diff options
| -rw-r--r-- | docs/arm-cpu-features.rst | 168 | ||||
| -rw-r--r-- | include/qemu/bitops.h | 1 | ||||
| -rw-r--r-- | target/arm/cpu.c | 19 | ||||
| -rw-r--r-- | target/arm/cpu.h | 19 | ||||
| -rw-r--r-- | target/arm/cpu64.c | 192 | ||||
| -rw-r--r-- | target/arm/helper.c | 10 | ||||
| -rw-r--r-- | target/arm/monitor.c | 12 | ||||
| -rw-r--r-- | tests/arm-cpu-features.c | 194 |
8 files changed, 606 insertions, 9 deletions
diff --git a/docs/arm-cpu-features.rst b/docs/arm-cpu-features.rst index c79dcff..2ea4d6e 100644 --- a/docs/arm-cpu-features.rst +++ b/docs/arm-cpu-features.rst @@ -48,18 +48,31 @@ block in the script for usage) is used to issue the QMP commands. (QEMU) query-cpu-model-expansion type=full model={"name":"max"} { "return": { "model": { "name": "max", "props": { - "pmu": true, "aarch64": true + "sve1664": true, "pmu": true, "sve1792": true, "sve1920": true, + "sve128": true, "aarch64": true, "sve1024": true, "sve": true, + "sve640": true, "sve768": true, "sve1408": true, "sve256": true, + "sve1152": true, "sve512": true, "sve384": true, "sve1536": true, + "sve896": true, "sve1280": true, "sve2048": true }}}} -We see that the `max` CPU type has the `pmu` and `aarch64` CPU features. -We also see that the CPU features are enabled, as they are all `true`. +We see that the `max` CPU type has the `pmu`, `aarch64`, `sve`, and many +`sve<N>` CPU features. We also see that all the CPU features are +enabled, as they are all `true`. (The `sve<N>` CPU features are all +optional SVE vector lengths (see "SVE CPU Properties"). While with TCG +all SVE vector lengths can be supported, when KVM is in use it's more +likely that only a few lengths will be supported, if SVE is supported at +all.) (2) Let's try to disable the PMU:: (QEMU) query-cpu-model-expansion type=full model={"name":"max","props":{"pmu":false}} { "return": { "model": { "name": "max", "props": { - "pmu": false, "aarch64": true + "sve1664": true, "pmu": false, "sve1792": true, "sve1920": true, + "sve128": true, "aarch64": true, "sve1024": true, "sve": true, + "sve640": true, "sve768": true, "sve1408": true, "sve256": true, + "sve1152": true, "sve512": true, "sve384": true, "sve1536": true, + "sve896": true, "sve1280": true, "sve2048": true }}}} We see it worked, as `pmu` is now `false`. @@ -75,7 +88,22 @@ We see it worked, as `pmu` is now `false`. It looks like this feature is limited to a configuration we do not currently have. -(4) Let's try probing CPU features for the Cortex-A15 CPU type:: +(4) Let's disable `sve` and see what happens to all the optional SVE + vector lengths:: + + (QEMU) query-cpu-model-expansion type=full model={"name":"max","props":{"sve":false}} + { "return": { + "model": { "name": "max", "props": { + "sve1664": false, "pmu": true, "sve1792": false, "sve1920": false, + "sve128": false, "aarch64": true, "sve1024": false, "sve": false, + "sve640": false, "sve768": false, "sve1408": false, "sve256": false, + "sve1152": false, "sve512": false, "sve384": false, "sve1536": false, + "sve896": false, "sve1280": false, "sve2048": false + }}}} + +As expected they are now all `false`. + +(5) Let's try probing CPU features for the Cortex-A15 CPU type:: (QEMU) query-cpu-model-expansion type=full model={"name":"cortex-a15"} {"return": {"model": {"name": "cortex-a15", "props": {"pmu": true}}}} @@ -131,7 +159,133 @@ After determining which CPU features are available and supported for a given CPU type, then they may be selectively enabled or disabled on the QEMU command line with that CPU type:: - $ qemu-system-aarch64 -M virt -cpu max,pmu=off + $ qemu-system-aarch64 -M virt -cpu