[PATCH 0/2] target/arm: Implement Neoverse-N2

[PATCH 0/2] target/arm: Implement Neoverse-N2

[Peter Maydell]

This patchset implements a model of the Neoverse-N2 CPU.
Because it's very similar to the Cortex-A710 we don't
need to implement any new features for it; but because it
supports 48 bit physical addresses we can use it in the
sbsa-ref board.

Patch 1 fixes a few minor errors in the A710 definition
that I spotted while I was cross-checking it against the
N2 TRM to see what had changed.

Patch 2 is the new CPU model.

thanks
-- PMM

Peter Maydell (2):
  target/arm: Correct minor errors in Cortex-A710 definition
  target/arm: Implement Neoverse N2 CPU model

 docs/system/arm/virt.rst |   1 +
 hw/arm/sbsa-ref.c        |   1 +
 hw/arm/virt.c            |   1 +
 target/arm/tcg/cpu64.c   | 114 ++++++++++++++++++++++++++++++++++++++-
 4 files changed, 115 insertions(+), 2 deletions(-)

-- 
2.34.1

[PATCH 1/2] target/arm: Correct minor errors in Cortex-A710 definition

[Peter Maydell]

Correct a couple of minor errors in the Cortex-A710 definition:
 * ID_AA64DFR0_EL1.DebugVer is 9 (indicating Armv8.4 debug architecture)
 * ID_AA64ISAR1_EL1.APA is 5 (indicating more PAuth support)
 * there is an IMPDEF CPUCFR_EL1, like that on the Neoverse-N1

Fixes: e3d45c0a89576 ("target/arm: Implement cortex-a710")
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
---
 target/arm/tcg/cpu64.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/target/arm/tcg/cpu64.c b/target/arm/tcg/cpu64.c
index 7264ab5ead1..ea43cf3c1ee 100644
--- a/target/arm/tcg/cpu64.c
+++ b/target/arm/tcg/cpu64.c
@@ -840,6 +840,13 @@ static const ARMCPRegInfo cortex_a710_cp_reginfo[] = {
     { .name = "CPUPFR_EL3", .state = ARM_CP_STATE_AA64,
       .opc0 = 3, .opc1 = 6, .crn = 15, .crm = 8, .opc2 = 6,
       .access = PL3_RW, .type = ARM_CP_CONST, .resetvalue = 0 },
+    /*
+     * Report CPUCFR_EL1.SCU as 1, as we do not implement the DSU
+     * (and in particular its system registers).
+     */
+    { .name = "CPUCFR_EL1", .state = ARM_CP_STATE_AA64,
+      .opc0 = 3, .opc1 = 0, .crn = 15, .crm = 0, .opc2 = 0,
+      .access = PL1_R, .type = ARM_CP_CONST, .resetvalue = 4 },
 
     /*
      * Stub RAMINDEX, as we don't actually implement caches, BTB,
@@ -909,12 +916,12 @@ static void aarch64_a710_initfn(Object *obj)
     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  = 0x000011f010305611ull;
+    cpu->isar.id_aa64dfr0  = 0x000011f010305619ull;
     cpu->isar.id_aa64dfr1  = 0;
     cpu->id_aa64afr0       = 0;
     cpu->id_aa64afr1       = 0;
     cpu->isar.id_aa64isar0 = 0x0221111110212120ull; /* with Crypto */
-    cpu->isar.id_aa64isar1 = 0x0010111101211032ull;
+    cpu->isar.id_aa64isar1 = 0x0010111101211052ull;
     cpu->isar.id_aa64mmfr0 = 0x0000022200101122ull;
     cpu->isar.id_aa64mmfr1 = 0x0000000010212122ull;
     cpu->isar.id_aa64mmfr2 = 0x1221011110101011ull;
-- 
2.34.1

[PATCH 2/2] target/arm: Implement Neoverse N2 CPU model

[Peter Maydell]

