[PATCH 4/6] arm64: Expose DC CVADP to userspace
From: Andrew Murray <hidden>
Date: 2019-02-06 13:37:09
Subsystem:
arm64 port (aarch64 architecture), documentation, the rest · Maintainers:
Catalin Marinas, Will Deacon, Jonathan Corbet, Linus Torvalds
ARMv8.5 builds upon the ARMv8.2 DC CVAP instruction by introducing a DC CVADP instruction which cleans the data cache to the point of deep persistence. Let's expose this support via the arm64 ELF hwcaps. Signed-off-by: Andrew Murray <redacted> --- Documentation/arm64/elf_hwcaps.txt | 4 ++++ arch/arm64/include/asm/hwcap.h | 1 + arch/arm64/include/uapi/asm/hwcap.h | 5 +++++ arch/arm64/kernel/cpufeature.c | 1 + arch/arm64/kernel/cpuinfo.c | 1 + 5 files changed, 12 insertions(+)
diff --git a/Documentation/arm64/elf_hwcaps.txt b/Documentation/arm64/elf_hwcaps.txt
index 13d6691..7db6e13 100644
--- a/Documentation/arm64/elf_hwcaps.txt
+++ b/Documentation/arm64/elf_hwcaps.txt@@ -135,6 +135,10 @@ HWCAP_DCPOP Functionality implied by ID_AA64ISAR1_EL1.DPB == 0b0001. +HWCAP_DCPODP + + Functionality implied by ID_AA64ISAR1_EL1.DPB == 0b0010. + HWCAP_SHA3 Functionality implied by ID_AA64ISAR0_EL1.SHA3 == 0b0001.
diff --git a/arch/arm64/include/asm/hwcap.h b/arch/arm64/include/asm/hwcap.h
index ced87ad..8696db9 100644
--- a/arch/arm64/include/asm/hwcap.h
+++ b/arch/arm64/include/asm/hwcap.h@@ -75,6 +75,7 @@ #define KERNEL_HWCAP_SB ilog2(HWCAP_SB) #define KERNEL_HWCAP_PACA ilog2(HWCAP_PACA) #define KERNEL_HWCAP_PACG ilog2(HWCAP_PACG) +#define KERNEL_HWCAP_DCPODP (ilog2(HWCAP2_DCPODP) + 32) #ifndef __ASSEMBLY__ /*
diff --git a/arch/arm64/include/uapi/asm/hwcap.h b/arch/arm64/include/uapi/asm/hwcap.h
index 453b45a..d64af39 100644
--- a/arch/arm64/include/uapi/asm/hwcap.h
+++ b/arch/arm64/include/uapi/asm/hwcap.h@@ -53,4 +53,9 @@ #define HWCAP_PACA (1 << 30) #define HWCAP_PACG (1UL << 31) +/* + * HWCAP2 flags - for AT_HWCAP2 + */ +#define HWCAP2_DCPODP (1 << 0) + #endif /* _UAPI__ASM_HWCAP_H */
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 5b9620d..4c0c5b9 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c@@ -1556,6 +1556,7 @@ static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = { HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_ASIMD_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ASIMDHP), HWCAP_CAP(SYS_ID_AA64PFR0_EL1, ID_AA64PFR0_DIT_SHIFT, FTR_SIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DIT), HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_DCPOP), + HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_DPB_SHIFT, FTR_UNSIGNED, 2, CAP_HWCAP, KERNEL_HWCAP_DCPODP), HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_JSCVT_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_JSCVT), HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_FCMA_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_FCMA), HWCAP_CAP(SYS_ID_AA64ISAR1_EL1, ID_AA64ISAR1_LRCPC_SHIFT, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_LRCPC),
diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c
index 810db95..093ca53 100644
--- a/arch/arm64/kernel/cpuinfo.c
+++ b/arch/arm64/kernel/cpuinfo.c@@ -85,6 +85,7 @@ static const char *const hwcap_str[] = { "sb", "paca", "pacg", + "dcpodp", NULL };
--
2.7.4
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