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author | 2020-01-22 11:38:53 +0000 | |
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committer | 2020-01-22 11:38:53 +0000 | |
commit | bc206065944e2d6bd917e719dc897ffff8dbbca8 (patch) | |
tree | c085dc23f5b52e0621b164f0d5fd205d8bd50b47 /arch/arm64/include | |
parent | Merge branch 'for-next/errata' into for-next/core (diff) | |
parent | arm64: Use v8.5-RNG entropy for KASLR seed (diff) | |
download | linux-bc206065944e2d6bd917e719dc897ffff8dbbca8.tar.gz linux-bc206065944e2d6bd917e719dc897ffff8dbbca8.tar.bz2 linux-bc206065944e2d6bd917e719dc897ffff8dbbca8.zip |
Merge branch 'for-next/rng' into for-next/core
* for-next/rng: (2 commits)
arm64: Use v8.5-RNG entropy for KASLR seed
...
Diffstat (limited to 'arch/arm64/include')
-rw-r--r-- | arch/arm64/include/asm/archrandom.h | 75 | ||||
-rw-r--r-- | arch/arm64/include/asm/cpucaps.h | 3 | ||||
-rw-r--r-- | arch/arm64/include/asm/hwcap.h | 3 | ||||
-rw-r--r-- | arch/arm64/include/asm/sysreg.h | 4 | ||||
-rw-r--r-- | arch/arm64/include/uapi/asm/hwcap.h | 1 |
5 files changed, 84 insertions, 2 deletions
diff --git a/arch/arm64/include/asm/archrandom.h b/arch/arm64/include/asm/archrandom.h new file mode 100644 index 000000000000..3fe02da70004 --- /dev/null +++ b/arch/arm64/include/asm/archrandom.h @@ -0,0 +1,75 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_ARCHRANDOM_H +#define _ASM_ARCHRANDOM_H + +#ifdef CONFIG_ARCH_RANDOM + +#include <linux/random.h> +#include <asm/cpufeature.h> + +static inline bool __arm64_rndr(unsigned long *v) +{ + bool ok; + + /* + * Reads of RNDR set PSTATE.NZCV to 0b0000 on success, + * and set PSTATE.NZCV to 0b0100 otherwise. + */ + asm volatile( + __mrs_s("%0", SYS_RNDR_EL0) "\n" + " cset %w1, ne\n" + : "=r" (*v), "=r" (ok) + : + : "cc"); + + return ok; +} + +static inline bool __must_check arch_get_random_long(unsigned long *v) +{ + return false; +} + +static inline bool __must_check arch_get_random_int(unsigned int *v) +{ + return false; +} + +static inline bool __must_check arch_get_random_seed_long(unsigned long *v) +{ + /* + * Only support the generic interface after we have detected + * the system wide capability, avoiding complexity with the + * cpufeature code and with potential scheduling between CPUs + * with and without the feature. + */ + if (!cpus_have_const_cap(ARM64_HAS_RNG)) + return false; + + return __arm64_rndr(v); +} + + +static inline bool __must_check arch_get_random_seed_int(unsigned int *v) +{ + unsigned long val; + bool ok = arch_get_random_seed_long(&val); + + *v = val; + return ok; +} + +static inline bool __init __early_cpu_has_rndr(void) +{ + /* Open code as we run prior to the first call to cpufeature. */ + unsigned long ftr = read_sysreg_s(SYS_ID_AA64ISAR0_EL1); + return (ftr >> ID_AA64ISAR0_RNDR_SHIFT) & 0xf; +} + +#else + +static inline bool __arm64_rndr(unsigned long *v) { return false; } +static inline bool __init __early_cpu_has_rndr(void) { return false; } + +#endif /* CONFIG_ARCH_RANDOM */ +#endif /* _ASM_ARCHRANDOM_H */ diff --git a/arch/arm64/include/asm/cpucaps.h b/arch/arm64/include/asm/cpucaps.h index a61c33611e39..865e0253fc1e 100644 --- a/arch/arm64/include/asm/cpucaps.h +++ b/arch/arm64/include/asm/cpucaps.h @@ -57,7 +57,8 @@ #define ARM64_WORKAROUND_1542419 47 #define ARM64_WORKAROUND_SPECULATIVE_AT_NVHE 48 #define ARM64_HAS_E0PD 49 +#define ARM64_HAS_RNG 50 -#define ARM64_NCAPS 50 +#define ARM64_NCAPS 51 #endif /* __ASM_CPUCAPS_H */ diff --git a/arch/arm64/include/asm/hwcap.h b/arch/arm64/include/asm/hwcap.h index fcb390ea29ea..0f00265248b5 100644 --- a/arch/arm64/include/asm/hwcap.h +++ b/arch/arm64/include/asm/hwcap.h @@ -91,8 +91,9 @@ #define KERNEL_HWCAP_SVEF64MM __khwcap2_feature(SVEF64MM) #define KERNEL_HWCAP_SVEBF16 __khwcap2_feature(SVEBF16) #define KERNEL_HWCAP_I8MM __khwcap2_feature(I8MM) -#define KERNEL_HWCAP_DGH __khwcap2_feature(DGH) #define KERNEL_HWCAP_BF16 __khwcap2_feature(BF16) +#define KERNEL_HWCAP_DGH __khwcap2_feature(DGH) +#define KERNEL_HWCAP_RNG __khwcap2_feature(RNG) /* * This yields a mask that user programs can use to figure out what diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h index a2d3271b64bd..b91570ff9db1 100644 --- a/arch/arm64/include/asm/sysreg.h +++ b/arch/arm64/include/asm/sysreg.h @@ -366,6 +366,9 @@ #define SYS_CTR_EL0 sys_reg(3, 3, 0, 0, 1) #define SYS_DCZID_EL0 sys_reg(3, 3, 0, 0, 7) +#define SYS_RNDR_EL0 sys_reg(3, 3, 2, 4, 0) +#define SYS_RNDRRS_EL0 sys_reg(3, 3, 2, 4, 1) + #define SYS_PMCR_EL0 sys_reg(3, 3, 9, 12, 0) #define SYS_PMCNTENSET_EL0 sys_reg(3, 3, 9, 12, 1) #define SYS_PMCNTENCLR_EL0 sys_reg(3, 3, 9, 12, 2) @@ -552,6 +555,7 @@ #define MAIR_ATTRIDX(attr, idx) ((attr) << ((idx) * 8)) /* id_aa64isar0 */ +#define ID_AA64ISAR0_RNDR_SHIFT 60 #define ID_AA64ISAR0_TS_SHIFT 52 #define ID_AA64ISAR0_FHM_SHIFT 48 #define ID_AA64ISAR0_DP_SHIFT 44 diff --git a/arch/arm64/include/uapi/asm/hwcap.h b/arch/arm64/include/uapi/asm/hwcap.h index e6dad5924703..7752d93bb50f 100644 --- a/arch/arm64/include/uapi/asm/hwcap.h +++ b/arch/arm64/include/uapi/asm/hwcap.h @@ -72,5 +72,6 @@ #define HWCAP2_I8MM (1 << 13) #define HWCAP2_BF16 (1 << 14) #define HWCAP2_DGH (1 << 15) +#define HWCAP2_RNG (1 << 16) #endif /* _UAPI__ASM_HWCAP_H */ |