xref: /freebsd/sys/dev/efidev/efirt.c (revision e17f5b1d307b7b8910d67883e57a9604305906d5)
1 /*-
2  * Copyright (c) 2004 Marcel Moolenaar
3  * Copyright (c) 2001 Doug Rabson
4  * Copyright (c) 2016, 2018 The FreeBSD Foundation
5  * All rights reserved.
6  *
7  * Portions of this software were developed by Konstantin Belousov
8  * under sponsorship from the FreeBSD Foundation.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #include <sys/param.h>
36 #include <sys/efi.h>
37 #include <sys/eventhandler.h>
38 #include <sys/kernel.h>
39 #include <sys/linker.h>
40 #include <sys/lock.h>
41 #include <sys/module.h>
42 #include <sys/mutex.h>
43 #include <sys/clock.h>
44 #include <sys/proc.h>
45 #include <sys/reboot.h>
46 #include <sys/rwlock.h>
47 #include <sys/sched.h>
48 #include <sys/sysctl.h>
49 #include <sys/systm.h>
50 #include <sys/vmmeter.h>
51 
52 #include <machine/fpu.h>
53 #include <machine/efi.h>
54 #include <machine/metadata.h>
55 #include <machine/vmparam.h>
56 
57 #include <vm/vm.h>
58 #include <vm/pmap.h>
59 #include <vm/vm_map.h>
60 
61 static struct efi_systbl *efi_systbl;
62 static eventhandler_tag efi_shutdown_tag;
63 /*
64  * The following pointers point to tables in the EFI runtime service data pages.
65  * Care should be taken to make sure that we've properly entered the EFI runtime
66  * environment (efi_enter()) before dereferencing them.
67  */
68 static struct efi_cfgtbl *efi_cfgtbl;
69 static struct efi_rt *efi_runtime;
70 
71 static int efi_status2err[25] = {
72 	0,		/* EFI_SUCCESS */
73 	ENOEXEC,	/* EFI_LOAD_ERROR */
74 	EINVAL,		/* EFI_INVALID_PARAMETER */
75 	ENOSYS,		/* EFI_UNSUPPORTED */
76 	EMSGSIZE, 	/* EFI_BAD_BUFFER_SIZE */
77 	EOVERFLOW,	/* EFI_BUFFER_TOO_SMALL */
78 	EBUSY,		/* EFI_NOT_READY */
79 	EIO,		/* EFI_DEVICE_ERROR */
80 	EROFS,		/* EFI_WRITE_PROTECTED */
81 	EAGAIN,		/* EFI_OUT_OF_RESOURCES */
82 	EIO,		/* EFI_VOLUME_CORRUPTED */
83 	ENOSPC,		/* EFI_VOLUME_FULL */
84 	ENXIO,		/* EFI_NO_MEDIA */
85 	ESTALE,		/* EFI_MEDIA_CHANGED */
86 	ENOENT,		/* EFI_NOT_FOUND */
87 	EACCES,		/* EFI_ACCESS_DENIED */
88 	ETIMEDOUT,	/* EFI_NO_RESPONSE */
89 	EADDRNOTAVAIL,	/* EFI_NO_MAPPING */
90 	ETIMEDOUT,	/* EFI_TIMEOUT */
91 	EDOOFUS,	/* EFI_NOT_STARTED */
92 	EALREADY,	/* EFI_ALREADY_STARTED */
93 	ECANCELED,	/* EFI_ABORTED */
94 	EPROTO,		/* EFI_ICMP_ERROR */
95 	EPROTO,		/* EFI_TFTP_ERROR */
96 	EPROTO		/* EFI_PROTOCOL_ERROR */
97 };
98 
99 static int efi_enter(void);
100 static void efi_leave(void);
101 
102 static int
103 efi_status_to_errno(efi_status status)
104 {
105 	u_long code;
106 
107 	code = status & 0x3ffffffffffffffful;
108 	return (code < nitems(efi_status2err) ? efi_status2err[code] : EDOOFUS);
109 }
110 
111 static struct mtx efi_lock;
112 static SYSCTL_NODE(_hw, OID_AUTO, efi, CTLFLAG_RWTUN | CTLFLAG_MPSAFE, NULL,
113     "EFI");
114 static bool efi_poweroff = true;
115 SYSCTL_BOOL(_hw_efi, OID_AUTO, poweroff, CTLFLAG_RWTUN, &efi_poweroff, 0,
116     "If true, use EFI runtime services to power off in preference to ACPI");
117 
118 static bool
119 efi_is_in_map(struct efi_md *map, int ndesc, int descsz, vm_offset_t addr)
120 {
121 	struct efi_md *p;
122 	int i;
123 
124 	for (i = 0, p = map; i < ndesc; i++, p = efi_next_descriptor(p,
125 	    descsz)) {
126 		if ((p->md_attr & EFI_MD_ATTR_RT) == 0)
127 			continue;
128 
129 		if (addr >= (uintptr_t)p->md_virt &&
130 		    addr < (uintptr_t)p->md_virt + p->md_pages * PAGE_SIZE)
131 			return (true);
132 	}
133 
134 	return (false);
135 }
136 
137 static void
138 efi_shutdown_final(void *dummy __unused, int howto)
139 {
140 
141 	/*
142 	 * On some systems, ACPI S5 is missing or does not function properly.
