Commit 309585b0 authored by Will Deacon's avatar Will Deacon
Browse files

arm64: elf: use cpuid_feature_extract_field for hwcap detection 



cpuid_feature_extract_field takes care of the fiddly ID register
field sign-extension, so use that instead of rolling our own version.

Signed-off-by: default avatarWill Deacon <will.deacon@arm.com>
parent 2e94da13

arch/arm64/kernel/setup.c

+15 −20
Original line number Diff line number Diff line
@@ -223,7 +223,8 @@ void __init up_late_init(void) 


static void __init setup_processor(void)

{

	u64 features, block;

	u64 features;

	s64 block;

	u32 cwg;

	int cls;
@@ -253,8 +254,8 @@ static void __init setup_processor(void) 
	 * for non-negative values. Negative values are reserved.

	 */

	features = read_cpuid(ID_AA64ISAR0_EL1);

	block = (features >> 4) & 0xf;

	if (!(block & 0x8)) {

	block = cpuid_feature_extract_field(features, 4);

	if (block > 0) {

		switch (block) {

		default:

		case 2:
@@ -266,20 +267,17 @@ static void __init setup_processor(void) 
		}

	}



	block = (features >> 8) & 0xf;

	if (block && !(block & 0x8))

	if (cpuid_feature_extract_field(features, 8) > 0)

		elf_hwcap |= HWCAP_SHA1;



	block = (features >> 12) & 0xf;

	if (block && !(block & 0x8))

	if (cpuid_feature_extract_field(features, 12) > 0)

		elf_hwcap |= HWCAP_SHA2;



	block = (features >> 16) & 0xf;

	if (block && !(block & 0x8))

	if (cpuid_feature_extract_field(features, 16) > 0)

		elf_hwcap |= HWCAP_CRC32;



	block = (features >> 20) & 0xf;

	if (!(block & 0x8)) {

	block = cpuid_feature_extract_field(features, 20);

	if (block > 0) {

		switch (block) {

		default:

		case 2:
@@ -294,11 +292,11 @@ static void __init setup_processor(void) 
#ifdef CONFIG_COMPAT

	/*

	 * ID_ISAR5_EL1 carries similar information as above, but pertaining to

	 * the Aarch32 32-bit execution state.

	 * the AArch32 32-bit execution state.

	 */

	features = read_cpuid(ID_ISAR5_EL1);

	block = (features >> 4) & 0xf;

	if (!(block & 0x8)) {

	block = cpuid_feature_extract_field(features, 4);

	if (block > 0) {

		switch (block) {

		default:

		case 2:
@@ -310,16 +308,13 @@ static void __init setup_processor(void) 
		}

	}



	block = (features >> 8) & 0xf;

	if (block && !(block & 0x8))

	if (cpuid_feature_extract_field(features, 8) > 0)

		compat_elf_hwcap2 |= COMPAT_HWCAP2_SHA1;



	block = (features >> 12) & 0xf;

	if (block && !(block & 0x8))

	if (cpuid_feature_extract_field(features, 12) > 0)

		compat_elf_hwcap2 |= COMPAT_HWCAP2_SHA2;



	block = (features >> 16) & 0xf;

	if (block && !(block & 0x8))

	if (cpuid_feature_extract_field(features, 16) > 0)

		compat_elf_hwcap2 |= COMPAT_HWCAP2_CRC32;

#endif

}