1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2012 Regents of the University of California 4 */ 5 6 #include <linux/acpi.h> 7 #include <linux/cpu.h> 8 #include <linux/ctype.h> 9 #include <linux/init.h> 10 #include <linux/seq_file.h> 11 #include <linux/of.h> 12 #include <asm/acpi.h> 13 #include <asm/cpufeature.h> 14 #include <asm/csr.h> 15 #include <asm/hwcap.h> 16 #include <asm/sbi.h> 17 #include <asm/smp.h> 18 #include <asm/pgtable.h> 19 20 bool arch_match_cpu_phys_id(int cpu, u64 phys_id) 21 { 22 return phys_id == cpuid_to_hartid_map(cpu); 23 } 24 25 /* 26 * Returns the hart ID of the given device tree node, or -ENODEV if the node 27 * isn't an enabled and valid RISC-V hart node. 28 */ 29 int riscv_of_processor_hartid(struct device_node *node, unsigned long *hart) 30 { 31 int cpu; 32 33 *hart = (unsigned long)of_get_cpu_hwid(node, 0); 34 if (*hart == ~0UL) { 35 pr_warn("Found CPU without hart ID\n"); 36 return -ENODEV; 37 } 38 39 cpu = riscv_hartid_to_cpuid(*hart); 40 if (cpu < 0) 41 return cpu; 42 43 if (!cpu_possible(cpu)) 44 return -ENODEV; 45 46 return 0; 47 } 48 49 int __init riscv_early_of_processor_hartid(struct device_node *node, unsigned long *hart) 50 { 51 const char *isa; 52 53 if (!of_device_is_compatible(node, "riscv")) { 54 pr_warn("Found incompatible CPU\n"); 55 return -ENODEV; 56 } 57 58 *hart = (unsigned long)of_get_cpu_hwid(node, 0); 59 if (*hart == ~0UL) { 60 pr_warn("Found CPU without hart ID\n"); 61 return -ENODEV; 62 } 63 64 if (!of_device_is_available(node)) { 65 pr_info("CPU with hartid=%lu is not available\n", *hart); 66 return -ENODEV; 67 } 68 69 if (of_property_read_string(node, "riscv,isa-base", &isa)) 70 goto old_interface; 71 72 if (IS_ENABLED(CONFIG_32BIT) && strncasecmp(isa, "rv32i", 5)) { 73 pr_warn("CPU with hartid=%lu does not support rv32i", *hart); 74 return -ENODEV; 75 } 76 77 if (IS_ENABLED(CONFIG_64BIT) && strncasecmp(isa, "rv64i", 5)) { 78 pr_warn("CPU with hartid=%lu does not support rv64i", *hart); 79 return -ENODEV; 80 } 81 82 if (!of_property_present(node, "riscv,isa-extensions")) 83 return -ENODEV; 84 85 if (of_property_match_string(node, "riscv,isa-extensions", "i") < 0 || 86 of_property_match_string(node, "riscv,isa-extensions", "m") < 0 || 87 of_property_match_string(node, "riscv,isa-extensions", "a") < 0) { 88 pr_warn("CPU with hartid=%lu does not support ima", *hart); 89 return -ENODEV; 90 } 91 92 return 0; 93 94 old_interface: 95 if (!riscv_isa_fallback) { 96 pr_warn("CPU with hartid=%lu is invalid: this kernel does not parse \"riscv,isa\"", 97 *hart); 98 return -ENODEV; 99 } 100 101 if (of_property_read_string(node, "riscv,isa", &isa)) { 102 pr_warn("CPU with hartid=%lu has no \"riscv,isa-base\" or \"riscv,isa\" property\n", 103 *hart); 104 return -ENODEV; 105 } 106 107 if (IS_ENABLED(CONFIG_32BIT) && strncasecmp(isa, "rv32ima", 7)) { 108 pr_warn("CPU with hartid=%lu does not support rv32ima", *hart); 109 return -ENODEV; 110 } 111 112 if (IS_ENABLED(CONFIG_64BIT) && strncasecmp(isa, "rv64ima", 7)) { 113 pr_warn("CPU with hartid=%lu does not support rv64ima", *hart); 114 return -ENODEV; 115 } 116 117 return 0; 118 } 119 120 /* 121 * Find hart ID of the CPU DT node under which given DT node falls. 