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qemu / qemu / 6720c2b32725e6ac404f22851a0ecd0a71d0cbe2 / . / target / arm / internals.h
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/*
* QEMU ARM CPU -- internal functions and types
*
* Copyright (c) 2014 Linaro Ltd
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see
* <http://www.gnu.org/licenses/gpl-2.0.html>
*
* This header defines functions, types, etc which need to be shared
* between different source files within target/arm/ but which are
* private to it and not required by the rest of QEMU.
*/
#ifndef TARGET_ARM_INTERNALS_H
#define TARGET_ARM_INTERNALS_H
#include "hw/registerfields.h"
#include "tcg/tcg-gvec-desc.h"
#include "syndrome.h"
/* register banks for CPU modes */
#define BANK_USRSYS 0
#define BANK_SVC 1
#define BANK_ABT 2
#define BANK_UND 3
#define BANK_IRQ 4
#define BANK_FIQ 5
#define BANK_HYP 6
#define BANK_MON 7
static inline bool excp_is_internal(int excp)
{
/* Return true if this exception number represents a QEMU-internal
* exception that will not be passed to the guest.
*/
return excp == EXCP_INTERRUPT
|| excp == EXCP_HLT
|| excp == EXCP_DEBUG
|| excp == EXCP_HALTED
|| excp == EXCP_EXCEPTION_EXIT
|| excp == EXCP_KERNEL_TRAP
|| excp == EXCP_SEMIHOST;
}
/* Scale factor for generic timers, ie number of ns per tick.
* This gives a 62.5MHz timer.
*/
#define GTIMER_SCALE 16
/* Bit definitions for the v7M CONTROL register */
FIELD(V7M_CONTROL, NPRIV, 0, 1)
FIELD(V7M_CONTROL, SPSEL, 1, 1)
FIELD(V7M_CONTROL, FPCA, 2, 1)
FIELD(V7M_CONTROL, SFPA, 3, 1)
/* Bit definitions for v7M exception return payload */
FIELD(V7M_EXCRET, ES, 0, 1)
FIELD(V7M_EXCRET, RES0, 1, 1)
FIELD(V7M_EXCRET, SPSEL, 2, 1)
FIELD(V7M_EXCRET, MODE, 3, 1)
FIELD(V7M_EXCRET, FTYPE, 4, 1)
FIELD(V7M_EXCRET, DCRS, 5, 1)
FIELD(V7M_EXCRET, S, 6, 1)
FIELD(V7M_EXCRET, RES1, 7, 25) /* including the must-be-1 prefix */
/* Minimum value which is a magic number for exception return */
#define EXC_RETURN_MIN_MAGIC 0xff000000
/* Minimum number which is a magic number for function or exception return
* when using v8M security extension
*/
#define FNC_RETURN_MIN_MAGIC 0xfefffffe
/* Bit definitions for DBGWCRn and DBGWCRn_EL1 */
FIELD(DBGWCR, E, 0, 1)
FIELD(DBGWCR, PAC, 1, 2)
FIELD(DBGWCR, LSC, 3, 2)
FIELD(DBGWCR, BAS, 5, 8)
FIELD(DBGWCR, HMC, 13, 1)
FIELD(DBGWCR, SSC, 14, 2)
FIELD(DBGWCR, LBN, 16, 4)
FIELD(DBGWCR, WT, 20, 1)
FIELD(DBGWCR, MASK, 24, 5)
FIELD(DBGWCR, SSCE, 29, 1)
/* We use a few fake FSR values for internal purposes in M profile.
* M profile cores don't have A/R format FSRs, but currently our
* get_phys_addr() code assumes A/R profile and reports failures via
* an A/R format FSR value. We then translate that into the proper
* M profile exception and FSR status bit in arm_v7m_cpu_do_interrupt().
* Mostly the FSR values we use for this are those defined for v7PMSA,
* since we share some of that codepath. A few kinds of fault are
* only for M profile and have no A/R equivalent, though, so we have
* to pick a value from the reserved range (which we never otherwise
* generate) to use for these.
* These values will never be visible to the guest.
*/
#define M_FAKE_FSR_NSC_EXEC 0xf /* NS executing in S&NSC memory */
#define M_FAKE_FSR_SFAULT 0xe /* SecureFault INVTRAN, INVEP or AUVIOL */
/**
* raise_exception: Raise the specified exception.
* Raise a guest exception with the specified value, syndrome register
* and target exception level. This should be called from helper functions,
* and never returns because we will longjump back up to the CPU main loop.
*/
G_NORETURN void raise_exception(CPUARMState *env, uint32_t excp,
uint32_t syndrome, uint32_t target_el);
/*
* Similarly, but also use unwinding to restore cpu state.
*/
G_NORETURN void raise_exception_ra(CPUARMState *env, uint32_t excp,
uint32_t syndrome, uint32_t target_el,
uintptr_t ra);
/*
* For AArch64, map a given EL to an index in the banked_spsr array.
* Note that this mapping and the AArch32 mapping defined in bank_number()
* must agree such that the AArch64<->AArch32 SPSRs have the architecturally
* mandated mapping between each other.
*/
static inline unsigned int aarch64_banked_spsr_index(unsigned int el)
{
static const unsigned int map[4] = {
[1] = BANK_SVC, /* EL1. */
[2] = BANK_HYP, /* EL2. */
[3] = BANK_MON, /* EL3. */
};
assert(el >= 1 && el <= 3);
return map[el];
}
/* Map CPU modes onto saved register banks. */
static inline int bank_number(int mode)
{
switch (mode) {
case ARM_CPU_MODE_USR:
case ARM_CPU_MODE_SYS:
return BANK_USRSYS;
case ARM_CPU_MODE_SVC:
return BANK_SVC;
case ARM_CPU_MODE_ABT:
return BANK_ABT;
case ARM_CPU_MODE_UND:
return BANK_UND;
case ARM_CPU_MODE_IRQ:
return BANK_IRQ;
case ARM_CPU_MODE_FIQ:
return BANK_FIQ;
case ARM_CPU_MODE_HYP:
return BANK_HYP;
case ARM_CPU_MODE_MON:
return BANK_MON;
}
g_assert_not_reached();
}
/**
* r14_bank_number: Map CPU mode onto register bank for r14
*
* Given an AArch32 CPU mode, return the index into the saved register
* banks to use for the R14 (LR) in that mode. This is the same as
* bank_number(), except for the special case of Hyp mode, where
* R14 is shared with USR and SYS, unlike its R13 and SPSR.
