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[2001:8b0:1d0::2]) by smtp.gmail.com with ESMTPSA id d11-20020a5d6dcb000000b0020e6ce4dabdsm9754335wrz.103.2022.06.27.03.22.52 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 27 Jun 2022 03:22:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:subject:date:message-id:in-reply-to:references:mime-version :content-transfer-encoding; bh=S5KlS03XVlUTJnKwjh9r15WOZqJ50ROAGOtbVW9mWeY=; b=ECh2yd0JL7PvbvW9gxi9g3kvrgUUqoOrULEsJ1aCsXxoHekbNJ2c8PT5ILvIhckkAs 7vgH85LiGHLeuLZJoYE1J264fMpsUwkTIuhPZE12hImc0IBdVpFuc3cGc962l8s61+ZD z5WD5+D33jKJynGlGkhuZeim1RrOeUf2Pbx4VwGbyM5LguKQDe7OxV/yBY6sG68LYLVG gQq2qUHEoVPKIXuKTtn9Ds1ZDBuEPBuzKWPjcnFp9s6A3dwnP5fmABhzknUGxMF8cY/l Lj2SCQ5TkPh1B+siq/6AaPF5jRqnO5GUQCNNRkJ/aIWOfk+rU1RO19v3YvrcyzEXrrCf BJvg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=S5KlS03XVlUTJnKwjh9r15WOZqJ50ROAGOtbVW9mWeY=; b=e3Af0i9dBGhhGHUn0XPJglGZ9mehMdhq98yiI3zT+RvphMIA88rR5XgX5/KVUK9oQn TqT05vh1h8yY7cUdJ1Qxap1I1htGqLGvrTCMVZXuMIM8Rv7N2vSFCFtCmYaQN3x7r6D1 x8oSBBH6MLNPw//X/rwgEI/sXL9R1H0N27YKShlqmmdY2Q1sNwlpXmmpwIzkj1Nt5xb/ agoiTx40d0whyLR2JjoWuLCNqM+TMSU/uICNoWbNXjzqG3Ur6RdHn+dF9H5fV6PBVU0x zCtoLuQjewRCeBO4TSXr7YovflDHW4b1PbX57YuYI1DtlVm+NtFXbLHHGs3bl5rzApmU H+Pw== X-Gm-Message-State: AJIora+58M+PNhqqBlxJFtOkZgtp+beTHjgUGdAreOTN15tsCSUpkiDt ddBG1a0l8uqyuJ1E38smx9wCrgKedBHEFw== X-Google-Smtp-Source: AGRyM1v2xWPKQ6ZtkpHLK3xbpJ3KkSoAI7sEXcywJbr5+yA0rYIQZpiq/HkMjB0fyE0kGy/6ZJ9N9w== X-Received: by 2002:a05:6000:2ab:b0:211:7fd6:24ef with SMTP id l11-20020a05600002ab00b002117fd624efmr11706448wry.67.1656325373301; Mon, 27 Jun 2022 03:22:53 -0700 (PDT) From: Peter Maydell To: qemu-devel@nongnu.org Subject: [PULL 20/25] target/arm: Add cpu properties for SME Date: Mon, 27 Jun 2022 11:22:31 +0100 Message-Id: <20220627102236.3097629-21-peter.maydell@linaro.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220627102236.3097629-1-peter.maydell@linaro.org> References: <20220627102236.3097629-1-peter.maydell@linaro.org> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=2a00:1450:4864:20::42c; envelope-from=peter.maydell@linaro.org; helo=mail-wr1-x42c.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, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@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-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: pass (identity @linaro.org) X-ZM-MESSAGEID: 1656326684176100001 Content-Type: text/plain; charset="utf-8" From: Richard Henderson Mirror the properties for SVE. The main difference is that any arbitrary set of powers of 2 may be supported, and not the stricter constraints that apply to SVE. Include a property to control FEAT_SME_FA64, as failing to restrict the runtime to the proper subset of insns could be a major point for bugs. Signed-off-by: Richard Henderson Reviewed-by: Peter Maydell Message-id: 20220620175235.60881-18-richard.henderson@linaro.org Signed-off-by: Peter Maydell --- docs/system/arm/cpu-features.rst | 56 +++++++++++++++ target/arm/cpu.h | 2 + target/arm/internals.h | 1 + target/arm/cpu.c | 14 +++- target/arm/cpu64.c | 114 +++++++++++++++++++++++++++++-- 5 files changed, 180 insertions(+), 7 deletions(-) diff --git a/docs/system/arm/cpu-features.rst b/docs/system/arm/cpu-feature= s.rst index 