diff options
Diffstat (limited to 'target/riscv/cpu_helper.c')
-rw-r--r-- | target/riscv/cpu_helper.c | 954 |
1 files changed, 795 insertions, 159 deletions
diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c index 395a1d9..2ed69d7 100644 --- a/target/riscv/cpu_helper.c +++ b/target/riscv/cpu_helper.c @@ -23,16 +23,19 @@ #include "cpu.h" #include "internals.h" #include "pmu.h" -#include "exec/exec-all.h" +#include "exec/cputlb.h" #include "exec/page-protection.h" +#include "exec/target_page.h" +#include "system/memory.h" #include "instmap.h" #include "tcg/tcg-op.h" +#include "accel/tcg/cpu-ops.h" #include "trace.h" #include "semihosting/common-semi.h" -#include "sysemu/cpu-timers.h" +#include "exec/icount.h" #include "cpu_bits.h" #include "debug.h" -#include "tcg/oversized-guest.h" +#include "pmp.h" int riscv_env_mmu_index(CPURISCVState *env, bool ifetch) { @@ -63,134 +66,169 @@ int riscv_env_mmu_index(CPURISCVState *env, bool ifetch) #endif } -void cpu_get_tb_cpu_state(CPURISCVState *env, vaddr *pc, - uint64_t *cs_base, uint32_t *pflags) +bool cpu_get_fcfien(CPURISCVState *env) { - RISCVCPU *cpu = env_archcpu(env); - RISCVExtStatus fs, vs; - uint32_t flags = 0; + /* no cfi extension, return false */ + if (!env_archcpu(env)->cfg.ext_zicfilp) { + return false; + } - *pc = env->xl == MXL_RV32 ? env->pc & UINT32_MAX : env->pc; - *cs_base = 0; + switch (env->priv) { + case PRV_U: + if (riscv_has_ext(env, RVS)) { + return env->senvcfg & SENVCFG_LPE; + } + return env->menvcfg & MENVCFG_LPE; +#ifndef CONFIG_USER_ONLY + case PRV_S: + if (env->virt_enabled) { + return env->henvcfg & HENVCFG_LPE; + } + return env->menvcfg & MENVCFG_LPE; + case PRV_M: + return env->mseccfg & MSECCFG_MLPE; +#endif + default: + g_assert_not_reached(); + } +} - if (cpu->cfg.ext_zve32x) { +bool cpu_get_bcfien(CPURISCVState *env) +{ + /* no cfi extension, return false */ + if (!env_archcpu(env)->cfg.ext_zicfiss) { + return false; + } + + switch (env->priv) { + case PRV_U: /* - * If env->vl equals to VLMAX, we can use generic vector operation - * expanders (GVEC) to accerlate the vector operations. - * However, as LMUL could be a fractional number. The maximum - * vector size can be operated might be less than 8 bytes, - * which is not supported by GVEC. So we set vl_eq_vlmax flag to true - * only when maxsz >= 8 bytes. + * If S is not implemented then shadow stack for U can't be turned on + * It is checked in `riscv_cpu_validate_set_extensions`, so no need to + * check here or assert here */ - - /* lmul encoded as in DisasContext::lmul */ - int8_t lmul = sextract32(FIELD_EX64(env->vtype, VTYPE, VLMUL), 0, 3); - uint32_t vsew = FIELD_EX64(env->vtype, VTYPE, VSEW); - uint32_t vlmax = vext_get_vlmax(cpu->cfg.vlenb, vsew, lmul); - uint32_t maxsz = vlmax << vsew; - bool vl_eq_vlmax = (env->vstart == 0) && (vlmax == env->vl) && - (maxsz >= 8); - flags = FIELD_DP32(flags, TB_FLAGS, VILL, env->vill); - flags = FIELD_DP32(flags, TB_FLAGS, SEW, vsew); - flags = FIELD_DP32(flags, TB_FLAGS, LMUL, - FIELD_EX64(env->vtype, VTYPE, VLMUL)); - flags = FIELD_DP32(flags, TB_FLAGS, VL_EQ_VLMAX, vl_eq_vlmax); - flags = FIELD_DP32(flags, TB_FLAGS, VTA, - FIELD_EX64(env->vtype, VTYPE, VTA)); - flags = FIELD_DP32(flags, TB_FLAGS, VMA, - FIELD_EX64(env->vtype, VTYPE, VMA)); - flags = FIELD_DP32(flags, TB_FLAGS, VSTART_EQ_ZERO, env->vstart == 0); - } else { - flags = FIELD_DP32(flags, TB_FLAGS, VILL, 1); + return env->senvcfg & SENVCFG_SSE; +#ifndef CONFIG_USER_ONLY + case PRV_S: + if (env->virt_enabled) { + return env->henvcfg & HENVCFG_SSE; + } + return env->menvcfg & MENVCFG_SSE; + case PRV_M: /* M-mode shadow stack is always off */ + return false; +#endif + default: + g_assert_not_reached(); } +} +bool riscv_env_smode_dbltrp_enabled(CPURISCVState *env, bool virt) +{ #ifdef CONFIG_USER_ONLY - fs = EXT_STATUS_DIRTY; - vs = EXT_STATUS_DIRTY; + return false; #else - flags = FIELD_DP32(flags, TB_FLAGS, PRIV, env->priv); - - flags |= riscv_env_mmu_index(env, 0); - fs = get_field(env->mstatus, MSTATUS_FS); - vs = get_field(env->mstatus, MSTATUS_VS); - - if (env->virt_enabled) { - flags = FIELD_DP32(flags, TB_FLAGS, VIRT_ENABLED, 1); - /* - * Merge DISABLED and !DIRTY states using MIN. - * We will set both fields when dirtying. - */ - fs = MIN(fs, get_field(env->mstatus_hs, MSTATUS_FS)); - vs = MIN(vs, get_field(env->mstatus_hs, MSTATUS_VS)); + if (virt) { + return (env->henvcfg & HENVCFG_DTE) != 0; + } else { + return (env->menvcfg & MENVCFG_DTE) != 0; } +#endif +} - /* With Zfinx, floating point is enabled/disabled by Smstateen. */ - if (!riscv_has_ext(env, RVF)) { - fs = (smstateen_acc_ok(env, 0, SMSTATEEN0_FCSR) == RISCV_EXCP_NONE) - ? EXT_STATUS_DIRTY : EXT_STATUS_DISABLED; - } +RISCVPmPmm riscv_pm_get_pmm(CPURISCVState *env) +{ +#ifndef CONFIG_USER_ONLY + int priv_mode = cpu_address_mode(env); - if (cpu->cfg.debug && !icount_enabled()) { - flags = FIELD_DP32(flags, TB_FLAGS, ITRIGGER, env->itrigger_enabled); + if (get_field(env->mstatus, MSTATUS_MPRV) && + get_field(env->mstatus, MSTATUS_MXR)) { + return PMM_FIELD_DISABLED; } -#endif - flags = FIELD_DP32(flags, TB_FLAGS, FS, fs); - flags = FIELD_DP32(flags, TB_FLAGS, VS, vs); - flags = FIELD_DP32(flags, TB_FLAGS, XL, env->xl); - flags = FIELD_DP32(flags, TB_FLAGS, AXL, cpu_address_xl(env)); - if (env->cur_pmmask != 0) { - flags = FIELD_DP32(flags, TB_FLAGS, PM_MASK_ENABLED, 1); - } - if (env->cur_pmbase != 0) { - flags = FIELD_DP32(flags, TB_FLAGS, PM_BASE_ENABLED, 1); + /* Get current PMM field */ + switch (priv_mode) { + case PRV_M: + if (riscv_cpu_cfg(env)->ext_smmpm) { + return get_field(env->mseccfg, MSECCFG_PMM); + } + break; + case PRV_S: + if (riscv_cpu_cfg(env)->ext_smnpm) { + if (get_field(env->mstatus, MSTATUS_MPV)) { + return get_field(env->henvcfg, HENVCFG_PMM); + } else { + return get_field(env->menvcfg, MENVCFG_PMM); + } + } + break; + case PRV_U: + if (riscv_has_ext(env, RVS)) { + if (riscv_cpu_cfg(env)->ext_ssnpm) { + return get_field(env->senvcfg, SENVCFG_PMM); + } + } else { + if (riscv_cpu_cfg(env)->ext_smnpm) { + return get_field(env->menvcfg, MENVCFG_PMM); + } + } + break; + default: + g_assert_not_reached(); } - - *pflags = flags; + return PMM_FIELD_DISABLED; +#else + return PMM_FIELD_DISABLED; +#endif } -void riscv_cpu_update_mask(CPURISCVState *env) +RISCVPmPmm riscv_pm_get_virt_pmm(CPURISCVState *env) { - target_ulong mask = 0, base = 0; - RISCVMXL xl = env->xl; - /* - * TODO: Current RVJ spec does not specify - * how the extension interacts with XLEN. - */ #ifndef CONFIG_USER_ONLY - int mode = cpu_address_mode(env); - xl = cpu_get_xl(env, mode); - if (riscv_has_ext(env, RVJ)) { - switch (mode) { - case PRV_M: - if (env->mmte & M_PM_ENABLE) { - mask = env->mpmmask; - base = env->mpmbase; - } - break; - case PRV_S: - if (env->mmte & S_PM_ENABLE) { - mask = env->spmmask; - base = env->spmbase; - } - break; - case PRV_U: - if (env->mmte & U_PM_ENABLE) { - mask = env->upmmask; - base = env->upmbase; - } - break; - default: - g_assert_not_reached(); + int priv_mode = cpu_address_mode(env); + + if (priv_mode == PRV_U) { + return get_field(env->hstatus, HSTATUS_HUPMM); + } else { + if (get_field(env->hstatus, HSTATUS_SPVP)) { + return get_field(env->henvcfg, HENVCFG_PMM); + } else { + return get_field(env->senvcfg, SENVCFG_PMM); } } +#else + return PMM_FIELD_DISABLED; #endif - if (xl == MXL_RV32) { - env->cur_pmmask = mask & UINT32_MAX; - env->cur_pmbase = base & UINT32_MAX; +} + +bool riscv_cpu_virt_mem_enabled(CPURISCVState *env) +{ +#ifndef CONFIG_USER_ONLY + int satp_mode = 0; + int priv_mode = cpu_address_mode(env); + + if (riscv_cpu_mxl(env) == MXL_RV32) { + satp_mode = get_field(env->satp, SATP32_MODE); } else { - env->cur_pmmask = mask; - env->cur_pmbase = base; + satp_mode = get_field(env->satp, SATP64_MODE); + } + + return ((satp_mode != VM_1_10_MBARE) && (priv_mode != PRV_M)); +#else + return false; +#endif +} + +uint32_t riscv_pm_get_pmlen(RISCVPmPmm pmm) +{ + switch (pmm) { + case PMM_FIELD_DISABLED: + return 0; + case PMM_FIELD_PMLEN7: + return 7; + case PMM_FIELD_PMLEN16: + return 16; + default: + g_assert_not_reached(); } } @@ -434,6 +472,18 @@ static int riscv_cpu_local_irq_pending(CPURISCVState *env) uint64_t vsbits, irq_delegated; int virq; + /* Priority: RNMI > Other interrupt. */ + if (riscv_cpu_cfg(env)->ext_smrnmi) { + /* If mnstatus.NMIE == 0, all interrupts are disabled. */ + if (!get_field(env->mnstatus, MNSTATUS_NMIE)) { + return RISCV_EXCP_NONE; + } + + if (env->rnmip) { + return ctz64(env->rnmip); /* since non-zero */ + } + } + /* Determine interrupt enable state of all privilege modes */ if (env->virt_enabled) { mie = 1; @@ -496,7 +546,9 @@ static int riscv_cpu_local_irq_pending(CPURISCVState *env) bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request) { - if (interrupt_request & CPU_INTERRUPT_HARD) { + uint32_t mask = CPU_INTERRUPT_HARD | CPU_INTERRUPT_RNMI; + + if (interrupt_request & mask) { RISCVCPU *cpu = RISCV_CPU(cs); CPURISCVState *env = &cpu->env; int interruptno = riscv_cpu_local_irq_pending(env); @@ -546,8 +598,21 @@ void riscv_cpu_swap_hypervisor_regs(CPURISCVState *env) } bool current_virt = env->virt_enabled; + /* + * If zicfilp extension available and henvcfg.LPE = 1, + * then apply SPELP mask on mstatus + */ + if (env_archcpu(env)->cfg.ext_zicfilp && + get_field(env->henvcfg, HENVCFG_LPE)) { + mstatus_mask |= SSTATUS_SPELP; + } + g_assert(riscv_has_ext(env, RVH)); + if (riscv_env_smode_dbltrp_enabled(env, current_virt)) { + mstatus_mask |= MSTATUS_SDT; + } + if (current_virt) { /* Current V=1 and we are about to change to V=0 */ env->vsstatus = env->mstatus & mstatus_mask; @@ -619,6 +684,30 @@ void