linux/arch/arm64/kernel/cpuinfo.c
Dave Martin 9299b24712 arm64: Constify hwcap name string arrays
The hwcap string arrays used for generating the contents of
/proc/cpuinfo are currently arrays of non-const pointers.

There's no need for these pointers to be mutable, so this patch makes
them const so that they can be moved to .rodata.

Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-21 15:36:00 +01:00

249 lines
6.4 KiB
C

/*
* Record and handle CPU attributes.
*
* 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/>.
*/
#include <asm/arch_timer.h>
#include <asm/cachetype.h>
#include <asm/cpu.h>
#include <asm/cputype.h>
#include <asm/cpufeature.h>
#include <linux/bitops.h>
#include <linux/bug.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/personality.h>
#include <linux/preempt.h>
#include <linux/printk.h>
#include <linux/seq_file.h>
#include <linux/sched.h>
#include <linux/smp.h>
/*
* In case the boot CPU is hotpluggable, we record its initial state and
* current state separately. Certain system registers may contain different
* values depending on configuration at or after reset.
*/
DEFINE_PER_CPU(struct cpuinfo_arm64, cpu_data);
static struct cpuinfo_arm64 boot_cpu_data;
static char *icache_policy_str[] = {
[ICACHE_POLICY_RESERVED] = "RESERVED/UNKNOWN",
[ICACHE_POLICY_AIVIVT] = "AIVIVT",
[ICACHE_POLICY_VIPT] = "VIPT",
[ICACHE_POLICY_PIPT] = "PIPT",
};
unsigned long __icache_flags;
static const char *const hwcap_str[] = {
"fp",
"asimd",
"evtstrm",
"aes",
"pmull",
"sha1",
"sha2",
"crc32",
"atomics",
NULL
};
#ifdef CONFIG_COMPAT
static const char *const compat_hwcap_str[] = {
"swp",
"half",
"thumb",
"26bit",
"fastmult",
"fpa",
"vfp",
"edsp",
"java",
"iwmmxt",
"crunch",
"thumbee",
"neon",
"vfpv3",
"vfpv3d16",
"tls",
"vfpv4",
"idiva",
"idivt",
"vfpd32",
"lpae",
"evtstrm"
};
static const char *const compat_hwcap2_str[] = {
"aes",
"pmull",
"sha1",
"sha2",
"crc32",
NULL
};
#endif /* CONFIG_COMPAT */
static int c_show(struct seq_file *m, void *v)
{
int i, j;
for_each_online_cpu(i) {
struct cpuinfo_arm64 *cpuinfo = &per_cpu(cpu_data, i);
u32 midr = cpuinfo->reg_midr;
/*
* glibc reads /proc/cpuinfo to determine the number of
* online processors, looking for lines beginning with
* "processor". Give glibc what it expects.
*/
seq_printf(m, "processor\t: %d\n", i);
/*
* Dump out the common processor features in a single line.
* Userspace should read the hwcaps with getauxval(AT_HWCAP)
* rather than attempting to parse this, but there's a body of
* software which does already (at least for 32-bit).
*/
seq_puts(m, "Features\t:");
if (personality(current->personality) == PER_LINUX32) {
#ifdef CONFIG_COMPAT
for (j = 0; compat_hwcap_str[j]; j++)
if (compat_elf_hwcap & (1 << j))
seq_printf(m, " %s", compat_hwcap_str[j]);
for (j = 0; compat_hwcap2_str[j]; j++)
if (compat_elf_hwcap2 & (1 << j))
seq_printf(m, " %s", compat_hwcap2_str[j]);
#endif /* CONFIG_COMPAT */
} else {
for (j = 0; hwcap_str[j]; j++)
if (elf_hwcap & (1 << j))
seq_printf(m, " %s", hwcap_str[j]);
}
seq_puts(m, "\n");
seq_printf(m, "CPU implementer\t: 0x%02x\n",
MIDR_IMPLEMENTOR(midr));
