1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2006-2008 Stanislav Sedov <stas@FreeBSD.org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 */
29
30#include <sys/param.h>
31#include <sys/systm.h>
32#include <sys/conf.h>
33#include <sys/fcntl.h>
34#include <sys/ioccom.h>
35#include <sys/malloc.h>
36#include <sys/module.h>
37#include <sys/mutex.h>
38#include <sys/priv.h>
39#include <sys/proc.h>
40#include <sys/queue.h>
41#include <sys/sched.h>
42#include <sys/kernel.h>
43#include <sys/sysctl.h>
44#include <sys/uio.h>
45#include <sys/pcpu.h>
46#include <sys/smp.h>
47#include <sys/pmckern.h>
48#include <sys/cpuctl.h>
49
50#include <vm/vm.h>
51#include <vm/vm_param.h>
52#include <vm/pmap.h>
53
54#include <machine/cpufunc.h>
55#include <machine/md_var.h>
56#include <machine/specialreg.h>
57#include <x86/ucode.h>
58
59static d_open_t cpuctl_open;
60static d_ioctl_t cpuctl_ioctl;
61
62#define	CPUCTL_VERSION 1
63
64#ifdef CPUCTL_DEBUG
65# define	DPRINTF(format,...) printf(format, __VA_ARGS__);
66#else
67# define	DPRINTF(...)
68#endif
69
70#define	UCODE_SIZE_MAX	(4 * 1024 * 1024)
71
72static int cpuctl_do_msr(int cpu, cpuctl_msr_args_t *data, u_long cmd,
73    struct thread *td);
74static int cpuctl_do_cpuid(int cpu, cpuctl_cpuid_args_t *data,
75    struct thread *td);
76static int cpuctl_do_cpuid_count(int cpu, cpuctl_cpuid_count_args_t *data,
77    struct thread *td);
78static int cpuctl_do_eval_cpu_features(int cpu, struct thread *td);
79static int cpuctl_do_update(int cpu, cpuctl_update_args_t *data,
80    struct thread *td);
81static int update_intel(int cpu, cpuctl_update_args_t *args,
82    struct thread *td);
83static int update_amd(int cpu, cpuctl_update_args_t *args, struct thread *td);
84static int update_via(int cpu, cpuctl_update_args_t *args,
85    struct thread *td);
86
87static struct cdev **cpuctl_devs;
88static MALLOC_DEFINE(M_CPUCTL, "cpuctl", "CPUCTL buffer");
89
90static struct cdevsw cpuctl_cdevsw = {
91        .d_version =    D_VERSION,
92        .d_open =       cpuctl_open,
93        .d_ioctl =      cpuctl_ioctl,
94        .d_name =       "cpuctl",
95};
96
97/*
98 * This function checks if specified cpu enabled or not.
99 */
100static int
101cpu_enabled(int cpu)
102{
103
104	return (pmc_cpu_is_disabled(cpu) == 0);
105}
106
107/*
108 * Check if the current thread is bound to a specific cpu.
109 */
110static int
111cpu_sched_is_bound(struct thread *td)
112{
113	int ret;
114
115	thread_lock(td);
116	ret = sched_is_bound(td);
117	thread_unlock(td);
118	return (ret);
119}
120
121/*
122 * Switch to target cpu to run.
