1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * PowerNV setup code. 4 * 5 * Copyright 2011 IBM Corp. 6 */ 7 8 #undef DEBUG 9 10 #include <linux/cpu.h> 11 #include <linux/errno.h> 12 #include <linux/sched.h> 13 #include <linux/kernel.h> 14 #include <linux/tty.h> 15 #include <linux/reboot.h> 16 #include <linux/init.h> 17 #include <linux/console.h> 18 #include <linux/delay.h> 19 #include <linux/irq.h> 20 #include <linux/seq_buf.h> 21 #include <linux/seq_file.h> 22 #include <linux/of.h> 23 #include <linux/of_fdt.h> 24 #include <linux/interrupt.h> 25 #include <linux/bug.h> 26 #include <linux/pci.h> 27 #include <linux/cpufreq.h> 28 #include <linux/memblock.h> 29 30 #include <asm/machdep.h> 31 #include <asm/firmware.h> 32 #include <asm/xics.h> 33 #include <asm/xive.h> 34 #include <asm/opal.h> 35 #include <asm/kexec.h> 36 #include <asm/smp.h> 37 #include <asm/tm.h> 38 #include <asm/setup.h> 39 #include <asm/security_features.h> 40 41 #include "powernv.h" 42 43 44 static bool __init fw_feature_is(const char *state, const char *name, 45 struct device_node *fw_features) 46 { 47 struct device_node *np; 48 bool rc = false; 49 50 np = of_get_child_by_name(fw_features, name); 51 if (np) { 52 rc = of_property_read_bool(np, state); 53 of_node_put(np); 54 } 55 56 return rc; 57 } 58 59 static void __init init_fw_feat_flags(struct device_node *np) 60 { 61 if (fw_feature_is("enabled", "inst-spec-barrier-ori31,31,0", np)) 62 security_ftr_set(SEC_FTR_SPEC_BAR_ORI31); 63 64 if (fw_feature_is("enabled", "fw-bcctrl-serialized", np)) 65 security_ftr_set(SEC_FTR_BCCTRL_SERIALISED); 66 67 if (fw_feature_is("enabled", "inst-l1d-flush-ori30,30,0", np)) 68 security_ftr_set(SEC_FTR_L1D_FLUSH_ORI30); 69 70 if (fw_feature_is("enabled", "inst-l1d-flush-trig2", np)) 71 security_ftr_set(SEC_FTR_L1D_FLUSH_TRIG2); 72 73 if (fw_feature_is("enabled", "fw-l1d-thread-split", np)) 74 security_ftr_set(SEC_FTR_L1D_THREAD_PRIV); 75 76 if (fw_feature_is("enabled", "fw-count-cache-disabled", np)) 77 security_ftr_set(SEC_FTR_COUNT_CACHE_DISABLED); 78 79 if (fw_feature_is("enabled", "fw-count-cache-flush-bcctr2,0,0", np)) 80 security_ftr_set(SEC_FTR_BCCTR_FLUSH_ASSIST); 81 82 if (fw_feature_is("enabled", "needs-count-cache-flush-on-context-switch", np)) 83 security_ftr_set(SEC_FTR_FLUSH_COUNT_CACHE); 84 85 /* 86 * The features below are enabled by default, so we instead look to see 87 * if firmware has *disabled* them, and clear them if so. 88 */ 89 if (fw_feature_is("disabled", "speculation-policy-favor-security", np)) 90 security_ftr_clear(SEC_FTR_FAVOUR_SECURITY); 91 92 if (fw_feature_is("disabled", "needs-l1d-flush-msr-pr-0-to-1", np)) 93 security_ftr_clear(SEC_FTR_L1D_FLUSH_PR); 94 95 if (fw_feature_is("disabled", "needs-l1d-flush-msr-hv-1-to-0", np)) 96 security_ftr_clear(SEC_FTR_L1D_FLUSH_HV); 97 98 if (fw_feature_is("disabled", "needs-spec-barrier-for-bound-checks", np)) 99 security_ftr_clear(SEC_FTR_BNDS_CHK_SPEC_BAR); 100 101 if (fw_feature_is("enabled", "no-need-l1d-flush-msr-pr-1-to-0", np)) 102 security_ftr_clear(SEC_FTR_L1D_FLUSH_ENTRY); 103 104 if (fw_feature_is("enabled", "no-need-l1d-flush-kernel-on-user-access", np)) 105 security_ftr_clear(SEC_FTR_L1D_FLUSH_UACCESS); 106 107 if (fw_feature_is("enabled", "no-need-store-drain-on-priv-state-switch", np)) 108 