* This should be used as the index into env->banked_r14[], and
* bank_number() used for the index into env->banked_r13[] and
* env->banked_spsr[].
*/
static inline int r14_bank_number(int mode)
{
return (mode == ARM_CPU_MODE_HYP) ? BANK_USRSYS : bank_number(mode);
}
void arm_cpu_register_gdb_regs_for_features(ARMCPU *cpu);
void arm_translate_init(void);
void arm_restore_state_to_opc(CPUState *cs,
const TranslationBlock *tb,
const uint64_t *data);
#ifdef CONFIG_TCG
void arm_cpu_synchronize_from_tb(CPUState *cs, const TranslationBlock *tb);
#endif /* CONFIG_TCG */
enum arm_fprounding {
FPROUNDING_TIEEVEN,
FPROUNDING_POSINF,
FPROUNDING_NEGINF,
FPROUNDING_ZERO,
FPROUNDING_TIEAWAY,
FPROUNDING_ODD
};
int arm_rmode_to_sf(int rmode);
static inline void aarch64_save_sp(CPUARMState *env, int el)
{
if (env->pstate & PSTATE_SP) {
env->sp_el[el] = env->xregs[31];
} else {
env->sp_el[0] = env->xregs[31];
}
}
static inline void aarch64_restore_sp(CPUARMState *env, int el)
{
if (env->pstate & PSTATE_SP) {
env->xregs[31] = env->sp_el[el];
} else {
env->xregs[31] = env->sp_el[0];
}
}
static inline void update_spsel(CPUARMState *env, uint32_t imm)
{
unsigned int cur_el = arm_current_el(env);
/* Update PSTATE SPSel bit; this requires us to update the
* working stack pointer in xregs[31].
*/
if (!((imm ^ env->pstate) & PSTATE_SP)) {
return;
}
aarch64_save_sp(env, cur_el);
env->pstate = deposit32(env->pstate, 0, 1, imm);
/* We rely on illegal updates to SPsel from EL0 to get trapped
* at translation time.
*/
assert(cur_el >= 1 && cur_el <= 3);
aarch64_restore_sp(env, cur_el);
}
/*
* arm_pamax
* @cpu: ARMCPU
*
* Returns the implementation defined bit-width of physical addresses.
* The ARMv8 reference manuals refer to this as PAMax().
*/
unsigned int arm_pamax(ARMCPU *cpu);
/* Return true if extended addresses are enabled.
* This is always the case if our translation regime is 64 bit,
* but depends on TTBCR.EAE for 32 bit.
*/
static inline bool extended_addresses_enabled(CPUARMState *env)
{
uint64_t tcr = env->cp15.tcr_el[arm_is_secure(env) ? 3 : 1];
if (arm_feature(env, ARM_FEATURE_PMSA) &&
arm_feature(env, ARM_FEATURE_V8)) {
return true;
}
return arm_el_is_aa64(env, 1) ||
(arm_feature(env, ARM_FEATURE_LPAE) && (tcr & TTBCR_EAE));
}
/* Update a QEMU watchpoint based on the information the guest has set in the
* DBGWCR<n>_EL1 and DBGWVR<n>_EL1 registers.
*/
void hw_watchpoint_update(ARMCPU *cpu, int n);
/* Update the QEMU watchpoints for every guest watchpoint. This does a
* complete delete-and-reinstate of the QEMU watchpoint list and so is
* suitable for use after migration or on reset.
*/
void hw_watchpoint_update_all(ARMCPU *cpu);
/* Update a QEMU breakpoint based on the information the guest has set in the
* DBGBCR<n>_EL1 and DBGBVR<n>_EL1 registers.
*/
void hw_breakpoint_update(ARMCPU *cpu, int n);
/* Update the QEMU breakpoints for every guest breakpoint. This does a
* complete delete-and-reinstate of the QEMU breakpoint list and so is
* suitable for use after migration or on reset.
*/
void hw_breakpoint_update_all(ARMCPU *cpu);
/* Callback function for checking if a breakpoint should trigger. */
bool arm_debug_check_breakpoint(CPUState *cs);
/* Callback function for checking if a watchpoint should trigger. */
bool arm_debug_check_watchpoint(CPUState *cs, CPUWatchpoint *wp);
/* Adjust addresses (in BE32 mode) before testing against watchpoint
* addresses.
*/
vaddr arm_adjust_watchpoint_address(CPUState *cs, vaddr addr, int len);
/* Callback function for when a watchpoint or breakpoint triggers. */
void arm_debug_excp_handler(CPUState *cs);
#if defined(CONFIG_USER_ONLY) || !defined(CONFIG_TCG)
static inline bool arm_is_psci_call(ARMCPU *cpu, int excp_type)
{
return false;
}
static inline void arm_handle_psci_call(ARMCPU *cpu)
{
g_assert_not_reached();
}
#else
/* Return true if the r0/x0 value indicates that this SMC/HVC is a PSCI call. */
bool arm_is_psci_call(ARMCPU *cpu, int excp_type);
/* Actually handle a PSCI call */
void arm_handle_psci_call(ARMCPU *cpu);
#endif
/**
* arm_clear_exclusive: clear the exclusive monitor
* @env: CPU env
* Clear the CPU's exclusive monitor, like the guest CLREX instruction.
*/
static inline void arm_clear_exclusive(CPUARMState *env)
{
env->exclusive_addr = -1;
}
/**
* ARMFaultType: type of an ARM MMU fault
* This corresponds to the v8A pseudocode's Fault enumeration,
* with extensions for QEMU internal conditions.
