target/arm: Implement Neoverse N2 CPU model

Implement a model of the Neoverse N2 CPU. This is an Armv9.0-A
processor very similar to the Cortex-A710. The differences are:
 * no FEAT_EVT
 * FEAT_DGH (data gathering hint)
 * FEAT_NV (not yet implemented in QEMU)
 * Statistical Profiling Extension (not implemented in QEMU)
 * 48 bit physical address range, not 40
 * CTR_EL0.DIC = 1 (no explicit icache cleaning needed)
 * PMCR_EL0.N = 6 (always 6 PMU counters, not 20)

Because it has 48-bit physical address support, we can use
this CPU in the sbsa-ref board as well as the virt board.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Marcin Juszkiewicz <marcin.juszkiewicz@linaro.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20230915185453.1871167-3-peter.maydell@linaro.org

docs/system/arm/virt.rst

@@ -63,6 +63,7 @@ Supported guest CPU types:
 - ``host`` (with KVM only)
 - ``neoverse-n1`` (64-bit)
 - ``neoverse-v1`` (64-bit)
+- ``neoverse-n2`` (64-bit)
 - ``max`` (same as ``host`` for KVM; best possible emulation with TCG)
 
 Note that the default is ``cortex-a15``, so for an AArch64 guest you must

hw/arm/sbsa-ref.c

@@ -149,6 +149,7 @@ static const char * const valid_cpus[] = {
     ARM_CPU_TYPE_NAME("cortex-a72"),
     ARM_CPU_TYPE_NAME("neoverse-n1"),
     ARM_CPU_TYPE_NAME("neoverse-v1"),
+    ARM_CPU_TYPE_NAME("neoverse-n2"),
     ARM_CPU_TYPE_NAME("max"),
 };
 

hw/arm/virt.c

@@ -215,6 +215,7 @@ static const char *valid_cpus[] = {
     ARM_CPU_TYPE_NAME("a64fx"),
     ARM_CPU_TYPE_NAME("neoverse-n1"),
     ARM_CPU_TYPE_NAME("neoverse-v1"),
+    ARM_CPU_TYPE_NAME("neoverse-n2"),
 #endif
     ARM_CPU_TYPE_NAME("cortex-a53"),
     ARM_CPU_TYPE_NAME("cortex-a57"),

target/arm/tcg/cpu64.c

@@ -963,6 +963,108 @@ static void aarch64_a710_initfn(Object *obj)
     aarch64_add_sve_properties(obj);
 }
 
