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-rw-r--r--target/arm/tcg/op_helper.c1069
1 files changed, 1069 insertions, 0 deletions
diff --git a/target/arm/tcg/op_helper.c b/target/arm/tcg/op_helper.c
new file mode 100644
index 0000000000..3baf8004f6
--- /dev/null
+++ b/target/arm/tcg/op_helper.c
@@ -0,0 +1,1069 @@
+/*
+ *  ARM helper routines
+ *
+ *  Copyright (c) 2005-2007 CodeSourcery, LLC
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+#include "qemu/osdep.h"
+#include "qemu/main-loop.h"
+#include "cpu.h"
+#include "exec/helper-proto.h"
+#include "internals.h"
+#include "exec/exec-all.h"
+#include "exec/cpu_ldst.h"
+#include "cpregs.h"
+
+#define SIGNBIT (uint32_t)0x80000000
+#define SIGNBIT64 ((uint64_t)1 << 63)
+
+int exception_target_el(CPUARMState *env)
+{
+    int target_el = MAX(1, arm_current_el(env));
+
+    /*
+     * No such thing as secure EL1 if EL3 is aarch32,
+     * so update the target EL to EL3 in this case.
+     */
+    if (arm_is_secure(env) && !arm_el_is_aa64(env, 3) && target_el == 1) {
+        target_el = 3;
+    }
+
+    return target_el;
+}
+
+void raise_exception(CPUARMState *env, uint32_t excp,
+                     uint32_t syndrome, uint32_t target_el)
+{
+    CPUState *cs = env_cpu(env);
+
+    if (target_el == 1 && (arm_hcr_el2_eff(env) & HCR_TGE)) {
+        /*
+         * Redirect NS EL1 exceptions to NS EL2. These are reported with
+         * their original syndrome register value, with the exception of
+         * SIMD/FP access traps, which are reported as uncategorized
+         * (see DDI0478C.a D1.10.4)
+         */
+        target_el = 2;
+        if (syn_get_ec(syndrome) == EC_ADVSIMDFPACCESSTRAP) {
+            syndrome = syn_uncategorized();
+        }
+    }
+
+    assert(!excp_is_internal(excp));
+    cs->exception_index = excp;
+    env->exception.syndrome = syndrome;
+    env->exception.target_el = target_el;
+    cpu_loop_exit(cs);
+}
+
+void raise_exception_ra(CPUARMState *env, uint32_t excp, uint32_t syndrome,
+                        uint32_t target_el, uintptr_t ra)
+{
+    CPUState *cs = env_cpu(env);
+
+    /*
+     * restore_state_to_opc() will set env->exception.syndrome, so
+     * we must restore CPU state here before setting the syndrome
+     * the caller passed us, and cannot use cpu_loop_exit_restore().
+     */
+    cpu_restore_state(cs, ra);
+    raise_exception(env, excp, syndrome, target_el);
+}
+
+uint64_t HELPER(neon_tbl)(CPUARMState *env, uint32_t desc,
+                          uint64_t ireg, uint64_t def)
+{
+    uint64_t tmp, val = 0;
+    uint32_t maxindex = ((desc & 3) + 1) * 8;
+    uint32_t base_reg = desc >> 2;
+    uint32_t shift, index, reg;
+
+    for (shift = 0; shift < 64; shift += 8) {
+        index = (ireg >> shift) & 0xff;
+        if (index < maxindex) {
+            reg = base_reg + (index >> 3);
+            tmp = *aa32_vfp_dreg(env, reg);
+            tmp = ((tmp >> ((index & 7) << 3)) & 0xff) << shift;
+        } else {
+            tmp = def & (0xffull << shift);
+        }
+        val |= tmp;
+    }
+    return val;
+}
+
+void HELPER(v8m_stackcheck)(CPUARMState *env, uint32_t newvalue)
+{
+    /*
+     * Perform the v8M stack limit check for SP updates from translated code,
+     * raising an exception if the limit is breached.
+     */
+    if (newvalue < v7m_sp_limit(env)) {
+        /*
+         * Stack limit exceptions are a rare case, so rather than syncing
+         * PC/condbits before the call, we use raise_exception_ra() so
+         * that cpu_restore_state() will sort them out.
