xref: /dragonfly/sys/platform/pc64/x86_64/efirt.c (revision 7d89978d)
1 /*-
2  * Copyright (c) 2004 Marcel Moolenaar
3  * Copyright (c) 2001 Doug Rabson
4  * Copyright (c) 2016 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  * $FreeBSD: head/sys/amd64/amd64/efirt.c 307391 2016-10-16 06:07:43Z kib $
32  */
33 
34 #include <sys/param.h>
35 #include <sys/efi.h>
36 #include <sys/kernel.h>
37 #include <sys/linker.h>
38 #include <sys/lock.h>
39 #include <sys/malloc.h>
40 #include <sys/module.h>
41 #include <sys/proc.h>
42 #include <sys/sched.h>
43 #include <sys/sysctl.h>
44 #include <sys/systm.h>
45 #include <sys/thread.h>
46 #include <sys/globaldata.h>
47 
48 #include <vm/vm.h>
49 #include <vm/pmap.h>
50 #include <vm/vm_map.h>
51 #include <vm/vm_object.h>
52 #include <vm/vm_param.h>
53 #include <vm/vm_page.h>
54 #include <vm/vm_pager.h>
55 #include <vm/vm_extern.h>
56 
57 #include <vm/vm_page2.h>
58 
59 #include <machine/efi.h>
60 #include <machine/metadata.h>
61 #include <machine/md_var.h>
62 #include <machine/smp.h>
63 #include <machine/vmparam.h>
64 
65 static struct efi_systbl *efi_systbl;
66 static struct efi_cfgtbl *efi_cfgtbl;
67 static struct efi_rt *efi_runtime;
68 
69 static int efi_status2err[25] = {
70 	0,		/* EFI_SUCCESS */
71 	ENOEXEC,	/* EFI_LOAD_ERROR */
72 	EINVAL,		/* EFI_INVALID_PARAMETER */
73 	ENOSYS,		/* EFI_UNSUPPORTED */
74 	EMSGSIZE, 	/* EFI_BAD_BUFFER_SIZE */
75 	EOVERFLOW,	/* EFI_BUFFER_TOO_SMALL */
76 	EBUSY,		/* EFI_NOT_READY */
77 	EIO,		/* EFI_DEVICE_ERROR */
78 	EROFS,		/* EFI_WRITE_PROTECTED */
79 	EAGAIN,		/* EFI_OUT_OF_RESOURCES */
80 	EIO,		/* EFI_VOLUME_CORRUPTED */
81 	ENOSPC,		/* EFI_VOLUME_FULL */
82 	ENXIO,		/* EFI_NO_MEDIA */
83 	ESTALE,		/* EFI_MEDIA_CHANGED */
84 	ENOENT,		/* EFI_NOT_FOUND */
85 	EACCES,		/* EFI_ACCESS_DENIED */
86 	ETIMEDOUT,	/* EFI_NO_RESPONSE */
87 	EADDRNOTAVAIL,	/* EFI_NO_MAPPING */
88 	ETIMEDOUT,	/* EFI_TIMEOUT */
89 	EDOOFUS,	/* EFI_NOT_STARTED */
90 	EALREADY,	/* EFI_ALREADY_STARTED */
91 	ECANCELED,	/* EFI_ABORTED */
92 	EPROTO,		/* EFI_ICMP_ERROR */
93 	EPROTO,		/* EFI_TFTP_ERROR */
94 	EPROTO		/* EFI_PROTOCOL_ERROR */
95 };
96 
97 MALLOC_DEFINE(M_EFI, "efi", "EFI BIOS");
98 
99 static int
100 efi_status_to_errno(efi_status status)
101 {
102 	u_long code;
103 
104 	code = status & 0x3ffffffffffffffful;
105 	return (code < nitems(efi_status2err) ? efi_status2err[code] : EDOOFUS);
106 }
107 
108 static struct lock efi_lock;
109 static struct lock resettodr_lock;
110 static mcontext_t efi_ctx;
111 static struct vmspace *efi_savevm;
112 static struct vmspace *efi_vmspace;
113 static vm_object_t efi_obj;
114 static struct efi_md *efi_map;
115 static int efi_ndesc;
116 static int efi_descsz;
117 
118 static void
119 efi_destroy_1t1_map(void)
120 {
121 	vm_object_t obj;
122 	vm_page_t m;
123 
