Commit | Line | Data |
---|---|---|
31625340 JC |
1 | /* |
2 | * tboot.c: main implementation of helper functions used by kernel for | |
3 | * runtime support of Intel(R) Trusted Execution Technology | |
4 | * | |
5 | * Copyright (c) 2006-2009, Intel Corporation | |
6 | * | |
7 | * This program is free software; you can redistribute it and/or modify it | |
8 | * under the terms and conditions of the GNU General Public License, | |
9 | * version 2, as published by the Free Software Foundation. | |
10 | * | |
11 | * This program is distributed in the hope it will be useful, but WITHOUT | |
12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
14 | * more details. | |
15 | * | |
16 | * You should have received a copy of the GNU General Public License along with | |
17 | * this program; if not, write to the Free Software Foundation, Inc., | |
18 | * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA. | |
19 | * | |
20 | */ | |
21 | ||
22 | #include <linux/dma_remapping.h> | |
23 | #include <linux/init_task.h> | |
24 | #include <linux/spinlock.h> | |
69c60c88 | 25 | #include <linux/export.h> |
69575d38 | 26 | #include <linux/delay.h> |
31625340 JC |
27 | #include <linux/sched.h> |
28 | #include <linux/init.h> | |
29 | #include <linux/dmar.h> | |
69575d38 | 30 | #include <linux/cpu.h> |
31625340 JC |
31 | #include <linux/pfn.h> |
32 | #include <linux/mm.h> | |
69575d38 | 33 | #include <linux/tboot.h> |
13bfd47a | 34 | #include <linux/debugfs.h> |
31625340 | 35 | |
c9b77ccb | 36 | #include <asm/realmode.h> |
31625340 JC |
37 | #include <asm/processor.h> |
38 | #include <asm/bootparam.h> | |
39 | #include <asm/pgtable.h> | |
40 | #include <asm/pgalloc.h> | |
b7f080cf | 41 | #include <asm/swiotlb.h> |
81e2d7b3 | 42 | #include <asm/fixmap.h> |
58c41d28 | 43 | #include <asm/proto.h> |
31625340 | 44 | #include <asm/setup.h> |
31625340 JC |
45 | #include <asm/e820.h> |
46 | #include <asm/io.h> | |
47 | ||
bf8b88e9 | 48 | #include "../realmode/rm/wakeup.h" |
31625340 JC |
49 | |
50 | /* Global pointer to shared data; NULL means no measured launch. */ | |
51 | struct tboot *tboot __read_mostly; | |
cafd6659 | 52 | EXPORT_SYMBOL(tboot); |
31625340 JC |
53 | |
54 | /* timeout for APs (in secs) to enter wait-for-SIPI state during shutdown */ | |
55 | #define AP_WAIT_TIMEOUT 1 | |
56 | ||
57 | #undef pr_fmt | |
58 | #define pr_fmt(fmt) "tboot: " fmt | |
59 | ||
60 | static u8 tboot_uuid[16] __initdata = TBOOT_UUID; | |
61 | ||
62 | void __init tboot_probe(void) | |
63 | { | |
64 | /* Look for valid page-aligned address for shared page. */ | |
65 | if (!boot_params.tboot_addr) | |
66 | return; | |
67 | /* | |
68 | * also verify that it is mapped as we expect it before calling | |
69 | * set_fixmap(), to reduce chance of garbage value causing crash | |
70 | */ | |
71 | if (!e820_any_mapped(boot_params.tboot_addr, | |
72 | boot_params.tboot_addr, E820_RESERVED)) { | |
73 | pr_warning("non-0 tboot_addr but it is not of type E820_RESERVED\n"); | |
74 | return; | |
75 | } | |
76 | ||
77 | /* only a natively booted kernel should be using TXT */ | |
