xref: /linux-6.15/include/linux/arm-smccc.h (revision b8e2c8bb)
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_SOC_ID						\
75 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,				\
76 			   ARM_SMCCC_SMC_32,				\
77 			   0, 2)
78 
79 #define ARM_SMCCC_ARCH_WORKAROUND_1					\
80 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,				\
81 			   ARM_SMCCC_SMC_32,				\
82 			   0, 0x8000)
83 
84 #define ARM_SMCCC_ARCH_WORKAROUND_2					\
85 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,				\
86 			   ARM_SMCCC_SMC_32,				\
87 			   0, 0x7fff)
88 
89 /* Paravirtualised time calls (defined by ARM DEN0057A) */
90 #define ARM_SMCCC_HV_PV_TIME_FEATURES				\
91 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,			\
92 			   ARM_SMCCC_SMC_64,			\
93 			   ARM_SMCCC_OWNER_STANDARD_HYP,	\
94 			   0x20)
95 
96 #define ARM_SMCCC_HV_PV_TIME_ST					\
97 	ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL,			\
98 			   ARM_SMCCC_SMC_64,			\
99 			   ARM_SMCCC_OWNER_STANDARD_HYP,	\
100 			   0x21)
101 
102 /*
103  * Return codes defined in ARM DEN 0070A
104  * ARM DEN 0070A is now merged/consolidated into ARM DEN 0028 C
105  */
106 #define SMCCC_RET_SUCCESS			0
107 #define SMCCC_RET_NOT_SUPPORTED			-1
108 #define SMCCC_RET_NOT_REQUIRED			-2
109 #define SMCCC_RET_INVALID_PARAMETER		-3
110 
111 #ifndef __ASSEMBLY__
112 
113 #include <linux/linkage.h>
114 #include <linux/types.h>
115 
116 enum arm_smccc_conduit {
117 	SMCCC_CONDUIT_NONE,
118 	SMCCC_CONDUIT_SMC,
119 	SMCCC_CONDUIT_HVC,
120 };
121 
122 /**
123  * arm_smccc_1_1_get_conduit()
124  *
125  * Returns the conduit to be used for SMCCCv1.1 or later.
126  *
127  * When SMCCCv1.1 is not present, returns SMCCC_CONDUIT_NONE.
128  */
129 enum arm_smccc_conduit arm_smccc_1_1_get_conduit(void);
130 
131 /**
132  * arm_smccc_get_version()
133  *
134  * Returns the version to be used for SMCCCv1.1 or later.
135  *
136  * When SMCCCv1.1 or above is not present, returns SMCCCv1.0, but this
137  * does not imply the presence of firmware or a valid conduit. Caller
138  * handling SMCCCv1.0 must determine the conduit by other means.
139  */
140 u32 arm_smccc_get_version(void);
141 
142 void __init arm_smccc_version_init(u32 version, enum arm_smccc_conduit conduit);
143 
144 /**
145  * struct arm_smccc_res - Result from SMC/HVC call
146  * @a0-a3 result values from registers 0 to 3
147  */
148 struct arm_smccc_res {
149 	unsigned long a0;
150 	unsigned long a1;
151 	unsigned long a2;
152 	unsigned long a3;
153 };
154 
155 /**
156  * struct arm_smccc_quirk - Contains quirk information
157  * @id: quirk identification
158  * @state: quirk specific information
159  * @a6: Qualcomm quirk entry for returning post-smc call contents of a6
160  */
161 struct arm_smccc_quirk {
162 	int	id;
163 	union {
164 		unsigned long a6;
165 	} state;
166 };
167 
168 /**
169  * __arm_smccc_smc() - make SMC calls
170  * @a0-a7: arguments passed in registers 0 to 7
171  * @res: result values from registers 0 to 3
172  * @quirk: points to an arm_smccc_quirk, or NULL when no quirks are required.
173  *
174  * This function is used to make SMC calls following SMC Calling Convention.
175  * The content of the supplied param are copied to registers 0 to 7 prior
176  * to the SMC instruction. The return values are updated with the content
177  * from register 0 to 3 on return from the SMC instruction.  An optional
178  * quirk structure provides vendor specific behavior.