124 	if ((obj = efi_obj) != NULL) {
125 		efi_obj = NULL;
126 		vm_object_hold(obj);
127 		vm_object_reference_locked(obj);	/* match deallocate */
128 	}
129 	if (efi_vmspace) {
130 		pmap_remove_pages(vmspace_pmap(efi_vmspace),
131 				  VM_MIN_USER_ADDRESS, VM_MAX_USER_ADDRESS);
132 		vm_map_remove(&efi_vmspace->vm_map,
133 			      VM_MIN_USER_ADDRESS,
134 			      VM_MAX_USER_ADDRESS);
135 		vmspace_rel(efi_vmspace);
136 		efi_vmspace = NULL;
137 	}
138 	if (obj) {
139 		while ((m = RB_ROOT(&obj->rb_memq)) != NULL) {
140 			vm_page_busy_wait(m, FALSE, "efipg");
141 			vm_page_unwire(m, 1);
142 			vm_page_flag_clear(m, PG_MAPPED | PG_WRITEABLE);
143 			cdev_pager_free_page(obj, m);
144 			kfree(m, M_EFI);
145 		}
146 		vm_object_drop(obj);
147 		vm_object_deallocate(obj);
148 	}
149 }
150 
151 static int
152 efi_pg_ctor(void *handle, vm_ooffset_t size, vm_prot_t prot,
153 	    vm_ooffset_t foff, struct ucred *cred, u_short *color)
154 {
155 	*color = 0;
156 	return 0;
157 }
158 
159 static void
160 efi_pg_dtor(void *handle)
161 {
162 }
163 
164 static int
165 efi_pg_fault(vm_object_t obj, vm_ooffset_t offset, int prot, vm_page_t *mres)
166 {
167 	vm_page_t m;
168 
169 	m = *mres;
170 	if ((m->flags & PG_FICTITIOUS) == 0) {
171 		*mres = NULL;
172 		vm_page_remove(m);
173 		vm_page_free(m);
174 		m = NULL;
175 	}
176 	if (m == NULL) {
177 		kprintf("efi_pg_fault: unmapped pg @%016jx\n", offset);
178 		return VM_PAGER_ERROR;
179 	}
180 
181 	/*
182 	 * Shouldn't get hit, we pre-loaded all the pages.
183 	 */
184 	kprintf("efi_pg_fault: ok %p/%p @%016jx m=%016jx,%016jx\n",
185 		obj, efi_obj, offset, m->pindex, m->phys_addr);
186 
187 	return VM_PAGER_OK;
188 }
189 
190 static struct cdev_pager_ops efi_pager_ops = {
191 	.cdev_pg_fault	= efi_pg_fault,
192 	.cdev_pg_ctor	= efi_pg_ctor,
193 	.cdev_pg_dtor	= efi_pg_dtor
194 };
195 
196 static bool
197 efi_create_1t1_map(struct efi_md *map, int ndesc, int descsz)
198 {
199 	vm_page_t m;
200 	struct efi_md *p;
201 	int i;
202 	int count;
203 	int result;
204 
205 	efi_map = map;
206 	efi_ndesc = ndesc;
207 	efi_descsz = descsz;
208 
209 	/*
210 	 * efi_obj is ref'd by cdev_pager_allocate
211 	 */
212 	efi_vmspace = vmspace_alloc(VM_MIN_USER_ADDRESS, VM_MAX_USER_ADDRESS);
213 	pmap_pinit2(vmspace_pmap(efi_vmspace));
214 	efi_obj = cdev_pager_allocate(NULL, OBJT_MGTDEVICE, &efi_pager_ops,
215 				  VM_MAX_USER_ADDRESS,
216 				  VM_PROT_READ | VM_PROT_WRITE,
217 				  0, proc0.p_ucred);
218 	vm_object_hold(efi_obj);
219 
220 	count = vm_map_entry_reserve(MAP_RESERVE_COUNT);
221 	vm_map_lock(&efi_vmspace->vm_map);
222 	result = vm_map_insert(&efi_vmspace->vm_map, &count, efi_obj, NULL,
223 			      0, NULL,
224 			      0, VM_MAX_USER_ADDRESS,
225 			      VM_MAPTYPE_NORMAL,
226 			      VM_SUBSYS_EFI,
