xref: /linux-6.15/include/linux/arm-smccc.h (revision bb79974c)
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_TRUSTED_APP	48
53 #define ARM_SMCCC_OWNER_TRUSTED_APP_END	49
54 #define ARM_SMCCC_OWNER_TRUSTED_OS	50
55 #define ARM_SMCCC_OWNER_TRUSTED_OS_END	63
56 
57 #define ARM_SMCCC_QUIRK_NONE		0
58 #define ARM_SMCCC_QUIRK_QCOM_A6		1 /* Save/restore register a6 */
59 
60 #define ARM_SMCCC_VERSION_1_0		0x10000
61 #define ARM_SMCCC_VERSION_1_1		0x10001
62 #define ARM_SMCCC_VERSION_1_2		0x10002
63 
64 #define ARM_SMCCC_VERSION_FUNC_ID					\
65 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,				\
66 			   ARM_SMCCC_SMC_32,				\
67 			   0, 0)
68 
69 #define ARM_SMCCC_ARCH_FEATURES_FUNC_ID					\
70 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,				\
71 			   ARM_SMCCC_SMC_32,				\
72 			   0, 1)
73 
74 #define ARM_SMCCC_ARCH_WORKAROUND_1					\
75 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,				\
76 			   ARM_SMCCC_SMC_32,				\
77 			   0, 0x8000)
78 
79 #define ARM_SMCCC_ARCH_WORKAROUND_2					\
80 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,				\
81 			   ARM_SMCCC_SMC_32,				\
82 			   0, 0x7fff)
83 
84 #ifndef __ASSEMBLY__
85 
86 #include <linux/linkage.h>
87 #include <linux/types.h>
88 
89 enum arm_smccc_conduit {
90 	SMCCC_CONDUIT_NONE,
91 	SMCCC_CONDUIT_SMC,
92 	SMCCC_CONDUIT_HVC,
93 };
94 
95 /**
96  * arm_smccc_1_1_get_conduit()
97  *
98  * Returns the conduit to be used for SMCCCv1.1 or later.
99  *
100  * When SMCCCv1.1 is not present, returns SMCCC_CONDUIT_NONE.
101  */
102 enum arm_smccc_conduit arm_smccc_1_1_get_conduit(void);
103 
104 /**
105  * arm_smccc_get_version()
106  *
107  * Returns the version to be used for SMCCCv1.1 or later.
108  *
109  * When SMCCCv1.1 or above is not present, returns SMCCCv1.0, but this
110  * does not imply the presence of firmware or a valid conduit. Caller
111  * handling SMCCCv1.0 must determine the conduit by other means.
112  */
113 u32 arm_smccc_get_version(void);
114 
115 void __init arm_smccc_version_init(u32 version, enum arm_smccc_conduit conduit);
116 
117 /**
118  * struct arm_smccc_res - Result from SMC/HVC call
119  * @a0-a3 result values from registers 0 to 3
120  */
121 struct arm_smccc_res {
122 	unsigned long a0;
123 	unsigned long a1;
124 	unsigned long a2;
125 	unsigned long a3;
126 };
127 
128 /**
129  * struct arm_smccc_quirk - Contains quirk information
130  * @id: quirk identification
131  * @state: quirk specific information
132  * @a6: Qualcomm quirk entry for returning post-smc call contents of a6
133  */
134 struct arm_smccc_quirk {
135 	int	id;
136 	union {
137 		unsigned long a6;
138 	} state;
139 };
140 
141 /**
142  * __arm_smccc_smc() - make SMC calls
143  * @a0-a7: arguments passed in registers 0 to 7
144  * @res: result values from registers 0 to 3
145  * @quirk: points to an arm_smccc_quirk, or NULL when no quirks are required.
146  *
147  * This function is used to make SMC calls following SMC Calling Convention.
148  * The content of the supplied param are copied to registers 0 to 7 prior
149  * to the SMC instruction. The return values are updated with the content
150  * from register 0 to 3 on return from the SMC instruction.  An optional
151  * quirk structure provides vendor specific behavior.
