Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc-2.6
[linux-2.6.git] / arch / x86 / kernel / tboot.c
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. */
48 struct 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
56 static u8 tboot_uuid[16] __initdata = TBOOT_UUID;
57
58 void __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
103 static pgd_t *tboot_pg_dir;
104 static 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
115 static inline void switch_to_tboot_pt(void)
116 {
117         write_cr3(virt_to_phys(tboot_pg_dir));
118 }
119
120 static 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
143 static 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
159 static 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
173 static 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
185 static 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
207 static 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
216 void 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
248 static 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
271 void 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
297 static atomic_t ap_wfs_count;
298
299 static 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
316 static 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
330 static struct notifier_block tboot_cpu_notifier __cpuinitdata =
331 {
332         .notifier_call = tboot_cpu_callback,
333 };
334
335 static __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
347 late_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
366 struct sha1_hash {
367         u8 hash[SHA1_SIZE];
368 };
369
370 struct 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
388 struct 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
432 int 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 }