xref: /freebsd/sys/dev/efidev/efirt.c (revision 0957b409a90fd597c1e9124cbaf3edd2b488f4ac)
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, NULL, "EFI");
113 static bool efi_poweroff = true;
114 SYSCTL_BOOL(_hw_efi, OID_AUTO, poweroff, CTLFLAG_RWTUN, &efi_poweroff, 0,
115     "If true, use EFI runtime services to power off in preference to ACPI");
116 
117 static bool
118 efi_is_in_map(struct efi_md *map, int ndesc, int descsz, vm_offset_t addr)
119 {
120 	struct efi_md *p;
121 	int i;
122 
123 	for (i = 0, p = map; i < ndesc; i++, p = efi_next_descriptor(p,
124 	    descsz)) {
125 		if ((p->md_attr & EFI_MD_ATTR_RT) == 0)
126 			continue;
127 
128 		if (addr >= (uintptr_t)p->md_virt &&
129 		    addr < (uintptr_t)p->md_virt + p->md_pages * PAGE_SIZE)
130 			return (true);
131 	}
132 
133 	return (false);
134 }
135 
136 static void
137 efi_shutdown_final(void *dummy __unused, int howto)
138 {
139 
140 	/*
141 	 * On some systems, ACPI S5 is missing or does not function properly.
142 	 * When present, shutdown via EFI Runtime Services instead, unless
143 	 * disabled.
144 	 */
145 	if ((howto & RB_POWEROFF) != 0 && efi_poweroff)
146 		(void)efi_reset_system(EFI_RESET_SHUTDOWN);
147 }
148 
149 static int
150 efi_init(void)
151 {
152 	struct efi_map_header *efihdr;
153 	struct efi_md *map;
154 	struct efi_rt *rtdm;
155 	caddr_t kmdp;
156 	size_t efisz;
157 	int ndesc, rt_disabled;
158 
159 	rt_disabled = 0;
160 	TUNABLE_INT_FETCH("efi.rt.disabled", &rt_disabled);
161 	if (rt_disabled == 1)
162 		return (0);
163 	mtx_init(&efi_lock, "efi", NULL, MTX_DEF);
164 
165 	if (efi_systbl_phys == 0) {
166 		if (bootverbose)
167 			printf("EFI systbl not available\n");
168 		return (0);
169 	}
170 
171 	efi_systbl = (struct efi_systbl *)efi_phys_to_kva(efi_systbl_phys);
172 	if (efi_systbl == NULL || efi_systbl->st_hdr.th_sig != EFI_SYSTBL_SIG) {
173 		efi_systbl = NULL;
174 		if (bootverbose)
175 			printf("EFI systbl signature invalid\n");
176 		return (0);
177 	}
178 	efi_cfgtbl = (efi_systbl->st_cfgtbl == 0) ? NULL :
179 	    (struct efi_cfgtbl *)efi_systbl->st_cfgtbl;
180 	if (efi_cfgtbl == NULL) {
181 		if (bootverbose)
182 			printf("EFI config table is not present\n");
183 	}
184 
185 	kmdp = preload_search_by_type("elf kernel");
186 	if (kmdp == NULL)
187 		kmdp = preload_search_by_type("elf64 kernel");
188 	efihdr = (struct efi_map_header *)preload_search_info(kmdp,
189 	    MODINFO_METADATA | MODINFOMD_EFI_MAP);
190 	if (efihdr == NULL) {
191 		if (bootverbose)
192 			printf("EFI map is not present\n");
193 		return (0);
194 	}
195 	efisz = (sizeof(struct efi_map_header) + 0xf) & ~0xf;
196 	map = (struct efi_md *)((uint8_t *)efihdr + efisz);
197 	if (efihdr->descriptor_size == 0)
198 		return (ENOMEM);
199 
200 	ndesc = efihdr->memory_size / efihdr->descriptor_size;
201 	if (!efi_create_1t1_map(map, ndesc, efihdr->descriptor_size)) {
202 		if (bootverbose)
203 			printf("EFI cannot create runtime map\n");
204 		return (ENOMEM);
205 	}
206 
207 	efi_runtime = (efi_systbl->st_rt == 0) ? NULL :
208 	    (struct efi_rt *)efi_systbl->st_rt;
209 	if (efi_runtime == NULL) {
210 		if (bootverbose)
211 			printf("EFI runtime services table is not present\n");
212 		efi_destroy_1t1_map();
213 		return (ENXIO);
214 	}
215 
216 #if defined(__aarch64__) || defined(__amd64__)
217 	/*
218 	 * Some UEFI implementations have multiple implementations of the
219 	 * RS->GetTime function. They switch from one we can only use early
220 	 * in the boot process to one valid as a RunTime service only when we
221 	 * call RS->SetVirtualAddressMap. As this is not always the case, e.g.
