xref: /linux-6.15/include/linux/arm-smccc.h (revision 42e4eefb)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (c) 2015, Linaro Limited
4  */
5 #ifndef __LINUX_ARM_SMCCC_H
6 #define __LINUX_ARM_SMCCC_H
7 
8 #include <linux/init.h>
9 #include <uapi/linux/const.h>
10 
11 /*
12  * This file provides common defines for ARM SMC Calling Convention as
13  * specified in
14  * https://developer.arm.com/docs/den0028/latest
15  *
16  * This code is up-to-date with version DEN 0028 C
17  */
18 
19 #define ARM_SMCCC_STD_CALL	        _AC(0,U)
20 #define ARM_SMCCC_FAST_CALL	        _AC(1,U)
21 #define ARM_SMCCC_TYPE_SHIFT		31
22 
23 #define ARM_SMCCC_SMC_32		0
24 #define ARM_SMCCC_SMC_64		1
25 #define ARM_SMCCC_CALL_CONV_SHIFT	30
26 
27 #define ARM_SMCCC_OWNER_MASK		0x3F
28 #define ARM_SMCCC_OWNER_SHIFT		24
29 
30 #define ARM_SMCCC_FUNC_MASK		0xFFFF
31 
32 #define ARM_SMCCC_IS_FAST_CALL(smc_val)	\
33 	((smc_val) & (ARM_SMCCC_FAST_CALL << ARM_SMCCC_TYPE_SHIFT))
34 #define ARM_SMCCC_IS_64(smc_val) \
35 	((smc_val) & (ARM_SMCCC_SMC_64 << ARM_SMCCC_CALL_CONV_SHIFT))
36 #define ARM_SMCCC_FUNC_NUM(smc_val)	((smc_val) & ARM_SMCCC_FUNC_MASK)
37 #define ARM_SMCCC_OWNER_NUM(smc_val) \
38 	(((smc_val) >> ARM_SMCCC_OWNER_SHIFT) & ARM_SMCCC_OWNER_MASK)
39 
40 #define ARM_SMCCC_CALL_VAL(type, calling_convention, owner, func_num) \
41 	(((type) << ARM_SMCCC_TYPE_SHIFT) | \
42 	((calling_convention) << ARM_SMCCC_CALL_CONV_SHIFT) | \
43 	(((owner) & ARM_SMCCC_OWNER_MASK) << ARM_SMCCC_OWNER_SHIFT) | \
44 	((func_num) & ARM_SMCCC_FUNC_MASK))
45 
46 #define ARM_SMCCC_OWNER_ARCH		0
47 #define ARM_SMCCC_OWNER_CPU		1
48 #define ARM_SMCCC_OWNER_SIP		2
49 #define ARM_SMCCC_OWNER_OEM		3
50 #define ARM_SMCCC_OWNER_STANDARD	4
51 #define ARM_SMCCC_OWNER_STANDARD_HYP	5
52 #define ARM_SMCCC_OWNER_VENDOR_HYP	6
53 #define ARM_SMCCC_OWNER_TRUSTED_APP	48
54 #define ARM_SMCCC_OWNER_TRUSTED_APP_END	49
55 #define ARM_SMCCC_OWNER_TRUSTED_OS	50
56 #define ARM_SMCCC_OWNER_TRUSTED_OS_END	63
57 
58 #define ARM_SMCCC_QUIRK_NONE		0
59 #define ARM_SMCCC_QUIRK_QCOM_A6		1 /* Save/restore register a6 */
60 
61 #define ARM_SMCCC_VERSION_1_0		0x10000
62 #define ARM_SMCCC_VERSION_1_1		0x10001
63 #define ARM_SMCCC_VERSION_1_2		0x10002
64 
65 #define ARM_SMCCC_VERSION_FUNC_ID					\
66 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,				\
67 			   ARM_SMCCC_SMC_32,				\
68 			   0, 0)
69 
70 #define ARM_SMCCC_ARCH_FEATURES_FUNC_ID					\
71 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,				\
72 			   ARM_SMCCC_SMC_32,				\
73 			   0, 1)
74 
75 #define ARM_SMCCC_ARCH_SOC_ID						\
76 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,				\
77 			   ARM_SMCCC_SMC_32,				\
78 			   0, 2)
79 
80 #define ARM_SMCCC_ARCH_WORKAROUND_1					\
81 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,				\
82 			   ARM_SMCCC_SMC_32,				\
83 			   0, 0x8000)