152  */
153 asmlinkage void __arm_smccc_smc(unsigned long a0, unsigned long a1,
154 			unsigned long a2, unsigned long a3, unsigned long a4,
155 			unsigned long a5, unsigned long a6, unsigned long a7,
156 			struct arm_smccc_res *res, struct arm_smccc_quirk *quirk);
157 
158 /**
159  * __arm_smccc_hvc() - make HVC calls
160  * @a0-a7: arguments passed in registers 0 to 7
161  * @res: result values from registers 0 to 3
162  * @quirk: points to an arm_smccc_quirk, or NULL when no quirks are required.
163  *
164  * This function is used to make HVC calls following SMC Calling
165  * Convention.  The content of the supplied param are copied to registers 0
166  * to 7 prior to the HVC instruction. The return values are updated with
167  * the content from register 0 to 3 on return from the HVC instruction.  An
168  * optional quirk structure provides vendor specific behavior.
169  */
170 asmlinkage void __arm_smccc_hvc(unsigned long a0, unsigned long a1,
171 			unsigned long a2, unsigned long a3, unsigned long a4,
172 			unsigned long a5, unsigned long a6, unsigned long a7,
173 			struct arm_smccc_res *res, struct arm_smccc_quirk *quirk);
174 
175 #define arm_smccc_smc(...) __arm_smccc_smc(__VA_ARGS__, NULL)
176 
177 #define arm_smccc_smc_quirk(...) __arm_smccc_smc(__VA_ARGS__)
178 
179 #define arm_smccc_hvc(...) __arm_smccc_hvc(__VA_ARGS__, NULL)
180 
181 #define arm_smccc_hvc_quirk(...) __arm_smccc_hvc(__VA_ARGS__)
182 
183 /* SMCCC v1.1 implementation madness follows */
184 #ifdef CONFIG_ARM64
185 
186 #define SMCCC_SMC_INST	"smc	#0"
187 #define SMCCC_HVC_INST	"hvc	#0"
188 
189 #elif defined(CONFIG_ARM)
190 #include <asm/opcodes-sec.h>
191 #include <asm/opcodes-virt.h>
192 
193 #define SMCCC_SMC_INST	__SMC(0)
194 #define SMCCC_HVC_INST	__HVC(0)
195 
196 #endif
197 
198 #define ___count_args(_0, _1, _2, _3, _4, _5, _6, _7, _8, x, ...) x
199 
200 #define __count_args(...)						\
201 	___count_args(__VA_ARGS__, 7, 6, 5, 4, 3, 2, 1, 0)
202 
203 #define __constraint_write_0						\
204 	"+r" (r0), "=&r" (r1), "=&r" (r2), "=&r" (r3)
205 #define __constraint_write_1						\
206 	"+r" (r0), "+r" (r1), "=&r" (r2), "=&r" (r3)
207 #define __constraint_write_2						\
208 	"+r" (r0), "+r" (r1), "+r" (r2), "=&r" (r3)
209 #define __constraint_write_3						\
210 	"+r" (r0), "+r" (r1), "+r" (r2), "+r" (r3)
211 #define __constraint_write_4	__constraint_write_3
212 #define __constraint_write_5	__constraint_write_4
213 #define __constraint_write_6	__constraint_write_5
214 #define __constraint_write_7	__constraint_write_6
215 
216 #define __constraint_read_0
217 #define __constraint_read_1
218 #define __constraint_read_2
219 #define __constraint_read_3
220 #define __constraint_read_4	"r" (r4)
221 #define __constraint_read_5	__constraint_read_4, "r" (r5)
222 #define __constraint_read_6	__constraint_read_5, "r" (r6)
223 #define __constraint_read_7	__constraint_read_6, "r" (r7)
224 
225 #define __declare_arg_0(a0, res)					\
226 	struct arm_smccc_res   *___res = res;				\
227 	register unsigned long r0 asm("r0") = (u32)a0;			\
228 	register unsigned long r1 asm("r1");				\
229 	register unsigned long r2 asm("r2");				\
230 	register unsigned long r3 asm("r3")
231 
232 #define __declare_arg_1(a0, a1, res)					\
233 	typeof(a1) __a1 = a1;						\
234 	struct arm_smccc_res   *___res = res;				\