222 	 * with an old loader.efi, check if the RS->GetTime function is within
223 	 * the EFI map, and fail to attach if not.
224 	 */
225 	rtdm = (struct efi_rt *)efi_phys_to_kva((uintptr_t)efi_runtime);
226 	if (rtdm == NULL || !efi_is_in_map(map, ndesc, efihdr->descriptor_size,
227 	    (vm_offset_t)rtdm->rt_gettime)) {
228 		if (bootverbose)
229 			printf(
230 			 "EFI runtime services table has an invalid pointer\n");
231 		efi_runtime = NULL;
232 		efi_destroy_1t1_map();
233 		return (ENXIO);
234 	}
235 #endif
236 
237 	/*
238 	 * We use SHUTDOWN_PRI_LAST - 1 to trigger after IPMI, but before ACPI.
239 	 */
240 	efi_shutdown_tag = EVENTHANDLER_REGISTER(shutdown_final,
241 	    efi_shutdown_final, NULL, SHUTDOWN_PRI_LAST - 1);
242 
243 	return (0);
244 }
245 
246 static void
247 efi_uninit(void)
248 {
249 
250 	/* Most likely disabled by tunable */
251 	if (efi_runtime == NULL)
252 		return;
253 	if (efi_shutdown_tag != NULL)
254 		EVENTHANDLER_DEREGISTER(shutdown_final, efi_shutdown_tag);
255 	efi_destroy_1t1_map();
256 
257 	efi_systbl = NULL;
258 	efi_cfgtbl = NULL;
259 	efi_runtime = NULL;
260 
261 	mtx_destroy(&efi_lock);
262 }
263 
264 int
265 efi_rt_ok(void)
266 {
267 
268 	if (efi_runtime == NULL)
269 		return (ENXIO);
270 	return (0);
271 }
272 
273 static int
274 efi_enter(void)
275 {
276 	struct thread *td;
277 	pmap_t curpmap;
278 
279 	if (efi_runtime == NULL)
280 		return (ENXIO);
281 	td = curthread;
282 	curpmap = &td->td_proc->p_vmspace->vm_pmap;
283 	PMAP_LOCK(curpmap);
284 	mtx_lock(&efi_lock);
285 	fpu_kern_enter(td, NULL, FPU_KERN_NOCTX);
286 	return (efi_arch_enter());
287 }
288 
289 static void
290 efi_leave(void)
291 {
292 	struct thread *td;
293 	pmap_t curpmap;
294 
295 	efi_arch_leave();
296 
297 	curpmap = &curproc->p_vmspace->vm_pmap;
298 	td = curthread;
299 	fpu_kern_leave(td, NULL);
300 	mtx_unlock(&efi_lock);
301 	PMAP_UNLOCK(curpmap);
302 }
303 
304 int
305 efi_get_table(struct uuid *uuid, void **ptr)
306 {
307 	struct efi_cfgtbl *ct;
308 	u_long count;
309 
310 	if (efi_cfgtbl == NULL || efi_systbl == NULL)
311 		return (ENXIO);
312 	count = efi_systbl->st_entries;
313 	ct = efi_cfgtbl;
314 	while (count--) {
315 		if (!bcmp(&ct->ct_uuid, uuid, sizeof(*uuid))) {
316 			*ptr = (void *)efi_phys_to_kva(ct->ct_data);
317 			return (0);
318 		}
319 		ct++;
320 	}
321 	return (ENOENT);
322 }
323 
324 static int efi_rt_handle_faults = EFI_RT_HANDLE_FAULTS_DEFAULT;
325 SYSCTL_INT(_machdep, OID_AUTO, efi_rt_handle_faults, CTLFLAG_RWTUN,
326     &efi_rt_handle_faults, 0,
327     "Call EFI RT methods with fault handler wrapper around");
328 
329 static int
330 efi_rt_arch_call_nofault(struct efirt_callinfo *ec)
