3 AArch32, or ARMv7 with the Virtualization
945 * extensions, SMD only applies to NS state.
946 * On ARMv7 without the Virtualization extensions, the SMD bit
947 * doesn't exist, but we forbid the guest to set it to 1 in scr_write(),
948 * so we need not special case this here.
950 bool undef
= arm_feature(env
, ARM_FEATURE_AARCH64
) ? smd
: smd
&& !secure
;
952 if (!arm_feature(env
, ARM_FEATURE_EL3
) &&
953 cpu
->psci_conduit
!= QEMU_PSCI_CONDUIT_SMC
) {
954 /* If we have no EL3 then SMC always UNDEFs and can't be
955 * trapped to EL2. PSCI-via-SMC is a sort of ersatz EL3
956 * firmware within QEMU, and we want an EL2 guest to be able
957 * to forbid its EL1 from making PSCI calls into QEMU's
958 * "firmware" via HCR.TSC, so for these purposes treat
959 * PSCI-via-SMC as implying an EL3.
962 } else if (!secure
&& cur_el
== 1 && (env
->cp15
.hcr_el2
& HCR_TSC
)) {
963 /* In NS EL1, HCR controlled routing to EL2 has priority over SMD.
964 * We also want an EL2 guest to be able to forbid its EL1 from
965 * making PSCI calls into QEMU's "firmware" via HCR.TSC.
967 raise_exception(env
, EXCP_HYP_TRAP
, syndrome
, 2);
970 /* If PSCI is enabled and this looks like a valid PSCI call then
971 * suppress the UNDEF -- we'll catch the SMC exception and
972 * implement the PSCI call behaviour there.
974 if (undef
&& !arm_is_psci_call(cpu
, EXCP_SMC
)) {
975 raise_exception(env
, EXCP_UDEF
, syn_uncategorized(),
976 exception_target_el(env
));
980 static int el_from_spsr(uint32_t spsr
)
982 /* Return the exception level that this SPSR is requesting a return to,
983 * or -1 if it is invalid (an illegal return)
985 if (spsr
& PSTATE_nRW
) {
986 switch (spsr
& CPSR_M
) {
987 case ARM_CPU_MODE_USR
:
989 case ARM_CPU_MODE_HYP
:
991 case ARM_CPU_MODE_FIQ
:
992 case ARM_CPU_MODE_IRQ
:
993 case ARM_CPU_MODE_SVC
:
994 case ARM_CPU_MODE_ABT
:
995 case ARM_CPU_MODE_UND
:
996 case ARM_CPU_MODE_SYS
:
998 case ARM_CPU_MODE_MON
:
999 /* Returning to Mon from AArch64 is never possible,
1000 * so this is an illegal return.
1006 if (extract32(spsr
, 1, 1)) {
1007 /* Return with reserved M[1] bit set */
1010 if (extract32(spsr
, 0, 4) == 1) {
1011 /* return to EL0 with M[0] bit set */
1014 return extract32(spsr
, 2, 2);
1018 void HELPER(exception_return
)(CPUARMState
*env
)
1020 int cur_el
= arm_current_el(env
);
1021 unsigned int spsr_idx
= aarch64_banked_spsr_index(cur_el
);
1022 uint32_t spsr
= env
->banked_spsr
[spsr_idx
];
1024 bool return_to_aa64
= (spsr
& PSTATE_nRW
) == 0;
1026 aarch64_save_sp(env
, cur_el
);
1028 arm_clear_exclusive(env
);
1030 /* We must squash the PSTATE.SS bit to zero unless both of the
1032 * 1. debug exceptions are currently disabled
1033 * 2. singlestep will be active in the EL we return to
1034 * We check 1 here and 2 after we've done the pstate/cpsr write() to
1035 * transition to the EL we're going to.
1037 if (arm_generate_debug_exceptions(env
)) {
1041 new_el
= el_from_spsr(spsr
);
1043 goto illegal_return
;
1046 || (new_el
== 2 && !arm_feature(env
, ARM_FEATURE_EL2
))) {
1047 /* Disallow return to an EL which is unimplemented or higher
1048 * than the current one.
1050 goto illegal_return
;
1053 if (new_el
!= 0 && arm_el_is_aa64(env
, new_el
) != return_to_aa64
) {
1054 /* Return to an EL which is configured for a different register width */
1055 goto illegal_return
;
1058 if (new_el
== 2 && arm_is_secure_below_el3(env
)) {
1059 /* Return to the non-existent secure-EL2 */
1060 goto illegal_return
;
1063 if (new_el
== 1 && (env
->cp15
.hcr_el2
& HCR_TGE
)
1064 && !arm_is_secure_below_el3(env
)) {
1065 goto illegal_return
;
1068 qemu_mutex_lock_iothread();
1069 arm_call_pre_el_change_hook(arm_env_get_cpu(env
));
1070 qemu_mutex_unlock_iothread();
1072 if (!return_to_aa64
) {
1074 /* We do a raw CPSR write because aarch64_sync_64_to_32()
1075 * will sort the register banks out for us, and we've already
1076 * caught all the bad-mode cases in el_from_spsr().