+         */
+        raise_exception_ra(env, EXCP_STKOF, 0, 1, GETPC());
+    }
+}
+
+uint32_t HELPER(add_setq)(CPUARMState *env, uint32_t a, uint32_t b)
+{
+    uint32_t res = a + b;
+    if (((res ^ a) & SIGNBIT) && !((a ^ b) & SIGNBIT))
+        env->QF = 1;
+    return res;
+}
+
+uint32_t HELPER(add_saturate)(CPUARMState *env, uint32_t a, uint32_t b)
+{
+    uint32_t res = a + b;
+    if (((res ^ a) & SIGNBIT) && !((a ^ b) & SIGNBIT)) {
+        env->QF = 1;
+        res = ~(((int32_t)a >> 31) ^ SIGNBIT);
+    }
+    return res;
+}
+
+uint32_t HELPER(sub_saturate)(CPUARMState *env, uint32_t a, uint32_t b)
+{
+    uint32_t res = a - b;
+    if (((res ^ a) & SIGNBIT) && ((a ^ b) & SIGNBIT)) {
+        env->QF = 1;
+        res = ~(((int32_t)a >> 31) ^ SIGNBIT);
+    }
+    return res;
+}
+
+uint32_t HELPER(add_usaturate)(CPUARMState *env, uint32_t a, uint32_t b)
+{
+    uint32_t res = a + b;
+    if (res < a) {
+        env->QF = 1;
+        res = ~0;
+    }
+    return res;
+}
+
+uint32_t HELPER(sub_usaturate)(CPUARMState *env, uint32_t a, uint32_t b)
+{
+    uint32_t res = a - b;
+    if (res > a) {
+        env->QF = 1;
+        res = 0;
+    }
+    return res;
+}
+
+/* Signed saturation.  */
+static inline uint32_t do_ssat(CPUARMState *env, int32_t val, int shift)
+{
+    int32_t top;
+    uint32_t mask;
+
+    top = val >> shift;
+    mask = (1u << shift) - 1;
+    if (top > 0) {
+        env->QF = 1;
+        return mask;
+    } else if (top < -1) {
+        env->QF = 1;
+        return ~mask;
+    }
+    return val;
+}
+
+/* Unsigned saturation.  */
+static inline uint32_t do_usat(CPUARMState *env, int32_t val, int shift)
+{
+    uint32_t max;
+
+    max = (1u << shift) - 1;
+    if (val < 0) {
+        env->QF = 1;
+        return 0;
+    } else if (val > max) {
+        env->QF = 1;
+        return max;
+    }
+    return val;
+}
+
+/* Signed saturate.  */
+uint32_t HELPER(ssat)(CPUARMState *env, uint32_t x, uint32_t shift)
+{
+    return do_ssat(env, x, shift);
+}
+
+/* Dual halfword signed saturate.  */
+uint32_t HELPER(ssat16)(CPUARMState *env, uint32_t x, uint32_t shift)
+{
+    uint32_t res;
+
+    res = (uint16_t)do_ssat(env, (int16_t)x, shift);
+    res |= do_ssat(env, ((int32_t)x) >> 16, shift) << 16;
+    return res;
+}
+
+/* Unsigned saturate.  */
+uint32_t HELPER(usat)(CPUARMState *env, uint32_t x, uint32_t shift)
+{
+    return do_usat(env, x, shift);
+}
+
+/* Dual halfword unsigned saturate.  */
+uint32_t HELPER(usat16)(CPUARMState *env, uint32_t x, uint32_t shift)
+{
+    uint32_t res;
+
+    res = (uint16_t)do_usat(env, (int16_t)x, shift);
+    res |= do_usat(env, ((int32_t)x) >> 16, shift) << 16;
+    return res;
+}
+
+void HELPER(setend)(CPUARMState *env)
+{
+    env->uncached_cpsr ^= CPSR_E;
+    arm_rebuild_hflags(env);
+}
+
+void HELPER(check_bxj_trap)(CPUARMState *env, uint32_t rm)
+{
+    /*
+     * Only called if in NS EL0 or EL1 for a BXJ for a v7A CPU;
+     * check if HSTR.TJDBX means we need to trap to EL2.
+     */
+    if (env->cp15.hstr_el2 & HSTR_TJDBX) {
+        /*
+         * We know the condition code check passed, so take the IMPDEF
+         * choice to always report CV=1 COND 0xe
+         */
+        uint32_t syn = syn_bxjtrap(1, 0xe, rm);
+        raise_exception_ra(env, EXCP_HYP_TRAP, syn, 2, GETPC());
+    }
+}
+
+#ifndef CONFIG_USER_ONLY
+/* Function checks whether WFx (WFI/WFE) instructions are set up to be trapped.
+ * The function returns the target EL (1-3) if the instruction is to be trapped;
+ * otherwise it returns 0 indicating it is not trapped.
+ */
+static inline int check_wfx_trap(CPUARMState *env, bool is_wfe)
+{
+    int cur_el = arm_current_el(env);
+    uint64_t mask;
+
+    if (arm_feature(env, ARM_FEATURE_M)) {
+        /* M profile cores can never trap WFI/WFE. */
+        return 0;
+    }
+
+    /* If we are currently in EL0 then we need to check if SCTLR is set up for
+     * WFx instructions being trapped to EL1. These trap bits don't exist in v7.
