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Wed, 04 Dec 2024 04:51:38 -0800 (PST) Received: from [192.168.68.110] ([187.101.65.72]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-215a6fd6f57sm43344035ad.127.2024.12.04.04.51.35 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 04 Dec 2024 04:51:38 -0800 (PST) Message-ID: <30f0dc2d-b258-4cd7-98c3-d66718cb6fde@ventanamicro.com> Date: Wed, 4 Dec 2024 09:51:33 -0300 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v4 08/11] target/riscv: Add counter delegation/configuration support To: Atish Patra , qemu-riscv@nongnu.org, qemu-devel@nongnu.org Cc: kaiwenxue1@gmail.com, palmer@dabbelt.com, liwei1518@gmail.com, zhiwei_liu@linux.alibaba.com, bin.meng@windriver.com, alistair.francis@wdc.com, Kaiwen Xue References: <20241203-counter_delegation-v4-0-c12a89baed86@rivosinc.com> <20241203-counter_delegation-v4-8-c12a89baed86@rivosinc.com> Content-Language: en-US From: Daniel Henrique Barboza In-Reply-To: <20241203-counter_delegation-v4-8-c12a89baed86@rivosinc.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=2607:f8b0:4864:20::62c; envelope-from=dbarboza@ventanamicro.com; helo=mail-pl1-x62c.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-riscv@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-riscv-bounces+qemu-riscv=archiver.kernel.org@nongnu.org Sender: qemu-riscv-bounces+qemu-riscv=archiver.kernel.org@nongnu.org On 12/3/24 8:14 PM, Atish Patra wrote: > From: Kaiwen Xue > > The Smcdeleg/Ssccfg adds the support for counter delegation via > S*indcsr and Ssccfg. > > It also adds a new shadow CSR scountinhibit and menvcfg enable bit (CDE) > to enable this extension and scountovf virtualization. > > Signed-off-by: Kaiwen Xue > Co-developed-by: Atish Patra > Signed-off-by: Atish Patra > --- Reviewed-by: Daniel Henrique Barboza > target/riscv/csr.c | 304 ++++++++++++++++++++++++++++++++++++++++++++++++++--- > 1 file changed, 292 insertions(+), 12 deletions(-) > > diff --git a/target/riscv/csr.c b/target/riscv/csr.c > index 0985dbdca76d..a77b6ed4c9f3 100644 > --- a/target/riscv/csr.c > +++ b/target/riscv/csr.c > @@ -383,6 +383,21 @@ static RISCVException aia_smode32(CPURISCVState *env, int csrno) > return smode32(env, csrno); > } > > +static RISCVException scountinhibit_pred(CPURISCVState *env, int csrno) > +{ > + RISCVCPU *cpu = env_archcpu(env); > + > + if (!cpu->cfg.ext_ssccfg || !cpu->cfg.ext_smcdeleg) { > + return RISCV_EXCP_ILLEGAL_INST; > + } > + > + if (env->virt_enabled) { > + return RISCV_EXCP_VIRT_INSTRUCTION_FAULT; > + } > + > + return smode(env, csrno); > +} > + > static bool csrind_extensions_present(CPURISCVState *env) > { > return riscv_cpu_cfg(env)->ext_smcsrind || riscv_cpu_cfg(env)->ext_sscsrind; > @@ -1220,10 +1235,9 @@ done: > return result; > } > > -static RISCVException write_mhpmcounter(CPURISCVState *env, int csrno, > - target_ulong val) > +static RISCVException riscv_pmu_write_ctr(CPURISCVState *env, target_ulong val, > + uint32_t ctr_idx) > { > - int ctr_idx = csrno - CSR_MCYCLE; > PMUCTRState *counter = &env->pmu_ctrs[ctr_idx]; > uint64_t mhpmctr_val = val; > > @@ -1248,10 +1262,9 @@ static RISCVException write_mhpmcounter(CPURISCVState *env, int csrno, > return RISCV_EXCP_NONE; > } > > -static RISCVException write_mhpmcounterh(CPURISCVState *env, int csrno, > - target_ulong val) > +static RISCVException