84 
85 #define ARM_SMCCC_ARCH_WORKAROUND_2					\
86 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,				\
87 			   ARM_SMCCC_SMC_32,				\
88 			   0, 0x7fff)
89 
90 #define SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED	1
91 
92 /* Paravirtualised time calls (defined by ARM DEN0057A) */
93 #define ARM_SMCCC_HV_PV_TIME_FEATURES				\
94 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,			\
95 			   ARM_SMCCC_SMC_64,			\
96 			   ARM_SMCCC_OWNER_STANDARD_HYP,	\
97 			   0x20)
98 
99 #define ARM_SMCCC_HV_PV_TIME_ST					\
100 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,			\
101 			   ARM_SMCCC_SMC_64,			\
102 			   ARM_SMCCC_OWNER_STANDARD_HYP,	\
103 			   0x21)
104 
105 /* TRNG entropy source calls (defined by ARM DEN0098) */
106 #define ARM_SMCCC_TRNG_VERSION					\
107 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,			\
108 			   ARM_SMCCC_SMC_32,			\
109 			   ARM_SMCCC_OWNER_STANDARD,		\
110 			   0x50)
111 
112 #define ARM_SMCCC_TRNG_FEATURES					\
113 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,			\
114 			   ARM_SMCCC_SMC_32,			\
115 			   ARM_SMCCC_OWNER_STANDARD,		\
116 			   0x51)
117 
118 #define ARM_SMCCC_TRNG_GET_UUID					\
119 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,			\
120 			   ARM_SMCCC_SMC_32,			\
121 			   ARM_SMCCC_OWNER_STANDARD,		\
122 			   0x52)
123 
124 #define ARM_SMCCC_TRNG_RND32					\
125 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,			\
126 			   ARM_SMCCC_SMC_32,			\
127 			   ARM_SMCCC_OWNER_STANDARD,		\
128 			   0x53)
129 
130 #define ARM_SMCCC_TRNG_RND64					\
131 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,			\
132 			   ARM_SMCCC_SMC_64,			\
133 			   ARM_SMCCC_OWNER_STANDARD,		\
134 			   0x53)
135 
136 /*
137  * Return codes defined in ARM DEN 0070A
138  * ARM DEN 0070A is now merged/consolidated into ARM DEN 0028 C
139  */
140 #define SMCCC_RET_SUCCESS			0
141 #define SMCCC_RET_NOT_SUPPORTED			-1
142 #define SMCCC_RET_NOT_REQUIRED			-2
143 #define SMCCC_RET_INVALID_PARAMETER		-3
144 
145 #ifndef __ASSEMBLY__
146 
147 #include <linux/linkage.h>
148 #include <linux/types.h>
149 
150 enum arm_smccc_conduit {
151 	SMCCC_CONDUIT_NONE,
152 	SMCCC_CONDUIT_SMC,
153 	SMCCC_CONDUIT_HVC,
154 };
155 
156 /**
157  * arm_smccc_1_1_get_conduit()
158  *
159  * Returns the conduit to be used for SMCCCv1.1 or later.
160  *
161  * When SMCCCv1.1 is not present, returns SMCCC_CONDUIT_NONE.
162  */
163 enum arm_smccc_conduit arm_smccc_1_1_get_conduit(void);
164 
165 /**
166  * arm_smccc_get_version()
167  *
168  * Returns the version to be used for SMCCCv1.1 or later.
169  *
170  * When SMCCCv1.1 or above is not present, returns SMCCCv1.0, but this
171  * does not imply the presence of firmware or a valid conduit. Caller
172  * handling SMCCCv1.0 must determine the conduit by other means.
