xref: /aosp_15_r20/external/gsc-utils/include/common.h (revision 4f2df630800bdcf1d4f0decf95d8a1cb87344f5f)
1 /* Copyright 2013 The ChromiumOS Authors
2  * Use of this source code is governed by a BSD-style license that can be
3  * found in the LICENSE file.
4  */
5 
6 /* common.h - Common includes for Chrome EC */
7 
8 #ifndef __CROS_EC_COMMON_H
9 #define __CROS_EC_COMMON_H
10 
11 #include <stdbool.h>
12 #include <stddef.h>
13 #include <stdint.h>
14 #include <inttypes.h>
15 #include "compile_time_macros.h"
16 
17 /*
18  * Macros to concatenate 2 - 4 tokens together to form a single token.
19  * Multiple levels of nesting are required to convince the preprocessor to
20  * expand currently-defined tokens before concatenation.
21  *
22  * For example, if you have
23  *     #define FOO 1
24  *     #define BAR1 42
25  * Then
26  *     #define BAZ CONCAT2(BAR, FOO)
27  * Will evaluate to BAR1, which then evaluates to 42.
28  */
29 #define CONCAT_STAGE_1(w, x, y, z) w ## x ## y ## z
30 #define CONCAT2(w, x) CONCAT_STAGE_1(w, x, , )
31 #define CONCAT3(w, x, y) CONCAT_STAGE_1(w, x, y, )
32 #define CONCAT4(w, x, y, z) CONCAT_STAGE_1(w, x, y, z)
33 
34 /*
35  * Macros to turn the argument into a string constant.
36  *
37  * Compared to directly using the preprocessor # operator, this 2-stage macro
38  * is safe with regards to using nested macros and defined arguments.
39  */
40 #define STRINGIFY0(name)  #name
41 #define STRINGIFY(name)  STRINGIFY0(name)
42 
43 /* Macros to access registers */
44 #define REG32_ADDR(addr) ((volatile uint32_t *)(addr))
45 #define REG16_ADDR(addr) ((volatile uint16_t *)(addr))
46 #define REG8_ADDR(addr)  ((volatile uint8_t  *)(addr))
47 
48 #define REG32(addr) (*REG32_ADDR(addr))
49 #define REG16(addr) (*REG16_ADDR(addr))
50 #define REG8(addr)  (*REG8_ADDR(addr))
51 
52 /*
53  * Define __aligned(n) and __packed if someone hasn't beat us to it.  Linux
54  * kernel style checking prefers these over __attribute__((packed)) and
55  * __attribute__((aligned(n))).
56  */
57 #ifndef __aligned
58 #define __aligned(n) __attribute__((aligned(n)))
59 #endif
60 
61 #ifndef __packed
62 #define __packed __attribute__((packed))
63 #endif
64 
65 /*
66  * Define __unused in the same manner.
67  */
68 #ifndef __unused
69 #define __unused __attribute__((unused))
70 #endif
71 
72 /*
73  * __maybe_unused is equivalent to the Linux kernel definition, so we
74  * can follow the Kernel style guide more closely.
75  *
76  * An example use case is a function which is only used under certain
77  * CONFIG options.
78  */
79 #ifndef __maybe_unused
80 #define __maybe_unused __attribute__((unused))
81 #endif
82 
83 /*
84  * externally_visible is required by GCC to avoid kicking out memset.
85  */
86 #ifndef __visible
87 #ifndef __clang__
88 #define __visible __attribute__((externally_visible))
89 #else
90 #define __visible __attribute__((used))
91 #endif
92 #endif
93 
94 /*
95  * Force the toolchain to keep a symbol even with Link Time Optimization
96  * activated.
97  *
98  * Useful for C functions called only from assembly or through special sections.
99  */
100 #ifndef __keep
101 #define __keep __attribute__((used)) __visible
102 #endif
103 
104 /*
105  * Place the object in the .bss.slow region.
106  *
107  * On boards with unoptimized RAM there is no penalty and it simply is appended
108  * to the .bss section.
109  */
110 #ifndef __bss_slow
111 #define __bss_slow __attribute__((section(".bss.slow")))
112 #endif
113 
114 /* gcc does not support __has_feature */
115 #ifndef __has_feature
116 #define __has_feature(x) 0
117 #endif
118 
119 /*
120  * Use this to prevent AddressSanitizer from putting guards around some global
121  * variables (e.g. hook/commands "arrays" that are put together at link time).