+     */
+    if (cur_el < 1 && arm_feature(env, ARM_FEATURE_V8)) {
+        int target_el;
+
+        mask = is_wfe ? SCTLR_nTWE : SCTLR_nTWI;
+        if (arm_is_secure_below_el3(env) && !arm_el_is_aa64(env, 3)) {
+            /* Secure EL0 and Secure PL1 is at EL3 */
+            target_el = 3;
+        } else {
+            target_el = 1;
+        }
+
+        if (!(env->cp15.sctlr_el[target_el] & mask)) {
+            return target_el;
+        }
+    }
+
+    /* We are not trapping to EL1; trap to EL2 if HCR_EL2 requires it
+     * No need for ARM_FEATURE check as if HCR_EL2 doesn't exist the
+     * bits will be zero indicating no trap.
+     */
+    if (cur_el < 2) {
+        mask = is_wfe ? HCR_TWE : HCR_TWI;
+        if (arm_hcr_el2_eff(env) & mask) {
+            return 2;
+        }
+    }
+
+    /* We are not trapping to EL1 or EL2; trap to EL3 if SCR_EL3 requires it */
+    if (cur_el < 3) {
+        mask = (is_wfe) ? SCR_TWE : SCR_TWI;
+        if (env->cp15.scr_el3 & mask) {
+            return 3;
+        }
+    }
+
+    return 0;
+}
+#endif
+
+void HELPER(wfi)(CPUARMState *env, uint32_t insn_len)
+{
+#ifdef CONFIG_USER_ONLY
+    /*
+     * WFI in the user-mode emulator is technically permitted but not
+     * something any real-world code would do. AArch64 Linux kernels
+     * trap it via SCTRL_EL1.nTWI and make it an (expensive) NOP;
+     * AArch32 kernels don't trap it so it will delay a bit.
+     * For QEMU, make it NOP here, because trying to raise EXCP_HLT
+     * would trigger an abort.
+     */
+    return;
+#else
+    CPUState *cs = env_cpu(env);
+    int target_el = check_wfx_trap(env, false);
+
+    if (cpu_has_work(cs)) {
+        /* Don't bother to go into our "low power state" if
+         * we would just wake up immediately.
+         */
+        return;
+    }
+
+    if (target_el) {
+        if (env->aarch64) {
+            env->pc -= insn_len;
+        } else {
+            env->regs[15] -= insn_len;
+        }
+
+        raise_exception(env, EXCP_UDEF, syn_wfx(1, 0xe, 0, insn_len == 2),
+                        target_el);
+    }
+
+    cs->exception_index = EXCP_HLT;
+    cs->halted = 1;
+    cpu_loop_exit(cs);
+#endif
+}
+
+void HELPER(wfe)(CPUARMState *env)
+{
+    /* This is a hint instruction that is semantically different
+     * from YIELD even though we currently implement it identically.
+     * Don't actually halt the CPU, just yield back to top
+     * level loop. This is not going into a "low power state"
+     * (ie halting until some event occurs), so we never take
+     * a configurable trap to a different exception level.
+     */
+    HELPER(yield)(env);
+}
+
+void HELPER(yield)(CPUARMState *env)
+{
+    CPUState *cs = env_cpu(env);
+
+    /* This is a non-trappable hint instruction that generally indicates
+     * that the guest is currently busy-looping. Yield control back to the
+     * top level loop so that a more deserving VCPU has a chance to run.
+     */
+    cs->exception_index = EXCP_YIELD;
+    cpu_loop_exit(cs);
+}
+
+/* Raise an internal-to-QEMU exception. This is limited to only
+ * those EXCP values which are special cases for QEMU to interrupt
+ * execution and not to be used for exceptions which are passed to
+ * the guest (those must all have syndrome information and thus should
+ * use exception_with_syndrome*).
+ */
+void HELPER(exception_internal)(CPUARMState *env, uint32_t excp)
+{
+    CPUState *cs = env_cpu(env);
+
+    assert(excp_is_internal(excp));
+    cs->exception_index = excp;
+    cpu_loop_exit(cs);
+}
+
+/* Raise an exception with the specified syndrome register value */
+void HELPER(exception_with_syndrome_el)(CPUARMState *env, uint32_t excp,
+                                        uint32_t syndrome, uint32_t target_el)
+{
+    raise_exception(env, excp, syndrome, target_el);
+}
+
+/*
+ * Raise an exception with the specified syndrome register value
+ * to the default target el.
+ */
+void HELPER(exception_with_syndrome)(CPUARMState *env, uint32_t excp,
+                                     uint32_t syndrome)
+{
+    raise_exception(env, excp, syndrome, exception_target_el(env));
+}
+
+uint32_t HELPER(cpsr_read)(CPUARMState *env)
+{
+    return cpsr_read(env) & ~CPSR_EXEC;
+}
+
+void HELPER(cpsr_write)(CPUARMState *env, uint32_t val, uint32_t mask)
+{
+    cpsr_write(env, val, mask, CPSRWriteByInstr);
+    /* TODO: Not all cpsr bits are relevant to hflags.  */
+    arm_rebuild_hflags(env);
+}
+
+/* Write the CPSR for a 32-bit exception return */
+void HELPER(cpsr_write_eret)(CPUARMState *env, uint32_t val)
+{
+    uint32_t mask;
+
+    qemu_mutex_lock_iothread();
+    arm_call_pre_el_change_hook(env_archcpu(env));
+    qemu_mutex_unlock_iothread();
+
+    mask = aarch32_cpsr_valid_mask(env->features, &env_archcpu(env)->isar);
+    cpsr_write(env, val, mask, CPSRWriteExceptionReturn);
+
+    /* Generated code has already stored the new PC value, but
+     * without masking out its low bits, because which bits need
+     * masking depends on whether we're returning to Thumb or ARM
+     * state. Do the masking now.