331 {
332 
333 	switch (ec->ec_argcnt) {
334 	case 0:
335 		ec->ec_efi_status = ((register_t (*)(void))ec->ec_fptr)();
336 		break;
337 	case 1:
338 		ec->ec_efi_status = ((register_t (*)(register_t))ec->ec_fptr)
339 		    (ec->ec_arg1);
340 		break;
341 	case 2:
342 		ec->ec_efi_status = ((register_t (*)(register_t, register_t))
343 		    ec->ec_fptr)(ec->ec_arg1, ec->ec_arg2);
344 		break;
345 	case 3:
346 		ec->ec_efi_status = ((register_t (*)(register_t, register_t,
347 		    register_t))ec->ec_fptr)(ec->ec_arg1, ec->ec_arg2,
348 		    ec->ec_arg3);
349 		break;
350 	case 4:
351 		ec->ec_efi_status = ((register_t (*)(register_t, register_t,
352 		    register_t, register_t))ec->ec_fptr)(ec->ec_arg1,
353 		    ec->ec_arg2, ec->ec_arg3, ec->ec_arg4);
354 		break;
355 	case 5:
356 		ec->ec_efi_status = ((register_t (*)(register_t, register_t,
357 		    register_t, register_t, register_t))ec->ec_fptr)(
358 		    ec->ec_arg1, ec->ec_arg2, ec->ec_arg3, ec->ec_arg4,
359 		    ec->ec_arg5);
360 		break;
361 	default:
362 		panic("efi_rt_arch_call: %d args", (int)ec->ec_argcnt);
363 	}
364 
365 	return (0);
366 }
367 
368 static int
369 efi_call(struct efirt_callinfo *ecp)
370 {
371 	int error;
372 
373 	error = efi_enter();
374 	if (error != 0)
375 		return (error);
376 	error = efi_rt_handle_faults ? efi_rt_arch_call(ecp) :
377 	    efi_rt_arch_call_nofault(ecp);
378 	efi_leave();
379 	if (error == 0)
380 		error = efi_status_to_errno(ecp->ec_efi_status);
381 	else if (bootverbose)
382 		printf("EFI %s call faulted, error %d\n", ecp->ec_name, error);
383 	return (error);
384 }
385 
386 #define	EFI_RT_METHOD_PA(method)				\
387     ((uintptr_t)((struct efi_rt *)efi_phys_to_kva((uintptr_t)	\
388     efi_runtime))->method)
389 
390 static int
391 efi_get_time_locked(struct efi_tm *tm, struct efi_tmcap *tmcap)
392 {
393 	struct efirt_callinfo ec;
394 
395 	EFI_TIME_OWNED();
396 	if (efi_runtime == NULL)
397 		return (ENXIO);
398 	bzero(&ec, sizeof(ec));
399 	ec.ec_name = "rt_gettime";
400 	ec.ec_argcnt = 2;
401 	ec.ec_arg1 = (uintptr_t)tm;
402 	ec.ec_arg2 = (uintptr_t)tmcap;
403 	ec.ec_fptr = EFI_RT_METHOD_PA(rt_gettime);
404 	return (efi_call(&ec));
405 }
406 
407 int
408 efi_get_time(struct efi_tm *tm)
409 {
410 	struct efi_tmcap dummy;
411 	int error;
412 
413 	if (efi_runtime == NULL)
414 		return (ENXIO);
415 	EFI_TIME_LOCK();
416 	/*
417 	 * UEFI spec states that the Capabilities argument to GetTime is
418 	 * optional, but some UEFI implementations choke when passed a NULL
419 	 * pointer. Pass a dummy efi_tmcap, even though we won't use it,
420 	 * to workaround such implementations.
