[PATCH 1/7] target/arm: Add ID_AA64ISAR2_EL1

[Peter Maydell]

From: Aaron Lindsay <aaron@os.amperecomputing.com>

Signed-off-by: Aaron Lindsay <aaron@os.amperecomputing.com>
[PMM: drop the HVF part of the patch and just comment that
 we need to do something when the register appears in that API]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 target/arm/cpu.h     | 1 +
 target/arm/helper.c  | 4 ++--
 target/arm/hvf/hvf.c | 1 +
 target/arm/kvm64.c   | 2 ++
 4 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/target/arm/cpu.h b/target/arm/cpu.h
index d50cd918580..e637796fd83 100644
--- a/target/arm/cpu.h
+++ b/target/arm/cpu.h
@@ -1033,6 +1033,7 @@ struct ArchCPU {
         uint32_t dbgdevid1;
         uint64_t id_aa64isar0;
         uint64_t id_aa64isar1;
+        uint64_t id_aa64isar2;
         uint64_t id_aa64pfr0;
         uint64_t id_aa64pfr1;
         uint64_t id_aa64mmfr0;
diff --git a/target/arm/helper.c b/target/arm/helper.c
index e3f5a7d2bdc..f9f7c3c39e9 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -8435,11 +8435,11 @@ void register_cp_regs_for_features(ARMCPU *cpu)
               .access = PL1_R, .type = ARM_CP_CONST,
               .accessfn = access_aa64_tid3,
               .resetvalue = cpu->isar.id_aa64isar1 },
-            { .name = "ID_AA64ISAR2_EL1_RESERVED", .state = ARM_CP_STATE_AA64,
+            { .name = "ID_AA64ISAR2_EL1", .state = ARM_CP_STATE_AA64,
               .opc0 = 3, .opc1 = 0, .crn = 0, .crm = 6, .opc2 = 2,
               .access = PL1_R, .type = ARM_CP_CONST,
               .accessfn = access_aa64_tid3,
-              .resetvalue = 0 },
+              .resetvalue = cpu->isar.id_aa64isar2 },
             { .name = "ID_AA64ISAR3_EL1_RESERVED", .state = ARM_CP_STATE_AA64,
               .opc0 = 3, .opc1 = 0, .crn = 0, .crm = 6, .opc2 = 3,
               .access = PL1_R, .type = ARM_CP_CONST,
diff --git a/target/arm/hvf/hvf.c b/target/arm/hvf/hvf.c
index 486f90be1d2..546c0e817f4 100644
--- a/target/arm/hvf/hvf.c
+++ b/target/arm/hvf/hvf.c
@@ -847,6 +847,7 @@ static bool 
hvf_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf)
         { HV_SYS_REG_ID_AA64DFR1_EL1, &host_isar.id_aa64dfr1 },
         { HV_SYS_REG_ID_AA64ISAR0_EL1, &host_isar.id_aa64isar0 },
         { HV_SYS_REG_ID_AA64ISAR1_EL1, &host_isar.id_aa64isar1 },
+        /* Add ID_AA64ISAR2_EL1 here when HVF supports it */
         { HV_SYS_REG_ID_AA64MMFR0_EL1, &host_isar.id_aa64mmfr0 },
         { HV_SYS_REG_ID_AA64MMFR1_EL1, &host_isar.id_aa64mmfr1 },
         { HV_SYS_REG_ID_AA64MMFR2_EL1, &host_isar.id_aa64mmfr2 },
diff --git a/target/arm/kvm64.c b/target/arm/kvm64.c
index 4d904a1d11b..ac440c33f9a 100644
--- a/target/arm/kvm64.c
+++ b/target/arm/kvm64.c
@@ -304,6 +304,8 @@ bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf)
                               ARM64_SYS_REG(3, 0, 0, 6, 0));
         err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64isar1,
                               ARM64_SYS_REG(3, 0, 0, 6, 1));
+        err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64isar2,
+                              ARM64_SYS_REG(3, 0, 0, 6, 2));
         err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64mmfr0,
                               ARM64_SYS_REG(3, 0, 0, 7, 0));
         err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64mmfr1,
-- 
2.34.1