1 // SPDX-License-Identifier: GPL-2.0-only
3 * tboot.c: main implementation of helper functions used by kernel for
4 * runtime support of Intel(R) Trusted Execution Technology
6 * Copyright (c) 2006-2009, Intel Corporation
9 #include <linux/intel-iommu.h>
10 #include <linux/init_task.h>
11 #include <linux/spinlock.h>
12 #include <linux/export.h>
13 #include <linux/delay.h>
14 #include <linux/sched.h>
15 #include <linux/init.h>
16 #include <linux/dmar.h>
17 #include <linux/cpu.h>
18 #include <linux/pfn.h>
20 #include <linux/tboot.h>
21 #include <linux/debugfs.h>
23 #include <asm/realmode.h>
24 #include <asm/processor.h>
25 #include <asm/bootparam.h>
26 #include <asm/pgtable.h>
27 #include <asm/pgalloc.h>
28 #include <asm/swiotlb.h>
29 #include <asm/fixmap.h>
30 #include <asm/proto.h>
31 #include <asm/setup.h>
32 #include <asm/e820/api.h>
35 #include "../realmode/rm/wakeup.h"
37 /* Global pointer to shared data; NULL means no measured launch. */
38 struct tboot *tboot __read_mostly;
41 /* timeout for APs (in secs) to enter wait-for-SIPI state during shutdown */
42 #define AP_WAIT_TIMEOUT 1
45 #define pr_fmt(fmt) "tboot: " fmt
47 static u8 tboot_uuid[16] __initdata = TBOOT_UUID;
49 void __init tboot_probe(void)
51 /* Look for valid page-aligned address for shared page. */
52 if (!boot_params.tboot_addr)
55 * also verify that it is mapped as we expect it before calling
56 * set_fixmap(), to reduce chance of garbage value causing crash
58 if (!e820__mapped_any(boot_params.tboot_addr,
59 boot_params.tboot_addr, E820_TYPE_RESERVED)) {
60 pr_warn("non-0 tboot_addr but it is not of type E820_TYPE_RESERVED\n");
64 /* Map and check for tboot UUID. */
65 set_fixmap(FIX_TBOOT_BASE, boot_params.tboot_addr);
66 tboot = (struct tboot *)fix_to_virt(FIX_TBOOT_BASE);
67 if (memcmp(&tboot_uuid, &tboot->uuid, sizeof(tboot->uuid))) {
68 pr_warn("tboot at 0x%llx is invalid\n", boot_params.tboot_addr);
72 if (tboot->version < 5) {
73 pr_warn("tboot version is invalid: %u\n", tboot->version);
78 pr_info("found shared page at phys addr 0x%llx:\n",
79 boot_params.tboot_addr);
80 pr_debug("version: %d\n", tboot->version);
81 pr_debug("log_addr: 0x%08x\n", tboot->log_addr);
82 pr_debug("shutdown_entry: 0x%x\n", tboot->shutdown_entry);
83 pr_debug("tboot_base: 0x%08x\n", tboot->tboot_base);
84 pr_debug("tboot_size: 0x%x\n", tboot->tboot_size);
87 static pgd_t *tboot_pg_dir;
88 static struct mm_struct tboot_mm = {
90 .pgd = swapper_pg_dir,
91 .mm_users = ATOMIC_INIT(2),
92 .mm_count = ATOMIC_INIT(1),
93 .mmap_sem = __RWSEM_INITIALIZER(init_mm.mmap_sem),
94 .page_table_lock = __SPIN_LOCK_UNLOCKED(init_mm.page_table_lock),
95 .mmlist = LIST_HEAD_INIT(init_mm.mmlist),
98 static inline void switch_to_tboot_pt(void)
100 write_cr3(virt_to_phys(tboot_pg_dir));
103 static int map_tboot_page(unsigned long vaddr, unsigned long pfn,
112 pgd = pgd_offset(&tboot_mm, vaddr);
113 p4d = p4d_alloc(&tboot_mm, pgd, vaddr);
116 pud = pud_alloc(&tboot_mm, p4d, vaddr);
119 pmd = pmd_alloc(&tboot_mm, pud, vaddr);
122 pte = pte_alloc_map(&tboot_mm, pmd, vaddr);
125 set_pte_at(&tboot_mm, vaddr, pte, pfn_pte(pfn, prot));
129 * PTI poisons low addresses in the kernel page tables in the
130 * name of making them unusable for userspace. To execute
131 * code at such a low address, the poison must be cleared.