riscv_cpu_set_geilen(CPURISCVState *env, target_ulong geilen) env->geilen = geilen; } +void riscv_cpu_set_rnmi(RISCVCPU *cpu, uint32_t irq, bool level) +{ + CPURISCVState *env = &cpu->env; + CPUState *cs = CPU(cpu); + bool release_lock = false; + + if (!bql_locked()) { + release_lock = true; + bql_lock(); + } + + if (level) { + env->rnmip |= 1 << irq; + cpu_interrupt(cs, CPU_INTERRUPT_RNMI); + } else { + env->rnmip &= ~(1 << irq); + cpu_reset_interrupt(cs, CPU_INTERRUPT_RNMI); + } + + if (release_lock) { + bql_unlock(); + } +} + int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint64_t interrupts) { CPURISCVState *env = &cpu->env; @@ -691,6 +780,254 @@ void riscv_cpu_set_aia_ireg_rmw_fn(CPURISCVState *env, uint32_t priv, } } +static void riscv_ctr_freeze(CPURISCVState *env, uint64_t freeze_mask, + bool virt) +{ + uint64_t ctl = virt ? env->vsctrctl : env->mctrctl; + + assert((freeze_mask & (~(XCTRCTL_BPFRZ | XCTRCTL_LCOFIFRZ))) == 0); + + if (ctl & freeze_mask) { + env->sctrstatus |= SCTRSTATUS_FROZEN; + } +} + +void riscv_ctr_clear(CPURISCVState *env) +{ + memset(env->ctr_src, 0x0, sizeof(env->ctr_src)); + memset(env->ctr_dst, 0x0, sizeof(env->ctr_dst)); + memset(env->ctr_data, 0x0, sizeof(env->ctr_data)); +} + +static uint64_t riscv_ctr_priv_to_mask(target_ulong priv, bool virt) +{ + switch (priv) { + case PRV_M: + return MCTRCTL_M; + case PRV_S: + if (virt) { + return XCTRCTL_S; + } + return XCTRCTL_S; + case PRV_U: + if (virt) { + return XCTRCTL_U; + } + return XCTRCTL_U; + } + + g_assert_not_reached(); +} + +static uint64_t riscv_ctr_get_control(CPURISCVState *env, target_long priv, + bool virt) +{ + switch (priv) { + case PRV_M: + return env->mctrctl; + case PRV_S: + case PRV_U: + if (virt) { + return env->vsctrctl; + } + return env->mctrctl; + } + + g_assert_not_reached(); +} + +/* + * This function assumes that src privilege and target privilege are not same + * and src privilege is less than target privilege. This includes the virtual + * state as well. + */ +static bool riscv_ctr_check_xte(CPURISCVState *env, target_long src_prv, + bool src_virt) +{ + target_long tgt_prv = env->priv; + bool res = true; + + /* + * VS and U mode are same in terms of xTE bits required to record an + * external trap. See 6.1.2. External Traps, table 8 External Trap Enable + * Requirements. This changes VS to U to simplify the logic a bit. + */ + if (src_virt && src_prv == PRV_S) { + src_prv = PRV_U; + } else if (env->virt_enabled && tgt_prv == PRV_S) { + tgt_prv = PRV_U; + } + + /* VU mode is an outlier here. */ + if (src_virt && src_prv == PRV_U) { + res &= !!(env->vsctrctl & XCTRCTL_STE); + } + + switch (src_prv) { + case PRV_U: + if (tgt_prv == PRV_U) { + break; + } + res &= !!(env->mctrctl & XCTRCTL_STE); + /* fall-through */ + case PRV_S: + if (tgt_prv == PRV_S) { + break; + } + res &= !!(env->mctrctl & MCTRCTL_MTE); + /* fall-through */ + case PRV_M: + break; + } + + return res; +} + +/* + * Special cases for traps and trap returns: + * + * 1- Traps, and trap returns, between enabled modes are recorded as normal. + * 2- Traps from an inhibited mode to an enabled mode, and trap returns from an + * enabled mode back to an inhibited mode, are partially recorded. In such + * cases, the PC from the inhibited mode (source PC for traps, and target PC + * for trap returns) is 0. + * + * 3- Trap returns from an inhibited mode to an enabled mode are not recorded. + * Traps from an enabled mode to an inhibited mode, known as external traps, + * receive special handling. + * By default external traps are not recorded, but a handshake mechanism exists + * to allow partial recording. Software running in the target mode of the trap + * can opt-in to allowing CTR to record traps into that mode even when the mode + * is inhibited. The MTE, STE, and VSTE bits allow M-mode, S-mode, and VS-mode, + * respectively, to opt-in. When an External Trap occurs, and xTE=1, such that + * x is the target privilege mode of the trap, will CTR record the trap. In such + * cases, the target PC is 0. + */ +/* + * CTR arrays are implemented as circular buffers and new entry is stored at + * sctrstatus.WRPTR, but they are presented to software as moving circular + * buffers. Which means, software get's the illusion that whenever a new entry + * is added the whole buffer is moved by one place and the new entry is added at + * the start keeping new entry at idx 0 and older ones follow. + * + * Depth = 16. + * + * buffer [0] [1] [2] [3] [4] [5] [6] [7] [8] [9] [A] [B] [C] [D] [E] [F] + * WRPTR W + * entry 7 6 5 4 3 2 1 0 F E D C B A 9 8 + * + * When a new entry is added: + * buffer [0] [1] [2] [3] [4] [5] [6] [7] [8] [9] [A] [B] [C] [D] [E] [F] + * WRPTR W + * entry 8 7 6 5 4 3 2 1 0 F E D C B A 9 + * + * entry here denotes the logical entry number that software can access + * using