+     */
+    env->regs[15] &= (env->thumb ? ~1 : ~3);
+    arm_rebuild_hflags(env);
+
+    qemu_mutex_lock_iothread();
+    arm_call_el_change_hook(env_archcpu(env));
+    qemu_mutex_unlock_iothread();
+}
+
+/* Access to user mode registers from privileged modes.  */
+uint32_t HELPER(get_user_reg)(CPUARMState *env, uint32_t regno)
+{
+    uint32_t val;
+
+    if (regno == 13) {
+        val = env->banked_r13[BANK_USRSYS];
+    } else if (regno == 14) {
+        val = env->banked_r14[BANK_USRSYS];
+    } else if (regno >= 8
+               && (env->uncached_cpsr & 0x1f) == ARM_CPU_MODE_FIQ) {
+        val = env->usr_regs[regno - 8];
+    } else {
+        val = env->regs[regno];
+    }
+    return val;
+}
+
+void HELPER(set_user_reg)(CPUARMState *env, uint32_t regno, uint32_t val)
+{
+    if (regno == 13) {
+        env->banked_r13[BANK_USRSYS] = val;
+    } else if (regno == 14) {
+        env->banked_r14[BANK_USRSYS] = val;
+    } else if (regno >= 8
+               && (env->uncached_cpsr & 0x1f) == ARM_CPU_MODE_FIQ) {
+        env->usr_regs[regno - 8] = val;
+    } else {
+        env->regs[regno] = val;
+    }
+}
+
+void HELPER(set_r13_banked)(CPUARMState *env, uint32_t mode, uint32_t val)
+{
+    if ((env->uncached_cpsr & CPSR_M) == mode) {
+        env->regs[13] = val;
+    } else {
+        env->banked_r13[bank_number(mode)] = val;
+    }
+}
+
+uint32_t HELPER(get_r13_banked)(CPUARMState *env, uint32_t mode)
+{
+    if ((env->uncached_cpsr & CPSR_M) == ARM_CPU_MODE_SYS) {
+        /* SRS instruction is UNPREDICTABLE from System mode; we UNDEF.
+         * Other UNPREDICTABLE and UNDEF cases were caught at translate time.
+         */
+        raise_exception(env, EXCP_UDEF, syn_uncategorized(),
+                        exception_target_el(env));
+    }
+
+    if ((env->uncached_cpsr & CPSR_M) == mode) {
+        return env->regs[13];
+    } else {
+        return env->banked_r13[bank_number(mode)];
+    }
+}
+
+static void msr_mrs_banked_exc_checks(CPUARMState *env, uint32_t tgtmode,
+                                      uint32_t regno)
+{
+    /* Raise an exception if the requested access is one of the UNPREDICTABLE
+     * cases; otherwise return. This broadly corresponds to the pseudocode
+     * BankedRegisterAccessValid() and SPSRAccessValid(),
+     * except that we have already handled some cases at translate time.