143 	 * When present, shutdown via EFI Runtime Services instead, unless
144 	 * disabled.
145 	 */
146 	if ((howto & RB_POWEROFF) != 0 && efi_poweroff)
147 		(void)efi_reset_system(EFI_RESET_SHUTDOWN);
148 }
149 
150 static int
151 efi_init(void)
152 {
153 	struct efi_map_header *efihdr;
154 	struct efi_md *map;
155 	struct efi_rt *rtdm;
156 	caddr_t kmdp;
157 	size_t efisz;
158 	int ndesc, rt_disabled;
159 
160 	rt_disabled = 0;
161 	TUNABLE_INT_FETCH("efi.rt.disabled", &rt_disabled);
162 	if (rt_disabled == 1)
163 		return (0);
164 	mtx_init(&efi_lock, "efi", NULL, MTX_DEF);
165 
166 	if (efi_systbl_phys == 0) {
167 		if (bootverbose)
168 			printf("EFI systbl not available\n");
169 		return (0);
170 	}
171 
172 	efi_systbl = (struct efi_systbl *)efi_phys_to_kva(efi_systbl_phys);
173 	if (efi_systbl == NULL || efi_systbl->st_hdr.th_sig != EFI_SYSTBL_SIG) {
174 		efi_systbl = NULL;
175 		if (bootverbose)
176 			printf("EFI systbl signature invalid\n");
177 		return (0);
178 	}
179 	efi_cfgtbl = (efi_systbl->st_cfgtbl == 0) ? NULL :
180 	    (struct efi_cfgtbl *)efi_systbl->st_cfgtbl;
181 	if (efi_cfgtbl == NULL) {
182 		if (bootverbose)
183 			printf("EFI config table is not present\n");
184 	}
185 
186 	kmdp = preload_search_by_type("elf kernel");
187 	if (kmdp == NULL)
188 		kmdp = preload_search_by_type("elf64 kernel");
189 	efihdr = (struct efi_map_header *)preload_search_info(kmdp,
190 	    MODINFO_METADATA | MODINFOMD_EFI_MAP);
191 	if (efihdr == NULL) {
192 		if (bootverbose)
193 			printf("EFI map is not present\n");
194 		return (0);
195 	}
196 	efisz = (sizeof(struct efi_map_header) + 0xf) & ~0xf;
197 	map = (struct efi_md *)((uint8_t *)efihdr + efisz);
198 	if (efihdr->descriptor_size == 0)
199 		return (ENOMEM);
200 
201 	ndesc = efihdr->memory_size / efihdr->descriptor_size;
202 	if (!efi_create_1t1_map(map, ndesc, efihdr->descriptor_size)) {
203 		if (bootverbose)
204 			printf("EFI cannot create runtime map\n");
205 		return (ENOMEM);
206 	}
207 
208 	efi_runtime = (efi_systbl->st_rt == 0) ? NULL :
209 	    (struct efi_rt *)efi_systbl->st_rt;
210 	if (efi_runtime == NULL) {
211 		if (bootverbose)
212 			printf("EFI runtime services table is not present\n");
213 		efi_destroy_1t1_map();
214 		return (ENXIO);
215 	}
216 
217 #if defined(__aarch64__) || defined(__amd64__)
218 	/*
219 	 * Some UEFI implementations have multiple implementations of the
220 	 * RS->GetTime function. They switch from one we can only use early
221 	 * in the boot process to one valid as a RunTime service only when we
222 	 * call RS->SetVirtualAddressMap. As this is not always the case, e.g.
223 	 * with an old loader.efi, check if the RS->GetTime function is within
224 	 * the EFI map, and fail to attach if not.
