1 // SPDX-License-Identifier: GPL-2.0-or-later
5 * Copyright 2011 IBM Corp.
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_file.h>
22 #include <linux/of_fdt.h>
23 #include <linux/interrupt.h>
24 #include <linux/bug.h>
25 #include <linux/pci.h>
26 #include <linux/cpufreq.h>
27 #include <linux/memblock.h>
29 #include <asm/machdep.h>
30 #include <asm/firmware.h>
34 #include <asm/kexec.h>
37 #include <asm/setup.h>
38 #include <asm/security_features.h>
43 static bool __init fw_feature_is(const char *state, const char *name,
44 struct device_node *fw_features)
46 struct device_node *np;
49 np = of_get_child_by_name(fw_features, name);
51 rc = of_property_read_bool(np, state);
58 static void __init init_fw_feat_flags(struct device_node *np)
60 if (fw_feature_is("enabled", "inst-spec-barrier-ori31,31,0", np))
61 security_ftr_set(SEC_FTR_SPEC_BAR_ORI31);
63 if (fw_feature_is("enabled", "fw-bcctrl-serialized", np))
64 security_ftr_set(SEC_FTR_BCCTRL_SERIALISED);
66 if (fw_feature_is("enabled", "inst-l1d-flush-ori30,30,0", np))
67 security_ftr_set(SEC_FTR_L1D_FLUSH_ORI30);
69 if (fw_feature_is("enabled", "inst-l1d-flush-trig2", np))
70 security_ftr_set(SEC_FTR_L1D_FLUSH_TRIG2);
72 if (fw_feature_is("enabled", "fw-l1d-thread-split", np))
73 security_ftr_set(SEC_FTR_L1D_THREAD_PRIV);
75 if (fw_feature_is("enabled", "fw-count-cache-disabled", np))
76 security_ftr_set(SEC_FTR_COUNT_CACHE_DISABLED);
78 if (fw_feature_is("enabled", "fw-count-cache-flush-bcctr2,0,0", np))
79 security_ftr_set(SEC_FTR_BCCTR_FLUSH_ASSIST);
81 if (fw_feature_is("enabled", "needs-count-cache-flush-on-context-switch", np))
82 security_ftr_set(SEC_FTR_FLUSH_COUNT_CACHE);
85 * The features below are enabled by default, so we instead look to see
86 * if firmware has *disabled* them, and clear them if so.
88 if (fw_feature_is("disabled", "speculation-policy-favor-security", np))
89 security_ftr_clear(SEC_FTR_FAVOUR_SECURITY);
91 if (fw_feature_is("disabled", "needs-l1d-flush-msr-pr-0-to-1", np))
92 security_ftr_clear(SEC_FTR_L1D_FLUSH_PR);
94 if (fw_feature_is("disabled", "needs-l1d-flush-msr-hv-1-to-0", np))
95 security_ftr_clear(SEC_FTR_L1D_FLUSH_HV);
97 if (fw_feature_is("disabled", "needs-spec-barrier-for-bound-checks", np))
98 security_ftr_clear(SEC_FTR_BNDS_CHK_SPEC_BAR);
100 if (fw_feature_is("enabled", "no-need-l1d-flush-msr-pr-1-to-0", np))
101 security_ftr_clear(SEC_FTR_L1D_FLUSH_ENTRY);
103 if (fw_feature_is("enabled", "no-need-l1d-flush-kernel-on-user-access", np))
104 security_ftr_clear(SEC_FTR_L1D_FLUSH_UACCESS);
106 if (fw_feature_is("enabled", "no-need-store-drain-on-priv-state-switch", np))
107 security_ftr_clear(SEC_FTR_STF_BARRIER);
110 static void __init pnv_setup_security_mitigations(void)
112 struct device_node *np, *fw_features;
113 enum l1d_flush_type type;
116 /* Default to fallback in case fw-features are not available */
117 type = L1D_FLUSH_FALLBACK;
119 np = of_find_node_by_name(NULL, "ibm,opal");
120 fw_features = of_get_child_by_name(np, "fw-features");
124 init_fw_feat_flags(fw_features);
125 of_node_put(fw_features);
127 if (security_ftr_enabled(SEC_FTR_L1D_FLUSH_TRIG2))
128 type = L1D_FLUSH_MTTRIG;
130 if (security_ftr_enabled(SEC_FTR_L1D_FLUSH_ORI30))
131 type = L1D_FLUSH_ORI;
135 * The issues addressed by the entry and uaccess flush don't affect P7
136 * or P8, so on bare metal disable them explicitly in case firmware does
137 * not include the features to disable them. POWER9 and newer processors
138 * should have the appropriate firmware flags.
