Commit 671db581 authored by Andrew Murray's avatar Andrew Murray Committed by Will Deacon
Browse files

arm64: Expose DC CVADP to userspace 



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: default avatarAndrew Murray <andrew.murray@arm.com>
Reviewed-by: default avatarDave Martin <Dave.Martin@arm.com>
Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
parent d16ed410

Documentation/arm64/elf_hwcaps.txt

+4 −0
Original line number Diff line number Diff line
@@ -135,6 +135,10 @@ HWCAP_DCPOP 


    Functionality implied by ID_AA64ISAR1_EL1.DPB == 0b0001.



HWCAP2_DCPODP



    Functionality implied by ID_AA64ISAR1_EL1.DPB == 0b0010.



HWCAP_SHA3



    Functionality implied by ID_AA64ISAR0_EL1.SHA3 == 0b0001.

arch/arm64/include/asm/hwcap.h

+1 −0
Original line number Diff line number Diff line
@@ -88,6 +88,7 @@ 
#define KERNEL_HWCAP_PACG		__khwcap_feature(PACG)



#define __khwcap2_feature(x)		(const_ilog2(HWCAP2_ ## x) + 32)

#define KERNEL_HWCAP_DCPODP		__khwcap2_feature(DCPODP)



/*

 * This yields a mask that user programs can use to figure out what

arch/arm64/include/uapi/asm/hwcap.h

+5 −0
Original line number Diff line number Diff line
@@ -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 */

arch/arm64/kernel/cpufeature.c

+1 −0
Original line number Diff line number Diff line
@@ -1591,6 +1591,7 @@ 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),

arch/arm64/kernel/cpuinfo.c

+1 −0
Original line number Diff line number Diff line
@@ -85,6 +85,7 @@ static const char *const hwcap_str[] = { 
	"sb",

	"paca",

	"pacg",

	"dcpodp",

	NULL

};

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