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1/*
2 * CPU Microcode Update Driver for Linux
3 *
4 * Copyright (C) 2000-2006 Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
5 * 2006 Shaohua Li <shaohua.li@intel.com>
6 * 2013-2015 Borislav Petkov <bp@alien8.de>
7 *
8 * X86 CPU microcode early update for Linux:
9 *
10 * Copyright (C) 2012 Fenghua Yu <fenghua.yu@intel.com>
11 * H Peter Anvin" <hpa@zytor.com>
12 * (C) 2015 Borislav Petkov <bp@alien8.de>
13 *
14 * This driver allows to upgrade microcode on x86 processors.
15 *
16 * This program is free software; you can redistribute it and/or
17 * modify it under the terms of the GNU General Public License
18 * as published by the Free Software Foundation; either version
19 * 2 of the License, or (at your option) any later version.
20 */
21
22#define pr_fmt(fmt) "microcode: " fmt
23
24#include <linux/platform_device.h>
25#include <linux/syscore_ops.h>
26#include <linux/miscdevice.h>
27#include <linux/capability.h>
28#include <linux/firmware.h>
29#include <linux/kernel.h>
30#include <linux/mutex.h>
31#include <linux/cpu.h>
32#include <linux/fs.h>
33#include <linux/mm.h>
34
35#include <asm/microcode_intel.h>
36#include <asm/cpu_device_id.h>
37#include <asm/microcode_amd.h>
38#include <asm/perf_event.h>
39#include <asm/microcode.h>
40#include <asm/processor.h>
41#include <asm/cmdline.h>
42
43#define MICROCODE_VERSION "2.01"
44
45static struct microcode_ops *microcode_ops;
46static bool dis_ucode_ldr;
47
48/*
49 * Synchronization.
50 *
51 * All non cpu-hotplug-callback call sites use:
52 *
53 * - microcode_mutex to synchronize with each other;
54 * - get/put_online_cpus() to synchronize with
55 * the cpu-hotplug-callback call sites.
56 *
57 * We guarantee that only a single cpu is being
58 * updated at any particular moment of time.
59 */
60static DEFINE_MUTEX(microcode_mutex);
61
62struct ucode_cpu_info ucode_cpu_info[NR_CPUS];
63EXPORT_SYMBOL_GPL(ucode_cpu_info);
64
65/*
66 * Operations that are run on a target cpu:
67 */
68
69struct cpu_info_ctx {
70 struct cpu_signature *cpu_sig;
71 int err;
72};
73
74static bool __init check_loader_disabled_bsp(void)
75{
76 static const char *__dis_opt_str = "dis_ucode_ldr";
77
78#ifdef CONFIG_X86_32
79 const char *cmdline = (const char *)__pa_nodebug(boot_command_line);
80 const char *option = (const char *)__pa_nodebug(__dis_opt_str);
81 bool *res = (bool *)__pa_nodebug(&dis_ucode_ldr);
82
83#else /* CONFIG_X86_64 */
84 const char *cmdline = boot_command_line;
85 const char *option = __dis_opt_str;
86 bool *res = &dis_ucode_ldr;
87#endif
88
89 if (cmdline_find_option_bool(cmdline, option))
90 *res = true;
91
92 return *res;
93}
94
95extern struct builtin_fw __start_builtin_fw[];
96extern struct builtin_fw __end_builtin_fw[];
97
98bool get_builtin_firmware(struct cpio_data *cd, const char *name)
99{
100#ifdef CONFIG_FW_LOADER
101 struct builtin_fw *b_fw;
102
103 for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
104 if (!strcmp(name, b_fw->name)) {
105 cd->size = b_fw->size;
106 cd->data = b_fw->data;
107 return true;
108 }
109 }
110#endif
111 return false;
112}
113
114void __init load_ucode_bsp(void)
115{
116 int vendor;
117 unsigned int family;
118
119 if (check_loader_disabled_bsp())
120 return;
121
122 if (!have_cpuid_p())
123 return;
124
125 vendor = x86_cpuid_vendor();
126 family = x86_cpuid_family();
127
128 switch (vendor) {
129 case X86_VENDOR_INTEL:
130 if (family >= 6)
131 load_ucode_intel_bsp();
132 break;
133 case X86_VENDOR_AMD:
134 if (family >= 0x10)
135 load_ucode_amd_bsp(family);
136 break;
137 default:
138 break;
139 }
140}
141
142static bool check_loader_disabled_ap(void)
143{
144#ifdef CONFIG_X86_32
145 return *((bool *)__pa_nodebug(&dis_ucode_ldr));
146#else
147 return dis_ucode_ldr;
148#endif
149}
150
151void load_ucode_ap(void)
152{
153 int vendor, family;
154
155 if (check_loader_disabled_ap())
156 return;
157
158 if (!have_cpuid_p())
159 return;
160
161 vendor = x86_cpuid_vendor();
162 family = x86_cpuid_family();
163
164 switch (vendor) {
165 case X86_VENDOR_INTEL:
166 if (family >= 6)
167 load_ucode_intel_ap();
168 break;
169 case X86_VENDOR_AMD:
170 if (family >= 0x10)
171 load_ucode_amd_ap();
172 break;
173 default:
174 break;
175 }
176}
177
178int __init save_microcode_in_initrd(void)
179{
180 struct cpuinfo_x86 *c = &boot_cpu_data;
181
182 switch (c->x86_vendor) {
183 case X86_VENDOR_INTEL:
184 if (c->x86 >= 6)
185 save_microcode_in_initrd_intel();
186 break;
187 case X86_VENDOR_AMD:
188 if (c->x86 >= 0x10)
189 save_microcode_in_initrd_amd();
190 break;
191 default:
192 break;
193 }
194
195 return 0;
196}
197
198void reload_early_microcode(void)
199{
