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(&microcode_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(&microcode_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			= &microcode_fops,
342};
343
344static int __init microcode_dev_init(void)
345{
346	int error;
347
348	error = misc_register(&microcode_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(&microcode_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, &microcode_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(&microcode_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(&microcode_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, &microcode_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(&microcode_mutex);
646
647	error = subsys_interface_register(&mc_cpu_interface);
648	if (!error)
649		perf_check_microcode();
650	mutex_unlock(&microcode_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(&microcode_mutex);
683
684	subsys_interface_unregister(&mc_cpu_interface);
685
686	mutex_unlock(&microcode_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/*
  2 *	Intel 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 *
  7 *	This driver allows to upgrade microcode on Intel processors
  8 *	belonging to IA-32 family - PentiumPro, Pentium II,
  9 *	Pentium III, Xeon, Pentium 4, etc.
 10 *
 11 *	Reference: Section 8.11 of Volume 3a, IA-32 Intel? Architecture
 12 *	Software Developer's Manual
 13 *	Order Number 253668 or free download from:
 14 *
 15 *	http://developer.intel.com/Assets/PDF/manual/253668.pdf	
 16 *
 17 *	For more information, go to http://www.urbanmyth.org/microcode
 18 *
 19 *	This program is free software; you can redistribute it and/or
 20 *	modify it under the terms of the GNU General Public License
 21 *	as published by the Free Software Foundation; either version
 22 *	2 of the License, or (at your option) any later version.
 23 *
 24 *	1.0	16 Feb 2000, Tigran Aivazian <tigran@sco.com>
 25 *		Initial release.
 26 *	1.01	18 Feb 2000, Tigran Aivazian <tigran@sco.com>
 27 *		Added read() support + cleanups.
 28 *	1.02	21 Feb 2000, Tigran Aivazian <tigran@sco.com>
 29 *		Added 'device trimming' support. open(O_WRONLY) zeroes
 30 *		and frees the saved copy of applied microcode.
 31 *	1.03	29 Feb 2000, Tigran Aivazian <tigran@sco.com>
 32 *		Made to use devfs (/dev/cpu/microcode) + cleanups.
 33 *	1.04	06 Jun 2000, Simon Trimmer <simon@veritas.com>
 34 *		Added misc device support (now uses both devfs and misc).
 35 *		Added MICROCODE_IOCFREE ioctl to clear memory.
 36 *	1.05	09 Jun 2000, Simon Trimmer <simon@veritas.com>
 37 *		Messages for error cases (non Intel & no suitable microcode).
 38 *	1.06	03 Aug 2000, Tigran Aivazian <tigran@veritas.com>
 39 *		Removed ->release(). Removed exclusive open and status bitmap.
 40 *		Added microcode_rwsem to serialize read()/write()/ioctl().
 41 *		Removed global kernel lock usage.
 42 *	1.07	07 Sep 2000, Tigran Aivazian <tigran@veritas.com>
 43 *		Write 0 to 0x8B msr and then cpuid before reading revision,
 44 *		so that it works even if there were no update done by the
 45 *		BIOS. Otherwise, reading from 0x8B gives junk (which happened
 46 *		to be 0 on my machine which is why it worked even when I
 47 *		disabled update by the BIOS)
 48 *		Thanks to Eric W. Biederman <ebiederman@lnxi.com> for the fix.
 49 *	1.08	11 Dec 2000, Richard Schaal <richard.schaal@intel.com> and
 50 *			     Tigran Aivazian <tigran@veritas.com>
 51 *		Intel Pentium 4 processor support and bugfixes.
 52 *	1.09	30 Oct 2001, Tigran Aivazian <tigran@veritas.com>
 53 *		Bugfix for HT (Hyper-Threading) enabled processors
 54 *		whereby processor resources are shared by all logical processors
 55 *		in a single CPU package.
 56 *	1.10	28 Feb 2002 Asit K Mallick <asit.k.mallick@intel.com> and
 57 *		Tigran Aivazian <tigran@veritas.com>,
 58 *		Serialize updates as required on HT processors due to
 59 *		speculative nature of implementation.
 60 *	1.11	22 Mar 2002 Tigran Aivazian <tigran@veritas.com>
 61 *		Fix the panic when writing zero-length microcode chunk.
 62 *	1.12	29 Sep 2003 Nitin Kamble <nitin.a.kamble@intel.com>,
 63 *		Jun Nakajima <jun.nakajima@intel.com>
 64 *		Support for the microcode updates in the new format.
