[PATCH v2 16/21] arm64/hwcap: Define hwcaps for 2023 DPISA features

From: Mark Brown
Date: Tue Nov 14 2023 - 09:37:21 EST


The 2023 architecture extensions include a large number of floating point
features, most of which simply add new instructions. Add hwcaps so that
userspace can enumerate these features.

Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
Documentation/arch/arm64/elf_hwcaps.rst | 49 +++++++++++++++++++++++++++++++++
arch/arm64/include/asm/hwcap.h | 15 ++++++++++
arch/arm64/include/uapi/asm/hwcap.h | 15 ++++++++++
arch/arm64/kernel/cpufeature.c | 35 +++++++++++++++++++++++
arch/arm64/kernel/cpuinfo.c | 15 ++++++++++
5 files changed, 129 insertions(+)

diff --git a/Documentation/arch/arm64/elf_hwcaps.rst b/Documentation/arch/arm64/elf_hwcaps.rst
index ced7b335e2e0..448c1664879b 100644
--- a/Documentation/arch/arm64/elf_hwcaps.rst
+++ b/Documentation/arch/arm64/elf_hwcaps.rst
@@ -317,6 +317,55 @@ HWCAP2_LRCPC3
HWCAP2_LSE128
Functionality implied by ID_AA64ISAR0_EL1.Atomic == 0b0011.

+HWCAP2_FPMR
+ Functionality implied by ID_AA64PFR2_EL1.FMR == 0b0001.
+
+HWCAP2_LUT
+ Functionality implied by ID_AA64ISAR2_EL1.LUT == 0b0001.
+
+HWCAP2_FAMINMAX
+ Functionality implied by ID_AA64ISAR3_EL1.FAMINMAX == 0b0001.
+
+HWCAP2_F8CVT
+ Functionality implied by ID_AA64FPFR0_EL1.F8CVT == 0b1.
+
+HWCAP2_F8FMA
+ Functionality implied by ID_AA64FPFR0_EL1.F8FMA == 0b1.
+
+HWCAP2_F8DP4
+ Functionality implied by ID_AA64FPFR0_EL1.F8DP4 == 0b1.
+
+HWCAP2_F8DP2
+ Functionality implied by ID_AA64FPFR0_EL1.F8DP2 == 0b1.
+
+HWCAP2_F8E4M3
+ Functionality implied by ID_AA64FPFR0_EL1.F8E4M3 == 0b1.
+
+HWCAP2_F8E5M2
+ Functionality implied by ID_AA64FPFR0_EL1.F8E5M2 == 0b1.
+
+HWCAP2_SME_LUTV2
+ Functionality implied by ID_AA64SMFR0_EL1.LUTv2 == 0b1.
+
+HWCAP2_SME_F8F16
+ Functionality implied by ID_AA64SMFR0_EL1.F8F16 == 0b1.
+
+HWCAP2_SME_F8F32
+ Functionality implied by ID_AA64SMFR0_EL1.F8F32 == 0b1.
+
+HWCAP2_SME_SF8FMA
+ Functionality implied by ID_AA64SMFR0_EL1.SF8FMA == 0b1.
+
+HWCAP2_SME_SF8DP4
+ Functionality implied by ID_AA64SMFR0_EL1.SF8DP4 == 0b1.
+
+HWCAP2_SME_SF8DP2
+ Functionality implied by ID_AA64SMFR0_EL1.SF8DP2 == 0b1.
+
+HWCAP2_SME_SF8DP4
+ Functionality implied by ID_AA64SMFR0_EL1.SF8DP4 == 0b1.
+
+
4. Unused AT_HWCAP bits
-----------------------