max,pmu=off,sve=on,sve128=on,sve256=on + +The example above disables the PMU and enables the first two SVE vector +lengths for the `max` CPU type. Note, the `sve=on` isn't actually +necessary, because, as we observed above with our probe of the `max` CPU +type, `sve` is already on by default. Also, based on our probe of +defaults, it would seem we need to disable many SVE vector lengths, rather +than only enabling the two we want. This isn't the case, because, as +disabling many SVE vector lengths would be quite verbose, the `sve<N>` CPU +properties have special semantics (see "SVE CPU Property Parsing +Semantics"). + +SVE CPU Properties +================== + +There are two types of SVE CPU properties: `sve` and `sve<N>`. The first +is used to enable or disable the entire SVE feature, just as the `pmu` +CPU property completely enables or disables the PMU. The second type +is used to enable or disable specific vector lengths, where `N` is the +number of bits of the length. The `sve<N>` CPU properties have special +dependencies and constraints, see "SVE CPU Property Dependencies and +Constraints" below. Additionally, as we want all supported vector lengths +to be enabled by default, then, in order to avoid overly verbose command +lines (command lines full of `sve<N>=off`, for all `N` not wanted), we +provide the parsing semantics listed in "SVE CPU Property Parsing +Semantics". + +SVE CPU Property Dependencies and Constraints +--------------------------------------------- + + 1) At least one vector length must be enabled when `sve` is enabled. + + 2) If a vector length `N` is enabled, then all power-of-two vector + lengths smaller than `N` must also be enabled. E.g. if `sve512` + is enabled, then the 128-bit and 256-bit vector lengths must also + be enabled. + +SVE CPU Property Parsing Semantics +---------------------------------- + + 1) If SVE is disabled (`sve=off`), then which SVE vector lengths + are enabled or disabled is irrelevant to the guest, as the entire + SVE feature is disabled and that disables all vector lengths for + the guest. However QEMU will still track any `sve<N>` CPU + properties provided by the user. If later an `sve=on` is provided, + then the guest will get only the enabled lengths. If no `sve=on` + is provided and there are explicitly enabled vector lengths, then + an error is generated. + + 2) If SVE is enabled (`sve=on`), but no `sve<N>` CPU properties are + provided, then all supported vector lengths are enabled, including + the non-power-of-two lengths. + + 3) If SVE is enabled, then an error is generated when attempting to + disable the last enabled vector length (see constraint (1) of "SVE + CPU Property Dependencies and Constraints"). + + 4) If one or more vector lengths have been explicitly enabled and at + at least one of the dependency lengths of the maximum enabled length + has been explicitly disabled, then an error is generated (see + constraint (2) of "SVE CPU Property Dependencies and Constraints"). + + 5) If one or more `sve<N>` CPU properties are set `off`, but no `sve<N>`, + CPU properties are set `on`, then the specified vector lengths are + disabled but the default for any unspecified lengths remains enabled. + Disabling a power-of-two vector length also disables all vector + lengths larger than the power-of-two length (see constraint (2) of + "SVE CPU Property Dependencies and Constraints"). + + 6) If one or more `sve<N>` CPU properties are set to `on`, then they + are enabled and all unspecified lengths default to disabled, except + for the required lengths per constraint (2) of "SVE CPU Property + Dependencies and Constraints", which will even