179  */
180 asmlinkage void __arm_smccc_smc(unsigned long a0, unsigned long a1,
181 			unsigned long a2, unsigned long a3, unsigned long a4,
182 			unsigned long a5, unsigned long a6, unsigned long a7,
183 			struct arm_smccc_res *res, struct arm_smccc_quirk *quirk);
184 
185 /**
186  * __arm_smccc_hvc() - make HVC calls
187  * @a0-a7: arguments passed in registers 0 to 7
188  * @res: result values from registers 0 to 3
189  * @quirk: points to an arm_smccc_quirk, or NULL when no quirks are required.
190  *
191  * This function is used to make HVC calls following SMC Calling
192  * Convention.  The content of the supplied param are copied to registers 0
193  * to 7 prior to the HVC instruction. The return values are updated with
194  * the content from register 0 to 3 on return from the HVC instruction.  An
195  * optional quirk structure provides vendor specific behavior.
196  */
197 asmlinkage void __arm_smccc_hvc(unsigned long a0, unsigned long a1,
198 			unsigned long a2, unsigned long a3, unsigned long a4,
199 			unsigned long a5, unsigned long a6, unsigned long a7,
200 			struct arm_smccc_res *res, struct arm_smccc_quirk *quirk);
201 
202 #define arm_smccc_smc(...) __arm_smccc_smc(__VA_ARGS__, NULL)
203 
204 #define arm_smccc_smc_quirk(...) __arm_smccc_smc(__VA_ARGS__)
205 
206 #define arm_smccc_hvc(...) __arm_smccc_hvc(__VA_ARGS__, NULL)
207 
208 #define arm_smccc_hvc_quirk(...) __arm_smccc_hvc(__VA_ARGS__)
209 
210 /* SMCCC v1.1 implementation madness follows */
211 #ifdef CONFIG_ARM64
212 
213 #define SMCCC_SMC_INST	"smc	#0"
214 #define SMCCC_HVC_INST	"hvc	#0"
215 
216 #elif defined(CONFIG_ARM)
217 #include <asm/opcodes-sec.h>
218 #include <asm/opcodes-virt.h>
219 
220 #define SMCCC_SMC_INST	__SMC(0)
221 #define SMCCC_HVC_INST	__HVC(0)
222 
223 #endif
224 
225 #define ___count_args(_0, _1, _2, _3, _4, _5, _6, _7, _8, x, ...) x
226 
227 #define __count_args(...)						\
228 	___count_args(__VA_ARGS__, 7, 6, 5, 4, 3, 2, 1, 0)
229 
230 #define __constraint_write_0						\
231 	"+r" (r0), "=&r" (r1), "=&r" (r2), "=&r" (r3)
232 #define __constraint_write_1						\
233 	"+r" (r0), "+r" (r1), "=&r" (r2), "=&r" (r3)
234 #define __constraint_write_2						\
235 	"+r" (r0), "+r" (r1), "+r" (r2), "=&r" (r3)
236 #define __constraint_write_3						\
237 	"+r" (r0), "+r" (r1), "+r" (r2), "+r" (r3)
238 #define __constraint_write_4	__constraint_write_3
239 #define __constraint_write_5	__constraint_write_4
240 #define __constraint_write_6	__constraint_write_5
241 #define __constraint_write_7	__constraint_write_6
242 
243 #define __constraint_read_0
244 #define __constraint_read_1
245 #define __constraint_read_2
246 #define __constraint_read_3
247 #define __constraint_read_4	"r" (r4)
248 #define __constraint_read_5	__constraint_read_4, "r" (r5)
249 #define __constraint_read_6	__constraint_read_5, "r" (r6)
250 #define __constraint_read_7	__constraint_read_6, "r" (r7)
251 
252 #define __declare_arg_0(a0, res)					\
253 	struct arm_smccc_res   *___res = res;				\
254 	register unsigned long r0 asm("r0") = (u32)a0;			\
255 	register unsigned long r1 asm("r1");				\
