[PATCH 2/3] arm64: v8.3: Support for complex number instructions

From: Suzuki K Poulose
Date: Tue Mar 14 2017 - 14:14:17 EST


ARM v8.3 adds support for new instructions to aid floating-point
multiplication and addition of complex numbers. Expose the support
via HWCAP and MRS emulation

Signed-off-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
---
Documentation/arm64/cpu-feature-registers.txt | 2 ++
arch/arm64/include/asm/sysreg.h | 1 +
arch/arm64/include/uapi/asm/hwcap.h | 1 +
arch/arm64/kernel/cpufeature.c | 2 ++
arch/arm64/kernel/cpuinfo.c | 1 +
5 files changed, 7 insertions(+)

diff --git a/Documentation/arm64/cpu-feature-registers.txt b/Documentation/arm64/cpu-feature-registers.txt
index 5b279dc..0ce0a40 100644
--- a/Documentation/arm64/cpu-feature-registers.txt
+++ b/Documentation/arm64/cpu-feature-registers.txt
@@ -174,6 +174,8 @@ infrastructure:
x--------------------------------------------------x
| Name | bits | visible |
|--------------------------------------------------|
+ | FCMA | [19-16] | y |
+ |--------------------------------------------------|
| JSCVT | [15-12] | y |
x--------------------------------------------------x

diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index cbb3143..69af995 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -157,6 +157,7 @@
#define ID_AA64ISAR0_AES_SHIFT 4

/* id_aa64isar1 */
+#define ID_AA64ISAR1_FCMA_SHIFT 16
#define ID_AA64ISAR1_JSCVT_SHIFT 12

/* id_aa64pfr0 */
diff --git a/arch/arm64/include/uapi/asm/hwcap.h b/arch/arm64/include/uapi/asm/hwcap.h
index 391a876..85841a4 100644
--- a/arch/arm64/include/uapi/asm/hwcap.h
+++ b/arch/arm64/include/uapi/asm/hwcap.h
@@ -33,5 +33,6 @@
#define HWCAP_CPUID (1 << 11)
#define HWCAP_ASIMDRDM (1 << 12)
#define HWCAP_JSCVT (1 << 13)
+#define HWCAP_FCMA (1 << 14)

#endif /* _UAPI__ASM_HWCAP_H */
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index af88910..a5ff8ae 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -98,6 +98,7 @@ static const struct arm64_ftr_bits ftr_id_aa64isar0[] = {
};

static const struct arm64_ftr_bits ftr_id_aa64isar1[] = {
+ ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, ID_AA64ISAR1_FCMA_SHIFT, 4, 0),
ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_EXACT, ID_AA64ISAR1_JSCVT_SHIFT, 4, 0),
ARM64_FTR_END,
};
@@ -894,6 +895,7 @@ static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = {
HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 0, CAP_HWCAP, HWCAP_ASIMD),
HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, HWCAP_ASIMDHP),
HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_JSCVT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_JSCVT),
+ HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FCMA_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, HWCAP_FCMA),
{},
};

diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c
index 95cfd33..e6afed8 100644
--- a/arch/arm64/kernel/cpuinfo.c
+++ b/arch/arm64/kernel/cpuinfo.c
@@ -66,6 +66,7 @@ static const char *const hwcap_str[] = {
"cpuid",
"asimdrdm",
"jscvt",
+ "fcma",
NULL
};

--
2.7.4