 65 *	1.13	10 Oct 2003 Tigran Aivazian <tigran@veritas.com>
 66 *		Removed ->read() method and obsoleted MICROCODE_IOCFREE ioctl
 67 *		because we no longer hold a copy of applied microcode
 68 *		in kernel memory.
 69 *	1.14	25 Jun 2004 Tigran Aivazian <tigran@veritas.com>
 70 *		Fix sigmatch() macro to handle old CPUs with pf == 0.
 71 *		Thanks to Stuart Swales for pointing out this bug.
 72 */
 73
 74#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 75
 76#include <linux/platform_device.h>
 
 77#include <linux/miscdevice.h>
 78#include <linux/capability.h>
 
 79#include <linux/kernel.h>
 80#include <linux/module.h>
 81#include <linux/mutex.h>
 82#include <linux/cpu.h>
 83#include <linux/fs.h>
 84#include <linux/mm.h>
 85#include <linux/syscore_ops.h>
 86
 
 
 
 
 87#include <asm/microcode.h>
 88#include <asm/processor.h>
 89#include <asm/cpu_device_id.h>
 90#include <asm/perf_event.h>
 91
 92MODULE_DESCRIPTION("Microcode Update Driver");
 93MODULE_AUTHOR("Tigran Aivazian <tigran@aivazian.fsnet.co.uk>");
 94MODULE_LICENSE("GPL");
 95
 96#define MICROCODE_VERSION	"2.00"
 97
 98static struct microcode_ops	*microcode_ops;
 
 99
100/*
101 * Synchronization.
102 *
103 * All non cpu-hotplug-callback call sites use:
104 *
105 * - microcode_mutex to synchronize with each other;
106 * - get/put_online_cpus() to synchronize with
107 *   the cpu-hotplug-callback call sites.
108 *
109 * We guarantee that only a single cpu is being
110 * updated at any particular moment of time.
111 */
112static DEFINE_MUTEX(microcode_mutex);
113
114struct ucode_cpu_info		ucode_cpu_info[NR_CPUS];
115EXPORT_SYMBOL_GPL(ucode_cpu_info);
116
117/*
118 * Operations that are run on a target cpu:
119 */
120
121struct cpu_info_ctx {
122	struct cpu_signature	*cpu_sig;
123	int			err;
124};
125
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
126static void collect_cpu_info_local(void *arg)
127{
128	struct cpu_info_ctx *ctx = arg;
129
130	ctx->err = microcode_ops->collect_cpu_info(smp_processor_id(),
131						   ctx->cpu_sig);
132}
133
134static int collect_cpu_info_on_target(int cpu, struct cpu_signature *cpu_sig)
135{
136	struct cpu_info_ctx ctx = { .cpu_sig = cpu_sig, .err = 0 };
137	int ret;
138
139	ret = smp_call_function_single(cpu, collect_cpu_info_local, &ctx, 1);
140	if (!ret)
141		ret = ctx.err;
142
143	return ret;
144}
145
146static int collect_cpu_info(int cpu)
147{
148	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
149	int ret;
150
151	memset(uci, 0, sizeof(*uci));
152
153	ret = collect_cpu_info_on_target(cpu, &uci->cpu_sig);
154	if (!ret)
155		uci->valid = 1;
156
157	return ret;
158}
159
160struct apply_microcode_ctx {
161	int err;
162};
163
164static void apply_microcode_local(void *arg)
165{
166	struct apply_microcode_ctx *ctx = arg;
167
168	ctx->err = microcode_ops->apply_microcode(smp_processor_id());
169}
170
171static int apply_microcode_on_target(int cpu)
172{
173	struct apply_microcode_ctx ctx = { .err = 0 };
174	int ret;
175
176	ret = smp_call_function_single(cpu, apply_microcode_local, &ctx, 1);
177	if (!ret)
178		ret = ctx.err;
179
180	return ret;
181}
182
183#ifdef CONFIG_MICROCODE_OLD_INTERFACE
184static int do_microcode_update(const void __user *buf, size_t size)
185{
186	int error = 0;
187	int cpu;
188
189	for_each_online_cpu(cpu) {
190		struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
191		enum ucode_state ustate;
192
193		if (!uci->valid)
194			continue;
195
196		ustate = microcode_ops->request_microcode_user(cpu, buf, size);
197		if (ustate == UCODE_ERROR) {
198			error = -1;
199			break;
200		} else if (ustate == UCODE_OK)
201			apply_microcode_on_target(cpu);
202	}
203
204	return error;
205}
206