140 if (pvr_version_is(PVR_POWER7) || pvr_version_is(PVR_POWER7p) ||
141 pvr_version_is(PVR_POWER8E) || pvr_version_is(PVR_POWER8NVL) ||
142 pvr_version_is(PVR_POWER8)) {
143 security_ftr_clear(SEC_FTR_L1D_FLUSH_ENTRY);
144 security_ftr_clear(SEC_FTR_L1D_FLUSH_UACCESS);
147 enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) && \
148 (security_ftr_enabled(SEC_FTR_L1D_FLUSH_PR) || \
149 security_ftr_enabled(SEC_FTR_L1D_FLUSH_HV));
151 setup_rfi_flush(type, enable);
152 setup_count_cache_flush();
154 enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) &&
155 security_ftr_enabled(SEC_FTR_L1D_FLUSH_ENTRY);
156 setup_entry_flush(enable);
158 enable = security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) &&
159 security_ftr_enabled(SEC_FTR_L1D_FLUSH_UACCESS);
160 setup_uaccess_flush(enable);
165 static void __init pnv_check_guarded_cores(void)
167 struct device_node *dn;
170 for_each_node_by_type(dn, "cpu") {
171 if (of_property_match_string(dn, "status", "bad") >= 0)
176 printk(" _ _______________\n");
177 pr_cont(" | | / \\\n");
178 pr_cont(" | | | WARNING! |\n");
179 pr_cont(" | | | |\n");
180 pr_cont(" | | | It looks like |\n");
181 pr_cont(" |_| | you have %*d |\n", 3, bad_count);
182 pr_cont(" _ | guarded cores |\n");
183 pr_cont(" (_) \\_______________/\n");
187 static void __init pnv_setup_arch(void)
189 set_arch_panic_timeout(10, ARCH_PANIC_TIMEOUT);
191 pnv_setup_security_mitigations();
196 /* Setup RTC and NVRAM callbacks */
197 if (firmware_has_feature(FW_FEATURE_OPAL))
200 /* Enable NAP mode */
203 pnv_check_guarded_cores();
210 static void __init pnv_init(void)
213 * Initialize the LPC bus now so that legacy serial
214 * ports can be found on it
218 #ifdef CONFIG_HVC_OPAL
219 if (firmware_has_feature(FW_FEATURE_OPAL))
220 hvc_opal_init_early();
223 add_preferred_console("hvc", 0, NULL);
225 #ifdef CONFIG_PPC_64S_HASH_MMU
226 if (!radix_enabled()) {
227 size_t size = sizeof(struct slb_entry) * mmu_slb_size;
230 /* Allocate per cpu area to save old slb contents during MCE */
231 for_each_possible_cpu(i) {
232 paca_ptrs[i]->mce_faulty_slbs =
233 memblock_alloc_node(size,
234 __alignof__(struct slb_entry),
241 static void __init pnv_init_IRQ(void)
243 /* Try using a XIVE if available, otherwise use a XICS */
244 if (!xive_native_init())
247 WARN_ON(!ppc_md.get_irq);
250 static void pnv_show_cpuinfo(struct seq_file *m)
252 struct device_node *root;
253 const char *model = "";
255 root = of_find_node_by_path("/");
257 model = of_get_property(root, "model", NULL);
258 seq_printf(m, "machine\t\t: PowerNV %s\n", model);
259 if (firmware_has_feature(FW_FEATURE_OPAL))
260 seq_printf(m, "firmware\t: OPAL\n");
262 seq_printf(m, "firmware\t: BML\n");
265 seq_printf(m, "MMU\t\t: Radix\n");
267 seq_printf(m, "MMU\t\t: Hash\n");
270 static void pnv_prepare_going_down(void)
273 * Disable all notifiers from OPAL, we can't
274 * service interrupts anymore anyway
276 opal_event_shutdown();
278 /* Print flash update message if one is scheduled. */
279 opal_flash_update_print_message();
286 static void __noreturn pnv_restart(char *cmd)
290 pnv_prepare_going_down();
293 if (!cmd || !strlen(cmd))