235 	register unsigned long r0 asm("r0") = (u32)a0;			\
236 	register unsigned long r1 asm("r1") = __a1;			\
237 	register unsigned long r2 asm("r2");				\
238 	register unsigned long r3 asm("r3")
239 
240 #define __declare_arg_2(a0, a1, a2, res)				\
241 	typeof(a1) __a1 = a1;						\
242 	typeof(a2) __a2 = a2;						\
243 	struct arm_smccc_res   *___res = res;				\
244 	register unsigned long r0 asm("r0") = (u32)a0;			\
245 	register unsigned long r1 asm("r1") = __a1;			\
246 	register unsigned long r2 asm("r2") = __a2;			\
247 	register unsigned long r3 asm("r3")
248 
249 #define __declare_arg_3(a0, a1, a2, a3, res)				\
250 	typeof(a1) __a1 = a1;						\
251 	typeof(a2) __a2 = a2;						\
252 	typeof(a3) __a3 = a3;						\
253 	struct arm_smccc_res   *___res = res;				\
254 	register unsigned long r0 asm("r0") = (u32)a0;			\
255 	register unsigned long r1 asm("r1") = __a1;			\
256 	register unsigned long r2 asm("r2") = __a2;			\
257 	register unsigned long r3 asm("r3") = __a3
258 
259 #define __declare_arg_4(a0, a1, a2, a3, a4, res)			\
260 	typeof(a4) __a4 = a4;						\
261 	__declare_arg_3(a0, a1, a2, a3, res);				\
262 	register unsigned long r4 asm("r4") = __a4
263 
264 #define __declare_arg_5(a0, a1, a2, a3, a4, a5, res)			\
265 	typeof(a5) __a5 = a5;						\
266 	__declare_arg_4(a0, a1, a2, a3, a4, res);			\
267 	register unsigned long r5 asm("r5") = __a5
268 
269 #define __declare_arg_6(a0, a1, a2, a3, a4, a5, a6, res)		\
270 	typeof(a6) __a6 = a6;						\
271 	__declare_arg_5(a0, a1, a2, a3, a4, a5, res);			\
272 	register unsigned long r6 asm("r6") = __a6
273 
274 #define __declare_arg_7(a0, a1, a2, a3, a4, a5, a6, a7, res)		\
275 	typeof(a7) __a7 = a7;						\
276 	__declare_arg_6(a0, a1, a2, a3, a4, a5, a6, res);		\
277 	register unsigned long r7 asm("r7") = __a7
278 
279 #define ___declare_args(count, ...) __declare_arg_ ## count(__VA_ARGS__)
280 #define __declare_args(count, ...)  ___declare_args(count, __VA_ARGS__)
281 
282 #define ___constraints(count)						\
283 	: __constraint_write_ ## count					\
284 	: __constraint_read_ ## count					\
285 	: "memory"
286 #define __constraints(count)	___constraints(count)
287 
288 /*
289  * We have an output list that is not necessarily used, and GCC feels
290  * entitled to optimise the whole sequence away. "volatile" is what
291  * makes it stick.
292  */
293 #define __arm_smccc_1_1(inst, ...)					\
294 	do {								\
295 		__declare_args(__count_args(__VA_ARGS__), __VA_ARGS__);	\
296 		asm volatile(inst "\n"					\
297 			     __constraints(__count_args(__VA_ARGS__)));	\
298 		if (___res)						\
299 			*___res = (typeof(*___res)){r0, r1, r2, r3};	\
300 	} while (0)
301 
302 /*
303  * arm_smccc_1_1_smc() - make an SMCCC v1.1 compliant SMC call
304  *
305  * This is a variadic macro taking one to eight source arguments, and
306  * an optional return structure.
307  *
308  * @a0-a7: arguments passed in registers 0 to 7
309  * @res: result values from registers 0 to 3
310  *
311  * This macro is used to make SMC calls following SMC Calling Convention v1.1.
312  * The content of the supplied param are copied to registers 0 to 7 prior
313  * to the SMC instruction. The return values are updated with the content
314  * from register 0 to 3 on return from the SMC instruction if not NULL.
