linux-stable/arch/arm64/include/asm/cpu.h
Dave Martin 2e0f2478ea arm64/sve: Probe SVE capabilities and usable vector lengths
This patch uses the cpufeatures framework to determine common SVE
capabilities and vector lengths, and configures the runtime SVE
support code appropriately.

ZCR_ELx is not really a feature register, but it is convenient to
use it as a template for recording the maximum vector length
supported by a CPU, using the LEN field.  This field is similar to
a feature field in that it is a contiguous bitfield for which we
want to determine the minimum system-wide value.  This patch adds
ZCR as a pseudo-register in cpuinfo/cpufeatures, with appropriate
custom code to populate it.  Finding the minimum supported value of
the LEN field is left to the cpufeatures framework in the usual
way.

The meaning of ID_AA64ZFR0_EL1 is not architecturally defined yet,
so for now we just require it to be zero.

Note that much of this code is dormant and SVE still won't be used
yet, since system_supports_sve() remains hardwired to false.

Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-11-03 15:24:17 +00:00

77 lines
1.8 KiB
C

/*
* Copyright (C) 2014 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/>.
*/
#ifndef __ASM_CPU_H
#define __ASM_CPU_H
#include <linux/cpu.h>
#include <linux/init.h>
#include <linux/percpu.h>
/*
* Records attributes of an individual CPU.
*/
struct cpuinfo_arm64 {
struct cpu cpu;
struct kobject kobj;
u32 reg_ctr;
u32 reg_cntfrq;
u32 reg_dczid;
u32 reg_midr;
u32 reg_revidr;
u64 reg_id_aa64dfr0;
u64 reg_id_aa64dfr1;
u64 reg_id_aa64isar0;
u64 reg_id_aa64isar1;
u64 reg_id_aa64mmfr0;
u64 reg_id_aa64mmfr1;
u64 reg_id_aa64mmfr2;
u64 reg_id_aa64pfr0;
u64 reg_id_aa64pfr1;
u64 reg_id_aa64zfr0;
u32 reg_id_dfr0;
u32 reg_id_isar0;
u32 reg_id_isar1;
u32 reg_id_isar2;
u32 reg_id_isar3;
u32 reg_id_isar4;
u32 reg_id_isar5;
u32 reg_id_mmfr0;
u32 reg_id_mmfr1;
u32 reg_id_mmfr2;
u32 reg_id_mmfr3;
u32 reg_id_pfr0;
u32 reg_id_pfr1;
u32 reg_mvfr0;
u32 reg_mvfr1;
u32 reg_mvfr2;
/* pseudo-ZCR for recording maximum ZCR_EL1 LEN value: */
u64 reg_zcr;
};
DECLARE_PER_CPU(struct cpuinfo_arm64, cpu_data);
void cpuinfo_store_cpu(void);
void __init cpuinfo_store_boot_cpu(void);
void __init init_cpu_features(struct cpuinfo_arm64 *info);
void update_cpu_features(int cpu, struct cpuinfo_arm64 *info,
struct cpuinfo_arm64 *boot);
#endif /* __ASM_CPU_H */