78 | if (paravirt_enabled()) { | |
79 | pr_warning("non-0 tboot_addr but pv_ops is enabled\n"); | |
80 | return; | |
81 | } | |
82 | ||
83 | /* Map and check for tboot UUID. */ | |
84 | set_fixmap(FIX_TBOOT_BASE, boot_params.tboot_addr); | |
85 | tboot = (struct tboot *)fix_to_virt(FIX_TBOOT_BASE); | |
86 | if (memcmp(&tboot_uuid, &tboot->uuid, sizeof(tboot->uuid))) { | |
87 | pr_warning("tboot at 0x%llx is invalid\n", | |
88 | boot_params.tboot_addr); | |
89 | tboot = NULL; | |
90 | return; | |
91 | } | |
92 | if (tboot->version < 5) { | |
93 | pr_warning("tboot version is invalid: %u\n", tboot->version); | |
94 | tboot = NULL; | |
95 | return; | |
96 | } | |
97 | ||
98 | pr_info("found shared page at phys addr 0x%llx:\n", | |
99 | boot_params.tboot_addr); | |
100 | pr_debug("version: %d\n", tboot->version); | |
101 | pr_debug("log_addr: 0x%08x\n", tboot->log_addr); | |
102 | pr_debug("shutdown_entry: 0x%x\n", tboot->shutdown_entry); | |
103 | pr_debug("tboot_base: 0x%08x\n", tboot->tboot_base); | |
104 | pr_debug("tboot_size: 0x%x\n", tboot->tboot_size); | |
105 | } | |
106 | ||
11520e5e LT |
107 | static pgd_t *tboot_pg_dir; |
108 | static struct mm_struct tboot_mm = { | |
109 | .mm_rb = RB_ROOT, | |
110 | .pgd = swapper_pg_dir, | |
111 | .mm_users = ATOMIC_INIT(2), | |
112 | .mm_count = ATOMIC_INIT(1), | |
113 | .mmap_sem = __RWSEM_INITIALIZER(init_mm.mmap_sem), | |
114 | .page_table_lock = __SPIN_LOCK_UNLOCKED(init_mm.page_table_lock), | |
115 | .mmlist = LIST_HEAD_INIT(init_mm.mmlist), | |
116 | }; | |
117 | ||
31625340 JC |
118 | static inline void switch_to_tboot_pt(void) |
119 | { | |
11520e5e LT |
120 | write_cr3(virt_to_phys(tboot_pg_dir)); |
121 | } | |
122 | ||
123 | static int map_tboot_page(unsigned long vaddr, unsigned long pfn, | |
124 | pgprot_t prot) | |
125 | { | |
126 | pgd_t *pgd; | |
127 | pud_t *pud; | |
128 | pmd_t *pmd; | |
129 | pte_t *pte; | |
130 | ||
131 | pgd = pgd_offset(&tboot_mm, vaddr); | |
132 | pud = pud_alloc(&tboot_mm, pgd, vaddr); | |
133 | if (!pud) | |
134 | return -1; | |
135 | pmd = pmd_alloc(&tboot_mm, pud, vaddr); | |
136 | if (!pmd) | |
137 | return -1; | |
3ed3a4f0 | 138 | pte = pte_alloc_map(&tboot_mm, pmd, vaddr); |
11520e5e LT |
139 | if (!pte) |
140 | return -1; | |
141 | set_pte_at(&tboot_mm, vaddr, pte, pfn_pte(pfn, prot)); | |
142 | pte_unmap(pte); | |
143 | return 0; | |
144 | } | |
145 | ||
146 | static int map_tboot_pages(unsigned long vaddr, unsigned long start_pfn, | |
147 | unsigned long nr) | |
148 | { | |
149 | /* Reuse the original kernel mapping */ | |
150 | tboot_pg_dir = pgd_alloc(&tboot_mm); | |
151 | if (!tboot_pg_dir) | |
152 | return -1; | |
153 | ||
154 | for (; nr > 0; nr--, vaddr += PAGE_SIZE, start_pfn++) { | |
155 | if (map_tboot_page(vaddr, start_pfn, PAGE_KERNEL_EXEC)) | |
156 | return -1; | |
157 | } | |
158 | ||
159 | return 0; | |
160 | } | |
161 | ||
162 | static void tboot_create_trampoline(void) | |
163 | { | |
164 | u32 map_base, map_size; | |
165 | ||
166 | /* Create identity map for tboot shutdown code. */ | |
167 | map_base = PFN_DOWN(tboot->tboot_base); | |