ctrsource, ctrtarget and ctrdata registers. So xiselect 0x200 + * will return entry 0 i-e buffer[8] and 0x201 will return entry 1 i-e + * buffer[7]. Here is how we convert entry to buffer idx. + * + * entry = isel - CTR_ENTRIES_FIRST; + * idx = (sctrstatus.WRPTR - entry - 1) & (depth - 1); + */ +void riscv_ctr_add_entry(CPURISCVState *env, target_long src, target_long dst, + enum CTRType type, target_ulong src_priv, bool src_virt) +{ + bool tgt_virt = env->virt_enabled; + uint64_t src_mask = riscv_ctr_priv_to_mask(src_priv, src_virt); + uint64_t tgt_mask = riscv_ctr_priv_to_mask(env->priv, tgt_virt); + uint64_t src_ctrl = riscv_ctr_get_control(env, src_priv, src_virt); + uint64_t tgt_ctrl = riscv_ctr_get_control(env, env->priv, tgt_virt); + uint64_t depth, head; + bool ext_trap = false; + + /* + * Return immediately if both target and src recording is disabled or if + * CTR is in frozen state. + */ + if ((!(src_ctrl & src_mask) && !(tgt_ctrl & tgt_mask)) || + env->sctrstatus & SCTRSTATUS_FROZEN) { + return; + } + + /* + * With RAS Emul enabled, only allow Indirect, direct calls, Function + * returns and Co-routine swap types. + */ + if (tgt_ctrl & XCTRCTL_RASEMU && + type != CTRDATA_TYPE_INDIRECT_CALL && + type != CTRDATA_TYPE_DIRECT_CALL && + type != CTRDATA_TYPE_RETURN && + type != CTRDATA_TYPE_CO_ROUTINE_SWAP) { + return; + } + + if (type == CTRDATA_TYPE_EXCEPTION || type == CTRDATA_TYPE_INTERRUPT) { + /* Case 2 for traps. */ + if (!(src_ctrl & src_mask)) { + src = 0; + } else if (!(tgt_ctrl & tgt_mask)) { + /* Check if target priv-mode has allowed external trap recording. */ + if (!riscv_ctr_check_xte(env, src_priv, src_virt)) { + return; + } + + ext_trap = true; + dst = 0; + } + } else if (type == CTRDATA_TYPE_EXCEP_INT_RET) { + /* + * Case 3 for trap returns. Trap returns from inhibited mode are not + * recorded. + */ + if (!(src_ctrl & src_mask)) { + return; + } + + /* Case 2 for trap returns. */ + if (!(tgt_ctrl & tgt_mask)) { + dst = 0; + } + } + + /* Ignore filters in case of RASEMU mode or External trap. */ + if (!(tgt_ctrl & XCTRCTL_RASEMU) && !ext_trap) { + /* + * Check if the specific type is inhibited. Not taken branch filter is + * an enable bit and needs to be checked separatly. + */ + bool check = tgt_ctrl & BIT_ULL(type + XCTRCTL_INH_START); + if ((type == CTRDATA_TYPE_NONTAKEN_BRANCH && !check) || + (type != CTRDATA_TYPE_NONTAKEN_BRANCH && check)) { + return; + } + } + + head = get_field(env->sctrstatus, SCTRSTATUS_WRPTR_MASK); + + depth = 16 << get_field(env->sctrdepth, SCTRDEPTH_MASK); + if (tgt_ctrl & XCTRCTL_RASEMU && type == CTRDATA_TYPE_RETURN) { + head = (head - 1) & (depth - 1); + + env->ctr_src[head] &= ~CTRSOURCE_VALID; + env->sctrstatus = + set_field(env->sctrstatus, SCTRSTATUS_WRPTR_MASK, head); + return; + } + + /* In case of Co-routine SWAP we overwrite latest entry. */ + if (tgt_ctrl & XCTRCTL_RASEMU && type == CTRDATA_TYPE_CO_ROUTINE_SWAP) { + head = (head - 1) & (depth - 1); + } + + env->ctr_src[head] = src | CTRSOURCE_VALID; + env->ctr_dst[head] = dst & ~CTRTARGET_MISP; + env->ctr_data[head] = set_field(0, CTRDATA_TYPE_MASK, type); + + head = (head + 1) & (depth - 1); + + env->sctrstatus = set_field(env->sctrstatus, SCTRSTATUS_WRPTR_MASK, head); +} + void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv, bool virt_en) { g_assert(newpriv <= PRV_M && newpriv != PRV_RESERVED); @@ -706,7 +1043,6 @@ void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv, bool virt_en) /* tlb_flush is unnecessary as mode is contained in mmu_idx */ env->priv = newpriv; env->xl = cpu_recompute_xl(env); - riscv_cpu_update_mask(env); /* * Clear the load reservation - otherwise a reservation placed in one @@ -777,6 +1113,55 @@ static int get_physical_address_pmp(CPURISCVState *env, int *prot, hwaddr addr, return TRANSLATE_SUCCESS; } +/* Returns 'true' if a svukte address check is needed */ +static bool do_svukte_check(CPURISCVState *env, bool first_stage, + int mode, bool virt) +{ + /* Svukte extension depends on Sv39. */ + if (!(env_archcpu(env)->cfg.ext_svukte || + !first_stage || + VM_1_10_SV39 != get_field(env->satp, SATP64_MODE))) { + return false; + } + + /* + * Check hstatus.HUKTE if the effective mode is switched to VU-mode by + * executing HLV/HLVX/HSV in U-mode. + * For other cases, check senvcfg.UKTE. + */ + if (env->priv == PRV_U && !env->virt_enabled && virt) { + if (!get_field(env->hstatus, HSTATUS_HUKTE)) { + return false; + } + } else if (!get_field(env->senvcfg, SENVCFG_UKTE)) { + return false; + } + + /* + * Svukte extension is qualified only in U or VU-mode. + * + * Effective mode can be switched to U or VU-mode by: + * - M-mode + mstatus.MPRV=1 + mstatus.MPP=U-mode. + * - Execute HLV/HLVX/HSV from HS-mode + hstatus.SPVP=0. + * - U-mode. + * - VU-mode. + * - Execute HLV/HLVX/HSV from U-mode + hstatus.HU=1. + */ + if (mode != PRV_U) { + return false; + } + + return true; +} + +static bool check_svukte_addr(CPURISCVState *env, vaddr addr) +{ + /* svukte extension excludes RV32 */ + uint32_t sxlen = 32 * riscv_cpu_sxl(env); + uint64_t high_bit = addr & (1UL << (sxlen - 1)); + return !high_bit; +} + /* * get_physical_address - get the physical address for this virtual address * @@ -804,7 +1189,7 @@ static int get_physical_address(CPURISCVState *env, hwaddr *physical, target_ulong *fault_pte_addr, int access_type, int mmu_idx, bool first_stage, bool two_stage, - bool is_debug) + bool is_debug, bool is_probe) { /* * NOTE: the env->pc value visible here will not be @@ -814,10 +1199,18 @@ static int get_physical_address(CPURISCVState *env, hwaddr *physical, MemTxResult res; MemTxAttrs attrs = MEMTXATTRS_UNSPECIFIED; int mode = mmuidx_priv(mmu_idx); + bool virt = mmuidx_2stage(mmu_idx); bool use_background = false; hwaddr ppn; int napot_bits = 0; target_ulong napot_mask; + bool is_sstack_idx = ((mmu_idx & MMU_IDX_SS_WRITE) == MMU_IDX_SS_WRITE); + bool sstack_page = false; + + if (do_svukte_check(env, first_stage, mode, virt) && + !check_svukte_addr(env, addr)) { + return TRANSLATE_FAIL; + } /* * Check if we should use the background registers for the two @@ -890,12 +1283,14 @@ static int get_physical_address(CPURISCVState *env, hwaddr *physical, CPUState *cs = env_cpu(env); int va_bits = PGSHIFT + levels * ptidxbits + widened; + int sxlen = 16 << riscv_cpu_sxl(env); + int sxlen_bytes = sxlen / 8; if (first_stage == true) { target_ulong mask, masked_msbs; - if (TARGET_LONG_BITS > (va_bits - 1)) { - mask = (1L << (TARGET_LONG_BITS - (va_bits - 1))) - 1; + if (sxlen > (va_bits - 1)) { + mask = (1L << (sxlen - (va_bits - 1))) - 1; } else { mask = 0; } @@ -925,9 +1320,7 @@ static int get_physical_address(CPURISCVState *env, hwaddr *physical, hwaddr pte_addr; int i; -#if !TCG_OVERSIZED_GUEST -restart: -#endif + restart: for (i = 0; i < levels; i++, ptshift -= ptidxbits) { target_ulong idx; if (i == 0) { @@ -948,7 +1341,7 @@ restart: int vbase_ret = get_physical_address(env, &vbase, &vbase_prot, base, NULL, MMU_DATA_LOAD, MMUIdx_U, false, true, - is_debug); + is_debug, false); if (vbase_ret != TRANSLATE_SUCCESS) { if (fault_pte_addr) { @@ -964,7 +1357,7 @@ restart: int pmp_prot; int pmp_ret = get_physical_address_pmp(env, &pmp_prot, pte_addr, - sizeof(target_ulong), + sxlen_bytes, MMU_DATA_LOAD, PRV_S); if (pmp_ret != TRANSLATE_SUCCESS) { return TRANSLATE_PMP_FAIL; @@ -984,14 +1377,27 @@ restart: ppn = pte >> PTE_PPN_SHIFT; } else { if (pte & PTE_RESERVED) { + qemu_log_mask(LOG_GUEST_ERROR, "%s: reserved bits set in PTE: " + "addr: 0x%" HWADDR_PRIx " pte: 0x" TARGET_FMT_lx "\n", + __func__, pte_addr, pte); return TRANSLATE_FAIL; } if (!pbmte && (pte & PTE_PBMT)) { + /* Reserved without Svpbmt. */ + qemu_log_mask(LOG_GUEST_ERROR, "%s: PBMT bits set in PTE, " + "and Svpbmt extension is disabled: " + "addr: 0x%" HWADDR_PRIx " pte: 0x" TARGET_FMT_lx "\n", + __func__, pte_addr, pte); return TRANSLATE_FAIL; } if (!riscv_cpu_cfg(env)->ext_svnapot && (pte & PTE_N)) { + /* Reserved without Svnapot extension */ + qemu_log_mask(LOG_GUEST_ERROR, "%s: N bit set in PTE, " + "and Svnapot extension is disabled: " + "addr: 0x%" HWADDR_PRIx " pte: 0x" TARGET_FMT_lx "\n", + __func__, pte_addr, pte); return TRANSLATE_FAIL; } @@ -1002,14 +1408,19 @@ restart: /* Invalid PTE */ return TRANSLATE_FAIL; } + if (pte & (PTE_R | PTE_W | PTE_X)) { goto leaf; } - /* Inner PTE, continue walking */ if (pte & (PTE_D | PTE_A | PTE_U | PTE_ATTR)) { + /* D, A, and U bits are reserved in non-leaf/inner PTEs */ + qemu_log_mask(LOG_GUEST_ERROR, "%s: D, A, or U bits set in non-leaf PTE: " + "addr: 0x%" HWADDR_PRIx " pte: 0x" TARGET_FMT_lx "\n", + __func__, pte_addr, pte); return TRANSLATE_FAIL; } + /* Inner PTE, continue walking */ base = ppn << PGSHIFT; } @@ -1019,28 +1430,57 @@ restart: leaf: if (ppn & ((1ULL << ptshift) - 1)) { /* Misaligned PPN */ + qemu_log_mask(LOG_GUEST_ERROR, "%s: PPN bits in PTE is misaligned: " + "addr: 0x%" HWADDR_PRIx " pte: 0x" TARGET_FMT_lx "\n", + __func__, pte_addr, pte); return TRANSLATE_FAIL; } if (!pbmte && (pte & PTE_PBMT)) { /* Reserved without Svpbmt. */ + qemu_log_mask(LOG_GUEST_ERROR, "%s: PBMT bits set in PTE, " + "and Svpbmt extension is disabled: " + "addr: 0x%" HWADDR_PRIx " pte: 0x" TARGET_FMT_lx "\n", + __func__, pte_addr, pte); return TRANSLATE_FAIL; } + target_ulong rwx = pte & (PTE_R | PTE_W | PTE_X); /* Check for reserved combinations of RWX flags. */ - switch (pte & (PTE_R | PTE_W | PTE_X)) { - case PTE_W: + switch (rwx) { case PTE_W | PTE_X: return TRANSLATE_FAIL; + case PTE_W: + /* if bcfi enabled, PTE_W is not reserved and shadow stack page */ + if (cpu_get_bcfien(env) && first_stage) { + sstack_page = true; + /* + * if ss index, read and write allowed. else if not a probe + * then only read allowed + */ + rwx = is_sstack_idx ? (PTE_R | PTE_W) : (is_probe ? 