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-rw-r--r--arch/x86/Kconfig4
-rw-r--r--arch/x86/include/asm/bootparam.h3
-rw-r--r--arch/x86/include/asm/fixmap.h3
-rw-r--r--arch/x86/kernel/Makefile1
-rw-r--r--arch/x86/kernel/reboot.c7
-rw-r--r--arch/x86/kernel/setup.c3
-rw-r--r--arch/x86/kernel/smpboot.c2
-rw-r--r--arch/x86/kernel/tboot.c447
8 files changed, 469 insertions, 1 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index fc20fdc0f7f2..74bf3e30ce75 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -179,6 +179,10 @@ config ARCH_SUPPORTS_OPTIMIZED_INLINING
179config ARCH_SUPPORTS_DEBUG_PAGEALLOC 179config ARCH_SUPPORTS_DEBUG_PAGEALLOC
180 def_bool y 180 def_bool y
181 181
182config HAVE_INTEL_TXT
183 def_bool y
184 depends on EXPERIMENTAL && DMAR && ACPI
185
182# Use the generic interrupt handling code in kernel/irq/: 186# Use the generic interrupt handling code in kernel/irq/:
183config GENERIC_HARDIRQS 187config GENERIC_HARDIRQS
184 bool 188 bool
diff --git a/arch/x86/include/asm/bootparam.h b/arch/x86/include/asm/bootparam.h
index 1724e8de317c..6ca20218dd72 100644
--- a/arch/x86/include/asm/bootparam.h
+++ b/arch/x86/include/asm/bootparam.h
@@ -85,7 +85,8 @@ struct efi_info {
85struct boot_params { 85struct boot_params {
86 struct screen_info screen_info; /* 0x000 */ 86 struct screen_info screen_info; /* 0x000 */
87 struct apm_bios_info apm_bios_info; /* 0x040 */ 87 struct apm_bios_info apm_bios_info; /* 0x040 */
88 __u8 _pad2[12]; /* 0x054 */ 88 __u8 _pad2[4]; /* 0x054 */
89 __u64 tboot_addr; /* 0x058 */
89 struct ist_info ist_info; /* 0x060 */ 90 struct ist_info ist_info; /* 0x060 */
90 __u8 _pad3[16]; /* 0x070 */ 91 __u8 _pad3[16]; /* 0x070 */
91 __u8 hd0_info[16]; /* obsolete! */ /* 0x080 */ 92 __u8 hd0_info[16]; /* obsolete! */ /* 0x080 */
diff --git a/arch/x86/include/asm/fixmap.h b/arch/x86/include/asm/fixmap.h
index 7b2d71df39a6..14f9890eb495 100644
--- a/arch/x86/include/asm/fixmap.h
+++ b/arch/x86/include/asm/fixmap.h
@@ -132,6 +132,9 @@ enum fixed_addresses {
132#ifdef CONFIG_X86_32 132#ifdef CONFIG_X86_32
133 FIX_WP_TEST, 133 FIX_WP_TEST,
134#endif 134#endif
135#ifdef CONFIG_INTEL_TXT
136 FIX_TBOOT_BASE,
137#endif
135 __end_of_fixed_addresses 138 __end_of_fixed_addresses
136}; 139};
137 140
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index 430d5b24af7b..832cb838cb48 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -52,6 +52,7 @@ obj-$(CONFIG_X86_DS_SELFTEST) += ds_selftest.o
52obj-$(CONFIG_X86_32) += tls.o 52obj-$(CONFIG_X86_32) += tls.o
53obj-$(CONFIG_IA32_EMULATION) += tls.o 53obj-$(CONFIG_IA32_EMULATION) += tls.o
54obj-y += step.o 54obj-y += step.o
55obj-$(CONFIG_INTEL_TXT) += tboot.o
55obj-$(CONFIG_STACKTRACE) += stacktrace.o 56obj-$(CONFIG_STACKTRACE) += stacktrace.o
56obj-y += cpu/ 57obj-y += cpu/
57obj-y += acpi/ 58obj-y += acpi/
diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c
index a06e8d101844..27349f92a6d7 100644