*/
typedef enum ARMFaultType {
ARMFault_None,
ARMFault_AccessFlag,
ARMFault_Alignment,
ARMFault_Background,
ARMFault_Domain,
ARMFault_Permission,
ARMFault_Translation,
ARMFault_AddressSize,
ARMFault_SyncExternal,
ARMFault_SyncExternalOnWalk,
ARMFault_SyncParity,
ARMFault_SyncParityOnWalk,
ARMFault_AsyncParity,
ARMFault_AsyncExternal,
ARMFault_Debug,
ARMFault_TLBConflict,
ARMFault_UnsuppAtomicUpdate,
ARMFault_Lockdown,
ARMFault_Exclusive,
ARMFault_ICacheMaint,
ARMFault_QEMU_NSCExec, /* v8M: NS executing in S&NSC memory */
ARMFault_QEMU_SFault, /* v8M: SecureFault INVTRAN, INVEP or AUVIOL */
} ARMFaultType;
/**
* ARMMMUFaultInfo: Information describing an ARM MMU Fault
* @type: Type of fault
* @level: Table walk level (for translation, access flag and permission faults)
* @domain: Domain of the fault address (for non-LPAE CPUs only)
* @s2addr: Address that caused a fault at stage 2
* @stage2: True if we faulted at stage 2
* @s1ptw: True if we faulted at stage 2 while doing a stage 1 page-table walk
* @s1ns: True if we faulted on a non-secure IPA while in secure state
* @ea: True if we should set the EA (external abort type) bit in syndrome
*/
typedef struct ARMMMUFaultInfo ARMMMUFaultInfo;
struct ARMMMUFaultInfo {
ARMFaultType type;
target_ulong s2addr;
int level;
int domain;
bool stage2;
bool s1ptw;
bool s1ns;
bool ea;
};
/**
* arm_fi_to_sfsc: Convert fault info struct to short-format FSC
* Compare pseudocode EncodeSDFSC(), though unlike that function
* we set up a whole FSR-format code including domain field and
* putting the high bit of the FSC into bit 10.
*/
static inline uint32_t arm_fi_to_sfsc(ARMMMUFaultInfo *fi)
{
uint32_t fsc;
switch (fi->type) {
case ARMFault_None:
return 0;
case ARMFault_AccessFlag:
fsc = fi->level == 1 ? 0x3 : 0x6;
break;
case ARMFault_Alignment:
fsc = 0x1;
break;
case ARMFault_Permission:
fsc = fi->level == 1 ? 0xd : 0xf;
break;
case ARMFault_Domain:
fsc = fi->level == 1 ? 0x9 : 0xb;
break;
case ARMFault_Translation:
fsc = fi->level == 1 ? 0x5 : 0x7;
break;
case ARMFault_SyncExternal:
fsc = 0x8 | (fi->ea << 12);
break;
case ARMFault_SyncExternalOnWalk:
fsc = fi->level == 1 ? 0xc : 0xe;
fsc |= (fi->ea << 12);
break;
case ARMFault_SyncParity:
fsc = 0x409;
break;
case ARMFault_SyncParityOnWalk:
fsc = fi->level == 1 ? 0x40c : 0x40e;
break;
case ARMFault_AsyncParity:
fsc = 0x408;
break;
case ARMFault_AsyncExternal:
fsc = 0x406 | (fi->ea << 12);
break;
case ARMFault_Debug:
fsc = 0x2;
break;
case ARMFault_TLBConflict:
fsc = 0x400;
break;
case ARMFault_Lockdown:
fsc = 0x404;
break;
case ARMFault_Exclusive:
fsc = 0x405;
break;
case ARMFault_ICacheMaint:
fsc = 0x4;
break;
case ARMFault_Background:
fsc = 0x0;
break;
case ARMFault_QEMU_NSCExec:
fsc = M_FAKE_FSR_NSC_EXEC;
break;
case ARMFault_QEMU_SFault:
fsc = M_FAKE_FSR_SFAULT;
break;
default:
/* Other faults can't occur in a context that requires a
* short-format status code.
*/
g_assert_not_reached();
}
fsc |= (fi->domain << 4);
return fsc;
}
/**
* arm_fi_to_lfsc: Convert fault info struct to long-format FSC
* Compare pseudocode EncodeLDFSC(), though unlike that function
* we fill in also the LPAE bit 9 of a DFSR format.
*/
static inline uint32_t arm_fi_to_lfsc(ARMMMUFaultInfo *fi)
{
uint32_t fsc;
switch (fi->type) {
case ARMFault_None:
return 0;
case ARMFault_AddressSize:
assert(fi->level >= -1 && fi->level <= 3);
if (fi->level < 0) {
fsc = 0b101001;
} else {
fsc = fi->level;
}
break;
case ARMFault_AccessFlag:
assert(fi->level >= 0 && fi->level <= 3);
fsc = 0b001000 | fi->level;
break;
case ARMFault_Permission:
assert(fi->level >= 0 && fi->level <= 3);
fsc = 0b001100 | fi->level;
break;
case ARMFault_Translation:
assert(fi->level >= -1 && fi->level <= 3);
if (fi->level < 0) {
fsc = 0b101011;
} else {
fsc = 0b000100 | fi->level;
}
break;
case ARMFault_SyncExternal:
fsc = 0x10 | (fi->ea << 12);
break;
case ARMFault_SyncExternalOnWalk:
assert(fi->level >= -1 && fi->level <= 3);
if (fi->level < 0) {
fsc = 0b010011;
} else {
fsc = 0b010100 | fi->level;
}
fsc |= fi->ea << 12;
break;
case ARMFault_SyncParity:
fsc = 0x18;
break;
case ARMFault_SyncParityOnWalk:
assert(fi->level >= -1 && fi->level <= 3);
if (fi->level < 0) {
fsc = 0b011011;
} else {
fsc = 0b011100 | fi->level;
}
break;
case ARMFault_AsyncParity:
fsc = 0x19;
break;
case ARMFault_AsyncExternal:
fsc = 0x11 | (fi->ea << 12);
break;
case ARMFault_Alignment:
fsc = 0x21;
break;
case ARMFault_Debug:
fsc = 0x22;
break;
case ARMFault_TLBConflict:
fsc = 0x30;
break;
case ARMFault_UnsuppAtomicUpdate:
fsc = 0x31;
break;
case ARMFault_Lockdown:
fsc = 0x34;
break;
case ARMFault_Exclusive:
fsc = 0x35;
break;
default:
/* Other faults can't occur in a context that requires a
* long-format status code.
*/
g_assert_not_reached();
}
fsc |= 1 << 9;
return fsc;
}
static inline bool arm_extabort_type(MemTxResult result)
{
/* The EA bit in syndromes and fault status registers is an
* IMPDEF classification of external aborts. ARM implementations
* usually use this to indicate AXI bus Decode error (0) or
* Slave error (1); in QEMU we follow that.
