/* * RISC-V CPU helpers for qemu. * * Copyright (c) 2016-2017 Sagar Karandikar, sagark@eecs.berkeley.edu * Copyright (c) 2017-2018 SiFive, Inc. * * This program is free software; you can redistribute it and/or modify it * under the terms and conditions of the GNU General Public License, * version 2 or later, as published by the Free Software Foundation. * * This program is distributed in the hope 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 . */ #include "qemu/osdep.h" #include "qemu/log.h" #include "qemu/main-loop.h" #include "cpu.h" #include "exec/exec-all.h" #include "tcg/tcg-op.h" #include "trace.h" #include "semihosting/common-semi.h" int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch) { #ifdef CONFIG_USER_ONLY return 0; #else return env->priv; #endif } void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc, target_ulong *cs_base, uint32_t *pflags) { CPUState *cs = env_cpu(env); RISCVCPU *cpu = RISCV_CPU(cs); uint32_t flags = 0; *pc = env->xl == MXL_RV32 ? env->pc & UINT32_MAX : env->pc; *cs_base = 0; if (riscv_has_ext(env, RVV) || cpu->cfg.ext_zve32f || cpu->cfg.ext_zve64f) { /* * 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. */ uint32_t vlmax = vext_get_vlmax(env_archcpu(env), env->vtype); uint32_t sew = FIELD_EX64(env->vtype, VTYPE, VSEW); uint32_t maxsz = vlmax << sew; 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, sew); 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); } else { flags = FIELD_DP32(flags, TB_FLAGS, VILL, 1); } #ifdef CONFIG_USER_ONLY flags |= TB_FLAGS_MSTATUS_FS; flags |= TB_FLAGS_MSTATUS_VS; #else flags |= cpu_mmu_index(env, 0); if (riscv_cpu_fp_enabled(env)) { flags |= env->mstatus & MSTATUS_FS; } if (riscv_cpu_vector_enabled(env)) { flags |= env->mstatus & MSTATUS_VS; } if (riscv_has_ext(env, RVH)) { if (env->priv == PRV_M || (env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) || (env->priv == PRV_U && !riscv_cpu_virt_enabled(env) && get_field(env->hstatus, HSTATUS_HU))) { flags = FIELD_DP32(flags, TB_FLAGS, HLSX, 1); } flags = FIELD_DP32(flags, TB_FLAGS, MSTATUS_HS_FS, get_field(env->mstatus_hs, MSTATUS_FS)); flags = FIELD_DP32(flags, TB_FLAGS, MSTATUS_HS_VS, get_field(env->mstatus_hs, MSTATUS_VS)); } #endif flags = FIELD_DP32(flags, TB_FLAGS, XL, env->xl); if (env->cur_pmmask < (env->xl == MXL_RV32 ? UINT32_MAX : UINT64_MAX)) { 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); } *pflags = flags; } void riscv_cpu_update_mask(CPURISCVState *env) { target_ulong mask = -1, base = 0; /* * TODO: Current RVJ spec does not specify * how the extension interacts with XLEN. */ #ifndef CONFIG_USER_ONLY if (riscv_has_ext(env, RVJ)) { switch (env->priv) { 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(); } } #endif if (env->xl == MXL_RV32) { env->cur_pmmask = mask & UINT32_MAX; env->cur_pmbase = base & UINT32_MAX; } else { env->cur_pmmask = mask; env->cur_pmbase = base; } } #ifndef CONFIG_USER_ONLY /* * The HS-mode is allowed to configure priority only for the * following VS-mode local interrupts: * * 0 (Reserved interrupt, reads as zero) * 1 Supervisor software interrupt * 4 (Reserved interrupt, reads as zero) * 5 Supervisor timer interrupt * 8 (Reserved interrupt, reads as zero) * 13 (Reserved interrupt) * 14 " * 15 " * 16 " * 18 Debug/trace interrupt * 20 (Reserved interrupt) * 22 " * 24 " * 26 " * 28 " * 30 (Reserved for standard reporting of bus or system errors) */ static const int hviprio_index2irq[] = { 0, 1, 4, 5, 8, 13, 14, 15, 16, 18, 20, 22, 24, 26, 28, 30 }; static const int hviprio_index2rdzero[] = { 1, 0, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }; int riscv_cpu_hviprio_index2irq(int index, int *out_irq, int *out_rdzero) { if (index < 0 || ARRAY_SIZE(hviprio_index2irq) <= index) { return -EINVAL; } if (out_irq) { *out_irq = hviprio_index2irq[index]; } if (out_rdzero) { *out_rdzero = hviprio_index2rdzero[index]; } return 0; } /* * Default priorities of local interrupts are defined in the * RISC-V Advanced Interrupt Architecture specification. * * ---------------------------------------------------------------- * Default | * Priority | Major Interrupt Numbers * ---------------------------------------------------------------- * Highest | 63 (3f), 62 (3e), 31 (1f), 30 (1e), 61 (3d), 60 (3c), * | 59 (3b), 58 (3a), 29 (1d), 28 (1c), 57 (39), 56 (38), * | 55 (37), 54 (36), 27 (1b), 26 (1a), 53 (35), 52 (34), * | 51 (33), 50 (32), 25 (19), 24 (18), 49 (31), 48 (30) * | * | 11 (0b), 3 (03), 7 (07) * | 9 (09), 1 (01), 5 (05) * | 12 (0c) * | 10 (0a), 2 (02), 6 (06) * | * | 47 (2f), 