1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _ASM_X86_EFI_H
3#define _ASM_X86_EFI_H
4
5#include <asm/fpu/api.h>
6#include <asm/processor-flags.h>
7#include <asm/tlb.h>
8#include <asm/nospec-branch.h>
9#include <asm/mmu_context.h>
10#include <asm/ibt.h>
11#include <linux/build_bug.h>
12#include <linux/kernel.h>
13#include <linux/pgtable.h>
14
15extern unsigned long efi_fw_vendor, efi_config_table;
16extern unsigned long efi_mixed_mode_stack_pa;
17
18/*
19 * We map the EFI regions needed for runtime services non-contiguously,
20 * with preserved alignment on virtual addresses starting from -4G down
21 * for a total max space of 64G. This way, we provide for stable runtime
22 * services addresses across kernels so that a kexec'd kernel can still
23 * use them.
24 *
25 * This is the main reason why we're doing stable VA mappings for RT
26 * services.
27 */
28
29#define EFI32_LOADER_SIGNATURE "EL32"
30#define EFI64_LOADER_SIGNATURE "EL64"
31
32#define ARCH_EFI_IRQ_FLAGS_MASK X86_EFLAGS_IF
33
34#define EFI_UNACCEPTED_UNIT_SIZE PMD_SIZE
35
36/*
37 * The EFI services are called through variadic functions in many cases. These
38 * functions are implemented in assembler and support only a fixed number of
39 * arguments. The macros below allows us to check at build time that we don't
40 * try to call them with too many arguments.
41 *
42 * __efi_nargs() will return the number of arguments if it is 7 or less, and
43 * cause a BUILD_BUG otherwise. The limitations of the C preprocessor make it
44 * impossible to calculate the exact number of arguments beyond some
45 * pre-defined limit. The maximum number of arguments currently supported by
46 * any of the thunks is 7, so this is good enough for now and can be extended
47 * in the obvious way if we ever need more.
48 */
49
50#define __efi_nargs(...) __efi_nargs_(__VA_ARGS__)
51#define __efi_nargs_(...) __efi_nargs__(0, ##__VA_ARGS__, \
52 __efi_arg_sentinel(9), __efi_arg_sentinel(8), \
53 __efi_arg_sentinel(7), __efi_arg_sentinel(6), \
54 __efi_arg_sentinel(5), __efi_arg_sentinel(4), \
55 __efi_arg_sentinel(3), __efi_arg_sentinel(2), \
56 __efi_arg_sentinel(1), __efi_arg_sentinel(0))
57#define __efi_nargs__(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, n, ...) \
58 __take_second_arg(n, \
59 ({ BUILD_BUG_ON_MSG(1, "__efi_nargs limit exceeded"); 10; }))
60#define __efi_arg_sentinel(n) , n
61
62/*
63 * __efi_nargs_check(f, n, ...) will cause a BUILD_BUG if the ellipsis
64 * represents more than n arguments.
65 */
66
67#define __efi_nargs_check(f, n, ...) \
68 __efi_nargs_check_(f, __efi_nargs(__VA_ARGS__), n)
69#define __efi_nargs_check_(f, p, n) __efi_nargs_check__(f, p, n)
70#define __efi_nargs_check__(f, p, n) ({ \
71 BUILD_BUG_ON_MSG( \
72 (p) > (n), \
73 #f " called with too many arguments (" #p ">" #n ")"); \
74})
75
76static inline void efi_fpu_begin(void)
77{
78 /*
79 * The UEFI calling convention (UEFI spec 2.3.2 and 2.3.4) requires
80 * that FCW and MXCSR (64-bit) must be initialized prior to calling
81 * UEFI code. (Oddly the spec does not require that the FPU stack
82 * be empty.)
83 */
84 kernel_fpu_begin_mask(KFPU_387 | KFPU_MXCSR);
85}
86
87static inline void efi_fpu_end(void)
88{
89 kernel_fpu_end();
90}
91
92#ifdef CONFIG_X86_32
93#define EFI_X86_KERNEL_ALLOC_LIMIT (SZ_512M - 1)
94#else /* !CONFIG_X86_32 */
95#define EFI_X86_KERNEL_ALLOC_LIMIT EFI_ALLOC_LIMIT
96
97extern asmlinkage u64 __efi_call(void *fp, ...);
98
99extern bool efi_disable_ibt_for_runtime;
100
101#define efi_call(...) ({ \
102 __efi_nargs_check(efi_call, 7, __VA_ARGS__); \
103 __efi_call(__VA_ARGS__); \
104})
105
106#undef arch_efi_call_virt
107#define arch_efi_call_virt(p, f, args...) ({ \
108 u64 ret, ibt = ibt_save(efi_disable_ibt_for_runtime); \
109 ret = efi_call((void *)p->f, args); \
110 ibt_restore(ibt); \
111 ret; \
112})
113
114#ifdef CONFIG_KASAN
115/*
116 * CONFIG_KASAN may redefine memset to __memset. __memset function is present
117 * only in kernel binary. Since the EFI stub linked into a separate binary it
118 * doesn't have __memset(). So we should use standard memset from
119 * arch/x86/boot/compressed/string.c. The same applies to memcpy and memmove.