*/
return result != MEMTX_DECODE_ERROR;
}
#ifdef CONFIG_USER_ONLY
void arm_cpu_record_sigsegv(CPUState *cpu, vaddr addr,
MMUAccessType access_type,
bool maperr, uintptr_t ra);
void arm_cpu_record_sigbus(CPUState *cpu, vaddr addr,
MMUAccessType access_type, uintptr_t ra);
#else
bool arm_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
MMUAccessType access_type, int mmu_idx,
bool probe, uintptr_t retaddr);
#endif
static inline int arm_to_core_mmu_idx(ARMMMUIdx mmu_idx)
{
return mmu_idx & ARM_MMU_IDX_COREIDX_MASK;
}
static inline ARMMMUIdx core_to_arm_mmu_idx(CPUARMState *env, int mmu_idx)
{
if (arm_feature(env, ARM_FEATURE_M)) {
return mmu_idx | ARM_MMU_IDX_M;
} else {
return mmu_idx | ARM_MMU_IDX_A;
}
}
static inline ARMMMUIdx core_to_aa64_mmu_idx(int mmu_idx)
{
/* AArch64 is always a-profile. */
return mmu_idx | ARM_MMU_IDX_A;
}
int arm_mmu_idx_to_el(ARMMMUIdx mmu_idx);
/*
* Return the MMU index for a v7M CPU with all relevant information
* manually specified.
*/
ARMMMUIdx arm_v7m_mmu_idx_all(CPUARMState *env,
bool secstate, bool priv, bool negpri);
/*
* Return the MMU index for a v7M CPU in the specified security and
* privilege state.
*/
ARMMMUIdx arm_v7m_mmu_idx_for_secstate_and_priv(CPUARMState *env,
bool secstate, bool priv);
/* Return the MMU index for a v7M CPU in the specified security state */
ARMMMUIdx arm_v7m_mmu_idx_for_secstate(CPUARMState *env, bool secstate);
/* Return true if the translation regime is using LPAE format page tables */
bool regime_using_lpae_format(CPUARMState *env, ARMMMUIdx mmu_idx);
/*
* Return true if the stage 1 translation regime is using LPAE
* format page tables
*/
bool arm_s1_regime_using_lpae_format(CPUARMState *env, ARMMMUIdx mmu_idx);
/* Raise a data fault alignment exception for the specified virtual address */
G_NORETURN void arm_cpu_do_unaligned_access(CPUState *cs, vaddr vaddr,
MMUAccessType access_type,
int mmu_idx, uintptr_t retaddr);
/* arm_cpu_do_transaction_failed: handle a memory system error response
* (eg "no device/memory present at address") by raising an external abort
* exception
*/
void arm_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
vaddr addr, unsigned size,
MMUAccessType access_type,
int mmu_idx, MemTxAttrs attrs,
MemTxResult response, uintptr_t retaddr);
/* Call any registered EL change hooks */
static inline void arm_call_pre_el_change_hook(ARMCPU *cpu)
{
ARMELChangeHook *hook, *next;
QLIST_FOREACH_SAFE(hook, &cpu->pre_el_change_hooks, node, next) {
hook->hook(cpu, hook->opaque);
}
}
static inline void arm_call_el_change_hook(ARMCPU *cpu)
{
ARMELChangeHook *hook, *next;
QLIST_FOREACH_SAFE(hook, &cpu->el_change_hooks, node, next) {
hook->hook(cpu, hook->opaque);
}
}
/* Return true if this address translation regime has two ranges. */
static inline bool regime_has_2_ranges(ARMMMUIdx mmu_idx)
{
switch (mmu_idx) {
case ARMMMUIdx_Stage1_E0:
case ARMMMUIdx_Stage1_E1:
case ARMMMUIdx_Stage1_E1_PAN:
case ARMMMUIdx_E10_0:
case ARMMMUIdx_E10_1:
case ARMMMUIdx_E10_1_PAN:
case ARMMMUIdx_E20_0:
case ARMMMUIdx_E20_2:
case ARMMMUIdx_E20_2_PAN:
return true;
default:
return false;
}
}
static inline bool regime_is_pan(CPUARMState *env, ARMMMUIdx mmu_idx)
{
switch (mmu_idx) {
case ARMMMUIdx_Stage1_E1_PAN:
case ARMMMUIdx_E10_1_PAN:
case ARMMMUIdx_E20_2_PAN:
return true;
default:
return false;
}
}
static inline bool regime_is_stage2(ARMMMUIdx mmu_idx)
{
return mmu_idx == ARMMMUIdx_Stage2 || mmu_idx == ARMMMUIdx_Stage2_S;
}
/* Return the exception level which controls this address translation regime */
static inline uint32_t regime_el(CPUARMState *env, ARMMMUIdx mmu_idx)
{
switch (mmu_idx) {
case ARMMMUIdx_E20_0:
case ARMMMUIdx_E20_2:
case ARMMMUIdx_E20_2_PAN:
case ARMMMUIdx_Stage2:
case ARMMMUIdx_Stage2_S:
case ARMMMUIdx_E2:
return 2;
case ARMMMUIdx_E3:
return 3;
case ARMMMUIdx_E10_0:
case ARMMMUIdx_Stage1_E0:
return arm_el_is_aa64(env, 3) || !arm_is_secure_below_el3(env) ? 1 : 3;
case ARMMMUIdx_Stage1_E1:
case ARMMMUIdx_Stage1_E1_PAN:
case ARMMMUIdx_E10_1:
case ARMMMUIdx_E10_1_PAN:
case ARMMMUIdx_MPrivNegPri:
case ARMMMUIdx_MUserNegPri:
case ARMMMUIdx_MPriv:
case ARMMMUIdx_MUser:
case ARMMMUIdx_MSPrivNegPri:
case ARMMMUIdx_MSUserNegPri:
case ARMMMUIdx_MSPriv:
case ARMMMUIdx_MSUser:
return 1;
default:
g_assert_not_reached();
}
}
static inline bool regime_is_user(CPUARMState *env, ARMMMUIdx mmu_idx)
{
switch (mmu_idx) {
case ARMMMUIdx_E20_0:
case ARMMMUIdx_Stage1_E0:
case ARMMMUIdx_MUser:
case ARMMMUIdx_MSUser:
case ARMMMUIdx_MUserNegPri:
case ARMMMUIdx_MSUserNegPri:
return true;
default:
return false;
case ARMMMUIdx_E10_0:
case ARMMMUIdx_E10_1:
case ARMMMUIdx_E10_1_PAN:
g_assert_not_reached();
}
}
/* Return the SCTLR value which controls this address translation regime */
static inline uint64_t regime_sctlr(CPUARMState *env, ARMMMUIdx mmu_idx)
{
return env->cp15.sctlr_el[regime_el(env, mmu_idx)];
}
/*
* These are the fields in VTCR_EL2 which affect both the Secure stage 2
* and the Non-Secure stage 2 translation regimes (and hence which are
* not present in VSTCR_EL2).