1078 cpsr_write(env
, spsr
, ~0, CPSRWriteRaw
);
1079 if (!arm_singlestep_active(env
)) {
1080 env
->uncached_cpsr
&= ~PSTATE_SS
;
1082 aarch64_sync_64_to_32(env
);
1084 if (spsr
& CPSR_T
) {
1085 env
->regs
[15] = env
->elr_el
[cur_el
] & ~0x1;
1087 env
->regs
[15] = env
->elr_el
[cur_el
] & ~0x3;
1089 qemu_log_mask(CPU_LOG_INT
, "Exception return from AArch64 EL%d to "
1090 "AArch32 EL%d PC 0x%" PRIx32
"\n",
1091 cur_el
, new_el
, env
->regs
[15]);
1094 pstate_write(env
, spsr
);
1095 if (!arm_singlestep_active(env
)) {
1096 env
->pstate
&= ~PSTATE_SS
;
1098 aarch64_restore_sp(env
, new_el
);
1099 env
->pc
= env
->elr_el
[cur_el
];
1100 qemu_log_mask(CPU_LOG_INT
, "Exception return from AArch64 EL%d to "
1101 "AArch64 EL%d PC 0x%" PRIx64
"\n",
1102 cur_el
, new_el
, env
->pc
);
1104 aarch64_sve_change_el(env
, cur_el
, new_el
);
1106 qemu_mutex_lock_iothread();
1107 arm_call_el_change_hook(arm_env_get_cpu(env
));
1108 qemu_mutex_unlock_iothread();
1113 /* Illegal return events of various kinds have architecturally
1114 * mandated behaviour:
1115 * restore NZCV and DAIF from SPSR_ELx
1117 * restore PC from ELR_ELx
1118 * no change to exception level, execution state or stack pointer
1120 env
->pstate
|= PSTATE_IL
;
1121 env
->pc
= env
->elr_el
[cur_el
];
1122 spsr
&= PSTATE_NZCV
| PSTATE_DAIF
;
1123 spsr
|= pstate_read(env
) & ~(PSTATE_NZCV
| PSTATE_DAIF
);
1124 pstate_write(env
, spsr
);
1125 if (!arm_singlestep_active(env
)) {
1126 env
->pstate
&= ~PSTATE_SS
;
1128 qemu_log_mask(LOG_GUEST_ERROR
, "Illegal exception return at EL%d: "
1129 "resuming execution at 0x%" PRIx64
"\n", cur_el
, env
->pc
);
1132 /* Return true if the linked breakpoint entry lbn passes its checks */
1133 static bool linked_bp_matches(ARMCPU
*cpu
, int lbn
)
1135 CPUARMState
*env
= &cpu
->env
;
1136 uint64_t bcr
= env
->cp15
.dbgbcr
[lbn
];
1137 int brps
= extract32(cpu
->dbgdidr
, 24, 4);
1138 int ctx_cmps
= extract32(cpu
->dbgdidr
, 20, 4);
1140 uint32_t contextidr
;
1142 /* Links to unimplemented or non-context aware breakpoints are
1143 * CONSTRAINED UNPREDICTABLE: either behave as if disabled, or
1144 * as if linked to an UNKNOWN context-aware breakpoint (in which
1145 * case DBGWCR<n>_EL1.LBN must indicate that breakpoint).
1146 * We choose the former.
1148 if (lbn
> brps
|| lbn
< (brps
- ctx_cmps
)) {
1152 bcr
= env
->cp15
.dbgbcr
[lbn
];
1154 if (extract64(bcr
, 0, 1) == 0) {
1155 /* Linked breakpoint disabled : generate no events */
1159 bt
= extract64(bcr
, 20, 4);
1161 /* We match the whole register even if this is AArch32 using the
1162 * short descriptor format (in which case it holds both PROCID and ASID),
1163 * since we don't implement the optional v7 context ID masking.