227 			      VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE,
228 			      VM_PROT_READ | VM_PROT_WRITE | VM_PROT_EXECUTE,
229 			      0);
230 	vm_map_unlock(&efi_vmspace->vm_map);
231 	if (result != KERN_SUCCESS)
232 		goto fail;
233 
234 	for (i = 0, p = map;
235 	     i < ndesc; i++, p = efi_next_descriptor(p, descsz)) {
236 		vm_offset_t va;
237 		uint64_t idx;
238 		int mode;
239 
240 		if ((p->md_attr & EFI_MD_ATTR_RT) == 0)
241 			continue;
242 		if (p->md_virt != NULL) {
243 			if (bootverbose)
244 				kprintf("EFI Runtime entry %d is mapped\n", i);
245 			goto fail;
246 		}
247 		if ((p->md_phys & EFI_PAGE_MASK) != 0) {
248 			if (bootverbose)
249 				kprintf("EFI Runtime entry %d is not aligned\n",
250 				    i);
251 			goto fail;
252 		}
253 		if (p->md_phys + p->md_pages * EFI_PAGE_SIZE < p->md_phys ||
254 		    p->md_phys + p->md_pages * EFI_PAGE_SIZE >=
255 		    VM_MAX_USER_ADDRESS) {
256 			kprintf("EFI Runtime entry %d is not in mappable for RT:"
257 			    "base %#016jx %#jx pages\n",
258 			    i, (uintmax_t)p->md_phys,
259 			    (uintmax_t)p->md_pages);
260 			goto fail;
261 		}
262 
263 		if ((p->md_attr & EFI_MD_ATTR_WB) != 0)
264 			mode = VM_MEMATTR_WRITE_BACK;
265 		else if ((p->md_attr & EFI_MD_ATTR_WT) != 0)
266 			mode = VM_MEMATTR_WRITE_THROUGH;
267 		else if ((p->md_attr & EFI_MD_ATTR_WC) != 0)
268 			mode = VM_MEMATTR_WRITE_COMBINING;
269 		else if ((p->md_attr & EFI_MD_ATTR_WP) != 0)
270 			mode = VM_MEMATTR_WRITE_PROTECTED;
271 		else if ((p->md_attr & EFI_MD_ATTR_UC) != 0)
272 			mode = VM_MEMATTR_UNCACHEABLE;
273 		else {
274 			if (bootverbose)
275 				kprintf("EFI Runtime entry %d mapping "
276 				    "attributes unsupported\n", i);
277 			mode = VM_MEMATTR_UNCACHEABLE;
278 		}
279 
280 		if (bootverbose) {
281 			kprintf("efirt: map %016jx-%016jx\n",
282 				p->md_phys,
283 				p->md_phys + IDX_TO_OFF(p->md_pages));
284 		}
285 
286 		for (va = p->md_phys, idx = 0; idx < p->md_pages; idx++,
287 		    va += PAGE_SIZE) {
288 			m = kmalloc(sizeof(*m), M_EFI, M_WAITOK | M_ZERO);
289 			/*m->flags |= PG_WRITEABLE;*/
290 			vm_page_initfake(m, va, mode);	/* va is phys addr */
291 			m->valid = VM_PAGE_BITS_ALL;
292 			m->dirty = m->valid;
293 			vm_page_insert(m, efi_obj, OFF_TO_IDX(va));
294 			vm_page_wakeup(m);
295 		}
296 	}
297 	vm_object_drop(efi_obj);
298 	vm_map_entry_release(count);
299 
300 	return true;
301 
302 fail:
303 	vm_object_drop(efi_obj);
304 	vm_map_entry_release(count);
305 	efi_destroy_1t1_map();
306 
307 	return false;
308 }
309 
310 /*
311  * Create an environment for the EFI runtime code call.  The most
312  * important part is creating the required 1:1 physical->virtual
313  * mappings for the runtime segments.  To do that, we manually create
314  * page table which unmap userspace but gives correct kernel mapping.
