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
32 #include <sys/param.h>
33 #include <sys/efi.h>
34 #include <sys/kernel.h>
35 #include <sys/linker.h>
36 #include <sys/lock.h>
37 #include <sys/module.h>
38 #include <sys/mutex.h>
39 #include <sys/clock.h>
40 #include <sys/proc.h>
41 #include <sys/rwlock.h>
42 #include <sys/sched.h>
43 #include <sys/sysctl.h>
44 #include <sys/systm.h>
45 #include <sys/vmmeter.h>
46 #include <isa/rtc.h>
47 #include <machine/efi.h>
48 #include <machine/md_var.h>
49 #include <machine/vmparam.h>
50 #include <vm/vm.h>
51 #include <vm/pmap.h>
52 #include <vm/vm_extern.h>
53 #include <vm/vm_map.h>
54 #include <vm/vm_object.h>
55 #include <vm/vm_page.h>
56 #include <vm/vm_pager.h>
57
58 static pml5_entry_t *efi_pml5;
59 static pml4_entry_t *efi_pml4;
60 static vm_object_t obj_1t1_pt;
61 static vm_page_t efi_pmltop_page;
62 static vm_pindex_t efi_1t1_idx;
63
64 void
efi_destroy_1t1_map(void)65 efi_destroy_1t1_map(void)
66 {
67 vm_page_t m;
68
69 if (obj_1t1_pt != NULL) {
70 VM_OBJECT_RLOCK(obj_1t1_pt);
71 TAILQ_FOREACH(m, &obj_1t1_pt->memq, listq)
72 m->ref_count = VPRC_OBJREF;
73 vm_wire_sub(obj_1t1_pt->resident_page_count);
74 VM_OBJECT_RUNLOCK(obj_1t1_pt);
75 vm_object_deallocate(obj_1t1_pt);
76 }
77
78 obj_1t1_pt = NULL;
79 efi_pml4 = NULL;
80 efi_pml5 = NULL;
81 efi_pmltop_page = NULL;
82 }
83
84 /*
85 * Map a physical address from EFI runtime space into KVA space. Returns 0 to
86 * indicate a failed mapping so that the caller may handle error.
87 */
88 vm_offset_t
efi_phys_to_kva(vm_paddr_t paddr)89 efi_phys_to_kva(vm_paddr_t paddr)
90 {
91
92 if (paddr >= dmaplimit)
93 return (0);
94 return (PHYS_TO_DMAP(paddr));
95 }
96
97 static vm_page_t
efi_1t1_page(void)98 efi_1t1_page(void)
99 {
100
101 return (vm_page_grab(obj_1t1_pt, efi_1t1_idx++, VM_ALLOC_NOBUSY |
102 VM_ALLOC_WIRED | VM_ALLOC_ZERO));
103 }
104
105 static pt_entry_t *
efi_1t1_pte(vm_offset_t va)106 efi_1t1_pte(vm_offset_t va)
107 {
108 pml5_entry_t *pml5e;
109 pml4_entry_t *pml4e;
110 pdp_entry_t *pdpe;
111 pd_entry_t *pde;
112 pt_entry_t *pte;
113 vm_page_t m;
114 vm_pindex_t pml5_idx, pml4_idx, pdp_idx, pd_idx;
115 vm_paddr_t mphys;
116
117 pml4_idx = pmap_pml4e_index(va);
118 if (la57) {
119 pml5_idx = pmap_pml5e_index(va);
120 pml5e = &efi_pml5[pml5_idx];
121 if (*pml5e == 0) {
122 m = efi_1t1_page();
123 mphys = VM_PAGE_TO_PHYS(m);
124 *pml5e = mphys | X86_PG_RW | X86_PG_V;
125 } else {
126 mphys = *pml5e & PG_FRAME;
127 }
128 pml4e = (pml4_entry_t *)PHYS_TO_DMAP(mphys);
129 pml4e = &pml4e[pml4_idx];
130 } else {
131 pml4e = &efi_pml4[pml4_idx];
132 }
133
134 if (*pml4e == 0) {
135 m = efi_1t1_page();
136 mphys = VM_PAGE_TO_PHYS(m);
137 *pml4e = mphys | X86_PG_RW | X86_PG_V;
138 } else {
139 mphys = *pml4e & PG_FRAME;
140 }
141
142 pdpe = (pdp_entry_t *)PHYS_TO_DMAP(mphys);
143 pdp_idx = pmap_pdpe_index(va);
144 pdpe += pdp_idx;
145 if (*pdpe == 0) {
146 m = efi_1t1_page();
147 mphys = VM_PAGE_TO_PHYS(m);
148 *pdpe = mphys | X86_PG_RW | X86_PG_V;
149 } else {
150 mphys = *pdpe & PG_FRAME;
151 }
152
153 pde = (pd_entry_t *)PHYS_TO_DMAP(mphys);
154 pd_idx = pmap_pde_index(va);
155 pde += pd_idx;
156 if (*pde == 0) {
157 m = efi_1t1_page();
158 mphys = VM_PAGE_TO_PHYS(m);
159 *pde = mphys | X86_PG_RW | X86_PG_V;
160 } else {
