1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
|
/*
* Contains CPU specific errata definitions
*
* 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/>.
*/
#define pr_fmt(fmt) "alternative: " fmt
#include <linux/types.h>
#include <asm/cpu.h>
#include <asm/cputype.h>
#include <asm/cpufeature.h>
#define MIDR_CORTEX_A53 MIDR_CPU_PART(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A53)
/*
* 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)
{
u32 midr = read_cpuid_id();
if ((midr & CPU_MODEL_MASK) != entry->midr_model)
return false;
midr &= MIDR_REVISION_MASK | MIDR_VARIANT_MASK;
return (midr >= entry->midr_range_min && midr <= entry->midr_range_max);
}
#define MIDR_RANGE(model, min, max) \
.is_affected = is_affected_midr_range, \
.midr_model = model, \
.midr_range_min = min, \
.midr_range_max = max
struct arm64_cpu_capabilities arm64_errata[] = {
{
/* Cortex-A53 r0p[012] */
.desc = "ARM errata 826319, 827319, 824069",
.capability = ARM64_WORKAROUND_CLEAN_CACHE,
MIDR_RANGE(MIDR_CORTEX_A53, 0x00, 0x02),
},
{
}
};
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);
}
}
|