From 35382a3646404891aba092013b855c3db4b8b487 Mon Sep 17 00:00:00 2001 From: Yicong Yang Date: Sat, 29 Mar 2025 11:44:07 +0800 Subject: [PATCH 1/3] arm64/cpufeature: Add missing id_aa64mmfr4 feature reg update Add missing id_aa64mmfr4 feature register check and update in update_cpu_features(). Update the taint status as well. Signed-off-by: Yicong Yang Link: https://lore.kernel.org/r/20250329034409.21354-2-yangyicong@huawei.com Signed-off-by: Will Deacon --- arch/arm64/kernel/cpufeature.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 9c4d6d552b25..75ef319c1ef8 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -1403,6 +1403,8 @@ void update_cpu_features(int cpu, info->reg_id_aa64mmfr2, boot->reg_id_aa64mmfr2); taint |= check_update_ftr_reg(SYS_ID_AA64MMFR3_EL1, cpu, info->reg_id_aa64mmfr3, boot->reg_id_aa64mmfr3); + taint |= check_update_ftr_reg(SYS_ID_AA64MMFR4_EL1, cpu, + info->reg_id_aa64mmfr4, boot->reg_id_aa64mmfr4); taint |= check_update_ftr_reg(SYS_ID_AA64PFR0_EL1, cpu, info->reg_id_aa64pfr0, boot->reg_id_aa64pfr0); From 17efc1acee6229e8964d248e2a21def519e04c14 Mon Sep 17 00:00:00 2001 From: Oliver Upton Date: Thu, 3 Apr 2025 16:16:26 -0700 Subject: [PATCH 2/3] arm64: Expose AIDR_EL1 via sysfs The KVM PV ABI recently added a feature that allows the VM to discover the set of physical CPU implementations, identified by a tuple of {MIDR_EL1, REVIDR_EL1, AIDR_EL1}. Unlike other KVM PV features, the expectation is that the VMM implements the hypercall instead of KVM as it has the authoritative view of where the VM gets scheduled. To do this the VMM needs to know the values of these registers on any CPU in the system. While MIDR_EL1 and REVIDR_EL1 are already exposed, AIDR_EL1 is not. Provide it in sysfs along with the other identification registers. Signed-off-by: Oliver Upton Reviewed-by: Cornelia Huck Reviewed-by: Anshuman Khandual Link: https://lore.kernel.org/r/20250403231626.3181116-1-oliver.upton@linux.dev Signed-off-by: Will Deacon --- Documentation/ABI/testing/sysfs-devices-system-cpu | 1 + Documentation/arch/arm64/cpu-feature-registers.rst | 13 +++++++------ arch/arm64/include/asm/cpu.h | 1 + arch/arm64/kernel/cpuinfo.c | 3 +++ 4 files changed, 12 insertions(+), 6 deletions(-) diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu index 206079d3bd5b..9bbf4c27c237 100644 --- a/Documentation/ABI/testing/sysfs-devices-system-cpu +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu @@ -485,6 +485,7 @@ What: /sys/devices/system/cpu/cpuX/regs/ /sys/devices/system/cpu/cpuX/regs/identification/ /sys/devices/system/cpu/cpuX/regs/identification/midr_el1 /sys/devices/system/cpu/cpuX/regs/identification/revidr_el1 + /sys/devices/system/cpu/cpuX/regs/identification/aidr_el1 /sys/devices/system/cpu/cpuX/regs/identification/smidr_el1 Date: June 2016 Contact: Linux ARM Kernel Mailing list diff --git a/Documentation/arch/arm64/cpu-feature-registers.rst b/Documentation/arch/arm64/cpu-feature-registers.rst index 253e9743de2f..add66afc7b03 100644 --- a/Documentation/arch/arm64/cpu-feature-registers.rst +++ b/Documentation/arch/arm64/cpu-feature-registers.rst @@ -72,14 +72,15 @@ there are some issues with their usage. process could be migrated to another CPU by the time it uses the register value, unless the CPU affinity is set. Hence, there is no guarantee that the value