0 : PTE_R); + break; + } + return TRANSLATE_FAIL; + case PTE_R: + /* + * no matter what's the `access_type`, shadow stack access to readonly + * memory are always store page faults. During unwind, loads will be + * promoted as store fault. + */ + if (is_sstack_idx) { + return TRANSLATE_FAIL; + } + break; } int prot = 0; - if (pte & PTE_R) { + if (rwx & PTE_R) { prot |= PAGE_READ; } - if (pte & PTE_W) { + if (rwx & PTE_W) { prot |= PAGE_WRITE; } - if (pte & PTE_X) { + if (rwx & PTE_X) { bool mxr = false; /* @@ -1084,8 +1524,11 @@ restart: } if (!((prot >> access_type) & 1)) { - /* Access check failed */ - return TRANSLATE_FAIL; + /* + * Access check failed, access check failures for shadow stack are + * access faults. + */ + return sstack_page ? TRANSLATE_PMP_FAIL : TRANSLATE_FAIL; } target_ulong updated_pte = pte; @@ -1116,24 +1559,23 @@ restart: * it is no longer valid and we must re-walk the page table. */ MemoryRegion *mr; - hwaddr l = sizeof(target_ulong), addr1; + hwaddr l = sxlen_bytes, addr1; mr = address_space_translate(cs->as, pte_addr, &addr1, &l, false, MEMTXATTRS_UNSPECIFIED); if (memory_region_is_ram(mr)) { target_ulong *pte_pa = qemu_map_ram_ptr(mr->ram_block, addr1); -#if TCG_OVERSIZED_GUEST - /* - * MTTCG is not enabled on oversized TCG guests so - * page table updates do not need to be atomic - */ - *pte_pa = pte = updated_pte; -#else - target_ulong old_pte = qatomic_cmpxchg(pte_pa, pte, updated_pte); + target_ulong old_pte; + if (riscv_cpu_sxl(env) == MXL_RV32) { + old_pte = qatomic_cmpxchg((uint32_t *)pte_pa, cpu_to_le32(pte), cpu_to_le32(updated_pte)); + old_pte = le32_to_cpu(old_pte); + } else { + old_pte = qatomic_cmpxchg(pte_pa, cpu_to_le64(pte), cpu_to_le64(updated_pte)); + old_pte = le64_to_cpu(old_pte); + } if (old_pte != pte) { goto restart; } pte = updated_pte; -#endif } else { /* * Misconfigured PTE in ROM (AD bits are not preset) or @@ -1223,13 +1665,13 @@ hwaddr riscv_cpu_get_phys_page_debug(CPUState *cs, vaddr addr) int mmu_idx = riscv_env_mmu_index(&cpu->env, false); if (get_physical_address(env, &phys_addr, &prot, addr, NULL, 0, mmu_idx, - true, env->virt_enabled, true)) { + true, env->virt_enabled, true, false)) { return -1; } if (env->virt_enabled) { if (get_physical_address(env, &phys_addr, &prot, phys_addr, NULL, - 0, MMUIdx_U, false, true, true)) { + 0, MMUIdx_U, false, true, true, false)) { return -1; } } @@ -1272,9 +1714,17 @@ void riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr, break; case MMU_DATA_LOAD: cs->exception_index = RISCV_EXCP_LOAD_ADDR_MIS; + /* shadow stack mis aligned accesses are access faults */ + if (mmu_idx & MMU_IDX_SS_WRITE) { + cs->exception_index = RISCV_EXCP_LOAD_ACCESS_FAULT; + } break; case MMU_DATA_STORE: cs->exception_index = RISCV_EXCP_STORE_AMO_ADDR_MIS; + /* shadow stack mis aligned accesses are access faults */ + if (mmu_idx & MMU_IDX_SS_WRITE) { + cs->exception_index = RISCV_EXCP_STORE_AMO_ACCESS_FAULT; + } break; default: g_assert_not_reached(); @@ -1323,7 +1773,7 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size, int ret = TRANSLATE_FAIL; int mode = mmuidx_priv(mmu_idx); /* default TLB page size */ - target_ulong tlb_size = TARGET_PAGE_SIZE; + hwaddr tlb_size = TARGET_PAGE_SIZE; env->guest_phys_fault_addr = 0; @@ -1335,7 +1785,7 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size, /* Two stage lookup */ ret = get_physical_address(env, &pa, &prot, address, &env->guest_phys_fault_addr, access_type, - mmu_idx, true, true, false); + mmu_idx, true, true, false, probe); /* * A G-stage exception may be triggered during two state lookup. @@ -1358,7 +1808,7 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size, ret = get_physical_address(env, &pa, &prot2, im_address, NULL, access_type, MMUIdx_U, false, true, - false); + false, probe); qemu_log_mask(CPU_LOG_MMU, "%s 2nd-stage address=%" VADDR_PRIx @@ -1375,7 +1825,7 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size, qemu_log_mask(CPU_LOG_MMU, "%s PMP address=" HWADDR_FMT_plx " ret %d prot" - " %d tlb_size " TARGET_FMT_lu "\n", + " %d tlb_size %" HWADDR_PRIu "\n", __func__, pa, ret, prot_pmp, tlb_size); prot &= prot_pmp; @@ -1395,7 +1845,8 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size, } else { /* Single stage lookup */ ret = get_physical_address(env, &pa, &prot, address, NULL, - access_type, mmu_idx, true, false, false); + access_type, mmu_idx, true, false, false, + probe); qemu_log_mask(CPU_LOG_MMU, "%s address=%" VADDR_PRIx " ret %d physical " @@ -1409,7 +1860,7 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size, qemu_log_mask(CPU_LOG_MMU, "%s PMP address=" HWADDR_FMT_plx " ret %d prot" - " %d tlb_size " TARGET_FMT_lu "\n", + " %d tlb_size %" HWADDR_PRIu "\n", __func__, pa, ret, prot_pmp, tlb_size); prot &= prot_pmp; @@ -1427,6 +1878,23 @@ bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size, } else if (probe) { return false; } else { + int wp_access = 0; + + if (access_type == MMU_DATA_LOAD) { + wp_access |= BP_MEM_READ; + } else if (access_type == MMU_DATA_STORE) { + wp_access |= BP_MEM_WRITE; + } + + /* + * If a watchpoint isn't found for 'addr' this will + * be a no-op and we'll resume the mmu_exception path. + * Otherwise we'll throw a debug exception and execution + * will continue elsewhere. + */ + cpu_check_watchpoint(cs, address, size, MEMTXATTRS_UNSPECIFIED, + wp_access, retaddr); + raise_mmu_exception(env, address, access_type, pmp_violation, first_stage_error, two_stage_lookup, two_stage_indirect_error); @@ -1641,6 +2109,40 @@ static target_ulong riscv_transformed_insn(CPURISCVState *env, return xinsn; } +static target_ulong promote_load_fault(target_ulong orig_cause) +{ + switch (orig_cause) { + case RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT: + return RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT; + + case RISCV_EXCP_LOAD_ACCESS_FAULT: + return RISCV_EXCP_STORE_AMO_ACCESS_FAULT; + + case RISCV_EXCP_LOAD_PAGE_FAULT: + return RISCV_EXCP_STORE_PAGE_FAULT; + } + + /* if no promotion, return original cause */ + return orig_cause; +} + +static void riscv_do_nmi(CPURISCVState *env, target_ulong cause, bool virt) +{ + env->mnstatus = set_field(env->mnstatus, MNSTATUS_NMIE, false); + env->mnstatus = set_field(env->mnstatus, MNSTATUS_MNPV, virt); + env->mnstatus = set_field(env->mnstatus, MNSTATUS_MNPP, env->priv); + env->mncause = cause; + env->mnepc = env->pc; + env->pc = env->rnmi_irqvec; + + if (cpu_get_fcfien(env)) { + env->mnstatus = set_field(env->mnstatus, MNSTATUS_MNPELP, env->elp); + } + + /* Trapping to M mode, virt is disabled */ + riscv_cpu_set_mode(env, PRV_M, false); +} + /* * Handle Traps * @@ -1653,7 +2155,10 @@ void riscv_cpu_do_interrupt(CPUState *cs) CPURISCVState *env = &cpu->env; bool virt = env->virt_enabled; bool write_gva = false; + bool always_storeamo = (env->excp_uw2 & RISCV_UW2_ALWAYS_STORE_AMO); + bool vsmode_exc; uint64_t s; + int mode; /* * cs->exception is 32-bits wide unlike mcause which is XLEN-bits wide @@ -1662,22 +2167,38 @@ void riscv_cpu_do_interrupt(CPUState *cs) bool async = !!(cs->exception_index & RISCV_EXCP_INT_FLAG); target_ulong cause = cs->exception_index & RISCV_EXCP_INT_MASK; uint64_t deleg = async ? env->mideleg : env->medeleg; - bool s_injected = env->mvip & (1 << cause) & env->mvien && - !(env->mip & (1 << cause)); - bool vs_injected = env->hvip & (1 << cause) & env->hvien && - !(env->mip & (1 << cause)); + bool s_injected = env->mvip & (1ULL << cause) & env->mvien && + !(env->mip & (1ULL << cause)); + bool vs_injected = env->hvip & (1ULL << cause) & env->hvien && + !(env->mip & (1ULL << cause)); + bool smode_double_trap = false; + uint64_t hdeleg = async ? env->hideleg : env->hedeleg; + const bool prev_virt = env->virt_enabled; + const target_ulong prev_priv = env->priv; target_ulong tval = 0; target_ulong tinst = 0; target_ulong htval = 0; target_ulong mtval2 = 0; + target_ulong src; + int sxlen = 0; + int mxlen = 16 << riscv_cpu_mxl(env); + bool nnmi_excep = false; + + if (cpu->cfg.ext_smrnmi && env->rnmip && async) { + riscv_do_nmi(env, cause | ((target_ulong)1U << (mxlen - 1)), + env->virt_enabled); + return; + } if (!async) { /* set tval to badaddr for traps with address information */ switch (cause) { +#ifdef CONFIG_TCG case RISCV_EXCP_SEMIHOST: do_common_semihosting(cs); env->pc += 4; return; +#endif case RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT: case RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT: case RISCV_EXCP_LOAD_ADDR_MIS: @@ -1686,6 +2207,9 @@ void riscv_cpu_do_interrupt(CPUState *cs) case RISCV_EXCP_STORE_AMO_ACCESS_FAULT: case RISCV_EXCP_LOAD_PAGE_FAULT: case RISCV_EXCP_STORE_PAGE_FAULT: + if (always_storeamo) { + cause = promote_load_fault(cause); + } write_gva = env->two_stage_lookup; tval = env->badaddr; if (env->two_stage_indirect_lookup) { @@ -1727,6 +2251,9 @@ void riscv_cpu_do_interrupt(CPUState *cs) cs->watchpoint_hit = NULL; } break; + case RISCV_EXCP_SW_CHECK: + tval = env->sw_check_code; + break; default: break; } @@ -1755,14 +2282,44 @@ void riscv_cpu_do_interrupt(CPUState *cs) __func__, env->mhartid, async, cause, env->pc, tval, riscv_cpu_get_trap_name(cause, async)); - if (env->priv <= PRV_S && cause < 64 && - (((deleg >> cause) & 1) || s_injected || vs_injected)) { - /* handle the trap in S-mode */ + mode = env->priv <= PRV_S && cause < 64 && + (((deleg >> cause) & 1) || s_injected || vs_injected) ? PRV_S : PRV_M; + + vsmode_exc = env->virt_enabled && cause < 64 && + (((hdeleg >> cause) & 1) || vs_injected); + + /* + * Check double trap condition only if already