123 */
124static void
125set_cpu(int cpu, struct thread *td)
126{
127
128	KASSERT(cpu >= 0 && cpu <= mp_maxid && cpu_enabled(cpu),
129	    ("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu));
130	thread_lock(td);
131	sched_bind(td, cpu);
132	thread_unlock(td);
133	KASSERT(td->td_oncpu == cpu,
134	    ("[cpuctl,%d]: cannot bind to target cpu %d on cpu %d", __LINE__,
135	    cpu, td->td_oncpu));
136}
137
138static void
139restore_cpu(int oldcpu, int is_bound, struct thread *td)
140{
141
142	KASSERT(oldcpu >= 0 && oldcpu <= mp_maxid && cpu_enabled(oldcpu),
143	    ("[cpuctl,%d]: bad cpu number %d", __LINE__, oldcpu));
144	thread_lock(td);
145	if (is_bound == 0)
146		sched_unbind(td);
147	else
148		sched_bind(td, oldcpu);
149	thread_unlock(td);
150}
151
152int
153cpuctl_ioctl(struct cdev *dev, u_long cmd, caddr_t data,
154    int flags, struct thread *td)
155{
156	int cpu, ret;
157
158	cpu = dev2unit(dev);
159	if (cpu > mp_maxid || !cpu_enabled(cpu)) {
160		DPRINTF("[cpuctl,%d]: bad cpu number %d\n", __LINE__, cpu);
161		return (ENXIO);
162	}
163	/* Require write flag for "write" requests. */
164	if ((cmd == CPUCTL_MSRCBIT || cmd == CPUCTL_MSRSBIT ||
165	    cmd == CPUCTL_UPDATE || cmd == CPUCTL_WRMSR ||
166	    cmd == CPUCTL_EVAL_CPU_FEATURES) &&
167	    (flags & FWRITE) == 0)
168		return (EPERM);
169	switch (cmd) {
170	case CPUCTL_RDMSR:
171		ret = cpuctl_do_msr(cpu, (cpuctl_msr_args_t *)data, cmd, td);
172		break;
173	case CPUCTL_MSRSBIT:
174	case CPUCTL_MSRCBIT:
175	case CPUCTL_WRMSR:
176		ret = priv_check(td, PRIV_CPUCTL_WRMSR);
177		if (ret != 0)
178			goto fail;
179		ret = cpuctl_do_msr(cpu, (cpuctl_msr_args_t *)data, cmd, td);
180		break;
181	case CPUCTL_CPUID:
182		ret = cpuctl_do_cpuid(cpu, (cpuctl_cpuid_args_t *)data, td);
183		break;
184	case CPUCTL_UPDATE:
185		ret = priv_check(td, PRIV_CPUCTL_UPDATE);
186		if (ret != 0)
187			goto fail;
188		ret = cpuctl_do_update(cpu, (cpuctl_update_args_t *)data, td);
189		break;
190	case CPUCTL_CPUID_COUNT:
191		ret = cpuctl_do_cpuid_count(cpu,
192		    (cpuctl_cpuid_count_args_t *)data, td);
193		break;
194	case CPUCTL_EVAL_CPU_FEATURES:
195		ret = cpuctl_do_eval_cpu_features(cpu, td);
196		break;
197	default:
198		ret = EINVAL;
199		break;
200	}
201fail:
202	return (ret);
203}
204
205/*
206 * Actually perform cpuid operation.
207 */
208static int
209cpuctl_do_cpuid_count(int cpu, cpuctl_cpuid_count_args_t *data,
210    struct thread *td)
211{
212	int is_bound = 0;
213	int oldcpu;
214
215	KASSERT(cpu >= 0 && cpu <= mp_maxid,
216	    ("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu));
217
218	/* Explicitly clear cpuid data to avoid returning stale info. */
219	bzero(data->data, sizeof(data->data));
220	DPRINTF("[cpuctl,%d]: retrieving cpuid lev %#0x type %#0x for %d cpu\n",
221	    __LINE__, data->level, data->level_type, cpu);
222#ifdef __i386__
223	if (cpu_id == 0)
224		return (ENODEV);
225#endif
226	oldcpu = td->td_oncpu;
227	is_bound = cpu_sched_is_bound(td);
228	set_cpu(cpu, td);
229	cpuid_count(data->level, data->level_type, data->data);
230	restore_cpu(oldcpu, is_bound, td);
231	return (0);
232}
233
234static int
235cpuctl_do_cpuid(int cpu, cpuctl_cpuid_args_t *data, struct thread *td)
236{
237	cpuctl_cpuid_count_args_t cdata;
238	int error;
239
240	cdata.level = data->level;
241	/* Override the level type. */
242	cdata.level_type = 0;
243	error = cpuctl_do_cpuid_count(cpu, &cdata, td);
244	bcopy(cdata.data, data->data, sizeof(data->data)); /* Ignore error */
245	return (error);
246}
247
248/*
249 * Actually perform MSR operations.
