]> git.openfabrics.org - ~shefty/rdma-dev.git/blob - arch/x86/kernel/tboot.c
Merge branch 'tboot' into release
[~shefty/rdma-dev.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/export.h>
26 #include <linux/delay.h>
27 #include <linux/sched.h>
28 #include <linux/init.h>
29 #include <linux/dmar.h>
30 #include <linux/cpu.h>
31 #include <linux/pfn.h>
32 #include <linux/mm.h>
33 #include <linux/tboot.h>
34
35 #include <asm/trampoline.h>
36 #include <asm/processor.h>
37 #include <asm/bootparam.h>
38 #include <asm/pgtable.h>
39 #include <asm/pgalloc.h>
40 #include <asm/swiotlb.h>
41 #include <asm/fixmap.h>
42 #include <asm/proto.h>
43 #include <asm/setup.h>
44 #include <asm/e820.h>
45 #include <asm/io.h>
46
47 #include "acpi/realmode/wakeup.h"
48
49 /* Global pointer to shared data; NULL means no measured launch. */
50 struct tboot *tboot __read_mostly;
51 EXPORT_SYMBOL(tboot);
52
53 /* timeout for APs (in secs) to enter wait-for-SIPI state during shutdown */
54 #define AP_WAIT_TIMEOUT         1
55
56 #undef pr_fmt
57 #define pr_fmt(fmt)     "tboot: " fmt
58
59 static u8 tboot_uuid[16] __initdata = TBOOT_UUID;
60
61 void __init tboot_probe(void)
62 {
63         /* Look for valid page-aligned address for shared page. */
64         if (!boot_params.tboot_addr)
65                 return;
66         /*
67          * also verify that it is mapped as we expect it before calling
68          * set_fixmap(), to reduce chance of garbage value causing crash
69          */
70         if (!e820_any_mapped(boot_params.tboot_addr,
71                              boot_params.tboot_addr, E820_RESERVED)) {
72                 pr_warning("non-0 tboot_addr but it is not of type E820_RESERVED\n");
73                 return;
74         }
75
76         /* only a natively booted kernel should be using TXT */
77         if (paravirt_enabled()) {
78                 pr_warning("non-0 tboot_addr but pv_ops is enabled\n");
79                 return;
80         }
81
82         /* Map and check for tboot UUID. */
83         set_fixmap(FIX_TBOOT_BASE, boot_params.tboot_addr);
84         tboot = (struct tboot *)fix_to_virt(FIX_TBOOT_BASE);
85         if (memcmp(&tboot_uuid, &tboot->uuid, sizeof(tboot->uuid))) {
86                 pr_warning("tboot at 0x%llx is invalid\n",
87                            boot_params.tboot_addr);
88                 tboot = NULL;
89                 return;
90         }
91         if (tboot->version < 5) {
92                 pr_warning("tboot version is invalid: %u\n", tboot->version);
93                 tboot = NULL;
94                 return;
95         }
96
97         pr_info("found shared page at phys addr 0x%llx:\n",
98                 boot_params.tboot_addr);
99         pr_debug("version: %d\n", tboot->version);
100         pr_debug("log_addr: 0x%08x\n", tboot->log_addr);
101         pr_debug("shutdown_entry: 0x%x\n", tboot->shutdown_entry);
102         pr_debug("tboot_base: 0x%08x\n", tboot->tboot_base);
103         pr_debug("tboot_size: 0x%x\n", tboot->tboot_size);
104 }
105
106 static pgd_t *tboot_pg_dir;
107 static struct mm_struct tboot_mm = {
108         .mm_rb          = RB_ROOT,
109         .pgd            = swapper_pg_dir,
110         .mm_users       = ATOMIC_INIT(2),
111         .mm_count       = ATOMIC_INIT(1),
112         .mmap_sem       = __RWSEM_INITIALIZER(init_mm.mmap_sem),
113         .page_table_lock =  __SPIN_LOCK_UNLOCKED(init_mm.page_table_lock),
114         .mmlist         = LIST_HEAD_INIT(init_mm.mmlist),
115 };
116
117 static inline void switch_to_tboot_pt(void)
118 {
119         write_cr3(virt_to_phys(tboot_pg_dir));
120 }
121
122 static int map_tboot_page(unsigned long vaddr, unsigned long pfn,
