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 __read_mostly; 24 25 struct cpu_spec* cur_cpu_spec __read_mostly = 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 *PTRRELOC(&cur_cpu_spec) = &the_cpu_spec; 79 80 /* 81 * Set the base platform string once; assumes 82 * we're called with real pvr first. 83 */ 84 if (*PTRRELOC(&powerpc_base_platform) == NULL) 85 *PTRRELOC(&powerpc_base_platform) = t->platform; 86 87 #if defined(CONFIG_PPC64) || defined(CONFIG_BOOKE) 88 /* ppc64 and booke expect identify_cpu to also call setup_cpu for 89 * that processor. I will consolidate that at a later time, for now, 90 * just use #ifdef. We also don't need to PTRRELOC the function 91 * pointer on ppc64 and booke as we are running at 0 in real mode 92 * on ppc64 and reloc_offset is always 0 on booke. 93 */ 94 if (t->cpu_setup) { 95 t->cpu_setup(offset, t); 96 } 97 #endif /* CONFIG_PPC64 || CONFIG_BOOKE */ 98 99 return t; 100 } 101 102 struct cpu_spec * __init identify_cpu(unsigned long offset, unsigned int pvr) 103 { 104 struct cpu_spec *s = cpu_specs; 105 int i; 106 107 BUILD_BUG_ON(!ARRAY_SIZE(cpu_specs)); 108 109 s = PTRRELOC(s); 110 111 for (i = 0; i < ARRAY_SIZE(cpu_specs); i++,s++) { 112 if ((pvr & s->pvr_mask) == s->pvr_value) 113 return setup_cpu_spec(offset, s); 114 } 115 116 BUG(); 117 118 return NULL; 119 } 120 121 /* 122 * Used by cpufeatures to get the name for CPUs with a PVR table. 123 * If they don't hae a PVR table, cpufeatures gets the name from 124 * cpu device-tree node. 125 */ 126 void __init identify_cpu_name(unsigned int pvr) 127 { 128 struct cpu_spec *s = cpu_specs; 129 struct cpu_spec *t = &the_cpu_spec; 130 int i; 131 132 s = PTRRELOC(s); 133 t = PTRRELOC(t); 134 135 for (i = 0; i < ARRAY_SIZE(cpu_specs); i++,s++) { 136 if ((pvr & s->pvr_mask) == s->pvr_value) { 137 t->cpu_name = s->cpu_name; 138 return; 139 } 140 } 141 } 142 143 144 #ifdef CONFIG_JUMP_LABEL_FEATURE_CHECKS 145 struct static_key_true cpu_feature_keys[NUM_CPU_FTR_KEYS] = { 146 [0 ... NUM_CPU_FTR_KEYS - 1] = STATIC_KEY_TRUE_INIT 147 }; 148 EXPORT_SYMBOL_GPL(cpu_feature_keys); 149 150 void __init cpu_feature_keys_init(void) 151 { 152 int i; 153 154 for (i = 0; i < NUM_CPU_FTR_KEYS; i++) { 155 unsigned long f = 1ul << i; 156 157 if (!(cur_cpu_spec->cpu_features & f)) 158 static_branch_disable(&cpu_feature_keys[i]); 159 } 160 } 161 162 struct static_key_true mmu_feature_keys[NUM_MMU_FTR_KEYS] = { 163 [0 ... NUM_MMU_FTR_KEYS - 1] = STATIC_KEY_TRUE_INIT 164 }; 165 EXPORT_SYMBOL(mmu_feature_keys); 166 167 void __init mmu_feature_keys_init(void) 168 { 169 int i; 170 171 for (i = 0; i < NUM_MMU_FTR_KEYS; i++) { 172 unsigned long f = 1ul << i; 173 174 if (!(cur_cpu_spec->mmu_features & f)) 175 static_branch_disable(&mmu_feature_keys[i]); 176 } 177 } 178 #endif 179