--- a/arch/x86/kernel/reboot.c
+++ b/arch/x86/kernel/reboot.c
@@ -4,6 +4,7 @@
4#include <linux/pm.h> 4#include <linux/pm.h>
5#include <linux/efi.h> 5#include <linux/efi.h>
6#include <linux/dmi.h> 6#include <linux/dmi.h>
7#include <linux/tboot.h>
7#include <acpi/reboot.h> 8#include <acpi/reboot.h>
8#include <asm/io.h> 9#include <asm/io.h>
9#include <asm/apic.h> 10#include <asm/apic.h>
@@ -508,6 +509,8 @@ static void native_machine_emergency_restart(void)
508 if (reboot_emergency) 509 if (reboot_emergency)
509 emergency_vmx_disable_all(); 510 emergency_vmx_disable_all();
510 511
512 tboot_shutdown(TB_SHUTDOWN_REBOOT);
513
511 /* Tell the BIOS if we want cold or warm reboot */ 514 /* Tell the BIOS if we want cold or warm reboot */
512 *((unsigned short *)__va(0x472)) = reboot_mode; 515 *((unsigned short *)__va(0x472)) = reboot_mode;
513 516
@@ -634,6 +637,8 @@ static void native_machine_halt(void)
634 /* stop other cpus and apics */ 637 /* stop other cpus and apics */
635 machine_shutdown(); 638 machine_shutdown();
636 639
640 tboot_shutdown(TB_SHUTDOWN_HALT);
641
637 /* stop this cpu */ 642 /* stop this cpu */
638 stop_this_cpu(NULL); 643 stop_this_cpu(NULL);
639} 644}
@@ -645,6 +650,8 @@ static void native_machine_power_off(void)
645 machine_shutdown(); 650 machine_shutdown();
646 pm_power_off(); 651 pm_power_off();
647 } 652 }
653 /* a fallback in case there is no PM info available */
654 tboot_shutdown(TB_SHUTDOWN_HALT);
648} 655}
649 656
650struct machine_ops machine_ops = { 657struct machine_ops machine_ops = {
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 63f32d220ef2..61f86f241420 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -66,6 +66,7 @@
66 66
67#include <linux/percpu.h> 67#include <linux/percpu.h>
68#include <linux/crash_dump.h> 68#include <linux/crash_dump.h>
69#include <linux/tboot.h>
69 70
70#include <video/edid.h> 71#include <video/edid.h>
71 72
@@ -977,6 +978,8 @@ void __init setup_arch(char **cmdline_p)
977 paravirt_pagetable_setup_done(swapper_pg_dir); 978 paravirt_pagetable_setup_done(swapper_pg_dir);
978 paravirt_post_allocator_init(); 979 paravirt_post_allocator_init();
979 980
981 tboot_probe();
982
980#ifdef CONFIG_X86_64 983#ifdef CONFIG_X86_64
981 map_vsyscall(); 984 map_vsyscall();
982#endif 985#endif
diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c
index c36cc1452cdc..9d8319183aae 100644
--- a/arch/x86/kernel/smpboot.c
+++ b/arch/x86/kernel/smpboot.c
@@ -47,6 +47,7 @@
47#include <linux/bootmem.h> 47#include <linux/bootmem.h>
48#include <linux/err.h> 48#include <linux/err.h>
49#include <linux/nmi.h> 49#include <linux/nmi.h>
50#include <linux/tboot.h>
50 51
51#include <asm/acpi.h> 52#include <asm/acpi.h>
52#include <asm/desc.h> 53#include <asm/desc.h>
@@ -1318,6 +1319,7 @@ void play_dead_common(void)
1318void native_play_dead(void) 1319void native_play_dead(void)
1319{ 1320{
1320 play_dead_common(); 1321 play_dead_common();