122 * 123 * To achieve this, we walk up the DT tree until we find an active 124 * RISC-V core (HART) node and extract the cpuid from it. 125 */ 126 int riscv_of_parent_hartid(struct device_node *node, unsigned long *hartid) 127 { 128 for (; node; node = node->parent) { 129 if (of_device_is_compatible(node, "riscv")) { 130 *hartid = (unsigned long)of_get_cpu_hwid(node, 0); 131 if (*hartid == ~0UL) { 132 pr_warn("Found CPU without hart ID\n"); 133 return -ENODEV; 134 } 135 return 0; 136 } 137 } 138 139 return -1; 140 } 141 142 DEFINE_PER_CPU(struct riscv_cpuinfo, riscv_cpuinfo); 143 144 unsigned long riscv_cached_mvendorid(unsigned int cpu_id) 145 { 146 struct riscv_cpuinfo *ci = per_cpu_ptr(&riscv_cpuinfo, cpu_id); 147 148 return ci->mvendorid; 149 } 150 EXPORT_SYMBOL(riscv_cached_mvendorid); 151 152 unsigned long riscv_cached_marchid(unsigned int cpu_id) 153 { 154 struct riscv_cpuinfo *ci = per_cpu_ptr(&riscv_cpuinfo, cpu_id); 155 156 return ci->marchid; 157 } 158 EXPORT_SYMBOL(riscv_cached_marchid); 159 160 unsigned long riscv_cached_mimpid(unsigned int cpu_id) 161 { 162 struct riscv_cpuinfo *ci = per_cpu_ptr(&riscv_cpuinfo, cpu_id); 163 164 return ci->mimpid; 165 } 166 EXPORT_SYMBOL(riscv_cached_mimpid); 167 168 static int riscv_cpuinfo_starting(unsigned int cpu) 169 { 170 struct riscv_cpuinfo *ci = this_cpu_ptr(&riscv_cpuinfo); 171 172 #if IS_ENABLED(CONFIG_RISCV_SBI) 173 ci->mvendorid = sbi_spec_is_0_1() ? 0 : sbi_get_mvendorid(); 174 ci->marchid = sbi_spec_is_0_1() ? 0 : sbi_get_marchid(); 175 ci->mimpid = sbi_spec_is_0_1() ? 0 : sbi_get_mimpid(); 176 #elif IS_ENABLED(CONFIG_RISCV_M_MODE) 177 ci->mvendorid = csr_read(CSR_MVENDORID); 178 ci->marchid = csr_read(CSR_MARCHID); 179 ci->mimpid = csr_read(CSR_MIMPID); 180 #else 181 ci->mvendorid = 0; 182 ci->marchid = 0; 183 ci->mimpid = 0; 184 #endif 185 186 return 0; 187 } 188 189 static int __init riscv_cpuinfo_init(void) 190 { 191 int ret; 192 193 ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "riscv/cpuinfo:starting", 194 riscv_cpuinfo_starting, NULL); 195 if (ret < 0) { 196 pr_err("cpuinfo: failed to register hotplug callbacks.\n"); 197 return ret; 198 } 199 200 return 0; 201 } 202 arch_initcall(riscv_cpuinfo_init); 203 204 #ifdef CONFIG_PROC_FS 205 206 static void print_isa(struct seq_file *f, const unsigned long *isa_bitmap) 207 { 208 209 if (IS_ENABLED(CONFIG_32BIT)) 210 seq_write(f, "rv32", 4); 211 else 212 seq_write(f, "rv64", 4); 213 214 for (int i = 0; i < riscv_isa_ext_count; i++) { 215 if (!