200 int vendor, family;
201
202 vendor = x86_cpuid_vendor();
203 family = x86_cpuid_family();
204
205 switch (vendor) {
206 case X86_VENDOR_INTEL:
207 if (family >= 6)
208 reload_ucode_intel();
209 break;
210 case X86_VENDOR_AMD:
211 if (family >= 0x10)
212 reload_ucode_amd();
213 break;
214 default:
215 break;
216 }
217}
218
219static void collect_cpu_info_local(void *arg)
220{
221 struct cpu_info_ctx *ctx = arg;
222
223 ctx->err = microcode_ops->collect_cpu_info(smp_processor_id(),
224 ctx->cpu_sig);
225}
226
227static int collect_cpu_info_on_target(int cpu, struct cpu_signature *cpu_sig)
228{
229 struct cpu_info_ctx ctx = { .cpu_sig = cpu_sig, .err = 0 };
230 int ret;
231
232 ret = smp_call_function_single(cpu, collect_cpu_info_local, &ctx, 1);
233 if (!ret)
234 ret = ctx.err;
235
236 return ret;
237}
238
239static int collect_cpu_info(int cpu)
240{
241 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
242 int ret;
243
244 memset(uci, 0, sizeof(*uci));
245
246 ret = collect_cpu_info_on_target(cpu, &uci->cpu_sig);
247 if (!ret)
248 uci->valid = 1;
249
250 return ret;
251}
252
253struct apply_microcode_ctx {
254 int err;
255};
256
257static void apply_microcode_local(void *arg)
258{
259 struct apply_microcode_ctx *ctx = arg;
260
261 ctx->err = microcode_ops->apply_microcode(smp_processor_id());
262}
263
264static int apply_microcode_on_target(int cpu)
265{
266 struct apply_microcode_ctx ctx = { .err = 0 };
267 int ret;
268
269 ret = smp_call_function_single(cpu, apply_microcode_local, &ctx, 1);
270 if (!ret)
271 ret = ctx.err;
272
273 return ret;
274}
275
276#ifdef CONFIG_MICROCODE_OLD_INTERFACE
277static int do_microcode_update(const void __user *buf, size_t size)
278{
279 int error = 0;
280 int cpu;
281
282 for_each_online_cpu(cpu) {
283 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
284 enum ucode_state ustate;
285
286 if (!uci->valid)
287 continue;
288
289 ustate = microcode_ops->request_microcode_user(cpu, buf, size);
290 if (ustate == UCODE_ERROR) {
291 error = -1;
292 break;
293 } else if (ustate == UCODE_OK)
294 apply_microcode_on_target(cpu);
295 }
296
297 return error;
298}
299
300static int microcode_open(struct inode *inode, struct file *file)
301{
302 return capable(CAP_SYS_RAWIO) ? nonseekable_open(inode, file) : -EPERM;
303}
304
305static ssize_t microcode_write(struct file *file, const char __user *buf,
306 size_t len, loff_t *ppos)
307{
308 ssize_t ret = -EINVAL;
309
310 if ((len >> PAGE_SHIFT) > totalram_pages) {
311 pr_err("too much data (max %ld pages)\n", totalram_pages);
312 return ret;
313 }
314
315 get_online_cpus();
316 mutex_lock(µcode_mutex);
317
318 if (do_microcode_update(buf, len) == 0)
319 ret = (ssize_t)len;
320
321 if (ret > 0)
322 perf_check_microcode();
323
324 mutex_unlock(µcode_mutex);
325 put_online_cpus();
326
327 return ret;
328}
329
330static const struct file_operations microcode_fops = {
331 .owner = THIS_MODULE,
332 .write = microcode_write,
333 .open = microcode_open,
334 .llseek = no_llseek,
335};
336
337static struct miscdevice microcode_dev = {
338 .minor = MICROCODE_MINOR,
339 .name = "microcode",
340 .nodename = "cpu/microcode",
341 .fops = µcode_fops,
342};
343
344static int __init microcode_dev_init(void)
345{
346 int error;
347
348 error = misc_register(µcode_dev);
349 if (error) {
350 pr_err("can't misc_register on minor=%d\n", MICROCODE_MINOR);
351 return error;
352 }
353
354 return 0;
355}
356
357static void __exit microcode_dev_exit(void)
358{
359 misc_deregister(µcode_dev);
360}
361#else
362#define microcode_dev_init() 0
363#define microcode_dev_exit() do { } while (0)
364#endif
365
366/* fake device for request_firmware */
367static struct platform_device *microcode_pdev;
368
369static int reload_for_cpu(int cpu)
370{
371 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
372 enum ucode_state ustate;
373 int err = 0;
374
375 if (!uci->valid)
376 return err;
377
378 ustate = microcode_ops->request_microcode_fw(cpu, µcode_pdev->dev, true);
379 if (ustate == UCODE_OK)
380 apply_microcode_on_target(cpu);
381 else
382 if (ustate == UCODE_ERROR)
383 err = -EINVAL;
384 return err;
385}
386
387static ssize_t reload_store(struct device *dev,
388 struct device_attribute *attr,
389 const char *buf, size_t size)
390{
391 unsigned long val;
392 int cpu;
393 ssize_t ret = 0, tmp_ret;
394
395 ret = kstrtoul(buf, 0, &val);
396 if (ret)
397 return ret;
398
399 if (val != 1)
400 return size;
401
402 get_online_cpus();
403 mutex_lock(µcode_mutex);
404 for_each_online_cpu(cpu) {
405 tmp_ret = reload_for_cpu(cpu);
406 if (tmp_ret != 0)
407 pr_warn("Error reloading microcode on CPU %d\n", cpu);
408