250 */
251static int
252cpuctl_do_msr(int cpu, cpuctl_msr_args_t *data, u_long cmd, struct thread *td)
253{
254	uint64_t reg;
255	int is_bound = 0;
256	int oldcpu;
257	int ret;
258
259	KASSERT(cpu >= 0 && cpu <= mp_maxid,
260	    ("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu));
261
262	/*
263	 * Explicitly clear cpuid data to avoid returning stale
264	 * info
265	 */
266	DPRINTF("[cpuctl,%d]: operating on MSR %#0x for %d cpu\n", __LINE__,
267	    data->msr, cpu);
268#ifdef __i386__
269	if ((cpu_feature & CPUID_MSR) == 0)
270		return (ENODEV);
271#endif
272	oldcpu = td->td_oncpu;
273	is_bound = cpu_sched_is_bound(td);
274	set_cpu(cpu, td);
275	if (cmd == CPUCTL_RDMSR) {
276		data->data = 0;
277		ret = rdmsr_safe(data->msr, &data->data);
278	} else if (cmd == CPUCTL_WRMSR) {
279		ret = wrmsr_safe(data->msr, data->data);
280	} else if (cmd == CPUCTL_MSRSBIT) {
281		critical_enter();
282		ret = rdmsr_safe(data->msr, &reg);
283		if (ret == 0)
284			ret = wrmsr_safe(data->msr, reg | data->data);
285		critical_exit();
286	} else if (cmd == CPUCTL_MSRCBIT) {
287		critical_enter();
288		ret = rdmsr_safe(data->msr, &reg);
289		if (ret == 0)
290			ret = wrmsr_safe(data->msr, reg & ~data->data);
291		critical_exit();
292	} else
293		panic("[cpuctl,%d]: unknown operation requested: %lu",
294		    __LINE__, cmd);
295	restore_cpu(oldcpu, is_bound, td);
296	return (ret);
297}
298
299/*
300 * Actually perform microcode update.
301 */
302static int
303cpuctl_do_update(int cpu, cpuctl_update_args_t *data, struct thread *td)
304{
305	cpuctl_cpuid_args_t args = {
306		.level = 0,
307	};
308	char vendor[13];
309	int ret;
310
311	KASSERT(cpu >= 0 && cpu <= mp_maxid,
312	    ("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu));
313	DPRINTF("[cpuctl,%d]: XXX %d", __LINE__, cpu);
314
315	ret = cpuctl_do_cpuid(cpu, &args, td);
316	if (ret != 0)
317		return (ret);
318	((uint32_t *)vendor)[0] = args.data[1];
319	((uint32_t *)vendor)[1] = args.data[3];
320	((uint32_t *)vendor)[2] = args.data[2];
321	vendor[12] = '\0';
322	if (strncmp(vendor, INTEL_VENDOR_ID, sizeof(INTEL_VENDOR_ID)) == 0)
323		ret = update_intel(cpu, data, td);
324	else if(strncmp(vendor, AMD_VENDOR_ID, sizeof(AMD_VENDOR_ID)) == 0)
325		ret = update_amd(cpu, data, td);
326	else if(strncmp(vendor, CENTAUR_VENDOR_ID, sizeof(CENTAUR_VENDOR_ID))
327	    == 0)
328		ret = update_via(cpu, data, td);
329	else
330		ret = ENXIO;
331	return (ret);
332}
333
334struct ucode_update_data {
335	void *ptr;
336	int cpu;
337	int ret;
338};
339
340static void
341ucode_intel_load_rv(void *arg)
342{
343	struct ucode_update_data *d;
344
345	d = arg;
346	if (PCPU_GET(cpuid) == d->cpu)
347		d->ret = ucode_intel_load(d->ptr, true, NULL, NULL);
348}
349
350static int
351update_intel(int cpu, cpuctl_update_args_t *args, struct thread *td)
352{
353	struct ucode_update_data d;
354	void *ptr;
355	int is_bound, oldcpu, ret;
356
357	if (args->size == 0 || args->data == NULL) {
358		DPRINTF("[cpuctl,%d]: zero-sized firmware image", __LINE__);
359		return (EINVAL);
360	}
361	if (args->size > UCODE_SIZE_MAX) {
362		DPRINTF("[cpuctl,%d]: firmware image too large", __LINE__);
363		return (EINVAL);
364	}
365
366	/*
367	 * 16 byte alignment required.  Rely on the fact that
368	 * malloc(9) always returns the pointer aligned at least on
369	 * the size of the allocation.
