[PATCH v3 3/5] arm64: Extract feature parsing code from cpu_errata.c
Marc Zyngier
marc.zyngier at arm.com
Fri Mar 27 06:09:23 PDT 2015
As we detect more architectural features at runtime, it makes
sense to reuse the existing framework whilst avoiding to call
a feature an erratum...
This patch extract the core capability parsing, moves it into
a new file (cpufeature.c), and let the CPU errata detection code
use it.
Reviewed-by: Andre Przywara <andre.przywara at arm.com>
Acked-by: Will Deacon <will.deacon at arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
---
arch/arm64/include/asm/cpufeature.h | 15 ++++++++++++
arch/arm64/kernel/Makefile | 2 +-
arch/arm64/kernel/cpu_errata.c | 36 ++++------------------------
arch/arm64/kernel/cpufeature.c | 47 +++++++++++++++++++++++++++++++++++++
arch/arm64/kernel/cpuinfo.c | 1 +
5 files changed, 68 insertions(+), 33 deletions(-)
create mode 100644 arch/arm64/kernel/cpufeature.c
diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h
index b6c16d5..6ae35d1 100644
--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h
@@ -28,6 +28,18 @@
#ifndef __ASSEMBLY__
+struct arm64_cpu_capabilities {
+ const char *desc;
+ u16 capability;
+ bool (*matches)(const struct arm64_cpu_capabilities *);
+ union {
+ struct { /* To be used for erratum handling only */
+ u32 midr_model;
+ u32 midr_range_min, midr_range_max;
+ };
+ };
+};
+
extern DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
static inline bool cpu_have_feature(unsigned int num)
@@ -51,7 +63,10 @@ static inline void cpus_set_cap(unsigned int num)
__set_bit(num, cpu_hwcaps);
}
+void check_cpu_capabilities(const struct arm64_cpu_capabilities *caps,
+ const char *info);
void check_local_cpu_errata(void);
+void check_local_cpu_features(void);
bool cpu_supports_mixed_endian_el0(void);
bool system_supports_mixed_endian_el0(void);
diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
index d5e7074..b12e15b 100644
--- a/arch/arm64/kernel/Makefile
+++ b/arch/arm64/kernel/Makefile
@@ -17,7 +17,7 @@ arm64-obj-y := debug-monitors.o entry.o irq.o fpsimd.o \
sys.o stacktrace.o time.o traps.o io.o vdso.o \
hyp-stub.o psci.o psci-call.o cpu_ops.o insn.o \
return_address.o cpuinfo.o cpu_errata.o \
- alternative.o cacheinfo.o
+ cpufeature.o alternative.o cacheinfo.o
arm64-obj-$(CONFIG_COMPAT) += sys32.o kuser32.o signal32.o \
sys_compat.o entry32.o \
diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
index fa62637..a66f4fa 100644
--- a/arch/arm64/kernel/cpu_errata.c
+++ b/arch/arm64/kernel/cpu_errata.c
@@ -16,8 +16,6 @@
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
-#define pr_fmt(fmt) "alternatives: " fmt
-
#include <linux/types.h>
#include <asm/cpu.h>
#include <asm/cputype.h>
@@ -26,27 +24,11 @@
#define MIDR_CORTEX_A53 MIDR_CPU_PART(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A53)
#define MIDR_CORTEX_A57 MIDR_CPU_PART(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A57)
-/*
- * Add a struct or another datatype to the union below if you need
- * different means to detect an affected CPU.
- */
-struct arm64_cpu_capabilities {
- const char *desc;
- u16 capability;
- bool (*is_affected)(struct arm64_cpu_capabilities *);
- union {
- struct {
- u32 midr_model;
- u32 midr_range_min, midr_range_max;
- };
- };
-};
-
#define CPU_MODEL_MASK (MIDR_IMPLEMENTOR_MASK | MIDR_PARTNUM_MASK | \
MIDR_ARCHITECTURE_MASK)
static bool __maybe_unused
-is_affected_midr_range(struct arm64_cpu_capabilities *entry)
+is_affected_midr_range(const struct arm64_cpu_capabilities *entry)
{
u32 midr = read_cpuid_id();
@@ -59,12 +41,12 @@ is_affected_midr_range(struct arm64_cpu_capabilities *entry)
}
#define MIDR_RANGE(model, min, max) \
- .is_affected = is_affected_midr_range, \
+ .matches = is_affected_midr_range, \
.midr_model = model, \
.midr_range_min = min, \
.midr_range_max = max
-struct arm64_cpu_capabilities arm64_errata[] = {
+const struct arm64_cpu_capabilities arm64_errata[] = {
#if defined(CONFIG_ARM64_ERRATUM_826319) || \
defined(CONFIG_ARM64_ERRATUM_827319) || \
defined(CONFIG_ARM64_ERRATUM_824069)
@@ -97,15 +79,5 @@ struct arm64_cpu_capabilities arm64_errata[] = {
void check_local_cpu_errata(void)
{
- struct arm64_cpu_capabilities *cpus = arm64_errata;
- int i;
-
- for (i = 0; cpus[i].desc; i++) {
- if (!cpus[i].is_affected(&cpus[i]))
- continue;
-
- if (!cpus_have_cap(cpus[i].capability))
- pr_info("enabling workaround for %s\n", cpus[i].desc);
- cpus_set_cap(cpus[i].capability);
- }
+ check_cpu_capabilities(arm64_errata, "enabling workaround for");
}
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
new file mode 100644
index 0000000..3d9967e
--- /dev/null
+++ b/arch/arm64/kernel/cpufeature.c
@@ -0,0 +1,47 @@
+/*
+ * Contains CPU feature definitions
+ *
+ * Copyright (C) 2015 ARM Ltd.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define pr_fmt(fmt) "alternatives: " fmt
+
+#include <linux/types.h>
+#include <asm/cpu.h>
+#include <asm/cpufeature.h>
+
+static const struct arm64_cpu_capabilities arm64_features[] = {
+ {},
+};
+
+void check_cpu_capabilities(const struct arm64_cpu_capabilities *caps,
+ const char *info)
+{
+ int i;
+
+ for (i = 0; caps[i].desc; i++) {
+ if (!caps[i].matches(&caps[i]))
+ continue;
+
+ if (!cpus_have_cap(caps[i].capability))
+ pr_info("%s %s\n", info, caps[i].desc);
+ cpus_set_cap(caps[i].capability);
+ }
+}
+
+void check_local_cpu_features(void)
+{
+ check_cpu_capabilities(arm64_features, "detected feature");
+}
diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c
index 9298556..75d5a86 100644
--- a/arch/arm64/kernel/cpuinfo.c
+++ b/arch/arm64/kernel/cpuinfo.c
@@ -236,6 +236,7 @@ static void __cpuinfo_store_cpu(struct cpuinfo_arm64 *info)
cpuinfo_detect_icache_policy(info);
check_local_cpu_errata();
+ check_local_cpu_features();
update_cpu_features(info);
}
--
2.1.4
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