@@ -310,7 +310,7 @@ static void cpu_set_sve_vls_map(Object *obj, Visitor *v, const char *name,
error_setg(&err, "SVE vector length map has unsupported lengths");
error_append_hint(&err, "Valid vector lengths in range [1-%d]\n",
ARM_MAX_VQ);
- } else if (cpu->sve_max_vq != ARM_MAX_VQ &&
+ } else if (cpu->sve_max_vq != ARM_MAX_VQ && cpu->sve_max_vq != -1 &&
cpu->sve_max_vq != arm_cpu_fls64(cpu->sve_vls_map)) {
/*
* If the user provides both sve-max-vq and sve-vls-map, with
@@ -433,13 +433,12 @@ static void aarch64_max_initfn(Object *obj)
#endif
cpu->sve_max_vq = ARM_MAX_VQ;
-
- object_property_add(obj, "sve-vls-map", "uint64", cpu_get_sve_vls_map,
- cpu_set_sve_vls_map, NULL, NULL, &error_fatal);
}
object_property_add(obj, "sve-max-vq", "uint32", cpu_max_get_sve_vq,
cpu_max_set_sve_vq, NULL, NULL, &error_fatal);
+ object_property_add(obj, "sve-vls-map", "uint64", cpu_get_sve_vls_map,
+ cpu_set_sve_vls_map, NULL, NULL, &error_fatal);
}
struct ARMCPUInfo {
@@ -685,9 +685,9 @@ int kvm_arch_init_vcpu(CPUState *cs)
} else {
unset_feature(&env->features, ARM_FEATURE_PMU);
}
- if (cpu->sve_max_vq) {
+ if (cpu->sve_max_vq || cpu->sve_vls_map) {
if (!kvm_check_extension(cs->kvm_state, KVM_CAP_ARM_SVE)) {
- if (cpu->sve_max_vq == -1) {
+ if (cpu->sve_max_vq == -1 && !cpu->sve_vls_map) {
cpu->sve_max_vq = 0;
} else {
error_report("This KVM host does not support SVE");
@@ -704,12 +704,62 @@ int kvm_arch_init_vcpu(CPUState *cs)
return ret;
}
- if (cpu->sve_max_vq) {
+ if (cpu->sve_max_vq || cpu->sve_vls_map) {
uint64_t sve_vls[KVM_ARM64_SVE_VLS_WORDS];
ret = kvm_arm_get_sve_vls(cs, sve_vls);
if (ret < 0) {
return ret;
}
+ if (cpu->sve_vls_map) {
+ uint64_t ovls;
+ int i;
+
+ /*
+ * We currently only support a single VLS word, as that should
+ * be sufficient for some time (vq=64 means a 8192-bit vector
+ * and KVM currently only supports up to 2048-bit vectors).
+ * The choice to only support a single word for now is due to
+ * the need to input it on the command line. It's much simpler
+ * to input a word as a cpu property than an array of words.
+ * So for now just warn if we detect our assumption was wrong.
+ */
+ for (i = 1; i < KVM_ARM64_SVE_VLS_WORDS; ++i) {
+ if (sve_vls[i]) {
+ warn_report("KVM supports vector lengths larger than "
+ "sve-vls-map can select");
+ sve_vls[i] = 0;
+ }
+ }
+
+ ovls = sve_vls[0];
+ sve_vls[0] = cpu->sve_vls_map;
+
+ if (cpu->sve_vls_map & ~ovls) {
+ error_report("sve-vls-map=0x%lx is not valid on this host "
+ "which supports 0x%lx", cpu->sve_vls_map, ovls);
+ return -EINVAL;
+ }
+
+ i = arm_cpu_fls64(cpu->sve_vls_map);
+ if (cpu->sve_max_vq && cpu->sve_max_vq != -1 &&
+ cpu->sve_max_vq != i) {
+ error_report("sve-vls-map and sve-max-vq are inconsistent");
+ return -EINVAL;
+ }
+ cpu->sve_max_vq = i;
+
+ /*
+ * sve-vls-map must have all the same vector lengths up to its
+ * max vq that the host supports.
+ */
+ if (cpu->sve_vls_map != (ovls & (BIT_MASK(cpu->sve_max_vq) - 1))) {
+ error_report("sve-vls-map=0x%lx is not valid on this host "
+ "which supports 0x%lx", cpu->sve_vls_map, ovls);
+ error_printf("All host vector lengths up to %d must also "
+ "be selected.\n", cpu->sve_max_vq);
+ return -EINVAL;
+ }
+ }
if (cpu->sve_max_vq == -1) {
cpu->sve_max_vq = ret;
} else if (cpu->sve_max_vq > ret) {
The max cpu type can have its SVE vector lengths explicitly set with the sve-vls-map property. This patch allows that property to work when KVM is in use. The map must conform to additional constraints for KVM which are checked at vcpu init. Signed-off-by: Andrew Jones <drjones@redhat.com> --- target/arm/cpu64.c | 7 +++--- target/arm/kvm64.c | 56 +++++++++++++++++++++++++++++++++++++++++++--- 2 files changed, 56 insertions(+), 7 deletions(-)