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>
---
 docs/system/arm/virt.rst |   1 +
 hw/arm/sbsa-ref.c        |   1 +
 hw/arm/virt.c            |   1 +
 target/arm/tcg/cpu64.c   | 103 +++++++++++++++++++++++++++++++++++++++
 4 files changed, 106 insertions(+)

diff --git a/docs/system/arm/virt.rst b/docs/system/arm/virt.rst
index e1697ac8f48..7c4c80180c6 100644
--- a/docs/system/arm/virt.rst
+++ b/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
diff --git a/hw/arm/sbsa-ref.c b/hw/arm/sbsa-ref.c
index bc89eb48062..4db287287e1 100644
--- a/hw/arm/sbsa-ref.c
+++ b/hw/arm/sbsa-ref.c
@@ -154,6 +154,7 @@ 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"),
 };
 
diff --git a/hw/arm/virt.c b/hw/arm/virt.c
index 8ad78b23c24..42253462735 100644
--- a/hw/arm/virt.c
+++ b/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"),
diff --git a/target/arm/tcg/cpu64.c b/target/arm/tcg/cpu64.c
index ea43cf3c1ee..370cc82f0ef 100644
--- a/target/arm/tcg/cpu64.c
+++ b/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;
@@ -1159,6 +1261,7 @@ 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)
-- 
2.34.1

Re: [PATCH 0/2] target/arm: Implement Neoverse-N2

[Marcin Juszkiewicz]

W dniu 15.09.2023 o 20:54, Peter Maydell pisze:
> This patchset implements a model of the Neoverse-N2 CPU.
> Because it's very similar to the Cortex-A710 we don't
> need to implement any new features for it; but because it
> supports 48 bit physical addresses we can use it in the
> sbsa-ref board.
> 
> Patch 1 fixes a few minor errors in the A710 definition
> that I spotted while I was cross-checking it against the
> N2 TRM to see what had changed.
> 
> Patch 2 is the new CPU model.

Tested-by: Marcin Juszkiewicz <marcin.juszkiewicz@linaro.org>

root@sbsa-ref:~# lscpu
Architecture:           aarch64
   CPU op-mode(s):       32-bit, 64-bit
   Byte Order:           Little Endian
CPU(s):                 2
   On-line CPU(s) list:  0,1
Vendor ID:              ARM
   BIOS Vendor ID:       QEMU
   Model name:           Neoverse-N2

Re: [PATCH 0/2] target/arm: Implement Neoverse-N2

[Peter Maydell]

Ping for code review -- Richard or Alex, maybe ?

thanks
-- PMM

On Fri, 15 Sept 2023 at 19:54, Peter Maydell <peter.maydell@linaro.org> wrote:
>
> This patchset implements a model of the Neoverse-N2 CPU.
> Because it's very similar to the Cortex-A710 we don't
> need to implement any new features for it; but because it
> supports 48 bit physical addresses we can use it in the
> sbsa-ref board.
>
> Patch 1 fixes a few minor errors in the A710 definition
> that I spotted while I was cross-checking it against the
> N2 TRM to see what had changed.
>
> Patch 2 is the new CPU model.
>
> thanks
> -- PMM
>
> Peter Maydell (2):
>   target/arm: Correct minor errors in Cortex-A710 definition
>   target/arm: Implement Neoverse N2 CPU model
>
>  docs/system/arm/virt.rst |   1 +
>  hw/arm/sbsa-ref.c        |   1 +
>  hw/arm/virt.c            |   1 +
>  target/arm/tcg/cpu64.c   | 114 ++++++++++++++++++++++++++++++++++++++-
>  4 files changed, 115 insertions(+), 2 deletions(-)

Re: [PATCH 1/2] target/arm: Correct minor errors in Cortex-A710 definition

[Alex Bennée]

Peter Maydell <peter.maydell@linaro.org> writes:

> Correct a couple of minor errors in the Cortex-A710 definition:
>  * ID_AA64DFR0_EL1.DebugVer is 9 (indicating Armv8.4 debug architecture)
>  * ID_AA64ISAR1_EL1.APA is 5 (indicating more PAuth support)
>  * there is an IMPDEF CPUCFR_EL1, like that on the Neoverse-N1
>
> Fixes: e3d45c0a89576 ("target/arm: Implement cortex-a710")
> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>

-- 
Alex Bennée
Virtualisation Tech Lead @ Linaro

Re: [PATCH 2/2] target/arm: Implement Neoverse N2 CPU model

[Alex Bennée]

Peter Maydell <peter.maydell@linaro.org> writes:

> 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>
> ---
>  docs/system/arm/virt.rst |   1 +
>  hw/arm/sbsa-ref.c        |   1 +
>  hw/arm/virt.c            |   1 +
>  target/arm/tcg/cpu64.c   | 103 +++++++++++++++++++++++++++++++++++++++
>  4 files changed, 106 insertions(+)
>
> diff --git a/docs/system/arm/virt.rst b/docs/system/arm/virt.rst
> index e1697ac8f48..7c4c80180c6 100644
> --- a/docs/system/arm/virt.rst
> +++ b/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
> diff --git a/hw/arm/sbsa-ref.c b/hw/arm/sbsa-ref.c
> index bc89eb48062..4db287287e1 100644
> --- a/hw/arm/sbsa-ref.c
> +++ b/hw/arm/sbsa-ref.c
> @@ -154,6 +154,7 @@ 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"),
>  };
>  
> diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> index 8ad78b23c24..42253462735 100644
> --- a/hw/arm/virt.c
> +++ b/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"),
> diff --git a/target/arm/tcg/cpu64.c b/target/arm/tcg/cpu64.c
> index ea43cf3c1ee..370cc82f0ef 100644
> --- a/target/arm/tcg/cpu64.c
> +++ b/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 */

Jonathan mentioned he was hacking about with MPAM so if there is a stub
implementation of the fields it would be nice to add them.

> +
> +    /* 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;

Hmm reset_sctlr might need to be bigger because being used for sctlr_el3
is a 64 bit entity which has a number of fields:

  - DSSBS,bit[44] to have some sort of impdef value
  - the others all look like architecturally UNKNOWN values

Otherwise I think this is:

  - 3 - RES1 29:28
  - 0 - RES0 + I assume LE EE bit
  - c - RES1 23, EIS 22 (architecturally UNKNOWN on reset)
  - 5 - RES1 18, 16
  - 0 - RES0 15:14, EnDB 13 (architecturally UNKNOWN on reset), I 12 RES0
  - 8 - EOS 11 (architecturally UNKNOWN on reset)
  - 3 - RES1 5:4
  - 8 - SA 3 (architecturally UNKNOWN on reset)

It's a little confusing because the language describing these
architecturally unknown states refers to resetting to EL3 (I assume a
decent firmware would make sure everything is set correctly). Which
makes me wonder if reset_sctlr is really "sane values for a direct
kernel boot"?

> +
> +    /*
> +     * 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;
> @@ -1159,6 +1261,7 @@ 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)


-- 
Alex Bennée
Virtualisation Tech Lead @ Linaro

Re: [PATCH 2/2] target/arm: Implement Neoverse N2 CPU model

[Peter Maydell]