diff --git a/arch/arm64/include/asm/hwcap.h b/arch/arm64/include/asm/hwcap.h
index cd71e09ea14d..4edd3b61df11 100644
--- a/arch/arm64/include/asm/hwcap.h
+++ b/arch/arm64/include/asm/hwcap.h
@@ -142,6 +142,21 @@
#define KERNEL_HWCAP_SVE_B16B16 __khwcap2_feature(SVE_B16B16)
#define KERNEL_HWCAP_LRCPC3 __khwcap2_feature(LRCPC3)
#define KERNEL_HWCAP_LSE128 __khwcap2_feature(LSE128)
+#define KERNEL_HWCAP_FPMR __khwcap2_feature(FPMR)
+#define KERNEL_HWCAP_LUT __khwcap2_feature(LUT)
+#define KERNEL_HWCAP_FAMINMAX __khwcap2_feature(FAMINMAX)
+#define KERNEL_HWCAP_F8CVT __khwcap2_feature(F8CVT)
+#define KERNEL_HWCAP_F8FMA __khwcap2_feature(F8FMA)
+#define KERNEL_HWCAP_F8DP4 __khwcap2_feature(F8DP4)
+#define KERNEL_HWCAP_F8DP2 __khwcap2_feature(F8DP2)
+#define KERNEL_HWCAP_F8E4M3 __khwcap2_feature(F8E4M3)
+#define KERNEL_HWCAP_F8E5M2 __khwcap2_feature(F8E5M2)
+#define KERNEL_HWCAP_SME_LUTV2 __khwcap2_feature(SME_LUTV2)
+#define KERNEL_HWCAP_SME_F8F16 __khwcap2_feature(SME_F8F16)
+#define KERNEL_HWCAP_SME_F8F32 __khwcap2_feature(SME_F8F32)
+#define KERNEL_HWCAP_SME_SF8FMA __khwcap2_feature(SME_SF8FMA)
+#define KERNEL_HWCAP_SME_SF8DP4 __khwcap2_feature(SME_SF8DP4)
+#define KERNEL_HWCAP_SME_SF8DP2 __khwcap2_feature(SME_SF8DP2)

/*
* This yields a mask that user programs can use to figure out what
diff --git a/arch/arm64/include/uapi/asm/hwcap.h b/arch/arm64/include/uapi/asm/hwcap.h
index 5023599fa278..285610e626f5 100644
--- a/arch/arm64/include/uapi/asm/hwcap.h
+++ b/arch/arm64/include/uapi/asm/hwcap.h
@@ -107,5 +107,20 @@
#define HWCAP2_SVE_B16B16 (1UL << 45)
#define HWCAP2_LRCPC3 (1UL << 46)
#define HWCAP2_LSE128 (1UL << 47)
+#define HWCAP2_FPMR (1UL << 48)
+#define HWCAP2_LUT (1UL << 49)
+#define HWCAP2_FAMINMAX (1UL << 50)
+#define HWCAP2_F8CVT (1UL << 51)
+#define HWCAP2_F8FMA (1UL << 52)
+#define HWCAP2_F8DP4 (1UL << 53)
+#define HWCAP2_F8DP2 (1UL << 54)
+#define HWCAP2_F8E4M3 (1UL << 55)
+#define HWCAP2_F8E5M2 (1UL << 56)
+#define HWCAP2_SME_LUTV2 (1UL << 57)
+#define HWCAP2_SME_F8F16 (1UL << 58)
+#define HWCAP2_SME_F8F32 (1UL << 59)
+#define HWCAP2_SME_SF8FMA (1UL << 60)
+#define HWCAP2_SME_SF8DP4 (1UL << 61)
+#define HWCAP2_SME_SF8DP2 (1UL << 62)

#endif /* _UAPI__ASM_HWCAP_H */
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index ea0b680792de..33e301b6e31e 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -220,6 +220,7 @@ static const struct arm64_ftr_bits ftr_id_aa64isar1[] = {
};

static const struct arm64_ftr_bits ftr_id_aa64isar2[] = {
+ ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_EL1_LUT_SHIFT, 4, 0),
ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_EL1_CSSC_SHIFT, 4, 0),
ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_EL1_RPRFM_SHIFT, 4, 0),
ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_EL1_CLRBHB_SHIFT, 4, 0),
@@ -235,6 +236,7 @@ static const struct arm64_ftr_bits ftr_id_aa64isar2[] = {
};

static const struct arm64_ftr_bits ftr_id_aa64isar3[] = {
+ ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64ISAR3_EL1_FAMINMAX_SHIFT, 4, 0),
ARM64_FTR_END,
};