294 rc = opal_cec_reboot();
295 else if (strcmp(cmd, "full") == 0)
296 rc = opal_cec_reboot2(OPAL_REBOOT_FULL_IPL, NULL);
297 else if (strcmp(cmd, "mpipl") == 0)
298 rc = opal_cec_reboot2(OPAL_REBOOT_MPIPL, NULL);
299 else if (strcmp(cmd, "error") == 0)
300 rc = opal_cec_reboot2(OPAL_REBOOT_PLATFORM_ERROR, NULL);
301 else if (strcmp(cmd, "fast") == 0)
302 rc = opal_cec_reboot2(OPAL_REBOOT_FAST, NULL);
304 rc = OPAL_UNSUPPORTED;
306 if (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
307 /* Opal is busy wait for some time and retry */
308 opal_poll_events(NULL);
311 } else if (cmd && rc) {
312 /* Unknown error while issuing reboot */
313 if (rc == OPAL_UNSUPPORTED)
314 pr_err("Unsupported '%s' reboot.\n", cmd);
316 pr_err("Unable to issue '%s' reboot. Err=%ld\n",
318 pr_info("Forcing a cec-reboot\n");
322 } else if (rc != OPAL_SUCCESS) {
323 /* Unknown error while issuing cec-reboot */
324 pr_err("Unable to reboot. Err=%ld\n", rc);
327 } while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT);
330 opal_poll_events(NULL);
333 static void __noreturn pnv_power_off(void)
337 pnv_prepare_going_down();
339 while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
340 rc = opal_cec_power_down(0);
341 if (rc == OPAL_BUSY_EVENT)
342 opal_poll_events(NULL);
347 opal_poll_events(NULL);
350 static void __noreturn pnv_halt(void)
355 static void pnv_progress(char *s, unsigned short hex)
359 static void pnv_shutdown(void)
361 /* Let the PCI code clear up IODA tables */
365 * Stop OPAL activity: Unregister all OPAL interrupts so they
366 * don't fire up while we kexec and make sure all potentially
367 * DMA'ing ops are complete (such as dump retrieval).
372 #ifdef CONFIG_KEXEC_CORE
373 static void pnv_kexec_wait_secondaries_down(void)
375 int my_cpu, i, notified = -1;
379 for_each_online_cpu(i) {
381 int64_t rc, timeout = 1000;
387 rc = opal_query_cpu_status(get_hard_smp_processor_id(i),
389 if (rc != OPAL_SUCCESS || status != OPAL_THREAD_STARTED)
393 printk(KERN_INFO "kexec: waiting for cpu %d "
394 "(physical %d) to enter OPAL\n",
395 i, paca_ptrs[i]->hw_cpu_id);
400 * On crash secondaries might be unreachable or hung,
401 * so timeout if we've waited too long
404 if (timeout-- == 0) {
405 printk(KERN_ERR "kexec: timed out waiting for "
406 "cpu %d (physical %d) to enter OPAL\n",
407 i, paca_ptrs[i]->hw_cpu_id);
414 static void pnv_kexec_cpu_down(int crash_shutdown, int secondary)
421 xics_kexec_teardown_cpu(secondary);
423 /* On OPAL, we return all CPUs to firmware */
424 if (!firmware_has_feature(FW_FEATURE_OPAL))
428 /* Return secondary CPUs to firmware on OPAL v3 */
430 get_paca()->kexec_state = KEXEC_STATE_REAL_MODE;
433 /* Return the CPU to OPAL */
436 /* Primary waits for the secondaries to have reached OPAL */
437 pnv_kexec_wait_secondaries_down();
439 /* Switch XIVE back to emulation mode */
444 * We might be running as little-endian - now that interrupts
445 * are disabled, reset the HILE bit to big-endian so we don't
446 * take interrupts in the wrong endian later
448 * We reinit to enable both radix and hash on P9 to ensure
449 * the mode used by the next kernel is always supported.