207static int microcode_open(struct inode *inode, struct file *file)
208{
209	return capable(CAP_SYS_RAWIO) ? nonseekable_open(inode, file) : -EPERM;
210}
211
212static ssize_t microcode_write(struct file *file, const char __user *buf,
213			       size_t len, loff_t *ppos)
214{
215	ssize_t ret = -EINVAL;
216
217	if ((len >> PAGE_SHIFT) > totalram_pages) {
218		pr_err("too much data (max %ld pages)\n", totalram_pages);
219		return ret;
220	}
221
222	get_online_cpus();
223	mutex_lock(&microcode_mutex);
224
225	if (do_microcode_update(buf, len) == 0)
226		ret = (ssize_t)len;
227
228	if (ret > 0)
229		perf_check_microcode();
230
231	mutex_unlock(&microcode_mutex);
232	put_online_cpus();
233
234	return ret;
235}
236
237static const struct file_operations microcode_fops = {
238	.owner			= THIS_MODULE,
239	.write			= microcode_write,
240	.open			= microcode_open,
241	.llseek		= no_llseek,
242};
243
244static struct miscdevice microcode_dev = {
245	.minor			= MICROCODE_MINOR,
246	.name			= "microcode",
247	.nodename		= "cpu/microcode",
248	.fops			= &microcode_fops,
249};
250
251static int __init microcode_dev_init(void)
252{
253	int error;
254
255	error = misc_register(&microcode_dev);
256	if (error) {
257		pr_err("can't misc_register on minor=%d\n", MICROCODE_MINOR);
258		return error;
259	}
260
261	return 0;
262}
263
264static void __exit microcode_dev_exit(void)
265{
266	misc_deregister(&microcode_dev);
267}
268
269MODULE_ALIAS_MISCDEV(MICROCODE_MINOR);
270MODULE_ALIAS("devname:cpu/microcode");
271#else
272#define microcode_dev_init()	0
273#define microcode_dev_exit()	do { } while (0)
274#endif
275
276/* fake device for request_firmware */
277static struct platform_device	*microcode_pdev;
278
279static int reload_for_cpu(int cpu)
280{
281	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
282	enum ucode_state ustate;
283	int err = 0;
284
285	if (!uci->valid)
286		return err;
287
288	ustate = microcode_ops->request_microcode_fw(cpu, &microcode_pdev->dev, true);
289	if (ustate == UCODE_OK)
290		apply_microcode_on_target(cpu);
291	else
292		if (ustate == UCODE_ERROR)
293			err = -EINVAL;
294	return err;
295}
296
297static ssize_t reload_store(struct device *dev,
298			    struct device_attribute *attr,
299			    const char *buf, size_t size)
300{
301	unsigned long val;
302	int cpu;
303	ssize_t ret = 0, tmp_ret;
304
305	ret = kstrtoul(buf, 0, &val);
306	if (ret)
307		return ret;
308
309	if (val != 1)
310		return size;
311
312	get_online_cpus();
313	mutex_lock(&microcode_mutex);
314	for_each_online_cpu(cpu) {
315		tmp_ret = reload_for_cpu(cpu);
316		if (tmp_ret != 0)
317			pr_warn("Error reloading microcode on CPU %d\n", cpu);
318
319		/* save retval of the first encountered reload error */
320		if (!ret)
321			ret = tmp_ret;
322	}
323	if (!ret)
324		perf_check_microcode();
325	mutex_unlock(&microcode_mutex);
326	put_online_cpus();
327
328	if (!ret)
329		ret = size;
330
331	return ret;
332}
333
334static ssize_t version_show(struct device *dev,
335			struct device_attribute *attr, char *buf)
336{
337	struct ucode_cpu_info *uci = ucode_cpu_info + dev->id;
338
339	return sprintf(buf, "0x%x\n", uci->cpu_sig.rev);
340}
341
342static ssize_t pf_show(struct device *dev,
343			struct device_attribute *attr, char *buf)
344{
345	struct ucode_cpu_info *uci = ucode_cpu_info + dev->id;
346
347	return sprintf(buf, "0x%x\n", uci->cpu_sig.pf);
348}
349
350static DEVICE_ATTR(reload, 0200, NULL, reload_store);
351static DEVICE_ATTR(version, 0400, version_show, NULL);
352static DEVICE_ATTR(processor_flags, 0400, pf_show, NULL);
353
354static struct attribute *mc_default_attrs[] = {
355	&dev_attr_version.attr,
356	&dev_attr_processor_flags.attr,
357	NULL
358};
359
