1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * Copyright (C) 2001 Ben. Herrenschmidt (benh@kernel.crashing.org) |
4 | * |
5 | * Modifications for ppc64: |
6 | * Copyright (C) 2003 Dave Engebretsen <engebret@us.ibm.com> |
7 | */ |
8 | |
9 | #include <linux/string.h> |
10 | #include <linux/sched.h> |
11 | #include <linux/threads.h> |
12 | #include <linux/init.h> |
13 | #include <linux/export.h> |
14 | #include <linux/jump_label.h> |
15 | #include <linux/of.h> |
16 | |
17 | #include <asm/cputable.h> |
18 | #include <asm/mce.h> |
19 | #include <asm/mmu.h> |
20 | #include <asm/setup.h> |
21 | #include <asm/cpu_setup.h> |
22 | |
23 | static struct cpu_spec the_cpu_spec __ro_after_init; |
24 | |
25 | struct cpu_spec *cur_cpu_spec __ro_after_init = NULL; |
26 | EXPORT_SYMBOL(cur_cpu_spec); |
27 | |
28 | /* The platform string corresponding to the real PVR */ |
29 | const char *powerpc_base_platform; |
30 | |
31 | #include "cpu_specs.h" |
32 | |
33 | void __init set_cur_cpu_spec(struct cpu_spec *s) |
34 | { |
35 | struct cpu_spec *t = &the_cpu_spec; |
36 | |
37 | t = PTRRELOC(t); |
38 | /* |
39 | * use memcpy() instead of *t = *s so that GCC replaces it |
40 | * by __memcpy() when KASAN is active |
41 | */ |
42 | memcpy(t, s, sizeof(*t)); |
43 | |
44 | *PTRRELOC(&cur_cpu_spec) = &the_cpu_spec; |
45 | } |
46 | |
47 | static struct cpu_spec * __init setup_cpu_spec(unsigned long offset, |
48 | struct cpu_spec *s) |
49 | { |
50 | struct cpu_spec *t = &the_cpu_spec; |
51 | struct cpu_spec old; |
52 | |
53 | t = PTRRELOC(t); |
54 | old = *t; |
55 | |
56 | /* |
57 | * Copy everything, then do fixups. Use memcpy() instead of *t = *s |
58 | * so that GCC replaces it by __memcpy() when KASAN is active |
59 | */ |
60 | memcpy(t, s, sizeof(*t)); |
61 | |
62 | /* |
63 | * If we are overriding a previous value derived from the real |
64 | * PVR with a new value obtained using a logical PVR value, |
65 | * don't modify the performance monitor fields. |
66 | */ |
67 | if (old.num_pmcs && !s->num_pmcs) { |
68 | t->num_pmcs = old.num_pmcs; |
69 | t->pmc_type = old.pmc_type; |
70 | |
71 | /* |
72 | * Let's ensure that the |
73 | * fix for the PMAO bug is enabled on compatibility mode. |
74 | */ |
75 | t->cpu_features |= old.cpu_features & CPU_FTR_PMAO_BUG; |
76 | } |
77 | |
78 | /* Set kuap ON at startup, will be disabled later if cmdline has 'nosmap' */ |
79 | if (IS_ENABLED(CONFIG_PPC_KUAP) && IS_ENABLED(CONFIG_PPC32)) |
80 | t->mmu_features |= MMU_FTR_KUAP; |
81 | |
82 | *PTRRELOC(&cur_cpu_spec) = &the_cpu_spec; |
83 | |
84 | /* |
85 | * Set the base platform string once; assumes |
86 | * we're called with real pvr first. |
87 | */ |
88 | if (*PTRRELOC(&powerpc_base_platform) == NULL) |
89 | *PTRRELOC(&powerpc_base_platform) = t->platform; |
90 | |
91 | #if defined(CONFIG_PPC64) || defined(CONFIG_BOOKE) |
92 | /* ppc64 and booke expect identify_cpu to also call setup_cpu for |
93 | * that processor. I will consolidate that at a later time, for now, |
94 | * just use #ifdef. We also don't need to PTRRELOC the function |
95 | * pointer on ppc64 and booke as we are running at 0 in real mode |
96 | * on ppc64 and reloc_offset is always 0 on booke. |
97 | */ |
98 | if (t->cpu_setup) { |
99 | t->cpu_setup(offset, t); |
100 | } |
101 | #endif /* CONFIG_PPC64 || CONFIG_BOOKE */ |
102 | |
103 | return t; |
104 | } |
105 | |
106 | struct cpu_spec * __init identify_cpu(unsigned long offset, unsigned int pvr) |
107 | { |
108 | struct cpu_spec *s = cpu_specs; |
109 | int i; |
110 | |
111 | BUILD_BUG_ON(!ARRAY_SIZE(cpu_specs)); |
112 | |
113 | s = PTRRELOC(s); |
114 | |
115 | for (i = 0; i < ARRAY_SIZE(cpu_specs); i++,s++) { |
116 | if ((pvr & s->pvr_mask) == s->pvr_value) |
117 | return setup_cpu_spec(offset, s); |
118 | } |
119 | |
120 | BUG(); |
121 | |
122 | return NULL; |
123 | } |
124 | |
125 | /* |
126 | * Used by cpufeatures to get the name for CPUs with a PVR table. |
127 | * If they don't hae a PVR table, cpufeatures gets the name from |
128 | * cpu device-tree node. |
129 | */ |
130 | void __init identify_cpu_name(unsigned int pvr) |
131 | { |
132 | struct cpu_spec *s = cpu_specs; |
133 | struct cpu_spec *t = &the_cpu_spec; |
134 | int i; |
135 | |
136 | s = PTRRELOC(s); |
137 | t = PTRRELOC(t); |
138 | |
139 | for (i = 0; i < ARRAY_SIZE(cpu_specs); i++,s++) { |
140 | if ((pvr & s->pvr_mask) == s->pvr_value) { |
141 | t->cpu_name = s->cpu_name; |
142 | return; |
143 | } |
144 | } |
145 | } |
146 | |
147 | |
148 | #ifdef CONFIG_JUMP_LABEL_FEATURE_CHECKS |
149 | struct static_key_true cpu_feature_keys[NUM_CPU_FTR_KEYS] = { |
150 | [0 ... NUM_CPU_FTR_KEYS - 1] = STATIC_KEY_TRUE_INIT |
151 | }; |
152 | EXPORT_SYMBOL_GPL(cpu_feature_keys); |
153 | |
154 | void __init cpu_feature_keys_init(void) |
155 | { |
156 | int i; |
157 | |
158 | for (i = 0; i < NUM_CPU_FTR_KEYS; i++) { |
159 | unsigned long f = 1ul << i; |
160 | |
161 | if (!(cur_cpu_spec->cpu_features & f)) |
162 | static_branch_disable(&cpu_feature_keys[i]); |
163 | } |
164 | } |
165 | |
166 | struct static_key_true mmu_feature_keys[NUM_MMU_FTR_KEYS] = { |
167 | [0 ... NUM_MMU_FTR_KEYS - 1] = STATIC_KEY_TRUE_INIT |
168 | }; |
169 | EXPORT_SYMBOL(mmu_feature_keys); |
170 | |
171 | void __init mmu_feature_keys_init(void) |
172 | { |
173 | int i; |
174 | |
175 | for (i = 0; i < NUM_MMU_FTR_KEYS; i++) { |
176 | unsigned long f = 1ul << i; |
177 | |
178 | if (!(cur_cpu_spec->mmu_features & f)) |
179 | static_branch_disable(&mmu_feature_keys[i]); |
180 | } |
181 | } |
182 | #endif |
183 | |