46 (2e), 23 (17), 22 (16), 45 (2d), 44 (2c), * | 43 (2b), 42 (2a), 21 (15), 20 (14), 41 (29), 40 (28), * | 39 (27), 38 (26), 19 (13), 18 (12), 37 (25), 36 (24), * Lowest | 35 (23), 34 (22), 17 (11), 16 (10), 33 (21), 32 (20) * ---------------------------------------------------------------- */ static const uint8_t default_iprio[64] = { [63] = IPRIO_DEFAULT_UPPER, [62] = IPRIO_DEFAULT_UPPER + 1, [31] = IPRIO_DEFAULT_UPPER + 2, [30] = IPRIO_DEFAULT_UPPER + 3, [61] = IPRIO_DEFAULT_UPPER + 4, [60] = IPRIO_DEFAULT_UPPER + 5, [59] = IPRIO_DEFAULT_UPPER + 6, [58] = IPRIO_DEFAULT_UPPER + 7, [29] = IPRIO_DEFAULT_UPPER + 8, [28] = IPRIO_DEFAULT_UPPER + 9, [57] = IPRIO_DEFAULT_UPPER + 10, [56] = IPRIO_DEFAULT_UPPER + 11, [55] = IPRIO_DEFAULT_UPPER + 12, [54] = IPRIO_DEFAULT_UPPER + 13, [27] = IPRIO_DEFAULT_UPPER + 14, [26] = IPRIO_DEFAULT_UPPER + 15, [53] = IPRIO_DEFAULT_UPPER + 16, [52] = IPRIO_DEFAULT_UPPER + 17, [51] = IPRIO_DEFAULT_UPPER + 18, [50] = IPRIO_DEFAULT_UPPER + 19, [25] = IPRIO_DEFAULT_UPPER + 20, [24] = IPRIO_DEFAULT_UPPER + 21, [49] = IPRIO_DEFAULT_UPPER + 22, [48] = IPRIO_DEFAULT_UPPER + 23, [11] = IPRIO_DEFAULT_M, [3] = IPRIO_DEFAULT_M + 1, [7] = IPRIO_DEFAULT_M + 2, [9] = IPRIO_DEFAULT_S, [1] = IPRIO_DEFAULT_S + 1, [5] = IPRIO_DEFAULT_S + 2, [12] = IPRIO_DEFAULT_SGEXT, [10] = IPRIO_DEFAULT_VS, [2] = IPRIO_DEFAULT_VS + 1, [6] = IPRIO_DEFAULT_VS + 2, [47] = IPRIO_DEFAULT_LOWER, [46] = IPRIO_DEFAULT_LOWER + 1, [23] = IPRIO_DEFAULT_LOWER + 2, [22] = IPRIO_DEFAULT_LOWER + 3, [45] = IPRIO_DEFAULT_LOWER + 4, [44] = IPRIO_DEFAULT_LOWER + 5, [43] = IPRIO_DEFAULT_LOWER + 6, [42] = IPRIO_DEFAULT_LOWER + 7, [21] = IPRIO_DEFAULT_LOWER + 8, [20] = IPRIO_DEFAULT_LOWER + 9, [41] = IPRIO_DEFAULT_LOWER + 10, [40] = IPRIO_DEFAULT_LOWER + 11, [39] = IPRIO_DEFAULT_LOWER + 12, [38] = IPRIO_DEFAULT_LOWER + 13, [19] = IPRIO_DEFAULT_LOWER + 14, [18] = IPRIO_DEFAULT_LOWER + 15, [37] = IPRIO_DEFAULT_LOWER + 16, [36] = IPRIO_DEFAULT_LOWER + 17, [35] = IPRIO_DEFAULT_LOWER + 18, [34] = IPRIO_DEFAULT_LOWER + 19, [17] = IPRIO_DEFAULT_LOWER + 20, [16] = IPRIO_DEFAULT_LOWER + 21, [33] = IPRIO_DEFAULT_LOWER + 22, [32] = IPRIO_DEFAULT_LOWER + 23, }; uint8_t riscv_cpu_default_priority(int irq) { if (irq < 0 || irq > 63) { return IPRIO_MMAXIPRIO; } return default_iprio[irq] ? default_iprio[irq] : IPRIO_MMAXIPRIO; }; static int riscv_cpu_pending_to_irq(CPURISCVState *env, int extirq, unsigned int extirq_def_prio, uint64_t pending, uint8_t *iprio) { int irq, best_irq = RISCV_EXCP_NONE; unsigned int prio, best_prio = UINT_MAX; if (!pending) { return RISCV_EXCP_NONE; } irq = ctz64(pending); if (!riscv_feature(env, RISCV_FEATURE_AIA)) { return irq; } pending = pending >> irq; while (pending) { prio = iprio[irq]; if (!prio) { if (irq == extirq) { prio = extirq_def_prio; } else { prio = (riscv_cpu_default_priority(irq) < extirq_def_prio) ? 1 : IPRIO_MMAXIPRIO; } } if ((pending & 0x1) && (prio <= best_prio)) { best_irq = irq; best_prio = prio; } irq++; pending = pending >> 1; } return best_irq; } static uint64_t riscv_cpu_all_pending(CPURISCVState *env) { uint32_t gein = get_field(env->hstatus, HSTATUS_VGEIN); uint64_t vsgein = (env->hgeip & (1ULL << gein)) ? MIP_VSEIP : 0; return (env->mip | vsgein) & env->mie; } int riscv_cpu_mirq_pending(CPURISCVState *env) { uint64_t irqs = riscv_cpu_all_pending(env) & ~env->mideleg & ~(MIP_SGEIP | MIP_VSSIP | MIP_VSTIP | MIP_VSEIP); return riscv_cpu_pending_to_irq(env, IRQ_M_EXT, IPRIO_DEFAULT_M, irqs, env->miprio); } int riscv_cpu_sirq_pending(CPURISCVState *env) { uint64_t irqs = riscv_cpu_all_pending(env) & env->mideleg & ~(MIP_VSSIP | MIP_VSTIP | MIP_VSEIP); return riscv_cpu_pending_to_irq(env, IRQ_S_EXT, IPRIO_DEFAULT_S, irqs, env->siprio); } int riscv_cpu_vsirq_pending(CPURISCVState *env) { uint64_t irqs = riscv_cpu_all_pending(env) & env->mideleg & (MIP_VSSIP | MIP_VSTIP | MIP_VSEIP); return riscv_cpu_pending_to_irq(env, IRQ_S_EXT, IPRIO_DEFAULT_S, irqs >> 1, env->hviprio); } static int riscv_cpu_local_irq_pending(CPURISCVState *env) { int virq; uint64_t irqs, pending, mie, hsie, vsie; /* Determine interrupt enable state of all privilege modes */ if (riscv_cpu_virt_enabled(env)) { mie = 1; hsie = 1; vsie = (env->priv < PRV_S) || (env->priv == PRV_S && get_field(env->mstatus, MSTATUS_SIE)); } else { mie = (env->priv < PRV_M) || (env->priv == PRV_M && get_field(env->mstatus, MSTATUS_MIE)); hsie = (env->priv < PRV_S) || (env->priv == PRV_S && get_field(env->mstatus, MSTATUS_SIE)); vsie = 0; } /* Determine all pending interrupts */ pending = riscv_cpu_all_pending(env); /* Check