360static struct attribute_group mc_attr_group = {
361	.attrs			= mc_default_attrs,
362	.name			= "microcode",
363};
364
365static void microcode_fini_cpu(int cpu)
366{
367	microcode_ops->microcode_fini_cpu(cpu);
368}
369
370static enum ucode_state microcode_resume_cpu(int cpu)
371{
372	pr_debug("CPU%d updated upon resume\n", cpu);
373
374	if (apply_microcode_on_target(cpu))
375		return UCODE_ERROR;
376
377	return UCODE_OK;
378}
379
380static enum ucode_state microcode_init_cpu(int cpu, bool refresh_fw)
381{
382	enum ucode_state ustate;
383	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
384
385	if (uci && uci->valid)
386		return UCODE_OK;
387
388	if (collect_cpu_info(cpu))
389		return UCODE_ERROR;
390
391	/* --dimm. Trigger a delayed update? */
392	if (system_state != SYSTEM_RUNNING)
393		return UCODE_NFOUND;
394
395	ustate = microcode_ops->request_microcode_fw(cpu, &microcode_pdev->dev,
396						     refresh_fw);
397
398	if (ustate == UCODE_OK) {
399		pr_debug("CPU%d updated upon init\n", cpu);
400		apply_microcode_on_target(cpu);
401	}
402
403	return ustate;
404}
405
406static enum ucode_state microcode_update_cpu(int cpu)
407{
408	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
409
410	if (uci->valid)
411		return microcode_resume_cpu(cpu);
412
413	return microcode_init_cpu(cpu, false);
414}
415
416static int mc_device_add(struct device *dev, struct subsys_interface *sif)
417{
418	int err, cpu = dev->id;
419
420	if (!cpu_online(cpu))
421		return 0;
422
423	pr_debug("CPU%d added\n", cpu);
424
425	err = sysfs_create_group(&dev->kobj, &mc_attr_group);
426	if (err)
427		return err;
428
429	if (microcode_init_cpu(cpu, true) == UCODE_ERROR)
430		return -EINVAL;
431
432	return err;
433}
434
435static int mc_device_remove(struct device *dev, struct subsys_interface *sif)
436{
437	int cpu = dev->id;
438
439	if (!cpu_online(cpu))
440		return 0;
441
442	pr_debug("CPU%d removed\n", cpu);
443	microcode_fini_cpu(cpu);
444	sysfs_remove_group(&dev->kobj, &mc_attr_group);
445	return 0;
446}
447
448static struct subsys_interface mc_cpu_interface = {
449	.name			= "microcode",
450	.subsys			= &cpu_subsys,
451	.add_dev		= mc_device_add,
452	.remove_dev		= mc_device_remove,
453};
454
455/**
456 * mc_bp_resume - Update boot CPU microcode during resume.
457 */
458static void mc_bp_resume(void)
459{
460	int cpu = smp_processor_id();
461	struct ucode_cpu_info *uci = ucode_cpu_info + cpu;
462
463	if (uci->valid && uci->mc)
464		microcode_ops->apply_microcode(cpu);
 
 
465}
466
467static struct syscore_ops mc_syscore_ops = {
468	.resume			= mc_bp_resume,
469};
470
471static int
472mc_cpu_callback(struct notifier_block *nb, unsigned long action, void *hcpu)
473{
474	unsigned int cpu = (unsigned long)hcpu;
475	struct device *dev;
476
477	dev = get_cpu_device(cpu);
478
479	switch (action & ~CPU_TASKS_FROZEN) {
480	case CPU_ONLINE:
481		microcode_update_cpu(cpu);
482		pr_debug("CPU%d added\n", cpu);
483		/*
484		 * "break" is missing on purpose here because we want to fall
485		 * through in order to create the sysfs group.
486		 */
487
488	case CPU_DOWN_FAILED:
489		if (sysfs_create_group(&dev->kobj, &mc_attr_group))
490			pr_err("Failed to create group for CPU%d\n", cpu);
491		break;
492
493	case CPU_DOWN_PREPARE:
494		/* Suspend is in progress, only remove the interface */
495		sysfs_remove_group(&dev->kobj, &mc_attr_group);
496		pr_debug("CPU%d removed\n", cpu);
497		break;
498
499	/*
500	 * case CPU_DEAD:
501	 *
502	 * When a CPU goes offline, don't free up or invalidate the copy of
503	 * the microcode in kernel memory, so that we can reuse it when the
504	 * CPU comes back online without unnecessarily requesting the userspace
505	 * for it again.
