From aaba098fe6ce594ae6f963dc041be6307e499f19 Mon Sep 17 00:00:00 2001 From: Andrew Murray Date: Tue, 9 Apr 2019 10:52:40 +0100 Subject: arm64: HWCAP: add support for AT_HWCAP2 As we will exhaust the first 32 bits of AT_HWCAP let's start exposing AT_HWCAP2 to userspace to give us up to 64 caps. Whilst it's possible to use the remaining 32 bits of AT_HWCAP, we prefer to expand into AT_HWCAP2 in order to provide a consistent view to userspace between ILP32 and LP64. However internal to the kernel we prefer to continue to use the full space of elf_hwcap. To reduce complexity and allow for future expansion, we now represent hwcaps in the kernel as ordinals and use a KERNEL_HWCAP_ prefix. This allows us to support automatic feature based module loading for all our hwcaps. We introduce cpu_set_feature to set hwcaps which complements the existing cpu_have_feature helper. These helpers allow us to clean up existing direct uses of elf_hwcap and reduce any future effort required to move beyond 64 caps. For convenience we also introduce cpu_{have,set}_named_feature which makes use of the cpu_feature macro to allow providing a hwcap name without a {KERNEL_}HWCAP_ prefix. Signed-off-by: Andrew Murray [will: use const_ilog2() and tweak documentation] Signed-off-by: Will Deacon --- arch/arm64/crypto/crct10dif-ce-glue.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'arch/arm64/crypto/crct10dif-ce-glue.c') diff --git a/arch/arm64/crypto/crct10dif-ce-glue.c b/arch/arm64/crypto/crct10dif-ce-glue.c index dd325829ee44..e81d5bd555c0 100644 --- a/arch/arm64/crypto/crct10dif-ce-glue.c +++ b/arch/arm64/crypto/crct10dif-ce-glue.c @@ -101,7 +101,7 @@ static struct shash_alg crc_t10dif_alg[] = {{ static int __init crc_t10dif_mod_init(void) { - if (elf_hwcap & HWCAP_PMULL) + if (cpu_have_named_feature(PMULL)) return crypto_register_shashes(crc_t10dif_alg, ARRAY_SIZE(crc_t10dif_alg)); else @@ -111,7 +111,7 @@ static int __init crc_t10dif_mod_init(void) static void __exit crc_t10dif_mod_exit(void) { - if (elf_hwcap & HWCAP_PMULL) + if (cpu_have_named_feature(PMULL)) crypto_unregister_shashes(crc_t10dif_alg, ARRAY_SIZE(crc_t10dif_alg)); else -- cgit v1.2.3-59-g8ed1b