1322 tboot_shutdown(TB_SHUTDOWN_WFS);
1321 wbinvd_halt(); 1323 wbinvd_halt();
1322} 1324}
1323 1325
diff --git a/arch/x86/kernel/tboot.c b/arch/x86/kernel/tboot.c
new file mode 100644
index 000000000000..86c9f91b48ae
--- /dev/null
+++ b/arch/x86/kernel/tboot.c
@@ -0,0 +1,447 @@
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>
25#include <linux/delay.h>
26#include <linux/sched.h>
27#include <linux/init.h>
28#include <linux/dmar.h>
29#include <linux/cpu.h>
30#include <linux/pfn.h>
31#include <linux/mm.h>
32#include <linux/tboot.h>
33
34#include <asm/trampoline.h>
35#include <asm/processor.h>
36#include <asm/bootparam.h>
37#include <asm/pgtable.h>
38#include <asm/pgalloc.h>
39#include <asm/fixmap.h>
40#include <asm/proto.h>
41#include <asm/setup.h>
42#include <asm/e820.h>
43#include <asm/io.h>
44
45#include "acpi/realmode/wakeup.h"
46
47/* Global pointer to shared data; NULL means no measured launch. */
48struct tboot *tboot __read_mostly;
49
50/* timeout for APs (in secs) to enter wait-for-SIPI state during shutdown */
51#define AP_WAIT_TIMEOUT 1
52
53#undef pr_fmt
54#define pr_fmt(fmt) "tboot: " fmt
55
56static u8 tboot_uuid[16] __initdata = TBOOT_UUID;
57
58void __init tboot_probe(void)
59{
60 /* Look for valid page-aligned address for shared page. */
61 if (!boot_params.tboot_addr)
62 return;
63 /*
64 * also verify that it is mapped as we expect it before calling
65 * set_fixmap(), to reduce chance of garbage value causing crash
66 */
67 if (!e820_any_mapped(boot_params.tboot_addr,
68 boot_params.tboot_addr, E820_RESERVED)) {
69 pr_warning("non-0 tboot_addr but it is not of type E820_RESERVED\n");
70 return;
71 }
72
73 /* only a natively booted kernel should be using TXT */
74 if (paravirt_enabled()) {
75 pr_warning("non-0 tboot_addr but pv_ops is enabled\n");
76 return;
77 }
78
79 /* Map and check for tboot UUID. */
80 set_fixmap(FIX_TBOOT_BASE, boot_params.tboot_addr);
81 tboot = (struct tboot *)fix_to_virt(FIX_TBOOT_BASE);
82 if (memcmp(&tboot_uuid, &tboot->uuid, sizeof(tboot->uuid))) {
83 pr_warning("tboot at 0x%llx is invalid\n",
84 boot_params.tboot_addr);
85 tboot = NULL;
86 return;
87 }
88 if (tboot->version < 5) {
89 pr_warning("tboot version is invalid: %u\n", tboot->version);
90 tboot = NULL;
91 return;
92 }
93
94 pr_info("found shared page at phys addr 0x%llx:\n",
95 boot_params.tboot_addr);
96 pr_debug("version: %d\n", tboot->version);
97 pr_debug("log_addr: 0x%08x\n", tboot->log_addr);
98 pr_debug("shutdown_entry: 0x%x\n", tboot->shutdown_entry);
99 pr_debug("tboot_base: 0x%08x\n", tboot->tboot_base);
100 pr_debug("tboot_size: 0x%x\n", tboot->tboot_size);
101}
102
103static pgd_t *tboot_pg_dir;
104static struct mm_struct tboot_mm = {
105 .mm_rb = RB_ROOT,
106 .pgd = swapper_pg_dir,
107 .mm_users = ATOMIC_INIT(2),
108 .mm_count = ATOMIC_INIT(1),
109 .mmap_sem = __RWSEM_INITIALIZER(init_mm.mmap_sem),