M-mode interrupts */ irqs = pending & ~env->mideleg & -mie; if (irqs) { return riscv_cpu_pending_to_irq(env, IRQ_M_EXT, IPRIO_DEFAULT_M, irqs, env->miprio); } /* Check HS-mode interrupts */ irqs = pending & env->mideleg & ~env->hideleg & -hsie; if (irqs) { return riscv_cpu_pending_to_irq(env, IRQ_S_EXT, IPRIO_DEFAULT_S, irqs, env->siprio); } /* Check VS-mode interrupts */ irqs = pending & env->mideleg & env->hideleg & -vsie; if (irqs) { virq = riscv_cpu_pending_to_irq(env, IRQ_S_EXT, IPRIO_DEFAULT_S, irqs >> 1, env->hviprio); return (virq <= 0) ? virq : virq + 1; } /* Indicate no pending interrupt */ return RISCV_EXCP_NONE; } bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request) { if (interrupt_request & CPU_INTERRUPT_HARD) { RISCVCPU *cpu = RISCV_CPU(cs); CPURISCVState *env = &cpu->env; int interruptno = riscv_cpu_local_irq_pending(env); if (interruptno >= 0) { cs->exception_index = RISCV_EXCP_INT_FLAG | interruptno; riscv_cpu_do_interrupt(cs); return true; } } return false; } /* Return true is floating point support is currently enabled */ bool riscv_cpu_fp_enabled(CPURISCVState *env) { if (env->mstatus & MSTATUS_FS) { if (riscv_cpu_virt_enabled(env) && !(env->mstatus_hs & MSTATUS_FS)) { return false; } return true; } return false; } /* Return true is vector support is currently enabled */ bool riscv_cpu_vector_enabled(CPURISCVState *env) { if (env->mstatus & MSTATUS_VS) { if (riscv_cpu_virt_enabled(env) && !(env->mstatus_hs & MSTATUS_VS)) { return false; } return true; } return false; } void riscv_cpu_swap_hypervisor_regs(CPURISCVState *env) { uint64_t mstatus_mask = MSTATUS_MXR | MSTATUS_SUM | MSTATUS_FS | MSTATUS_SPP | MSTATUS_SPIE | MSTATUS_SIE | MSTATUS64_UXL | MSTATUS_VS; bool current_virt = riscv_cpu_virt_enabled(env); g_assert(riscv_has_ext(env, RVH)); if (current_virt) { /* Current V=1 and we are about to change to V=0 */ env->vsstatus = env->mstatus & mstatus_mask; env->mstatus &= ~mstatus_mask; env->mstatus |= env->mstatus_hs; env->vstvec = env->stvec; env->stvec = env->stvec_hs; env->vsscratch = env->sscratch; env->sscratch = env->sscratch_hs; env->vsepc = env->sepc; env->sepc = env->sepc_hs; env->vscause = env->scause; env->scause = env->scause_hs; env->vstval = env->stval; env->stval = env->stval_hs; env->vsatp = env->satp; env->satp = env->satp_hs; } else { /* Current V=0 and we are about to change to V=1 */ env->mstatus_hs = env->mstatus & mstatus_mask; env->mstatus &= ~mstatus_mask; env->mstatus |= env->vsstatus; env->stvec_hs = env->stvec; env->stvec = env->vstvec; env->sscratch_hs = env->sscratch; env->sscratch = env->vsscratch; env->sepc_hs = env->sepc; env->sepc = env->vsepc; env->scause_hs = env->scause; env->scause = env->vscause; env->stval_hs = env->stval; env->stval = env->vstval; env->satp_hs = env->satp; env->satp = env->vsatp; } } target_ulong riscv_cpu_get_geilen(CPURISCVState *env) { if (!riscv_has_ext(env, RVH)) { return 0; } return env->geilen; } void riscv_cpu_set_geilen(CPURISCVState *env, target_ulong geilen) { if (!riscv_has_ext(env, RVH)) { return; } if (geilen > (TARGET_LONG_BITS - 1)) { return; } env->geilen = geilen; } bool riscv_cpu_virt_enabled(CPURISCVState *env) { if (!riscv_has_ext(env, RVH)) { return false; } return get_field(env->virt, VIRT_ONOFF); } void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable) { if (!riscv_has_ext(env, RVH)) { return; } /* Flush the TLB on all virt mode changes. */ if (get_field(env->virt, VIRT_ONOFF) != enable) { tlb_flush(env_cpu(env)); } env->virt = set_field(env->virt, VIRT_ONOFF, enable); if (enable) { /* * The guest external interrupts from an interrupt controller are * delivered only when the Guest/VM is running (i.e. V=1). This means * any guest external interrupt which is triggered while the Guest/VM * is not running (i.e. V=0) will be missed on QEMU resulting in guest * with sluggish response to serial console input and other I/O events. * * To solve this, we check and inject interrupt after setting V=1. */ riscv_cpu_update_mip(env_archcpu(env), 0, 0); } } bool riscv_cpu_two_stage_lookup(int mmu_idx) { return mmu_idx & TB_FLAGS_PRIV_HYP_ACCESS_MASK; } int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint64_t interrupts) { CPURISCVState *env = &cpu->env; if (env->miclaim & interrupts) { return -1; } else { env->miclaim |= interrupts; return 0; } } uint64_t riscv_cpu_update_mip(RISCVCPU *cpu, uint64_t mask, uint64_t value) { CPURISCVState *env = &cpu->env; CPUState *cs = CPU(cpu); uint64_t gein, vsgein = 0, old = env->mip; bool locked = false; if (riscv_cpu_virt_enabled(env)) { gein = get_field(env->hstatus, HSTATUS_VGEIN); vsgein = (env->hgeip & (1ULL << gein)) ? MIP_VSEIP : 0; } if (!qemu_mutex_iothread_locked()) { locked = true; qemu_mutex_lock_iothread(); } env->mip = (env->mip & ~mask) | (value & mask); if (env->mip | vsgein) { cpu_interrupt(cs, CPU_INTERRUPT_HARD); } else { cpu_reset_interrupt(cs, CPU_INTERRUPT_HARD); } if (locked) { qemu_mutex_unlock_iothread(); } return old; } void riscv_cpu_set_rdtime_fn(CPURISCVState *env, uint64_t (*fn)(uint32_t), uint32_t arg) { env->rdtime_fn = fn; env->rdtime_fn_arg = arg; } void riscv_cpu_set_aia_ireg_rmw_fn(CPURISCVState *env, uint32_t priv, int (*rmw_fn)(void *arg, target_ulong reg, target_ulong *val, target_ulong new_val, target_ulong write_mask), void *rmw_fn_arg) { if (priv <= PRV_M) { env->aia_ireg_rmw_fn[priv] = rmw_fn; env->aia_ireg_rmw_fn_arg[priv] = rmw_fn_arg; } } void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv) { if (newpriv > PRV_M) { g_assert_not_reached(); } if (newpriv == PRV_H) { newpriv = PRV_U; } /* 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 * context/process can be used by another, resulting in an SC succeeding * incorrectly. Version 2.2 of the ISA specification explicitly requires * this behaviour, while later revisions say that the kernel "should" use * an SC instruction to force the yielding of a load reservation on a * preemptive context switch. As a result, do both. */ env->load_res = -1; } /* * get_physical_address_pmp - check PMP permission for this physical address * * Match the PMP region and check permission for this physical address and it's * TLB page. Returns 0 if the permission checking was successful * * @env: CPURISCVState * @prot: The returned protection attributes * @tlb_size: TLB page size containing addr. It could be modified after PMP * permission checking. NULL if not set TLB page for addr. * @addr: The physical address to be checked permission * @access_type: The type of MMU access * @mode: Indicates current privilege level. */ static int get_physical_address_pmp(CPURISCVState *env, int *prot, target_ulong *tlb_size, hwaddr addr, int size, MMUAccessType access_type, int mode) { pmp_priv_t pmp_priv; target_ulong tlb_size_pmp = 0; if (!riscv_feature(env, RISCV_FEATURE_PMP)) { *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC; return TRANSLATE_SUCCESS; } if (!pmp_hart_has_privs(env, addr, size, 1 << access_type, &pmp_priv, mode)) { *prot = 0; return TRANSLATE_PMP_FAIL; } *prot = pmp_priv_to_page_prot(pmp_priv); if (tlb_size != NULL) { if (pmp_is_range_in_tlb(env, addr & ~(*tlb_size - 1), &tlb_size_pmp)) { *tlb_size = tlb_size_pmp; } } return TRANSLATE_SUCCESS; } /* get_physical_address - get the physical address for this virtual address * * Do a page table walk to obtain the physical address corresponding to a * virtual address. Returns 0 if the translation was successful * * Adapted from Spike's mmu_t::translate and mmu_t::walk * * @env: CPURISCVState * @physical: This will be set to the calculated physical address * @prot: The returned protection attributes * @addr: The virtual address to be translated * @fault_pte_addr: If not NULL, this will be set to fault pte address * when a error occurs on pte address translation. * This will already be shifted to match htval. * @access_type: The type of MMU access * @mmu_idx: Indicates current privilege level * @first_stage: Are we in first stage translation? * Second stage is used for hypervisor guest translation * @two_stage: Are we going to perform two stage translation * @is_debug: Is this access from a debugger or the monitor? */ static int get_physical_address(CPURISCVState *env, hwaddr *physical, int *prot, target_ulong addr, target_ulong *fault_pte_addr, int access_type, int mmu_idx, bool first_stage, bool two_stage, bool is_debug) { /* NOTE: the env->pc value visible here will not be * correct, but the value visible to the exception handler * (riscv_cpu_do_interrupt) is correct */ MemTxResult res; MemTxAttrs attrs = MEMTXATTRS_UNSPECIFIED; int mode = mmu_idx & TB_FLAGS_PRIV_MMU_MASK; bool use_background = false; hwaddr ppn; RISCVCPU *cpu = env_archcpu(env); /* * Check if we should use the background registers for the two * stage translation. We don't need to check if we actually need * two stage translation as that happened before this function * was called. Background registers will be used if the guest has * forced a two stage translation to be on (in HS or M mode). */ if (!riscv_cpu_virt_enabled(env) && two_stage) { use_background = true; } /* MPRV does not affect