421 	 */
422 	error = efi_get_time_locked(tm, &dummy);
423 	EFI_TIME_UNLOCK();
424 	return (error);
425 }
426 
427 int
428 efi_get_time_capabilities(struct efi_tmcap *tmcap)
429 {
430 	struct efi_tm dummy;
431 	int error;
432 
433 	if (efi_runtime == NULL)
434 		return (ENXIO);
435 	EFI_TIME_LOCK();
436 	error = efi_get_time_locked(&dummy, tmcap);
437 	EFI_TIME_UNLOCK();
438 	return (error);
439 }
440 
441 int
442 efi_reset_system(enum efi_reset type)
443 {
444 	struct efirt_callinfo ec;
445 
446 	switch (type) {
447 	case EFI_RESET_COLD:
448 	case EFI_RESET_WARM:
449 	case EFI_RESET_SHUTDOWN:
450 		break;
451 	default:
452 		return (EINVAL);
453 	}
454 	if (efi_runtime == NULL)
455 		return (ENXIO);
456 	bzero(&ec, sizeof(ec));
457 	ec.ec_name = "rt_reset";
458 	ec.ec_argcnt = 4;
459 	ec.ec_arg1 = (uintptr_t)type;
460 	ec.ec_arg2 = (uintptr_t)0;
461 	ec.ec_arg3 = (uintptr_t)0;
462 	ec.ec_arg4 = (uintptr_t)NULL;
463 	ec.ec_fptr = EFI_RT_METHOD_PA(rt_reset);
464 	return (efi_call(&ec));
465 }
466 
467 static int
468 efi_set_time_locked(struct efi_tm *tm)
469 {
470 	struct efirt_callinfo ec;
471 
472 	EFI_TIME_OWNED();
473 	if (efi_runtime == NULL)
474 		return (ENXIO);
475 	bzero(&ec, sizeof(ec));
476 	ec.ec_name = "rt_settime";
477 	ec.ec_argcnt = 1;
478 	ec.ec_arg1 = (uintptr_t)tm;
479 	ec.ec_fptr = EFI_RT_METHOD_PA(rt_settime);
480 	return (efi_call(&ec));
481 }
482 
483 int
484 efi_set_time(struct efi_tm *tm)
485 {
486 	int error;
487 
488 	if (efi_runtime == NULL)
489 		return (ENXIO);
490 	EFI_TIME_LOCK();
491 	error = efi_set_time_locked(tm);
492 	EFI_TIME_UNLOCK();
493 	return (error);
494 }
495 
496 int
497 efi_var_get(efi_char *name, struct uuid *vendor, uint32_t *attrib,
498     size_t *datasize, void *data)
499 {
500 	struct efirt_callinfo ec;
501 
502 	if (efi_runtime == NULL)
503 		return (ENXIO);
504 	bzero(&ec, sizeof(ec));
505 	ec.ec_argcnt = 5;
506 	ec.ec_name = "rt_getvar";
507 	ec.ec_arg1 = (uintptr_t)name;
508 	ec.ec_arg2 = (uintptr_t)vendor;
509 	ec.ec_arg3 = (uintptr_t)attrib;
510 	ec.ec_arg4 = (uintptr_t)datasize;
511 	ec.ec_arg5 = (uintptr_t)data;
512 	ec.ec_fptr = EFI_RT_METHOD_PA(rt_getvar);
513 	return (efi_call(&ec));
514 }
515 
516 int
517 efi_var_nextname(size_t *namesize, efi_char *name, struct uuid *vendor)
518 {
519 	struct efirt_callinfo ec;
520 
521 	if (efi_runtime == NULL)
522 		return (ENXIO);
523 	bzero(&ec, sizeof(ec));
524 	ec.ec_argcnt = 3;
525 	ec.ec_name = "rt_scanvar";
526 	ec.ec_arg1 = (uintptr_t)namesize;
527 	ec.ec_arg2 = (uintptr_t)name;
528 	ec.ec_arg3 = (uintptr_t)vendor;
529 	ec.ec_fptr = EFI_RT_METHOD_PA(rt_scanvar);
530 	return (efi_call(&ec));
531 }
532 
533 int
534 efi_var_set(efi_char *name, struct uuid *vendor, uint32_t attrib,
535     size_t datasize, void *data)
536 {
537 	struct efirt_callinfo ec;
538 
539 	if (efi_runtime == NULL)
540 		return (ENXIO);
541 	bzero(&ec, sizeof(ec));
542 	ec.ec_argcnt = 5;
543 	ec.ec_name = "rt_setvar";
544 	ec.ec_arg1 = (uintptr_t)name;
545 	ec.ec_arg2 = (uintptr_t)vendor;
546 	ec.ec_arg3 = (uintptr_t)attrib;
547 	ec.ec_arg4 = (uintptr_t)datasize;
548 	ec.ec_arg5 = (uintptr_t)data;
549 	ec.ec_fptr = EFI_RT_METHOD_PA(rt_setvar);
550 	return (efi_call(&ec));
551 }
552 
553 static int
554 efirt_modevents(module_t m, int event, void *arg __unused)
555 {
556 
557 	switch (event) {
558 	case MOD_LOAD:
559 		return (efi_init());
560 
561 	case MOD_UNLOAD:
562 		efi_uninit();
563 		return (0);
564 
565 	case MOD_SHUTDOWN:
566 		return (0);
567 
568 	default:
569 		return (EOPNOTSUPP);
570 	}
571 }
572 
573 static moduledata_t efirt_moddata = {
574 	.name = "efirt",
575 	.evhand = efirt_modevents,
576 	.priv = NULL,
577 };
578 /* After fpuinitstate, before efidev */
579 DECLARE_MODULE(efirt, efirt_moddata, SI_SUB_DRIVERS, SI_ORDER_SECOND);
580 MODULE_VERSION(efirt, 1);
581