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-rw-r--r--target/arm/cpu.h6
-rw-r--r--target/arm/cpu64.c117
-rw-r--r--target/arm/helper.c9
-rw-r--r--target/arm/internals.h5
-rw-r--r--target/arm/kvm64.c36
-rw-r--r--target/arm/kvm_arm.h7
6 files changed, 75 insertions, 105 deletions
diff --git a/target/arm/cpu.h b/target/arm/cpu.h
index f5af88b686..73f24a5760 100644
--- a/target/arm/cpu.h
+++ b/target/arm/cpu.h
@@ -1041,9 +1041,9 @@ struct ArchCPU {
      * Bits set in sve_vq_supported represent valid vector lengths for
      * the CPU type.
      */
-    DECLARE_BITMAP(sve_vq_map, ARM_MAX_VQ);
-    DECLARE_BITMAP(sve_vq_init, ARM_MAX_VQ);
-    DECLARE_BITMAP(sve_vq_supported, ARM_MAX_VQ);
+    uint32_t sve_vq_map;
+    uint32_t sve_vq_init;
+    uint32_t sve_vq_supported;
 
     /* Generic timer counter frequency, in Hz */
     uint64_t gt_cntfrq_hz;
diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c
index cce68dd82a..15665c962b 100644
--- a/target/arm/cpu64.c
+++ b/target/arm/cpu64.c
@@ -355,8 +355,11 @@ void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp)
      * 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;
+    uint32_t vq_map = cpu->sve_vq_map;
+    uint32_t vq_init = cpu->sve_vq_init;
+    uint32_t vq_supported;
+    uint32_t vq_mask = 0;
+    uint32_t tmp, vq, max_vq = 0;
 
     /*
      * CPU models specify a set of supported vector lengths which are
@@ -364,10 +367,16 @@ void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp)
      * in the supported bitmap results in an error.  When KVM is enabled we
      * fetch the supported bitmap from the host.
      */
-    if (kvm_enabled() && kvm_arm_sve_supported()) {
-        kvm_arm_sve_get_vls(CPU(cpu), cpu->sve_vq_supported);
-    } else if (kvm_enabled()) {
-        assert(!cpu_isar_feature(aa64_sve, cpu));
+    if (kvm_enabled()) {
+        if (kvm_arm_sve_supported()) {
+            cpu->sve_vq_supported = kvm_arm_sve_get_vls(CPU(cpu));
+            vq_supported = cpu->sve_vq_supported;
+        } else {
+            assert(!cpu_isar_feature(aa64_sve, cpu));
+            vq_supported = 0;
+        }
+    } else {
+        vq_supported = cpu->sve_vq_supported;
     }
 
     /*
@@ -375,8 +384,9 @@ void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp)
      * 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 (vq_map != 0) {
+        max_vq = 32 - clz32(vq_map);
+        vq_mask = MAKE_64BIT_MASK(0, max_vq);
 
         if (cpu->sve_max_vq && max_vq > cpu->sve_max_vq) {
             error_setg(errp, "cannot enable sve%d", max_vq * 128);
@@ -392,15 +402,10 @@ void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp)
              * For KVM we have to automatically enable all supported unitialized
              * lengths, even when the smaller lengths are not all powers-of-two.
              */
-            bitmap_andnot(tmp, cpu->sve_vq_supported, cpu->sve_vq_init, max_vq);
-            bitmap_or(cpu->sve_vq_map, cpu->sve_vq_map, tmp, max_vq);
+            vq_map |= vq_supported & ~vq_init & vq_mask;
         } else {
             /* 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);
-                }
-            }
+            vq_map |= SVE_VQ_POW2_MAP & ~vq_init & vq_mask;
         }
     } else if (cpu->sve_max_vq == 0) {
         /*
@@ -413,25 +418,18 @@ void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp)
 