370	 */
371	ptr = malloc(args->size + 16, M_CPUCTL, M_WAITOK);
372	if (copyin(args->data, ptr, args->size) != 0) {
373		DPRINTF("[cpuctl,%d]: copyin %p->%p of %zd bytes failed",
374		    __LINE__, args->data, ptr, args->size);
375		ret = EFAULT;
376		goto out;
377	}
378	oldcpu = td->td_oncpu;
379	is_bound = cpu_sched_is_bound(td);
380	set_cpu(cpu, td);
381	d.ptr = ptr;
382	d.cpu = cpu;
383	smp_rendezvous(NULL, ucode_intel_load_rv, NULL, &d);
384	restore_cpu(oldcpu, is_bound, td);
385	ret = d.ret;
386
387	/*
388	 * Replace any existing update.  This ensures that the new update
389	 * will be reloaded automatically during ACPI resume.
390	 */
391	if (ret == 0)
392		ptr = ucode_update(ptr);
393
394out:
395	free(ptr, M_CPUCTL);
396	return (ret);
397}
398
399/*
400 * NB: MSR 0xc0010020, MSR_K8_UCODE_UPDATE, is not documented by AMD.
401 * Coreboot, illumos and Linux source code was used to understand
402 * its workings.
403 */
404static void
405amd_ucode_wrmsr(void *ucode_ptr)
406{
407	uint32_t tmp[4];
408
409	wrmsr_safe(MSR_K8_UCODE_UPDATE, (uintptr_t)ucode_ptr);
410	do_cpuid(0, tmp);
411}
412
413static int
414update_amd(int cpu, cpuctl_update_args_t *args, struct thread *td)
415{
416	void *ptr;
417	int ret;
418
419	if (args->size == 0 || args->data == NULL) {
420		DPRINTF("[cpuctl,%d]: zero-sized firmware image", __LINE__);
421		return (EINVAL);
422	}
423	if (args->size > UCODE_SIZE_MAX) {
424		DPRINTF("[cpuctl,%d]: firmware image too large", __LINE__);
425		return (EINVAL);
426	}
427
428	/*
429	 * 16 byte alignment required.  Rely on the fact that
430	 * malloc(9) always returns the pointer aligned at least on
431	 * the size of the allocation.
432	 */
433	ptr = malloc(args->size + 16, M_CPUCTL, M_ZERO | M_WAITOK);
434	if (copyin(args->data, ptr, args->size) != 0) {
435		DPRINTF("[cpuctl,%d]: copyin %p->%p of %zd bytes failed",
436		    __LINE__, args->data, ptr, args->size);
437		ret = EFAULT;
438		goto fail;
439	}
440	smp_rendezvous(NULL, amd_ucode_wrmsr, NULL, ptr);
441	ret = 0;
442fail:
443	free(ptr, M_CPUCTL);
444	return (ret);
445}
446
447static int
448update_via(int cpu, cpuctl_update_args_t *args, struct thread *td)
449{
450	void *ptr;
451	uint64_t rev0, rev1, res;
452	uint32_t tmp[4];
453	int is_bound;
454	int oldcpu;
455	int ret;
456
457	if (args->size == 0 || args->data == NULL) {
458		DPRINTF("[cpuctl,%d]: zero-sized firmware image", __LINE__);
459		return (EINVAL);
460	}
461	if (args->size > UCODE_SIZE_MAX) {
462		DPRINTF("[cpuctl,%d]: firmware image too large", __LINE__);
463		return (EINVAL);
464	}
465
466	/*
467	 * 4 byte alignment required.
468	 */
469	ptr = malloc(args->size, M_CPUCTL, M_WAITOK);
470	if (copyin(args->data, ptr, args->size) != 0) {
471		DPRINTF("[cpuctl,%d]: copyin %p->%p of %zd bytes failed",
472		    __LINE__, args->data, ptr, args->size);
473		ret = EFAULT;
474		goto fail;
475	}
476	oldcpu = td->td_oncpu;
477	is_bound = cpu_sched_is_bound(td);
478	set_cpu(cpu, td);
479	critical_enter();
480	rdmsr_safe(MSR_BIOS_SIGN, &rev0); /* Get current microcode revision. */
481
482	/*
483	 * Perform update.
484	 */
485	wrmsr_safe(MSR_BIOS_UPDT_TRIG, (uintptr_t)(ptr));
486	do_cpuid(1, tmp);
487
488	/*
489	 * Result are in low byte of MSR FCR5:
490	 * 0x00: No update has been attempted since RESET.