120 */
121#undef memcpy
122#undef memset
123#undef memmove
124#endif
125
126#endif /* CONFIG_X86_32 */
127
128extern int __init efi_memblock_x86_reserve_range(void);
129extern void __init efi_print_memmap(void);
130extern void __init efi_map_region(efi_memory_desc_t *md);
131extern void __init efi_map_region_fixed(efi_memory_desc_t *md);
132extern void efi_sync_low_kernel_mappings(void);
133extern int __init efi_alloc_page_tables(void);
134extern int __init efi_setup_page_tables(unsigned long pa_memmap, unsigned num_pages);
135extern void __init efi_runtime_update_mappings(void);
136extern void __init efi_dump_pagetable(void);
137extern void __init efi_apply_memmap_quirks(void);
138extern int __init efi_reuse_config(u64 tables, int nr_tables);
139extern void efi_delete_dummy_variable(void);
140extern void efi_crash_gracefully_on_page_fault(unsigned long phys_addr);
141extern void efi_free_boot_services(void);
142
143void arch_efi_call_virt_setup(void);
144void arch_efi_call_virt_teardown(void);
145
146extern u64 efi_setup;
147
148#ifdef CONFIG_EFI
149extern u64 __efi64_thunk(u32, ...);
150
151#define efi64_thunk(...) ({ \
152 u64 __pad[3]; /* must have space for 3 args on the stack */ \
153 __efi_nargs_check(efi64_thunk, 9, __VA_ARGS__); \
154 __efi64_thunk(__VA_ARGS__, __pad); \
155})
156
157static inline bool efi_is_mixed(void)
158{
159 if (!IS_ENABLED(CONFIG_EFI_MIXED))
160 return false;
161 return IS_ENABLED(CONFIG_X86_64) && !efi_enabled(EFI_64BIT);
162}
163
164static inline bool efi_runtime_supported(void)
165{
166 if (IS_ENABLED(CONFIG_X86_64) == efi_enabled(EFI_64BIT))
167 return true;
168
169 return IS_ENABLED(CONFIG_EFI_MIXED);
170}
171
172extern void parse_efi_setup(u64 phys_addr, u32 data_len);
173
174extern void efi_thunk_runtime_setup(void);
175efi_status_t efi_set_virtual_address_map(unsigned long memory_map_size,
176 unsigned long descriptor_size,
177 u32 descriptor_version,
178 efi_memory_desc_t *virtual_map,
179 unsigned long systab_phys);
180
181/* arch specific definitions used by the stub code */
182
183#ifdef CONFIG_EFI_MIXED
184
185#define EFI_ALLOC_LIMIT (efi_is_64bit() ? ULONG_MAX : U32_MAX)
186
187#define ARCH_HAS_EFISTUB_WRAPPERS
188
189static inline bool efi_is_64bit(void)
190{
191 extern const bool efi_is64;
192
193 return efi_is64;
194}
195
196static inline bool efi_is_native(void)
197{
198 return efi_is_64bit();
199}
200
201#define efi_table_attr(inst, attr) \
202 (efi_is_native() ? (inst)->attr \
203 : efi_mixed_table_attr((inst), attr))
204
205#define efi_mixed_table_attr(inst, attr) \
206 (__typeof__(inst->attr)) \
207 _Generic(inst->mixed_mode.attr, \
208 u32: (unsigned long)(inst->mixed_mode.attr), \
209 default: (inst->mixed_mode.attr))
210
211/*
212 * The following macros allow translating arguments if necessary from native to
213 * mixed mode. The use case for this is to initialize the upper 32 bits of
214 * output parameters, and where the 32-bit method requires a 64-bit argument,
215 * which must be split up into two arguments to be thunked properly.