security_ftr_clear(SEC_FTR_STF_BARRIER); 109 } 110 111 static void __init pnv_setup_security_mitigations(void) 112 { 113 struct device_node *np, *fw_features; 114 enum l1d_flush_type type; 115 bool enable; 116 117 /* Default to fallback in case fw-features are not available */ 118 type = L1D_FLUSH_FALLBACK; 119 120 np = of_find_node_by_name(NULL, "ibm,opal"); 121 fw_features = of_get_child_by_name(np, "fw-features"); 122 of_node_put(np); 123 124 if (fw_features) { 125 init_fw_feat_flags(fw_features); 126 of_node_put(fw_features); 127 128 if (security_ftr_enabled(SEC_FTR_L1D_FLUSH_TRIG2)) 129 type = L1D_FLUSH_MTTRIG; 130 131 if (security_ftr_enabled(SEC_FTR_L1D_FLUSH_ORI30)) 132 type = L1D_FLUSH_ORI; 133 } 134 135 /* 136 * The issues addressed by the entry and uaccess flush don't affect P7 137 * or P8, so on bare metal disable them explicitly in case firmware does 138 * not include the features to disable them. POWER9 and newer processors 139 * should have the appropriate firmware flags. 140 */ 141 if (pvr_version_is(PVR_POWER7) || pvr_version_is(PVR_POWER7p) || 142 pvr_version_is(PVR_POWER8E) || pvr_version_is(PVR_POWER8NVL) || 143 pvr_version_is(PVR_POWER8)) { 144 security_ftr_clear(SEC_FTR_L1D_FLUSH_ENTRY); 145 security_ftr_clear(SEC_FTR_L1D_FLUSH_UACCESS); 146 } 147 148 enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) && \ 149 (security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR) || \ 150 security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV)); 151 152 setup_rfi_flush(type, enable); 153 setup_count_cache_flush(); 154 155 enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) && 156 security_ftr_enabled(SEC_FTR_L1D_FLUSH_ENTRY); 157 setup_entry_flush(enable); 158 159 enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) && 160 security_ftr_enabled(SEC_FTR_L1D_FLUSH_UACCESS); 161 setup_uaccess_flush(enable); 162 163 setup_stf_barrier(); 164 } 165 166 static void __init pnv_check_guarded_cores(void) 167 { 168 struct device_node *dn; 169 int bad_count = 0; 170 171 for_each_node_by_type(dn, "cpu") { 172 if (of_property_match_string(dn, "status", "bad") >= 0) 173 bad_count++; 174 } 175 176 if (bad_count) { 177 printk(" _ _______________\n"); 178 pr_cont(" | | / \\\n"); 179 pr_cont(" | | | WARNING! |\n"); 180 pr_cont(" | | | |\n"); 181 pr_cont(" | | | It looks like |\n"); 182 pr_cont(" |_| | you have %*d |\n", 3, bad_count); 183 pr_cont(" _ | guarded cores |\n"); 184 pr_cont(" (_) \\_______________/\n"); 185 } 186 } 187 188 static void __init pnv_setup_arch(void) 189 { 190 set_arch_panic_timeout(10, ARCH_PANIC_TIMEOUT); 191 192 pnv_setup_security_mitigations(); 193 194 /* Initialize SMP */ 195 pnv_smp_init(); 196 197 /* Setup RTC and NVRAM callbacks */ 198 if (firmware_has_feature(FW_FEATURE_OPAL)) 199 opal_nvram_init(); 200 201 /* Enable NAP mode */ 202 powersave_nap = 1; 203 204 pnv_check_guarded_cores(); 205 206 /* XXX PMCS */ 207 208 pnv_rng_init(); 209 } 210 211 static void __init pnv_add_hw_description(void) 212 { 213 struct device_node *dn; 214 const char *s; 215 216 dn = of_find_node_by_path("/ibm,opal/firmware"); 217 if (!dn) 218 return; 219 220 if (of_property_read_string(dn, "version", &s) == 0 || 221 of_property_read_string(dn, "git-id", &s) == 0) 222 seq_buf_printf(&ppc_hw_desc, "opal:%s ", s); 223 224 if (of_property_read_string(dn, "mi-version", &s) == 0) 225 seq_buf_printf(&ppc_hw_desc, "mi:%s ", s); 226 227 of_node_put(dn); 228 } 229 230 static void __init pnv_init(void) 231 { 232 pnv_add_hw_description(); 233 234 /* 235 * Initialize the LPC bus now so that legacy serial 236 * ports can be found on it 237 */ 238 opal_lpc_init(); 239 240 #ifdef CONFIG_HVC_OPAL 241 if (firmware_has_feature(FW_FEATURE_OPAL)) 242 hvc_opal_init_early(); 243 else 244 #endif 245 add_preferred_console("hvc", 0, NULL); 246 247 #ifdef CONFIG_PPC_64S_HASH_MMU 248 if (!radix_enabled()) { 249 size_t size = sizeof(struct slb_entry) * mmu_slb_size; 250 int i; 251 252 /* Allocate per cpu area to save old slb contents during MCE */ 253 for_each_possible_cpu(i) { 254 paca_ptrs[i]->mce_faulty_slbs = 255 memblock_alloc_node(size, 256 __alignof__(struct slb_entry), 257 cpu_to_node(i)); 258 } 259 } 260 #endif 261 } 262 263 static void __init pnv_init_IRQ(void) 264 { 265 /* Try using a XIVE if available, otherwise use a XICS */ 266 if (!xive_native_init()) 267 xics_init(); 268 269 WARN_ON(!ppc_md.get_irq); 270 } 271 272 static void pnv_show_cpuinfo(struct seq_file *m) 273 { 274 struct device_node *root; 275 const char *model = ""; 276 277 root = of_find_node_by_path("/"); 278 if (root) 279 model = of_get_property(root, "model", NULL); 280 seq_printf(m, "machine\t\t: PowerNV %s\n", model); 281 if (firmware_has_feature(FW_FEATURE_OPAL)) 282 seq_printf(m, "firmware\t: OPAL\n"); 283 else 284 seq_printf(m, "firmware\t: BML\n"); 285 of_node_put(root); 286 if (radix_enabled()) 287 seq_printf(m, "MMU\t\t: Radix\n"); 288 else 289 seq_printf(m, "MMU\t\t: Hash\n"); 290 } 291 292 static void pnv_prepare_going_down(void) 293 { 294 /* 295 * Disable all notifiers from OPAL, we can't 296 * service interrupts anymore anyway 297 */ 298 opal_event_shutdown(); 299 300 /* Print flash update message if one is scheduled. */ 301 opal_flash_update_print_message(); 302 303 smp_send_stop(); 304 305 hard_irq_disable(); 306 } 307 308 static void __noreturn pnv_restart(char *cmd) 309 { 310 long rc; 311 312 pnv_prepare_going_down(); 313 314 do { 315 if (!cmd || !strlen(cmd)) 316 rc = opal_cec_reboot(); 317 else if (strcmp(cmd, "full") == 0) 318 rc = opal_cec_reboot2(OPAL_REBOOT_FULL_IPL, NULL); 319 else if (strcmp(cmd, "mpipl") == 0) 320 rc = opal_cec_reboot2(OPAL_REBOOT_MPIPL, NULL); 321 else if (strcmp(cmd, "error") == 0) 322 rc = opal_cec_reboot2(OPAL_REBOOT_PLATFORM_ERROR, NULL); 323 else if (strcmp(cmd, "fast") == 0) 324 rc = opal_cec_reboot2(OPAL_REBOOT_FAST, NULL); 325 else 326 rc = OPAL_UNSUPPORTED; 327 328 if (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) { 329 /* Opal is busy wait for some time and retry */ 330 opal_poll_events(NULL); 331 mdelay(10); 332 333 } else if (cmd && rc) { 334 /* Unknown error while issuing reboot */ 335 if (rc == OPAL_UNSUPPORTED) 336 pr_err("Unsupported '%s' reboot.