+     */
+    int curmode = env->uncached_cpsr & CPSR_M;
+
+    if (regno == 17) {
+        /* ELR_Hyp: a special case because access from tgtmode is OK */
+        if (curmode != ARM_CPU_MODE_HYP && curmode != ARM_CPU_MODE_MON) {
+            goto undef;
+        }
+        return;
+    }
+
+    if (curmode == tgtmode) {
+        goto undef;
+    }
+
+    if (tgtmode == ARM_CPU_MODE_USR) {
+        switch (regno) {
+        case 8 ... 12:
+            if (curmode != ARM_CPU_MODE_FIQ) {
+                goto undef;
+            }
+            break;
+        case 13:
+            if (curmode == ARM_CPU_MODE_SYS) {
+                goto undef;
+            }
+            break;
+        case 14:
+            if (curmode == ARM_CPU_MODE_HYP || curmode == ARM_CPU_MODE_SYS) {
+                goto undef;
+            }
+            break;
+        default:
+            break;
+        }
+    }
+
+    if (tgtmode == ARM_CPU_MODE_HYP) {
+        /* SPSR_Hyp, r13_hyp: accessible from Monitor mode only */
+        if (curmode != ARM_CPU_MODE_MON) {
+            goto undef;
+        }
+    }
+
+    return;
+
+undef:
+    raise_exception(env, EXCP_UDEF, syn_uncategorized(),
+                    exception_target_el(env));
+}
+
+void HELPER(msr_banked)(CPUARMState *env, uint32_t value, uint32_t tgtmode,
+                        uint32_t regno)
+{
+    msr_mrs_banked_exc_checks(env, tgtmode, regno);
+
+    switch (regno) {
+    case 16: /* SPSRs */
+        env->banked_spsr[bank_number(tgtmode)] = value;
+        break;
+    case 17: /* ELR_Hyp */
+        env->elr_el[2] = value;
+        break;
+    case 13:
+        env->banked_r13[bank_number(tgtmode)] = value;
+        break;
+    case 14:
+        env->banked_r14[r14_bank_number(tgtmode)] = value;
+        break;
+    case 8 ... 12:
+        switch (tgtmode) {
+        case ARM_CPU_MODE_USR:
+            env->usr_regs[regno - 8] = value;
+            break;
+        case ARM_CPU_MODE_FIQ:
+            env->fiq_regs[regno - 8] = value;
+            break;
+        default:
+            g_assert_not_reached();
+        }
+        break;
+    default:
+        g_assert_not_reached();
+    }
+}
+
+uint32_t HELPER(mrs_banked)(CPUARMState *env, uint32_t tgtmode, uint32_t regno)
+{
+    msr_mrs_banked_exc_checks(env, tgtmode, regno);
+
+    switch (regno) {
+    case 16: /* SPSRs */
+        return env->banked_spsr[bank_number(tgtmode)];
+    case 17: /* ELR_Hyp */
+        return env->elr_el[2];
+    case 13:
+        return env->banked_r13[bank_number(tgtmode)];
+    case 14:
+        return env->banked_r14[r14_bank_number(tgtmode)];
+    case 8 ... 12:
+        switch (tgtmode) {
+        case ARM_CPU_MODE_USR:
+            return env->usr_regs[regno - 8];
+        case ARM_CPU_MODE_FIQ:
+            return env->fiq_regs[regno - 8];
+        default:
+            g_assert_not_reached();
+        }
+    default:
+        g_assert_not_reached();
+    }
+}
+
+const void *HELPER(access_check_cp_reg)(CPUARMState *env, uint32_t key,
+                                        uint32_t syndrome, uint32_t isread)
+{
+    ARMCPU *cpu = env_archcpu(env);
+    const ARMCPRegInfo *ri = get_arm_cp_reginfo(cpu->cp_regs, key);
+    CPAccessResult res = CP_ACCESS_OK;
+    int target_el;
+
+    assert(ri != NULL);
+
+    if (arm_feature(env, ARM_FEATURE_XSCALE) && ri->cp < 14
+        && extract32(env->cp15.c15_cpar, ri->cp, 1) == 0) {
+        res = CP_ACCESS_TRAP;
+        goto fail;
+    }
+
+    if (ri->accessfn) {
+        res = ri->accessfn(env, ri, isread);
+    }
+
+    /*
+     * If the access function indicates a trap from EL0 to EL1 then
+     * that always takes priority over the HSTR_EL2 trap. (If it indicates
+     * a trap to EL3, then the HSTR_EL2 trap takes priority; if it indicates
+     * a trap to EL2, then the syndrome is the same either way so we don't
+     * care whether technically the architecture says that HSTR_EL2 trap or
+     * the other trap takes priority. So we take the "check HSTR_EL2" path
+     * for all of those cases.)
+     */
+    if (res != CP_ACCESS_OK && ((res & CP_ACCESS_EL_MASK) == 0) &&
+        arm_current_el(env) == 0) {
+        goto fail;
+    }
+
+    /*
+     * HSTR_EL2 traps from EL1 are checked earlier, in generated code;
+     * we only need to check here for traps from EL0.
+     */
+    if (!is_a64(env) && arm_current_el(env) == 0 && ri->cp == 15 &&
+        arm_is_el2_enabled(env) &&
+        (arm_hcr_el2_eff(env) & (HCR_E2H | HCR_TGE)) != (HCR_E2H | HCR_TGE)) {
+        uint32_t mask = 1 << ri->crn;
+
+        if (ri->type & ARM_CP_64BIT) {
+            mask = 1 << ri->crm;
+        }
+
+        /* T4 and T14 are RES0 */
+        mask &= ~((1 << 4) | (1 << 14));
+
+        if (env->cp15.hstr_el2 & mask) {
+            res = CP_ACCESS_TRAP_EL2;
+            goto fail;
+        }
+    }
+
+    /*
+     * Fine-grained traps also are lower priority than undef-to-EL1,
+     * higher priority than trap-to-EL3, and we don't care about priority
+     * order with other EL2 traps because the syndrome value is the same.