123                           pgprot_t prot)
124 {
125         pgd_t *pgd;
126         pud_t *pud;
127         pmd_t *pmd;
128         pte_t *pte;
129
130         pgd = pgd_offset(&tboot_mm, vaddr);
131         pud = pud_alloc(&tboot_mm, pgd, vaddr);
132         if (!pud)
133                 return -1;
134         pmd = pmd_alloc(&tboot_mm, pud, vaddr);
135         if (!pmd)
136                 return -1;
137         pte = pte_alloc_map(&tboot_mm, NULL, pmd, vaddr);
138         if (!pte)
139                 return -1;
140         set_pte_at(&tboot_mm, vaddr, pte, pfn_pte(pfn, prot));
141         pte_unmap(pte);
142         return 0;
143 }
144
145 static int map_tboot_pages(unsigned long vaddr, unsigned long start_pfn,
146                            unsigned long nr)
147 {
148         /* Reuse the original kernel mapping */
149         tboot_pg_dir = pgd_alloc(&tboot_mm);
150         if (!tboot_pg_dir)
151                 return -1;
152
153         for (; nr > 0; nr--, vaddr += PAGE_SIZE, start_pfn++) {
154                 if (map_tboot_page(vaddr, start_pfn, PAGE_KERNEL_EXEC))
155                         return -1;
156         }
157
158         return 0;
159 }
160
161 static void tboot_create_trampoline(void)
162 {
163         u32 map_base, map_size;
164
165         /* Create identity map for tboot shutdown code. */
166         map_base = PFN_DOWN(tboot->tboot_base);
167         map_size = PFN_UP(tboot->tboot_size);
168         if (map_tboot_pages(map_base << PAGE_SHIFT, map_base, map_size))
169                 panic("tboot: Error mapping tboot pages (mfns) @ 0x%x, 0x%x\n",
170                       map_base, map_size);
171 }
172
173 #ifdef CONFIG_ACPI_SLEEP
174
175 static void add_mac_region(phys_addr_t start, unsigned long size)
176 {
177         struct tboot_mac_region *mr;
178         phys_addr_t end = start + size;
179
180         if (tboot->num_mac_regions >= MAX_TB_MAC_REGIONS)
181                 panic("tboot: Too many MAC regions\n");
182
183         if (start && size) {
184                 mr = &tboot->mac_regions[tboot->num_mac_regions++];
185                 mr->start = round_down(start, PAGE_SIZE);
186                 mr->size  = round_up(end, PAGE_SIZE) - mr->start;
187         }
188 }
189
190 static int tboot_setup_sleep(void)
191 {
192         int i;
193
194         tboot->num_mac_regions = 0;
195
196         for (i = 0; i < e820.nr_map; i++) {
197                 if ((e820.map[i].type != E820_RAM)
198                  && (e820.map[i].type != E820_RESERVED_KERN))
199                         continue;
200
201                 add_mac_region(e820.map[i].addr, e820.map[i].size);
202         }
203
204         tboot->acpi_sinfo.kernel_s3_resume_vector = acpi_wakeup_address;
205
206         return 0;
207 }
208
209 #else /* no CONFIG_ACPI_SLEEP */
210
211 static int tboot_setup_sleep(void)
212 {
213         /* S3 shutdown requested, but S3 not supported by the kernel... */
214         BUG();
215         return -1;
216 }
217
218 #endif
219
220 void tboot_shutdown(u32 shutdown_type)
221 {
222         void (*shutdown)(void);
223
224         if (!tboot_enabled())
225                 return;
226
227         /*
228          * if we're being called before the 1:1 mapping is set up then just
229          * return and let the normal shutdown happen; this should only be
230          * due to very early panic()
231          */
232         if (!tboot_pg_dir)
233                 return;
234
235         /* if this is S3 then set regions to MAC */
236         if (shutdown_type == TB_SHUTDOWN_S3)
237                 if (tboot_setup_sleep())
238                         return;
239
240         tboot->shutdown_type = shutdown_type;