216 *
217 * As examples, the AllocatePool boot service returns the address of the
218 * allocation, but it will not set the high 32 bits of the address. To ensure
219 * that the full 64-bit address is initialized, we zero-init the address before
220 * calling the thunk.
221 *
222 * The FreePages boot service takes a 64-bit physical address even in 32-bit
223 * mode. For the thunk to work correctly, a native 64-bit call of
224 * free_pages(addr, size)
225 * must be translated to
226 * efi64_thunk(free_pages, addr & U32_MAX, addr >> 32, size)
227 * so that the two 32-bit halves of addr get pushed onto the stack separately.
228 */
229
230static inline void *efi64_zero_upper(void *p)
231{
232 if (p)
233 ((u32 *)p)[1] = 0;
234 return p;
235}
236
237static inline u32 efi64_convert_status(efi_status_t status)
238{
239 return (u32)(status | (u64)status >> 32);
240}
241
242#define __efi64_split(val) (val) & U32_MAX, (u64)(val) >> 32
243
244#define __efi64_argmap_free_pages(addr, size) \
245 ((addr), 0, (size))
246
247#define __efi64_argmap_get_memory_map(mm_size, mm, key, size, ver) \
248 ((mm_size), (mm), efi64_zero_upper(key), efi64_zero_upper(size), (ver))
249
250#define __efi64_argmap_allocate_pool(type, size, buffer) \
251 ((type), (size), efi64_zero_upper(buffer))
252
253#define __efi64_argmap_locate_handle_buffer(type, proto, key, num, buf) \
254 ((type), (proto), (key), efi64_zero_upper(num), efi64_zero_upper(buf))
255
256#define __efi64_argmap_create_event(type, tpl, f, c, event) \
257 ((type), (tpl), (f), (c), efi64_zero_upper(event))
258
259#define __efi64_argmap_set_timer(event, type, time) \
260 ((event), (type), lower_32_bits(time), upper_32_bits(time))
261
262#define __efi64_argmap_wait_for_event(num, event, index) \
263 ((num), (event), efi64_zero_upper(index))
264
265#define __efi64_argmap_handle_protocol(handle, protocol, interface) \
266 ((handle), (protocol), efi64_zero_upper(interface))
267
268#define __efi64_argmap_locate_protocol(protocol, reg, interface) \
269 ((protocol), (reg), efi64_zero_upper(interface))
270
271#define __efi64_argmap_locate_device_path(protocol, path, handle) \
272 ((protocol), (path), efi64_zero_upper(handle))
273
274#define __efi64_argmap_exit(handle, status, size, data) \
275 ((handle), efi64_convert_status(status), (size), (data))
276
277/* PCI I/O */
278#define __efi64_argmap_get_location(protocol, seg, bus, dev, func) \
279 ((protocol), efi64_zero_upper(seg), efi64_zero_upper(bus), \
280 efi64_zero_upper(dev), efi64_zero_upper(func))
281
282/* LoadFile */
283#define __efi64_argmap_load_file(protocol, path, policy, bufsize, buf) \
284 ((protocol), (path), (policy), efi64_zero_upper(bufsize), (buf))
285
286/* Graphics Output Protocol */
287#define __efi64_argmap_query_mode(gop, mode, size, info) \
288 ((gop), (mode), efi64_zero_upper(size), efi64_zero_upper(info))
289
290/* TCG2 protocol */
291#define __efi64_argmap_hash_log_extend_event(prot, fl, addr, size, ev) \
292 ((prot), (fl), 0ULL, (u64)(addr), 0ULL, (u64)(size), 0ULL, ev)
293
294/* DXE services */
295#define __efi64_argmap_get_memory_space_descriptor(phys, desc) \
296 (__efi64_split(phys), (desc))
297
298#define __efi64_argmap_set_memory_space_attributes(phys, size, flags) \
299 (__efi64_split(phys), __efi64_split(size), __efi64_split(flags))
300
301/* file protocol */
302#define __efi64_argmap_open(prot, newh, fname, mode, attr) \
303 ((prot), efi64_zero_upper(newh), (fname), __efi64_split(mode), \
304 __efi64_split(attr))
305
306#define __efi64_argmap_set_position(pos) (__efi64_split(pos))
307
308/* file system protocol */
309#define __efi64_argmap_open_volume(prot, file) \
310 ((prot), efi64_zero_upper(file))
311
312/* Memory Attribute Protocol */
313#define __efi64_argmap_get_memory_attributes(protocol, phys, size, flags) \
314 ((protocol), __efi64_split(phys), __efi64_split(size), (flags))
315
316#define __efi64_argmap_set_memory_attributes(protocol, phys, size, flags) \
317 ((protocol), __efi64_split(phys), __efi64_split(size), __efi64_split(flags))
318
319#define __efi64_argmap_clear_memory_attributes(protocol, phys, size, flags) \
320 ((protocol), __efi64_split(phys), __efi64_split(size), __efi64_split(flags))
321
322/* EFI SMBIOS protocol */
323#define __efi64_argmap_get_next(protocol, smbioshandle, type, record, phandle) \
324 ((protocol), (smbioshandle), (type), efi64_zero_upper(record), \
325 efi64_zero_upper(phandle))
326/*
327 * The macros below handle the plumbing for the argument mapping. To add a
328 * mapping for a specific EFI method, simply define a macro
329 * __efi64_argmap_<method name>, following the examples above.