be auto-enabled if + they were not explicitly enabled. + + 7) If SVE was disabled (`sve=off`), allowing all vector lengths to be + explicitly disabled (i.e. avoiding the error specified in (3) of + "SVE CPU Property Parsing Semantics"), then if later an `sve=on` is + provided an error will be generated. To avoid this error, one must + enable at least one vector length prior to enabling SVE. + +SVE CPU Property Examples +------------------------- + + 1) Disable SVE:: + + $ qemu-system-aarch64 -M virt -cpu max,sve=off + + 2) Implicitly enable all vector lengths for the `max` CPU type:: + + $ qemu-system-aarch64 -M virt -cpu max + + 3) Only enable the 128-bit vector length:: + + $ qemu-system-aarch64 -M virt -cpu max,sve128=on + + 4) Disable the 512-bit vector length and all larger vector lengths, + since 512 is a power-of-two. This results in all the smaller, + uninitialized lengths (128, 256, and 384) defaulting to enabled:: + + $ qemu-system-aarch64 -M virt -cpu max,sve512=off + + 5) Enable the 128-bit, 256-bit, and 512-bit vector lengths:: + + $ qemu-system-aarch64 -M virt -cpu max,sve128=on,sve256=on,sve512=on + + 6) The same as (5), but since the 128-bit and 256-bit vector + lengths are required for the 512-bit vector length to be enabled, + then allow them to be auto-enabled:: + + $ qemu-system-aarch64 -M virt -cpu max,sve512=on + + 7) Do the same as (6), but by first disabling SVE and then re-enabling it:: + + $ qemu-system-aarch64 -M virt -cpu max,sve=off,sve512=on,sve=on + + 8) Force errors regarding the last vector length:: + + $ qemu-system-aarch64 -M virt -cpu max,sve128=off + $ qemu-system-aarch64 -M virt -cpu max,sve=off,sve128=off,sve=on + +SVE CPU Property Recommendations +-------------------------------- -The example above disables the PMU for the `max` CPU type. +The examples in "SVE CPU Property Examples" exhibit many ways to select +vector lengths which developers may find useful in order to avoid overly +verbose command lines. However, the recommended way to select vector +lengths is to explicitly enable each desired length. Therefore only +example's (1), (3), and (5) exhibit recommended uses of the properties. diff --git a/include/qemu/bitops.h b/include/qemu/bitops.h index 3f0926c..ee76552 100644 --- a/include/qemu/bitops.h +++ b/include/qemu/bitops.h @@ -20,6 +20,7 @@ #define BITS_PER_LONG (sizeof (unsigned long) * BITS_PER_BYTE) #define BIT(nr) (1UL << (nr)) +#define BIT_ULL(nr) (1ULL << (nr)) #define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG)) #define BIT_WORD(nr) ((nr) / BITS_PER_LONG) #define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long)) diff --git a/target/arm/cpu.c b/target/arm/cpu.c index 72a27ec..17d1f2b 100644 --- a/target/arm/cpu.c +++ b/target/arm/cpu.c @@ -1198,6 +1198,19 @@ static void arm_cpu_finalizefn(Object *obj) #endif } +void arm_cpu_finalize_features(ARMCPU *cpu, Error **errp) +{ + Error *local_err = NULL; + + if (arm_feature(&cpu->env, ARM_FEATURE_AARCH64)) { + arm_cpu_sve_finalize(cpu, &local_err); + if (local_err != NULL) { + error_propagate(errp, local_err); + return; + } + } +} + static void arm_cpu_realizefn(DeviceState *dev, Error **errp) { CPUState *cs = CPU(dev); @@ -1254,6 +1267,12 @@ static void arm_cpu_realizefn(DeviceState *dev, Error **errp) return; } + arm_cpu_finalize_features(cpu, &local_err); + if (local_err != NULL) { + error_propagate(errp, local_err); + return; + } + if (arm_feature(env, ARM_FEATURE_AARCH64) && cpu->has_vfp != cpu->has_neon) { /* diff --git a/target/arm/cpu.h b/target/arm/cpu.h index d844ea2..a044d60 100644 --- a/target/arm/cpu.h +++ b/target/arm/cpu.h @@ -184,8 +184,13 @@ typedef struct { #ifdef TARGET_AARCH64 # define ARM_MAX_VQ 16 +void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp); +uint32_t arm_cpu_vq_map_next_smaller(ARMCPU *cpu, uint32_t vq); #else # define ARM_MAX_VQ 1 +static inline void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp) { } +static inline uint32_t arm_cpu_vq_map_next_smaller(ARMCPU *cpu, uint32_t vq) +{ return 0; } #endif typedef struct ARMVectorReg { @@ -918,6 +923,18 @@ struct ARMCPU { /* Used to set the maximum vector length the cpu will support. */ uint32_t sve_max_vq; + + /* + * In sve_vq_map each set bit is a supported vector length of + * (bit-number + 1) * 16 bytes, i.e. each bit number + 1 is the vector + * length in quadwords. + * + * While processing properties during initialization, corresponding + * sve_vq_init bits are set for bits in sve_vq_map that have been + * set by properties. + */ + DECLARE_BITMAP(sve_vq_map, ARM_MAX_VQ); + DECLARE_BITMAP(sve_vq_init, ARM_MAX_VQ); }; void arm_cpu_post_init(Object *obj); @@ -1837,6 +1854,8 @@ static inline int arm_feature(CPUARMState *env, int feature) return (env->features & (1ULL << feature)) != 0; } +void arm_cpu_finalize_features(ARMCPU *cpu, Error **errp); + #if !defined(CONFIG_USER_ONLY) /* Return true if exception levels below EL3 are in secure state, * or would be following an exception return to that level. diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c index 89a8ae7..34b0ba2 100644 --- a/target/arm/cpu64.c +++ b/target/arm/cpu64.c @@ -256,6 +256,151 @@ static void aarch64_a72_initfn(Object *obj) define_arm_cp_regs(cpu, cortex_a72_a57_a53_cp_reginfo); } +void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp) +{ + /* + * If any vector lengths are explicitly enabled with sve<N> properties, + * then all other lengths are implicitly disabled. If sve-max-vq is + * specified then it is the same as explicitly enabling all lengths + * up to and including the specified maximum, which means all larger + * lengths will be implicitly disabled. If no sve<N> properties + * are enabled and sve-max-vq is not specified, then all lengths not + * explicitly disabled will be enabled. Additionally, all power-of-two + * vector lengths less than the maximum enabled length will be + * automatically enabled and all vector lengths larger than the largest + * disabled power-of-two vector length will be automatically disabled. + * Errors are generated if the user provided input that interferes with + * any of the above. Finally, if SVE is not disabled, then at least one + * vector length must be enabled. + */ + DECLARE_BITMAP(tmp, ARM_MAX_VQ); + uint32_t vq, max_vq = 0; + + /* + * Process explicit sve<N> properties. + * From the properties, sve_vq_map<N> implies sve_vq_init<N>. + * Check first for any sve<N> enabled. + */ + if (!bitmap_empty(cpu->sve_vq_map, ARM_MAX_VQ)) { + max_vq = find_last_bit(cpu->sve_vq_map, ARM_MAX_VQ) + 1; + + if (cpu->sve_max_vq && max_vq > cpu->sve_max_vq) { + error_setg(errp, "cannot enable sve%d", max_vq * 128); + error_append_hint(errp, "sve%d is larger than the maximum vector " + "length, sve-max-vq=%d (%d bits)\n", + max_vq * 128, cpu->sve_max_vq, + cpu->sve_max_vq * 128); + return; + } + + /* Propagate enabled bits down through required powers-of-two. */ + for (vq = pow2floor(max_vq); vq >= 1; vq >>= 1) { + if (!test_bit(vq - 1, cpu->sve_vq_init)) { + set_bit(vq - 1, cpu->sve_vq_map); + } + } + } else if (cpu->sve_max_vq == 0) { + /* + * No explicit bits enabled, and no implicit bits from sve-max-vq. + */ + if (!cpu_isar_feature(aa64_sve, cpu)) { + /* SVE is disabled and so are all vector lengths. Good. */ + return; + } + + /* Disabling a power-of-two disables all larger lengths. */ + if (test_bit(0, cpu->sve_vq_init)) { + error_setg(errp, "cannot disable sve128"); + error_append_hint(errp, "Disabling sve128 results in all vector " + "lengths being disabled.