         if (kvm_enabled()) {
             /* Disabling a supported length disables all larger lengths. */
-            for (vq = 1; vq <= ARM_MAX_VQ; ++vq) {
-                if (test_bit(vq - 1, cpu->sve_vq_init) &&
-                    test_bit(vq - 1, cpu->sve_vq_supported)) {
-                    break;
-                }
-            }
+            tmp = vq_init & vq_supported;
         } else {
             /* Disabling a power-of-two disables all larger lengths. */
-            for (vq = 1; vq <= ARM_MAX_VQ; vq <<= 1) {
-                if (test_bit(vq - 1, cpu->sve_vq_init)) {
-                    break;
-                }
-            }
+            tmp = vq_init & SVE_VQ_POW2_MAP;
         }
+        vq = ctz32(tmp) + 1;
 
         max_vq = vq <= ARM_MAX_VQ ? vq - 1 : ARM_MAX_VQ;
-        bitmap_andnot(cpu->sve_vq_map, cpu->sve_vq_supported,
-                      cpu->sve_vq_init, max_vq);
-        if (max_vq == 0 || bitmap_empty(cpu->sve_vq_map, max_vq)) {
+        vq_mask = MAKE_64BIT_MASK(0, max_vq);
+        vq_map = vq_supported & ~vq_init & vq_mask;
+
+        if (max_vq == 0 || vq_map == 0) {
             error_setg(errp, "cannot disable sve%d", vq * 128);
             error_append_hint(errp, "Disabling sve%d results in all "
                               "vector lengths being disabled.\n",
@@ -441,7 +439,8 @@ void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp)
             return;
         }
 
-        max_vq = find_last_bit(cpu->sve_vq_map, max_vq) + 1;
+        max_vq = 32 - clz32(vq_map);
+        vq_mask = MAKE_64BIT_MASK(0, max_vq);
     }
 
     /*
@@ -451,9 +450,9 @@ void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp)
      */
     if (cpu->sve_max_vq != 0) {
         max_vq = cpu->sve_max_vq;
+        vq_mask = MAKE_64BIT_MASK(0, max_vq);
 
-        if (!test_bit(max_vq - 1, cpu->sve_vq_map) &&
-            test_bit(max_vq - 1, cpu->sve_vq_init)) {
+        if (vq_init & ~vq_map & (1 << (max_vq - 1))) {
             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",
@@ -462,8 +461,7 @@ void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp)
         }
 
         /* 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);
+        vq_map |= ~vq_init & vq_mask;
     }
 
     /*
@@ -472,13 +470,14 @@ void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp)
      * are clear, just in case anybody looks.
      */
     assert(max_vq != 0);
-    bitmap_clear(cpu->sve_vq_map, max_vq, ARM_MAX_VQ - max_vq);
+    assert(vq_mask != 0);
+    vq_map &= vq_mask;
 
     /* Ensure the set of lengths matches what is supported. */
-    bitmap_xor(tmp, cpu->sve_vq_map, cpu->sve_vq_supported, max_vq);
-    if (!bitmap_empty(tmp, max_vq)) {
-        vq = find_last_bit(tmp, max_vq) + 1;
-        if (test_bit(vq - 1, cpu->sve_vq_map)) {
+    tmp = vq_map ^ (vq_supported & vq_mask);
+    if (tmp) {
+        vq = 32 - clz32(tmp);
+        if (vq_map & (1 << (vq - 1))) {
             if (cpu->sve_max_vq) {
                 error_setg(errp, "cannot set sve-max-vq=%d", cpu->sve_max_vq);
                 error_append_hint(errp, "This CPU does not support "
@@ -502,15 +501,15 @@ void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp)
                 return;
             } else {
                 /* 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;
-                    }
+                tmp = SVE_VQ_POW2_MAP & vq_mask & ~vq_map;
+                if (tmp) {
+                    vq = 32 - clz32(tmp);
+                    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;
                 }
             }
         }
@@ -530,6 +529,7 @@ void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp)
 