173  */
174 u32 arm_smccc_get_version(void);
175 
176 void __init arm_smccc_version_init(u32 version, enum arm_smccc_conduit conduit);
177 
178 /**
179  * struct arm_smccc_res - Result from SMC/HVC call
180  * @a0-a3 result values from registers 0 to 3
181  */
182 struct arm_smccc_res {
183 	unsigned long a0;
184 	unsigned long a1;
185 	unsigned long a2;
186 	unsigned long a3;
187 };
188 
189 /**
190  * struct arm_smccc_quirk - Contains quirk information
191  * @id: quirk identification
192  * @state: quirk specific information
193  * @a6: Qualcomm quirk entry for returning post-smc call contents of a6
194  */
195 struct arm_smccc_quirk {
196 	int	id;
197 	union {
198 		unsigned long a6;
199 	} state;
200 };
201 
202 /**
203  * __arm_smccc_smc() - make SMC calls
204  * @a0-a7: arguments passed in registers 0 to 7
205  * @res: result values from registers 0 to 3
206  * @quirk: points to an arm_smccc_quirk, or NULL when no quirks are required.
207  *
208  * This function is used to make SMC calls following SMC Calling Convention.
209  * The content of the supplied param are copied to registers 0 to 7 prior
210  * to the SMC instruction. The return values are updated with the content
211  * from register 0 to 3 on return from the SMC instruction.  An optional
212  * quirk structure provides vendor specific behavior.
213  */
214 asmlinkage void __arm_smccc_smc(unsigned long a0, unsigned long a1,
215 			unsigned long a2, unsigned long a3, unsigned long a4,
216 			unsigned long a5, unsigned long a6, unsigned long a7,
217 			struct arm_smccc_res *res, struct arm_smccc_quirk *quirk);
218 
219 /**
220  * __arm_smccc_hvc() - make HVC calls
221  * @a0-a7: arguments passed in registers 0 to 7
222  * @res: result values from registers 0 to 3
223  * @quirk: points to an arm_smccc_quirk, or NULL when no quirks are required.
224  *
225  * This function is used to make HVC calls following SMC Calling
226  * Convention.  The content of the supplied param are copied to registers 0
227  * to 7 prior to the HVC instruction. The return values are updated with
228  * the content from register 0 to 3 on return from the HVC instruction.  An
229  * optional quirk structure provides vendor specific behavior.
230  */
231 asmlinkage void __arm_smccc_hvc(unsigned long a0, unsigned long a1,
232 			unsigned long a2, unsigned long a3, unsigned long a4,
233 			unsigned long a5, unsigned long a6, unsigned long a7,
234 			struct arm_smccc_res *res, struct arm_smccc_quirk *quirk);
235 
236 #define arm_smccc_smc(...) __arm_smccc_smc(__VA_ARGS__, NULL)
237 
238 #define arm_smccc_smc_quirk(...) __arm_smccc_smc(__VA_ARGS__)
239 
240 #define arm_smccc_hvc(...) __arm_smccc_hvc(__VA_ARGS__, NULL)
241 
242 #define arm_smccc_hvc_quirk(...) __arm_smccc_hvc(__VA_ARGS__)
243 
244 /* SMCCC v1.1 implementation madness follows */
245 #ifdef CONFIG_ARM64
246 
247 #define SMCCC_SMC_INST	"smc	#0"
248 #define SMCCC_HVC_INST	"hvc	#0"
249 
250 #elif defined(CONFIG_ARM)
251 #include <asm/opcodes-sec.h>
252 #include <asm/opcodes-virt.h>
253 
254 #define SMCCC_SMC_INST	__SMC(0)
255 #define SMCCC_HVC_INST	__HVC(0)
256 
