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 } 448