__riscv_isa_extension_available(isa_bitmap, riscv_isa_ext[i].id)) 216 continue; 217 218 /* Only multi-letter extensions are split by underscores */ 219 if (strnlen(riscv_isa_ext[i].name, 2) != 1) 220 seq_puts(f, "_"); 221 222 seq_printf(f, "%s", riscv_isa_ext[i].name); 223 } 224 225 seq_puts(f, "\n"); 226 } 227 228 static void print_mmu(struct seq_file *f) 229 { 230 const char *sv_type; 231 232 #ifdef CONFIG_MMU 233 #if defined(CONFIG_32BIT) 234 sv_type = "sv32"; 235 #elif defined(CONFIG_64BIT) 236 if (pgtable_l5_enabled) 237 sv_type = "sv57"; 238 else if (pgtable_l4_enabled) 239 sv_type = "sv48"; 240 else 241 sv_type = "sv39"; 242 #endif 243 #else 244 sv_type = "none"; 245 #endif /* CONFIG_MMU */ 246 seq_printf(f, "mmu\t\t: %s\n", sv_type); 247 } 248 249 static void *c_start(struct seq_file *m, loff_t *pos) 250 { 251 if (*pos == nr_cpu_ids) 252 return NULL; 253 254 *pos = cpumask_next(*pos - 1, cpu_online_mask); 255 if ((*pos) < nr_cpu_ids) 256 return (void *)(uintptr_t)(1 + *pos); 257 return NULL; 258 } 259 260 static void *c_next(struct seq_file *m, void *v, loff_t *pos) 261 { 262 (*pos)++; 263 return c_start(m, pos); 264 } 265 266 static void c_stop(struct seq_file *m, void *v) 267 { 268 } 269 270 static int c_show(struct seq_file *m, void *v) 271 { 272 unsigned long cpu_id = (unsigned long)v - 1; 273 struct riscv_cpuinfo *ci = per_cpu_ptr(&riscv_cpuinfo, cpu_id); 274 struct device_node *node; 275 const char *compat; 276 277 seq_printf(m, "processor\t: %lu\n", cpu_id); 278 seq_printf(m, "hart\t\t: %lu\n", cpuid_to_hartid_map(cpu_id)); 279 280 /* 281 * For historical raisins, the isa: line is limited to the lowest common 282 * denominator of extensions supported across all harts. A true list of 283 * extensions supported on this hart is printed later in the hart isa: 284 * line. 285 */ 286 seq_puts(m, "isa\t\t: "); 287 print_isa(m, NULL); 288 print_mmu(m); 289 290 if (acpi_disabled) { 291 node = of_get_cpu_node(cpu_id, NULL); 292 293 if (!of_property_read_string(node, "compatible", &compat) && 294 strcmp(compat, "riscv")) 295 seq_printf(m, "uarch\t\t: %s\n", compat); 296 297 of_node_put(node); 298 } 299 300 seq_printf(m, "mvendorid\t: 0x%lx\n", ci->mvendorid); 301 seq_printf(m, "marchid\t\t: 0x%lx\n", ci->marchid); 302 seq_printf(m, "mimpid\t\t: 0x%lx\n", ci->mimpid); 303 304 /* 305 * Print the ISA extensions specific to this hart, which may show 306 * additional extensions not present across all harts. 307 */ 308 seq_puts(m, "hart isa\t: "); 309 print_isa(m, hart_isa[cpu_id].isa); 310 seq_puts(m, "\n"); 311 312 return 0; 313 } 314 315 const struct seq_operations cpuinfo_op = { 316 .start = c_start, 317 .next = c_next, 318 .stop = c_stop, 319 .show = c_show 320 }; 321 322 #endif /* CONFIG_PROC_FS */ 323