257 #endif
258 
259 #define ___count_args(_0, _1, _2, _3, _4, _5, _6, _7, _8, x, ...) x
260 
261 #define __count_args(...)						\
262 	___count_args(__VA_ARGS__, 7, 6, 5, 4, 3, 2, 1, 0)
263 
264 #define __constraint_read_0	"r" (arg0)
265 #define __constraint_read_1	__constraint_read_0, "r" (arg1)
266 #define __constraint_read_2	__constraint_read_1, "r" (arg2)
267 #define __constraint_read_3	__constraint_read_2, "r" (arg3)
268 #define __constraint_read_4	__constraint_read_3, "r" (arg4)
269 #define __constraint_read_5	__constraint_read_4, "r" (arg5)
270 #define __constraint_read_6	__constraint_read_5, "r" (arg6)
271 #define __constraint_read_7	__constraint_read_6, "r" (arg7)
272 
273 #define __declare_arg_0(a0, res)					\
274 	struct arm_smccc_res   *___res = res;				\
275 	register unsigned long arg0 asm("r0") = (u32)a0
276 
277 #define __declare_arg_1(a0, a1, res)					\
278 	typeof(a1) __a1 = a1;						\
279 	struct arm_smccc_res   *___res = res;				\
280 	register unsigned long arg0 asm("r0") = (u32)a0;			\
281 	register typeof(a1) arg1 asm("r1") = __a1
282 
283 #define __declare_arg_2(a0, a1, a2, res)				\
284 	typeof(a1) __a1 = a1;						\
285 	typeof(a2) __a2 = a2;						\
286 	struct arm_smccc_res   *___res = res;				\
287 	register unsigned long arg0 asm("r0") = (u32)a0;			\
288 	register typeof(a1) arg1 asm("r1") = __a1;			\
289 	register typeof(a2) arg2 asm("r2") = __a2
290 
291 #define __declare_arg_3(a0, a1, a2, a3, res)				\
292 	typeof(a1) __a1 = a1;						\
293 	typeof(a2) __a2 = a2;						\
294 	typeof(a3) __a3 = a3;						\
295 	struct arm_smccc_res   *___res = res;				\
296 	register unsigned long arg0 asm("r0") = (u32)a0;			\
297 	register typeof(a1) arg1 asm("r1") = __a1;			\
298 	register typeof(a2) arg2 asm("r2") = __a2;			\
299 	register typeof(a3) arg3 asm("r3") = __a3
300 
301 #define __declare_arg_4(a0, a1, a2, a3, a4, res)			\
302 	typeof(a4) __a4 = a4;						\
303 	__declare_arg_3(a0, a1, a2, a3, res);				\
304 	register typeof(a4) arg4 asm("r4") = __a4
305 
306 #define __declare_arg_5(a0, a1, a2, a3, a4, a5, res)			\
307 	typeof(a5) __a5 = a5;						\
308 	__declare_arg_4(a0, a1, a2, a3, a4, res);			\
309 	register typeof(a5) arg5 asm("r5") = __a5
310 
311 #define __declare_arg_6(a0, a1, a2, a3, a4, a5, a6, res)		\
312 	typeof(a6) __a6 = a6;						\
313 	__declare_arg_5(a0, a1, a2, a3, a4, a5, res);			\
314 	register typeof(a6) arg6 asm("r6") = __a6
315 
316 #define __declare_arg_7(a0, a1, a2, a3, a4, a5, a6, a7, res)		\
317 	typeof(a7) __a7 = a7;						\
318 	__declare_arg_6(a0, a1, a2, a3, a4, a5, a6, res);		\
319 	register typeof(a7) arg7 asm("r7") = __a7
320 
321 #define ___declare_args(count, ...) __declare_arg_ ## count(__VA_ARGS__)
322 #define __declare_args(count, ...)  ___declare_args(count, __VA_ARGS__)
323 
324 #define ___constraints(count)						\
325 	: __constraint_read_ ## count					\
326 	: "memory"
327 #define __constraints(count)	___constraints(count)
328 
329 /*
330  * We have an output list that is not necessarily used, and GCC feels
331  * entitled to optimise the whole sequence away. "volatile" is what
332  * makes it stick.