*/
#define VTCR_SHARED_FIELD_MASK \
(R_VTCR_IRGN0_MASK | R_VTCR_ORGN0_MASK | R_VTCR_SH0_MASK | \
R_VTCR_PS_MASK | R_VTCR_VS_MASK | R_VTCR_HA_MASK | R_VTCR_HD_MASK | \
R_VTCR_DS_MASK)
/* Return the value of the TCR controlling this translation regime */
static inline uint64_t regime_tcr(CPUARMState *env, ARMMMUIdx mmu_idx)
{
if (mmu_idx == ARMMMUIdx_Stage2) {
return env->cp15.vtcr_el2;
}
if (mmu_idx == ARMMMUIdx_Stage2_S) {
/*
* Secure stage 2 shares fields from VTCR_EL2. We merge those
* in with the VSTCR_EL2 value to synthesize a single VTCR_EL2 format
* value so the callers don't need to special case this.
*
* If a future architecture change defines bits in VSTCR_EL2 that
* overlap with these VTCR_EL2 fields we may need to revisit this.
*/
uint64_t v = env->cp15.vstcr_el2 & ~VTCR_SHARED_FIELD_MASK;
v |= env->cp15.vtcr_el2 & VTCR_SHARED_FIELD_MASK;
return v;
}
return env->cp15.tcr_el[regime_el(env, mmu_idx)];
}
/**
* arm_num_brps: Return number of implemented breakpoints.
* Note that the ID register BRPS field is "number of bps - 1",
* and we return the actual number of breakpoints.
*/
static inline int arm_num_brps(ARMCPU *cpu)
{
if (arm_feature(&cpu->env, ARM_FEATURE_AARCH64)) {
return FIELD_EX64(cpu->isar.id_aa64dfr0, ID_AA64DFR0, BRPS) + 1;
} else {
return FIELD_EX32(cpu->isar.dbgdidr, DBGDIDR, BRPS) + 1;
}
}
/**
* arm_num_wrps: Return number of implemented watchpoints.
* Note that the ID register WRPS field is "number of wps - 1",
* and we return the actual number of watchpoints.
*/
static inline int arm_num_wrps(ARMCPU *cpu)
{
if (arm_feature(&cpu->env, ARM_FEATURE_AARCH64)) {
return FIELD_EX64(cpu->isar.id_aa64dfr0, ID_AA64DFR0, WRPS) + 1;
} else {
return FIELD_EX32(cpu->isar.dbgdidr, DBGDIDR, WRPS) + 1;
}
}
/**
* arm_num_ctx_cmps: Return number of implemented context comparators.
* Note that the ID register CTX_CMPS field is "number of cmps - 1",
* and we return the actual number of comparators.
*/
static inline int arm_num_ctx_cmps(ARMCPU *cpu)
{
if (arm_feature(&cpu->env, ARM_FEATURE_AARCH64)) {
return FIELD_EX64(cpu->isar.id_aa64dfr0, ID_AA64DFR0, CTX_CMPS) + 1;
} else {
return FIELD_EX32(cpu->isar.dbgdidr, DBGDIDR, CTX_CMPS) + 1;
}
}
/**
* v7m_using_psp: Return true if using process stack pointer
* Return true if the CPU is currently using the process stack
* pointer, or false if it is using the main stack pointer.
*/
static inline bool v7m_using_psp(CPUARMState *env)
{
/* Handler mode always uses the main stack; for thread mode
* the CONTROL.SPSEL bit determines the answer.
* Note that in v7M it is not possible to be in Handler mode with
* CONTROL.SPSEL non-zero, but in v8M it is, so we must check both.
*/
return !arm_v7m_is_handler_mode(env) &&
env->v7m.control[env->v7m.secure] & R_V7M_CONTROL_SPSEL_MASK;
}
/**
* v7m_sp_limit: Return SP limit for current CPU state
* Return the SP limit value for the current CPU security state
* and stack pointer.
*/
static inline uint32_t v7m_sp_limit(CPUARMState *env)
{
if (v7m_using_psp(env)) {
return env->v7m.psplim[env->v7m.secure];
} else {
return env->v7m.msplim[env->v7m.secure];
}
}
/**
* v7m_cpacr_pass:
* Return true if the v7M CPACR permits access to the FPU for the specified
* security state and privilege level.
*/
static inline bool v7m_cpacr_pass(CPUARMState *env,
bool is_secure, bool is_priv)
{
switch (extract32(env->v7m.cpacr[is_secure], 20, 2)) {
case 0:
case 2: /* UNPREDICTABLE: we treat like 0 */
return false;
case 1:
return is_priv;
case 3:
return true;
default:
g_assert_not_reached();
}
}
/**
* aarch32_mode_name(): Return name of the AArch32 CPU mode
* @psr: Program Status Register indicating CPU mode
*
* Returns, for debug logging purposes, a printable representation
* of the AArch32 CPU mode ("svc", "usr", etc) as indicated by
* the low bits of the specified PSR.
*/
static inline const char *aarch32_mode_name(uint32_t psr)
{
static const char cpu_mode_names[16][4] = {
"usr", "fiq", "irq", "svc", "???", "???", "mon", "abt",
"???", "???", "hyp", "und", "???", "???", "???", "sys"
};
return cpu_mode_names[psr & 0xf];
}
/**
* arm_cpu_update_virq: Update CPU_INTERRUPT_VIRQ bit in cs->interrupt_request
*
* Update the CPU_INTERRUPT_VIRQ bit in cs->interrupt_request, following
* a change to either the input VIRQ line from the GIC or the HCR_EL2.VI bit.