seq_printf(m, "CPU architecture: 8\n");
seq_printf(m, "CPU variant\t: 0x%x\n", MIDR_VARIANT(midr));
seq_printf(m, "CPU part\t: 0x%03x\n", MIDR_PARTNUM(midr));
seq_printf(m, "CPU revision\t: %d\n\n", MIDR_REVISION(midr));
}
return 0;
}
static void *c_start(struct seq_file *m, loff_t *pos)
{
return *pos < 1 ? (void *)1 : NULL;
}
static void *c_next(struct seq_file *m, void *v, loff_t *pos)
{
++*pos;
return NULL;
}
static void c_stop(struct seq_file *m, void *v)
{
}
const struct seq_operations cpuinfo_op = {
.start = c_start,
.next = c_next,
.stop = c_stop,
.show = c_show
};
static void cpuinfo_detect_icache_policy(struct cpuinfo_arm64 *info)
{
unsigned int cpu = smp_processor_id();
u32 l1ip = CTR_L1IP(info->reg_ctr);
if (l1ip != ICACHE_POLICY_PIPT) {
/*
* VIPT caches are non-aliasing if the VA always equals the PA
* in all bit positions that are covered by the index. This is
* the case if the size of a way (# of sets * line size) does
* not exceed PAGE_SIZE.
*/
u32 waysize = icache_get_numsets() * icache_get_linesize();
if (l1ip != ICACHE_POLICY_VIPT || waysize > PAGE_SIZE)
set_bit(ICACHEF_ALIASING, &__icache_flags);
}
if (l1ip == ICACHE_POLICY_AIVIVT)
set_bit(ICACHEF_AIVIVT, &__icache_flags);
pr_info("Detected %s I-cache on CPU%d\n", icache_policy_str[l1ip], cpu);
}
static void __cpuinfo_store_cpu(struct cpuinfo_arm64 *info)
{
info->reg_cntfrq = arch_timer_get_cntfrq();
info->reg_ctr = read_cpuid_cachetype();
info->reg_dczid = read_cpuid(DCZID_EL0);
info->reg_midr = read_cpuid_id();
info->reg_id_aa64dfr0 = read_cpuid(ID_AA64DFR0_EL1);
info->reg_id_aa64dfr1 = read_cpuid(ID_AA64DFR1_EL1);
info->reg_id_aa64isar0 = read_cpuid(ID_AA64ISAR0_EL1);
info->reg_id_aa64isar1 = read_cpuid(ID_AA64ISAR1_EL1);
info->reg_id_aa64mmfr0 = read_cpuid(ID_AA64MMFR0_EL1);
info->reg_id_aa64mmfr1 = read_cpuid(ID_AA64MMFR1_EL1);
info->reg_id_aa64pfr0 = read_cpuid(ID_AA64PFR0_EL1);
info->reg_id_aa64pfr1 = read_cpuid(ID_AA64PFR1_EL1);
info->reg_id_dfr0 = read_cpuid(ID_DFR0_EL1);
info->reg_id_isar0 = read_cpuid(ID_ISAR0_EL1);
info->reg_id_isar1 = read_cpuid(ID_ISAR1_EL1);
info->reg_id_isar2 = read_cpuid(ID_ISAR2_EL1);
info->reg_id_isar3 = read_cpuid(ID_ISAR3_EL1);
info->reg_id_isar4 = read_cpuid(ID_ISAR4_EL1);
info->reg_id_isar5 = read_cpuid(ID_ISAR5_EL1);
info->reg_id_mmfr0 = read_cpuid(ID_MMFR0_EL1);
info->reg_id_mmfr1 = read_cpuid(ID_MMFR1_EL1);
info->reg_id_mmfr2 = read_cpuid(ID_MMFR2_EL1);
info->reg_id_mmfr3 = read_cpuid(ID_MMFR3_EL1);
info->reg_id_pfr0 = read_cpuid(ID_PFR0_EL1);
info->reg_id_pfr1 = read_cpuid(ID_PFR1_EL1);
info->reg_mvfr0 = read_cpuid(MVFR0_EL1);
info->reg_mvfr1 = read_cpuid(MVFR1_EL1);
info->reg_mvfr2 = read_cpuid(MVFR2_EL1);
cpuinfo_detect_icache_policy(info);
check_local_cpu_errata();
}
void cpuinfo_store_cpu(void)
{
struct cpuinfo_arm64 *info = this_cpu_ptr(&cpu_data);
__cpuinfo_store_cpu(info);
update_cpu_features(smp_processor_id(), info, &boot_cpu_data);
}
void __init cpuinfo_store_boot_cpu(void)
{
struct cpuinfo_arm64 *info = &per_cpu(cpu_data, 0);
__cpuinfo_store_cpu(info);
boot_cpu_data = *info;
init_cpu_features(&boot_cpu_data);
}