1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Hygon Processor Support for Linux 4 * 5 * Copyright (C) 2018 Chengdu Haiguang IC Design Co., Ltd. 6 * 7 * Author: Pu Wen <puwen@hygon.cn> 8 */ 9 #include <linux/io.h> 10 11 #include <asm/cpu.h> 12 #include <asm/smp.h> 13 #include <asm/numa.h> 14 #include <asm/cacheinfo.h> 15 #include <asm/spec-ctrl.h> 16 #include <asm/delay.h> 17 18 #include "cpu.h" 19 20 #define APICID_SOCKET_ID_BIT 6 21 22 /* 23 * nodes_per_socket: Stores the number of nodes per socket. 24 * Refer to CPUID Fn8000_001E_ECX Node Identifiers[10:8] 25 */ 26 static u32 nodes_per_socket = 1; 27 28 #ifdef CONFIG_NUMA 29 /* 30 * To workaround broken NUMA config. Read the comment in 31 * srat_detect_node(). 32 */ 33 static int nearby_node(int apicid) 34 { 35 int i, node; 36 37 for (i = apicid - 1; i >= 0; i--) { 38 node = __apicid_to_node[i]; 39 if (node != NUMA_NO_NODE && node_online(node)) 40 return node; 41 } 42 for (i = apicid + 1; i < MAX_LOCAL_APIC; i++) { 43 node = __apicid_to_node[i]; 44 if (node != NUMA_NO_NODE && node_online(node)) 45 return node; 46 } 47 return first_node(node_online_map); /* Shouldn't happen */ 48 } 49 #endif 50 51 static void hygon_get_topology_early(struct cpuinfo_x86 *c) 52 { 53 if (cpu_has(c, X86_FEATURE_TOPOEXT)) 54 smp_num_siblings = ((cpuid_ebx(0x8000001e) >> 8) & 0xff) + 1; 55 } 56 57 /* 58 * Fixup core topology information for 59 * (1) Hygon multi-node processors 60 * Assumption: Number of cores in each internal node is the same. 61 * (2) Hygon processors supporting compute units 62 */ 63 static void hygon_get_topology(struct cpuinfo_x86 *c) 64 { 65 int cpu = smp_processor_id(); 66 67 /* get information required for multi-node processors */ 68 if (boot_cpu_has(X86_FEATURE_TOPOEXT)) { 69 int err; 70 u32 eax, ebx, ecx, edx; 71 72 cpuid(0x8000001e, &eax, &ebx, &ecx, &edx); 73 74 c->cpu_die_id = ecx & 0xff; 75 76 c->cpu_core_id = ebx & 0xff; 77 78 if (smp_num_siblings > 1) 79 c->x86_max_cores /= smp_num_siblings; 80 81 /* 82 * In case leaf B is available, use it to derive 83 * topology information. 84 */ 85 err = detect_extended_topology(c); 86 if (!err) 87 c->x86_coreid_bits = get_count_order(c->x86_max_cores); 88 89 /* Socket ID is ApicId[6] for these processors. */ 90 c->phys_proc_id = c->apicid >> APICID_SOCKET_ID_BIT; 91 92 cacheinfo_hygon_init_llc_id(c, cpu); 93 } else if (cpu_has(c, X86_FEATURE_NODEID_MSR)) { 94 u64 value; 95 96 rdmsrl(MSR_FAM10H_NODE_ID, value); 97 c->cpu_die_id = value & 7; 98 99 per_cpu(cpu_llc_id, cpu) = c->cpu_die_id; 100 } else 101 return; 102 103 if (nodes_per_socket > 1) 104 set_cpu_cap(c, X86_FEATURE_AMD_DCM); 105 } 106 107 /* 108 * On Hygon setup the lower bits of the APIC id distinguish the cores. 109 * Assumes number of cores is a power of two. 110 */ 111 static void hygon_detect_cmp(struct cpuinfo_x86 *c) 112 { 113 unsigned int bits; 114 int cpu = smp_processor_id(); 115 116 bits = c->x86_coreid_bits; 117 /* Low order bits define the core id (index of core in socket) */ 118 c->cpu_core_id = c->initial_apicid & ((1 << bits)-1); 119 /* Convert the initial APIC ID into the socket ID */ 120 c->phys_proc_id = c->initial_apicid >> bits; 121 /* use socket ID also for last level cache */ 122 per_cpu(cpu_llc_id, cpu) = c->cpu_die_id = c->phys_proc_id; 123 } 124 125 static void srat_detect_node(struct cpuinfo_x86 *c) 126 { 127 #ifdef CONFIG_NUMA 128 int cpu = smp_processor_id(); 129 int node; 130 unsigned int apicid = c->apicid; 131 