3e626c4b68a..3fd76fa0b4f 100644 --- a/docs/system/arm/cpu-features.rst +++ b/docs/system/arm/cpu-features.rst @@ -372,6 +372,31 @@ verbose command lines. However, the recommended way t= o select vector lengths is to explicitly enable each desired length. Therefore only example's (1), (4), and (6) exhibit recommended uses of the properties. =20 +SME CPU Property Examples +------------------------- + + 1) Disable SME:: + + $ qemu-system-aarch64 -M virt -cpu max,sme=3Doff + + 2) Implicitly enable all vector lengths for the ``max`` CPU type:: + + $ qemu-system-aarch64 -M virt -cpu max + + 3) Only enable the 256-bit vector length:: + + $ qemu-system-aarch64 -M virt -cpu max,sme256=3Don + + 3) Enable the 256-bit and 1024-bit vector lengths:: + + $ qemu-system-aarch64 -M virt -cpu max,sme256=3Don,sme1024=3Don + + 4) Disable the 512-bit vector length. This results in all the other + lengths supported by ``max`` defaulting to enabled + (128, 256, 1024 and 2048):: + + $ qemu-system-aarch64 -M virt -cpu max,sve512=3Doff + SVE User-mode Default Vector Length Property -------------------------------------------- =20 @@ -387,3 +412,34 @@ length supported by QEMU is 256. =20 If this property is set to ``-1`` then the default vector length is set to the maximum possible length. + +SME CPU Properties +=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D + +The SME CPU properties are much like the SVE properties: ``sme`` is +used to enable or disable the entire SME feature, and ``sme`` is +used to enable or disable specific vector lengths. Finally, +``sme_fa64`` is used to enable or disable ``FEAT_SME_FA64``, which +allows execution of the "full a64" instruction set while Streaming +SVE mode is enabled. + +SME is not supported by KVM at this time. + +At least one vector length must be enabled when ``sme`` is enabled, +and all vector lengths must be powers of 2. The maximum vector +length supported by qemu is 2048 bits. Otherwise, there are no +additional constraints on the set of vector lengths supported by SME. + +SME User-mode Default Vector Length Property +-------------------------------------------- + +For qemu-aarch64, the cpu propery ``sme-default-vector-length=3DN`` is +defined to mirror the Linux kernel parameter file +``/proc/sys/abi/sme_default_vector_length``. The default length, ``N``, +is in units of bytes and must be between 16 and 8192. +If not specified, the default vector length is 32. + +As with ``sve-default-vector-length``, if the default length is larger +than the maximum vector length enabled, the actual vector length will +be reduced. If this property is set to ``-1`` then the default vector +length is set to the maximum possible length. diff --git a/target/arm/cpu.h b/target/arm/cpu.h index d2b005f76c8..c018f97b77b 100644 --- a/target/arm/cpu.h +++ b/target/arm/cpu.h @@ -1060,9 +1060,11 @@ struct ArchCPU { #ifdef CONFIG_USER_ONLY /* Used to set the default vector length at process start. */ uint32_t sve_default_vq; + uint32_t sme_default_vq; #endif =20 ARMVQMap sve_vq; + ARMVQMap sme_vq; =20 /* Generic timer counter frequency, in Hz */ uint64_t gt_cntfrq_hz; diff --git a/target/arm/internals.h b/target/arm/internals.h index aef568adf75..c66f74a0db1 100644 --- a/target/arm/internals.h +++ b/target/arm/internals.h @@ -1289,6 +1289,7 @@ int arm_gdb_set_svereg(CPUARMState *env, uint8_t *buf= , int reg); int aarch64_fpu_gdb_get_reg(CPUARMState *env, GByteArray *buf, int reg); int aarch64_fpu_gdb_set_reg(CPUARMState *env, uint8_t *buf, int reg); void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp); +void arm_cpu_sme_finalize(ARMCPU *cpu, Error **errp); void arm_cpu_pauth_finalize(ARMCPU *cpu, Error **errp); void arm_cpu_lpa2_finalize(ARMCPU *cpu, Error **errp); #endif diff --git a/target/arm/cpu.c b/target/arm/cpu.c index 660fd8b8b90..bb44ad45aa1 100644 --- a/target/arm/cpu.c +++ b/target/arm/cpu.c @@ -1123,11 +1123,13 @@ static void arm_cpu_initfn(Object *obj) #ifdef CONFIG_USER_ONLY # ifdef TARGET_AARCH64 /* - * The linux kernel defaults to 512-bit vectors, when sve is supported. - * See documentation for /proc/sys/abi/sve_default_vector_length, and - * our corresponding sve-default-vector-length cpu property. + * The linux kernel defaults to 512-bit for SVE, and 256-bit for SME. + * These values were chosen to fit within the default signal frame. + * See documentation for /proc/sys/abi/{sve,sme}_default_vector_length, + * and our corresponding cpu property. */ cpu->sve_default_vq =3D 4; + cpu->sme_default_vq =3D 2; # endif #else /* Our inbound IRQ and FIQ lines */ @@ -1430,6 +1432,12 @@ void arm_cpu_finalize_features(ARMCPU *cpu, Error **= errp) return; } =20 + arm_cpu_sme_finalize(cpu, &local_err); + if (local_err !=3D NULL) { + error_propagate(errp, local_err); + return; + } + arm_cpu_pauth_finalize(cpu, &local_err); if (local_err !=3D NULL) { error_propagate(errp, local_err); diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c index 6f6ee57a914..19188d6cc2a 100644 --- a/target/arm/cpu64.c +++ b/target/arm/cpu64.c @@ -589,10 +589,13 @@ static void cpu_arm_get_vq(Object *obj, Visitor *v, c= onst char *name, ARMCPU *cpu =3D ARM_CPU(obj); ARMVQMap *vq_map =3D opaque; uint32_t vq =3D atoi(&name[3]) / 128; + bool sve =3D vq_map =3D=3D &cpu->sve_vq; bool value; =20 - /* All vector lengths are disabled when SVE is off. */ - if (!cpu_isar_feature(aa64_sve, cpu)) { + /* All vector lengths are disabled when feature is off. */ + if (sve + ? !cpu_isar_feature(aa64_sve, cpu) + : !cpu_isar_feature(aa64_sme, cpu)) { value =3D false; } else { value =3D extract32(vq_map->map, vq - 1, 1); @@ -636,8 +639,80 @@ static void cpu_arm_set_sve(Object *obj, bool value, E= rror **errp) cpu->isar.id_aa64pfr0 =3D t; } =20 +void arm_cpu_sme_finalize(ARMCPU *cpu, Error **errp) +{ + uint32_t vq_map =3D cpu->sme_vq.map; + uint32_t vq_init =3D cpu->sme_vq.init; + uint32_t vq_supported =3D cpu->sme_vq.supported; + uint32_t vq; + + if (vq_map =3D=3D 0) { + if (!cpu_isar_feature(aa64_sme, cpu)) { + cpu->isar.id_aa64smfr0 =3D 0; + return; + } + + /* TODO: KVM will require limitations via SMCR_EL2. */ + vq_map =3D vq_supported & ~vq_init; + + if (vq_map =3D=3D 0) { + vq =3D ctz32(vq_supported) + 1; + error_setg(errp, "cannot disable sme%d", vq * 128); + error_append_hint(errp, "All SME vector lengths are disabled.\= n"); + error_append_hint(errp, "With SME enabled, at least one " + "vector length must be enabled.\n"); + return; + } + } else { + if (!cpu_isar_feature(aa64_sme, cpu)) { + vq =3D 32 - clz32(vq_map); + error_setg(errp, "cannot enable sme%d", vq * 128); + error_append_hint(errp, "SME must be enabled to enable " + "vector lengths.