* Must be called with the iothread lock held.
*/
void arm_cpu_update_virq(ARMCPU *cpu);
/**
* arm_cpu_update_vfiq: Update CPU_INTERRUPT_VFIQ bit in cs->interrupt_request
*
* Update the CPU_INTERRUPT_VFIQ bit in cs->interrupt_request, following
* a change to either the input VFIQ line from the GIC or the HCR_EL2.VF bit.
* Must be called with the iothread lock held.
*/
void arm_cpu_update_vfiq(ARMCPU *cpu);
/**
* arm_cpu_update_vserr: Update CPU_INTERRUPT_VSERR bit
*
* Update the CPU_INTERRUPT_VSERR bit in cs->interrupt_request,
* following a change to the HCR_EL2.VSE bit.
*/
void arm_cpu_update_vserr(ARMCPU *cpu);
/**
* arm_mmu_idx_el:
* @env: The cpu environment
* @el: The EL to use.
*
* Return the full ARMMMUIdx for the translation regime for EL.
*/
ARMMMUIdx arm_mmu_idx_el(CPUARMState *env, int el);
/**
* arm_mmu_idx:
* @env: The cpu environment
*
* Return the full ARMMMUIdx for the current translation regime.
*/
ARMMMUIdx arm_mmu_idx(CPUARMState *env);
/**
* arm_stage1_mmu_idx:
* @env: The cpu environment
*
* Return the ARMMMUIdx for the stage1 traversal for the current regime.
*/
#ifdef CONFIG_USER_ONLY
static inline ARMMMUIdx stage_1_mmu_idx(ARMMMUIdx mmu_idx)
{
return ARMMMUIdx_Stage1_E0;
}
static inline ARMMMUIdx arm_stage1_mmu_idx(CPUARMState *env)
{
return ARMMMUIdx_Stage1_E0;
}
#else
ARMMMUIdx stage_1_mmu_idx(ARMMMUIdx mmu_idx);
ARMMMUIdx arm_stage1_mmu_idx(CPUARMState *env);
#endif
/**
* arm_mmu_idx_is_stage1_of_2:
* @mmu_idx: The ARMMMUIdx to test
*
* Return true if @mmu_idx is a NOTLB mmu_idx that is the
* first stage of a two stage regime.
*/
static inline bool arm_mmu_idx_is_stage1_of_2(ARMMMUIdx mmu_idx)
{
switch (mmu_idx) {
case ARMMMUIdx_Stage1_E0:
case ARMMMUIdx_Stage1_E1:
case ARMMMUIdx_Stage1_E1_PAN:
return true;
default:
return false;
}
}
static inline uint32_t aarch32_cpsr_valid_mask(uint64_t features,
const ARMISARegisters *id)
{
uint32_t valid = CPSR_M | CPSR_AIF | CPSR_IL | CPSR_NZCV;
if ((features >> ARM_FEATURE_V4T) & 1) {
valid |= CPSR_T;
}
if ((features >> ARM_FEATURE_V5) & 1) {
valid |= CPSR_Q; /* V5TE in reality*/
}
if ((features >> ARM_FEATURE_V6) & 1) {
valid |= CPSR_E | CPSR_GE;
}
if ((features >> ARM_FEATURE_THUMB2) & 1) {
valid |= CPSR_IT;
}
if (isar_feature_aa32_jazelle(id)) {
valid |= CPSR_J;
}
if (isar_feature_aa32_pan(id)) {
valid |= CPSR_PAN;
}
if (isar_feature_aa32_dit(id)) {
valid |= CPSR_DIT;
}
if (isar_feature_aa32_ssbs(id)) {
valid |= CPSR_SSBS;
}
return valid;
}
static inline uint32_t aarch64_pstate_valid_mask(const ARMISARegisters *id)
{
uint32_t valid;
valid = PSTATE_M | PSTATE_DAIF | PSTATE_IL | PSTATE_SS | PSTATE_NZCV;
if (isar_feature_aa64_bti(id)) {
valid |= PSTATE_BTYPE;
}
if (isar_feature_aa64_pan(id)) {
valid |= PSTATE_PAN;
}
if (isar_feature_aa64_uao(id)) {
valid |= PSTATE_UAO;
}
if (isar_feature_aa64_dit(id)) {
valid |= PSTATE_DIT;
}
if (isar_feature_aa64_ssbs(id)) {
valid |= PSTATE_SSBS;
}
if (isar_feature_aa64_mte(id)) {
valid |= PSTATE_TCO;
}
return valid;
}
/* Granule size (i.e. page size) */
typedef enum ARMGranuleSize {
/* Same order as TG0 encoding */
Gran4K,
Gran64K,
Gran16K,
GranInvalid,
} ARMGranuleSize;
/**
* arm_granule_bits: Return address size of the granule in bits
*
* Return the address size of the granule in bits. This corresponds
* to the pseudocode TGxGranuleBits().
*/
static inline int arm_granule_bits(ARMGranuleSize gran)
{
switch (gran) {
case Gran64K:
return 16;
case Gran16K:
return 14;
case Gran4K:
return 12;
default:
g_assert_not_reached();
}
}
/*
* Parameters of a given virtual address, as extracted from the
* translation control register (TCR) for a given regime.