     /* From now on sve_max_vq is the actual maximum supported length. */
     cpu->sve_max_vq = max_vq;
+    cpu->sve_vq_map = vq_map;
 }
 
 static void cpu_max_get_sve_max_vq(Object *obj, Visitor *v, const char *name,
@@ -590,7 +590,7 @@ static void cpu_arm_get_sve_vq(Object *obj, Visitor *v, const char *name,
     if (!cpu_isar_feature(aa64_sve, cpu)) {
         value = false;
     } else {
-        value = test_bit(vq - 1, cpu->sve_vq_map);
+        value = extract32(cpu->sve_vq_map, vq - 1, 1);
     }
     visit_type_bool(v, name, &value, errp);
 }
@@ -612,12 +612,8 @@ static void cpu_arm_set_sve_vq(Object *obj, Visitor *v, const char *name,
         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);
+    cpu->sve_vq_map = deposit32(cpu->sve_vq_map, vq - 1, 1, value);
+    cpu->sve_vq_init |= 1 << (vq - 1);
 }
 
 static bool cpu_arm_get_sve(Object *obj, Error **errp)
@@ -979,7 +975,7 @@ static void aarch64_max_initfn(Object *obj)
     cpu->dcz_blocksize = 7; /*  512 bytes */
 #endif
 
-    bitmap_fill(cpu->sve_vq_supported, ARM_MAX_VQ);
+    cpu->sve_vq_supported = MAKE_64BIT_MASK(0, ARM_MAX_VQ);
 
     aarch64_add_pauth_properties(obj);
     aarch64_add_sve_properties(obj);
@@ -1026,12 +1022,11 @@ static void aarch64_a64fx_initfn(Object *obj)
     cpu->gic_vprebits = 5;
     cpu->gic_pribits = 5;
 
-    /* Suppport of A64FX's vector length are 128,256 and 512bit only */
+    /* The A64FX supports only 128, 256 and 512 bit vector lengths */
     aarch64_add_sve_properties(obj);
-    bitmap_zero(cpu->sve_vq_supported, ARM_MAX_VQ);
-    set_bit(0, cpu->sve_vq_supported); /* 128bit */
-    set_bit(1, cpu->sve_vq_supported); /* 256bit */
-    set_bit(3, cpu->sve_vq_supported); /* 512bit */
+    cpu->sve_vq_supported = (1 << 0)  /* 128bit */
+                          | (1 << 1)  /* 256bit */
+                          | (1 << 3); /* 512bit */
 
     cpu->isar.reset_pmcr_el0 = 0x46014040;
 
diff --git a/target/arm/helper.c b/target/arm/helper.c
index de159c644c..90aac6bc12 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -6219,7 +6219,6 @@ uint32_t sve_zcr_len_for_el(CPUARMState *env, int el)
 {
     ARMCPU *cpu = env_archcpu(env);
     uint32_t len = cpu->sve_max_vq - 1;
-    uint32_t end_len;
 
     if (el <= 1 && !el_is_in_host(env, el)) {
         len = MIN(len, 0xf & (uint32_t)env->vfp.zcr_el[1]);
@@ -6231,12 +6230,8 @@ uint32_t sve_zcr_len_for_el(CPUARMState *env, int el)
         len = MIN(len, 0xf & (uint32_t)env->vfp.zcr_el[3]);
     }
 
-    end_len = len;
-    if (!test_bit(len, cpu->sve_vq_map)) {
-        end_len = find_last_bit(cpu->sve_vq_map, len);
-        assert(end_len < len);
-    }
-    return end_len;
+    len = 31 - clz32(cpu->sve_vq_map & MAKE_64BIT_MASK(0, len + 1));
+    return len;
 }
 
 static void zcr_write(CPUARMState *env, const ARMCPRegInfo *ri,
diff --git a/target/arm/internals.h b/target/arm/internals.h
index 79eb463753..a1bae4588a 100644
--- a/target/arm/internals.h
+++ b/target/arm/internals.h
@@ -1340,4 +1340,9 @@ bool el_is_in_host(CPUARMState *env, int el);
 
 void aa32_max_features(ARMCPU *cpu);
 
+/* Powers of 2 for sve_vq_map et al. */
+#define SVE_VQ_POW2_MAP                                 \
+    ((1 << (1 - 1)) | (1 << (2 - 1)) |                  \
+     (1 << (4 - 1)) | (1 << (8 - 1)) | (1 << (16 - 1)))
+
 #endif
diff --git a/target/arm/kvm64.c b/target/arm/kvm64.c
index 363032da90..b3f635fc95 100644
--- a/target/arm/kvm64.c
+++ b/target/arm/kvm64.c
@@ -760,15 +760,13 @@ bool kvm_arm_steal_time_supported(void)
 