225 	 */
226 	rtdm = (struct efi_rt *)efi_phys_to_kva((uintptr_t)efi_runtime);
227 	if (rtdm == NULL || !efi_is_in_map(map, ndesc, efihdr->descriptor_size,
228 	    (vm_offset_t)rtdm->rt_gettime)) {
229 		if (bootverbose)
230 			printf(
231 			 "EFI runtime services table has an invalid pointer\n");
232 		efi_runtime = NULL;
233 		efi_destroy_1t1_map();
234 		return (ENXIO);
235 	}
236 #endif
237 
238 	/*
239 	 * We use SHUTDOWN_PRI_LAST - 1 to trigger after IPMI, but before ACPI.
240 	 */
241 	efi_shutdown_tag = EVENTHANDLER_REGISTER(shutdown_final,
242 	    efi_shutdown_final, NULL, SHUTDOWN_PRI_LAST - 1);
243 
244 	return (0);
245 }
246 
247 static void
248 efi_uninit(void)
249 {
250 
251 	/* Most likely disabled by tunable */
252 	if (efi_runtime == NULL)
253 		return;
254 	if (efi_shutdown_tag != NULL)
255 		EVENTHANDLER_DEREGISTER(shutdown_final, efi_shutdown_tag);
256 	efi_destroy_1t1_map();
257 
258 	efi_systbl = NULL;
259 	efi_cfgtbl = NULL;
260 	efi_runtime = NULL;
261 
262 	mtx_destroy(&efi_lock);
263 }
264 
265 int
266 efi_rt_ok(void)
267 {
268 
269 	if (efi_runtime == NULL)
270 		return (ENXIO);
271 	return (0);
272 }
273 
274 static int
275 efi_enter(void)
276 {
277 	struct thread *td;
278 	pmap_t curpmap;
279 	int error;
280 
281 	if (efi_runtime == NULL)
282 		return (ENXIO);
283 	td = curthread;
284 	curpmap = &td->td_proc->p_vmspace->vm_pmap;
285 	PMAP_LOCK(curpmap);
286 	mtx_lock(&efi_lock);
287 	fpu_kern_enter(td, NULL, FPU_KERN_NOCTX);
288 	error = efi_arch_enter();
289 	if (error != 0) {
290 		fpu_kern_leave(td, NULL);
291 		mtx_unlock(&efi_lock);
292 		PMAP_UNLOCK(curpmap);
293 	}
294 	return (error);
295 }
296 
297 static void
298 efi_leave(void)
299 {
300 	struct thread *td;
301 	pmap_t curpmap;
302 
303 	efi_arch_leave();
304 
305 	curpmap = &curproc->p_vmspace->vm_pmap;
306 	td = curthread;
307 	fpu_kern_leave(td, NULL);
308 	mtx_unlock(&efi_lock);
309 	PMAP_UNLOCK(curpmap);
310 }
311 
312 int
313 efi_get_table(struct uuid *uuid, void **ptr)
314 {
315 	struct efi_cfgtbl *ct;
316 	u_long count;
317 
318 	if (efi_cfgtbl == NULL || efi_systbl == NULL)
319 		return (ENXIO);
320 	count = efi_systbl->st_entries;
321 	ct = efi_cfgtbl;
322 	while (count--) {
323 		if (!bcmp(&ct->ct_uuid, uuid, sizeof(*uuid))) {
324 			*ptr = (void *)efi_phys_to_kva(ct->ct_data);
325 			return (0);
326 		}
327 		ct++;
328 	}
329 	return (ENOENT);
330 }
331 
332 static int efi_rt_handle_faults = EFI_RT_HANDLE_FAULTS_DEFAULT;
333 SYSCTL_INT(_machdep, OID_AUTO, efi_rt_handle_faults, CTLFLAG_RWTUN,
334     &efi_rt_handle_faults, 0,
335     "Call EFI RT methods with fault handler wrapper around");
336 
337 static int
338 efi_rt_arch_call_nofault(struct efirt_callinfo *ec)
339 {
340 
341 	switch (ec->ec_argcnt) {
342 	case 0:
343 		ec->ec_efi_status = ((register_t (*)(void))ec->ec_fptr)();
344 		break;
345 	case 1:
346 		ec->ec_efi_status = ((register_t (*)(register_t))ec->ec_fptr)
347 		    (ec->ec_arg1);
348 		break;
349 	case 2:
350 		ec->ec_efi_status = ((register_t (*)(register_t, register_t))