1165 contextidr
= extract64(env
->cp15
.contextidr_el
[1], 0, 32);
1168 case 3: /* linked context ID match */
1169 if (arm_current_el(env
) > 1) {
1170 /* Context matches never fire in EL2 or (AArch64) EL3 */
1173 return (contextidr
== extract64(env
->cp15
.dbgbvr
[lbn
], 0, 32));
1174 case 5: /* linked address mismatch (reserved in AArch64) */
1175 case 9: /* linked VMID match (reserved if no EL2) */
1176 case 11: /* linked context ID and VMID match (reserved if no EL2) */
1178 /* Links to Unlinked context breakpoints must generate no
1179 * events; we choose to do the same for reserved values too.
1187 static bool bp_wp_matches(ARMCPU
*cpu
, int n
, bool is_wp
)
1189 CPUARMState
*env
= &cpu
->env
;
1191 int pac
, hmc
, ssc
, wt
, lbn
;
1192 /* Note that for watchpoints the check is against the CPU security
1193 * state, not the S/NS attribute on the offending data access.
1195 bool is_secure
= arm_is_secure(env
);
1196 int access_el
= arm_current_el(env
);
1199 CPUWatchpoint
*wp
= env
->cpu_watchpoint
[n
];
1201 if (!wp
|| !(wp
->flags
& BP_WATCHPOINT_HIT
)) {
1204 cr
= env
->cp15
.dbgwcr
[n
];
1205 if (wp
->hitattrs
.user
) {
1206 /* The LDRT/STRT/LDT/STT "unprivileged access" instructions should
1207 * match watchpoints as if they were accesses done at EL0, even if
1208 * the CPU is at EL1 or higher.
1213 uint64_t pc
= is_a64(env
) ? env
->pc
: env
->regs
[15];
1215 if (!env
->cpu_breakpoint
[n
] || env
->cpu_breakpoint
[n
]->pc
!= pc
) {
1218 cr
= env
->cp15
.dbgbcr
[n
];
1220 /* The WATCHPOINT_HIT flag guarantees us that the watchpoint is
1221 * enabled and that the address and access type match; for breakpoints
1222 * we know the address matched; check the remaining fields, including
1223 * linked breakpoints. We rely on WCR and BCR having the same layout
1224 * for the LBN, SSC, HMC, PAC/PMC and is-linked fields.
1225 * Note that some combinations of {PAC, HMC, SSC} are reserved and
1226 * must act either like some valid combination or as if the watchpoint
1227 * were disabled. We choose the former, and use this together with
1228 * the fact that EL3 must always be Secure and EL2 must always be
1229 * Non-Secure to simplify the code slightly compared to the full
1230 * table in the ARM ARM.
1232 pac
= extract64(cr
, 1, 2);
1233 hmc
= extract64(cr
, 13, 1);
1234 ssc
= extract64(cr
, 14, 2);
1252 switch (access_el
) {
1260 if (extract32(pac
, 0, 1) == 0) {
1265 if (extract32(pac
, 1, 1) == 0) {
1270 g_assert_not_reached();
1273 wt
= extract64(cr
, 20, 1);
1274 lbn
= extract64(cr
, 16, 4);
1276 if (wt
&& !linked_bp_matches(cpu
, lbn
)) {
1283 static bool check_watchpoints(ARMCPU
*cpu
)
1285 CPUARMState
*env
= &cpu
->env
;
1288 /* If watchpoints are disabled globally or we can't take debug
1289 * exceptions here then watchpoint firings are ignored.
1291 if (extract32(env
->cp15
.mdscr_el1
, 15, 1) == 0
1292 || !arm_generate_debug_exceptions(env
)) {
1296 for (n
= 0; n
< ARRAY_SIZE(env
->cpu_watchpoint
); n
++) {
1297 if (bp_wp_matches(cpu
, n
, true)) {
1304 static bool check_breakpoints(ARMCPU
*cpu
)
1306 CPUARMState
*env
= &cpu
->env
;
1309 /* If breakpoints are disabled globally or we can't take debug
1310 * exceptions here then breakpoint firings are ignored.
1312 if (extract32(env
->cp15
.mdscr_el1
, 15, 1) == 0
1313 || !arm_generate_debug_exceptions(env
)) {
1317 for (n
= 0; n
< ARRAY_SIZE(env
->cpu_breakpoint
); n
++) {
1318 if (bp_wp_matches(cpu
, n
, false)) {
1325 void HELPER(check_breakpoints
)(CPUARMState
*env
)
1327 ARMCPU
*cpu
= arm_env_get_cpu(env
);
1329 if (check_breakpoints(cpu
)) {
1330 HELPER(exception_internal(env
, EXCP_DEBUG
));
1334 bool arm_debug_check_watchpoint(CPUState
*cs
, CPUWatchpoint
*wp
)
1336 /* Called by core code when a CPU watchpoint fires; need to check if this
1337 * is also an architectural watchpoint match.