the virtual-machine load/store instructions, HLV, HLVX, and HSV. */ if (riscv_cpu_two_stage_lookup(mmu_idx)) { mode = get_field(env->hstatus, HSTATUS_SPVP); } else if (mode == PRV_M && access_type != MMU_INST_FETCH) { if (get_field(env->mstatus, MSTATUS_MPRV)) { mode = get_field(env->mstatus, MSTATUS_MPP); } } if (first_stage == false) { /* We are in stage 2 translation, this is similar to stage 1. */ /* Stage 2 is always taken as U-mode */ mode = PRV_U; } if (mode == PRV_M || !riscv_feature(env, RISCV_FEATURE_MMU)) { *physical = addr; *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC; return TRANSLATE_SUCCESS; } *prot = 0; hwaddr base; int levels, ptidxbits, ptesize, vm, sum, mxr, widened; if (first_stage == true) { mxr = get_field(env->mstatus, MSTATUS_MXR); } else { mxr = get_field(env->vsstatus, MSTATUS_MXR); } if (first_stage == true) { if (use_background) { if (riscv_cpu_mxl(env) == MXL_RV32) { base = (hwaddr)get_field(env->vsatp, SATP32_PPN) << PGSHIFT; vm = get_field(env->vsatp, SATP32_MODE); } else { base = (hwaddr)get_field(env->vsatp, SATP64_PPN) << PGSHIFT; vm = get_field(env->vsatp, SATP64_MODE); } } else { if (riscv_cpu_mxl(env) == MXL_RV32) { base = (hwaddr)get_field(env->satp, SATP32_PPN) << PGSHIFT; vm = get_field(env->satp, SATP32_MODE); } else { base = (hwaddr)get_field(env->satp, SATP64_PPN) << PGSHIFT; vm = get_field(env->satp, SATP64_MODE); } } widened = 0; } else { if (riscv_cpu_mxl(env) == MXL_RV32) { base = (hwaddr)get_field(env->hgatp, SATP32_PPN) << PGSHIFT; vm = get_field(env->hgatp, SATP32_MODE); } else { base = (hwaddr)get_field(env->hgatp, SATP64_PPN) << PGSHIFT; vm = get_field(env->hgatp, SATP64_MODE); } widened = 2; } /* status.SUM will be ignored if execute on background */ sum = get_field(env->mstatus, MSTATUS_SUM) || use_background || is_debug; switch (vm) { case VM_1_10_SV32: levels = 2; ptidxbits = 10; ptesize = 4; break; case VM_1_10_SV39: levels = 3; ptidxbits = 9; ptesize = 8; break; case VM_1_10_SV48: levels = 4; ptidxbits = 9; ptesize = 8; break; case VM_1_10_SV57: levels = 5; ptidxbits = 9; ptesize = 8; break; case VM_1_10_MBARE: *physical = addr; *prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC; return TRANSLATE_SUCCESS; default: g_assert_not_reached(); } CPUState *cs = env_cpu(env); int va_bits = PGSHIFT + levels * ptidxbits + widened; target_ulong mask, masked_msbs; if (TARGET_LONG_BITS > (va_bits - 1)) { mask = (1L << (TARGET_LONG_BITS - (va_bits - 1))) - 1; } else { mask = 0; } masked_msbs = (addr >> (va_bits - 1)) & mask; if (masked_msbs != 0 && masked_msbs != mask) { return TRANSLATE_FAIL; } int ptshift = (levels - 1) * ptidxbits; int i; #if !TCG_OVERSIZED_GUEST restart: #endif for (i = 0; i < levels; i++, ptshift -= ptidxbits) { target_ulong idx; if (i == 0) { idx = (addr >> (PGSHIFT + ptshift)) & ((1 << (ptidxbits + widened)) - 1); } else { idx = (addr >> (PGSHIFT + ptshift)) & ((1 << ptidxbits) - 1); } /* check that physical address of PTE is legal */ hwaddr pte_addr; if (two_stage && first_stage) { int vbase_prot; hwaddr vbase; /* Do the second stage translation on the base PTE address. */ int vbase_ret = get_physical_address(env, &vbase, &vbase_prot, base, NULL, MMU_DATA_LOAD, mmu_idx, false, true, is_debug); if (vbase_ret != TRANSLATE_SUCCESS) { if (fault_pte_addr) { *fault_pte_addr = (base + idx * ptesize) >> 2; } return TRANSLATE_G_STAGE_FAIL; } pte_addr = vbase + idx * ptesize; } else { pte_addr = base + idx * ptesize; } int pmp_prot; int pmp_ret = get_physical_address_pmp(env, &pmp_prot, NULL, pte_addr, sizeof(target_ulong), MMU_DATA_LOAD, PRV_S); if (pmp_ret != TRANSLATE_SUCCESS) { return TRANSLATE_PMP_FAIL; } target_ulong pte; if (riscv_cpu_mxl(env) == MXL_RV32) { pte = address_space_ldl(cs->as, pte_addr, attrs, &res); } else { pte = address_space_ldq(cs->as, pte_addr, attrs, &res); } if (res != MEMTX_OK) { return TRANSLATE_FAIL; } if (riscv_cpu_sxl(env) == MXL_RV32) { ppn = pte >> PTE_PPN_SHIFT; } else if (cpu->cfg.ext_svpbmt || cpu->cfg.ext_svnapot) { ppn = (pte & (target_ulong)PTE_PPN_MASK) >> PTE_PPN_SHIFT; } else { ppn = pte >> PTE_PPN_SHIFT; if ((pte & ~(target_ulong)PTE_PPN_MASK) >> PTE_PPN_SHIFT) { return TRANSLATE_FAIL; } } if (!(pte & PTE_V)) { /* Invalid PTE */ return TRANSLATE_FAIL; } else if (!