132 node = numa_cpu_node(cpu); 133 if (node == NUMA_NO_NODE) 134 node = per_cpu(cpu_llc_id, cpu); 135 136 /* 137 * On multi-fabric platform (e.g. Numascale NumaChip) a 138 * platform-specific handler needs to be called to fixup some 139 * IDs of the CPU. 140 */ 141 if (x86_cpuinit.fixup_cpu_id) 142 x86_cpuinit.fixup_cpu_id(c, node); 143 144 if (!node_online(node)) { 145 /* 146 * Two possibilities here: 147 * 148 * - The CPU is missing memory and no node was created. In 149 * that case try picking one from a nearby CPU. 150 * 151 * - The APIC IDs differ from the HyperTransport node IDs. 152 * Assume they are all increased by a constant offset, but 153 * in the same order as the HT nodeids. If that doesn't 154 * result in a usable node fall back to the path for the 155 * previous case. 156 * 157 * This workaround operates directly on the mapping between 158 * APIC ID and NUMA node, assuming certain relationship 159 * between APIC ID, HT node ID and NUMA topology. As going 160 * through CPU mapping may alter the outcome, directly 161 * access __apicid_to_node[]. 162 */ 163 int ht_nodeid = c->initial_apicid; 164 165 if (__apicid_to_node[ht_nodeid] != NUMA_NO_NODE) 166 node = __apicid_to_node[ht_nodeid]; 167 /* Pick a nearby node */ 168 if (!node_online(node)) 169 node = nearby_node(apicid); 170 } 171 numa_set_node(cpu, node); 172 #endif 173 } 174 175 static void early_init_hygon_mc(struct cpuinfo_x86 *c) 176 { 177 #ifdef CONFIG_SMP 178 unsigned int bits, ecx; 179 180 /* Multi core CPU? */ 181 if (c->extended_cpuid_level < 0x80000008) 182 return; 183 184 ecx = cpuid_ecx(0x80000008); 185 186 c->x86_max_cores = (ecx & 0xff) + 1; 187 188 /* CPU telling us the core id bits shift? */ 189 bits = (ecx >> 12) & 0xF; 190 191 /* Otherwise recompute */ 192 if (bits == 0) { 193 while ((1 << bits) < c->x86_max_cores) 194 bits++; 195 } 196 197 c->x86_coreid_bits = bits; 198 #endif 199 } 200 201 static void bsp_init_hygon(struct cpuinfo_x86 *c) 202 { 203 if (cpu_has(c, X86_FEATURE_CONSTANT_TSC)) { 204 u64 val; 205 206 rdmsrl(MSR_K7_HWCR, val); 207 if (!(val & BIT(24))) 208 pr_warn(FW_BUG "TSC doesn't count with P0 frequency!\n"); 209 } 210 211 if (cpu_has(c, X86_FEATURE_MWAITX)) 212 use_mwaitx_delay(); 213 214 if (boot_cpu_has(X86_FEATURE_TOPOEXT)) { 215 u32 ecx; 216 217 ecx = cpuid_ecx(0x8000001e); 218 nodes_per_socket = ((ecx >> 8) & 7) + 1; 219 } else if (boot_cpu_has(X86_FEATURE_NODEID_MSR)) { 220 u64 value; 221 222 rdmsrl(MSR_FAM10H_NODE_ID, value); 223 nodes_per_socket = ((value >> 3) & 7) + 1; 224 } 225 226 if (!boot_cpu_has(X86_FEATURE_AMD_SSBD) && 227 !boot_cpu_has(X86_FEATURE_VIRT_SSBD)) { 228 /* 229 * Try to cache the base value so further operations can 230 * avoid RMW. If that faults, do not enable SSBD. 231 */ 232 if (!rdmsrl_safe(MSR_AMD64_LS_CFG, &x86_amd_ls_cfg_base)) { 233 setup_force_cpu_cap(X86_FEATURE_LS_CFG_SSBD); 234 setup_force_cpu_cap(X86_FEATURE_SSBD); 235 x86_amd_ls_cfg_ssbd_mask = 1ULL << 10; 236 } 237 } 238 } 239 240 static void early_init_hygon(struct cpuinfo_x86 *c) 241 { 242 u32 dummy; 243 244 early_init_hygon_mc(c); 245 246 set_cpu_cap(c, X86_FEATURE_K8); 247 248 rdmsr_safe(MSR_AMD64_PATCH_LEVEL, &c->microcode, &dummy); 249 250 /* 251 * c->x86_power is 8000_0007 edx. Bit 8 is TSC runs at constant rate 252 * with P/T states and does not stop in deep C-states 253 */ 254 if (c->x86_power & (1 << 8)) { 255 set_cpu_cap(c, X86_FEATURE_CONSTANT_TSC); 256 set_cpu_cap(c, X86_FEATURE_NONSTOP_TSC); 257 } 258 259 /* Bit 12 of 8000_0007 edx is accumulated power mechanism. */ 260 if (c->x86_power & BIT(12)) 261 set_cpu_cap(c, X86_FEATURE_ACC_POWER); 262 263 #ifdef CONFIG_X86_64 264 set_cpu_cap(c, X86_FEATURE_SYSCALL32); 265 #endif 266 267 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_PCI) 268 /* 269 * ApicID can always be treated as an 8-bit value for Hygon APIC So, we 270 * can safely set X86_FEATURE_EXTD_APICID unconditionally. 