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| author | Suzuki K Poulose <suzuki.poulose@arm.com> | 2016-04-18 10:28:35 +0100 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2016-04-20 12:22:42 +0100 |
| commit | a6dc3cd718ec2a19b8ca812087666899852af78f (patch) | |
| tree | f1ac05011fd06e703592a56076f4c7f245626af9 /arch/arm64/kernel/cpuinfo.c | |
| parent | c80aba803a9aa131f997f62a71ab453e456d08a8 (diff) | |
| download | talos-obmc-linux-a6dc3cd718ec2a19b8ca812087666899852af78f.tar.gz talos-obmc-linux-a6dc3cd718ec2a19b8ca812087666899852af78f.zip | |
arm64: cpufeature: Check availability of AArch32
On ARMv8 support for AArch32 state is optional. Hence it is
not safe to check the AArch32 ID registers for sanity, which
could lead to false warnings. This patch makes sure that the
AArch32 state is implemented before we keep track of the 32bit
ID registers.
As per ARM ARM (D.1.21.2 - Support for Exception Levels and
Execution States, DDI0487A.h), checking the support for AArch32
at EL0 is good enough to check the support for AArch32 (i.e,
AArch32 at EL1 => AArch32 at EL0, but not vice versa).
Tested-by: Yury Norov <ynorov@caviumnetworks.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'arch/arm64/kernel/cpuinfo.c')
| -rw-r--r-- | arch/arm64/kernel/cpuinfo.c | 37 |
1 files changed, 20 insertions, 17 deletions
diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c index 84c8684431c7..92189e2875f2 100644 --- a/arch/arm64/kernel/cpuinfo.c +++ b/arch/arm64/kernel/cpuinfo.c @@ -216,23 +216,26 @@ static void __cpuinfo_store_cpu(struct cpuinfo_arm64 *info) info->reg_id_aa64pfr0 = read_cpuid(ID_AA64PFR0_EL1); info->reg_id_aa64pfr1 = read_cpuid(ID_AA64PFR1_EL1); - info->reg_id_dfr0 = read_cpuid(ID_DFR0_EL1); - info->reg_id_isar0 = read_cpuid(ID_ISAR0_EL1); - info->reg_id_isar1 = read_cpuid(ID_ISAR1_EL1); - info->reg_id_isar2 = read_cpuid(ID_ISAR2_EL1); - info->reg_id_isar3 = read_cpuid(ID_ISAR3_EL1); - info->reg_id_isar4 = read_cpuid(ID_ISAR4_EL1); - info->reg_id_isar5 = read_cpuid(ID_ISAR5_EL1); - info->reg_id_mmfr0 = read_cpuid(ID_MMFR0_EL1); - info->reg_id_mmfr1 = read_cpuid(ID_MMFR1_EL1); - info->reg_id_mmfr2 = read_cpuid(ID_MMFR2_EL1); - info->reg_id_mmfr3 = read_cpuid(ID_MMFR3_EL1); - info->reg_id_pfr0 = read_cpuid(ID_PFR0_EL1); - info->reg_id_pfr1 = read_cpuid(ID_PFR1_EL1); - - info->reg_mvfr0 = read_cpuid(MVFR0_EL1); - info->reg_mvfr1 = read_cpuid(MVFR1_EL1); - info->reg_mvfr2 = read_cpuid(MVFR2_EL1); + /* Update the 32bit ID registers only if AArch32 is implemented */ + if (id_aa64pfr0_32bit_el0(info->reg_id_aa64pfr0)) { + info->reg_id_dfr0 = read_cpuid(ID_DFR0_EL1); + info->reg_id_isar0 = read_cpuid(ID_ISAR0_EL1); + info->reg_id_isar1 = read_cpuid(ID_ISAR1_EL1); + info->reg_id_isar2 = read_cpuid(ID_ISAR2_EL1); + info->reg_id_isar3 = read_cpuid(ID_ISAR3_EL1); + info->reg_id_isar4 = read_cpuid(ID_ISAR4_EL1); + info->reg_id_isar5 = read_cpuid(ID_ISAR5_EL1); + info->reg_id_mmfr0 = read_cpuid(ID_MMFR0_EL1); + info->reg_id_mmfr1 = read_cpuid(ID_MMFR1_EL1); + info->reg_id_mmfr2 = read_cpuid(ID_MMFR2_EL1); + info->reg_id_mmfr3 = read_cpuid(ID_MMFR3_EL1); + info->reg_id_pfr0 = read_cpuid(ID_PFR0_EL1); + info->reg_id_pfr1 = read_cpuid(ID_PFR1_EL1); + + info->reg_mvfr0 = read_cpuid(MVFR0_EL1); + info->reg_mvfr1 = read_cpuid(MVFR1_EL1); + info->reg_mvfr2 = read_cpuid(MVFR2_EL1); + } cpuinfo_detect_icache_policy(info); |
