[PATCHv4 04/24] arm64: Move cpu feature detection code

From: Suzuki K. Poulose
Date: Mon Oct 19 2015 - 09:07:00 EST


This patch moves the CPU feature detection code from
arch/arm64/kernel/{setup.c to cpufeature.c}

The plan is to consolidate all the CPU feature handling
in cpufeature.c.

Apart from changing pr_fmt from "alternatives" to "cpu features",
there are no functional changes.

Signed-off-by: Suzuki K. Poulose <suzuki.poulose@xxxxxxx>
---
arch/arm64/kernel/cpufeature.c | 110 +++++++++++++++++++++++++++++++++++++++-
arch/arm64/kernel/setup.c | 107 --------------------------------------
2 files changed, 109 insertions(+), 108 deletions(-)

diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 3c9aed3..e49be15 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -16,13 +16,31 @@
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/

-#define pr_fmt(fmt) "alternatives: " fmt
+#define pr_fmt(fmt) "CPU features: " fmt

#include <linux/types.h>
#include <asm/cpu.h>
#include <asm/cpufeature.h>
#include <asm/processor.h>

+unsigned long elf_hwcap __read_mostly;
+EXPORT_SYMBOL_GPL(elf_hwcap);
+
+#ifdef CONFIG_COMPAT
+#define COMPAT_ELF_HWCAP_DEFAULT \
+ (COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\
+ COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\
+ COMPAT_HWCAP_TLS|COMPAT_HWCAP_VFP|\
+ COMPAT_HWCAP_VFPv3|COMPAT_HWCAP_VFPv4|\
+ COMPAT_HWCAP_NEON|COMPAT_HWCAP_IDIV|\
+ COMPAT_HWCAP_LPAE)
+unsigned int compat_elf_hwcap __read_mostly = COMPAT_ELF_HWCAP_DEFAULT;
+unsigned int compat_elf_hwcap2 __read_mostly;
+#endif
+
+DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
+
+
static bool
feature_matches(u64 reg, const struct arm64_cpu_capabilities *entry)
{
@@ -100,3 +118,93 @@ void check_local_cpu_features(void)
{
check_cpu_capabilities(arm64_features, "detected feature:");
}
+
+void __init setup_cpu_features(void)
+{
+ u64 features;
+ s64 block;
+ u32 cwg;
+ int cls;
+
+ /*
+ * Check for sane CTR_EL0.CWG value.
+ */
+ cwg = cache_type_cwg();
+ cls = cache_line_size();
+ if (!cwg)
+ pr_warn("No Cache Writeback Granule information, assuming cache line size %d\n",
+ cls);
+ if (L1_CACHE_BYTES < cls)
+ pr_warn("L1_CACHE_BYTES smaller than the Cache Writeback Granule (%d < %d)\n",
+ L1_CACHE_BYTES, cls);
+
+ /*
+ * 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 = cpuid_feature_extract_field(features, 4);
+ if (block > 0) {
+ switch (block) {
+ default:
+ case 2:
+ elf_hwcap |= HWCAP_PMULL;
+ case 1:
+ elf_hwcap |= HWCAP_AES;
+ case 0:
+ break;
+ }
+ }
+
+ if (cpuid_feature_extract_field(features, 8) > 0)
+ elf_hwcap |= HWCAP_SHA1;
+
+ if (cpuid_feature_extract_field(features, 12) > 0)
+ elf_hwcap |= HWCAP_SHA2;
+
+ if (cpuid_feature_extract_field(features, 16) > 0)
+ elf_hwcap |= HWCAP_CRC32;
+
+ block = cpuid_feature_extract_field(features, 20);
+ if (block > 0) {
+ switch (block) {
+ default:
+ case 2:
+ elf_hwcap |= HWCAP_ATOMICS;
+ case 1:
+ /* RESERVED */
+ case 0:
+ break;
+ }
+ }
+
+#ifdef CONFIG_COMPAT
+ /*
+ * ID_ISAR5_EL1 carries similar information as above, but pertaining to
+ * the AArch32 32-bit execution state.
+ */
+ features = read_cpuid(ID_ISAR5_EL1);
+ block = cpuid_feature_extract_field(features, 4);
+ if (block > 0) {
+ switch (block) {
+ default:
+ case 2:
+ compat_elf_hwcap2 |= COMPAT_HWCAP2_PMULL;
+ case 1:
+ compat_elf_hwcap2 |= COMPAT_HWCAP2_AES;
+ case 0:
+ break;
+ }
+ }
+
+ if (cpuid_feature_extract_field(features, 8) > 0)
+ compat_elf_hwcap2 |= COMPAT_HWCAP2_SHA1;
+
+ if (cpuid_feature_extract_field(features, 12) > 0)
+ compat_elf_hwcap2 |= COMPAT_HWCAP2_SHA2;
+
+ if (cpuid_feature_extract_field(features, 16) > 0)
+ compat_elf_hwcap2 |= COMPAT_HWCAP2_CRC32;
+#endif
+}
diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
index 47e0051..baf0da8 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c
@@ -65,23 +65,6 @@
#include <asm/efi.h>
#include <asm/xen/hypervisor.h>