315  */
316 #define arm_smccc_1_1_smc(...)	__arm_smccc_1_1(SMCCC_SMC_INST, __VA_ARGS__)
317 
318 /*
319  * arm_smccc_1_1_hvc() - make an SMCCC v1.1 compliant HVC call
320  *
321  * This is a variadic macro taking one to eight source arguments, and
322  * an optional return structure.
323  *
324  * @a0-a7: arguments passed in registers 0 to 7
325  * @res: result values from registers 0 to 3
326  *
327  * This macro is used to make HVC calls following SMC Calling Convention v1.1.
328  * The content of the supplied param are copied to registers 0 to 7 prior
329  * to the HVC instruction. The return values are updated with the content
330  * from register 0 to 3 on return from the HVC instruction if not NULL.
331  */
332 #define arm_smccc_1_1_hvc(...)	__arm_smccc_1_1(SMCCC_HVC_INST, __VA_ARGS__)
333 
334 /*
335  * Return codes defined in ARM DEN 0070A
336  * ARM DEN 0070A is now merged/consolidated into ARM DEN 0028 C
337  */
338 #define SMCCC_RET_SUCCESS			0
339 #define SMCCC_RET_NOT_SUPPORTED			-1
340 #define SMCCC_RET_NOT_REQUIRED			-2
341 #define SMCCC_RET_INVALID_PARAMETER		-3
342 
343 /*
344  * Like arm_smccc_1_1* but always returns SMCCC_RET_NOT_SUPPORTED.
345  * Used when the SMCCC conduit is not defined. The empty asm statement
346  * avoids compiler warnings about unused variables.
347  */
348 #define __fail_smccc_1_1(...)						\
349 	do {								\
350 		__declare_args(__count_args(__VA_ARGS__), __VA_ARGS__);	\
351 		asm ("" __constraints(__count_args(__VA_ARGS__)));	\
352 		if (___res)						\
353 			___res->a0 = SMCCC_RET_NOT_SUPPORTED;		\
354 	} while (0)
355 
356 /*
357  * arm_smccc_1_1_invoke() - make an SMCCC v1.1 compliant call
358  *
359  * This is a variadic macro taking one to eight source arguments, and
360  * an optional return structure.
361  *
362  * @a0-a7: arguments passed in registers 0 to 7
363  * @res: result values from registers 0 to 3
364  *
365  * This macro will make either an HVC call or an SMC call depending on the
366  * current SMCCC conduit. If no valid conduit is available then -1
367  * (SMCCC_RET_NOT_SUPPORTED) is returned in @res.a0 (if supplied).
368  *
369  * The return value also provides the conduit that was used.
370  */
371 #define arm_smccc_1_1_invoke(...) ({					\
372 		int method = arm_smccc_1_1_get_conduit();		\
373 		switch (method) {					\
374 		case SMCCC_CONDUIT_HVC:					\
375 			arm_smccc_1_1_hvc(__VA_ARGS__);			\
376 			break;						\
377 		case SMCCC_CONDUIT_SMC:					\
378 			arm_smccc_1_1_smc(__VA_ARGS__);			\
379 			break;						\
380 		default:						\
381 			__fail_smccc_1_1(__VA_ARGS__);			\
382 			method = SMCCC_CONDUIT_NONE;			\
383 			break;						\
384 		}							\
385 		method;							\
386 	})
387 
388 /* Paravirtualised time calls (defined by ARM DEN0057A) */
389 #define ARM_SMCCC_HV_PV_TIME_FEATURES				\
390 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,			\
391 			   ARM_SMCCC_SMC_64,			\
392 			   ARM_SMCCC_OWNER_STANDARD_HYP,	\
393 			   0x20)
394 
395 #define ARM_SMCCC_HV_PV_TIME_ST					\
396 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,			\
397 			   ARM_SMCCC_SMC_64,			\
398 			   ARM_SMCCC_OWNER_STANDARD_HYP,	\
399 			   0x21)
400 
401 #endif /*__ASSEMBLY__*/
402 #endif /*__LINUX_ARM_SMCCC_H*/
403