[PATCH v3 8/8] target/arm: Add CPU property for QARMA3, enable FPACCombined by default

[Aaron Lindsay <aaron@os.amperecomputing.com>]

Signed-off-by: Aaron Lindsay <aaron@os.amperecomputing.com>
---
 target/arm/cpu.h   |  1 +
 target/arm/cpu64.c | 48 +++++++++++++++++++++++++++++++---------------
 2 files changed, 34 insertions(+), 15 deletions(-)

diff --git a/target/arm/cpu.h b/target/arm/cpu.h
index 868d844d5a..80683c428f 100644
--- a/target/arm/cpu.h
+++ b/target/arm/cpu.h
@@ -1053,6 +1053,7 @@ struct ArchCPU {
      */
     bool prop_pauth;
     bool prop_pauth_impdef;
+    bool prop_pauth_qarma3;
     bool prop_lpa2;
 
     /* DCZ blocksize, in log_2(words), ie low 4 bits of DCZID_EL0 */
diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c
index 0fb07cc7b6..a5f4540c73 100644
--- a/target/arm/cpu64.c
+++ b/target/arm/cpu64.c
@@ -591,9 +591,6 @@ static void aarch64_add_sme_properties(Object *obj)
 
 void arm_cpu_pauth_finalize(ARMCPU *cpu, Error **errp)
 {
-    int arch_val = 0, impdef_val = 0;
-    uint64_t t;
-
     /* Exit early if PAuth is enabled, and fall through to disable it */
     if ((kvm_enabled() || hvf_enabled()) && cpu->prop_pauth) {
         if (!cpu_isar_feature(aa64_pauth, cpu)) {
@@ -604,30 +601,50 @@ void arm_cpu_pauth_finalize(ARMCPU *cpu, Error **errp)
         return;
     }
 
-    /* TODO: Handle HaveEnhancedPAC, HaveEnhancedPAC2, HaveFPAC. */
+    /* Write the features into the correct field for the algorithm in use */
     if (cpu->prop_pauth) {
+        uint64_t t;
+
+        if (cpu->prop_pauth_impdef && cpu->prop_pauth_qarma3) {
+            error_setg(errp, "Cannot set both qarma3 ('pauth-qarma3') and "
+                    "impdef ('pauth-impdef') pointer authentication ciphers");
+            return;
+        }
+
+        /* Implement FEAT_FPACCOMBINE for address authentication and enable
+         * generic authentication for the chosen cipher.
+         */
+        int address_auth = 0b0101;
+        int generic_auth = 0b0001;
+
         if (cpu->prop_pauth_impdef) {
-            impdef_val = 1;
+            t = cpu->isar.id_aa64isar1;
+            t = FIELD_DP64(t, ID_AA64ISAR1, API, address_auth);
+            t = FIELD_DP64(t, ID_AA64ISAR1, GPI, generic_auth);
+            cpu->isar.id_aa64isar1 = t;
+        } else if (cpu->prop_pauth_qarma3) {
+            t = cpu->isar.id_aa64isar2;
+            t = FIELD_DP64(t, ID_AA64ISAR2, APA3, address_auth);
+            t = FIELD_DP64(t, ID_AA64ISAR2, GPA3, generic_auth);
+            cpu->isar.id_aa64isar2 = t;
         } else {
-            arch_val = 1;
+            t = cpu->isar.id_aa64isar1;
+            t = FIELD_DP64(t, ID_AA64ISAR1, APA, address_auth);
+            t = FIELD_DP64(t, ID_AA64ISAR1, GPA, generic_auth);
+            cpu->isar.id_aa64isar1 = t;
         }
-    } else if (cpu->prop_pauth_impdef) {
-        error_setg(errp, "cannot enable pauth-impdef without pauth");
+    } else if (cpu->prop_pauth_impdef || cpu->prop_pauth_qarma3) {
+        error_setg(errp, "cannot enable pauth-impdef or pauth-qarma3 without pauth");
         error_append_hint(errp, "Add pauth=on to the CPU property list.\n");
     }
-
-    t = cpu->isar.id_aa64isar1;
-    t = FIELD_DP64(t, ID_AA64ISAR1, APA, arch_val);
-    t = FIELD_DP64(t, ID_AA64ISAR1, GPA, arch_val);
-    t = FIELD_DP64(t, ID_AA64ISAR1, API, impdef_val);
-    t = FIELD_DP64(t, ID_AA64ISAR1, GPI, impdef_val);
-    cpu->isar.id_aa64isar1 = t;
 }
 
 static Property arm_cpu_pauth_property =
     DEFINE_PROP_BOOL("pauth", ARMCPU, prop_pauth, true);
 static Property arm_cpu_pauth_impdef_property =
     DEFINE_PROP_BOOL("pauth-impdef", ARMCPU, prop_pauth_impdef, false);
+static Property arm_cpu_pauth_qarma3_property =
+    DEFINE_PROP_BOOL("pauth-qarma3", ARMCPU, prop_pauth_qarma3, false);
 
 static void aarch64_add_pauth_properties(Object *obj)
 {
@@ -647,6 +664,7 @@ static void aarch64_add_pauth_properties(Object *obj)
         cpu->prop_pauth = cpu_isar_feature(aa64_pauth, cpu);
     } else {
         qdev_property_add_static(DEVICE(obj), &arm_cpu_pauth_impdef_property);
+        qdev_property_add_static(DEVICE(obj), &arm_cpu_pauth_qarma3_property);
     }
 }
 
-- 
2.25.1