409 /* save retval of the first encountered reload error */
410 if (!ret)
411 ret = tmp_ret;
412 }
413 if (!ret)
414 perf_check_microcode();
415 mutex_unlock(µcode_mutex);
416 put_online_cpus();
417
418 if (!ret)
419 ret = size;
420
421 return ret;
422}
423
424static ssize_t version_show(struct device *dev,
425 struct device_attribute *attr, char *buf)
426{
427 struct ucode_cpu_info *uci = ucode_cpu_info + dev->id;
428
429 return sprintf(buf, "0x%x\n", uci->cpu_sig.rev);
430}
431
432static ssize_t pf_show(struct device *dev,
433 struct device_attribute *attr, char *buf)
434{
435 struct ucode_cpu_info *uci = ucode_cpu_info + dev->id;
436
437 return sprintf(buf, "0x%x\n", uci->cpu_sig.pf);
438}
439
440static DEVICE_ATTR(reload, 0200, NULL, reload_store);
441static DEVICE_ATTR(version, 0400, version_show, NULL);
442static DEVICE_ATTR(processor_flags, 0400, pf_show, NULL);
443
444static struct attribute *mc_default_attrs[] = {
445 &dev_attr_version.attr,
446 &dev_attr_processor_flags.attr,
447 NULL
448};
449
450static struct attribute_group mc_attr_group = {
451 .attrs = mc_default_attrs,
452 .name = "microcode",
453};
454
455static void microcode_fini_cpu(int cpu)
456{
457 microcode_ops->microcode_fini_cpu(cpu);
458}
459
460static enum ucode_state microcode_resume_cpu(int cpu)
461{
462 pr_debug("CPU%d updated upon resume\n", cpu);
463
464 if (apply_microcode_on_target(cpu))
465 return UCODE_ERROR;
466
467 return UCODE_OK;
468}
469
470static enum ucode_state microcode_init_cpu(int cpu, bool refresh_fw)
471{
472 enum ucode_state ustate;
473 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
474
475 if (uci->valid)
476 return UCODE_OK;
477
478 if (collect_cpu_info(cpu))
479 return UCODE_ERROR;
480
481 /* --dimm. Trigger a delayed update? */
482 if (system_state != SYSTEM_RUNNING)
483 return UCODE_NFOUND;
484
485 ustate = microcode_ops->request_microcode_fw(cpu, µcode_pdev->dev,
486 refresh_fw);
487
488 if (ustate == UCODE_OK) {
489 pr_debug("CPU%d updated upon init\n", cpu);
490 apply_microcode_on_target(cpu);
491 }
492
493 return ustate;
494}
495
496static enum ucode_state microcode_update_cpu(int cpu)
497{
498 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
499
500 if (uci->valid)
501 return microcode_resume_cpu(cpu);
502
503 return microcode_init_cpu(cpu, false);
504}
505
506static int mc_device_add(struct device *dev, struct subsys_interface *sif)
507{
508 int err, cpu = dev->id;
509
510 if (!cpu_online(cpu))
511 return 0;
512
513 pr_debug("CPU%d added\n", cpu);
514
515 err = sysfs_create_group(&dev->kobj, &mc_attr_group);
516 if (err)
517 return err;
518
519 if (microcode_init_cpu(cpu, true) == UCODE_ERROR)
520 return -EINVAL;
521
522 return err;
523}
524
525static void mc_device_remove(struct device *dev, struct subsys_interface *sif)
526{
527 int cpu = dev->id;
528
529 if (!cpu_online(cpu))
530 return;
531
532 pr_debug("CPU%d removed\n", cpu);
533 microcode_fini_cpu(cpu);
534 sysfs_remove_group(&dev->kobj, &mc_attr_group);
535}
536
537static struct subsys_interface mc_cpu_interface = {
538 .name = "microcode",
539 .subsys = &cpu_subsys,
540 .add_dev = mc_device_add,
541 .remove_dev = mc_device_remove,
542};
543
544/**
545 * mc_bp_resume - Update boot CPU microcode during resume.
546 */
547static void mc_bp_resume(void)
548{
549 int cpu = smp_processor_id();
550 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
551
552 if (uci->valid && uci->mc)
553 microcode_ops->apply_microcode(cpu);
554 else if (!uci->mc)
555 reload_early_microcode();
556}
557
558static struct syscore_ops mc_syscore_ops = {
559 .resume = mc_bp_resume,
560};
561
562static int
563mc_cpu_callback(struct notifier_block *nb, unsigned long action, void *hcpu)
564{
565 unsigned int cpu = (unsigned long)hcpu;
566 struct device *dev;
567
568 dev = get_cpu_device(cpu);
569
570 switch (action & ~CPU_TASKS_FROZEN) {
571 case CPU_ONLINE:
572 microcode_update_cpu(cpu);
573 pr_debug("CPU%d added\n", cpu);
574 /*
575 * "break" is missing on purpose here because we want to fall
576 * through in order to create the sysfs group.
577 */
578
579 case CPU_DOWN_FAILED:
580 if (sysfs_create_group(&dev->kobj, &mc_attr_group))
581 pr_err("Failed to create group for CPU%d\n", cpu);
582 break;
583
584 case CPU_DOWN_PREPARE:
585 /* Suspend is in progress, only remove the interface */
586 sysfs_remove_group(&dev->kobj, &mc_attr_group);
587 pr_debug("CPU%d removed\n", cpu);
588 break;
589
590 /*
591 * case CPU_DEAD:
592 *
593 * When a CPU goes offline, don't free up or invalidate the copy of
594 * the microcode in kernel memory, so that we can reuse it when the
595 * CPU comes back online without unnecessarily requesting the userspace
596 * for it again.