reflects the processor that it is - currently executing on. The REVIDR is not exposed due to this - constraint, as REVIDR makes sense only in conjunction with the - MIDR. Alternately, MIDR_EL1 and REVIDR_EL1 are exposed via sysfs - at:: + currently executing on. REVIDR and AIDR are not exposed due to this + constraint, as these registers only make sense in conjunction with + the MIDR. Alternately, MIDR_EL1, REVIDR_EL1, and AIDR_EL1 are exposed + via sysfs at:: /sys/devices/system/cpu/cpu$ID/regs/identification/ - \- midr - \- revidr + \- midr_el1 + \- revidr_el1 + \- aidr_el1 3. Implementation -------------------- diff --git a/arch/arm64/include/asm/cpu.h b/arch/arm64/include/asm/cpu.h index 81e4157f92b7..71493b760b83 100644 --- a/arch/arm64/include/asm/cpu.h +++ b/arch/arm64/include/asm/cpu.h @@ -44,6 +44,7 @@ struct cpuinfo_arm64 { u64 reg_dczid; u64 reg_midr; u64 reg_revidr; + u64 reg_aidr; u64 reg_gmid; u64 reg_smidr; u64 reg_mpamidr; diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c index 285d7d538342..621218d2a991 100644 --- a/arch/arm64/kernel/cpuinfo.c +++ b/arch/arm64/kernel/cpuinfo.c @@ -328,11 +328,13 @@ static const struct kobj_type cpuregs_kobj_type = { CPUREGS_ATTR_RO(midr_el1, midr); CPUREGS_ATTR_RO(revidr_el1, revidr); +CPUREGS_ATTR_RO(aidr_el1, aidr); CPUREGS_ATTR_RO(smidr_el1, smidr); static struct attribute *cpuregs_id_attrs[] = { &cpuregs_attr_midr_el1.attr, &cpuregs_attr_revidr_el1.attr, + &cpuregs_attr_aidr_el1.attr, NULL }; @@ -469,6 +471,7 @@ static void __cpuinfo_store_cpu(struct cpuinfo_arm64 *info) info->reg_dczid = read_cpuid(DCZID_EL0); info->reg_midr = read_cpuid_id(); info->reg_revidr = read_cpuid(REVIDR_EL1); + info->reg_aidr = read_cpuid(AIDR_EL1); info->reg_id_aa64dfr0 = read_cpuid(ID_AA64DFR0_EL1); info->reg_id_aa64dfr1 = read_cpuid(ID_AA64DFR1_EL1); From 226ff35039d05826b738160eff05844c0fa5c2a0 Mon Sep 17 00:00:00 2001 From: Yicong Yang Date: Fri, 25 Apr 2025 11:38:43 +0800 Subject: [PATCH 3/3] arm64: cputype: Add cputype definition for HIP12 Add MIDR encoding for HiSilicon HIP12 which is used on HiSilicon HIP12 SoCs. Signed-off-by: Yicong Yang Link: https://lore.kernel.org/r/20250425033845.57671-2-yangyicong@huawei.com Signed-off-by: Will Deacon --- arch/arm64/include/asm/cputype.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/arm64/include/asm/cputype.h b/arch/arm64/include/asm/cputype.h index d1cc0571798b..36c5bbfbb6e9 100644 --- a/arch/arm64/include/asm/cputype.h +++ b/arch/arm64/include/asm/cputype.h @@ -133,6 +133,7 @@ #define HISI_CPU_PART_TSV110 0xD01 #define HISI_CPU_PART_HIP09 0xD02 +#define HISI_CPU_PART_HIP12 0xD06 #define APPLE_CPU_PART_M1_ICESTORM 0x022 #define APPLE_CPU_PART_M1_FIRESTORM 0x023 @@ -220,6 +221,7 @@ #define MIDR_FUJITSU_A64FX MIDR_CPU_MODEL(ARM_CPU_IMP_FUJITSU, FUJITSU_CPU_PART_A64FX) #define MIDR_HISI_TSV110 MIDR_CPU_MODEL(ARM_CPU_IMP_HISI, HISI_CPU_PART_TSV110) #define MIDR_HISI_HIP09 MIDR_CPU_MODEL(ARM_CPU_IMP_HISI, HISI_CPU_PART_HIP09) +#define MIDR_HISI_HIP12 MIDR_CPU_MODEL(ARM_CPU_IMP_HISI, HISI_CPU_PART_HIP12) #define MIDR_APPLE_M1_ICESTORM MIDR_CPU_MODEL(ARM_CPU_IMP_APPLE, APPLE_CPU_PART_M1_ICESTORM) #define MIDR_APPLE_M1_FIRESTORM MIDR_CPU_MODEL(ARM_CPU_IMP_APPLE, APPLE_CPU_PART_M1_FIRESTORM) #define MIDR_APPLE_M1_ICESTORM_PRO MIDR_CPU_MODEL(ARM_CPU_IMP_APPLE, APPLE_CPU_PART_M1_ICESTORM_PRO)