330 */
331
332#define __efi64_thunk_map(inst, func, ...) \
333 efi64_thunk(inst->mixed_mode.func, \
334 __efi64_argmap(__efi64_argmap_ ## func(__VA_ARGS__), \
335 (__VA_ARGS__)))
336
337#define __efi64_argmap(mapped, args) \
338 __PASTE(__efi64_argmap__, __efi_nargs(__efi_eat mapped))(mapped, args)
339#define __efi64_argmap__0(mapped, args) __efi_eval mapped
340#define __efi64_argmap__1(mapped, args) __efi_eval args
341
342#define __efi_eat(...)
343#define __efi_eval(...) __VA_ARGS__
344
345static inline efi_status_t __efi64_widen_efi_status(u64 status)
346{
347 /* use rotate to move the value of bit #31 into position #63 */
348 return ror64(word: rol32(word: status, shift: 1), shift: 1);
349}
350
351/* The macro below handles dispatching via the thunk if needed */
352
353#define efi_fn_call(inst, func, ...) \
354 (efi_is_native() ? (inst)->func(__VA_ARGS__) \
355 : efi_mixed_call((inst), func, ##__VA_ARGS__))
356
357#define efi_mixed_call(inst, func, ...) \
358 _Generic(inst->func(__VA_ARGS__), \
359 efi_status_t: \
360 __efi64_widen_efi_status( \
361 __efi64_thunk_map(inst, func, ##__VA_ARGS__)), \
362 u64: ({ BUILD_BUG(); ULONG_MAX; }), \
363 default: \
364 (__typeof__(inst->func(__VA_ARGS__))) \
365 __efi64_thunk_map(inst, func, ##__VA_ARGS__))
366
367#else /* CONFIG_EFI_MIXED */
368
369static inline bool efi_is_64bit(void)
370{
371 return IS_ENABLED(CONFIG_X86_64);
372}
373
374#endif /* CONFIG_EFI_MIXED */
375
376extern bool efi_reboot_required(void);
377extern bool efi_is_table_address(unsigned long phys_addr);
378
379extern void efi_reserve_boot_services(void);
380#else
381static inline void parse_efi_setup(u64 phys_addr, u32 data_len) {}
382static inline bool efi_reboot_required(void)
383{
384 return false;
385}
386static inline bool efi_is_table_address(unsigned long phys_addr)
387{
388 return false;
389}
390static inline void efi_reserve_boot_services(void)
391{
392}
393#endif /* CONFIG_EFI */
394
395extern int __init efi_memmap_alloc(unsigned int num_entries,
396 struct efi_memory_map_data *data);
397
398extern int __init efi_memmap_install(struct efi_memory_map_data *data);
399extern int __init efi_memmap_split_count(efi_memory_desc_t *md,
400 struct range *range);
401extern void __init efi_memmap_insert(struct efi_memory_map *old_memmap,
402 void *buf, struct efi_mem_range *mem);
403
404extern enum efi_secureboot_mode __x86_ima_efi_boot_mode(void);
405
406#define arch_ima_efi_boot_mode __x86_ima_efi_boot_mode()
407
408#ifdef CONFIG_EFI_RUNTIME_MAP
409int efi_get_runtime_map_size(void);
410int efi_get_runtime_map_desc_size(void);
411int efi_runtime_map_copy(void *buf, size_t bufsz);
412#else
413static inline int efi_get_runtime_map_size(void)
414{
415 return 0;
416}
417
418static inline int efi_get_runtime_map_desc_size(void)
419{
420 return 0;
421}
422
423static inline int efi_runtime_map_copy(void *buf, size_t bufsz)
424{
425 return 0;
426}
427
428#endif
429
430#endif /* _ASM_X86_EFI_H */
431