597 */
598 }
599
600 /* The CPU refused to come up during a system resume */
601 if (action == CPU_UP_CANCELED_FROZEN)
602 microcode_fini_cpu(cpu);
603
604 return NOTIFY_OK;
605}
606
607static struct notifier_block mc_cpu_notifier = {
608 .notifier_call = mc_cpu_callback,
609};
610
611static struct attribute *cpu_root_microcode_attrs[] = {
612 &dev_attr_reload.attr,
613 NULL
614};
615
616static struct attribute_group cpu_root_microcode_group = {
617 .name = "microcode",
618 .attrs = cpu_root_microcode_attrs,
619};
620
621int __init microcode_init(void)
622{
623 struct cpuinfo_x86 *c = &boot_cpu_data;
624 int error;
625
626 if (dis_ucode_ldr)
627 return -EINVAL;
628
629 if (c->x86_vendor == X86_VENDOR_INTEL)
630 microcode_ops = init_intel_microcode();
631 else if (c->x86_vendor == X86_VENDOR_AMD)
632 microcode_ops = init_amd_microcode();
633 else
634 pr_err("no support for this CPU vendor\n");
635
636 if (!microcode_ops)
637 return -ENODEV;
638
639 microcode_pdev = platform_device_register_simple("microcode", -1,
640 NULL, 0);
641 if (IS_ERR(microcode_pdev))
642 return PTR_ERR(microcode_pdev);
643
644 get_online_cpus();
645 mutex_lock(µcode_mutex);
646
647 error = subsys_interface_register(&mc_cpu_interface);
648 if (!error)
649 perf_check_microcode();
650 mutex_unlock(µcode_mutex);
651 put_online_cpus();
652
653 if (error)
654 goto out_pdev;
655
656 error = sysfs_create_group(&cpu_subsys.dev_root->kobj,
657 &cpu_root_microcode_group);
658
659 if (error) {
660 pr_err("Error creating microcode group!\n");
661 goto out_driver;
662 }
663
664 error = microcode_dev_init();
665 if (error)
666 goto out_ucode_group;
667
668 register_syscore_ops(&mc_syscore_ops);
669 register_hotcpu_notifier(&mc_cpu_notifier);
670
671 pr_info("Microcode Update Driver: v" MICROCODE_VERSION
672 " <tigran@aivazian.fsnet.co.uk>, Peter Oruba\n");
673
674 return 0;
675
676 out_ucode_group:
677 sysfs_remove_group(&cpu_subsys.dev_root->kobj,
678 &cpu_root_microcode_group);
679
680 out_driver:
681 get_online_cpus();
682 mutex_lock(µcode_mutex);
683
684 subsys_interface_unregister(&mc_cpu_interface);
685
686 mutex_unlock(µcode_mutex);
687 put_online_cpus();
688
689 out_pdev:
690 platform_device_unregister(microcode_pdev);
691 return error;
692
693}
694late_initcall(microcode_init);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * CPU Microcode Update Driver for Linux
4 *
5 * Copyright (C) 2000-2006 Tigran Aivazian <aivazian.tigran@gmail.com>
6 * 2006 Shaohua Li <shaohua.li@intel.com>
7 * 2013-2016 Borislav Petkov <bp@alien8.de>
8 *
9 * X86 CPU microcode early update for Linux:
10 *
11 * Copyright (C) 2012 Fenghua Yu <fenghua.yu@intel.com>
12 * H Peter Anvin" <hpa@zytor.com>
13 * (C) 2015 Borislav Petkov <bp@alien8.de>
14 *
15 * This driver allows to upgrade microcode on x86 processors.
16 */
17
18#define pr_fmt(fmt) "microcode: " fmt
19
20#include <linux/platform_device.h>
21#include <linux/stop_machine.h>
22#include <linux/syscore_ops.h>
23#include <linux/miscdevice.h>
24#include <linux/capability.h>
25#include <linux/firmware.h>
26#include <linux/kernel.h>
27#include <linux/delay.h>
28#include <linux/mutex.h>
29#include <linux/cpu.h>
30#include <linux/nmi.h>
31#include <linux/fs.h>
32#include <linux/mm.h>
33
34#include <asm/microcode_intel.h>
35#include <asm/cpu_device_id.h>
36#include <asm/microcode_amd.h>
37#include <asm/perf_event.h>
38#include <asm/microcode.h>
39#include <asm/processor.h>
40#include <asm/cmdline.h>
41#include <asm/setup.h>
42
43#define DRIVER_VERSION "2.2"
44
45static struct microcode_ops *microcode_ops;
46static bool dis_ucode_ldr = true;
47
48bool initrd_gone;
49
50LIST_HEAD(microcode_cache);
51
52/*
53 * Synchronization.
54 *
55 * All non cpu-hotplug-callback call sites use:
56 *
57 * - microcode_mutex to synchronize with each other;
58 * - get/put_online_cpus() to synchronize with
59 * the cpu-hotplug-callback call sites.
60 *
61 * We guarantee that only a single cpu is being
62 * updated at any particular moment of time.
63 */
64static DEFINE_MUTEX(microcode_mutex);
65
66struct ucode_cpu_info ucode_cpu_info[NR_CPUS];
67
68struct cpu_info_ctx {
69 struct cpu_signature *cpu_sig;
70 int err;
71};
72
73/*
74 * Those patch levels cannot be updated to newer ones and thus should be final.
75 */
76static u32 final_levels[] = {
77 0x01000098,
78 0x0100009f,
79 0x010000af,
80 0, /* T-101 terminator */
81};
82
83/*
84 * Check the current patch level on this CPU.