161 mphys = *pde & PG_FRAME;
162 }
163
164 pte = (pt_entry_t *)PHYS_TO_DMAP(mphys);
165 pte += pmap_pte_index(va);
166 KASSERT(*pte == 0, ("va %#jx *pt %#jx", va, *pte));
167
168 return (pte);
169 }
170
171 bool
efi_create_1t1_map(struct efi_md * map,int ndesc,int descsz)172 efi_create_1t1_map(struct efi_md *map, int ndesc, int descsz)
173 {
174 struct efi_md *p;
175 pt_entry_t *pte;
176 void *pml;
177 vm_page_t m;
178 vm_offset_t va;
179 uint64_t idx;
180 int bits, i, mode;
181
182 obj_1t1_pt = vm_pager_allocate(OBJT_PHYS, NULL, ptoa(1 +
183 NPML4EPG + NPML4EPG * NPDPEPG + NPML4EPG * NPDPEPG * NPDEPG),
184 VM_PROT_ALL, 0, NULL);
185 efi_1t1_idx = 0;
186 VM_OBJECT_WLOCK(obj_1t1_pt);
187 efi_pmltop_page = efi_1t1_page();
188 VM_OBJECT_WUNLOCK(obj_1t1_pt);
189 pml = (void *)PHYS_TO_DMAP(VM_PAGE_TO_PHYS(efi_pmltop_page));
190 if (la57) {
191 efi_pml5 = pml;
192 pmap_pinit_pml5(efi_pmltop_page);
193 } else {
194 efi_pml4 = pml;
195 pmap_pinit_pml4(efi_pmltop_page);
196 }
197
198 for (i = 0, p = map; i < ndesc; i++, p = efi_next_descriptor(p,
199 descsz)) {
200 if ((p->md_attr & EFI_MD_ATTR_RT) == 0)
201 continue;
202 if (p->md_virt != 0 && p->md_virt != p->md_phys) {
203 if (bootverbose)
204 printf("EFI Runtime entry %d is mapped\n", i);
205 goto fail;
206 }
207 if ((p->md_phys & EFI_PAGE_MASK) != 0) {
208 if (bootverbose)
209 printf("EFI Runtime entry %d is not aligned\n",
210 i);
211 goto fail;
212 }
213 if (p->md_phys + p->md_pages * EFI_PAGE_SIZE < p->md_phys ||
214 p->md_phys + p->md_pages * EFI_PAGE_SIZE >=
215 VM_MAXUSER_ADDRESS) {
216 printf("EFI Runtime entry %d is not in mappable for RT:"
217 "base %#016jx %#jx pages\n",
218 i, (uintmax_t)p->md_phys,
219 (uintmax_t)p->md_pages);
220 goto fail;
221 }
222 if ((p->md_attr & EFI_MD_ATTR_WB) != 0)
223 mode = VM_MEMATTR_WRITE_BACK;
224 else if ((p->md_attr & EFI_MD_ATTR_WT) != 0)
225 mode = VM_MEMATTR_WRITE_THROUGH;
226 else if ((p->md_attr & EFI_MD_ATTR_WC) != 0)
227 mode = VM_MEMATTR_WRITE_COMBINING;
228 else if ((p->md_attr & EFI_MD_ATTR_WP) != 0)
229 mode = VM_MEMATTR_WRITE_PROTECTED;
230 else if ((p->md_attr & EFI_MD_ATTR_UC) != 0)
231 mode = VM_MEMATTR_UNCACHEABLE;
232 else {
233 if (bootverbose)
234 printf("EFI Runtime entry %d mapping "
235 "attributes unsupported\n", i);
236 mode = VM_MEMATTR_UNCACHEABLE;
237 }
238 bits = pmap_cache_bits(kernel_pmap, mode, false) | X86_PG_RW |
239 X86_PG_V;
240 VM_OBJECT_WLOCK(obj_1t1_pt);
241 for (va = p->md_phys, idx = 0; idx < p->md_pages; idx++,
242 va += PAGE_SIZE) {
243 pte = efi_1t1_pte(va);
244 pte_store(pte, va | bits);
245
246 m = PHYS_TO_VM_PAGE(va);
247 if (m != NULL && VM_PAGE_TO_PHYS(m) == 0) {
248 vm_page_init_page(m, va, -1,
249 VM_FREEPOOL_DEFAULT);
250 m->order = VM_NFREEORDER + 1; /* invalid */
251 m->pool = VM_NFREEPOOL + 1; /* invalid */
252 pmap_page_set_memattr_noflush(m, mode);
253 }
254 }
255 VM_OBJECT_WUNLOCK(obj_1t1_pt);
256 }
257
258 return (true);
259
260 fail:
261 efi_destroy_1t1_map();
262 return (false);
263 }
264
265 /*
266 * Create an environment for the EFI runtime code call. The most
267 * important part is creating the required 1:1 physical->virtual
268 * mappings for the runtime segments. To do that, we manually create
269 * page table which unmap userspace but gives correct kernel mapping.