(pte & (PTE_R | PTE_W | PTE_X))) { /* Inner PTE, continue walking */ if (pte & (PTE_D | PTE_A | PTE_U)) { return TRANSLATE_FAIL; } base = ppn << PGSHIFT; } else if ((pte & (PTE_R | PTE_W | PTE_X)) == PTE_W) { /* Reserved leaf PTE flags: PTE_W */ return TRANSLATE_FAIL; } else if ((pte & (PTE_R | PTE_W | PTE_X)) == (PTE_W | PTE_X)) { /* Reserved leaf PTE flags: PTE_W + PTE_X */ return TRANSLATE_FAIL; } else if ((pte & PTE_U) && ((mode != PRV_U) && (!sum || access_type == MMU_INST_FETCH))) { /* User PTE flags when not U mode and mstatus.SUM is not set, or the access type is an instruction fetch */ return TRANSLATE_FAIL; } else if (!(pte & PTE_U) && (mode != PRV_S)) { /* Supervisor PTE flags when not S mode */ return TRANSLATE_FAIL; } else if (ppn & ((1ULL << ptshift) - 1)) { /* Misaligned PPN */ return TRANSLATE_FAIL; } else if (access_type == MMU_DATA_LOAD && !((pte & PTE_R) || ((pte & PTE_X) && mxr))) { /* Read access check failed */ return TRANSLATE_FAIL; } else if (access_type == MMU_DATA_STORE && !(pte & PTE_W)) { /* Write access check failed */ return TRANSLATE_FAIL; } else if (access_type == MMU_INST_FETCH && !(pte & PTE_X)) { /* Fetch access check failed */ return TRANSLATE_FAIL; } else { /* if necessary, set accessed and dirty bits. */ target_ulong updated_pte = pte | PTE_A | (access_type == MMU_DATA_STORE ? PTE_D : 0); /* Page table updates need to be atomic with MTTCG enabled */ if (updated_pte != pte) { /* * - if accessed or dirty bits need updating, and the PTE is * in RAM, then we do so atomically with a compare and swap. * - if the PTE is in IO space or ROM, then it can't be updated * and we return TRANSLATE_FAIL. * - if the PTE changed by the time we went to update it, then * it is no longer valid and we must re-walk the page table. */ MemoryRegion *mr; hwaddr l = sizeof(target_ulong), 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); if (old_pte != pte) { goto restart; } else { pte = updated_pte; } #endif } else { /* misconfigured PTE in ROM (AD bits are not preset) or * PTE is in IO space and can't be updated atomically */ return TRANSLATE_FAIL; } } /* for superpage mappings, make a fake leaf PTE for the TLB's benefit. */ target_ulong vpn = addr >> PGSHIFT; *physical = ((ppn | (vpn & ((1L << ptshift) - 1))) << PGSHIFT) | (addr & ~TARGET_PAGE_MASK); /* set permissions on the TLB entry */ if ((pte & PTE_R) || ((pte & PTE_X) && mxr)) { *prot |= PAGE_READ; } if ((pte & PTE_X)) { *prot |= PAGE_EXEC; } /* add write permission on stores or if the page is already dirty, so that we TLB miss on later writes to update the dirty bit */ if ((pte & PTE_W) && (access_type == MMU_DATA_STORE || (pte & PTE_D))) { *prot |= PAGE_WRITE; } return TRANSLATE_SUCCESS; } } return TRANSLATE_FAIL; } static void raise_mmu_exception(CPURISCVState *env, target_ulong address, MMUAccessType access_type, bool pmp_violation, bool first_stage, bool two_stage) { CPUState *cs = env_cpu(env); int page_fault_exceptions, vm; uint64_t stap_mode; if (riscv_cpu_mxl(env) == MXL_RV32) { stap_mode = SATP32_MODE; } else { stap_mode = SATP64_MODE; } if (first_stage) { vm = get_field(env->satp, stap_mode); } else { vm = get_field(env->hgatp, stap_mode); } page_fault_exceptions = vm != VM_1_10_MBARE && !pmp_violation; switch (access_type) { case MMU_INST_FETCH: if (riscv_cpu_virt_enabled(env) && !first_stage) { cs->exception_index = RISCV_EXCP_INST_GUEST_PAGE_FAULT; } else { cs->exception_index = page_fault_exceptions ? RISCV_EXCP_INST_PAGE_FAULT : RISCV_EXCP_INST_ACCESS_FAULT; } break; case MMU_DATA_LOAD: if (two_stage && !first_stage) { cs->exception_index = RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT; } else { cs->exception_index = page_fault_exceptions ? RISCV_EXCP_LOAD_PAGE_FAULT : RISCV_EXCP_LOAD_ACCESS_FAULT; } break; case MMU_DATA_STORE: if (two_stage && !first_stage) { cs->exception_index = RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT; } else { cs->exception_index = page_fault_exceptions ? RISCV_EXCP_STORE_PAGE_FAULT : RISCV_EXCP_STORE_AMO_ACCESS_FAULT; } break; default: g_assert_not_reached(); } env->badaddr = address; env->two_stage_lookup = two_stage; } hwaddr riscv_cpu_get_phys_page_debug(CPUState *cs, vaddr addr) { RISCVCPU *cpu = RISCV_CPU(cs); CPURISCVState *env = &cpu->env; hwaddr phys_addr; int prot; int mmu_idx = cpu_mmu_index(&cpu->env, false); if (get_physical_address(env, &phys_addr, &prot, addr, NULL, 0, mmu_idx, true, riscv_cpu_virt_enabled(env), true)) { return -1; } if (riscv_cpu_virt_enabled(env)) { if (get_physical_address(env, &phys_addr, &prot, phys_addr, NULL, 0, mmu_idx, false, true, true)) { return -1; } } return phys_addr & TARGET_PAGE_MASK; } void riscv_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) { RISCVCPU *cpu = RISCV_CPU(cs); CPURISCVState *env = &cpu->env; if (access_type == MMU_DATA_STORE) { cs->exception_index = RISCV_EXCP_STORE_AMO_ACCESS_FAULT; } else if (access_type == MMU_DATA_LOAD) { cs->exception_index = RISCV_EXCP_LOAD_ACCESS_FAULT; } else { cs->exception_index = RISCV_EXCP_INST_ACCESS_FAULT; } env->badaddr = addr; env->two_stage_lookup = riscv_cpu_virt_enabled(env) || riscv_cpu_two_stage_lookup(mmu_idx); riscv_raise_exception(&cpu->env, cs->exception_index, retaddr); } void riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr, MMUAccessType access_type, int mmu_idx, uintptr_t retaddr) { RISCVCPU *cpu = RISCV_CPU(cs); CPURISCVState *env = &cpu->env; switch (access_type) { case MMU_INST_FETCH: cs->exception_index = RISCV_EXCP_INST_ADDR_MIS; break; case MMU_DATA_LOAD: cs->exception_index = RISCV_EXCP_LOAD_ADDR_MIS; break; case MMU_DATA_STORE: cs->exception_index = RISCV_EXCP_STORE_AMO_ADDR_MIS; break; default: g_assert_not_reached(); } env->badaddr = addr; env->two_stage_lookup = riscv_cpu_virt_enabled(env) || riscv_cpu_two_stage_lookup(mmu_idx); riscv_raise_exception(env, cs->exception_index, retaddr); } bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size, MMUAccessType access_type, int mmu_idx, bool probe, uintptr_t retaddr) { RISCVCPU *cpu = RISCV_CPU(cs); CPURISCVState *env = &cpu->env; vaddr im_address; hwaddr pa = 0; int prot, prot2, prot_pmp; bool pmp_violation = false; bool first_stage_error = true; bool two_stage_lookup = false; int ret = TRANSLATE_FAIL; int mode = mmu_idx; /* default TLB page size */ target_ulong tlb_size = TARGET_PAGE_SIZE; env->guest_phys_fault_addr = 0; qemu_log_mask(CPU_LOG_MMU, "%s ad %" VADDR_PRIx " rw %d mmu_idx %d\n", __func__, address, access_type, mmu_idx); /* MPRV does not affect the virtual-machine load/store instructions, HLV, HLVX, and HSV. */ if (riscv_cpu_two_stage_lookup(mmu_idx)) { mode = get_field(env->hstatus, HSTATUS_SPVP); } else if (mode == PRV_M && access_type != MMU_INST_FETCH && get_field(env->mstatus, MSTATUS_MPRV)) { mode = get_field(env->mstatus, MSTATUS_MPP); if (riscv_has_ext(env, RVH) && get_field(env->mstatus, MSTATUS_MPV)) { two_stage_lookup = true; } } if (riscv_cpu_virt_enabled(env) || ((riscv_cpu_two_stage_lookup(mmu_idx) || two_stage_lookup) && access_type != MMU_INST_FETCH)) { /* Two stage lookup */ ret = get_physical_address(env, &pa, &prot, address, &env->guest_phys_fault_addr, access_type, mmu_idx, true, true, false); /* * A G-stage exception may be triggered during two state lookup. * And the env->guest_phys_fault_addr has already been set in * get_physical_address(). */ if (ret == TRANSLATE_G_STAGE_FAIL) { first_stage_error = false; access_type = MMU_DATA_LOAD; } qemu_log_mask(CPU_LOG_MMU, "%s 1st-stage address=%" VADDR_PRIx " ret %d physical " TARGET_FMT_plx " prot %d\n", __func__, address, ret, pa, prot); if (ret == TRANSLATE_SUCCESS) { /* Second stage lookup */ im_address = pa; ret = get_physical_address(env, &pa, &prot2, im_address, NULL, access_type, mmu_idx, false, true, false); qemu_log_mask(CPU_LOG_MMU, "%s 2nd-stage address=%" VADDR_PRIx " ret %d physical " TARGET_FMT_plx " prot %d\n", __func__, im_address, ret, pa, prot2); prot &= prot2; if (ret == TRANSLATE_SUCCESS) { ret = get_physical_address_pmp(env, &prot_pmp, &tlb_size, pa, size, access_type, mode); qemu_log_mask(CPU_LOG_MMU, "%s PMP address=" TARGET_FMT_plx " ret %d prot" " %d tlb_size " TARGET_FMT_lu "\n", __func__, pa, ret, prot_pmp, tlb_size); prot &= prot_pmp; } if (ret != TRANSLATE_SUCCESS) { /* * Guest physical address translation failed, this is a HS * level exception */ first_stage_error = false; env->guest_phys_fault_addr = (im_address | (address & (TARGET_PAGE_SIZE - 1))) >> 2; } } } else { /* Single stage lookup */ ret = get_physical_address(env, &pa, &prot, address, NULL, access_type, mmu_idx, true, false, false); qemu_log_mask(CPU_LOG_MMU, "%s address=%" VADDR_PRIx " ret %d physical " TARGET_FMT_plx " prot %d\n", __func__, address, ret, pa, prot); if (ret == TRANSLATE_SUCCESS) { ret = get_physical_address_pmp(env, &prot_pmp, &tlb_size, pa, size, access_type, mode); qemu_log_mask(CPU_LOG_MMU, "%s PMP address=" TARGET_FMT_plx " ret %d prot" " %d tlb_size " TARGET_FMT_lu "\n", __func__, pa, ret, prot_pmp, tlb_size); prot &= prot_pmp; } } if (ret == TRANSLATE_PMP_FAIL) { pmp_violation = true; } if (ret == TRANSLATE_SUCCESS) { tlb_set_page(cs, address & ~(tlb_size - 1), pa & ~(tlb_size - 1), prot, mmu_idx, tlb_size); return true; } else if (probe) { return false; } else { raise_mmu_exception(env, address, access_type, pmp_violation, first_stage_error, riscv_cpu_virt_enabled(env) || riscv_cpu_two_stage_lookup(mmu_idx)); riscv_raise_exception(env, cs->exception_index, retaddr); } return