168 | map_size = PFN_UP(tboot->tboot_size); | |
169 | if (map_tboot_pages(map_base << PAGE_SHIFT, map_base, map_size)) | |
170 | panic("tboot: Error mapping tboot pages (mfns) @ 0x%x, 0x%x\n", | |
171 | map_base, map_size); | |
31625340 JC |
172 | } |
173 | ||
58c41d28 PA |
174 | #ifdef CONFIG_ACPI_SLEEP |
175 | ||
176 | static void add_mac_region(phys_addr_t start, unsigned long size) | |
31625340 | 177 | { |
58c41d28 PA |
178 | struct tboot_mac_region *mr; |
179 | phys_addr_t end = start + size; | |
180 | ||
4bd96a7a SW |
181 | if (tboot->num_mac_regions >= MAX_TB_MAC_REGIONS) |
182 | panic("tboot: Too many MAC regions\n"); | |
183 | ||
58c41d28 PA |
184 | if (start && size) { |
185 | mr = &tboot->mac_regions[tboot->num_mac_regions++]; | |
186 | mr->start = round_down(start, PAGE_SIZE); | |
187 | mr->size = round_up(end, PAGE_SIZE) - mr->start; | |
188 | } | |
189 | } | |
190 | ||
191 | static int tboot_setup_sleep(void) | |
192 | { | |
4bd96a7a SW |
193 | int i; |
194 | ||
58c41d28 PA |
195 | tboot->num_mac_regions = 0; |
196 | ||
4bd96a7a SW |
197 | for (i = 0; i < e820.nr_map; i++) { |
198 | if ((e820.map[i].type != E820_RAM) | |
199 | && (e820.map[i].type != E820_RESERVED_KERN)) | |
200 | continue; | |
62a3207b | 201 | |
4bd96a7a SW |
202 | add_mac_region(e820.map[i].addr, e820.map[i].size); |
203 | } | |
58c41d28 | 204 | |
c9b77ccb | 205 | tboot->acpi_sinfo.kernel_s3_resume_vector = |
b429dbf6 | 206 | real_mode_header->wakeup_start; |
58c41d28 PA |
207 | |
208 | return 0; | |
209 | } | |
210 | ||
211 | #else /* no CONFIG_ACPI_SLEEP */ | |
212 | ||
213 | static int tboot_setup_sleep(void) | |
214 | { | |
215 | /* S3 shutdown requested, but S3 not supported by the kernel... */ | |
216 | BUG(); | |
217 | return -1; | |
31625340 JC |
218 | } |
219 | ||
58c41d28 PA |
220 | #endif |
221 | ||
31625340 JC |
222 | void tboot_shutdown(u32 shutdown_type) |
223 | { | |
224 | void (*shutdown)(void); | |
225 | ||
226 | if (!tboot_enabled()) | |
227 | return; | |
228 | ||
11520e5e LT |
229 | /* |
230 | * if we're being called before the 1:1 mapping is set up then just | |
231 | * return and let the normal shutdown happen; this should only be | |
232 | * due to very early panic() | |
233 | */ | |
234 | if (!tboot_pg_dir) | |
235 | return; | |
236 | ||
31625340 JC |
237 | /* if this is S3 then set regions to MAC */ |
238 | if (shutdown_type == TB_SHUTDOWN_S3) | |
58c41d28 PA |
239 | if (tboot_setup_sleep()) |
240 | return; | |
31625340 JC |
241 | |
242 | tboot->shutdown_type = shutdown_type; | |
243 | ||
244 | switch_to_tboot_pt(); | |
245 | ||
246 | shutdown = (void(*)(void))(unsigned long)tboot->shutdown_entry; | |
247 | shutdown(); | |
248 | ||
249 | /* should not reach here */ | |
250 | while (1) | |
251 | halt(); | |
252 | } | |
253 | ||
254 | static void tboot_copy_fadt(const struct acpi_table_fadt *fadt) | |
255 | { | |
256 | #define TB_COPY_GAS(tbg, g) \ | |
257 | tbg.space_id = g.space_id; \ | |
258 | tbg.bit_width = g.bit_width; \ | |
259 | tbg.bit_offset = g.bit_offset; \ | |
260 | tbg.access_width = g.access_width; \ | |
