[PATCH 2/3] arm64/setup: Use ID_AA64ISAR0_EL1_.* macros

Alexander Kuleshov kuleshovmail at gmail.com
Thu Sep 3 11:12:52 PDT 2015


The 26d75e67c commit (arm64/cpufeature.h: Add macros for a cpu features
testing) provides set of macros for the testing processor's crypto features.
Let's use these macros instead of direct calculation.

Signed-off-by: Alexander Kuleshov <kuleshovmail at gmail.com>
---
 arch/arm64/kernel/setup.c | 29 +++++++++--------------------
 1 file changed, 9 insertions(+), 20 deletions(-)

diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
index 926ae8d..a3faf4f 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c
@@ -250,33 +250,22 @@ static void __init setup_processor(void)
 
 	/*
 	 * ID_AA64ISAR0_EL1 contains 4-bit wide signed feature blocks.
-	 * The blocks we test below represent incremental functionality
-	 * for non-negative values. Negative values are reserved.
 	 */
 	features = read_cpuid(ID_AA64ISAR0_EL1);
-	block = (features >> 4) & 0xf;
-	if (!(block & 0x8)) {
-		switch (block) {
-		default:
-		case 2:
-			elf_hwcap |= HWCAP_PMULL;
-		case 1:
-			elf_hwcap |= HWCAP_AES;
-		case 0:
-			break;
-		}
-	}
 
-	block = (features >> 8) & 0xf;
-	if (block && !(block & 0x8))
+	if (ID_AA64ISAR0_EL1_AES(features))
+		elf_hwcap |= HWCAP_AES;
+
+	if (ID_AA64ISAR0_EL1_PMULL(features))
+		elf_hwcap |= HWCAP_PMULL;
+
+	if (ID_AA64ISAR0_EL1_SHA1(features))
 		elf_hwcap |= HWCAP_SHA1;
 
-	block = (features >> 12) & 0xf;
-	if (block && !(block & 0x8))
+	if (ID_AA64ISAR0_EL1_SHA2(features))
 		elf_hwcap |= HWCAP_SHA2;
 
-	block = (features >> 16) & 0xf;
-	if (block && !(block & 0x8))
+	if (ID_AA64ISAR0_EL1_CRC32(features))
 		elf_hwcap |= HWCAP_CRC32;
 
 #ifdef CONFIG_COMPAT
-- 
2.5.0




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