241
242         switch_to_tboot_pt();
243
244         shutdown = (void(*)(void))(unsigned long)tboot->shutdown_entry;
245         shutdown();
246
247         /* should not reach here */
248         while (1)
249                 halt();
250 }
251
252 static void tboot_copy_fadt(const struct acpi_table_fadt *fadt)
253 {
254 #define TB_COPY_GAS(tbg, g)                     \
255         tbg.space_id     = g.space_id;          \
256         tbg.bit_width    = g.bit_width;         \
257         tbg.bit_offset   = g.bit_offset;        \
258         tbg.access_width = g.access_width;      \
259         tbg.address      = g.address;
260
261         TB_COPY_GAS(tboot->acpi_sinfo.pm1a_cnt_blk, fadt->xpm1a_control_block);
262         TB_COPY_GAS(tboot->acpi_sinfo.pm1b_cnt_blk, fadt->xpm1b_control_block);
263         TB_COPY_GAS(tboot->acpi_sinfo.pm1a_evt_blk, fadt->xpm1a_event_block);
264         TB_COPY_GAS(tboot->acpi_sinfo.pm1b_evt_blk, fadt->xpm1b_event_block);
265
266         /*
267          * We need phys addr of waking vector, but can't use virt_to_phys() on
268          * &acpi_gbl_FACS because it is ioremap'ed, so calc from FACS phys
269          * addr.
270          */
271         tboot->acpi_sinfo.wakeup_vector = fadt->facs +
272                 offsetof(struct acpi_table_facs, firmware_waking_vector);
273 }
274
275 static int tboot_sleep(u8 sleep_state, u32 pm1a_control, u32 pm1b_control)
276 {
277         static u32 acpi_shutdown_map[ACPI_S_STATE_COUNT] = {
278                 /* S0,1,2: */ -1, -1, -1,
279                 /* S3: */ TB_SHUTDOWN_S3,
280                 /* S4: */ TB_SHUTDOWN_S4,
281                 /* S5: */ TB_SHUTDOWN_S5 };
282
283         if (!tboot_enabled())
284                 return 0;
285
286         tboot_copy_fadt(&acpi_gbl_FADT);
287         tboot->acpi_sinfo.pm1a_cnt_val = pm1a_control;
288         tboot->acpi_sinfo.pm1b_cnt_val = pm1b_control;
289         /* we always use the 32b wakeup vector */
290         tboot->acpi_sinfo.vector_width = 32;
291
292         if (sleep_state >= ACPI_S_STATE_COUNT ||
293             acpi_shutdown_map[sleep_state] == -1) {
294                 pr_warning("unsupported sleep state 0x%x\n", sleep_state);
295                 return -1;
296         }
297
298         tboot_shutdown(acpi_shutdown_map[sleep_state]);
299         return 0;
300 }
301
302 static atomic_t ap_wfs_count;
303
304 static int tboot_wait_for_aps(int num_aps)
305 {
306         unsigned long timeout;
307
308         timeout = AP_WAIT_TIMEOUT*HZ;
309         while (atomic_read((atomic_t *)&tboot->num_in_wfs) != num_aps &&
310                timeout) {
311                 mdelay(1);
312                 timeout--;
313         }
314
315         if (timeout)
316                 pr_warning("tboot wait for APs timeout\n");
317
318         return !(atomic_read((atomic_t *)&tboot->num_in_wfs) == num_aps);
319 }
320
321 static int __cpuinit tboot_cpu_callback(struct notifier_block *nfb,
322                         unsigned long action, void *hcpu)
323 {
324         switch (action) {
325         case CPU_DYING:
326                 atomic_inc(&ap_wfs_count);
327                 if (num_online_cpus() == 1)
328                         if (tboot_wait_for_aps(atomic_read(&ap_wfs_count)))
329                                 return NOTIFY_BAD;
330                 break;
331         }
332         return NOTIFY_OK;
333 }
334
335 static struct notifier_block tboot_cpu_notifier __cpuinitdata =
336 {
337         .notifier_call = tboot_cpu_callback,
338 };
339
340 static __init int tboot_late_init(void)
341 {
342         if (!tboot_enabled())
343                 return 0;
344
345         tboot_create_trampoline();