261 | tbg.address = g.address; | |
262 | ||
263 | TB_COPY_GAS(tboot->acpi_sinfo.pm1a_cnt_blk, fadt->xpm1a_control_block); | |
264 | TB_COPY_GAS(tboot->acpi_sinfo.pm1b_cnt_blk, fadt->xpm1b_control_block); | |
265 | TB_COPY_GAS(tboot->acpi_sinfo.pm1a_evt_blk, fadt->xpm1a_event_block); | |
266 | TB_COPY_GAS(tboot->acpi_sinfo.pm1b_evt_blk, fadt->xpm1b_event_block); | |
267 | ||
268 | /* | |
269 | * We need phys addr of waking vector, but can't use virt_to_phys() on | |
270 | * &acpi_gbl_FACS because it is ioremap'ed, so calc from FACS phys | |
271 | * addr. | |
272 | */ | |
273 | tboot->acpi_sinfo.wakeup_vector = fadt->facs + | |
274 | offsetof(struct acpi_table_facs, firmware_waking_vector); | |
275 | } | |
276 | ||
a1f37788 | 277 | static int tboot_sleep(u8 sleep_state, u32 pm1a_control, u32 pm1b_control) |
31625340 JC |
278 | { |
279 | static u32 acpi_shutdown_map[ACPI_S_STATE_COUNT] = { | |
280 | /* S0,1,2: */ -1, -1, -1, | |
281 | /* S3: */ TB_SHUTDOWN_S3, | |
282 | /* S4: */ TB_SHUTDOWN_S4, | |
283 | /* S5: */ TB_SHUTDOWN_S5 }; | |
284 | ||
285 | if (!tboot_enabled()) | |
a1f37788 | 286 | return 0; |
31625340 JC |
287 | |
288 | tboot_copy_fadt(&acpi_gbl_FADT); | |
289 | tboot->acpi_sinfo.pm1a_cnt_val = pm1a_control; | |
290 | tboot->acpi_sinfo.pm1b_cnt_val = pm1b_control; | |
291 | /* we always use the 32b wakeup vector */ | |
292 | tboot->acpi_sinfo.vector_width = 32; | |
31625340 JC |
293 | |
294 | if (sleep_state >= ACPI_S_STATE_COUNT || | |
295 | acpi_shutdown_map[sleep_state] == -1) { | |
296 | pr_warning("unsupported sleep state 0x%x\n", sleep_state); | |
a1f37788 | 297 | return -1; |
31625340 JC |
298 | } |
299 | ||
300 | tboot_shutdown(acpi_shutdown_map[sleep_state]); | |
09f98a82 TL |
301 | return 0; |
302 | } | |
31625340 | 303 | |
01c6a6af BG |
304 | static int tboot_extended_sleep(u8 sleep_state, u32 val_a, u32 val_b) |
305 | { | |
306 | if (!tboot_enabled()) | |
307 | return 0; | |
308 | ||
309 | pr_warning("tboot is not able to suspend on platforms with reduced hardware sleep (ACPIv5)"); | |
310 | return -ENODEV; | |
311 | } | |
312 | ||
69575d38 SW |
313 | static atomic_t ap_wfs_count; |
314 | ||
315 | static int tboot_wait_for_aps(int num_aps) | |
31625340 JC |
316 | { |
317 | unsigned long timeout; | |
318 | ||
69575d38 SW |
319 | timeout = AP_WAIT_TIMEOUT*HZ; |
320 | while (atomic_read((atomic_t *)&tboot->num_in_wfs) != num_aps && | |
321 | timeout) { | |
322 | mdelay(1); | |
323 | timeout--; | |
324 | } | |
325 | ||
326 | if (timeout) | |
327 | pr_warning("tboot wait for APs timeout\n"); | |
328 | ||
329 | return !(atomic_read((atomic_t *)&tboot->num_in_wfs) == num_aps); | |
330 | } | |
331 | ||
148f9bb8 PG |
332 | static int tboot_cpu_callback(struct notifier_block *nfb, unsigned long action, |
333 | void *hcpu) | |
69575d38 SW |
334 | { |
335 | switch (action) { | |
336 | case CPU_DYING: | |
337 | atomic_inc(&ap_wfs_count); | |
338 | if (num_online_cpus() == 1) | |
339 | if (tboot_wait_for_aps(atomic_read(&ap_wfs_count))) | |
340 | return NOTIFY_BAD; | |
341 | break; | |
342 | } | |
343 | return NOTIFY_OK; | |