\n"); + error_append_hint(errp, "With SVE enabled, at least one vector " + "length must be enabled.\n"); + return; + } + for (vq = 2; vq <= ARM_MAX_VQ; vq <<= 1) { + if (test_bit(vq - 1, cpu->sve_vq_init)) { + break; + } + } + max_vq = vq <= ARM_MAX_VQ ? vq - 1 : ARM_MAX_VQ; + + bitmap_complement(cpu->sve_vq_map, cpu->sve_vq_init, max_vq); + max_vq = find_last_bit(cpu->sve_vq_map, max_vq) + 1; + } + + /* + * Process the sve-max-vq property. + * Note that we know from the above that no bit above + * sve-max-vq is currently set. + */ + if (cpu->sve_max_vq != 0) { + max_vq = cpu->sve_max_vq; + + if (!test_bit(max_vq - 1, cpu->sve_vq_map) && + test_bit(max_vq - 1, cpu->sve_vq_init)) { + error_setg(errp, "cannot disable sve%d", max_vq * 128); + error_append_hint(errp, "The maximum vector length must be " + "enabled, sve-max-vq=%d (%d bits)\n", + max_vq, max_vq * 128); + return; + } + + /* Set all bits not explicitly set within sve-max-vq. */ + bitmap_complement(tmp, cpu->sve_vq_init, max_vq); + bitmap_or(cpu->sve_vq_map, cpu->sve_vq_map, tmp, max_vq); + } + + /* + * We should know what max-vq is now. Also, as we're done + * manipulating sve-vq-map, we ensure any bits above max-vq + * are clear, just in case anybody looks. + */ + assert(max_vq != 0); + bitmap_clear(cpu->sve_vq_map, max_vq, ARM_MAX_VQ - max_vq); + + /* Ensure all required powers-of-two are enabled. */ + for (vq = pow2floor(max_vq); vq >= 1; vq >>= 1) { + if (!test_bit(vq - 1, cpu->sve_vq_map)) { + error_setg(errp, "cannot disable sve%d", vq * 128); + error_append_hint(errp, "sve%d is required as it " + "is a power-of-two length smaller than " + "the maximum, sve%d\n", + vq * 128, max_vq * 128); + return; + } + } + + /* + * Now that we validated all our vector lengths, the only question + * left to answer is if we even want SVE at all. + */ + if (!cpu_isar_feature(aa64_sve, cpu)) { + error_setg(errp, "cannot enable sve%d", max_vq * 128); + error_append_hint(errp, "SVE must be enabled to enable vector " + "lengths.\n"); + error_append_hint(errp, "Add sve=on to the CPU property list.\n"); + return; + } + + /* From now on sve_max_vq is the actual maximum supported length. */ + cpu->sve_max_vq = max_vq; +} + +uint32_t arm_cpu_vq_map_next_smaller(ARMCPU *cpu, uint32_t vq) +{ + uint32_t bitnum; + + /* + * We allow vq == ARM_MAX_VQ + 1 to be input because the caller may want + * to find the maximum vq enabled, which may be ARM_MAX_VQ, but this + * function always returns the next smaller than the input. + */ + assert(vq && vq <= ARM_MAX_VQ + 1); + + bitnum = find_last_bit(cpu->sve_vq_map, vq - 1); + return bitnum == vq - 1 ? 0 : bitnum + 1; +} + static void cpu_max_get_sve_max_vq(Object *obj, Visitor *v, const char *name, void *opaque, Error **errp) { @@ -287,6 +432,44 @@ static void cpu_max_set_sve_max_vq(Object *obj, Visitor *v, const char *name, error_propagate(errp, err); } +static void cpu_arm_get_sve_vq(Object *obj, Visitor *v, const char *name, + void *opaque, Error **errp) +{ + ARMCPU *cpu = ARM_CPU(obj); + uint32_t vq = atoi(&name[3]) / 128; + bool value; + + /* All vector lengths are disabled when SVE is off. */ + if (!cpu_isar_feature(aa64_sve, cpu)) { + value = false; + } else { + value = test_bit(vq - 1, cpu->sve_vq_map); + } + visit_type_bool(v, name, &value, errp); +} + +static void cpu_arm_set_sve_vq(Object *obj, Visitor *v, const char *name, + void *opaque, Error **errp) +{ + ARMCPU *cpu = ARM_CPU(obj); + uint32_t vq = atoi(&name[3]) / 128; + Error *err = NULL; + bool value; + + visit_type_bool(v, name, &value, &err); + if (err) { + error_propagate(errp, err); + return; + } + + if (value) { + set_bit(vq - 1, cpu->sve_vq_map); + } else { + clear_bit(vq - 1, cpu->sve_vq_map); + } + set_bit(vq - 1, cpu->sve_vq_init); +} + static void cpu_arm_get_sve(Object *obj, Visitor *v, const char *name, void *opaque, Error **errp) { @@ -323,6 +506,7 @@ static void cpu_arm_set_sve(Object *obj, Visitor *v, const char *name, static void aarch64_max_initfn(Object *obj) { ARMCPU *cpu = ARM_CPU(obj); + uint32_t vq; if (kvm_enabled()) { kvm_arm_set_cpu_features_from_host(cpu); @@ -426,11 +610,17 @@ static void aarch64_max_initfn(Object *obj) cpu->dcz_blocksize = 7; /* 512 bytes */ #endif - cpu->sve_max_vq = ARM_MAX_VQ; object_property_add(obj, "sve-max-vq", "uint32", cpu_max_get_sve_max_vq, cpu_max_set_sve_max_vq, NULL, NULL, &error_fatal); object_property_add(obj, "sve", "bool", cpu_arm_get_sve, cpu_arm_set_sve, NULL, NULL, &error_fatal); + + for (vq = 1; vq <= ARM_MAX_VQ; ++vq) { + char name[8]; + sprintf(name, "sve%d", vq * 128); + object_property_add(obj, name, "bool", cpu_arm_get_sve_vq, + cpu_arm_set_sve_vq, NULL, NULL, &error_fatal); + } } } diff --git a/target/arm/helper.c b/target/arm/helper.c index 63815fc..be67e2c 100644 --- a/target/arm/helper.c +++ b/target/arm/helper.c @@ -5361,6 +5361,13 @@ int sve_exception_el(CPUARMState *env, int el) return 0; } +static uint32_t sve_zcr_get_valid_len(ARMCPU *cpu, uint32_t start_len) +{ + uint32_t start_vq = (start_len & 0xf) + 1; + + return arm_cpu_vq_map_next_smaller(cpu, start_vq + 1) - 1; +} + /* * Given that SVE is enabled, return the vector length for EL. */ @@ -5378,7 +5385,8 @@ uint32_t sve_zcr_len_for_el(CPUARMState *env, int el) if (arm_feature(env, ARM_FEATURE_EL3)) { zcr_len = MIN(zcr_len, 0xf & (uint32_t)env->vfp.zcr_el[3]); } - return zcr_len; + + return sve_zcr_get_valid_len(cpu, zcr_len); } static void zcr_write(CPUARMState *env, const ARMCPRegInfo *ri, diff --git a/target/arm/monitor.c b/target/arm/monitor.c index 2209b27..fa054f8 100644 --- a/target/arm/monitor.c +++ b/target/arm/monitor.c @@ -90,6 +90,8 @@ GICCapabilityList *qmp_query_gic_capabilities(Error **errp) return head; } +QEMU_BUILD_BUG_ON(ARM_MAX_VQ > 16); + /* * These are cpu model features we want to advertise. The order here * matters as this is the order in which qmp_query_cpu_model_expansion @@ -98,6 +100,9 @@ GICCapabilityList *qmp_query_gic_capabilities(Error **errp) */ static const char *cpu_model_advertised_features[] = { "aarch64", "pmu", "sve", + "sve128", "sve256", "sve384", "sve512", + "sve640", "sve768", "sve896", "sve1024", "sve1152", "sve1280", + "sve1408", "sve1536", "sve1664", "sve1792", "sve1920", "sve2048", NULL }; @@ -186,6 +191,9 @@ CpuModelExpansionInfo *qmp_query_cpu_model_expansion(CpuModelExpansionType type, if (!err) { visit_check_struct(visitor, &err); } + if (!err) { + arm_cpu_finalize_features(ARM_CPU(obj), &err); + } visit_end_struct(visitor, NULL); visit_free(visitor); if (err) { @@ -193,6 +201,10 @@ CpuModelExpansionInfo *qmp_query_cpu_model_expansion(CpuModelExpansionType type, error_propagate(errp, err); return NULL; } + } else { + Error *err = NULL; + arm_cpu_finalize_features(ARM_CPU(obj), &err); + assert(err == NULL); } expansion_info = g_new0(CpuModelExpansionInfo, 1); diff --git a/tests/arm-cpu-features.c b/tests/arm-cpu-features.c index 2ad9c2c..45fa3cb 100644 --- a/tests/arm-cpu-features.c +++ b/tests/arm-cpu-features.c @@ -9,10 +9,17 @@ * See the COPYING file in the top-level directory. */ #include "qemu/osdep.h" +#include "qemu/bitops.h" #include "libqtest.h" #include "qapi/qmp/qdict.h" #include "qapi/qmp/qjson.h" +/* + * We expect the SVE max-vq to be 16. Also it must be <= 64 + * for our test code, otherwise 'vls' can't just be a uint64_t. + */ +#define SVE_MAX_VQ 16 + #define MACHINE "-machine virt,gic-version=max,accel=tcg " #define MACHINE_KVM "-machine virt,gic-version=max,accel=kvm:tcg " #define QUERY_HEAD "{ 'execute': 'query-cpu-model-expansion', " \ @@ -175,6 +182,183 @@ static void assert_bad_props(QTestState *qts, const char *cpu_type) qobject_unref(resp); } +static uint64_t resp_get_sve_vls(QDict *resp) +{ + QDict *props; + const QDictEntry *e; + uint64_t vls = 0; + int n = 0; + + g_assert(resp); + g_assert(resp_has_props(resp)); + + props = resp_get_props(resp); + + for (e = qdict_first(props); e; e = qdict_next(props, e)) { + if (strlen(e->key) > 3 && !strncmp(e->key, "sve", 3) && + g_ascii_isdigit(e->key[3])) { + char *endptr; + int bits; + + bits = g_ascii_strtoll(&e->key[3], &endptr, 10); + if (!bits || *endptr != '\0') { + continue; + } + + if (qdict_get_bool(props, e->key)) { + vls |= BIT_ULL((bits / 128) - 1); + } + ++n; + } + } + + g_assert(n == SVE_MAX_VQ); + + return vls; +} + +#define assert_sve_vls(qts, cpu_type, expected_vls, fmt, ...) \ +({ \ + QDict *_resp = do_query(qts, cpu_type, fmt, ##__VA_ARGS__); \ + g_assert(_resp); \ + g_assert(resp_has_props(_resp)); \ + g_assert(resp_get_sve_vls(_resp) == expected_vls); \ + qobject_unref(_resp); \ +}) + +static void sve_tests_default(QTestState *qts, const char *cpu_type) +{ + /* + * With no sve-max-vq or sve<N> properties on the command line + * the default is to have all vector lengths enabled. This also + * tests that 'sve' is 'on' by default. + */ + assert_sve_vls(qts, cpu_type, BIT_ULL(SVE_MAX_VQ) - 1, NULL); + + /* With SVE off, all vector lengths should also be off. */ + assert_sve_vls(qts, cpu_type, 0, "{ 'sve': false }"); + + /* With SVE on, we must have at least one vector length enabled. */ + assert_error(qts, cpu_type, "cannot disable sve128", "{ 'sve128': false }"); + + /* Basic enable/disable tests. */ + assert_sve_vls(qts, cpu_type, 0x7, "{ 'sve384': true }"); + assert_sve_vls(qts, cpu_type, ((BIT_ULL(SVE_MAX_VQ) - 1) & ~BIT_ULL(2)), + "{ 'sve384': false }"); + + /* + * --------------------------------------------------------------------- + * power-of-two(vq) all-power- can can + * of-two(< vq) enable disable + * --------------------------------------------------------------------- + * vq < max_vq no MUST* yes yes + * vq < max_vq yes MUST* yes no + * --------------------------------------------------------------------- + * vq == max_vq n/a MUST* yes** yes** + * --------------------------------------------------------------------- + * vq > max_vq n/a no no yes + * vq > max_vq n/a yes yes yes + * --------------------------------------------------------------------- + * + * [*] "MUST" means this requirement must already be satisfied, + * otherwise 'max_vq' couldn't itself be enabled. + * + * [**] Not testable with the QMP interface, only with the command line. + */ + + /* max_vq := 8 */ + assert_sve_vls(qts, cpu_type, 0x8b, "{ 'sve1024': true }"); + + /* max_vq := 8, vq < max_vq, !power-of-two(vq) */ + assert_sve_vls(qts, cpu_type, 0x8f, + "{ 'sve1024': true, 'sve384': true }"); + assert_sve_vls(qts, cpu_type, 0x8b, + "{ 'sve1024': true, 'sve384': false }"); + + /* max_vq := 8, vq < max_vq, power-of-two(vq) */ + assert_sve_vls(qts, cpu_type, 0x8b, + "{ 'sve1024': true, 'sve256': true }"); + assert_error(qts, cpu_type, "cannot disable sve256", + "{ 'sve1024': true, 'sve256': false }"); + + /* max_vq := 3, vq > max_vq, !all-power-of-two(< vq) */ + assert_error(qts, cpu_type, "cannot disable sve512", + "{ 'sve384': true, 'sve512': false, 'sve640': true }"); + + /* + * We can disable power-of-two vector lengths when all larger lengths + * are also disabled. We only need to disable the power-of-two length, + * as all non-enabled larger lengths will then be auto-disabled. + */ + assert_sve_vls(qts, cpu_type, 0x7, "{ 'sve512': false }"); + + /* max_vq := 3, vq > max_vq, all-power-of-two(< vq) */ + assert_sve_vls(qts, cpu_type, 0x1f, + "{ 'sve384': true, 'sve512': true, 'sve640': true }"); + assert_sve_vls(qts, cpu_type, 0xf, + "{ 'sve384': true, 'sve512': true, 'sve640': false }"); +} + +static void sve_tests_sve_max_vq_8(const void *data) +{ + QTestState *qts; + + qts = qtest_init(MACHINE "-cpu max,sve-max-vq=8"); + + assert_sve_vls(qts, "max", BIT_ULL(8) - 1, NULL); + + /* + * Disabling the max-vq set by sve-max-vq is not allowed, but + * of course enabling it is OK. + */ + assert_error(qts, "max", "cannot disable sve1024", "{ 'sve1024': false }"); + assert_sve_vls(qts, "max", 0xff, "{ 'sve1024': true }"); + + /* + * Enabling anything larger than max-vq set by sve-max-vq is not + * allowed, but of course disabling everything larger is OK. + */ + assert_error(qts, "max", "cannot enable sve1152", "{ 'sve1152': true }"); + assert_sve_vls(qts, "max", 0xff, "{ 'sve1152': false }"); + + /* + * We can enable/disable non power-of-two lengths smaller than the + * max-vq set by sve-max-vq, but, while we can enable power-of-two + * lengths, we can't disable them. + */ + assert_sve_vls(qts, "max", 0xff, "{ 'sve384': true }"); + assert_sve_vls(qts, "max", 0xfb, "{ 'sve384': false }"); + assert_sve_vls(qts, "max", 0xff, "{ 'sve256': true }"); + assert_error(qts, "max", "cannot disable sve256", "{ 'sve256': false }"); + + qtest_quit(qts); +} + +static void sve_tests_sve_off(const void *data) +{ + QTestState *qts; + + qts = qtest_init(MACHINE "-cpu max,sve=off"); + + /* SVE is off, so the map should be empty. */ + assert_sve_vls(qts, "max", 0, NULL); + + /* The map stays empty even if we turn lengths off. */ + assert_sve_vls(qts, "max", 0, "{ 'sve128': false }"); + + /* It's an error to enable lengths when SVE is off. */ + assert_error(qts, "max", "cannot enable sve128", "{ 'sve128': true }"); + + /* With SVE re-enabled we should get all vector lengths enabled. */ + assert_sve_vls(qts, "max", BIT_ULL(SVE_MAX_VQ) - 1, "{ 'sve': true }"); + + /* Or enable SVE with just specific vector lengths. */ + assert_sve_vls(qts, "max", 0x3, + "{ 'sve': true, 'sve128': true, 'sve256': true }"); + + qtest_quit(qts); +} + static void test_query_cpu_model_expansion(const void *data) { QTestState *qts; @@ -198,9 +382,12 @@ static void test_query_cpu_model_expansion(const void *data) if (g_str_equal(qtest_get_arch(), "aarch64")) { assert_has_feature(qts, "max", "aarch64"); assert_has_feature(qts, "max", "sve"); + assert_has_feature(qts, "max", "sve128"); assert_has_feature(qts, "cortex-a57", "pmu"); assert_has_feature(qts, "cortex-a57", "aarch64"); + sve_tests_default(qts, "max"); + /* Test that features that depend on KVM generate errors without. */ assert_error(qts, "max", "'aarch64' feature cannot be disabled " @@ -258,5 +445,12 @@ int main(int argc, char **argv) NULL, test_query_cpu_model_expansion_kvm); } + if (g_str_equal(qtest_get_arch(), "aarch64")) { + qtest_add_data_func("/arm/max/query-cpu-model-expansion/sve-max-vq-8", + NULL, sve_tests_sve_max_vq_8); + qtest_add_data_func("/arm/max/query-cpu-model-expansion/sve-off", + NULL, sve_tests_sve_off); + } + return g_test_run(); } |