122  */
123 #ifndef __no_sanitize_address
124 #if __has_feature(address_sanitizer)
125 #define __no_sanitize_address __attribute__((no_sanitize("address")))
126 #else
127 #define __no_sanitize_address
128 #endif
129 #endif
130 
131 #ifndef __warn_unused_result
132 #define __warn_unused_result __attribute__((warn_unused_result))
133 #endif
134 
135 #ifdef TEST_PINWEAVER_FUZZ
136 /**
137  *  Workaround: Clang incorrectly handles profiling information
138  *  used for fuzzing with __attribute__((always_inline)).
139  */
140 #undef __always_inline
141 #define __always_inline static inline
142 #else
143 #ifndef __always_inline
144 #define __always_inline __inline __attribute__((always_inline))
145 #endif
146 #endif
147 
148 /*
149  * Macros for combining bytes into larger integers. _LE and _BE signify little
150  * and big endian versions respectively.
151  */
152 #define UINT16_FROM_BYTES(lsb, msb) ((lsb) | (msb) << 8)
153 #define UINT16_FROM_BYTE_ARRAY_LE(data, lsb_index) \
154 	UINT16_FROM_BYTES((data)[(lsb_index)], (data)[(lsb_index) + 1])
155 #define UINT16_FROM_BYTE_ARRAY_BE(data, msb_index) \
156 	UINT16_FROM_BYTES((data)[(msb_index) + 1], (data)[(msb_index)])
157 
158 #define UINT32_FROM_BYTES(lsb, byte1, byte2, msb) \
159 	((lsb) | (byte1) << 8 | (byte2) << 16 | (msb) << 24)
160 #define UINT32_FROM_BYTE_ARRAY_LE(data, lsb_index) \
161 	UINT32_FROM_BYTES((data)[(lsb_index)], (data)[(lsb_index) + 1], \
162 			  (data)[(lsb_index) + 2], (data)[(lsb_index) + 3])
163 #define UINT32_FROM_BYTE_ARRAY_BE(data, msb_index) \
164 	UINT32_FROM_BYTES((data)[(msb_index) + 3], (data)[(msb_index) + 2], \
165 			  (data)[(msb_index) + 1], (data)[(msb_index)])
166 
167 /* There isn't really a better place for this */
168 #define C_TO_K(temp_c) ((temp_c) + 273)
169 #define K_TO_C(temp_c) ((temp_c) - 273)
170 #define CELSIUS_TO_DECI_KELVIN(temp_c) ((temp_c) * 10 + 2731)
171 #define DECI_KELVIN_TO_CELSIUS(temp_dk) ((temp_dk - 2731) / 10)
172 
173 /* Calculate a value with error margin considered. For example,
174  * TARGET_WITH_MARGIN(X, 5) returns X' where X' * 100.5% is almost equal to
175  * but does not exceed X. */
176 #define TARGET_WITH_MARGIN(target, tenths_percent) \
177 	(((target) * 1000) / (1000 + (tenths_percent)))
178 
179 /* Include top-level configuration file */
180 #include "config.h"
181 
182 /* Canonical list of module IDs */
183 #include "module_id.h"
184 
185 /* List of common error codes that can be returned */
186 enum ec_error_list {
187 	/* Success - no error */
188 	EC_SUCCESS = 0,
189 	/* Unknown error */
190 	EC_ERROR_UNKNOWN = 1,
191 	/* Function not implemented yet */
192 	EC_ERROR_UNIMPLEMENTED = 2,
193 	/* Overflow error; too much input provided. */
194 	EC_ERROR_OVERFLOW = 3,
195 	/* Timeout */
196 	EC_ERROR_TIMEOUT = 4,
197 	/* Invalid argument */
198 	EC_ERROR_INVAL = 5,
199 	/* Already in use, or not ready yet */
200 	EC_ERROR_BUSY = 6,
201 	/* Access denied */
202 	EC_ERROR_ACCESS_DENIED = 7,
203 	/* Failed because component does not have power */
204 	EC_ERROR_NOT_POWERED = 8,
205 	/* Failed because component is not calibrated */
206 	EC_ERROR_NOT_CALIBRATED = 9,
207 	/* Failed because CRC error */
208 	EC_ERROR_CRC = 10,
209 	/* Invalid console command param (PARAMn means parameter n is bad) */
210 	EC_ERROR_PARAM1 = 11,