85 *
86 * Returns:
87 * - true: if update should stop
88 * - false: otherwise
89 */
90static bool amd_check_current_patch_level(void)
91{
92 u32 lvl, dummy, i;
93 u32 *levels;
94
95 native_rdmsr(MSR_AMD64_PATCH_LEVEL, lvl, dummy);
96
97 if (IS_ENABLED(CONFIG_X86_32))
98 levels = (u32 *)__pa_nodebug(&final_levels);
99 else
100 levels = final_levels;
101
102 for (i = 0; levels[i]; i++) {
103 if (lvl == levels[i])
104 return true;
105 }
106 return false;
107}
108
109static bool __init check_loader_disabled_bsp(void)
110{
111 static const char *__dis_opt_str = "dis_ucode_ldr";
112
113#ifdef CONFIG_X86_32
114 const char *cmdline = (const char *)__pa_nodebug(boot_command_line);
115 const char *option = (const char *)__pa_nodebug(__dis_opt_str);
116 bool *res = (bool *)__pa_nodebug(&dis_ucode_ldr);
117
118#else /* CONFIG_X86_64 */
119 const char *cmdline = boot_command_line;
120 const char *option = __dis_opt_str;
121 bool *res = &dis_ucode_ldr;
122#endif
123
124 /*
125 * CPUID(1).ECX[31]: reserved for hypervisor use. This is still not
126 * completely accurate as xen pv guests don't see that CPUID bit set but
127 * that's good enough as they don't land on the BSP path anyway.
128 */
129 if (native_cpuid_ecx(1) & BIT(31))
130 return *res;
131
132 if (x86_cpuid_vendor() == X86_VENDOR_AMD) {
133 if (amd_check_current_patch_level())
134 return *res;
135 }
136
137 if (cmdline_find_option_bool(cmdline, option) <= 0)
138 *res = false;
139
140 return *res;
141}
142
143extern struct builtin_fw __start_builtin_fw[];
144extern struct builtin_fw __end_builtin_fw[];
145
146bool get_builtin_firmware(struct cpio_data *cd, const char *name)
147{
148 struct builtin_fw *b_fw;
149
150 for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
151 if (!strcmp(name, b_fw->name)) {
152 cd->size = b_fw->size;
153 cd->data = b_fw->data;
154 return true;
155 }
156 }
157 return false;
158}
159
160void __init load_ucode_bsp(void)
161{
162 unsigned int cpuid_1_eax;
163 bool intel = true;
164
165 if (!have_cpuid_p())
166 return;
167
168 cpuid_1_eax = native_cpuid_eax(1);
169
170 switch (x86_cpuid_vendor()) {
171 case X86_VENDOR_INTEL:
172 if (x86_family(cpuid_1_eax) < 6)
173 return;
174 break;
175
176 case X86_VENDOR_AMD:
177 if (x86_family(cpuid_1_eax) < 0x10)
178 return;
179 intel = false;
180 break;
181
182 default:
183 return;
184 }
185
186 if (check_loader_disabled_bsp())
187 return;
188
189 if (intel)
190 load_ucode_intel_bsp();
191 else
192 load_ucode_amd_bsp(cpuid_1_eax);
193}
194
195static bool check_loader_disabled_ap(void)
196{
197#ifdef CONFIG_X86_32
198 return *((bool *)__pa_nodebug(&dis_ucode_ldr));
199#else
200 return dis_ucode_ldr;
201#endif
202}
203
204void load_ucode_ap(void)
205{
206 unsigned int cpuid_1_eax;
207
208 if (check_loader_disabled_ap())
209 return;
210
211 cpuid_1_eax = native_cpuid_eax(1);
212
213 switch (x86_cpuid_vendor()) {
214 case X86_VENDOR_INTEL:
215 if (x86_family(cpuid_1_eax) >= 6)
216 load_ucode_intel_ap();
217 break;
218 case X86_VENDOR_AMD:
219 if (x86_family(cpuid_1_eax) >= 0x10)
220 load_ucode_amd_ap(cpuid_1_eax);
221 break;
222 default:
223 break;
224 }
225}
226
227static int __init save_microcode_in_initrd(void)
228{
229 struct cpuinfo_x86 *c = &boot_cpu_data;
230 int ret = -EINVAL;
231
232 switch (c->x86_vendor) {
233 case X86_VENDOR_INTEL:
234 if (c->x86 >= 6)
235 ret = save_microcode_in_initrd_intel();
236 break;
237 case X86_VENDOR_AMD:
238 if (c->x86 >= 0x10)
239 ret = save_microcode_in_initrd_amd(cpuid_eax(1));
240 break;
241 default:
242 break;
243 }
244
245 initrd_gone = true;
246
247 return ret;
248}
249
250struct cpio_data find_microcode_in_initrd(const char *path, bool use_pa)
251{
252#ifdef CONFIG_BLK_DEV_INITRD
253 unsigned long start = 0;
254 size_t size;
255
256#ifdef CONFIG_X86_32
257 struct boot_params *params;
258
259 if (use_pa)
260 params = (struct boot_params *)__pa_nodebug(&boot_params);
261 else
262 params = &boot_params;
263
264 size = params->hdr.ramdisk_size;
265
266 /*
267 * Set start only if we have an initrd image. We cannot use initrd_start
268 * because it is not set that early yet.
269 */
270 if (size)
271 start = params->hdr.ramdisk_image;
272
273# else /* CONFIG_X86_64 */
274 size = (unsigned long)boot_params.ext_ramdisk_size << 32;
275 size |= boot_params.hdr.ramdisk_size;
276
277 if (size) {
278 start = (unsigned long)boot_params.ext_ramdisk_image << 32;
279 start |= boot_params.hdr.ramdisk_image;
280
281 start += PAGE_OFFSET;
282 }
283# endif
284
285 /*
286 * Fixup the start address: after reserve_initrd() runs, initrd_start
287 * has the virtual address of the beginning of the initrd. It also
288 * possibly relocates the ramdisk. In either case, initrd_start contains
289 * the updated address so use that instead.
290 *
291 * initrd_gone is for the hotplug case where we've thrown out initrd
292 * already.
293 */
294 if (!use_pa) {
295 if (initrd_gone)
296 return (struct cpio_data){ NULL, 0, "" };
297 if (initrd_start)
298 start = initrd_start;
299 } else {
300 /*
301 * The picture with physical addresses is a bit different: we
302 * need to get the *physical* address to which the ramdisk was
303 * relocated, i.e., relocated_ramdisk (not initrd_start) and
304 * since we're running from physical addresses, we need to access
305 * relocated_ramdisk through its *physical* address too.