333  */
334 #define __arm_smccc_1_1(inst, ...)					\
335 	do {								\
336 		register unsigned long r0 asm("r0");			\
337 		register unsigned long r1 asm("r1");			\
338 		register unsigned long r2 asm("r2");			\
339 		register unsigned long r3 asm("r3"); 			\
340 		__declare_args(__count_args(__VA_ARGS__), __VA_ARGS__);	\
341 		asm volatile(inst "\n" :				\
342 			     "=r" (r0), "=r" (r1), "=r" (r2), "=r" (r3)	\
343 			     __constraints(__count_args(__VA_ARGS__)));	\
344 		if (___res)						\
345 			*___res = (typeof(*___res)){r0, r1, r2, r3};	\
346 	} while (0)
347 
348 /*
349  * arm_smccc_1_1_smc() - make an SMCCC v1.1 compliant SMC call
350  *
351  * This is a variadic macro taking one to eight source arguments, and
352  * an optional return structure.
353  *
354  * @a0-a7: arguments passed in registers 0 to 7
355  * @res: result values from registers 0 to 3
356  *
357  * This macro is used to make SMC calls following SMC Calling Convention v1.1.
358  * The content of the supplied param are copied to registers 0 to 7 prior
359  * to the SMC instruction. The return values are updated with the content
360  * from register 0 to 3 on return from the SMC instruction if not NULL.
361  */
362 #define arm_smccc_1_1_smc(...)	__arm_smccc_1_1(SMCCC_SMC_INST, __VA_ARGS__)
363 
364 /*
365  * arm_smccc_1_1_hvc() - make an SMCCC v1.1 compliant HVC call
366  *
367  * This is a variadic macro taking one to eight source arguments, and
368  * an optional return structure.
369  *
370  * @a0-a7: arguments passed in registers 0 to 7
371  * @res: result values from registers 0 to 3
372  *
373  * This macro is used to make HVC calls following SMC Calling Convention v1.1.
374  * The content of the supplied param are copied to registers 0 to 7 prior
375  * to the HVC instruction. The return values are updated with the content
376  * from register 0 to 3 on return from the HVC instruction if not NULL.
377  */
378 #define arm_smccc_1_1_hvc(...)	__arm_smccc_1_1(SMCCC_HVC_INST, __VA_ARGS__)
379 
380 /*
381  * Like arm_smccc_1_1* but always returns SMCCC_RET_NOT_SUPPORTED.
382  * Used when the SMCCC conduit is not defined. The empty asm statement
383  * avoids compiler warnings about unused variables.
384  */
385 #define __fail_smccc_1_1(...)						\
386 	do {								\
387 		__declare_args(__count_args(__VA_ARGS__), __VA_ARGS__);	\
388 		asm ("" : __constraints(__count_args(__VA_ARGS__)));	\
389 		if (___res)						\
390 			___res->a0 = SMCCC_RET_NOT_SUPPORTED;		\
391 	} while (0)
392 
393 /*
394  * arm_smccc_1_1_invoke() - make an SMCCC v1.1 compliant call
395  *
396  * This is a variadic macro taking one to eight source arguments, and
397  * an optional return structure.
398  *
399  * @a0-a7: arguments passed in registers 0 to 7
400  * @res: result values from registers 0 to 3
401  *
402  * This macro will make either an HVC call or an SMC call depending on the
403  * current SMCCC conduit. If no valid conduit is available then -1
404  * (SMCCC_RET_NOT_SUPPORTED) is returned in @res.a0 (if supplied).
405  *
406  * The return value also provides the conduit that was used.
407  */
408 #define arm_smccc_1_1_invoke(...) ({					\
409 		int method = arm_smccc_1_1_get_conduit();		\
410 		switch (method) {					\
411 		case SMCCC_CONDUIT_HVC:					\
412 			arm_smccc_1_1_hvc(__VA_ARGS__);			\
413 			break;						\
414 		case SMCCC_CONDUIT_SMC:					\
415 			arm_smccc_1_1_smc(__VA_ARGS__);			\
416 			break;						\
417 		default:						\
418 			__fail_smccc_1_1(__VA_ARGS__);			\
419 			method = SMCCC_CONDUIT_NONE;			\
420 			break;						\
421 		}							\
422 		method;							\
423 	})
424 
425 #endif /*__ASSEMBLY__*/
426 #endif /*__LINUX_ARM_SMCCC_H*/
427