271 */ 272 if (boot_cpu_has(X86_FEATURE_APIC)) 273 set_cpu_cap(c, X86_FEATURE_EXTD_APICID); 274 #endif 275 276 /* 277 * This is only needed to tell the kernel whether to use VMCALL 278 * and VMMCALL. VMMCALL is never executed except under virt, so 279 * we can set it unconditionally. 280 */ 281 set_cpu_cap(c, X86_FEATURE_VMMCALL); 282 283 hygon_get_topology_early(c); 284 } 285 286 static void init_hygon(struct cpuinfo_x86 *c) 287 { 288 early_init_hygon(c); 289 290 /* 291 * Bit 31 in normal CPUID used for nonstandard 3DNow ID; 292 * 3DNow is IDd by bit 31 in extended CPUID (1*32+31) anyway 293 */ 294 clear_cpu_cap(c, 0*32+31); 295 296 set_cpu_cap(c, X86_FEATURE_REP_GOOD); 297 298 /* get apicid instead of initial apic id from cpuid */ 299 c->apicid = hard_smp_processor_id(); 300 301 set_cpu_cap(c, X86_FEATURE_ZEN); 302 set_cpu_cap(c, X86_FEATURE_CPB); 303 304 cpu_detect_cache_sizes(c); 305 306 hygon_detect_cmp(c); 307 hygon_get_topology(c); 308 srat_detect_node(c); 309 310 init_hygon_cacheinfo(c); 311 312 if (cpu_has(c, X86_FEATURE_XMM2)) { 313 /* 314 * Use LFENCE for execution serialization. On families which 315 * don't have that MSR, LFENCE is already serializing. 316 * msr_set_bit() uses the safe accessors, too, even if the MSR 317 * is not present. 318 */ 319 msr_set_bit(MSR_F10H_DECFG, 320 MSR_F10H_DECFG_LFENCE_SERIALIZE_BIT); 321 322 /* A serializing LFENCE stops RDTSC speculation */ 323 set_cpu_cap(c, X86_FEATURE_LFENCE_RDTSC); 324 } 325 326 /* 327 * Hygon processors have APIC timer running in deep C states. 328 */ 329 set_cpu_cap(c, X86_FEATURE_ARAT); 330 331 /* Hygon CPUs don't reset SS attributes on SYSRET, Xen does. */ 332 if (!cpu_has(c, X86_FEATURE_XENPV)) 333 set_cpu_bug(c, X86_BUG_SYSRET_SS_ATTRS); 334 } 335 336 static void cpu_detect_tlb_hygon(struct cpuinfo_x86 *c) 337 { 338 u32 ebx, eax, ecx, edx; 339 u16 mask = 0xfff; 340 341 if (c->extended_cpuid_level < 0x80000006) 342 return; 343 344 cpuid(0x80000006, &eax, &ebx, &ecx, &edx); 345 346 tlb_lld_4k[ENTRIES] = (ebx >> 16) & mask; 347 tlb_lli_4k[ENTRIES] = ebx & mask; 348 349 /* Handle DTLB 2M and 4M sizes, fall back to L1 if L2 is disabled */ 350 if (!((eax >> 16) & mask)) 351 tlb_lld_2m[ENTRIES] = (cpuid_eax(0x80000005) >> 16) & 0xff; 352 else 353 tlb_lld_2m[ENTRIES] = (eax >> 16) & mask; 354 355 /* a 4M entry uses two 2M entries */ 356 tlb_lld_4m[ENTRIES] = tlb_lld_2m[ENTRIES] >> 1; 357 358 /* Handle ITLB 2M and 4M sizes, fall back to L1 if L2 is disabled */ 359 if (!(eax & mask)) { 360 cpuid(0x80000005, &eax, &ebx, &ecx, &edx); 361 tlb_lli_2m[ENTRIES] = eax & 0xff; 362 } else 363 tlb_lli_2m[ENTRIES] = eax & mask; 364 365 tlb_lli_4m[ENTRIES] = tlb_lli_2m[ENTRIES] >> 1; 366 } 367 368 static const struct cpu_dev hygon_cpu_dev = { 369 .c_vendor = "Hygon", 370 .c_ident = { "HygonGenuine" }, 371 .c_early_init = early_init_hygon, 372 .c_detect_tlb = cpu_detect_tlb_hygon, 373 .c_bsp_init = bsp_init_hygon, 374 .c_init = init_hygon, 375 .c_x86_vendor = X86_VENDOR_HYGON, 376 }; 377 378 cpu_dev_register(hygon_cpu_dev); 379