306 */
307 u64 *rr = (u64 *)__pa_nodebug(&relocated_ramdisk);
308 if (*rr)
309 start = *rr;
310 }
311
312 return find_cpio_data(path, (void *)start, size, NULL);
313#else /* !CONFIG_BLK_DEV_INITRD */
314 return (struct cpio_data){ NULL, 0, "" };
315#endif
316}
317
318void reload_early_microcode(void)
319{
320 int vendor, family;
321
322 vendor = x86_cpuid_vendor();
323 family = x86_cpuid_family();
324
325 switch (vendor) {
326 case X86_VENDOR_INTEL:
327 if (family >= 6)
328 reload_ucode_intel();
329 break;
330 case X86_VENDOR_AMD:
331 if (family >= 0x10)
332 reload_ucode_amd();
333 break;
334 default:
335 break;
336 }
337}
338
339static void collect_cpu_info_local(void *arg)
340{
341 struct cpu_info_ctx *ctx = arg;
342
343 ctx->err = microcode_ops->collect_cpu_info(smp_processor_id(),
344 ctx->cpu_sig);
345}
346
347static int collect_cpu_info_on_target(int cpu, struct cpu_signature *cpu_sig)
348{
349 struct cpu_info_ctx ctx = { .cpu_sig = cpu_sig, .err = 0 };
350 int ret;
351
352 ret = smp_call_function_single(cpu, collect_cpu_info_local, &ctx, 1);
353 if (!ret)
354 ret = ctx.err;
355
356 return ret;
357}
358
359static int collect_cpu_info(int cpu)
360{
361 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
362 int ret;
363
364 memset(uci, 0, sizeof(*uci));
365
366 ret = collect_cpu_info_on_target(cpu, &uci->cpu_sig);
367 if (!ret)
368 uci->valid = 1;
369
370 return ret;
371}
372
373static void apply_microcode_local(void *arg)
374{
375 enum ucode_state *err = arg;
376
377 *err = microcode_ops->apply_microcode(smp_processor_id());
378}
379
380static int apply_microcode_on_target(int cpu)
381{
382 enum ucode_state err;
383 int ret;
384
385 ret = smp_call_function_single(cpu, apply_microcode_local, &err, 1);
386 if (!ret) {
387 if (err == UCODE_ERROR)
388 ret = 1;
389 }
390 return ret;
391}
392
393#ifdef CONFIG_MICROCODE_OLD_INTERFACE
394static int do_microcode_update(const void __user *buf, size_t size)
395{
396 int error = 0;
397 int cpu;
398
399 for_each_online_cpu(cpu) {
400 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
401 enum ucode_state ustate;
402
403 if (!uci->valid)
404 continue;
405
406 ustate = microcode_ops->request_microcode_user(cpu, buf, size);
407 if (ustate == UCODE_ERROR) {
408 error = -1;
409 break;
410 } else if (ustate == UCODE_NEW) {
411 apply_microcode_on_target(cpu);
412 }
413 }
414
415 return error;
416}
417
418static int microcode_open(struct inode *inode, struct file *file)
419{
420 return capable(CAP_SYS_RAWIO) ? stream_open(inode, file) : -EPERM;
421}
422
423static ssize_t microcode_write(struct file *file, const char __user *buf,
424 size_t len, loff_t *ppos)
425{
426 ssize_t ret = -EINVAL;
427 unsigned long nr_pages = totalram_pages();
428
429 if ((len >> PAGE_SHIFT) > nr_pages) {
430 pr_err("too much data (max %ld pages)\n", nr_pages);
431 return ret;
432 }
433
434 get_online_cpus();
435 mutex_lock(µcode_mutex);
436
437 if (do_microcode_update(buf, len) == 0)
438 ret = (ssize_t)len;
439
440 if (ret > 0)
441 perf_check_microcode();
442
443 mutex_unlock(µcode_mutex);
444 put_online_cpus();
445
446 return ret;
447}
448
449static const struct file_operations microcode_fops = {
450 .owner = THIS_MODULE,
451 .write = microcode_write,
452 .open = microcode_open,
453 .llseek = no_llseek,
454};
455
456static struct miscdevice microcode_dev = {
457 .minor = MICROCODE_MINOR,
458 .name = "microcode",
459 .nodename = "cpu/microcode",
460 .fops = µcode_fops,
461};
462
463static int __init microcode_dev_init(void)
464{
465 int error;
466
467 error = misc_register(µcode_dev);
468 if (error) {
469 pr_err("can't misc_register on minor=%d\n", MICROCODE_MINOR);
470 return error;
471 }
472
473 return 0;
474}
475
476static void __exit microcode_dev_exit(void)
477{
478 misc_deregister(µcode_dev);
479}
480#else
481#define microcode_dev_init() 0
482#define microcode_dev_exit() do { } while (0)
483#endif
484
485/* fake device for request_firmware */
486static struct platform_device *microcode_pdev;
487
488/*
489 * Late loading dance. Why the heavy-handed stomp_machine effort?
490 *
491 * - HT siblings must be idle and not execute other code while the other sibling
492 * is loading microcode in order to avoid any negative interactions caused by
493 * the loading.
494 *
495 * - In addition, microcode update on the cores must be serialized until this
496 * requirement can be relaxed in the future. Right now, this is conservative
497 * and good.
498 */
499#define SPINUNIT 100 /* 100 nsec */
500
501static int check_online_cpus(void)
502{
503 unsigned int cpu;
504
505 /*
506 * Make sure all CPUs are online. It's fine for SMT to be disabled if
507 * all the primary threads are still online.