211 	EC_ERROR_PARAM2 = 12,
212 	EC_ERROR_PARAM3 = 13,
213 	EC_ERROR_PARAM4 = 14,
214 	EC_ERROR_PARAM5 = 15,
215 	EC_ERROR_PARAM6 = 16,
216 	EC_ERROR_PARAM7 = 17,
217 	EC_ERROR_PARAM8 = 18,
218 	EC_ERROR_PARAM9 = 19,
219 	/* Wrong number of params */
220 	EC_ERROR_PARAM_COUNT = 20,
221 	/* Interrupt event not handled */
222 	EC_ERROR_NOT_HANDLED = 21,
223 	/* Data has not changed */
224 	EC_ERROR_UNCHANGED = 22,
225 	/* Memory allocation */
226 	EC_ERROR_MEMORY_ALLOCATION = 23,
227 	/* Invalid to configure in the current module mode/stage */
228 	EC_ERROR_INVALID_CONFIG = 24,
229 	/* something wrong in a HW */
230 	EC_ERROR_HW_INTERNAL = 25,
231 
232 	/* Sometimes operation is expected to have to be repeated. */
233 	EC_ERROR_TRY_AGAIN = 26,
234 
235 	/* Verified boot errors */
236 	EC_ERROR_VBOOT_SIGNATURE = 0x1000, /* 4096 */
237 	EC_ERROR_VBOOT_SIG_MAGIC = 0x1001,
238 	EC_ERROR_VBOOT_SIG_SIZE = 0x1002,
239 	EC_ERROR_VBOOT_SIG_ALGORITHM = 0x1003,
240 	EC_ERROR_VBOOT_HASH_ALGORITHM = 0x1004,
241 	EC_ERROR_VBOOT_SIG_OFFSET = 0x1005,
242 	EC_ERROR_VBOOT_DATA_SIZE = 0x1006,
243 
244 	/* Verified boot key errors */
245 	EC_ERROR_VBOOT_KEY = 0x1100,
246 	EC_ERROR_VBOOT_KEY_MAGIC = 0x1101,
247 	EC_ERROR_VBOOT_KEY_SIZE = 0x1102,
248 
249 	/* Verified boot data errors */
250 	EC_ERROR_VBOOT_DATA = 0x1200,
251 	EC_ERROR_VBOOT_DATA_VERIFY = 0x1201,
252 	EC_ERROR_VBOOT_DATA_INCOMPATIBLE = 0x1202,
253 	EC_ERROR_VBOOT_DATA_UNDERSIZED = 0x1203,
254 
255 	/* Module-internal error codes may use this range.   */
256 	EC_ERROR_INTERNAL_FIRST = 0x10000,
257 	EC_ERROR_INTERNAL_LAST = 0x1FFFF
258 };
259 
260 /*
261  * Define test_mockable and test_mockable_static for mocking
262  * functions.
263  */
264 #ifdef TEST_BUILD
265 #define test_mockable __attribute__((weak))
266 #define test_mockable_static __attribute__((weak))
267 #define test_export_static
268 #else
269 #define test_mockable
270 #define test_mockable_static static
271 #define test_export_static static
272 #endif
273 
274 /*
275  * Attribute to define functions to only be used in test code, causing
276  * a compiler error if used without TEST_BUILD defined.
277  *
278  * Example usage (add to prototype in header):
279  * __test_only void foo(void);
280  */
281 #ifdef TEST_BUILD
282 #define __test_only
283 #else
284 #define __test_only __error("This function should only be used by tests")
285 #endif
286 
287 /*
288  * Weak symbol markers
289  *
290  * These macros are used to annotate weak definitions, their declarations, and
291  * overriding definitions.
292  *
293  * __override_proto: declarations
294  * __override: definitions which take precedence
295  * __overridable: default (weak) definitions
296  *
297  * For example, in foo.h:
298  *   __override_proto void foo(void);
299  *
300  * and in foo.c:
301  *   __overridable void foo(void) {
302  *     ...
303  *   }
304  *
305  * and in board.c:
306  *   __override void foo(void) {
307  *     ...
308  *   }
309  */
310 #define __override_proto
311 #define __override
312 #define __overridable	__attribute__((weak))
313 
314 /*
315  * Mark functions that collide with stdlib so they can be hidden when linking
316  * against libraries that require stdlib. HIDE_EC_STDLIB should be defined
317  * before including common.h from code that links to cstdlib.