451 reinit_flags = OPAL_REINIT_CPUS_HILE_BE;
452 if (cpu_has_feature(CPU_FTR_ARCH_300))
453 reinit_flags |= OPAL_REINIT_CPUS_MMU_RADIX |
454 OPAL_REINIT_CPUS_MMU_HASH;
455 opal_reinit_cpus(reinit_flags);
458 #endif /* CONFIG_KEXEC_CORE */
460 #ifdef CONFIG_MEMORY_HOTPLUG
461 static unsigned long pnv_memory_block_size(void)
464 * We map the kernel linear region with 1GB large pages on radix. For
465 * memory hot unplug to work our memory block size must be at least
469 return radix_mem_block_size;
471 return 256UL * 1024 * 1024;
475 static void __init pnv_setup_machdep_opal(void)
477 ppc_md.get_boot_time = opal_get_boot_time;
478 ppc_md.restart = pnv_restart;
479 pm_power_off = pnv_power_off;
480 ppc_md.halt = pnv_halt;
481 /* ppc_md.system_reset_exception gets filled in by pnv_smp_init() */
482 ppc_md.machine_check_exception = opal_machine_check;
483 ppc_md.mce_check_early_recovery = opal_mce_check_early_recovery;
484 if (opal_check_token(OPAL_HANDLE_HMI2))
485 ppc_md.hmi_exception_early = opal_hmi_exception_early2;
487 ppc_md.hmi_exception_early = opal_hmi_exception_early;
488 ppc_md.handle_hmi_exception = opal_handle_hmi_exception;
491 static int __init pnv_probe(void)
493 if (!of_machine_is_compatible("ibm,powernv"))
496 if (firmware_has_feature(FW_FEATURE_OPAL))
497 pnv_setup_machdep_opal();
499 pr_debug("PowerNV detected !\n");
506 #ifdef CONFIG_PPC_TRANSACTIONAL_MEM
507 void __init pnv_tm_init(void)
509 if (!firmware_has_feature(FW_FEATURE_OPAL) ||
510 !pvr_version_is(PVR_POWER9) ||
511 early_cpu_has_feature(CPU_FTR_TM))
514 if (opal_reinit_cpus(OPAL_REINIT_CPUS_TM_SUSPEND_DISABLED) != OPAL_SUCCESS)
517 pr_info("Enabling TM (Transactional Memory) with Suspend Disabled\n");
518 cur_cpu_spec->cpu_features |= CPU_FTR_TM;
519 /* Make sure "normal" HTM is off (it should be) */
520 cur_cpu_spec->cpu_user_features2 &= ~PPC_FEATURE2_HTM;
521 /* Turn on no suspend mode, and HTM no SC */
522 cur_cpu_spec->cpu_user_features2 |= PPC_FEATURE2_HTM_NO_SUSPEND | \
523 PPC_FEATURE2_HTM_NOSC;
524 tm_suspend_disabled = true;
526 #endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
529 * Returns the cpu frequency for 'cpu' in Hz. This is used by
532 static unsigned long pnv_get_proc_freq(unsigned int cpu)
534 unsigned long ret_freq;
536 ret_freq = cpufreq_get(cpu) * 1000ul;
539 * If the backend cpufreq driver does not exist,
540 * then fallback to old way of reporting the clockrate.
543 ret_freq = ppc_proc_freq;
547 static long pnv_machine_check_early(struct pt_regs *regs)
551 if (cur_cpu_spec && cur_cpu_spec->machine_check_early)
552 handled = cur_cpu_spec->machine_check_early(regs);
557 define_machine(powernv) {
560 .setup_arch = pnv_setup_arch,
561 .init_IRQ = pnv_init_IRQ,
562 .show_cpuinfo = pnv_show_cpuinfo,
563 .get_proc_freq = pnv_get_proc_freq,
564 .discover_phbs = pnv_pci_init,
565 .progress = pnv_progress,
566 .machine_shutdown = pnv_shutdown,
568 .calibrate_decr = generic_calibrate_decr,
569 .machine_check_early = pnv_machine_check_early,
570 #ifdef CONFIG_KEXEC_CORE
571 .kexec_cpu_down = pnv_kexec_cpu_down,
573 #ifdef CONFIG_MEMORY_HOTPLUG
574 .memory_block_size = pnv_memory_block_size,