*/
typedef struct ARMVAParameters {
unsigned tsz : 8;
unsigned ps : 3;
unsigned sh : 2;
unsigned select : 1;
bool tbi : 1;
bool epd : 1;
bool hpd : 1;
bool tsz_oob : 1; /* tsz has been clamped to legal range */
bool ds : 1;
bool ha : 1;
bool hd : 1;
ARMGranuleSize gran : 2;
} ARMVAParameters;
ARMVAParameters aa64_va_parameters(CPUARMState *env, uint64_t va,
ARMMMUIdx mmu_idx, bool data);
int aa64_va_parameter_tbi(uint64_t tcr, ARMMMUIdx mmu_idx);
int aa64_va_parameter_tbid(uint64_t tcr, ARMMMUIdx mmu_idx);
/* Determine if allocation tags are available. */
static inline bool allocation_tag_access_enabled(CPUARMState *env, int el,
uint64_t sctlr)
{
if (el < 3
&& arm_feature(env, ARM_FEATURE_EL3)
&& !(env->cp15.scr_el3 & SCR_ATA)) {
return false;
}
if (el < 2 && arm_is_el2_enabled(env)) {
uint64_t hcr = arm_hcr_el2_eff(env);
if (!(hcr & HCR_ATA) && (!(hcr & HCR_E2H) || !(hcr & HCR_TGE))) {
return false;
}
}
sctlr &= (el == 0 ? SCTLR_ATA0 : SCTLR_ATA);
return sctlr != 0;
}
#ifndef CONFIG_USER_ONLY
/* Security attributes for an address, as returned by v8m_security_lookup. */
typedef struct V8M_SAttributes {
bool subpage; /* true if these attrs don't cover the whole TARGET_PAGE */
bool ns;
bool nsc;
uint8_t sregion;
bool srvalid;
uint8_t iregion;
bool irvalid;
} V8M_SAttributes;
void v8m_security_lookup(CPUARMState *env, uint32_t address,
MMUAccessType access_type, ARMMMUIdx mmu_idx,
bool secure, V8M_SAttributes *sattrs);
/* Cacheability and shareability attributes for a memory access */
typedef struct ARMCacheAttrs {
/*
* If is_s2_format is true, attrs is the S2 descriptor bits [5:2]
* Otherwise, attrs is the same as the MAIR_EL1 8-bit format
*/
unsigned int attrs:8;
unsigned int shareability:2; /* as in the SH field of the VMSAv8-64 PTEs */
bool is_s2_format:1;
bool guarded:1; /* guarded bit of the v8-64 PTE */
} ARMCacheAttrs;
/* Fields that are valid upon success. */
typedef struct GetPhysAddrResult {
CPUTLBEntryFull f;
ARMCacheAttrs cacheattrs;
} GetPhysAddrResult;
/**
* get_phys_addr_with_secure: get the physical address for a virtual address
* @env: CPUARMState
* @address: virtual address to get physical address for
* @access_type: 0 for read, 1 for write, 2 for execute
* @mmu_idx: MMU index indicating required translation regime
* @is_secure: security state for the access
* @result: set on translation success.
* @fi: set to fault info if the translation fails
*
* Find the physical address corresponding to the given virtual address,
* by doing a translation table walk on MMU based systems or using the
* MPU state on MPU based systems.
*
* Returns false if the translation was successful. Otherwise, phys_ptr, attrs,
* prot and page_size may not be filled in, and the populated fsr value provides
* information on why the translation aborted, in the format of a
* DFSR/IFSR fault register, with the following caveats:
* * we honour the short vs long DFSR format differences.
* * the WnR bit is never set (the caller must do this).
* * for PSMAv5 based systems we don't bother to return a full FSR format
* value.
*/
bool get_phys_addr_with_secure(CPUARMState *env, target_ulong address,
MMUAccessType access_type,
ARMMMUIdx mmu_idx, bool is_secure,
GetPhysAddrResult *result, ARMMMUFaultInfo *fi)
__attribute__((nonnull));
/**
* get_phys_addr: get the physical address for a virtual address
* @env: CPUARMState
* @address: virtual address to get physical address for
* @access_type: 0 for read, 1 for write, 2 for execute
* @mmu_idx: MMU index indicating required translation regime
* @result: set on translation success.
* @fi: set to fault info if the translation fails
*
* Similarly, but use the security regime of @mmu_idx.
*/
bool get_phys_addr(CPUARMState *env, target_ulong address,
MMUAccessType access_type, ARMMMUIdx mmu_idx,
GetPhysAddrResult *result, ARMMMUFaultInfo *fi)
__attribute__((nonnull));
bool pmsav8_mpu_lookup(CPUARMState *env, uint32_t address,
MMUAccessType access_type, ARMMMUIdx mmu_idx,
bool is_secure, GetPhysAddrResult *result,
ARMMMUFaultInfo *fi, uint32_t *mregion);
void arm_log_exception(CPUState *cs);
#endif /* !CONFIG_USER_ONLY */
/*
* The log2 of the words in the tag block, for GMID_EL1.BS.
* The is the maximum, 256 bytes, which manipulates 64-bits of tags.
*/
#define GMID_EL1_BS 6
/*
* SVE predicates are 1/8 the size of SVE vectors, and cannot use
* the same simd_desc() encoding due to restrictions on size.
* Use these instead.
*/
FIELD(PREDDESC, OPRSZ, 0, 6)
FIELD(PREDDESC, ESZ, 6, 2)
FIELD(PREDDESC, DATA, 8, 24)
/*
* The SVE simd_data field, for memory ops, contains either
* rd (5 bits) or a shift count (2 bits).
*/
#define SVE_MTEDESC_SHIFT 5
/* Bits within a descriptor passed to the helper_mte_check* functions. */
FIELD(MTEDESC, MIDX, 0, 4)
FIELD(MTEDESC, TBI, 4, 2)
FIELD(MTEDESC, TCMA, 6, 2)
FIELD(MTEDESC, WRITE, 8, 1)
FIELD(MTEDESC, SIZEM1, 9, SIMD_DATA_BITS - 9) /* size - 1 */
bool mte_probe(CPUARMState *env, uint32_t desc, uint64_t ptr);
uint64_t mte_check(CPUARMState *env, uint32_t desc, uint64_t ptr, uintptr_t ra);
static inline int allocation_tag_from_addr(uint64_t ptr)
{
return extract64(ptr, 56, 4);
}
static inline uint64_t address_with_allocation_tag(uint64_t ptr, int rtag)
{
return deposit64(ptr, 56, 4, rtag);
}
/* Return true if tbi bits mean that the access is checked. */
static inline bool tbi_check(uint32_t desc, int bit55)
{
return (desc >> (R_MTEDESC_TBI_SHIFT + bit55)) & 1;
}
/* Return true if tcma bits mean that the access is unchecked. */
static inline bool tcma_check(uint32_t desc, int bit55, int ptr_tag)
{
/*
* We had extracted bit55 and ptr_tag for other reasons, so fold
* (ptr<59:55> == 00000 || ptr<59:55> == 11111) into a single test.
*/
bool match = ((ptr_tag + bit55) & 0xf) == 0;
bool tcma = (desc >> (R_MTEDESC_TCMA_SHIFT + bit55)) & 1;
return tcma && match;
}
/*
* For TBI, ideally, we would do nothing. Proper behaviour on fault is
* for the tag to be present in the FAR_ELx register. But for user-only
* mode, we do not have a TLB with which to implement this, so we must
* remove the top byte.