+     */
+    if (arm_fgt_active(env, arm_current_el(env))) {
+        uint64_t trapword = 0;
+        unsigned int idx = FIELD_EX32(ri->fgt, FGT, IDX);
+        unsigned int bitpos = FIELD_EX32(ri->fgt, FGT, BITPOS);
+        bool rev = FIELD_EX32(ri->fgt, FGT, REV);
+        bool trapbit;
+
+        if (ri->fgt & FGT_EXEC) {
+            assert(idx < ARRAY_SIZE(env->cp15.fgt_exec));
+            trapword = env->cp15.fgt_exec[idx];
+        } else if (isread && (ri->fgt & FGT_R)) {
+            assert(idx < ARRAY_SIZE(env->cp15.fgt_read));
+            trapword = env->cp15.fgt_read[idx];
+        } else if (!isread && (ri->fgt & FGT_W)) {
+            assert(idx < ARRAY_SIZE(env->cp15.fgt_write));
+            trapword = env->cp15.fgt_write[idx];
+        }
+
+        trapbit = extract64(trapword, bitpos, 1);
+        if (trapbit != rev) {
+            res = CP_ACCESS_TRAP_EL2;
+            goto fail;
+        }
+    }
+
+    if (likely(res == CP_ACCESS_OK)) {
+        return ri;
+    }
+
+ fail:
+    switch (res & ~CP_ACCESS_EL_MASK) {
+    case CP_ACCESS_TRAP:
+        break;
+    case CP_ACCESS_TRAP_UNCATEGORIZED:
+        /* Only CP_ACCESS_TRAP traps are direct to a specified EL */
+        assert((res & CP_ACCESS_EL_MASK) == 0);
+        if (cpu_isar_feature(aa64_ids, cpu) && isread &&
+            arm_cpreg_in_idspace(ri)) {
+            /*
+             * FEAT_IDST says this should be reported as EC_SYSTEMREGISTERTRAP,
+             * not EC_UNCATEGORIZED
+             */
+            break;
+        }
+        syndrome = syn_uncategorized();
+        break;
+    default:
+        g_assert_not_reached();
+    }
+
+    target_el = res & CP_ACCESS_EL_MASK;
+    switch (target_el) {
+    case 0:
+        target_el = exception_target_el(env);
+        break;
+    case 2:
+        assert(arm_current_el(env) != 3);
+        assert(arm_is_el2_enabled(env));
+        break;
+    case 3:
+        assert(arm_feature(env, ARM_FEATURE_EL3));
+        break;
+    default:
+        /* No "direct" traps to EL1 */
+        g_assert_not_reached();
+    }
+
+    raise_exception(env, EXCP_UDEF, syndrome, target_el);
+}
+
+const void *HELPER(lookup_cp_reg)(CPUARMState *env, uint32_t key)
+{
+    ARMCPU *cpu = env_archcpu(env);
+    const ARMCPRegInfo *ri = get_arm_cp_reginfo(cpu->cp_regs, key);
+
+    assert(ri != NULL);
+    return ri;
+}
+
+void HELPER(set_cp_reg)(CPUARMState *env, const void *rip, uint32_t value)
+{
+    const ARMCPRegInfo *ri = rip;
+
+    if (ri->type & ARM_CP_IO) {
+        qemu_mutex_lock_iothread();
+        ri->writefn(env, ri, value);
+        qemu_mutex_unlock_iothread();
+    } else {
+        ri->writefn(env, ri, value);
+    }
+}
+
+uint32_t HELPER(get_cp_reg)(CPUARMState *env, const void *rip)
+{
+    const ARMCPRegInfo *ri = rip;
+    uint32_t res;
+
+    if (ri->type & ARM_CP_IO) {
+        qemu_mutex_lock_iothread();
+        res = ri->readfn(env, ri);
+        qemu_mutex_unlock_iothread();
+    } else {
+        res = ri->readfn(env, ri);
+    }
+
+    return res;
+}
+
+void HELPER(set_cp_reg64)(CPUARMState *env, const void *rip, uint64_t value)
+{
+    const ARMCPRegInfo *ri = rip;
+
+    if (ri->type & ARM_CP_IO) {
+        qemu_mutex_lock_iothread();
+        ri->writefn(env, ri, value);
+        qemu_mutex_unlock_iothread();
+    } else {
+        ri->writefn(env, ri, value);
+    }
+}
+
+uint64_t HELPER(get_cp_reg64)(CPUARMState *env, const void *rip)
+{
+    const ARMCPRegInfo *ri = rip;
+    uint64_t res;
+
+    if (ri->type & ARM_CP_IO) {
+        qemu_mutex_lock_iothread();
+        res = ri->readfn(env, ri);
+        qemu_mutex_unlock_iothread();
+    } else {
+        res = ri->readfn(env, ri);
+    }
+
+    return res;
+}
+
+void HELPER(pre_hvc)(CPUARMState *env)
+{
+    ARMCPU *cpu = env_archcpu(env);
+    int cur_el = arm_current_el(env);
+    /* FIXME: Use actual secure state.  */
+    bool secure = false;
+    bool undef;
+
+    if (arm_is_psci_call(cpu, EXCP_HVC)) {
+        /* If PSCI is enabled and this looks like a valid PSCI call then
+         * that overrides the architecturally mandated HVC behaviour.