318  */
319 #ifdef TEST_FUZZ
320 #define __stdlib_compat __attribute__((visibility("hidden")))
321 #else /* TEST_FUZZ */
322 #define __stdlib_compat
323 #endif /* TEST_FUZZ */
324 
325 /*
326  * __cfg_select(CONFIG_NAME, EMPTY, OTHERWISE) is a macro used for
327  * defining other macros which conditionally select code based on a
328  * config option. It will generate the argument passed as EMPTY
329  * when CONFIG_NAME was defined to the empty string, and OTHERWISE
330  * when the argument was not defined or defined to something
331  * non-empty.
332  *
333  * Generally speaking, macros which use this should make some sort of
334  * context-dependent assertion in OTHERWISE that CONFIG_NAME is
335  * undefined, rather than defined to something else. This usually
336  * involves tricks with __builtin_strcmp.
337  */
338 #define __cfg_select(cfg, empty, otherwise)     \
339 	__cfg_select_1(cfg, empty, otherwise)
340 #define __cfg_select_placeholder_ _,
341 #define __cfg_select_1(value, empty, otherwise)			  \
342 	__cfg_select_2(__cfg_select_placeholder_##value, empty, otherwise)
343 #define __cfg_select_2(arg1_or_junk, empty, otherwise)		\
344 	__cfg_select_3(arg1_or_junk _, empty, otherwise)
345 #define __cfg_select_3(_ignore1, _ignore2, select, ...) select
346 
347 /*
348  * This version concatenates a BUILD_ASSERT(...); before OTHERWISE,
349  * handling the __builtin_strcmp trickery where a BUILD_ASSERT is
350  * appropriate in the context.
351  */
352 #define __cfg_select_build_assert(cfg, value, empty, undef)	\
353 	__cfg_select(						\
354 		value,						\
355 		empty,						\
356 		BUILD_ASSERT(					\
357 			__builtin_strcmp(cfg, #value) == 0);	\
358 		undef)
359 
360 /*
361  * Attribute for generating an error if a function is used.
362  *
363  * Clang does not have a function attribute to do this. Rely on linker
364  * errors. :(
365  */
366 #ifdef __clang__
367 #define __error(msg) __attribute__((section("/DISCARD/")))
368 #else
369 #define __error(msg) __attribute__((error(msg)))
370 #endif
371 
372 /*
373  * Getting something that works in C and CPP for an arg that may or may
374  * not be defined is tricky.
375  *
376  * Compare the option name with the value string in the OTHERWISE to
377  * __cfg_select. If they are identical we assume that the value was
378  * undefined and return 0. If the value happens to be anything else we
379  * call an undefined method that will raise a compiler error. This
380  * technique requires that the optimizer be enabled so it can remove
381  * the undefined function call.
382  */
383 #define __config_enabled(cfg, value)					      \
384 	__cfg_select(							      \
385 		value, 1, ({						      \
386 			int __undefined = __builtin_strcmp(cfg, #value) == 0; \
387 			extern int IS_ENABLED_BAD_ARGS(void) __error(	      \
388 				cfg " must be <blank>, or not defined.");     \
389 			if (!__undefined)				      \
390 				IS_ENABLED_BAD_ARGS();			      \
391 			0;						      \
392 		}))
393 
394 /**
395  * Checks if a config option is enabled or disabled
396  *
397  * Enabled examples:
398  *     #define CONFIG_FOO
399  *
400  * Disabled examples:
401  *     #undef CONFIG_FOO
402  *
403  * If the option is defined to any value a compiler error will be thrown.
404  *
405  * Note: This macro will only function inside a code block due to the way
406  * it checks for unknown values.
407  */
408 #define IS_ENABLED(option) __config_enabled(#option, option)
409 
410 /**
411  * Makes a global variable static when a config option is enabled,
412  * extern otherwise (with the intention to cause linker errors if the
413  * variable is used outside of a config context, for example thru
414  * IS_ENABLED, that it should be).
415  *
416  * This follows the same constraints as IS_ENABLED, the config option
417  * should be defined to nothing or undefined.
418  */
419 #define STATIC_IF(option)						\
420 	__cfg_select_build_assert(#option, option, static, extern)
421 
422 /**
423  * STATIC_IF_NOT is just like STATIC_IF, but makes the variable static
424  * only if the config option is *not* defined, extern if it is.
425  *
426  * This is to assert that a variable will go unused with a certain
427  * config option.
428  */
429 #define STATIC_IF_NOT(option)						\
430 	__cfg_select_build_assert(#option, option, extern, static)
431 
432 #endif  /* __CROS_EC_COMMON_H */
433