351 		    ec->ec_fptr)(ec->ec_arg1, ec->ec_arg2);
352 		break;
353 	case 3:
354 		ec->ec_efi_status = ((register_t (*)(register_t, register_t,
355 		    register_t))ec->ec_fptr)(ec->ec_arg1, ec->ec_arg2,
356 		    ec->ec_arg3);
357 		break;
358 	case 4:
359 		ec->ec_efi_status = ((register_t (*)(register_t, register_t,
360 		    register_t, register_t))ec->ec_fptr)(ec->ec_arg1,
361 		    ec->ec_arg2, ec->ec_arg3, ec->ec_arg4);
362 		break;
363 	case 5:
364 		ec->ec_efi_status = ((register_t (*)(register_t, register_t,
365 		    register_t, register_t, register_t))ec->ec_fptr)(
366 		    ec->ec_arg1, ec->ec_arg2, ec->ec_arg3, ec->ec_arg4,
367 		    ec->ec_arg5);
368 		break;
369 	default:
370 		panic("efi_rt_arch_call: %d args", (int)ec->ec_argcnt);
371 	}
372 
373 	return (0);
374 }
375 
376 static int
377 efi_call(struct efirt_callinfo *ecp)
378 {
379 	int error;
380 
381 	error = efi_enter();
382 	if (error != 0)
383 		return (error);
384 	error = efi_rt_handle_faults ? efi_rt_arch_call(ecp) :
385 	    efi_rt_arch_call_nofault(ecp);
386 	efi_leave();
387 	if (error == 0)
388 		error = efi_status_to_errno(ecp->ec_efi_status);
389 	else if (bootverbose)
390 		printf("EFI %s call faulted, error %d\n", ecp->ec_name, error);
391 	return (error);
392 }
393 
394 #define	EFI_RT_METHOD_PA(method)				\
395     ((uintptr_t)((struct efi_rt *)efi_phys_to_kva((uintptr_t)	\
396     efi_runtime))->method)
397 
398 static int
399 efi_get_time_locked(struct efi_tm *tm, struct efi_tmcap *tmcap)
400 {
401 	struct efirt_callinfo ec;
402 
403 	EFI_TIME_OWNED();
404 	if (efi_runtime == NULL)
405 		return (ENXIO);
406 	bzero(&ec, sizeof(ec));
407 	ec.ec_name = "rt_gettime";
408 	ec.ec_argcnt = 2;
409 	ec.ec_arg1 = (uintptr_t)tm;
410 	ec.ec_arg2 = (uintptr_t)tmcap;
411 	ec.ec_fptr = EFI_RT_METHOD_PA(rt_gettime);
412 	return (efi_call(&ec));
413 }
414 
415 int
416 efi_get_time(struct efi_tm *tm)
417 {
418 	struct efi_tmcap dummy;
419 	int error;
420 
421 	if (efi_runtime == NULL)
422 		return (ENXIO);
423 	EFI_TIME_LOCK();
424 	/*
425 	 * UEFI spec states that the Capabilities argument to GetTime is
426 	 * optional, but some UEFI implementations choke when passed a NULL
427 	 * pointer. Pass a dummy efi_tmcap, even though we won't use it,
428 	 * to workaround such implementations.
429 	 */
430 	error = efi_get_time_locked(tm, &dummy);
431 	EFI_TIME_UNLOCK();
432 	return (error);
433 }
434 
435 int
436 efi_get_time_capabilities(struct efi_tmcap *tmcap)
437 {
438 	struct efi_tm dummy;
439 	int error;
440 
441 	if (efi_runtime == NULL)
442 		return (ENXIO);
443 	EFI_TIME_LOCK();
444 	error = efi_get_time_locked(&dummy, tmcap);
445 	EFI_TIME_UNLOCK();
446 	return (error);
447 }
448 
449 int
450 efi_reset_system(enum efi_reset type)
451 {
452 	struct efirt_callinfo ec;
453 
454 	switch (type) {
455 	case EFI_RESET_COLD:
456 	case EFI_RESET_WARM:
457 	case EFI_RESET_SHUTDOWN:
458 		break;
459 	default:
460 		return (EINVAL);
461 	}
462 	if (efi_runtime == NULL)
463 		return (ENXIO);
464 	bzero(&ec, sizeof(ec));
465 	ec.ec_name = "rt_reset";