110 .page_table_lock = __SPIN_LOCK_UNLOCKED(init_mm.page_table_lock),
111 .mmlist = LIST_HEAD_INIT(init_mm.mmlist),
112 .cpu_vm_mask = CPU_MASK_ALL,
113};
114
115static inline void switch_to_tboot_pt(void)
116{
117 write_cr3(virt_to_phys(tboot_pg_dir));
118}
119
120static int map_tboot_page(unsigned long vaddr, unsigned long pfn,
121 pgprot_t prot)
122{
123 pgd_t *pgd;
124 pud_t *pud;
125 pmd_t *pmd;
126 pte_t *pte;
127
128 pgd = pgd_offset(&tboot_mm, vaddr);
129 pud = pud_alloc(&tboot_mm, pgd, vaddr);
130 if (!pud)
131 return -1;
132 pmd = pmd_alloc(&tboot_mm, pud, vaddr);
133 if (!pmd)
134 return -1;
135 pte = pte_alloc_map(&tboot_mm, pmd, vaddr);
136 if (!pte)
137 return -1;
138 set_pte_at(&tboot_mm, vaddr, pte, pfn_pte(pfn, prot));
139 pte_unmap(pte);
140 return 0;
141}
142
143static int map_tboot_pages(unsigned long vaddr, unsigned long start_pfn,
144 unsigned long nr)
145{
146 /* Reuse the original kernel mapping */
147 tboot_pg_dir = pgd_alloc(&tboot_mm);
148 if (!tboot_pg_dir)
149 return -1;
150
151 for (; nr > 0; nr--, vaddr += PAGE_SIZE, start_pfn++) {
152 if (map_tboot_page(vaddr, start_pfn, PAGE_KERNEL_EXEC))
153 return -1;
154 }
155
156 return 0;
157}
158
159static void tboot_create_trampoline(void)
160{
161 u32 map_base, map_size;
162
163 /* Create identity map for tboot shutdown code. */
164 map_base = PFN_DOWN(tboot->tboot_base);
165 map_size = PFN_UP(tboot->tboot_size);
166 if (map_tboot_pages(map_base << PAGE_SHIFT, map_base, map_size))
167 panic("tboot: Error mapping tboot pages (mfns) @ 0x%x, 0x%x\n",
168 map_base, map_size);
169}
170
171#ifdef CONFIG_ACPI_SLEEP
172
173static void add_mac_region(phys_addr_t start, unsigned long size)
174{
175 struct tboot_mac_region *mr;
176 phys_addr_t end = start + size;
177
178 if (start && size) {
179 mr = &tboot->mac_regions[tboot->num_mac_regions++];
180 mr->start = round_down(start, PAGE_SIZE);
181 mr->size = round_up(end, PAGE_SIZE) - mr->start;
182 }
183}
184
185static int tboot_setup_sleep(void)
186{
187 tboot->num_mac_regions = 0;
188
189 /* S3 resume code */
190 add_mac_region(acpi_wakeup_address, WAKEUP_SIZE);
191
192#ifdef CONFIG_X86_TRAMPOLINE
193 /* AP trampoline code */
194 add_mac_region(virt_to_phys(trampoline_base), TRAMPOLINE_SIZE);
195#endif
196
197 /* kernel code + data + bss */
198 add_mac_region(virt_to_phys(_text), _end - _text);
199
200 tboot->acpi_sinfo.kernel_s3_resume_vector = acpi_wakeup_address;
201
202 return 0;
203}
204
205#else /* no CONFIG_ACPI_SLEEP */
206
207static int tboot_setup_sleep(void)
208{
209 /* S3 shutdown requested, but S3 not supported by the kernel... */
210 BUG();
211 return -1;
212}
213
214#endif
215
216void tboot_shutdown(u32 shutdown_type)
217{
218 void (*shutdown)(void);
219
220 if (!tboot_enabled())
221 return;
222
223 /*
224 * if we're being called before the 1:1 mapping is set up then just
225 * return and let the normal shutdown happen; this should only be
226 * due to very early panic()