@@ -303,6 +305,8 @@ static const struct arm64_ftr_bits ftr_id_aa64zfr0[] = {
static const struct arm64_ftr_bits ftr_id_aa64smfr0[] = {
ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_FA64_SHIFT, 1, 0),
+ ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
+ FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_LUTv2_SHIFT, 1, 0),
ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_SMEver_SHIFT, 4, 0),
ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
@@ -315,6 +319,10 @@ static const struct arm64_ftr_bits ftr_id_aa64smfr0[] = {
FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_B16B16_SHIFT, 1, 0),
ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_F16F16_SHIFT, 1, 0),
+ ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
+ FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_F8F16_SHIFT, 1, 0),
+ ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
+ FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_F8F32_SHIFT, 1, 0),
ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_I8I32_SHIFT, 4, 0),
ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
@@ -325,10 +333,22 @@ static const struct arm64_ftr_bits ftr_id_aa64smfr0[] = {
FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_BI32I32_SHIFT, 1, 0),
ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_F32F32_SHIFT, 1, 0),
+ ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
+ FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_SF8FMA_SHIFT, 1, 0),
+ ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
+ FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_SF8DP4_SHIFT, 1, 0),
+ ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME),
+ FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_SF8DP2_SHIFT, 1, 0),
ARM64_FTR_END,
};

static const struct arm64_ftr_bits ftr_id_aa64fpfr0[] = {
+ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, ID_AA64FPFR0_EL1_F8CVT_SHIFT, 1, 0),
+ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, ID_AA64FPFR0_EL1_F8FMA_SHIFT, 1, 0),
+ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, ID_AA64FPFR0_EL1_F8DP4_SHIFT, 1, 0),
+ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, ID_AA64FPFR0_EL1_F8DP2_SHIFT, 1, 0),
+ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, ID_AA64FPFR0_EL1_F8E4M3_SHIFT, 1, 0),
+ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, ID_AA64FPFR0_EL1_F8E5M2_SHIFT, 1, 0),
ARM64_FTR_END,
};

@@ -2851,6 +2871,7 @@ static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
HWCAP_CAP(ID_AA64PFR0_EL1, AdvSIMD, IMP, CAP_HWCAP, KERNEL_HWCAP_ASIMD),
HWCAP_CAP(ID_AA64PFR0_EL1, AdvSIMD, FP16, CAP_HWCAP, KERNEL_HWCAP_ASIMDHP),
HWCAP_CAP(ID_AA64PFR0_EL1, DIT, IMP, CAP_HWCAP, KERNEL_HWCAP_DIT),
+ HWCAP_CAP(ID_AA64PFR2_EL1, FPMR, IMP, CAP_HWCAP, KERNEL_HWCAP_FPMR),
HWCAP_CAP(ID_AA64ISAR1_EL1, DPB, IMP, CAP_HWCAP, KERNEL_HWCAP_DCPOP),
HWCAP_CAP(ID_AA64ISAR1_EL1, DPB, DPB2, CAP_HWCAP, KERNEL_HWCAP_DCPODP),
HWCAP_CAP(ID_AA64ISAR1_EL1, JSCVT, IMP, CAP_HWCAP, KERNEL_HWCAP_JSCVT),
@@ -2864,6 +2885,8 @@ static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
HWCAP_CAP(ID_AA64ISAR1_EL1, BF16, EBF16, CAP_HWCAP, KERNEL_HWCAP_EBF16),
HWCAP_CAP(ID_AA64ISAR1_EL1, DGH, IMP, CAP_HWCAP, KERNEL_HWCAP_DGH),
HWCAP_CAP(ID_AA64ISAR1_EL1, I8MM, IMP, CAP_HWCAP, KERNEL_HWCAP_I8MM),
+ HWCAP_CAP(ID_AA64ISAR2_EL1, LUT, IMP, CAP_HWCAP, KERNEL_HWCAP_LUT),
+ HWCAP_CAP(ID_AA64ISAR3_EL1, FAMINMAX, IMP, CAP_HWCAP, KERNEL_HWCAP_FAMINMAX),
HWCAP_CAP(ID_AA64MMFR2_EL1, AT, IMP, CAP_HWCAP, KERNEL_HWCAP_USCAT),
#ifdef CONFIG_ARM64_SVE
HWCAP_CAP(ID_AA64PFR0_EL1, SVE, IMP, CAP_HWCAP, KERNEL_HWCAP_SVE),
@@ -2904,6 +2927,7 @@ static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
#ifdef CONFIG_ARM64_SME
HWCAP_CAP(ID_AA64PFR1_EL1, SME, IMP, CAP_HWCAP, KERNEL_HWCAP_SME),
HWCAP_CAP(ID_AA64SMFR0_EL1, FA64, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_FA64),
+ HWCAP_CAP(ID_AA64SMFR0_EL1, LUTv2, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_LUTV2),
HWCAP_CAP(ID_AA64SMFR0_EL1, SMEver, SME2p1, CAP_HWCAP, KERNEL_HWCAP_SME2P1),
HWCAP_CAP(ID_AA64SMFR0_EL1, SMEver, SME2, CAP_HWCAP, KERNEL_HWCAP_SME2),
HWCAP_CAP(ID_AA64SMFR0_EL1, I16I64, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_I16I64),
@@ -2911,12 +2935,23 @@ static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
HWCAP_CAP(ID_AA64SMFR0_EL1, I16I32, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_I16I32),
HWCAP_CAP(ID_AA64SMFR0_EL1, B16B16, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_B16B16),
HWCAP_CAP(ID_AA64SMFR0_EL1, F16F16, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_F16F16),
+ HWCAP_CAP(ID_AA64SMFR0_EL1, F8F16, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_F8F16),
+ HWCAP_CAP(ID_AA64SMFR0_EL1, F8F32, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_F8F32),
HWCAP_CAP(ID_AA64SMFR0_EL1, I8I32, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_I8I32),
HWCAP_CAP(ID_AA64SMFR0_EL1, F16F32, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_F16F32),
HWCAP_CAP(ID_AA64SMFR0_EL1, B16F32, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_B16F32),
HWCAP_CAP(ID_AA64SMFR0_EL1, BI32I32, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_BI32I32),
HWCAP_CAP(ID_AA64SMFR0_EL1, F32F32, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_F32F32),
+ HWCAP_CAP(ID_AA64SMFR0_EL1, SF8FMA, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_SF8FMA),
+ HWCAP_CAP(ID_AA64SMFR0_EL1, SF8DP4, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_SF8DP4),
+ HWCAP_CAP(ID_AA64SMFR0_EL1, SF8DP2, IMP, CAP_HWCAP, KERNEL_HWCAP_SME_SF8DP2),
#endif /* CONFIG_ARM64_SME */
+ HWCAP_CAP(ID_AA64FPFR0_EL1, F8CVT, IMP, CAP_HWCAP, KERNEL_HWCAP_F8CVT),
+ HWCAP_CAP(ID_AA64FPFR0_EL1, F8FMA, IMP, CAP_HWCAP, KERNEL_HWCAP_F8FMA),
+ HWCAP_CAP(ID_AA64FPFR0_EL1, F8DP4, IMP, CAP_HWCAP, KERNEL_HWCAP_F8DP4),
+ HWCAP_CAP(ID_AA64FPFR0_EL1, F8DP2, IMP, CAP_HWCAP, KERNEL_HWCAP_F8DP2),
+ HWCAP_CAP(ID_AA64FPFR0_EL1, F8E4M3, IMP, CAP_HWCAP, KERNEL_HWCAP_F8E4M3),
+ HWCAP_CAP(ID_AA64FPFR0_EL1, F8E5M2, IMP, CAP_HWCAP, KERNEL_HWCAP_F8E5M2),
{},
};

diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c
index 8322e968fd0d..29155107d35d 100644
--- a/arch/arm64/kernel/cpuinfo.c
+++ b/arch/arm64/kernel/cpuinfo.c
@@ -130,6 +130,21 @@ static const char *const hwcap_str[] = {
[KERNEL_HWCAP_SVE_B16B16] = "sveb16b16",
[KERNEL_HWCAP_LRCPC3] = "lrcpc3",
[KERNEL_HWCAP_LSE128] = "lse128",
+ [KERNEL_HWCAP_FPMR] = "fpmr",
+ [KERNEL_HWCAP_LUT] = "lut",
+ [KERNEL_HWCAP_FAMINMAX] = "faminmax",
+ [KERNEL_HWCAP_F8CVT] = "f8cvt",
+ [KERNEL_HWCAP_F8FMA] = "f8fma",
+ [KERNEL_HWCAP_F8DP4] = "f8dp4",
+ [KERNEL_HWCAP_F8DP2] = "f8dp2",
+ [KERNEL_HWCAP_F8E4M3] = "f8e4m3",
+ [KERNEL_HWCAP_F8E5M2] = "f8e5m2",
+ [KERNEL_HWCAP_SME_LUTV2] = "smelutv2",
+ [KERNEL_HWCAP_SME_F8F16] = "smef8f16",
+ [KERNEL_HWCAP_SME_F8F32] = "smef8f32",
+ [KERNEL_HWCAP_SME_SF8FMA] = "smesf8fma",
+ [KERNEL_HWCAP_SME_SF8DP4] = "smesf8dp4",
+ [KERNEL_HWCAP_SME_SF8DP2] = "smesf8dp2",
};

#ifdef CONFIG_COMPAT

--
2.30.2