133 * Note: 'pgd' actually gets set in p4d_alloc() _or_
134 * pud_alloc() depending on 4/5-level paging.
136 pgd->pgd &= ~_PAGE_NX;
141 static int map_tboot_pages(unsigned long vaddr, unsigned long start_pfn,
144 /* Reuse the original kernel mapping */
145 tboot_pg_dir = pgd_alloc(&tboot_mm);
149 for (; nr > 0; nr--, vaddr += PAGE_SIZE, start_pfn++) {
150 if (map_tboot_page(vaddr, start_pfn, PAGE_KERNEL_EXEC))
157 static void tboot_create_trampoline(void)
159 u32 map_base, map_size;
161 /* Create identity map for tboot shutdown code. */
162 map_base = PFN_DOWN(tboot->tboot_base);
163 map_size = PFN_UP(tboot->tboot_size);
164 if (map_tboot_pages(map_base << PAGE_SHIFT, map_base, map_size))
165 panic("tboot: Error mapping tboot pages (mfns) @ 0x%x, 0x%x\n",
169 #ifdef CONFIG_ACPI_SLEEP
171 static void add_mac_region(phys_addr_t start, unsigned long size)
173 struct tboot_mac_region *mr;
174 phys_addr_t end = start + size;
176 if (tboot->num_mac_regions >= MAX_TB_MAC_REGIONS)
177 panic("tboot: Too many MAC regions\n");
180 mr = &tboot->mac_regions[tboot->num_mac_regions++];
181 mr->start = round_down(start, PAGE_SIZE);
182 mr->size = round_up(end, PAGE_SIZE) - mr->start;
186 static int tboot_setup_sleep(void)
190 tboot->num_mac_regions = 0;
192 for (i = 0; i < e820_table->nr_entries; i++) {
193 if ((e820_table->entries[i].type != E820_TYPE_RAM)
194 && (e820_table->entries[i].type != E820_TYPE_RESERVED_KERN))
197 add_mac_region(e820_table->entries[i].addr, e820_table->entries[i].size);
200 tboot->acpi_sinfo.kernel_s3_resume_vector =
201 real_mode_header->wakeup_start;
206 #else /* no CONFIG_ACPI_SLEEP */
208 static int tboot_setup_sleep(void)
210 /* S3 shutdown requested, but S3 not supported by the kernel... */
217 void tboot_shutdown(u32 shutdown_type)
219 void (*shutdown)(void);
221 if (!tboot_enabled())
225 * if we're being called before the 1:1 mapping is set up then just
226 * return and let the normal shutdown happen; this should only be
227 * due to very early panic()
232 /* if this is S3 then set regions to MAC */
233 if (shutdown_type == TB_SHUTDOWN_S3)
234 if (tboot_setup_sleep())
237 tboot->shutdown_type = shutdown_type;
239 switch_to_tboot_pt();
241 shutdown = (void(*)(void))(unsigned long)tboot->shutdown_entry;
244 /* should not reach here */
249 static void tboot_copy_fadt(const struct acpi_table_fadt *fadt)
251 #define TB_COPY_GAS(tbg, g) \
252 tbg.space_id = g.space_id; \
253 tbg.bit_width = g.bit_width; \
254 tbg.bit_offset = g.bit_offset; \
255 tbg.access_width = g.access_width; \
256 tbg.address = g.address;
258 TB_COPY_GAS(tboot->acpi_sinfo.pm1a_cnt_blk, fadt->xpm1a_control_block);
259 TB_COPY_GAS(tboot->acpi_sinfo.pm1b_cnt_blk, fadt->xpm1b_control_block);
