[PATCH v2 10/22] arm64: Cleanup mixed endian support detection

From: Suzuki K. Poulose
Date: Mon Oct 05 2015 - 13:08:47 EST


Make use of the system wide safe register to decide the support
for mixed endian.

Signed-off-by: Suzuki K. Poulose <suzuki.poulose@xxxxxxx>
---
arch/arm64/kernel/cpufeature.c | 32 ++++++++++----------------------
1 file changed, 10 insertions(+), 22 deletions(-)

diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index a4eff72..3506876 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -24,7 +24,6 @@
#include <asm/processor.h>
#include <asm/sysreg.h>

-static bool mixed_endian_el0 = true;
unsigned long elf_hwcap __read_mostly;
EXPORT_SYMBOL_GPL(elf_hwcap);

@@ -42,22 +41,6 @@ unsigned int compat_elf_hwcap2 __read_mostly;

DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);

-
-bool cpu_supports_mixed_endian_el0(void)
-{
- return id_aa64mmfr0_mixed_endian_el0(read_cpuid(ID_AA64MMFR0_EL1));
-}
-
-bool system_supports_mixed_endian_el0(void)
-{
- return mixed_endian_el0;
-}
-
-static void update_mixed_endian_el0_support(struct cpuinfo_arm64 *info)
-{
- mixed_endian_el0 &= id_aa64mmfr0_mixed_endian_el0(info->reg_id_aa64mmfr0);
-}
-
#define ARM64_FTR_BITS(ftr_strict, ftr_type, ftr_shift, ftr_width, ftr_safe_val) \
{ \
.strict = ftr_strict, \
@@ -438,9 +421,6 @@ void __init init_cpu_features(struct cpuinfo_arm64 *info)
init_cpu_ftr_reg(SYS_MVFR0_EL1, info->reg_mvfr0);
init_cpu_ftr_reg(SYS_MVFR1_EL1, info->reg_mvfr1);
init_cpu_ftr_reg(SYS_MVFR2_EL1, info->reg_mvfr2);
-
- /* This will be removed later, once we start using the infrastructure */
- update_mixed_endian_el0_support(info);
}

static void update_cpu_ftr_reg(struct arm64_ftr_reg *reg, u64 new)
@@ -590,8 +570,6 @@ void update_cpu_features(int cpu,
*/
WARN_TAINT_ONCE(taint, TAINT_CPU_OUT_OF_SPEC,
"Unsupported CPU feature variation.\n");
-
- update_mixed_endian_el0_support(info);
}

u64 read_system_reg(u32 id)
@@ -681,6 +659,16 @@ void check_local_cpu_features(void)
check_cpu_capabilities(arm64_features, "detected feature:");
}

+bool cpu_supports_mixed_endian_el0(void)
+{
+ return id_aa64mmfr0_mixed_endian_el0(read_cpuid(ID_AA64MMFR0_EL1));
+}
+
+bool system_supports_mixed_endian_el0(void)
+{
+ return id_aa64mmfr0_mixed_endian_el0(read_system_reg(SYS_ID_AA64MMFR0_EL1));
+}
+
void __init setup_cpu_features(void)
{
u64 features;
--
1.7.9.5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/