\n", cmd); 337 else 338 pr_err("Unable to issue '%s' reboot. Err=%ld\n", 339 cmd, rc); 340 pr_info("Forcing a cec-reboot\n"); 341 cmd = NULL; 342 rc = OPAL_BUSY; 343 344 } else if (rc != OPAL_SUCCESS) { 345 /* Unknown error while issuing cec-reboot */ 346 pr_err("Unable to reboot. Err=%ld\n", rc); 347 } 348 349 } while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT); 350 351 for (;;) 352 opal_poll_events(NULL); 353 } 354 355 static void __noreturn pnv_power_off(void) 356 { 357 long rc = OPAL_BUSY; 358 359 pnv_prepare_going_down(); 360 361 while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) { 362 rc = opal_cec_power_down(0); 363 if (rc == OPAL_BUSY_EVENT) 364 opal_poll_events(NULL); 365 else 366 mdelay(10); 367 } 368 for (;;) 369 opal_poll_events(NULL); 370 } 371 372 static void __noreturn pnv_halt(void) 373 { 374 pnv_power_off(); 375 } 376 377 static void pnv_progress(char *s, unsigned short hex) 378 { 379 } 380 381 static void pnv_shutdown(void) 382 { 383 /* Let the PCI code clear up IODA tables */ 384 pnv_pci_shutdown(); 385 386 /* 387 * Stop OPAL activity: Unregister all OPAL interrupts so they 388 * don't fire up while we kexec and make sure all potentially 389 * DMA'ing ops are complete (such as dump retrieval). 390 */ 391 opal_shutdown(); 392 } 393 394 #ifdef CONFIG_KEXEC_CORE 395 static void pnv_kexec_wait_secondaries_down(void) 396 { 397 int my_cpu, i, notified = -1; 398 399 my_cpu = get_cpu(); 400 401 for_each_online_cpu(i) { 402 uint8_t status; 403 int64_t rc, timeout = 1000; 404 405 if (i == my_cpu) 406 continue; 407 408 for (;;) { 409 rc = opal_query_cpu_status(get_hard_smp_processor_id(i), 410 &status); 411 if (rc != OPAL_SUCCESS || status != OPAL_THREAD_STARTED) 412 break; 413 barrier(); 414 if (i != notified) { 415 printk(KERN_INFO "kexec: waiting for cpu %d " 416 "(physical %d) to enter OPAL\n", 417 i, paca_ptrs[i]->hw_cpu_id); 418 notified = i; 419 } 420 421 /* 422 * On crash secondaries might be unreachable or hung, 423 * so timeout if we've waited too long 424 * */ 425 mdelay(1); 426 if (timeout-- == 0) { 427 printk(KERN_ERR "kexec: timed out waiting for " 428 "cpu %d (physical %d) to enter OPAL\n", 429 i, paca_ptrs[i]->hw_cpu_id); 430 break; 431 } 432 } 433 } 434 } 435 436 static void pnv_kexec_cpu_down(int crash_shutdown, int secondary) 437 { 438 u64 reinit_flags; 439 440 if (xive_enabled()) 441 xive_teardown_cpu(); 442 else 443 xics_kexec_teardown_cpu(secondary); 444 445 /* On OPAL, we return all CPUs to firmware */ 446 if (!firmware_has_feature(FW_FEATURE_OPAL)) 447 return; 448 449 if (secondary) { 450 /* Return secondary CPUs to firmware on OPAL v3 */ 451 mb(); 452 get_paca()->kexec_state = KEXEC_STATE_REAL_MODE; 453 mb(); 454 455 /* Return the CPU to OPAL */ 456 opal_return_cpu(); 457 } else { 458 /* Primary waits for the secondaries to have reached OPAL */ 459 pnv_kexec_wait_secondaries_down(); 460 461 /* Switch XIVE back to emulation mode */ 462 if (xive_enabled()) 463 xive_shutdown(); 464 465 /* 466 * We might be running as little-endian - now that interrupts 467 * are disabled, reset the HILE bit to big-endian so we don't 468 * take interrupts in the wrong endian later 469 * 470 * We reinit to enable both radix and hash on P9 to ensure 471 * the mode used by the next kernel is always supported. 