\n"); + error_append_hint(errp, "Add sme=3Don to the CPU property list= .\n"); + return; + } + /* TODO: KVM will require limitations via SMCR_EL2. */ + } + + cpu->sme_vq.map =3D vq_map; +} + +static bool cpu_arm_get_sme(Object *obj, Error **errp) +{ + ARMCPU *cpu =3D ARM_CPU(obj); + return cpu_isar_feature(aa64_sme, cpu); +} + +static void cpu_arm_set_sme(Object *obj, bool value, Error **errp) +{ + ARMCPU *cpu =3D ARM_CPU(obj); + uint64_t t; + + t =3D cpu->isar.id_aa64pfr1; + t =3D FIELD_DP64(t, ID_AA64PFR1, SME, value); + cpu->isar.id_aa64pfr1 =3D t; +} + +static bool cpu_arm_get_sme_fa64(Object *obj, Error **errp) +{ + ARMCPU *cpu =3D ARM_CPU(obj); + return cpu_isar_feature(aa64_sme, cpu) && + cpu_isar_feature(aa64_sme_fa64, cpu); +} + +static void cpu_arm_set_sme_fa64(Object *obj, bool value, Error **errp) +{ + ARMCPU *cpu =3D ARM_CPU(obj); + uint64_t t; + + t =3D cpu->isar.id_aa64smfr0; + t =3D FIELD_DP64(t, ID_AA64SMFR0, FA64, value); + cpu->isar.id_aa64smfr0 =3D t; +} + #ifdef CONFIG_USER_ONLY -/* Mirror linux /proc/sys/abi/sve_default_vector_length. */ +/* Mirror linux /proc/sys/abi/{sve,sme}_default_vector_length. */ static void cpu_arm_set_default_vec_len(Object *obj, Visitor *v, const char *name, void *opaque, Error **errp) @@ -663,7 +738,11 @@ static void cpu_arm_set_default_vec_len(Object *obj, V= isitor *v, * and is the maximum architectural width of ZCR_ELx.LEN. */ if (remainder || default_vq < 1 || default_vq > 512) { - error_setg(errp, "cannot set sve-default-vector-length"); + ARMCPU *cpu =3D ARM_CPU(obj); + const char *which =3D + (ptr_default_vq =3D=3D &cpu->sve_default_vq ? "sve" : "sme"); + + error_setg(errp, "cannot set %s-default-vector-length", which); if (remainder) { error_append_hint(errp, "Vector length not a multiple of 16\n"= ); } else if (default_vq < 1) { @@ -712,6 +791,31 @@ static void aarch64_add_sve_properties(Object *obj) #endif } =20 +static void aarch64_add_sme_properties(Object *obj) +{ + ARMCPU *cpu =3D ARM_CPU(obj); + uint32_t vq; + + object_property_add_bool(obj, "sme", cpu_arm_get_sme, cpu_arm_set_sme); + object_property_add_bool(obj, "sme_fa64", cpu_arm_get_sme_fa64, + cpu_arm_set_sme_fa64); + + for (vq =3D 1; vq <=3D ARM_MAX_VQ; vq <<=3D 1) { + char name[8]; + sprintf(name, "sme%d", vq * 128); + object_property_add(obj, name, "bool", cpu_arm_get_vq, + cpu_arm_set_vq, NULL, &cpu->sme_vq); + } + +#ifdef CONFIG_USER_ONLY + /* Mirror linux /proc/sys/abi/sme_default_vector_length. */ + object_property_add(obj, "sme-default-vector-length", "int32", + cpu_arm_get_default_vec_len, + cpu_arm_set_default_vec_len, NULL, + &cpu->sme_default_vq); +#endif +} + void arm_cpu_pauth_finalize(ARMCPU *cpu, Error **errp) { int arch_val =3D 0, impdef_val =3D 0; @@ -977,9 +1081,11 @@ static void aarch64_max_initfn(Object *obj) #endif =20 cpu->sve_vq.supported =3D MAKE_64BIT_MASK(0, ARM_MAX_VQ); + cpu->sme_vq.supported =3D SVE_VQ_POW2_MAP; =20 aarch64_add_pauth_properties(obj); aarch64_add_sve_properties(obj); + aarch64_add_sme_properties(obj); object_property_add(obj, "sve-max-vq", "uint32", cpu_max_get_sve_max_v= q, cpu_max_set_sve_max_vq, NULL, NULL); qdev_property_add_static(DEVICE(obj), &arm_cpu_lpa2_property); --=20 2.25.1