227 */
228 if (!tboot_pg_dir)
229 return;
230
231 /* if this is S3 then set regions to MAC */
232 if (shutdown_type == TB_SHUTDOWN_S3)
233 if (tboot_setup_sleep())
234 return;
235
236 tboot->shutdown_type = shutdown_type;
237
238 switch_to_tboot_pt();
239
240 shutdown = (void(*)(void))(unsigned long)tboot->shutdown_entry;
241 shutdown();
242
243 /* should not reach here */
244 while (1)
245 halt();
246}
247
248static void tboot_copy_fadt(const struct acpi_table_fadt *fadt)
249{
250#define TB_COPY_GAS(tbg, g) \
251 tbg.space_id = g.space_id; \
252 tbg.bit_width = g.bit_width; \
253 tbg.bit_offset = g.bit_offset; \
254 tbg.access_width = g.access_width; \
255 tbg.address = g.address;
256
257 TB_COPY_GAS(tboot->acpi_sinfo.pm1a_cnt_blk, fadt->xpm1a_control_block);
258 TB_COPY_GAS(tboot->acpi_sinfo.pm1b_cnt_blk, fadt->xpm1b_control_block);
259 TB_COPY_GAS(tboot->acpi_sinfo.pm1a_evt_blk, fadt->xpm1a_event_block);
260 TB_COPY_GAS(tboot->acpi_sinfo.pm1b_evt_blk, fadt->xpm1b_event_block);
261
262 /*
263 * We need phys addr of waking vector, but can't use virt_to_phys() on
264 * &acpi_gbl_FACS because it is ioremap'ed, so calc from FACS phys
265 * addr.
266 */
267 tboot->acpi_sinfo.wakeup_vector = fadt->facs +
268 offsetof(struct acpi_table_facs, firmware_waking_vector);
269}
270
271void tboot_sleep(u8 sleep_state, u32 pm1a_control, u32 pm1b_control)
272{
273 static u32 acpi_shutdown_map[ACPI_S_STATE_COUNT] = {
274 /* S0,1,2: */ -1, -1, -1,
275 /* S3: */ TB_SHUTDOWN_S3,
276 /* S4: */ TB_SHUTDOWN_S4,
277 /* S5: */ TB_SHUTDOWN_S5 };
278
279 if (!tboot_enabled())
280 return;
281
282 tboot_copy_fadt(&acpi_gbl_FADT);
283 tboot->acpi_sinfo.pm1a_cnt_val = pm1a_control;
284 tboot->acpi_sinfo.pm1b_cnt_val = pm1b_control;
285 /* we always use the 32b wakeup vector */
286 tboot->acpi_sinfo.vector_width = 32;
287
288 if (sleep_state >= ACPI_S_STATE_COUNT ||
289 acpi_shutdown_map[sleep_state] == -1) {
290 pr_warning("unsupported sleep state 0x%x\n", sleep_state);
291 return;
292 }
293
294 tboot_shutdown(acpi_shutdown_map[sleep_state]);
295}
296
297static atomic_t ap_wfs_count;
298
299static int tboot_wait_for_aps(int num_aps)
300{
301 unsigned long timeout;
302
303 timeout = AP_WAIT_TIMEOUT*HZ;
304 while (atomic_read((atomic_t *)&tboot->num_in_wfs) != num_aps &&
305 timeout) {
306 mdelay(1);
307 timeout--;
308 }
309
310 if (timeout)
311 pr_warning("tboot wait for APs timeout\n");
312
313 return !(atomic_read((atomic_t *)&tboot->num_in_wfs) == num_aps);
314}
315
316static int __cpuinit tboot_cpu_callback(struct notifier_block *nfb,
317 unsigned long action, void *hcpu)
318{
319 switch (action) {
320 case CPU_DYING:
321 atomic_inc(&ap_wfs_count);
322 if (num_online_cpus() == 1)
323 if (tboot_wait_for_aps(atomic_read(&ap_wfs_count)))
324 return NOTIFY_BAD;
325 break;
326 }
327 return NOTIFY_OK;
328}
329
330static struct notifier_block tboot_cpu_notifier __cpuinitdata =
331{