+         */
+        return;
+    }
+
+    if (!arm_feature(env, ARM_FEATURE_EL2)) {
+        /* If EL2 doesn't exist, HVC always UNDEFs */
+        undef = true;
+    } else if (arm_feature(env, ARM_FEATURE_EL3)) {
+        /* EL3.HCE has priority over EL2.HCD. */
+        undef = !(env->cp15.scr_el3 & SCR_HCE);
+    } else {
+        undef = env->cp15.hcr_el2 & HCR_HCD;
+    }
+
+    /* In ARMv7 and ARMv8/AArch32, HVC is undef in secure state.
+     * For ARMv8/AArch64, HVC is allowed in EL3.
+     * Note that we've already trapped HVC from EL0 at translation
+     * time.
+     */
+    if (secure && (!is_a64(env) || cur_el == 1)) {
+        undef = true;
+    }
+
+    if (undef) {
+        raise_exception(env, EXCP_UDEF, syn_uncategorized(),
+                        exception_target_el(env));
+    }
+}
+
+void HELPER(pre_smc)(CPUARMState *env, uint32_t syndrome)
+{
+    ARMCPU *cpu = env_archcpu(env);
+    int cur_el = arm_current_el(env);
+    bool secure = arm_is_secure(env);
+    bool smd_flag = env->cp15.scr_el3 & SCR_SMD;
+
+    /*
+     * SMC behaviour is summarized in the following table.
+     * This helper handles the "Trap to EL2" and "Undef insn" cases.
+     * The "Trap to EL3" and "PSCI call" cases are handled in the exception
+     * helper.
+     *
+     *  -> ARM_FEATURE_EL3 and !SMD
+     *                           HCR_TSC && NS EL1   !HCR_TSC || !NS EL1
+     *
+     *  Conduit SMC, valid call  Trap to EL2         PSCI Call
+     *  Conduit SMC, inval call  Trap to EL2         Trap to EL3
+     *  Conduit not SMC          Trap to EL2         Trap to EL3
+     *
+     *
+     *  -> ARM_FEATURE_EL3 and SMD
+     *                           HCR_TSC && NS EL1   !HCR_TSC || !NS EL1
+     *
+     *  Conduit SMC, valid call  Trap to EL2         PSCI Call
+     *  Conduit SMC, inval call  Trap to EL2         Undef insn
+     *  Conduit not SMC          Trap to EL2         Undef insn
+     *
+     *
+     *  -> !ARM_FEATURE_EL3
+     *                           HCR_TSC && NS EL1   !HCR_TSC || !NS EL1
+     *
+     *  Conduit SMC, valid call  Trap to EL2         PSCI Call
+     *  Conduit SMC, inval call  Trap to EL2         Undef insn
+     *  Conduit not SMC          Undef insn          Undef insn
+     */
+
+    /* On ARMv8 with EL3 AArch64, SMD applies to both S and NS state.
+     * On ARMv8 with EL3 AArch32, or ARMv7 with the Virtualization
+     *  extensions, SMD only applies to NS state.
+     * On ARMv7 without the Virtualization extensions, the SMD bit
+     * doesn't exist, but we forbid the guest to set it to 1 in scr_write(),
+     * so we need not special case this here.
+     */
+    bool smd = arm_feature(env, ARM_FEATURE_AARCH64) ? smd_flag
+                                                     : smd_flag && !secure;
+
+    if (!arm_feature(env, ARM_FEATURE_EL3) &&
+        cpu->psci_conduit != QEMU_PSCI_CONDUIT_SMC) {
+        /* If we have no EL3 then SMC always UNDEFs and can't be
+         * trapped to EL2. PSCI-via-SMC is a sort of ersatz EL3
+         * firmware within QEMU, and we want an EL2 guest to be able
+         * to forbid its EL1 from making PSCI calls into QEMU's
+         * "firmware" via HCR.TSC, so for these purposes treat
+         * PSCI-via-SMC as implying an EL3.
+         * This handles the very last line of the previous table.
+         */
+        raise_exception(env, EXCP_UDEF, syn_uncategorized(),
+                        exception_target_el(env));
+    }
+
+    if (cur_el == 1 && (arm_hcr_el2_eff(env) & HCR_TSC)) {
+        /* In NS EL1, HCR controlled routing to EL2 has priority over SMD.
+         * We also want an EL2 guest to be able to forbid its EL1 from
+         * making PSCI calls into QEMU's "firmware" via HCR.TSC.
+         * This handles all the "Trap to EL2" cases of the previous table.
+         */
+        raise_exception(env, EXCP_HYP_TRAP, syndrome, 2);
+    }
+
+    /* Catch the two remaining "Undef insn" cases of the previous table:
+     *    - PSCI conduit is SMC but we don't have a valid PCSI call,
+     *    - We don't have EL3 or SMD is set.