in S-mode and targeting + * S-mode + */ + if (cpu->cfg.ext_ssdbltrp && env->priv == PRV_S && mode == PRV_S) { + bool dte = (env->menvcfg & MENVCFG_DTE) != 0; + bool sdt = (env->mstatus & MSTATUS_SDT) != 0; + /* In VS or HS */ if (riscv_has_ext(env, RVH)) { - uint64_t hdeleg = async ? env->hideleg : env->hedeleg; + if (vsmode_exc) { + /* VS -> VS, use henvcfg instead of menvcfg*/ + dte = (env->henvcfg & HENVCFG_DTE) != 0; + } else if (env->virt_enabled) { + /* VS -> HS, use mstatus_hs */ + sdt = (env->mstatus_hs & MSTATUS_SDT) != 0; + } + } + smode_double_trap = dte && sdt; + if (smode_double_trap) { + mode = PRV_M; + } + } + + if (mode == PRV_S) { + /* handle the trap in S-mode */ + /* save elp status */ + if (cpu_get_fcfien(env)) { + env->mstatus = set_field(env->mstatus, MSTATUS_SPELP, env->elp); + } - if (env->virt_enabled && - (((hdeleg >> cause) & 1) || vs_injected)) { + if (riscv_has_ext(env, RVH)) { + if (vsmode_exc) { /* Trap to VS mode */ /* * See if we need to adjust cause. Yes if its VS mode interrupt @@ -1795,8 +2352,12 @@ void riscv_cpu_do_interrupt(CPUState *cs) s = set_field(s, MSTATUS_SPIE, get_field(s, MSTATUS_SIE)); s = set_field(s, MSTATUS_SPP, env->priv); s = set_field(s, MSTATUS_SIE, 0); + if (riscv_env_smode_dbltrp_enabled(env, virt)) { + s = set_field(s, MSTATUS_SDT, 1); + } env->mstatus = s; - env->scause = cause | ((target_ulong)async << (TARGET_LONG_BITS - 1)); + sxlen = 16 << riscv_cpu_sxl(env); + env->scause = cause | ((target_ulong)async << (sxlen - 1)); env->sepc = env->pc; env->stval = tval; env->htval = htval; @@ -1804,8 +2365,28 @@ void riscv_cpu_do_interrupt(CPUState *cs) env->pc = (env->stvec >> 2 << 2) + ((async && (env->stvec & 3) == 1) ? cause * 4 : 0); riscv_cpu_set_mode(env, PRV_S, virt); + + src = env->sepc; } else { + /* + * If the hart encounters an exception while executing in M-mode + * with the mnstatus.NMIE bit clear, the exception is an RNMI exception. + */ + nnmi_excep = cpu->cfg.ext_smrnmi && + !get_field(env->mnstatus, MNSTATUS_NMIE) && + !async; + /* handle the trap in M-mode */ + /* save elp status */ + if (cpu_get_fcfien(env)) { + if (nnmi_excep) { + env->mnstatus = set_field(env->mnstatus, MNSTATUS_MNPELP, + env->elp); + } else { + env->mstatus = set_field(env->mstatus, MSTATUS_MPELP, env->elp); + } + } + if (riscv_has_ext(env, RVH)) { if (env->virt_enabled) { riscv_cpu_swap_hypervisor_regs(env); @@ -1821,23 +2402,78 @@ void riscv_cpu_do_interrupt(CPUState *cs) /* Trapping to M mode, virt is disabled */ virt = false; } + /* + * If the hart encounters an exception while executing in M-mode, + * with the mnstatus.NMIE bit clear, the program counter is set to + * the RNMI exception trap handler address. + */ + nnmi_excep = cpu->cfg.ext_smrnmi && + !get_field(env->mnstatus, MNSTATUS_NMIE) && + !async; s = env->mstatus; s = set_field(s, MSTATUS_MPIE, get_field(s, MSTATUS_MIE)); s = set_field(s, MSTATUS_MPP, env->priv); s = set_field(s, MSTATUS_MIE, 0); + if (cpu->cfg.ext_smdbltrp) { + if (env->mstatus & MSTATUS_MDT) { + assert(env->priv == PRV_M); + if (!cpu->cfg.ext_smrnmi || nnmi_excep) { + cpu_abort(CPU(cpu), "M-mode double trap\n"); + } else { + riscv_do_nmi(env, cause, false); + return; + } + } + + s = set_field(s, MSTATUS_MDT, 1); + } env->mstatus = s; - env->mcause = cause | ~(((target_ulong)-1) >> async); + env->mcause = cause | ((target_ulong)async << (mxlen - 1)); + if (smode_double_trap) { + env->mtval2 = env->mcause; + env->mcause = RISCV_EXCP_DOUBLE_TRAP; + } else { + env->mtval2 = mtval2; + } env->mepc = env->pc; env->mtval = tval; - env->mtval2 = mtval2; env->mtinst = tinst; - env->pc = (env->mtvec >> 2 << 2) + - ((async && (env->mtvec & 3) == 1) ? cause * 4 : 0); + + /* + * For RNMI exception, program counter is set to the RNMI exception + * trap handler address. + */ + if (nnmi_excep) { + env->pc = env->rnmi_excpvec; + } else { + env->pc = (env->mtvec >> 2 << 2) + + ((async && (env->mtvec & 3) == 1) ? cause * 4 : 0); + } riscv_cpu_set_mode(env, PRV_M, virt); + src = env->mepc; + } + + if (riscv_cpu_cfg(env)->ext_smctr || riscv_cpu_cfg(env)->ext_ssctr) { + if (async && cause == IRQ_PMU_OVF) { + riscv_ctr_freeze(env, XCTRCTL_LCOFIFRZ, virt); + } else if (!async && cause == RISCV_EXCP_BREAKPOINT) { + riscv_ctr_freeze(env, XCTRCTL_BPFRZ, virt); + } + + riscv_ctr_add_entry(env, src, env->pc, + async ? CTRDATA_TYPE_INTERRUPT : CTRDATA_TYPE_EXCEPTION, + prev_priv, prev_virt); } /* + * Interrupt/exception/trap delivery is asynchronous event and as per + * zicfilp spec CPU should clear up the ELP state. No harm in clearing + * unconditionally. + */ + env->elp = false; + + /* * NOTE: it is not necessary to yield load reservations here. It is only * necessary for an SC from "another hart" to cause a load reservation * to be yielded. Refer to the memory consistency model section of the |