 QEMU_BUILD_BUG_ON(KVM_ARM64_SVE_VQ_MIN != 1);
 
-void kvm_arm_sve_get_vls(CPUState *cs, unsigned long *map)
+uint32_t kvm_arm_sve_get_vls(CPUState *cs)
 {
     /* Only call this function if kvm_arm_sve_supported() returns true. */
     static uint64_t vls[KVM_ARM64_SVE_VLS_WORDS];
     static bool probed;
     uint32_t vq = 0;
-    int i, j;
-
-    bitmap_zero(map, ARM_MAX_VQ);
+    int i;
 
     /*
      * KVM ensures all host CPUs support the same set of vector lengths.
@@ -809,46 +807,24 @@ void kvm_arm_sve_get_vls(CPUState *cs, unsigned long *map)
         if (vq > ARM_MAX_VQ) {
             warn_report("KVM supports vector lengths larger than "
                         "QEMU can enable");
+            vls[0] &= MAKE_64BIT_MASK(0, ARM_MAX_VQ);
         }
     }
 
-    for (i = 0; i < KVM_ARM64_SVE_VLS_WORDS; ++i) {
-        if (!vls[i]) {
-            continue;
-        }
-        for (j = 1; j <= 64; ++j) {
-            vq = j + i * 64;
-            if (vq > ARM_MAX_VQ) {
-                return;
-            }
-            if (vls[i] & (1UL << (j - 1))) {
-                set_bit(vq - 1, map);
-            }
-        }
-    }
+    return vls[0];
 }
 
 static int kvm_arm_sve_set_vls(CPUState *cs)
 {
-    uint64_t vls[KVM_ARM64_SVE_VLS_WORDS] = {0};
+    ARMCPU *cpu = ARM_CPU(cs);
+    uint64_t vls[KVM_ARM64_SVE_VLS_WORDS] = { cpu->sve_vq_map };
     struct kvm_one_reg reg = {
         .id = KVM_REG_ARM64_SVE_VLS,
         .addr = (uint64_t)&vls[0],
     };
-    ARMCPU *cpu = ARM_CPU(cs);
-    uint32_t vq;
-    int i, j;
 
     assert(cpu->sve_max_vq <= KVM_ARM64_SVE_VQ_MAX);
 
-    for (vq = 1; vq <= cpu->sve_max_vq; ++vq) {
-        if (test_bit(vq - 1, cpu->sve_vq_map)) {
-            i = (vq - 1) / 64;
-            j = (vq - 1) % 64;
-            vls[i] |= 1UL << j;
-        }
-    }
-
     return kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &reg);
 }
 
diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h
index b7f78b5215..99017b635c 100644
--- a/target/arm/kvm_arm.h
+++ b/target/arm/kvm_arm.h
@@ -239,13 +239,12 @@ bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf);
 /**
  * kvm_arm_sve_get_vls:
  * @cs: CPUState
- * @map: bitmap to fill in
  *
  * Get all the SVE vector lengths supported by the KVM host, setting
  * the bits corresponding to their length in quadwords minus one
- * (vq - 1) in @map up to ARM_MAX_VQ.
+ * (vq - 1) up to ARM_MAX_VQ.  Return the resulting map.
  */
-void kvm_arm_sve_get_vls(CPUState *cs, unsigned long *map);
+uint32_t kvm_arm_sve_get_vls(CPUState *cs);
 
 /**
  * kvm_arm_set_cpu_features_from_host:
@@ -439,7 +438,7 @@ static inline void kvm_arm_steal_time_finalize(ARMCPU *cpu, Error **errp)
     g_assert_not_reached();
 }
 
-static inline void kvm_arm_sve_get_vls(CPUState *cs, unsigned long *map)
+static inline uint32_t kvm_arm_sve_get_vls(CPUState *cs)
 {
     g_assert_not_reached();
 }