508 */
509 for_each_present_cpu(cpu) {
510 if (topology_is_primary_thread(cpu) && !cpu_online(cpu)) {
511 pr_err("Not all CPUs online, aborting microcode update.\n");
512 return -EINVAL;
513 }
514 }
515
516 return 0;
517}
518
519static atomic_t late_cpus_in;
520static atomic_t late_cpus_out;
521
522static int __wait_for_cpus(atomic_t *t, long long timeout)
523{
524 int all_cpus = num_online_cpus();
525
526 atomic_inc(t);
527
528 while (atomic_read(t) < all_cpus) {
529 if (timeout < SPINUNIT) {
530 pr_err("Timeout while waiting for CPUs rendezvous, remaining: %d\n",
531 all_cpus - atomic_read(t));
532 return 1;
533 }
534
535 ndelay(SPINUNIT);
536 timeout -= SPINUNIT;
537
538 touch_nmi_watchdog();
539 }
540 return 0;
541}
542
543/*
544 * Returns:
545 * < 0 - on error
546 * 0 - success (no update done or microcode was updated)
547 */
548static int __reload_late(void *info)
549{
550 int cpu = smp_processor_id();
551 enum ucode_state err;
552 int ret = 0;
553
554 /*
555 * Wait for all CPUs to arrive. A load will not be attempted unless all
556 * CPUs show up.
557 * */
558 if (__wait_for_cpus(&late_cpus_in, NSEC_PER_SEC))
559 return -1;
560
561 /*
562 * On an SMT system, it suffices to load the microcode on one sibling of
563 * the core because the microcode engine is shared between the threads.
564 * Synchronization still needs to take place so that no concurrent
565 * loading attempts happen on multiple threads of an SMT core. See
566 * below.
567 */
568 if (cpumask_first(topology_sibling_cpumask(cpu)) == cpu)
569 apply_microcode_local(&err);
570 else
571 goto wait_for_siblings;
572
573 if (err >= UCODE_NFOUND) {
574 if (err == UCODE_ERROR)
575 pr_warn("Error reloading microcode on CPU %d\n", cpu);
576
577 ret = -1;
578 }
579
580wait_for_siblings:
581 if (__wait_for_cpus(&late_cpus_out, NSEC_PER_SEC))
582 panic("Timeout during microcode update!\n");
583
584 /*
585 * At least one thread has completed update on each core.
586 * For others, simply call the update to make sure the
587 * per-cpu cpuinfo can be updated with right microcode
588 * revision.
589 */
590 if (cpumask_first(topology_sibling_cpumask(cpu)) != cpu)
591 apply_microcode_local(&err);
592
593 return ret;
594}
595
596/*
597 * Reload microcode late on all CPUs. Wait for a sec until they
598 * all gather together.
599 */
600static int microcode_reload_late(void)
601{
602 int ret;
603
604 atomic_set(&late_cpus_in, 0);
605 atomic_set(&late_cpus_out, 0);
606
607 ret = stop_machine_cpuslocked(__reload_late, NULL, cpu_online_mask);
608 if (ret == 0)
609 microcode_check();
610
611 pr_info("Reload completed, microcode revision: 0x%x\n", boot_cpu_data.microcode);
612
613 return ret;
614}
615
616static ssize_t reload_store(struct device *dev,
617 struct device_attribute *attr,
618 const char *buf, size_t size)
619{
620 enum ucode_state tmp_ret = UCODE_OK;
621 int bsp = boot_cpu_data.cpu_index;
622 unsigned long val;
623 ssize_t ret = 0;
624
625 ret = kstrtoul(buf, 0, &val);
626 if (ret)
627 return ret;
628
629 if (val != 1)
630 return size;
631
632 tmp_ret = microcode_ops->request_microcode_fw(bsp, µcode_pdev->dev, true);
633 if (tmp_ret != UCODE_NEW)
634 return size;
635
636 get_online_cpus();
637
638 ret = check_online_cpus();
639 if (ret)
640 goto put;
641
642 mutex_lock(µcode_mutex);
643 ret = microcode_reload_late();
644 mutex_unlock(µcode_mutex);
645
646put:
647 put_online_cpus();
648
649 if (ret == 0)
650 ret = size;
651
652 return ret;
653}
654
655static ssize_t version_show(struct device *dev,
656 struct device_attribute *attr, char *buf)
657{
658 struct ucode_cpu_info *uci = ucode_cpu_info + dev->id;
659
660 return sprintf(buf, "0x%x\n", uci->cpu_sig.rev);
661}
662
663static ssize_t pf_show(struct device *dev,
664 struct device_attribute *attr, char *buf)
665{
666 struct ucode_cpu_info *uci = ucode_cpu_info + dev->id;
667
668 return sprintf(buf, "0x%x\n", uci->cpu_sig.pf);
669}
670
671static DEVICE_ATTR_WO(reload);
672static DEVICE_ATTR(version, 0444, version_show, NULL);
673static DEVICE_ATTR(processor_flags, 0444, pf_show, NULL);
674
675static struct attribute *mc_default_attrs[] = {
676 &dev_attr_version.attr,
677 &dev_attr_processor_flags.attr,
678 NULL
679};
680
681static const struct attribute_group mc_attr_group = {
682 .attrs = mc_default_attrs,
683 .name = "microcode",
684};
685
686static void microcode_fini_cpu(int cpu)
687{
688 if (microcode_ops->microcode_fini_cpu)
689 microcode_ops->microcode_fini_cpu(cpu);
690}
691
692static enum ucode_state microcode_resume_cpu(int cpu)
693{
694 if (apply_microcode_on_target(cpu))
695 return UCODE_ERROR;
696
697 pr_debug("CPU%d updated upon resume\n", cpu);
698
699 return UCODE_OK;
700}
701
702static enum ucode_state microcode_init_cpu(int cpu, bool refresh_fw)
703{
704 enum ucode_state ustate;
705 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
706
707 if (uci->valid)
708 return UCODE_OK;