491	 * 0x01: The last attempted update was successful.
492	 * 0x02: The last attempted update was unsuccessful due to a bad
493	 *       environment. No update was loaded and any preexisting
494	 *       patches are still active.
495	 * 0x03: The last attempted update was not applicable to this processor.
496	 *       No update was loaded and any preexisting patches are still
497	 *       active.
498	 * 0x04: The last attempted update was not successful due to an invalid
499	 *       update data block. No update was loaded and any preexisting
500	 *       patches are still active
501	 */
502	rdmsr_safe(0x1205, &res);
503	res &= 0xff;
504	critical_exit();
505	rdmsr_safe(MSR_BIOS_SIGN, &rev1); /* Get new microcode revision. */
506	restore_cpu(oldcpu, is_bound, td);
507
508	DPRINTF("[cpu,%d]: rev0=%x rev1=%x res=%x\n", __LINE__,
509	    (unsigned)(rev0 >> 32), (unsigned)(rev1 >> 32), (unsigned)res);
510
511	if (res != 0x01)
512		ret = EINVAL;
513	else
514		ret = 0;
515fail:
516	free(ptr, M_CPUCTL);
517	return (ret);
518}
519
520static int
521cpuctl_do_eval_cpu_features(int cpu, struct thread *td)
522{
523	int is_bound = 0;
524	int oldcpu;
525
526	KASSERT(cpu >= 0 && cpu <= mp_maxid,
527	    ("[cpuctl,%d]: bad cpu number %d", __LINE__, cpu));
528
529#ifdef __i386__
530	if (cpu_id == 0)
531		return (ENODEV);
532#endif
533	oldcpu = td->td_oncpu;
534	is_bound = cpu_sched_is_bound(td);
535	set_cpu(cpu, td);
536	identify_cpu1();
537	identify_cpu2();
538	restore_cpu(oldcpu, is_bound, td);
539	hw_ibrs_recalculate(true);
540	hw_ssb_recalculate(true);
541#ifdef __amd64__
542	amd64_syscall_ret_flush_l1d_recalc();
543	pmap_allow_2m_x_ept_recalculate();
544#endif
545	hw_mds_recalculate();
546	x86_taa_recalculate();
547	x86_rngds_mitg_recalculate(true);
548	zenbleed_check_and_apply(true);
549	printcpuinfo();
550	return (0);
551}
552
553int
554cpuctl_open(struct cdev *dev, int flags, int fmt __unused, struct thread *td)
555{
556	int ret = 0;
557	int cpu;
558
559	cpu = dev2unit(dev);
560	if (cpu > mp_maxid || !cpu_enabled(cpu)) {
561		DPRINTF("[cpuctl,%d]: incorrect cpu number %d\n", __LINE__,
562		    cpu);
563		return (ENXIO);
564	}
565	if (flags & FWRITE)
566		ret = securelevel_gt(td->td_ucred, 0);
567	return (ret);
568}
569
570static int
571cpuctl_modevent(module_t mod __unused, int type, void *data __unused)
572{
573	int cpu;
574
575	switch(type) {
576	case MOD_LOAD:
577		if (bootverbose)
578			printf("cpuctl: access to MSR registers/cpuid info.\n");
579		cpuctl_devs = malloc(sizeof(*cpuctl_devs) * (mp_maxid + 1), M_CPUCTL,
580		    M_WAITOK | M_ZERO);
581		CPU_FOREACH(cpu)
582			if (cpu_enabled(cpu))
583				cpuctl_devs[cpu] = make_dev(&cpuctl_cdevsw, cpu,
584				    UID_ROOT, GID_KMEM, 0640, "cpuctl%d", cpu);
585		break;
586	case MOD_UNLOAD:
587		CPU_FOREACH(cpu) {
588			if (cpuctl_devs[cpu] != NULL)
589				destroy_dev(cpuctl_devs[cpu]);
590		}
591		free(cpuctl_devs, M_CPUCTL);
592		break;
593	case MOD_SHUTDOWN:
594		break;
595	default:
596		return (EOPNOTSUPP);
597        }
598	return (0);
599}
600
601DEV_MODULE(cpuctl, cpuctl_modevent, NULL);
602MODULE_VERSION(cpuctl, CPUCTL_VERSION);
603