1339 ARMCPU
*cpu
= ARM_CPU(cs
);
1341 return check_watchpoints(cpu
);
1344 vaddr
arm_adjust_watchpoint_address(CPUState
*cs
, vaddr addr
, int len
)
1346 ARMCPU
*cpu
= ARM_CPU(cs
);
1347 CPUARMState
*env
= &cpu
->env
;
1349 /* In BE32 system mode, target memory is stored byteswapped (on a
1350 * little-endian host system), and by the time we reach here (via an
1351 * opcode helper) the addresses of subword accesses have been adjusted
1352 * to account for that, which means that watchpoints will not match.
1353 * Undo the adjustment here.
1355 if (arm_sctlr_b(env
)) {
1358 } else if (len
== 2) {
1366 void arm_debug_excp_handler(CPUState
*cs
)
1368 /* Called by core code when a watchpoint or breakpoint fires;
1369 * need to check which one and raise the appropriate exception.
1371 ARMCPU
*cpu
= ARM_CPU(cs
);
1372 CPUARMState
*env
= &cpu
->env
;
1373 CPUWatchpoint
*wp_hit
= cs
->watchpoint_hit
;
1376 if (wp_hit
->flags
& BP_CPU
) {
1377 bool wnr
= (wp_hit
->flags
& BP_WATCHPOINT_HIT_WRITE
) != 0;
1378 bool same_el
= arm_debug_target_el(env
) == arm_current_el(env
);
1380 cs
->watchpoint_hit
= NULL
;
1382 env
->exception
.fsr
= arm_debug_exception_fsr(env
);
1383 env
->exception
.vaddress
= wp_hit
->hitaddr
;
1384 raise_exception(env
, EXCP_DATA_ABORT
,
1385 syn_watchpoint(same_el
, 0, wnr
),
1386 arm_debug_target_el(env
));
1389 uint64_t pc
= is_a64(env
) ? env
->pc
: env
->regs
[15];
1390 bool same_el
= (arm_debug_target_el(env
) == arm_current_el(env
));
1392 /* (1) GDB breakpoints should be handled first.
1393 * (2) Do not raise a CPU exception if no CPU breakpoint has fired,
1394 * since singlestep is also done by generating a debug internal
1397 if (cpu_breakpoint_test(cs
, pc
, BP_GDB
)
1398 || !cpu_breakpoint_test(cs
, pc
, BP_CPU
)) {
1402 env
->exception
.fsr
= arm_debug_exception_fsr(env
);
1403 /* FAR is UNKNOWN: clear vaddress to avoid potentially exposing
1404 * values to the guest that it shouldn't be able to see at its
1405 * exception/security level.
1407 env
->exception
.vaddress
= 0;
1408 raise_exception(env
, EXCP_PREFETCH_ABORT
,
1409 syn_breakpoint(same_el
),
1410 arm_debug_target_el(env
));
1414 /* ??? Flag setting arithmetic is awkward because we need to do comparisons.
1415 The only way to do that in TCG is a conditional branch, which clobbers
1416 all our temporaries. For now implement these as helper functions. */
1418 /* Similarly for variable shift instructions. */
1420 uint32_t HELPER(shl_cc
)(CPUARMState
*env
, uint32_t x
, uint32_t i
)
1422 int shift
= i
& 0xff;
1429 } else if (shift
!= 0) {
1430 env
->CF
= (x
>> (32 - shift
)) & 1;
1436 uint32_t HELPER(shr_cc
)(CPUARMState
*env
, uint32_t x
, uint32_t i
)
1438 int shift
= i
& 0xff;
1441 env
->CF
= (x
>> 31) & 1;
1445 } else if (shift
!= 0) {
1446 env
->CF
= (x
>> (shift
- 1)) & 1;
1452 uint32_t HELPER(sar_cc
)(CPUARMState
*env
, uint32_t x
, uint32_t i
)
1454 int shift
= i
& 0xff;
1456 env
->CF
= (x
>> 31) & 1;
1457 return (int32_t)x
>> 31;
1458 } else if (shift
!= 0) {
1459 env
->CF
= (x
>> (shift
- 1)) & 1;
1460 return (int32_t)x
>> shift
;
1465 uint32_t HELPER(ror_cc
)(CPUARMState
*env
, uint32_t x
, uint32_t i
)
1469 shift
= shift1
& 0x1f;
1472 env
->CF
= (x
>> 31) & 1;
1475 env
->CF
= (x
>> (shift
- 1)) & 1;
1476 return ((uint32_t)x
>> shift
) | (x
<< (32 - shift
));