466 	ec.ec_argcnt = 4;
467 	ec.ec_arg1 = (uintptr_t)type;
468 	ec.ec_arg2 = (uintptr_t)0;
469 	ec.ec_arg3 = (uintptr_t)0;
470 	ec.ec_arg4 = (uintptr_t)NULL;
471 	ec.ec_fptr = EFI_RT_METHOD_PA(rt_reset);
472 	return (efi_call(&ec));
473 }
474 
475 static int
476 efi_set_time_locked(struct efi_tm *tm)
477 {
478 	struct efirt_callinfo ec;
479 
480 	EFI_TIME_OWNED();
481 	if (efi_runtime == NULL)
482 		return (ENXIO);
483 	bzero(&ec, sizeof(ec));
484 	ec.ec_name = "rt_settime";
485 	ec.ec_argcnt = 1;
486 	ec.ec_arg1 = (uintptr_t)tm;
487 	ec.ec_fptr = EFI_RT_METHOD_PA(rt_settime);
488 	return (efi_call(&ec));
489 }
490 
491 int
492 efi_set_time(struct efi_tm *tm)
493 {
494 	int error;
495 
496 	if (efi_runtime == NULL)
497 		return (ENXIO);
498 	EFI_TIME_LOCK();
499 	error = efi_set_time_locked(tm);
500 	EFI_TIME_UNLOCK();
501 	return (error);
502 }
503 
504 int
505 efi_var_get(efi_char *name, struct uuid *vendor, uint32_t *attrib,
506     size_t *datasize, void *data)
507 {
508 	struct efirt_callinfo ec;
509 
510 	if (efi_runtime == NULL)
511 		return (ENXIO);
512 	bzero(&ec, sizeof(ec));
513 	ec.ec_argcnt = 5;
514 	ec.ec_name = "rt_getvar";
515 	ec.ec_arg1 = (uintptr_t)name;
516 	ec.ec_arg2 = (uintptr_t)vendor;
517 	ec.ec_arg3 = (uintptr_t)attrib;
518 	ec.ec_arg4 = (uintptr_t)datasize;
519 	ec.ec_arg5 = (uintptr_t)data;
520 	ec.ec_fptr = EFI_RT_METHOD_PA(rt_getvar);
521 	return (efi_call(&ec));
522 }
523 
524 int
525 efi_var_nextname(size_t *namesize, efi_char *name, struct uuid *vendor)
526 {
527 	struct efirt_callinfo ec;
528 
529 	if (efi_runtime == NULL)
530 		return (ENXIO);
531 	bzero(&ec, sizeof(ec));
532 	ec.ec_argcnt = 3;
533 	ec.ec_name = "rt_scanvar";
534 	ec.ec_arg1 = (uintptr_t)namesize;
535 	ec.ec_arg2 = (uintptr_t)name;
536 	ec.ec_arg3 = (uintptr_t)vendor;
537 	ec.ec_fptr = EFI_RT_METHOD_PA(rt_scanvar);
538 	return (efi_call(&ec));
539 }
540 
541 int
542 efi_var_set(efi_char *name, struct uuid *vendor, uint32_t attrib,
543     size_t datasize, void *data)
544 {
545 	struct efirt_callinfo ec;
546 
547 	if (efi_runtime == NULL)
548 		return (ENXIO);
549 	bzero(&ec, sizeof(ec));
550 	ec.ec_argcnt = 5;
551 	ec.ec_name = "rt_setvar";
552 	ec.ec_arg1 = (uintptr_t)name;
553 	ec.ec_arg2 = (uintptr_t)vendor;
554 	ec.ec_arg3 = (uintptr_t)attrib;
555 	ec.ec_arg4 = (uintptr_t)datasize;
556 	ec.ec_arg5 = (uintptr_t)data;
557 	ec.ec_fptr = EFI_RT_METHOD_PA(rt_setvar);
558 	return (efi_call(&ec));
559 }
560 
561 static int
562 efirt_modevents(module_t m, int event, void *arg __unused)
563 {
564 
565 	switch (event) {
566 	case MOD_LOAD:
567 		return (efi_init());
568 
569 	case MOD_UNLOAD:
570 		efi_uninit();
571 		return (0);
572 
573 	case MOD_SHUTDOWN:
574 		return (0);
575 
576 	default:
577 		return (EOPNOTSUPP);
578 	}
579 }
580 
581 static moduledata_t efirt_moddata = {
582 	.name = "efirt",
583 	.evhand = efirt_modevents,
584 	.priv = NULL,
585 };
586 /* After fpuinitstate, before efidev */
587 DECLARE_MODULE(efirt, efirt_moddata, SI_SUB_DRIVERS, SI_ORDER_SECOND);
588 MODULE_VERSION(efirt, 1);
589