260 TB_COPY_GAS(tboot->acpi_sinfo.pm1a_evt_blk, fadt->xpm1a_event_block);
261 TB_COPY_GAS(tboot->acpi_sinfo.pm1b_evt_blk, fadt->xpm1b_event_block);
264 * We need phys addr of waking vector, but can't use virt_to_phys() on
265 * &acpi_gbl_FACS because it is ioremap'ed, so calc from FACS phys
268 tboot->acpi_sinfo.wakeup_vector = fadt->facs +
269 offsetof(struct acpi_table_facs, firmware_waking_vector);
272 static int tboot_sleep(u8 sleep_state, u32 pm1a_control, u32 pm1b_control)
274 static u32 acpi_shutdown_map[ACPI_S_STATE_COUNT] = {
275 /* S0,1,2: */ -1, -1, -1,
276 /* S3: */ TB_SHUTDOWN_S3,
277 /* S4: */ TB_SHUTDOWN_S4,
278 /* S5: */ TB_SHUTDOWN_S5 };
280 if (!tboot_enabled())
283 tboot_copy_fadt(&acpi_gbl_FADT);
284 tboot->acpi_sinfo.pm1a_cnt_val = pm1a_control;
285 tboot->acpi_sinfo.pm1b_cnt_val = pm1b_control;
286 /* we always use the 32b wakeup vector */
287 tboot->acpi_sinfo.vector_width = 32;
289 if (sleep_state >= ACPI_S_STATE_COUNT ||
290 acpi_shutdown_map[sleep_state] == -1) {
291 pr_warn("unsupported sleep state 0x%x\n", sleep_state);
295 tboot_shutdown(acpi_shutdown_map[sleep_state]);
299 static int tboot_extended_sleep(u8 sleep_state, u32 val_a, u32 val_b)
301 if (!tboot_enabled())
304 pr_warn("tboot is not able to suspend on platforms with reduced hardware sleep (ACPIv5)");
308 static atomic_t ap_wfs_count;
310 static int tboot_wait_for_aps(int num_aps)
312 unsigned long timeout;
314 timeout = AP_WAIT_TIMEOUT*HZ;
315 while (atomic_read((atomic_t *)&tboot->num_in_wfs) != num_aps &&
322 pr_warn("tboot wait for APs timeout\n");
324 return !(atomic_read((atomic_t *)&tboot->num_in_wfs) == num_aps);
327 static int tboot_dying_cpu(unsigned int cpu)
329 atomic_inc(&ap_wfs_count);
330 if (num_online_cpus() == 1) {
331 if (tboot_wait_for_aps(atomic_read(&ap_wfs_count)))
337 #ifdef CONFIG_DEBUG_FS
339 #define TBOOT_LOG_UUID { 0x26, 0x25, 0x19, 0xc0, 0x30, 0x6b, 0xb4, 0x4d, \
340 0x4c, 0x84, 0xa3, 0xe9, 0x53, 0xb8, 0x81, 0x74 }
342 #define TBOOT_SERIAL_LOG_ADDR 0x60000
343 #define TBOOT_SERIAL_LOG_SIZE 0x08000
344 #define LOG_MAX_SIZE_OFF 16
345 #define LOG_BUF_OFF 24
347 static uint8_t tboot_log_uuid[16] = TBOOT_LOG_UUID;
349 static ssize_t tboot_log_read(struct file *file, char __user *user_buf, size_t count, loff_t *ppos)
351 void __iomem *log_base;
357 log_base = ioremap_nocache(TBOOT_SERIAL_LOG_ADDR, TBOOT_SERIAL_LOG_SIZE);
361 memcpy_fromio(log_uuid, log_base, sizeof(log_uuid));
362 if (memcmp(&tboot_log_uuid, log_uuid, sizeof(log_uuid)))
365 max_size = readl(log_base + LOG_MAX_SIZE_OFF);
366 if (*ppos >= max_size) {
371 if (*ppos + count > max_size)
372 count = max_size - *ppos;
374 kbuf = kmalloc(count, GFP_KERNEL);