270 * The 1:1 mappings for runtime segments usually occupy low 4G of the
271 * physical address map.
272 *
273 * The 1:1 mappings were chosen over the SetVirtualAddressMap() EFI RT
274 * service, because there are some BIOSes which fail to correctly
275 * relocate itself on the call, requiring both 1:1 and virtual
276 * mapping. As result, we must provide 1:1 mapping anyway, so no
277 * reason to bother with the virtual map, and no need to add a
278 * complexity into loader.
279 *
280 * There is no need to disable interrupts around the change of %cr3,
281 * the kernel mappings are correct, while we only grabbed the
282 * userspace portion of VA. Interrupts handlers must not access
283 * userspace. Having interrupts enabled fixes the issue with
284 * firmware/SMM long operation, which would negatively affect IPIs,
285 * esp. TLB shootdown requests.
286 */
287 int
efi_arch_enter(void)288 efi_arch_enter(void)
289 {
290 pmap_t curpmap;
291 uint64_t cr3;
292
293 curpmap = PCPU_GET(curpmap);
294 PMAP_LOCK_ASSERT(curpmap, MA_OWNED);
295 curthread->td_md.md_efirt_dis_pf = vm_fault_disable_pagefaults();
296
297 /*
298 * IPI TLB shootdown handler invltlb_pcid_handler() reloads
299 * %cr3 from the curpmap->pm_cr3, which would disable runtime
300 * segments mappings. Block the handler's action by setting
301 * curpmap to impossible value. See also comment in
302 * pmap.c:pmap_activate_sw().
303 */
304 if (pmap_pcid_enabled && !invpcid_works)
305 PCPU_SET(curpmap, NULL);
306
307 cr3 = VM_PAGE_TO_PHYS(efi_pmltop_page);
308 if (pmap_pcid_enabled)
309 cr3 |= pmap_get_pcid(curpmap);
310 load_cr3(cr3);
311 /*
312 * If PCID is enabled, the clear CR3_PCID_SAVE bit in the loaded %cr3
313 * causes TLB invalidation.
314 */
315 if (!pmap_pcid_enabled)
316 invltlb();
317 return (0);
318 }
319
320 void
efi_arch_leave(void)321 efi_arch_leave(void)
322 {
323 pmap_t curpmap;
324 uint64_t cr3;
325
326 curpmap = &curproc->p_vmspace->vm_pmap;
327 cr3 = curpmap->pm_cr3;
328 if (pmap_pcid_enabled) {
329 cr3 |= pmap_get_pcid(curpmap);
330 if (!invpcid_works)
331 PCPU_SET(curpmap, curpmap);
332 }
333 load_cr3(cr3);
334 if (!pmap_pcid_enabled)
335 invltlb();
336 vm_fault_enable_pagefaults(curthread->td_md.md_efirt_dis_pf);
337 }
338
339 /* XXX debug stuff */
340 static int
efi_time_sysctl_handler(SYSCTL_HANDLER_ARGS)341 efi_time_sysctl_handler(SYSCTL_HANDLER_ARGS)
342 {
343 struct efi_tm tm;
344 int error, val;
345
346 val = 0;
347 error = sysctl_handle_int(oidp, &val, 0, req);
348 if (error != 0 || req->newptr == NULL)
349 return (error);
350 error = efi_get_time(&tm);
351 if (error == 0) {
352 uprintf("EFI reports: Year %d Month %d Day %d Hour %d Min %d "
353 "Sec %d\n", tm.tm_year, tm.tm_mon, tm.tm_mday, tm.tm_hour,
354 tm.tm_min, tm.tm_sec);
355 }
356 return (error);
357 }
358
359 SYSCTL_PROC(_debug, OID_AUTO, efi_time,
360 CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE, NULL, 0,
361 efi_time_sysctl_handler, "I",
362 "");
363