[PATCH 1/6] arm64/cpufeature: Introduce ID_PFR2 CPU register

From: Anshuman Khandual
Date: Tue Jan 28 2020 - 07:39:37 EST


This adds basic building blocks required for ID_PFR2 CPU register which
provides information about the AArch32 programmers model which must be
interpreted along with ID_PFR0 and ID_PFR1 CPU registers.

Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Marc Zyngier <maz@xxxxxxxxxx>
Cc: James Morse <james.morse@xxxxxxx>
Cc: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: kvmarm@xxxxxxxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>
---
arch/arm64/include/asm/cpu.h | 1 +
arch/arm64/include/asm/sysreg.h | 4 ++++
arch/arm64/kernel/cpufeature.c | 11 +++++++++++
arch/arm64/kernel/cpuinfo.c | 1 +
arch/arm64/kvm/sys_regs.c | 2 +-
5 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/include/asm/cpu.h b/arch/arm64/include/asm/cpu.h
index b4a40535a3d8..464e828a994d 100644
--- a/arch/arm64/include/asm/cpu.h
+++ b/arch/arm64/include/asm/cpu.h
@@ -46,6 +46,7 @@ struct cpuinfo_arm64 {
u32 reg_id_mmfr3;
u32 reg_id_pfr0;
u32 reg_id_pfr1;
+ u32 reg_id_pfr2;

u32 reg_mvfr0;
u32 reg_mvfr1;
diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index b91570ff9db1..054aab7ebf1b 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -151,6 +151,7 @@
#define SYS_MVFR0_EL1 sys_reg(3, 0, 0, 3, 0)
#define SYS_MVFR1_EL1 sys_reg(3, 0, 0, 3, 1)
#define SYS_MVFR2_EL1 sys_reg(3, 0, 0, 3, 2)
+#define SYS_ID_PFR2_EL1 sys_reg(3, 0, 0, 3, 4)

#define SYS_ID_AA64PFR0_EL1 sys_reg(3, 0, 0, 4, 0)
#define SYS_ID_AA64PFR1_EL1 sys_reg(3, 0, 0, 4, 1)
@@ -717,6 +718,9 @@
#define ID_ISAR6_DP_SHIFT 4
#define ID_ISAR6_JSCVT_SHIFT 0

+#define ID_PFR2_SSBS_SHIFT 4
+#define ID_PFR2_CSV3_SHIFT 0
+
#define MVFR0_FPROUND_SHIFT 28
#define MVFR0_FPSHVEC_SHIFT 24
#define MVFR0_FPSQRT_SHIFT 20
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 0b6715625cf6..c1e837fc8f97 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -348,6 +348,12 @@ static const struct arm64_ftr_bits ftr_id_pfr0[] = {
ARM64_FTR_END,
};

+static const struct arm64_ftr_bits ftr_id_pfr2[] = {
+ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR2_SSBS_SHIFT, 4, 0),
+ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR2_CSV3_SHIFT, 4, 0),
+ ARM64_FTR_END,
+};
+
static const struct arm64_ftr_bits ftr_id_dfr0[] = {
ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 28, 4, 0),
S_ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 24, 4, 0xf), /* PerfMon */
@@ -429,6 +435,7 @@ static const struct __ftr_reg_entry {
ARM64_FTR_REG(SYS_MVFR0_EL1, ftr_generic_32bits),
ARM64_FTR_REG(SYS_MVFR1_EL1, ftr_generic_32bits),
ARM64_FTR_REG(SYS_MVFR2_EL1, ftr_mvfr2),
+ ARM64_FTR_REG(SYS_ID_PFR2_EL1, ftr_id_pfr2),

/* Op1 = 0, CRn = 0, CRm = 4 */
ARM64_FTR_REG(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0),
@@ -635,6 +642,7 @@ void __init init_cpu_features(struct cpuinfo_arm64 *info)
init_cpu_ftr_reg(SYS_ID_MMFR3_EL1, info->reg_id_mmfr3);
init_cpu_ftr_reg(SYS_ID_PFR0_EL1, info->reg_id_pfr0);
init_cpu_ftr_reg(SYS_ID_PFR1_EL1, info->reg_id_pfr1);
+ init_cpu_ftr_reg(SYS_ID_PFR2_EL1, info->reg_id_pfr2);
init_cpu_ftr_reg(SYS_MVFR0_EL1, info->reg_mvfr0);
init_cpu_ftr_reg(SYS_MVFR1_EL1, info->reg_mvfr1);
init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2);
@@ -802,6 +810,8 @@ void update_cpu_features(int cpu,
info->reg_id_pfr0, boot->reg_id_pfr0);
taint |= check_update_ftr_reg(SYS_ID_PFR1_EL1, cpu,
info->reg_id_pfr1, boot->reg_id_pfr1);
+ taint |= check_update_ftr_reg(SYS_ID_PFR2_EL1, cpu,
+ info->reg_id_pfr2, boot->reg_id_pfr2);
taint |= check_update_ftr_reg(SYS_MVFR0_EL1, cpu,
info->reg_mvfr0, boot->reg_mvfr0);
taint |= check_update_ftr_reg(SYS_MVFR1_EL1, cpu,
@@ -851,6 +861,7 @@ static u64 __read_sysreg_by_encoding(u32 sys_id)
switch (sys_id) {
read_sysreg_case(SYS_ID_PFR0_EL1);
read_sysreg_case(SYS_ID_PFR1_EL1);
+ read_sysreg_case(SYS_ID_PFR2_EL1);
read_sysreg_case(SYS_ID_DFR0_EL1);
read_sysreg_case(SYS_ID_MMFR0_EL1);
read_sysreg_case(SYS_ID_MMFR1_EL1);
diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c
index 86136075ae41..cb79b083f97f 100644
--- a/arch/arm64/kernel/cpuinfo.c
+++ b/arch/arm64/kernel/cpuinfo.c
@@ -375,6 +375,7 @@ static void __cpuinfo_store_cpu(struct cpuinfo_arm64 *info)
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_id_pfr2 = read_cpuid(ID_PFR2_EL1);

info->reg_mvfr0 = read_cpuid(MVFR0_EL1);
info->reg_mvfr1 = read_cpuid(MVFR1_EL1);
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c
index 3e909b117f0c..e266219a35ff 100644
--- a/arch/arm64/kvm/sys_regs.c
+++ b/arch/arm64/kvm/sys_regs.c
@@ -1431,7 +1431,7 @@ static const struct sys_reg_desc sys_reg_descs[] = {
ID_SANITISED(MVFR1_EL1),
ID_SANITISED(MVFR2_EL1),
ID_UNALLOCATED(3,3),
- ID_UNALLOCATED(3,4),
+ ID_SANITISED(ID_PFR2_EL1),
ID_UNALLOCATED(3,5),
ID_UNALLOCATED(3,6),
ID_UNALLOCATED(3,7),
--
2.20.1