+/* Extra IMPDEF regs in the N2 beyond those in the A710 */
+static const ARMCPRegInfo neoverse_n2_cp_reginfo[] = {
+    { .name = "CPURNDBR_EL3", .state = ARM_CP_STATE_AA64,
+      .opc0 = 3, .opc1 = 6, .crn = 15, .crm = 3, .opc2 = 0,
+      .access = PL3_RW, .type = ARM_CP_CONST, .resetvalue = 0 },
+    { .name = "CPURNDPEID_EL3", .state = ARM_CP_STATE_AA64,
+      .opc0 = 3, .opc1 = 6, .crn = 15, .crm = 3, .opc2 = 1,
+      .access = PL3_RW, .type = ARM_CP_CONST, .resetvalue = 0 },
+};
+
+static void aarch64_neoverse_n2_initfn(Object *obj)
+{
+    ARMCPU *cpu = ARM_CPU(obj);
+
+    cpu->dtb_compatible = "arm,neoverse-n2";
+    set_feature(&cpu->env, ARM_FEATURE_V8);
+    set_feature(&cpu->env, ARM_FEATURE_NEON);
+    set_feature(&cpu->env, ARM_FEATURE_GENERIC_TIMER);
+    set_feature(&cpu->env, ARM_FEATURE_AARCH64);
+    set_feature(&cpu->env, ARM_FEATURE_CBAR_RO);
+    set_feature(&cpu->env, ARM_FEATURE_EL2);
+    set_feature(&cpu->env, ARM_FEATURE_EL3);
+    set_feature(&cpu->env, ARM_FEATURE_PMU);
+
+    /* Ordered by Section B.5: AArch64 ID registers */
+    cpu->midr          = 0x410FD493; /* r0p3 */
+    cpu->revidr        = 0;
+    cpu->isar.id_pfr0  = 0x21110131;
+    cpu->isar.id_pfr1  = 0x00010000; /* GIC filled in later */
+    cpu->isar.id_dfr0  = 0x16011099;
+    cpu->id_afr0       = 0;
+    cpu->isar.id_mmfr0 = 0x10201105;
+    cpu->isar.id_mmfr1 = 0x40000000;
+    cpu->isar.id_mmfr2 = 0x01260000;
+    cpu->isar.id_mmfr3 = 0x02122211;
+    cpu->isar.id_isar0 = 0x02101110;
+    cpu->isar.id_isar1 = 0x13112111;
+    cpu->isar.id_isar2 = 0x21232042;
+    cpu->isar.id_isar3 = 0x01112131;
+    cpu->isar.id_isar4 = 0x00010142;
+    cpu->isar.id_isar5 = 0x11011121; /* with Crypto */
+    cpu->isar.id_mmfr4 = 0x01021110;
+    cpu->isar.id_isar6 = 0x01111111;
+    cpu->isar.mvfr0    = 0x10110222;
+    cpu->isar.mvfr1    = 0x13211111;
+    cpu->isar.mvfr2    = 0x00000043;
+    cpu->isar.id_pfr2  = 0x00000011;
+    cpu->isar.id_aa64pfr0  = 0x1201111120111112ull; /* GIC filled in later */
+    cpu->isar.id_aa64pfr1  = 0x0000000000000221ull;
+    cpu->isar.id_aa64zfr0  = 0x0000110100110021ull; /* with Crypto */
+    cpu->isar.id_aa64dfr0  = 0x000011f210305619ull;
+    cpu->isar.id_aa64dfr1  = 0;
+    cpu->id_aa64afr0       = 0;
+    cpu->id_aa64afr1       = 0;
+    cpu->isar.id_aa64isar0 = 0x0221111110212120ull; /* with Crypto */
+    cpu->isar.id_aa64isar1 = 0x0011111101211052ull;
+    cpu->isar.id_aa64mmfr0 = 0x0000022200101125ull;
+    cpu->isar.id_aa64mmfr1 = 0x0000000010212122ull;
+    cpu->isar.id_aa64mmfr2 = 0x1221011112101011ull;
+    cpu->clidr             = 0x0000001482000023ull;
+    cpu->gm_blocksize      = 4;
+    cpu->ctr               = 0x00000004b444c004ull;
+    cpu->dcz_blocksize     = 4;
+    /* TODO FEAT_MPAM: mpamidr_el1 = 0x0000_0001_001e_01ff */
+
+    /* Section B.7.2: PMCR_EL0 */
+    cpu->isar.reset_pmcr_el0 = 0x3000;  /* with 6 counters */
+
+    /* Section B.8.9: ICH_VTR_EL2 */
+    cpu->gic_num_lrs = 4;
+    cpu->gic_vpribits = 5;
+    cpu->gic_vprebits = 5;
+    cpu->gic_pribits = 5;
+
+    /* Section 14: Scalable Vector Extensions support */
+    cpu->sve_vq.supported = 1 << 0;  /* 128bit */
+
+    /*
+     * The Neoverse N2 TRM does not list CCSIDR values.  The layout of
+     * the caches are in text in Table 7-1, Table 8-1, and Table 9-1.
+     *
+     * L1: 4-way set associative 64-byte line size, total 64K.
+     * L2: 8-way set associative 64 byte line size, total either 512K or 1024K.
+     */
+    cpu->ccsidr[0] = make_ccsidr64(4, 64, 64 * KiB);   /* L1 dcache */
+    cpu->ccsidr[1] = cpu->ccsidr[0];                   /* L1 icache */
+    cpu->ccsidr[2] = make_ccsidr64(8, 64, 512 * KiB);  /* L2 cache */
+
+    /* FIXME: Not documented -- copied from neoverse-v1 */
+    cpu->reset_sctlr = 0x30c50838;
+
+    /*
+     * The Neoverse N2 has all of the Cortex-A710 IMPDEF registers,
+     * and a few more RNG related ones.
+     */
+    define_arm_cp_regs(cpu, cortex_a710_cp_reginfo);
+    define_arm_cp_regs(cpu, neoverse_n2_cp_reginfo);
+
+    aarch64_add_pauth_properties(obj);
+    aarch64_add_sve_properties(obj);
+}
+
 /*
  * -cpu max: a CPU with as many features enabled as our emulation supports.
  * The version of '-cpu max' for qemu-system-arm is defined in cpu32.c;
@@ -1165,6 +1267,7 @@ static const ARMCPUInfo aarch64_cpus[] = {
     { .name = "a64fx",              .initfn = aarch64_a64fx_initfn },
     { .name = "neoverse-n1",        .initfn = aarch64_neoverse_n1_initfn },
     { .name = "neoverse-v1",        .initfn = aarch64_neoverse_v1_initfn },
+    { .name = "neoverse-n2",        .initfn = aarch64_neoverse_n2_initfn },
 };
 
 static void aarch64_cpu_register_types(void)