-unsigned long elf_hwcap __read_mostly;
-EXPORT_SYMBOL_GPL(elf_hwcap);
-
-#ifdef CONFIG_COMPAT
-#define COMPAT_ELF_HWCAP_DEFAULT \
- (COMPAT_HWCAP_HALF|COMPAT_HWCAP_THUMB|\
- COMPAT_HWCAP_FAST_MULT|COMPAT_HWCAP_EDSP|\
- COMPAT_HWCAP_TLS|COMPAT_HWCAP_VFP|\
- COMPAT_HWCAP_VFPv3|COMPAT_HWCAP_VFPv4|\
- COMPAT_HWCAP_NEON|COMPAT_HWCAP_IDIV|\
- COMPAT_HWCAP_LPAE)
-unsigned int compat_elf_hwcap __read_mostly = COMPAT_ELF_HWCAP_DEFAULT;
-unsigned int compat_elf_hwcap2 __read_mostly;
-#endif
-
-DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
-
phys_addr_t __fdt_pointer __initdata;

/*
@@ -196,96 +179,6 @@ static void __init smp_build_mpidr_hash(void)
__flush_dcache_area(&mpidr_hash, sizeof(struct mpidr_hash));
}

-void __init setup_cpu_features(void)
-{
- u64 features;
- s64 block;
- u32 cwg;
- int cls;
-
- /*
- * Check for sane CTR_EL0.CWG value.
- */
- cwg = cache_type_cwg();
- cls = cache_line_size();
- if (!cwg)
- pr_warn("No Cache Writeback Granule information, assuming cache line size %d\n",
- cls);
- if (L1_CACHE_BYTES < cls)
- pr_warn("L1_CACHE_BYTES smaller than the Cache Writeback Granule (%d < %d)\n",
- L1_CACHE_BYTES, cls);
-
- /*
- * 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 = cpuid_feature_extract_field(features, 4);
- if (block > 0) {
- switch (block) {
- default:
- case 2:
- elf_hwcap |= HWCAP_PMULL;
- case 1:
- elf_hwcap |= HWCAP_AES;
- case 0:
- break;
- }
- }
-
- if (cpuid_feature_extract_field(features, 8) > 0)
- elf_hwcap |= HWCAP_SHA1;
-
- if (cpuid_feature_extract_field(features, 12) > 0)
- elf_hwcap |= HWCAP_SHA2;
-
- if (cpuid_feature_extract_field(features, 16) > 0)
- elf_hwcap |= HWCAP_CRC32;
-
- block = cpuid_feature_extract_field(features, 20);
- if (block > 0) {
- switch (block) {
- default:
- case 2:
- elf_hwcap |= HWCAP_ATOMICS;
- case 1:
- /* RESERVED */
- case 0:
- break;
- }
- }
-
-#ifdef CONFIG_COMPAT
- /*
- * ID_ISAR5_EL1 carries similar information as above, but pertaining to
- * the AArch32 32-bit execution state.
- */
- features = read_cpuid(ID_ISAR5_EL1);
- block = cpuid_feature_extract_field(features, 4);
- if (block > 0) {
- switch (block) {
- default:
- case 2:
- compat_elf_hwcap2 |= COMPAT_HWCAP2_PMULL;
- case 1:
- compat_elf_hwcap2 |= COMPAT_HWCAP2_AES;
- case 0:
- break;
- }
- }
-
- if (cpuid_feature_extract_field(features, 8) > 0)
- compat_elf_hwcap2 |= COMPAT_HWCAP2_SHA1;
-
- if (cpuid_feature_extract_field(features, 12) > 0)
- compat_elf_hwcap2 |= COMPAT_HWCAP2_SHA2;
-
- if (cpuid_feature_extract_field(features, 16) > 0)
- compat_elf_hwcap2 |= COMPAT_HWCAP2_CRC32;
-#endif
-}
-
static void __init setup_machine_fdt(phys_addr_t dt_phys)
{
void *dt_virt = fixmap_remap_fdt(dt_phys);
--
1.7.9.5

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