472 */ 473 reinit_flags = OPAL_REINIT_CPUS_HILE_BE; 474 if (cpu_has_feature(CPU_FTR_ARCH_300)) 475 reinit_flags |= OPAL_REINIT_CPUS_MMU_RADIX | 476 OPAL_REINIT_CPUS_MMU_HASH; 477 opal_reinit_cpus(reinit_flags); 478 } 479 } 480 #endif /* CONFIG_KEXEC_CORE */ 481 482 #ifdef CONFIG_MEMORY_HOTPLUG 483 static unsigned long pnv_memory_block_size(void) 484 { 485 /* 486 * We map the kernel linear region with 1GB large pages on radix. For 487 * memory hot unplug to work our memory block size must be at least 488 * this size. 489 */ 490 if (radix_enabled()) 491 return radix_mem_block_size; 492 else 493 return 256UL * 1024 * 1024; 494 } 495 #endif 496 497 static void __init pnv_setup_machdep_opal(void) 498 { 499 ppc_md.get_boot_time = opal_get_boot_time; 500 ppc_md.restart = pnv_restart; 501 pm_power_off = pnv_power_off; 502 ppc_md.halt = pnv_halt; 503 /* ppc_md.system_reset_exception gets filled in by pnv_smp_init() */ 504 ppc_md.machine_check_exception = opal_machine_check; 505 ppc_md.mce_check_early_recovery = opal_mce_check_early_recovery; 506 if (opal_check_token(OPAL_HANDLE_HMI2)) 507 ppc_md.hmi_exception_early = opal_hmi_exception_early2; 508 else 509 ppc_md.hmi_exception_early = opal_hmi_exception_early; 510 ppc_md.handle_hmi_exception = opal_handle_hmi_exception; 511 } 512 513 static int __init pnv_probe(void) 514 { 515 if (!of_machine_is_compatible("ibm,powernv")) 516 return 0; 517 518 if (firmware_has_feature(FW_FEATURE_OPAL)) 519 pnv_setup_machdep_opal(); 520 521 pr_debug("PowerNV detected !\n"); 522 523 pnv_init(); 524 525 return 1; 526 } 527 528 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM 529 void __init pnv_tm_init(void) 530 { 531 if (!firmware_has_feature(FW_FEATURE_OPAL) || 532 !pvr_version_is(PVR_POWER9) || 533 early_cpu_has_feature(CPU_FTR_TM)) 534 return; 535 536 if (opal_reinit_cpus(OPAL_REINIT_CPUS_TM_SUSPEND_DISABLED) != OPAL_SUCCESS) 537 return; 538 539 pr_info("Enabling TM (Transactional Memory) with Suspend Disabled\n"); 540 cur_cpu_spec->cpu_features |= CPU_FTR_TM; 541 /* Make sure "normal" HTM is off (it should be) */ 542 cur_cpu_spec->cpu_user_features2 &= ~PPC_FEATURE2_HTM; 543 /* Turn on no suspend mode, and HTM no SC */ 544 cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_HTM_NO_SUSPEND | \ 545 PPC_FEATURE2_HTM_NOSC; 546 tm_suspend_disabled = true; 547 } 548 #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */ 549 550 /* 551 * Returns the cpu frequency for 'cpu' in Hz. This is used by 552 * /proc/cpuinfo 553 */ 554 static unsigned long pnv_get_proc_freq(unsigned int cpu) 555 { 556 unsigned long ret_freq; 557 558 ret_freq = cpufreq_get(cpu) * 1000ul; 559 560 /* 561 * If the backend cpufreq driver does not exist, 562 * then fallback to old way of reporting the clockrate. 563 */ 564 if (!ret_freq) 565 ret_freq = ppc_proc_freq; 566 return ret_freq; 567 } 568 569 static long pnv_machine_check_early(struct pt_regs *regs) 570 { 571 long handled = 0; 572 573 if (cur_cpu_spec && cur_cpu_spec->machine_check_early) 574 handled = cur_cpu_spec->machine_check_early(regs); 575 576 return handled; 577 } 578 579 define_machine(powernv) { 580 .name = "PowerNV", 581 .probe = pnv_probe, 582 .setup_arch = pnv_setup_arch, 583 .init_IRQ = pnv_init_IRQ, 584 .show_cpuinfo = pnv_show_cpuinfo, 585 .get_proc_freq = pnv_get_proc_freq, 586 .discover_phbs = pnv_pci_init, 587 .progress = pnv_progress, 588 .machine_shutdown = pnv_shutdown, 589 .power_save = NULL, 590 .calibrate_decr = generic_calibrate_decr, 591 .machine_check_early = pnv_machine_check_early, 592 #ifdef CONFIG_KEXEC_CORE 593 .kexec_cpu_down = pnv_kexec_cpu_down, 594 #endif 595 #ifdef CONFIG_MEMORY_HOTPLUG 596 .memory_block_size = pnv_memory_block_size, 597 #endif 598 }; 599