315  * The 1:1 mappings for runtime segments usually occupy low 4G of the
316  * physical address map.
317  *
318  * The 1:1 mappings were chosen over the SetVirtualAddressMap() EFI RT
319  * service, because there are some BIOSes which fail to correctly
320  * relocate itself on the call, requiring both 1:1 and virtual
321  * mapping.  As result, we must provide 1:1 mapping anyway, so no
322  * reason to bother with the virtual map, and no need to add a
323  * complexity into loader.
324  *
325  * The fpu_kern_enter() call allows firmware to use FPU, as mandated
326  * by the specification.  In particular, CR0.TS bit is cleared.  Also
327  * it enters critical section, giving us neccessary protection against
328  * context switch.
329  *
330  * There is no need to disable interrupts around the change of %cr3,
331  * the kernel mappings are correct, while we only grabbed the
332  * userspace portion of VA.  Interrupts handlers must not access
333  * userspace.  Having interrupts enabled fixes the issue with
334  * firmware/SMM long operation, which would negatively affect IPIs,
335  * esp. TLB shootdown requests.
336  */
337 static int
338 efi_enter(void)
339 {
340 	thread_t td = curthread;
341 
342 	if (efi_runtime == NULL)
343 		return (ENXIO);
344 	lockmgr(&efi_lock, LK_EXCLUSIVE);
345 	efi_savevm = td->td_lwp->lwp_vmspace;
346 	pmap_setlwpvm(td->td_lwp, efi_vmspace);
347 	npxpush(&efi_ctx);
348 	cpu_invltlb();
349 
350 	return (0);
351 }
352 
353 static void
354 efi_leave(void)
355 {
356 	thread_t td = curthread;
357 
358 	pmap_setlwpvm(td->td_lwp, efi_savevm);
359 	npxpop(&efi_ctx);
360 	cpu_invltlb();
361 	efi_savevm = NULL;
362 	lockmgr(&efi_lock, LK_RELEASE);
363 }
364 
365 static int
366 efi_init(void)
367 {
368 	struct efi_map_header *efihdr;
369 	struct efi_md *map;
370 	caddr_t kmdp;
371 	size_t efisz;
372 
373 	lockinit(&efi_lock, "efi", 0, LK_CANRECURSE);
374 	lockinit(&resettodr_lock, "efitodr", 0, LK_CANRECURSE);
375 
376 	if (efi_systbl_phys == 0) {
377 		if (bootverbose)
378 			kprintf("EFI systbl not available\n");
379 		return (ENXIO);
380 	}
381 	efi_systbl = (struct efi_systbl *)PHYS_TO_DMAP(efi_systbl_phys);
382 	if (efi_systbl->st_hdr.th_sig != EFI_SYSTBL_SIG) {
383 		efi_systbl = NULL;
384 		if (bootverbose)
385 			kprintf("EFI systbl signature invalid\n");
386 		return (ENXIO);
387 	}
388 	efi_cfgtbl = (efi_systbl->st_cfgtbl == 0) ? NULL :
389 	    (struct efi_cfgtbl *)efi_systbl->st_cfgtbl;
390 	if (efi_cfgtbl == NULL) {
391 		if (bootverbose)
392 			kprintf("EFI config table is not present\n");
393 	}
394 
395 	kmdp = preload_search_by_type("elf kernel");
396 	if (kmdp == NULL)
397 		kmdp = preload_search_by_type("elf64 kernel");
398 	efihdr = (struct efi_map_header *)preload_search_info(kmdp,