332 .notifier_call = tboot_cpu_callback,
333};
334
335static __init int tboot_late_init(void)
336{
337 if (!tboot_enabled())
338 return 0;
339
340 tboot_create_trampoline();
341
342 atomic_set(&ap_wfs_count, 0);
343 register_hotcpu_notifier(&tboot_cpu_notifier);
344 return 0;
345}
346
347late_initcall(tboot_late_init);
348
349/*
350 * TXT configuration registers (offsets from TXT_{PUB, PRIV}_CONFIG_REGS_BASE)
351 */
352
353#define TXT_PUB_CONFIG_REGS_BASE 0xfed30000
354#define TXT_PRIV_CONFIG_REGS_BASE 0xfed20000
355
356/* # pages for each config regs space - used by fixmap */
357#define NR_TXT_CONFIG_PAGES ((TXT_PUB_CONFIG_REGS_BASE - \
358 TXT_PRIV_CONFIG_REGS_BASE) >> PAGE_SHIFT)
359
360/* offsets from pub/priv config space */
361#define TXTCR_HEAP_BASE 0x0300
362#define TXTCR_HEAP_SIZE 0x0308
363
364#define SHA1_SIZE 20
365
366struct sha1_hash {
367 u8 hash[SHA1_SIZE];
368};
369
370struct sinit_mle_data {
371 u32 version; /* currently 6 */
372 struct sha1_hash bios_acm_id;
373 u32 edx_senter_flags;
374 u64 mseg_valid;
375 struct sha1_hash sinit_hash;
376 struct sha1_hash mle_hash;
377 struct sha1_hash stm_hash;
378 struct sha1_hash lcp_policy_hash;
379 u32 lcp_policy_control;
380 u32 rlp_wakeup_addr;
381 u32 reserved;
382 u32 num_mdrs;
383 u32 mdrs_off;
384 u32 num_vtd_dmars;
385 u32 vtd_dmars_off;
386} __packed;
387
388struct acpi_table_header *tboot_get_dmar_table(struct acpi_table_header *dmar_tbl)
389{
390 void *heap_base, *heap_ptr, *config;
391
392 if (!tboot_enabled())
393 return dmar_tbl;
394
395 /*
396 * ACPI tables may not be DMA protected by tboot, so use DMAR copy
397 * SINIT saved in SinitMleData in TXT heap (which is DMA protected)
398 */
399
400 /* map config space in order to get heap addr */
401 config = ioremap(TXT_PUB_CONFIG_REGS_BASE, NR_TXT_CONFIG_PAGES *
402 PAGE_SIZE);
403 if (!config)
404 return NULL;
405
406 /* now map TXT heap */
407 heap_base = ioremap(*(u64 *)(config + TXTCR_HEAP_BASE),
408 *(u64 *)(config + TXTCR_HEAP_SIZE));
409 iounmap(config);
410 if (!heap_base)
411 return NULL;
412
413 /* walk heap to SinitMleData */
414 /* skip BiosData */
415 heap_ptr = heap_base + *(u64 *)heap_base;
416 /* skip OsMleData */
417 heap_ptr += *(u64 *)heap_ptr;
418 /* skip OsSinitData */
419 heap_ptr += *(u64 *)heap_ptr;
420 /* now points to SinitMleDataSize; set to SinitMleData */
421 heap_ptr += sizeof(u64);
422 /* get addr of DMAR table */
423 dmar_tbl = (struct acpi_table_header *)(heap_ptr +
424 ((struct sinit_mle_data *)heap_ptr)->vtd_dmars_off -
425 sizeof(u64));
426
427 /* don't unmap heap because dmar.c needs access to this */
428
429 return dmar_tbl;
430}
431
432int tboot_force_iommu(void)
433{
434 if (!tboot_enabled())
435 return 0;
436
437 if (no_iommu || swiotlb || dmar_disabled)
438 pr_warning("Forcing Intel-IOMMU to enabled\n");
439
440 dmar_disabled = 0;
441#ifdef CONFIG_SWIOTLB
442 swiotlb = 0;
443#endif
444 no_iommu = 0;
445
446 return 1;
447}