On Tue, 17 Oct 2023 at 14:50, Alex Bennée <alex.bennee@linaro.org> wrote:
>
>
> Peter Maydell <peter.maydell@linaro.org> writes:
>
> > 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>
> > ---
> >  docs/system/arm/virt.rst |   1 +
> >  hw/arm/sbsa-ref.c        |   1 +
> >  hw/arm/virt.c            |   1 +
> >  target/arm/tcg/cpu64.c   | 103 +++++++++++++++++++++++++++++++++++++++
> >  4 files changed, 106 insertions(+)
> >
> > diff --git a/docs/system/arm/virt.rst b/docs/system/arm/virt.rst
> > index e1697ac8f48..7c4c80180c6 100644
> > --- a/docs/system/arm/virt.rst
> > +++ b/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
> > diff --git a/hw/arm/sbsa-ref.c b/hw/arm/sbsa-ref.c
> > index bc89eb48062..4db287287e1 100644
> > --- a/hw/arm/sbsa-ref.c
> > +++ b/hw/arm/sbsa-ref.c
> > @@ -154,6 +154,7 @@ 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"),
> >  };
> >
> > diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> > index 8ad78b23c24..42253462735 100644
> > --- a/hw/arm/virt.c
> > +++ b/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"),
> > diff --git a/target/arm/tcg/cpu64.c b/target/arm/tcg/cpu64.c
> > index ea43cf3c1ee..370cc82f0ef 100644
> > --- a/target/arm/tcg/cpu64.c
> > +++ b/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 */
>
> Jonathan mentioned he was hacking about with MPAM so if there is a stub
> implementation of the fields it would be nice to add them.

I'm just following the existing A710 code here. There isn't
a stub implementation of the fields, which is why there's
just a TODO comment documenting the ID register value.

> > +
> > +    /* 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;
>
> Hmm reset_sctlr might need to be bigger because being used for sctlr_el3
> is a 64 bit entity which has a number of fields:

In theory, yes. In practice, only if we get to a point where we
want to set some bit in the top 32 bits, which we don't yet.

>
>   - DSSBS,bit[44] to have some sort of impdef value
>   - the others all look like architecturally UNKNOWN values
>
> Otherwise I think this is:
>
>   - 3 - RES1 29:28
>   - 0 - RES0 + I assume LE EE bit
>   - c - RES1 23, EIS 22 (architecturally UNKNOWN on reset)
>   - 5 - RES1 18, 16
>   - 0 - RES0 15:14, EnDB 13 (architecturally UNKNOWN on reset), I 12 RES0
>   - 8 - EOS 11 (architecturally UNKNOWN on reset)
>   - 3 - RES1 5:4
>   - 8 - SA 3 (architecturally UNKNOWN on reset)
>
> It's a little confusing because the language describing these
> architecturally unknown states refers to resetting to EL3 (I assume a
> decent firmware would make sure everything is set correctly). Which
> makes me wonder if reset_sctlr is really "sane values for a direct
> kernel boot"?

It's the hardware reset value, at least nominally speaking.
We use the value for our SCTLR_EL1 if we aren't emulating EL2 or EL3,
which means we diverge a little from the hardware which probably doesn't
support an EL1-only config.

To the extent that we need to set values here for kernel boot, we would
do that in hw/arm/boot.c. But mostly we don't, because the kernel sets
up the SCTLR register for the EL it is entered in.

This used to be a bit better defined on older CPUs when previous
versions of the architecture weren't so loose about values being
UNKNOWN on reset. It's unfortunate that we don't have the documented
value for whatever the IMPDEF reset value is for this CPU. In
practice, because it's IMPDEF and UNKNOWN it doesn't matter too much --
guest software will set it as needed. The value used here is "safe"
because it's one we already use for other CPUs.

> > +
> > +    /*
> > +     * 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;
> > @@ -1159,6 +1261,7 @@ 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)

thanks
-- PMM

Re: [PATCH 2/2] target/arm: Implement Neoverse N2 CPU model

[Alex Bennée]

Peter Maydell <peter.maydell@linaro.org> writes:

> On Tue, 17 Oct 2023 at 14:50, Alex Bennée <alex.bennee@linaro.org> wrote:
>>
>>
>> Peter Maydell <peter.maydell@linaro.org> writes:
>>
>> > 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>
>> > ---
>> >  docs/system/arm/virt.rst |   1 +
>> >  hw/arm/sbsa-ref.c        |   1 +
>> >  hw/arm/virt.c            |   1 +
>> >  target/arm/tcg/cpu64.c   | 103 +++++++++++++++++++++++++++++++++++++++
>> >  4 files changed, 106 insertions(+)
>> >
>> > diff --git a/docs/system/arm/virt.rst b/docs/system/arm/virt.rst
>> > index e1697ac8f48..7c4c80180c6 100644
>> > --- a/docs/system/arm/virt.rst
>> > +++ b/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
>> > diff --git a/hw/arm/sbsa-ref.c b/hw/arm/sbsa-ref.c
>> > index bc89eb48062..4db287287e1 100644
>> > --- a/hw/arm/sbsa-ref.c
>> > +++ b/hw/arm/sbsa-ref.c
>> > @@ -154,6 +154,7 @@ 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"),
>> >  };
>> >
>> > diff --git a/hw/arm/virt.c b/hw/arm/virt.c
>> > index 8ad78b23c24..42253462735 100644
>> > --- a/hw/arm/virt.c
>> > +++ b/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"),
>> > diff --git a/target/arm/tcg/cpu64.c b/target/arm/tcg/cpu64.c
>> > index ea43cf3c1ee..370cc82f0ef 100644
>> > --- a/target/arm/tcg/cpu64.c
>> > +++ b/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 */
>>
>> Jonathan mentioned he was hacking about with MPAM so if there is a stub
>> implementation of the fields it would be nice to add them.
>
> I'm just following the existing A710 code here. There isn't
> a stub implementation of the fields, which is why there's
> just a TODO comment documenting the ID register value.
>
>> > +
>> > +    /* 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;
>>
>> Hmm reset_sctlr might need to be bigger because being used for sctlr_el3
>> is a 64 bit entity which has a number of fields:
>
> In theory, yes. In practice, only if we get to a point where we
> want to set some bit in the top 32 bits, which we don't yet.
>
>>
>>   - DSSBS,bit[44] to have some sort of impdef value
>>   - the others all look like architecturally UNKNOWN values
>>
>> Otherwise I think this is:
>>
>>   - 3 - RES1 29:28
>>   - 0 - RES0 + I assume LE EE bit
>>   - c - RES1 23, EIS 22 (architecturally UNKNOWN on reset)
>>   - 5 - RES1 18, 16
>>   - 0 - RES0 15:14, EnDB 13 (architecturally UNKNOWN on reset), I 12 RES0
>>   - 8 - EOS 11 (architecturally UNKNOWN on reset)
>>   - 3 - RES1 5:4
>>   - 8 - SA 3 (architecturally UNKNOWN on reset)
>>
>> It's a little confusing because the language describing these
>> architecturally unknown states refers to resetting to EL3 (I assume a
>> decent firmware would make sure everything is set correctly). Which
>> makes me wonder if reset_sctlr is really "sane values for a direct
>> kernel boot"?
>
> It's the hardware reset value, at least nominally speaking.
> We use the value for our SCTLR_EL1 if we aren't emulating EL2 or EL3,
> which means we diverge a little from the hardware which probably doesn't
> support an EL1-only config.
>
> To the extent that we need to set values here for kernel boot, we would
> do that in hw/arm/boot.c. But mostly we don't, because the kernel sets
> up the SCTLR register for the EL it is entered in.
>
> This used to be a bit better defined on older CPUs when previous
> versions of the architecture weren't so loose about values being
> UNKNOWN on reset. It's unfortunate that we don't have the documented
> value for whatever the IMPDEF reset value is for this CPU. In
> practice, because it's IMPDEF and UNKNOWN it doesn't matter too much --
> guest software will set it as needed. The value used here is "safe"
> because it's one we already use for other CPUs.

Fair enough:

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>

-- 
Alex Bennée
Virtualisation Tech Lead @ Linaro