346
347         atomic_set(&ap_wfs_count, 0);
348         register_hotcpu_notifier(&tboot_cpu_notifier);
349
350         acpi_os_set_prepare_sleep(&tboot_sleep);
351         return 0;
352 }
353
354 late_initcall(tboot_late_init);
355
356 /*
357  * TXT configuration registers (offsets from TXT_{PUB, PRIV}_CONFIG_REGS_BASE)
358  */
359
360 #define TXT_PUB_CONFIG_REGS_BASE       0xfed30000
361 #define TXT_PRIV_CONFIG_REGS_BASE      0xfed20000
362
363 /* # pages for each config regs space - used by fixmap */
364 #define NR_TXT_CONFIG_PAGES     ((TXT_PUB_CONFIG_REGS_BASE -                \
365                                   TXT_PRIV_CONFIG_REGS_BASE) >> PAGE_SHIFT)
366
367 /* offsets from pub/priv config space */
368 #define TXTCR_HEAP_BASE             0x0300
369 #define TXTCR_HEAP_SIZE             0x0308
370
371 #define SHA1_SIZE      20
372
373 struct sha1_hash {
374         u8 hash[SHA1_SIZE];
375 };
376
377 struct sinit_mle_data {
378         u32               version;             /* currently 6 */
379         struct sha1_hash  bios_acm_id;
380         u32               edx_senter_flags;
381         u64               mseg_valid;
382         struct sha1_hash  sinit_hash;
383         struct sha1_hash  mle_hash;
384         struct sha1_hash  stm_hash;
385         struct sha1_hash  lcp_policy_hash;
386         u32               lcp_policy_control;
387         u32               rlp_wakeup_addr;
388         u32               reserved;
389         u32               num_mdrs;
390         u32               mdrs_off;
391         u32               num_vtd_dmars;
392         u32               vtd_dmars_off;
393 } __packed;
394
395 struct acpi_table_header *tboot_get_dmar_table(struct acpi_table_header *dmar_tbl)
396 {
397         void *heap_base, *heap_ptr, *config;
398
399         if (!tboot_enabled())
400                 return dmar_tbl;
401
402         /*
403          * ACPI tables may not be DMA protected by tboot, so use DMAR copy
404          * SINIT saved in SinitMleData in TXT heap (which is DMA protected)
405          */
406
407         /* map config space in order to get heap addr */
408         config = ioremap(TXT_PUB_CONFIG_REGS_BASE, NR_TXT_CONFIG_PAGES *
409                          PAGE_SIZE);
410         if (!config)
411                 return NULL;
412
413         /* now map TXT heap */
414         heap_base = ioremap(*(u64 *)(config + TXTCR_HEAP_BASE),
415                             *(u64 *)(config + TXTCR_HEAP_SIZE));
416         iounmap(config);
417         if (!heap_base)
418                 return NULL;
419
420         /* walk heap to SinitMleData */
421         /* skip BiosData */
422         heap_ptr = heap_base + *(u64 *)heap_base;
423         /* skip OsMleData */
424         heap_ptr += *(u64 *)heap_ptr;
425         /* skip OsSinitData */
426         heap_ptr += *(u64 *)heap_ptr;
427         /* now points to SinitMleDataSize; set to SinitMleData */
428         heap_ptr += sizeof(u64);
429         /* get addr of DMAR table */
430         dmar_tbl = (struct acpi_table_header *)(heap_ptr +
431                    ((struct sinit_mle_data *)heap_ptr)->vtd_dmars_off -
432                    sizeof(u64));
433
434         /* don't unmap heap because dmar.c needs access to this */
435
436         return dmar_tbl;
437 }
438
439 int tboot_force_iommu(void)
440 {
441         if (!tboot_enabled())
442                 return 0;
443
444         if (no_iommu || swiotlb || dmar_disabled)
445                 pr_warning("Forcing Intel-IOMMU to enabled\n");
446
447         dmar_disabled = 0;
448 #ifdef CONFIG_SWIOTLB
449         swiotlb = 0;
450 #endif
451         no_iommu = 0;
452
453         return 1;
454 }