true; } #endif /* !CONFIG_USER_ONLY */ /* * Handle Traps * * Adapted from Spike's processor_t::take_trap. * */ void riscv_cpu_do_interrupt(CPUState *cs) { #if !defined(CONFIG_USER_ONLY) RISCVCPU *cpu = RISCV_CPU(cs); CPURISCVState *env = &cpu->env; bool write_gva = false; uint64_t s; /* cs->exception is 32-bits wide unlike mcause which is XLEN-bits wide * so we mask off the MSB and separate into trap type and cause. */ 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; target_ulong tval = 0; target_ulong htval = 0; target_ulong mtval2 = 0; if (cause == RISCV_EXCP_SEMIHOST) { if (env->priv >= PRV_S) { env->gpr[xA0] = do_common_semihosting(cs); env->pc += 4; return; } cause = RISCV_EXCP_BREAKPOINT; } if (!async) { /* set tval to badaddr for traps with address information */ switch (cause) { case RISCV_EXCP_INST_GUEST_PAGE_FAULT: case RISCV_EXCP_LOAD_GUEST_ACCESS_FAULT: case RISCV_EXCP_STORE_GUEST_AMO_ACCESS_FAULT: case RISCV_EXCP_INST_ADDR_MIS: case RISCV_EXCP_INST_ACCESS_FAULT: case RISCV_EXCP_LOAD_ADDR_MIS: case RISCV_EXCP_STORE_AMO_ADDR_MIS: case RISCV_EXCP_LOAD_ACCESS_FAULT: case RISCV_EXCP_STORE_AMO_ACCESS_FAULT: case RISCV_EXCP_INST_PAGE_FAULT: case RISCV_EXCP_LOAD_PAGE_FAULT: case RISCV_EXCP_STORE_PAGE_FAULT: write_gva = true; tval = env->badaddr; break; case RISCV_EXCP_ILLEGAL_INST: tval = env->bins; break; default: break; } /* ecall is dispatched as one cause so translate based on mode */ if (cause == RISCV_EXCP_U_ECALL) { assert(env->priv <= 3); if (env->priv == PRV_M) { cause = RISCV_EXCP_M_ECALL; } else if (env->priv == PRV_S && riscv_cpu_virt_enabled(env)) { cause = RISCV_EXCP_VS_ECALL; } else if (env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) { cause = RISCV_EXCP_S_ECALL; } else if (env->priv == PRV_U) { cause = RISCV_EXCP_U_ECALL; } } } trace_riscv_trap(env->mhartid, async, cause, env->pc, tval, riscv_cpu_get_trap_name(cause, async)); qemu_log_mask(CPU_LOG_INT, "%s: hart:"TARGET_FMT_ld", async:%d, cause:"TARGET_FMT_lx", " "epc:0x"TARGET_FMT_lx", tval:0x"TARGET_FMT_lx", desc=%s\n", __func__, env->mhartid, async, cause, env->pc, tval, riscv_cpu_get_trap_name(cause, async)); if (env->priv <= PRV_S && cause < TARGET_LONG_BITS && ((deleg >> cause) & 1)) { /* handle the trap in S-mode */ if (riscv_has_ext(env, RVH)) { uint64_t hdeleg = async ? env->hideleg : env->hedeleg; if (riscv_cpu_virt_enabled(env) && ((hdeleg >> cause) & 1)) { /* Trap to VS mode */ /* * See if we need to adjust cause. Yes if its VS mode interrupt * no if hypervisor has delegated one of hs mode's interrupt */ if (cause == IRQ_VS_TIMER || cause == IRQ_VS_SOFT || cause == IRQ_VS_EXT) { cause = cause - 1; } write_gva = false; } else if (riscv_cpu_virt_enabled(env)) { /* Trap into HS mode, from virt */ riscv_cpu_swap_hypervisor_regs(env); env->hstatus = set_field(env->hstatus, HSTATUS_SPVP, env->priv); env->hstatus = set_field(env->hstatus, HSTATUS_SPV, riscv_cpu_virt_enabled(env)); htval = env->guest_phys_fault_addr; riscv_cpu_set_virt_enabled(env, 0); } else { /* Trap into HS mode */ env->hstatus = set_field(env->hstatus, HSTATUS_SPV, false); htval = env->guest_phys_fault_addr; write_gva = false; } env->hstatus = set_field(env->hstatus, HSTATUS_GVA, write_gva); } s = env->mstatus; 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); env->mstatus = s; env->scause = cause | ((target_ulong)async << (TARGET_LONG_BITS - 1)); env->sepc = env->pc; env->stval = tval; env->htval = htval; env->pc = (env->stvec >> 2 << 2) + ((async && (env->stvec & 3) == 1) ? cause * 4 : 0); riscv_cpu_set_mode(env, PRV_S); } else { /* handle the trap in M-mode */ if (riscv_has_ext(env, RVH)) { if (riscv_cpu_virt_enabled(env)) { riscv_cpu_swap_hypervisor_regs(env); } env->mstatus = set_field(env->mstatus, MSTATUS_MPV, riscv_cpu_virt_enabled(env)); if (riscv_cpu_virt_enabled(env) && tval) { env->mstatus = set_field(env->mstatus, MSTATUS_GVA, 1); } mtval2 = env->guest_phys_fault_addr; /* Trapping to M mode, virt is disabled */ riscv_cpu_set_virt_enabled(env, 0); } 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); env->mstatus = s; env->mcause = cause | ~(((target_ulong)-1) >> async); env->mepc = env->pc; env->mtval = tval; env->mtval2 = mtval2; env->pc = (env->mtvec >> 2 << 2) + ((async && (env->mtvec & 3) == 1) ? cause * 4 : 0); riscv_cpu_set_mode(env, PRV_M); } /* 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 * RISC-V ISA Specification. */ env->two_stage_lookup = false; #endif cs->exception_index = RISCV_EXCP_NONE; /* mark handled to qemu */ }