709
710 if (collect_cpu_info(cpu))
711 return UCODE_ERROR;
712
713 /* --dimm. Trigger a delayed update? */
714 if (system_state != SYSTEM_RUNNING)
715 return UCODE_NFOUND;
716
717 ustate = microcode_ops->request_microcode_fw(cpu, µcode_pdev->dev, refresh_fw);
718 if (ustate == UCODE_NEW) {
719 pr_debug("CPU%d updated upon init\n", cpu);
720 apply_microcode_on_target(cpu);
721 }
722
723 return ustate;
724}
725
726static enum ucode_state microcode_update_cpu(int cpu)
727{
728 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
729
730 /* Refresh CPU microcode revision after resume. */
731 collect_cpu_info(cpu);
732
733 if (uci->valid)
734 return microcode_resume_cpu(cpu);
735
736 return microcode_init_cpu(cpu, false);
737}
738
739static int mc_device_add(struct device *dev, struct subsys_interface *sif)
740{
741 int err, cpu = dev->id;
742
743 if (!cpu_online(cpu))
744 return 0;
745
746 pr_debug("CPU%d added\n", cpu);
747
748 err = sysfs_create_group(&dev->kobj, &mc_attr_group);
749 if (err)
750 return err;
751
752 if (microcode_init_cpu(cpu, true) == UCODE_ERROR)
753 return -EINVAL;
754
755 return err;
756}
757
758static void mc_device_remove(struct device *dev, struct subsys_interface *sif)
759{
760 int cpu = dev->id;
761
762 if (!cpu_online(cpu))
763 return;
764
765 pr_debug("CPU%d removed\n", cpu);
766 microcode_fini_cpu(cpu);
767 sysfs_remove_group(&dev->kobj, &mc_attr_group);
768}
769
770static struct subsys_interface mc_cpu_interface = {
771 .name = "microcode",
772 .subsys = &cpu_subsys,
773 .add_dev = mc_device_add,
774 .remove_dev = mc_device_remove,
775};
776
777/**
778 * mc_bp_resume - Update boot CPU microcode during resume.
779 */
780static void mc_bp_resume(void)
781{
782 int cpu = smp_processor_id();
783 struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
784
785 if (uci->valid && uci->mc)
786 microcode_ops->apply_microcode(cpu);
787 else if (!uci->mc)
788 reload_early_microcode();
789}
790
791static struct syscore_ops mc_syscore_ops = {
792 .resume = mc_bp_resume,
793};
794
795static int mc_cpu_starting(unsigned int cpu)
796{
797 microcode_update_cpu(cpu);
798 pr_debug("CPU%d added\n", cpu);
799 return 0;
800}
801
802static int mc_cpu_online(unsigned int cpu)
803{
804 struct device *dev = get_cpu_device(cpu);
805
806 if (sysfs_create_group(&dev->kobj, &mc_attr_group))
807 pr_err("Failed to create group for CPU%d\n", cpu);
808 return 0;
809}
810
811static int mc_cpu_down_prep(unsigned int cpu)
812{
813 struct device *dev;
814
815 dev = get_cpu_device(cpu);
816 /* Suspend is in progress, only remove the interface */
817 sysfs_remove_group(&dev->kobj, &mc_attr_group);
818 pr_debug("CPU%d removed\n", cpu);
819
820 return 0;
821}
822
823static struct attribute *cpu_root_microcode_attrs[] = {
824 &dev_attr_reload.attr,
825 NULL
826};
827
828static const struct attribute_group cpu_root_microcode_group = {
829 .name = "microcode",
830 .attrs = cpu_root_microcode_attrs,
831};
832
833int __init microcode_init(void)
834{
835 struct cpuinfo_x86 *c = &boot_cpu_data;
836 int error;
837
838 if (dis_ucode_ldr)
839 return -EINVAL;
840
841 if (c->x86_vendor == X86_VENDOR_INTEL)
842 microcode_ops = init_intel_microcode();
843 else if (c->x86_vendor == X86_VENDOR_AMD)
844 microcode_ops = init_amd_microcode();
845 else
846 pr_err("no support for this CPU vendor\n");
847
848 if (!microcode_ops)
849 return -ENODEV;
850
851 microcode_pdev = platform_device_register_simple("microcode", -1,
852 NULL, 0);
853 if (IS_ERR(microcode_pdev))
854 return PTR_ERR(microcode_pdev);
855
856 get_online_cpus();
857 mutex_lock(µcode_mutex);
858
859 error = subsys_interface_register(&mc_cpu_interface);
860 if (!error)
861 perf_check_microcode();
862 mutex_unlock(µcode_mutex);
863 put_online_cpus();
864
865 if (error)
866 goto out_pdev;
867
868 error = sysfs_create_group(&cpu_subsys.dev_root->kobj,
869 &cpu_root_microcode_group);
870
871 if (error) {
872 pr_err("Error creating microcode group!\n");
873 goto out_driver;
874 }
875
876 error = microcode_dev_init();
877 if (error)
878 goto out_ucode_group;
879
880 register_syscore_ops(&mc_syscore_ops);
881 cpuhp_setup_state_nocalls(CPUHP_AP_MICROCODE_LOADER, "x86/microcode:starting",
882 mc_cpu_starting, NULL);
883 cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "x86/microcode:online",
884 mc_cpu_online, mc_cpu_down_prep);
885
886 pr_info("Microcode Update Driver: v%s.", DRIVER_VERSION);
887
888 return 0;
889
890 out_ucode_group:
891 sysfs_remove_group(&cpu_subsys.dev_root->kobj,
892 &cpu_root_microcode_group);
893
894 out_driver:
895 get_online_cpus();
896 mutex_lock(µcode_mutex);
897
898 subsys_interface_unregister(&mc_cpu_interface);
899
900 mutex_unlock(µcode_mutex);
901 put_online_cpus();
902
903 out_pdev:
904 platform_device_unregister(microcode_pdev);
905 return error;
906
907}
908fs_initcall(save_microcode_in_initrd);
909late_initcall(microcode_init);