344 | } | |
345 | ||
148f9bb8 | 346 | static struct notifier_block tboot_cpu_notifier = |
69575d38 SW |
347 | { |
348 | .notifier_call = tboot_cpu_callback, | |
349 | }; | |
350 | ||
13bfd47a QR |
351 | #ifdef CONFIG_DEBUG_FS |
352 | ||
353 | #define TBOOT_LOG_UUID { 0x26, 0x25, 0x19, 0xc0, 0x30, 0x6b, 0xb4, 0x4d, \ | |
354 | 0x4c, 0x84, 0xa3, 0xe9, 0x53, 0xb8, 0x81, 0x74 } | |
355 | ||
356 | #define TBOOT_SERIAL_LOG_ADDR 0x60000 | |
357 | #define TBOOT_SERIAL_LOG_SIZE 0x08000 | |
358 | #define LOG_MAX_SIZE_OFF 16 | |
359 | #define LOG_BUF_OFF 24 | |
360 | ||
361 | static uint8_t tboot_log_uuid[16] = TBOOT_LOG_UUID; | |
362 | ||
363 | static ssize_t tboot_log_read(struct file *file, char __user *user_buf, size_t count, loff_t *ppos) | |
364 | { | |
365 | void __iomem *log_base; | |
366 | u8 log_uuid[16]; | |
367 | u32 max_size; | |
368 | void *kbuf; | |
369 | int ret = -EFAULT; | |
370 | ||
371 | log_base = ioremap_nocache(TBOOT_SERIAL_LOG_ADDR, TBOOT_SERIAL_LOG_SIZE); | |
372 | if (!log_base) | |
373 | return ret; | |
374 | ||
375 | memcpy_fromio(log_uuid, log_base, sizeof(log_uuid)); | |
376 | if (memcmp(&tboot_log_uuid, log_uuid, sizeof(log_uuid))) | |
377 | goto err_iounmap; | |
378 | ||
379 | max_size = readl(log_base + LOG_MAX_SIZE_OFF); | |
380 | if (*ppos >= max_size) { | |
381 | ret = 0; | |
382 | goto err_iounmap; | |
383 | } | |
384 | ||
385 | if (*ppos + count > max_size) | |
386 | count = max_size - *ppos; | |
387 | ||
388 | kbuf = kmalloc(count, GFP_KERNEL); | |
389 | if (!kbuf) { | |
390 | ret = -ENOMEM; | |
391 | goto err_iounmap; | |
392 | } | |
393 | ||
394 | memcpy_fromio(kbuf, log_base + LOG_BUF_OFF + *ppos, count); | |
395 | if (copy_to_user(user_buf, kbuf, count)) | |
396 | goto err_kfree; | |
397 | ||
398 | *ppos += count; | |
399 | ||
400 | ret = count; | |
401 | ||
402 | err_kfree: | |
403 | kfree(kbuf); | |
404 | ||
405 | err_iounmap: | |
406 | iounmap(log_base); | |
407 | ||
408 | return ret; | |
409 | } | |
410 | ||
411 | static const struct file_operations tboot_log_fops = { | |
412 | .read = tboot_log_read, | |
413 | .llseek = default_llseek, | |
414 | }; | |
415 | ||
416 | #endif /* CONFIG_DEBUG_FS */ | |
417 | ||
69575d38 SW |
418 | static __init int tboot_late_init(void) |
419 | { | |
31625340 JC |
420 | if (!tboot_enabled()) |
421 | return 0; | |
422 | ||
11520e5e LT |
423 | tboot_create_trampoline(); |
424 | ||
69575d38 SW |
425 | atomic_set(&ap_wfs_count, 0); |
426 | register_hotcpu_notifier(&tboot_cpu_notifier); | |
09f98a82 | 427 | |
13bfd47a QR |
428 | #ifdef CONFIG_DEBUG_FS |
429 | debugfs_create_file("tboot_log", S_IRUSR, | |
430 | arch_debugfs_dir, NULL, &tboot_log_fops); | |
431 | #endif | |
432 | ||
a1f37788 | 433 | acpi_os_set_prepare_sleep(&tboot_sleep); |
01c6a6af | 434 | acpi_os_set_prepare_extended_sleep(&tboot_extended_sleep); |
69575d38 | 435 | return 0; |
31625340 JC |
436 | } |
437 | ||
69575d38 SW |
438 | late_initcall(tboot_late_init); |
439 | ||
31625340 JC |
440 | /* |
441 | * TXT configuration registers (offsets from TXT_{PUB, PRIV}_CONFIG_REGS_BASE) | |
442 | */ | |