+     */
+    if (!arm_is_psci_call(cpu, EXCP_SMC) &&
+        (smd || !arm_feature(env, ARM_FEATURE_EL3))) {
+        raise_exception(env, EXCP_UDEF, syn_uncategorized(),
+                        exception_target_el(env));
+    }
+}
+
+/* ??? Flag setting arithmetic is awkward because we need to do comparisons.
+   The only way to do that in TCG is a conditional branch, which clobbers
+   all our temporaries.  For now implement these as helper functions.  */
+
+/* Similarly for variable shift instructions.  */
+
+uint32_t HELPER(shl_cc)(CPUARMState *env, uint32_t x, uint32_t i)
+{
+    int shift = i & 0xff;
+    if (shift >= 32) {
+        if (shift == 32)
+            env->CF = x & 1;
+        else
+            env->CF = 0;
+        return 0;
+    } else if (shift != 0) {
+        env->CF = (x >> (32 - shift)) & 1;
+        return x << shift;
+    }
+    return x;
+}
+
+uint32_t HELPER(shr_cc)(CPUARMState *env, uint32_t x, uint32_t i)
+{
+    int shift = i & 0xff;
+    if (shift >= 32) {
+        if (shift == 32)
+            env->CF = (x >> 31) & 1;
+        else
+            env->CF = 0;
+        return 0;
+    } else if (shift != 0) {
+        env->CF = (x >> (shift - 1)) & 1;
+        return x >> shift;
+    }
+    return x;
+}
+
+uint32_t HELPER(sar_cc)(CPUARMState *env, uint32_t x, uint32_t i)
+{
+    int shift = i & 0xff;
+    if (shift >= 32) {
+        env->CF = (x >> 31) & 1;
+        return (int32_t)x >> 31;
+    } else if (shift != 0) {
+        env->CF = (x >> (shift - 1)) & 1;
+        return (int32_t)x >> shift;
+    }
+    return x;
+}
+
+uint32_t HELPER(ror_cc)(CPUARMState *env, uint32_t x, uint32_t i)
+{
+    int shift1, shift;
+    shift1 = i & 0xff;
+    shift = shift1 & 0x1f;
+    if (shift == 0) {
+        if (shift1 != 0)
+            env->CF = (x >> 31) & 1;
+        return x;
+    } else {
+        env->CF = (x >> (shift - 1)) & 1;
+        return ((uint32_t)x >> shift) | (x << (32 - shift));
+    }
+}
+
+void HELPER(probe_access)(CPUARMState *env, target_ulong ptr,
+                          uint32_t access_type, uint32_t mmu_idx,
+                          uint32_t size)
+{
+    uint32_t in_page = -((uint32_t)ptr | TARGET_PAGE_SIZE);
+    uintptr_t ra = GETPC();
+
+    if (likely(size <= in_page)) {
+        probe_access(env, ptr, size, access_type, mmu_idx, ra);
+    } else {
+        probe_access(env, ptr, in_page, access_type, mmu_idx, ra);
+        probe_access(env, ptr + in_page, size - in_page,
+                     access_type, mmu_idx, ra);
+    }
+}
+
+/*
+ * This function corresponds to AArch64.vESBOperation().
+ * Note that the AArch32 version is not functionally different.
+ */
+void HELPER(vesb)(CPUARMState *env)
+{
+    /*
+     * The EL2Enabled() check is done inside arm_hcr_el2_eff,
+     * and will return HCR_EL2.VSE == 0, so nothing happens.
+     */
+    uint64_t hcr = arm_hcr_el2_eff(env);
+    bool enabled = !(hcr & HCR_TGE) && (hcr & HCR_AMO);
+    bool pending = enabled && (hcr & HCR_VSE);
+    bool masked  = (env->daif & PSTATE_A);
+
+    /* If VSE pending and masked, defer the exception.  */
+    if (pending && masked) {
+        uint32_t syndrome;
+
+        if (arm_el_is_aa64(env, 1)) {
+            /* Copy across IDS and ISS from VSESR. */
+            syndrome = env->cp15.vsesr_el2 & 0x1ffffff;
+        } else {
+            ARMMMUFaultInfo fi = { .type = ARMFault_AsyncExternal };
+
+            if (extended_addresses_enabled(env)) {
+                syndrome = arm_fi_to_lfsc(&fi);
+            } else {
+                syndrome = arm_fi_to_sfsc(&fi);
+            }
+            /* Copy across AET and ExT from VSESR. */
+            syndrome |= env->cp15.vsesr_el2 & 0xd000;
+        }
+
+        /* Set VDISR_EL2.A along with the syndrome. */
+        env->cp15.vdisr_el2 = syndrome | (1u << 31);
+
+        /* Clear pending virtual SError */
+        env->cp15.hcr_el2 &= ~HCR_VSE;
+        cpu_reset_interrupt(env_cpu(env), CPU_INTERRUPT_VSERR);
+    }
+}