xref: /openbmc/linux/arch/arm64/kernel/cpuinfo.c (revision df857416)
1 /*
2  * Record and handle CPU attributes.
3  *
4  * Copyright (C) 2014 ARM Ltd.
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
16  */
17 #include <asm/arch_timer.h>
18 #include <asm/cachetype.h>
19 #include <asm/cpu.h>
20 #include <asm/cputype.h>
21 
22 #include <linux/init.h>
23 #include <linux/smp.h>
24 
25 /*
26  * In case the boot CPU is hotpluggable, we record its initial state and
27  * current state separately. Certain system registers may contain different
28  * values depending on configuration at or after reset.
29  */
30 DEFINE_PER_CPU(struct cpuinfo_arm64, cpu_data);
31 static struct cpuinfo_arm64 boot_cpu_data;
32 
33 static void __cpuinfo_store_cpu(struct cpuinfo_arm64 *info)
34 {
35 	info->reg_cntfrq = arch_timer_get_cntfrq();
36 	info->reg_ctr = read_cpuid_cachetype();
37 	info->reg_dczid = read_cpuid(DCZID_EL0);
38 	info->reg_midr = read_cpuid_id();
39 
40 	info->reg_id_aa64isar0 = read_cpuid(ID_AA64ISAR0_EL1);
41 	info->reg_id_aa64isar1 = read_cpuid(ID_AA64ISAR1_EL1);
42 	info->reg_id_aa64mmfr0 = read_cpuid(ID_AA64MMFR0_EL1);
43 	info->reg_id_aa64mmfr1 = read_cpuid(ID_AA64MMFR1_EL1);
44 	info->reg_id_aa64pfr0 = read_cpuid(ID_AA64PFR0_EL1);
45 	info->reg_id_aa64pfr1 = read_cpuid(ID_AA64PFR1_EL1);
46 
47 	info->reg_id_isar0 = read_cpuid(ID_ISAR0_EL1);
48 	info->reg_id_isar1 = read_cpuid(ID_ISAR1_EL1);
49 	info->reg_id_isar2 = read_cpuid(ID_ISAR2_EL1);
50 	info->reg_id_isar3 = read_cpuid(ID_ISAR3_EL1);
51 	info->reg_id_isar4 = read_cpuid(ID_ISAR4_EL1);
52 	info->reg_id_isar5 = read_cpuid(ID_ISAR5_EL1);
53 	info->reg_id_mmfr0 = read_cpuid(ID_MMFR0_EL1);
54 	info->reg_id_mmfr1 = read_cpuid(ID_MMFR1_EL1);
55 	info->reg_id_mmfr2 = read_cpuid(ID_MMFR2_EL1);
56 	info->reg_id_mmfr3 = read_cpuid(ID_MMFR3_EL1);
57 	info->reg_id_pfr0 = read_cpuid(ID_PFR0_EL1);
58 	info->reg_id_pfr1 = read_cpuid(ID_PFR1_EL1);
59 }
60 
61 void cpuinfo_store_cpu(void)
62 {
63 	struct cpuinfo_arm64 *info = this_cpu_ptr(&cpu_data);
64 	__cpuinfo_store_cpu(info);
65 }
66 
67 void __init cpuinfo_store_boot_cpu(void)
68 {
69 	struct cpuinfo_arm64 *info = &per_cpu(cpu_data, 0);
70 	__cpuinfo_store_cpu(info);
71 
72 	boot_cpu_data = *info;
73 }
74