443 | ||
444 | #define TXT_PUB_CONFIG_REGS_BASE 0xfed30000 | |
445 | #define TXT_PRIV_CONFIG_REGS_BASE 0xfed20000 | |
446 | ||
447 | /* # pages for each config regs space - used by fixmap */ | |
448 | #define NR_TXT_CONFIG_PAGES ((TXT_PUB_CONFIG_REGS_BASE - \ | |
449 | TXT_PRIV_CONFIG_REGS_BASE) >> PAGE_SHIFT) | |
450 | ||
451 | /* offsets from pub/priv config space */ | |
452 | #define TXTCR_HEAP_BASE 0x0300 | |
453 | #define TXTCR_HEAP_SIZE 0x0308 | |
454 | ||
455 | #define SHA1_SIZE 20 | |
456 | ||
457 | struct sha1_hash { | |
458 | u8 hash[SHA1_SIZE]; | |
459 | }; | |
460 | ||
461 | struct sinit_mle_data { | |
462 | u32 version; /* currently 6 */ | |
463 | struct sha1_hash bios_acm_id; | |
464 | u32 edx_senter_flags; | |
465 | u64 mseg_valid; | |
466 | struct sha1_hash sinit_hash; | |
467 | struct sha1_hash mle_hash; | |
468 | struct sha1_hash stm_hash; | |
469 | struct sha1_hash lcp_policy_hash; | |
470 | u32 lcp_policy_control; | |
471 | u32 rlp_wakeup_addr; | |
472 | u32 reserved; | |
473 | u32 num_mdrs; | |
474 | u32 mdrs_off; | |
475 | u32 num_vtd_dmars; | |
476 | u32 vtd_dmars_off; | |
477 | } __packed; | |
478 | ||
479 | struct acpi_table_header *tboot_get_dmar_table(struct acpi_table_header *dmar_tbl) | |
480 | { | |
481 | void *heap_base, *heap_ptr, *config; | |
482 | ||
483 | if (!tboot_enabled()) | |
484 | return dmar_tbl; | |
485 | ||
486 | /* | |
487 | * ACPI tables may not be DMA protected by tboot, so use DMAR copy | |
488 | * SINIT saved in SinitMleData in TXT heap (which is DMA protected) | |
489 | */ | |
490 | ||
491 | /* map config space in order to get heap addr */ | |
492 | config = ioremap(TXT_PUB_CONFIG_REGS_BASE, NR_TXT_CONFIG_PAGES * | |
493 | PAGE_SIZE); | |
494 | if (!config) | |
495 | return NULL; | |
496 | ||
497 | /* now map TXT heap */ | |
498 | heap_base = ioremap(*(u64 *)(config + TXTCR_HEAP_BASE), | |
499 | *(u64 *)(config + TXTCR_HEAP_SIZE)); | |
500 | iounmap(config); | |
501 | if (!heap_base) | |
502 | return NULL; | |
503 | ||
504 | /* walk heap to SinitMleData */ | |
505 | /* skip BiosData */ | |
506 | heap_ptr = heap_base + *(u64 *)heap_base; | |
507 | /* skip OsMleData */ | |
508 | heap_ptr += *(u64 *)heap_ptr; | |
509 | /* skip OsSinitData */ | |
510 | heap_ptr += *(u64 *)heap_ptr; | |
511 | /* now points to SinitMleDataSize; set to SinitMleData */ | |
512 | heap_ptr += sizeof(u64); | |
513 | /* get addr of DMAR table */ | |
514 | dmar_tbl = (struct acpi_table_header *)(heap_ptr + | |
515 | ((struct sinit_mle_data *)heap_ptr)->vtd_dmars_off - | |
516 | sizeof(u64)); | |
517 | ||
518 | /* don't unmap heap because dmar.c needs access to this */ | |
519 | ||
520 | return dmar_tbl; | |
521 | } | |
522 | ||
523 | int tboot_force_iommu(void) | |
524 | { | |
525 | if (!tboot_enabled()) | |
526 | return 0; | |
527 | ||
528 | if (no_iommu || swiotlb || dmar_disabled) | |
529 | pr_warning("Forcing Intel-IOMMU to enabled\n"); | |
530 | ||
531 | dmar_disabled = 0; | |
532 | #ifdef CONFIG_SWIOTLB | |
533 | swiotlb = 0; | |
534 | #endif | |
535 | no_iommu = 0; | |
536 | ||
537 | return 1; | |
538 | } |