*/
static inline uint64_t useronly_clean_ptr(uint64_t ptr)
{
#ifdef CONFIG_USER_ONLY
/* TBI0 is known to be enabled, while TBI1 is disabled. */
ptr &= sextract64(ptr, 0, 56);
#endif
return ptr;
}
static inline uint64_t useronly_maybe_clean_ptr(uint32_t desc, uint64_t ptr)
{
#ifdef CONFIG_USER_ONLY
int64_t clean_ptr = sextract64(ptr, 0, 56);
if (tbi_check(desc, clean_ptr < 0)) {
ptr = clean_ptr;
}
#endif
return ptr;
}
/* Values for M-profile PSR.ECI for MVE insns */
enum MVEECIState {
ECI_NONE = 0, /* No completed beats */
ECI_A0 = 1, /* Completed: A0 */
ECI_A0A1 = 2, /* Completed: A0, A1 */
/* 3 is reserved */
ECI_A0A1A2 = 4, /* Completed: A0, A1, A2 */
ECI_A0A1A2B0 = 5, /* Completed: A0, A1, A2, B0 */
/* All other values reserved */
};
/* Definitions for the PMU registers */
#define PMCRN_MASK 0xf800
#define PMCRN_SHIFT 11
#define PMCRLP 0x80
#define PMCRLC 0x40
#define PMCRDP 0x20
#define PMCRX 0x10
#define PMCRD 0x8
#define PMCRC 0x4
#define PMCRP 0x2
#define PMCRE 0x1
/*
* Mask of PMCR bits writable by guest (not including WO bits like C, P,
* which can be written as 1 to trigger behaviour but which stay RAZ).
*/
#define PMCR_WRITABLE_MASK (PMCRLP | PMCRLC | PMCRDP | PMCRX | PMCRD | PMCRE)
#define PMXEVTYPER_P 0x80000000
#define PMXEVTYPER_U 0x40000000
#define PMXEVTYPER_NSK 0x20000000
#define PMXEVTYPER_NSU 0x10000000
#define PMXEVTYPER_NSH 0x08000000
#define PMXEVTYPER_M 0x04000000
#define PMXEVTYPER_MT 0x02000000
#define PMXEVTYPER_EVTCOUNT 0x0000ffff
#define PMXEVTYPER_MASK (PMXEVTYPER_P | PMXEVTYPER_U | PMXEVTYPER_NSK | \
PMXEVTYPER_NSU | PMXEVTYPER_NSH | \
PMXEVTYPER_M | PMXEVTYPER_MT | \
PMXEVTYPER_EVTCOUNT)
#define PMCCFILTR 0xf8000000
#define PMCCFILTR_M PMXEVTYPER_M
#define PMCCFILTR_EL0 (PMCCFILTR | PMCCFILTR_M)
static inline uint32_t pmu_num_counters(CPUARMState *env)
{
ARMCPU *cpu = env_archcpu(env);
return (cpu->isar.reset_pmcr_el0 & PMCRN_MASK) >> PMCRN_SHIFT;
}
/* Bits allowed to be set/cleared for PMCNTEN* and PMINTEN* */
static inline uint64_t pmu_counter_mask(CPUARMState *env)
{
return (1ULL << 31) | ((1ULL << pmu_num_counters(env)) - 1);
}
#ifdef TARGET_AARCH64
int arm_gdb_get_svereg(CPUARMState *env, GByteArray *buf, int reg);
int arm_gdb_set_svereg(CPUARMState *env, uint8_t *buf, int reg);
int aarch64_fpu_gdb_get_reg(CPUARMState *env, GByteArray *buf, int reg);
int aarch64_fpu_gdb_set_reg(CPUARMState *env, uint8_t *buf, int reg);
void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp);
void arm_cpu_sme_finalize(ARMCPU *cpu, Error **errp);
void arm_cpu_pauth_finalize(ARMCPU *cpu, Error **errp);
void arm_cpu_lpa2_finalize(ARMCPU *cpu, Error **errp);
#endif
#ifdef CONFIG_USER_ONLY
static inline void define_cortex_a72_a57_a53_cp_reginfo(ARMCPU *cpu) { }
#else
void define_cortex_a72_a57_a53_cp_reginfo(ARMCPU *cpu);
#endif
bool el_is_in_host(CPUARMState *env, int el);
void aa32_max_features(ARMCPU *cpu);
int exception_target_el(CPUARMState *env);
bool arm_singlestep_active(CPUARMState *env);
bool arm_generate_debug_exceptions(CPUARMState *env);
/* Add the cpreg definitions for debug related system registers */
void define_debug_regs(ARMCPU *cpu);
/* Effective value of MDCR_EL2 */
static inline uint64_t arm_mdcr_el2_eff(CPUARMState *env)
{
return arm_is_el2_enabled(env) ? env->cp15.mdcr_el2 : 0;
}
/* Powers of 2 for sve_vq_map et al. */
#define SVE_VQ_POW2_MAP \
((1 << (1 - 1)) | (1 << (2 - 1)) | \
(1 << (4 - 1)) | (1 << (8 - 1)) | (1 << (16 - 1)))
/*
* Return true if it is possible to take a fine-grained-trap to EL2.
*/
static inline bool arm_fgt_active(CPUARMState *env, int el)
{
/*
* The Arm ARM only requires the "{E2H,TGE} != {1,1}" test for traps
* that can affect EL0, but it is harmless to do the test also for
* traps on registers that are only accessible at EL1 because if the test
* returns true then we can't be executing at EL1 anyway.
* FGT traps only happen when EL2 is enabled and EL1 is AArch64;
* traps from AArch32 only happen for the EL0 is AArch32 case.
*/
return cpu_isar_feature(aa64_fgt, env_archcpu(env)) &&
el < 2 && arm_is_el2_enabled(env) &&
arm_el_is_aa64(env, 1) &&
(arm_hcr_el2_eff(env) & (HCR_E2H | HCR_TGE)) != (HCR_E2H | HCR_TGE) &&
(!arm_feature(env, ARM_FEATURE_EL3) || (env->cp15.scr_el3 & SCR_FGTEN));
}
#endif