380 memcpy_fromio(kbuf, log_base + LOG_BUF_OFF + *ppos, count);
381 if (copy_to_user(user_buf, kbuf, count))
397 static const struct file_operations tboot_log_fops = {
398 .read = tboot_log_read,
399 .llseek = default_llseek,
402 #endif /* CONFIG_DEBUG_FS */
404 static __init int tboot_late_init(void)
406 if (!tboot_enabled())
409 tboot_create_trampoline();
411 atomic_set(&ap_wfs_count, 0);
412 cpuhp_setup_state(CPUHP_AP_X86_TBOOT_DYING, "x86/tboot:dying", NULL,
414 #ifdef CONFIG_DEBUG_FS
415 debugfs_create_file("tboot_log", S_IRUSR,
416 arch_debugfs_dir, NULL, &tboot_log_fops);
419 acpi_os_set_prepare_sleep(&tboot_sleep);
420 acpi_os_set_prepare_extended_sleep(&tboot_extended_sleep);
424 late_initcall(tboot_late_init);
427 * TXT configuration registers (offsets from TXT_{PUB, PRIV}_CONFIG_REGS_BASE)
430 #define TXT_PUB_CONFIG_REGS_BASE 0xfed30000
431 #define TXT_PRIV_CONFIG_REGS_BASE 0xfed20000
433 /* # pages for each config regs space - used by fixmap */
434 #define NR_TXT_CONFIG_PAGES ((TXT_PUB_CONFIG_REGS_BASE - \
435 TXT_PRIV_CONFIG_REGS_BASE) >> PAGE_SHIFT)
437 /* offsets from pub/priv config space */
438 #define TXTCR_HEAP_BASE 0x0300
439 #define TXTCR_HEAP_SIZE 0x0308
447 struct sinit_mle_data {
448 u32 version; /* currently 6 */
449 struct sha1_hash bios_acm_id;
450 u32 edx_senter_flags;
452 struct sha1_hash sinit_hash;
453 struct sha1_hash mle_hash;
454 struct sha1_hash stm_hash;
455 struct sha1_hash lcp_policy_hash;
456 u32 lcp_policy_control;
465 struct acpi_table_header *tboot_get_dmar_table(struct acpi_table_header *dmar_tbl)
467 void *heap_base, *heap_ptr, *config;
469 if (!tboot_enabled())
473 * ACPI tables may not be DMA protected by tboot, so use DMAR copy
474 * SINIT saved in SinitMleData in TXT heap (which is DMA protected)
477 /* map config space in order to get heap addr */
478 config = ioremap(TXT_PUB_CONFIG_REGS_BASE, NR_TXT_CONFIG_PAGES *
483 /* now map TXT heap */
484 heap_base = ioremap(*(u64 *)(config + TXTCR_HEAP_BASE),
485 *(u64 *)(config + TXTCR_HEAP_SIZE));
490 /* walk heap to SinitMleData */
492 heap_ptr = heap_base + *(u64 *)heap_base;
494 heap_ptr += *(u64 *)heap_ptr;
495 /* skip OsSinitData */
496 heap_ptr += *(u64 *)heap_ptr;
497 /* now points to SinitMleDataSize; set to SinitMleData */
498 heap_ptr += sizeof(u64);
499 /* get addr of DMAR table */
500 dmar_tbl = (struct acpi_table_header *)(heap_ptr +
501 ((struct sinit_mle_data *)heap_ptr)->vtd_dmars_off -
504 /* don't unmap heap because dmar.c needs access to this */
509 int tboot_force_iommu(void)
511 if (!tboot_enabled())
514 if (intel_iommu_tboot_noforce)
517 if (no_iommu || swiotlb || dmar_disabled)
518 pr_warn("Forcing Intel-IOMMU to enabled\n");
521 #ifdef CONFIG_SWIOTLB