riscv_pmu_write_ctrh(CPURISCVState *env, target_ulong val, > + uint32_t ctr_idx) > { > - int ctr_idx = csrno - CSR_MCYCLEH; > PMUCTRState *counter = &env->pmu_ctrs[ctr_idx]; > uint64_t mhpmctr_val = counter->mhpmcounter_val; > uint64_t mhpmctrh_val = val; > @@ -1273,6 +1286,20 @@ static RISCVException write_mhpmcounterh(CPURISCVState *env, int csrno, > return RISCV_EXCP_NONE; > } > > +static int write_mhpmcounter(CPURISCVState *env, int csrno, target_ulong val) > +{ > + int ctr_idx = csrno - CSR_MCYCLE; > + > + return riscv_pmu_write_ctr(env, val, ctr_idx); > +} > + > +static int write_mhpmcounterh(CPURISCVState *env, int csrno, target_ulong val) > +{ > + int ctr_idx = csrno - CSR_MCYCLEH; > + > + return riscv_pmu_write_ctrh(env, val, ctr_idx); > +} > + > RISCVException riscv_pmu_read_ctr(CPURISCVState *env, target_ulong *val, > bool upper_half, uint32_t ctr_idx) > { > @@ -1338,6 +1365,167 @@ static RISCVException read_hpmcounterh(CPURISCVState *env, int csrno, > return riscv_pmu_read_ctr(env, val, true, ctr_index); > } > > +static int rmw_cd_mhpmcounter(CPURISCVState *env, int ctr_idx, > + target_ulong *val, target_ulong new_val, > + target_ulong wr_mask) > +{ > + if (wr_mask != 0 && wr_mask != -1) { > + return -EINVAL; > + } > + > + if (!wr_mask && val) { > + riscv_pmu_read_ctr(env, val, false, ctr_idx); > + } else if (wr_mask) { > + riscv_pmu_write_ctr(env, new_val, ctr_idx); > + } else { > + return -EINVAL; > + } > + > + return 0; > +} > + > +static int rmw_cd_mhpmcounterh(CPURISCVState *env, int ctr_idx, > + target_ulong *val, target_ulong new_val, > + target_ulong wr_mask) > +{ > + if (wr_mask != 0 && wr_mask != -1) { > + return -EINVAL; > + } > + > + if (!wr_mask && val) { > + riscv_pmu_read_ctr(env, val, true, ctr_idx); > + } else if (wr_mask) { > + riscv_pmu_write_ctrh(env, new_val, ctr_idx); > + } else { > + return -EINVAL; > + } > + > + return 0; > +} > + > +static int rmw_cd_mhpmevent(CPURISCVState *env, int evt_index, > + target_ulong *val, target_ulong new_val, > + target_ulong wr_mask) > +{ > + uint64_t mhpmevt_val = new_val; > + > + if (wr_mask != 0 && wr_mask != -1) { > + return -EINVAL; > + } > + > + if (!wr_mask && val) { > + *val = env->mhpmevent_val[evt_index]; > + if (riscv_cpu_cfg(env)->ext_sscofpmf) { > + *val &= ~MHPMEVENT_BIT_MINH; > + } > + } else if (wr_mask) { > + wr_mask &= ~MHPMEVENT_BIT_MINH; > + mhpmevt_val = (new_val & wr_mask) | > + (env->mhpmevent_val[evt_index] & ~wr_mask); > + if (riscv_cpu_mxl(env) == MXL_RV32) { > + mhpmevt_val = mhpmevt_val | > + ((uint64_t)env->mhpmeventh_val[evt_index] << 32); > + } > + env->mhpmevent_val[evt_index] = mhpmevt_val; > + riscv_pmu_update_event_map(env, mhpmevt_val, evt_index); > + } else { > + return -EINVAL; > + } > + > + return 0; > +} > + > +static int rmw_cd_mhpmeventh(CPURISCVState *env, int evt_index, > + target_ulong *val, target_ulong new_val, > + target_ulong wr_mask) > +{ > + uint64_t mhpmevth_val; > + uint64_t mhpmevt_val = env->mhpmevent_val[evt_index]; > + > + if (wr_mask != 0 && wr_mask != -1) { > + return -EINVAL; > + } > + > + if (!wr_mask && val) { > + *val = env->mhpmeventh_val[evt_index]; > + if (riscv_cpu_cfg(env)->ext_sscofpmf) { > + *val &= ~MHPMEVENTH_BIT_MINH; > + } > + } else if (wr_mask) { > + wr_mask &= ~MHPMEVENTH_BIT_MINH; > + env->mhpmeventh_val[evt_index] = > + (new_val & wr_mask) | (env->mhpmeventh_val[evt_index] & ~wr_mask); > + mhpmevth_val = env->mhpmeventh_val[evt_index]; > + mhpmevt_val = mhpmevt_val | (mhpmevth_val << 32); > + riscv_pmu_update_event_map(env, mhpmevt_val, evt_index); > + } else { > + return -EINVAL; > + } > + > + return 0; > +} > + > +static int rmw_cd_ctr_cfg(CPURISCVState *env, int cfg_index, target_ulong *val, > + target_ulong new_val, target_ulong wr_mask) > +{ > + switch (cfg_index) { > + case 0: /* CYCLECFG */ > + if (wr_mask) { > + wr_mask &= ~MCYCLECFG_BIT_MINH; > + env->mcyclecfg = (new_val & wr_mask) | (env->mcyclecfg & ~wr_mask); > + } else { > + *val = env->mcyclecfg &= ~MHPMEVENTH_BIT_MINH; > + } > + break; > + case 2: /* INSTRETCFG */ > + if (wr_mask) { > + wr_mask &= ~MINSTRETCFG_BIT_MINH; > + env->minstretcfg = (new_val & wr_mask) | > + (env->minstretcfg & ~wr_mask); > + } else { > + *val = env->minstretcfg &= ~MHPMEVENTH_BIT_MINH; > + } > + break; > + default: > + return -EINVAL; > + } > + return 0; > +} > + > +static int rmw_cd_ctr_cfgh(CPURISCVState *env, int cfg_index, target_ulong *val, > + target_ulong new_val, target_ulong wr_mask) > +{ > + > + if (riscv_cpu_mxl(env) != MXL_RV32) { > + return RISCV_EXCP_ILLEGAL_INST; > + } > + > + switch (cfg_index) { > + case 0: /* CYCLECFGH */ > + if (wr_mask) { > + wr_mask &= ~MCYCLECFGH_BIT_MINH; > + env->mcyclecfgh = (new_val & wr_mask) | > + (env->mcyclecfgh & ~wr_mask); > + } else { > + *val = env->mcyclecfgh; > + } > + break; > + case 2: /* INSTRETCFGH */ > + if (wr_mask) { > + wr_mask &= ~MINSTRETCFGH_BIT_MINH; > + env->minstretcfgh = (new_val & wr_mask) | > + (env->minstretcfgh & ~wr_mask); > + } else { > + *val = env->minstretcfgh; > + } > + break; > + default: > + return -EINVAL; > + } > + return 0; > +} > + > + > static RISCVException read_scountovf(CPURISCVState *env, int csrno, > target_ulong *val) > { > @@ -1347,6 +1535,14 @@ static RISCVException read_scountovf(CPURISCVState *env, int csrno, > target_ulong *mhpm_evt_val; > uint64_t of_bit_mask; > > + /* Virtualize scountovf for counter delegation */ > + if (riscv_cpu_cfg(env)->ext_sscofpmf && > + riscv_cpu_cfg(env)->ext_ssccfg && > + get_field(env->menvcfg, MENVCFG_CDE) && > + env->virt_enabled) { > + return RISCV_EXCP_VIRT_INSTRUCTION_FAULT; > + } > + > if (riscv_cpu_mxl(env) == MXL_RV32) { > mhpm_evt_val = env->mhpmeventh_val; > of_bit_mask = MHPMEVENTH_BIT_OF; > @@ -2290,11 +2486,72 @@ static int rmw_xireg_cd(CPURISCVState *env, int csrno, > target_ulong isel, target_ulong *val, > target_ulong new_val, target_ulong wr_mask) > { > - if (!riscv_cpu_cfg(env)->ext_smcdeleg) { > - return RISCV_EXCP_ILLEGAL_INST; > + int ret = -EINVAL; > + int ctr_index = isel - ISELECT_CD_FIRST; > + int isel_hpm_start = ISELECT_CD_FIRST + 3; > + > + if (!riscv_cpu_cfg(env)->ext_smcdeleg || !riscv_cpu_cfg(env)->ext_ssccfg) { > + ret = RISCV_EXCP_ILLEGAL_INST; > + goto done; > } > - /* TODO: Implement the functionality later */ > - return RISCV_EXCP_NONE; > + > + /* Invalid siselect value for reserved */ > + if (ctr_index == 1) { > + goto done; > + } > + > + /* sireg4 and sireg5 provides access RV32 only CSRs */ > + if (((csrno == CSR_SIREG5) || (csrno == CSR_SIREG4)) && > + (riscv_cpu_mxl(env) != MXL_RV32)) { > + ret = RISCV_EXCP_ILLEGAL_INST; > + goto done; > + } > + > + /* Check Sscofpmf dependancy */ > + if (!riscv_cpu_cfg(env)->ext_sscofpmf && csrno == CSR_SIREG5 && > + (isel_hpm_start <= isel && isel <= ISELECT_CD_LAST)) { > + goto done; > + } > + > + /* Check smcntrpmf dependancy */ > + if (!riscv_cpu_cfg(env)->ext_smcntrpmf && > + (csrno == CSR_SIREG2 || csrno == CSR_SIREG5) && > + (ISELECT_CD_FIRST <= isel && isel < isel_hpm_start)) { > + goto done; > + } > + > + if (!get_field(env->mcounteren, BIT(ctr_index)) || > + !get_field(env->menvcfg, MENVCFG_CDE)) { > + goto done; > + } > + > + switch (csrno) { > + case CSR_SIREG: > + ret = rmw_cd_mhpmcounter(env, ctr_index, val, new_val, wr_mask); > + break; > + case CSR_SIREG4: > + ret = rmw_cd_mhpmcounterh(env, ctr_index, val, new_val, wr_mask); > + break; > + case CSR_SIREG2: > + if (ctr_index <= 2) { > + ret = rmw_cd_ctr_cfg(env, ctr_index, val, new_val, wr_mask); > + } else { > + ret = rmw_cd_mhpmevent(env, ctr_index, val, new_val, wr_mask); > + } > + break; > + case CSR_SIREG5: > + if (ctr_index <= 2) { > + ret = rmw_cd_ctr_cfgh(env, ctr_index, val, new_val, wr_mask); > + } else { > + ret = rmw_cd_mhpmeventh(env, ctr_index, val, new_val, wr_mask); > + } > + break; > + default: > + goto done; > + } > + > +done: > + return ret; > } > > /* > @@ -2573,6 +2830,21 @@ static RISCVException write_mcountinhibit(CPURISCVState *env, int csrno, > return RISCV_EXCP_NONE; > } > > +static RISCVException read_scountinhibit(CPURISCVState *env, int csrno, > + target_ulong *val) > +{ > + /* S-mode can only access the bits delegated by M-mode */ > + *val = env->mcountinhibit & env->mcounteren; > + return RISCV_EXCP_NONE; > +} > + > +static RISCVException write_scountinhibit(CPURISCVState *env, int csrno, > + target_ulong val) > +{ > + write_mcountinhibit(env, csrno, val & env->mcounteren); > + return RISCV_EXCP_NONE; > +} > + > static RISCVException read_mcounteren(CPURISCVState *env, int csrno, > target_ulong *val) > { > @@ -2675,11 +2947,13 @@ static RISCVException write_menvcfg(CPURISCVState *env, int csrno, > target_ulong val) > { > const RISCVCPUConfig *cfg = riscv_cpu_cfg(env); > - uint64_t mask = MENVCFG_FIOM | MENVCFG_CBIE | MENVCFG_CBCFE | MENVCFG_CBZE; > + uint64_t mask = MENVCFG_FIOM | MENVCFG_CBIE | MENVCFG_CBCFE | > + MENVCFG_CBZE | MENVCFG_CDE; > > if (riscv_cpu_mxl(env) == MXL_RV64) { > mask |= (cfg->ext_svpbmt ? MENVCFG_PBMTE : 0) | > (cfg->ext_sstc ? MENVCFG_STCE : 0) | > + (cfg->ext_smcdeleg ? MENVCFG_CDE : 0) | > (cfg->ext_svadu ? MENVCFG_ADUE : 0); > > if (env_archcpu(env)->cfg.ext_zicfilp) { > @@ -2708,7 +2982,8 @@ static RISCVException write_menvcfgh(CPURISCVState *env, int csrno, > const RISCVCPUConfig *cfg = riscv_cpu_cfg(env); > uint64_t mask = (cfg->ext_svpbmt ? MENVCFG_PBMTE : 0) | > (cfg->ext_sstc ? MENVCFG_STCE : 0) | > - (cfg->ext_svadu ? MENVCFG_ADUE : 0); > + (cfg->ext_svadu ? MENVCFG_ADUE : 0) | > + (cfg->ext_smcdeleg ? MENVCFG_CDE : 0); > uint64_t valh = (uint64_t)val << 32; > > env->menvcfg = (env->menvcfg & ~mask) | (valh & mask); > @@ -5493,6 +5768,11 @@ riscv_csr_operations csr_ops[CSR_TABLE_SIZE] = { > write_sstateen_1_3, > .min_priv_ver = PRIV_VERSION_1_12_0 }, > > + /* Supervisor Counter Delegation */ > + [CSR_SCOUNTINHIBIT] = {"scountinhibit", scountinhibit_pred, > + read_scountinhibit, write_scountinhibit, > + .min_priv_ver = PRIV_VERSION_1_12_0 }, > + > /* Supervisor Trap Setup */ > [CSR_SSTATUS] = { "sstatus", smode, read_sstatus, write_sstatus, > NULL, read_sstatus_i128 }, >