399 	    MODINFO_METADATA | MODINFOMD_EFI_MAP);
400 	if (efihdr == NULL) {
401 		if (bootverbose)
402 			kprintf("EFI map is not present\n");
403 		return (ENXIO);
404 	}
405 	efisz = (sizeof(struct efi_map_header) + 0xf) & ~0xf;
406 	map = (struct efi_md *)((uint8_t *)efihdr + efisz);
407 	if (efihdr->descriptor_size == 0)
408 		return (ENOMEM);
409 
410 	if (!efi_create_1t1_map(map, efihdr->memory_size /
411 	    efihdr->descriptor_size, efihdr->descriptor_size)) {
412 		if (bootverbose)
413 			kprintf("EFI cannot create runtime map\n");
414 		return (ENOMEM);
415 	}
416 
417 	efi_runtime = (efi_systbl->st_rt == 0) ? NULL :
418 			(struct efi_rt *)efi_systbl->st_rt;
419 	if (efi_runtime == NULL) {
420 		if (bootverbose)
421 			kprintf("EFI runtime services table is not present\n");
422 		efi_destroy_1t1_map();
423 		return (ENXIO);
424 	}
425 
426 	return (0);
427 }
428 
429 static void
430 efi_uninit(void)
431 {
432 	efi_destroy_1t1_map();
433 
434 	efi_systbl = NULL;
435 	efi_cfgtbl = NULL;
436 	efi_runtime = NULL;
437 
438 	lockuninit(&efi_lock);
439 	lockuninit(&resettodr_lock);
440 }
441 
442 int
443 efi_get_table(struct uuid *uuid, void **ptr)
444 {
445 	struct efi_cfgtbl *ct;
446 	u_long count;
447 
448 	if (efi_cfgtbl == NULL)
449 		return (ENXIO);
450 	count = efi_systbl->st_entries;
451 	ct = efi_cfgtbl;
452 	while (count--) {
453 		if (!bcmp(&ct->ct_uuid, uuid, sizeof(*uuid))) {
454 			*ptr = (void *)PHYS_TO_DMAP(ct->ct_data);
455 			return (0);
456 		}
457 		ct++;
458 	}
459 	return (ENOENT);
460 }
461 
462 char SaveCode[1024];
463 
464 int
465 efi_get_time_locked(struct efi_tm *tm)
466 {
467 	efi_status status;
468 	int error;
469 
470 	KKASSERT(lockowned(&resettodr_lock) != 0);
471 	error = efi_enter();
472 	if (error != 0)
473 		return (error);
474 	status = efi_runtime->rt_gettime(tm, NULL);
475 	efi_leave();
476 	error = efi_status_to_errno(status);
477 
478 	return (error);
479 }
480 
481 int
482 efi_get_time(struct efi_tm *tm)
483 {
484 	int error;
485 
486 	if (efi_runtime == NULL)
487 		return (ENXIO);
488 	lockmgr(&resettodr_lock, LK_EXCLUSIVE);
489 	error = efi_get_time_locked(tm);
490 	lockmgr(&resettodr_lock, LK_RELEASE);
491 
492 	return (error);
493 }
494 
495 int
496 efi_reset_system(void)
497 {
498 	int error;
499 
500 	error = efi_enter();
501 	if (error != 0)
502 		return (error);
503 	efi_runtime->rt_reset(EFI_RESET_WARM, 0, 0, NULL);
504 	efi_leave();
505 	return (EIO);
506 }
507 
508 int
509 efi_set_time_locked(struct efi_tm *tm)
510 {
511 	efi_status status;
512 	int error;
513 
514 	KKASSERT(lockowned(&resettodr_lock) != 0);
515 	error = efi_enter();
516 	if (error != 0)
517 		return (error);
518 	status = efi_runtime->rt_settime(tm);
519 	efi_leave();