506	 */
507	}
508
509	/* The CPU refused to come up during a system resume */
510	if (action == CPU_UP_CANCELED_FROZEN)
511		microcode_fini_cpu(cpu);
512
513	return NOTIFY_OK;
514}
515
516static struct notifier_block __refdata mc_cpu_notifier = {
517	.notifier_call	= mc_cpu_callback,
518};
519
520#ifdef MODULE
521/* Autoload on Intel and AMD systems */
522static const struct x86_cpu_id __initconst microcode_id[] = {
523#ifdef CONFIG_MICROCODE_INTEL
524	{ X86_VENDOR_INTEL, X86_FAMILY_ANY, X86_MODEL_ANY, },
525#endif
526#ifdef CONFIG_MICROCODE_AMD
527	{ X86_VENDOR_AMD, X86_FAMILY_ANY, X86_MODEL_ANY, },
528#endif
529	{}
530};
531MODULE_DEVICE_TABLE(x86cpu, microcode_id);
532#endif
533
534static struct attribute *cpu_root_microcode_attrs[] = {
535	&dev_attr_reload.attr,
536	NULL
537};
538
539static struct attribute_group cpu_root_microcode_group = {
540	.name  = "microcode",
541	.attrs = cpu_root_microcode_attrs,
542};
543
544static int __init microcode_init(void)
545{
546	struct cpuinfo_x86 *c = &cpu_data(0);
547	int error;
548
 
 
 
549	if (c->x86_vendor == X86_VENDOR_INTEL)
550		microcode_ops = init_intel_microcode();
551	else if (c->x86_vendor == X86_VENDOR_AMD)
552		microcode_ops = init_amd_microcode();
553	else
554		pr_err("no support for this CPU vendor\n");
555
556	if (!microcode_ops)
557		return -ENODEV;
558
559	microcode_pdev = platform_device_register_simple("microcode", -1,
560							 NULL, 0);
561	if (IS_ERR(microcode_pdev))
562		return PTR_ERR(microcode_pdev);
563
564	get_online_cpus();
565	mutex_lock(&microcode_mutex);
566
567	error = subsys_interface_register(&mc_cpu_interface);
568	if (!error)
569		perf_check_microcode();
570	mutex_unlock(&microcode_mutex);
571	put_online_cpus();
572
573	if (error)
574		goto out_pdev;
575
576	error = sysfs_create_group(&cpu_subsys.dev_root->kobj,
577				   &cpu_root_microcode_group);
578
579	if (error) {
580		pr_err("Error creating microcode group!\n");
581		goto out_driver;
582	}
583
584	error = microcode_dev_init();
585	if (error)
586		goto out_ucode_group;
587
588	register_syscore_ops(&mc_syscore_ops);
589	register_hotcpu_notifier(&mc_cpu_notifier);
590
591	pr_info("Microcode Update Driver: v" MICROCODE_VERSION
592		" <tigran@aivazian.fsnet.co.uk>, Peter Oruba\n");
593
594	return 0;
595
596 out_ucode_group:
597	sysfs_remove_group(&cpu_subsys.dev_root->kobj,
598			   &cpu_root_microcode_group);
599
600 out_driver:
601	get_online_cpus();
602	mutex_lock(&microcode_mutex);
603
604	subsys_interface_unregister(&mc_cpu_interface);
605
606	mutex_unlock(&microcode_mutex);
607	put_online_cpus();
608
609 out_pdev:
610	platform_device_unregister(microcode_pdev);
611	return error;
612
613}
614module_init(microcode_init);
615
616static void __exit microcode_exit(void)
617{
618	struct cpuinfo_x86 *c = &cpu_data(0);
619
620	microcode_dev_exit();
621
622	unregister_hotcpu_notifier(&mc_cpu_notifier);
623	unregister_syscore_ops(&mc_syscore_ops);
624
625	sysfs_remove_group(&cpu_subsys.dev_root->kobj,
626			   &cpu_root_microcode_group);
627
628	get_online_cpus();
629	mutex_lock(&microcode_mutex);
630
631	subsys_interface_unregister(&mc_cpu_interface);
632
633	mutex_unlock(&microcode_mutex);
634	put_online_cpus();
635
636	platform_device_unregister(microcode_pdev);
637
638	microcode_ops = NULL;
639
640	if (c->x86_vendor == X86_VENDOR_AMD)
641		exit_amd_microcode();
642
643	pr_info("Microcode Update Driver: v" MICROCODE_VERSION " removed.\n");
644}
645module_exit(microcode_exit);