diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h index d68cb6e9e0..2170792ad7 100644 --- a/target/riscv/cpu.h +++ b/target/riscv/cpu.h @@ -547,6 +547,7 @@ void riscv_cpu_set_geilen(CPURISCVState *env, target_ulong geilen); bool riscv_cpu_vector_enabled(CPURISCVState *env); void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable); int riscv_env_mmu_index(CPURISCVState *env, bool ifetch); +bool cpu_get_fcfien(CPURISCVState *env); G_NORETURN void riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr, MMUAccessType access_type, int mmu_idx, uintptr_t retaddr); diff --git a/target/riscv/cpu_helper.c b/target/riscv/cpu_helper.c index 203c0a92ab..62f455dbd3 100644 --- a/target/riscv/cpu_helper.c +++ b/target/riscv/cpu_helper.c @@ -33,6 +33,7 @@ #include "cpu_bits.h" #include "debug.h" #include "tcg/oversized-guest.h" +#include "pmp.h" int riscv_env_mmu_index(CPURISCVState *env, bool ifetch) { @@ -63,6 +64,33 @@ int riscv_env_mmu_index(CPURISCVState *env, bool ifetch) #endif } +bool cpu_get_fcfien(CPURISCVState *env) +{ + /* no cfi extension, return false */ + if (!env_archcpu(env)->cfg.ext_zicfilp) { + return false; + } + + 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(); + } +} + void cpu_get_tb_cpu_state(CPURISCVState *env, vaddr *pc, uint64_t *cs_base, uint32_t *pflags) { @@ -546,6 +574,15 @@ 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 (current_virt) { @@ -1769,6 +1806,11 @@ void riscv_cpu_do_interrupt(CPUState *cs) if (env->priv <= PRV_S && cause < 64 && (((deleg >> cause) & 1) || s_injected || vs_injected)) { /* 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 (riscv_has_ext(env, RVH)) { uint64_t hdeleg = async ? env->hideleg : env->hedeleg; @@ -1818,6 +1860,11 @@ void riscv_cpu_do_interrupt(CPUState *cs) riscv_cpu_set_mode(env, PRV_S, virt); } else { /* handle the trap in M-mode */ + /* save elp status */ + if (cpu_get_fcfien(env)) { + 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); @@ -1850,6 +1897,13 @@ void riscv_cpu_do_interrupt(CPUState *cs) riscv_cpu_set_mode(env, PRV_M, 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 diff --git a/target/riscv/op_helper.c b/target/riscv/op_helper.c index 25a5263573..eddedacf4b 100644 --- a/target/riscv/op_helper.c +++ b/target/riscv/op_helper.c @@ -309,6 +309,15 @@ target_ulong helper_sret(CPURISCVState *env) riscv_cpu_set_mode(env, prev_priv, prev_virt); + /* + * If forward cfi enabled for new priv, restore elp status + * and clear spelp in mstatus + */ + if (cpu_get_fcfien(env)) { + env->elp = get_field(env->mstatus, MSTATUS_SPELP); + } + env->mstatus = set_field(env->mstatus, MSTATUS_SPELP, 0); + return retpc; } @@ -349,6 +358,14 @@ target_ulong helper_mret(CPURISCVState *env) } riscv_cpu_set_mode(env, prev_priv, prev_virt); + /* + * If forward cfi enabled for new priv, restore elp status + * and clear mpelp in mstatus + */ + if (cpu_get_fcfien(env)) { + env->elp = get_field(env->mstatus, MSTATUS_MPELP); + } + env->mstatus = set_field(env->mstatus, MSTATUS_MPELP, 0); return retpc; }