520 	error = efi_status_to_errno(status);
521 	return (error);
522 }
523 
524 int
525 efi_set_time(struct efi_tm *tm)
526 {
527 	int error;
528 
529 	if (efi_runtime == NULL)
530 		return (ENXIO);
531 	lockmgr(&resettodr_lock, LK_EXCLUSIVE);
532 	error = efi_set_time_locked(tm);
533 	lockmgr(&resettodr_lock, LK_RELEASE);
534 	return (error);
535 }
536 
537 int
538 efi_var_get(efi_char *name, struct uuid *vendor, uint32_t *attrib,
539     size_t *datasize, void *data)
540 {
541 	efi_status status;
542 	int error;
543 
544 	error = efi_enter();
545 	if (error != 0)
546 		return (error);
547 	status = efi_runtime->rt_getvar(name, vendor, attrib, datasize, data);
548 	efi_leave();
549 	error = efi_status_to_errno(status);
550 	return (error);
551 }
552 
553 int
554 efi_var_nextname(size_t *namesize, efi_char *name, struct uuid *vendor)
555 {
556 	efi_status status;
557 	int error;
558 
559 	error = efi_enter();
560 	if (error != 0)
561 		return (error);
562 	status = efi_runtime->rt_scanvar(namesize, name, vendor);
563 	efi_leave();
564 	error = efi_status_to_errno(status);
565 	return (error);
566 }
567 
568 int
569 efi_var_set(efi_char *name, struct uuid *vendor, uint32_t attrib,
570     size_t datasize, void *data)
571 {
572 	efi_status status;
573 	int error;
574 
575 	error = efi_enter();
576 	if (error != 0)
577 		return (error);
578 	status = efi_runtime->rt_setvar(name, vendor, attrib, datasize, data);
579 	efi_leave();
580 	error = efi_status_to_errno(status);
581 	return (error);
582 }
583 
584 static int
585 efirt_modevents(module_t m, int event, void *arg __unused)
586 {
587 
588 	switch (event) {
589 	case MOD_LOAD:
590 		return (efi_init());
591 
592 	case MOD_UNLOAD:
593 		efi_uninit();
594 		return (0);
595 
596 	case MOD_SHUTDOWN:
597 		return (0);
598 
599 	default:
600 		return (EOPNOTSUPP);
601 	}
602 }
603 
604 static moduledata_t efirt_moddata = {
605 	.name = "efirt",
606 	.evhand = efirt_modevents,
607 	.priv = NULL,
608 };
609 
610 DECLARE_MODULE(efirt, efirt_moddata, SI_SUB_DRIVERS, SI_ORDER_ANY);
611 MODULE_VERSION(efirt, 1);
612 
613 
614 /* XXX debug stuff */
615 static int
616 efi_time_sysctl_handler(SYSCTL_HANDLER_ARGS)
617 {
618 	struct efi_tm tm;
619 	int error, val;
620 
621 	val = 0;
622 	error = sysctl_handle_int(oidp, &val, 0, req);
623 	if (error != 0 || req->newptr == NULL)
624 		return (error);
625 	error = efi_get_time(&tm);
626 	if (error == 0) {
627 		uprintf("EFI reports: Year %d Month %d Day %d Hour %d Min %d "
628 		    "Sec %d\n", tm.tm_year, tm.tm_mon, tm.tm_mday, tm.tm_hour,
629 		    tm.tm_min, tm.tm_sec);
630 	}
631 	return (error);
632 }
633 
634 SYSCTL_PROC(_debug, OID_AUTO, efi_time, CTLTYPE_INT | CTLFLAG_RW, NULL, 0,
635 	    efi_time_sysctl_handler, "I", "");
636