256 	register unsigned long r2 asm("r2");				\
257 	register unsigned long r3 asm("r3")
258 
259 #define __declare_arg_1(a0, a1, res)					\
260 	typeof(a1) __a1 = a1;						\
261 	struct arm_smccc_res   *___res = res;				\
262 	register unsigned long r0 asm("r0") = (u32)a0;			\
263 	register unsigned long r1 asm("r1") = __a1;			\
264 	register unsigned long r2 asm("r2");				\
265 	register unsigned long r3 asm("r3")
266 
267 #define __declare_arg_2(a0, a1, a2, res)				\
268 	typeof(a1) __a1 = a1;						\
269 	typeof(a2) __a2 = a2;						\
270 	struct arm_smccc_res   *___res = res;				\
271 	register unsigned long r0 asm("r0") = (u32)a0;			\
272 	register unsigned long r1 asm("r1") = __a1;			\
273 	register unsigned long r2 asm("r2") = __a2;			\
274 	register unsigned long r3 asm("r3")
275 
276 #define __declare_arg_3(a0, a1, a2, a3, res)				\
277 	typeof(a1) __a1 = a1;						\
278 	typeof(a2) __a2 = a2;						\
279 	typeof(a3) __a3 = a3;						\
280 	struct arm_smccc_res   *___res = res;				\
281 	register unsigned long r0 asm("r0") = (u32)a0;			\
282 	register unsigned long r1 asm("r1") = __a1;			\
283 	register unsigned long r2 asm("r2") = __a2;			\
284 	register unsigned long r3 asm("r3") = __a3
285 
286 #define __declare_arg_4(a0, a1, a2, a3, a4, res)			\
287 	typeof(a4) __a4 = a4;						\
288 	__declare_arg_3(a0, a1, a2, a3, res);				\
289 	register unsigned long r4 asm("r4") = __a4
290 
291 #define __declare_arg_5(a0, a1, a2, a3, a4, a5, res)			\
292 	typeof(a5) __a5 = a5;						\
293 	__declare_arg_4(a0, a1, a2, a3, a4, res);			\
294 	register unsigned long r5 asm("r5") = __a5
295 
296 #define __declare_arg_6(a0, a1, a2, a3, a4, a5, a6, res)		\
297 	typeof(a6) __a6 = a6;						\
298 	__declare_arg_5(a0, a1, a2, a3, a4, a5, res);			\
299 	register unsigned long r6 asm("r6") = __a6
300 
301 #define __declare_arg_7(a0, a1, a2, a3, a4, a5, a6, a7, res)		\
302 	typeof(a7) __a7 = a7;						\
303 	__declare_arg_6(a0, a1, a2, a3, a4, a5, a6, res);		\
304 	register unsigned long r7 asm("r7") = __a7
305 
306 #define ___declare_args(count, ...) __declare_arg_ ## count(__VA_ARGS__)
307 #define __declare_args(count, ...)  ___declare_args(count, __VA_ARGS__)
308 
309 #define ___constraints(count)						\
310 	: __constraint_write_ ## count					\
311 	: __constraint_read_ ## count					\
312 	: "memory"
313 #define __constraints(count)	___constraints(count)
314 
315 /*
316  * We have an output list that is not necessarily used, and GCC feels
317  * entitled to optimise the whole sequence away. "volatile" is what
318  * makes it stick.
319  */
320 #define __arm_smccc_1_1(inst, ...)					\
321 	do {								\
322 		__declare_args(__count_args(__VA_ARGS__), __VA_ARGS__);	\
323 		asm volatile(inst "\n"					\
324 			     __constraints(__count_args(__VA_ARGS__)));	\
325 		if (___res)						\
326 			*___res = (typeof(*___res)){r0, r1, r2, r3};	\
327 	} while (0)
328 
329 /*
330  * arm_smccc_1_1_smc() - make an SMCCC v1.1 compliant SMC call
331  *
332  * This is a variadic macro taking one to eight source arguments, and
333  * an optional return structure.
334  *
335  * @a0-a7: arguments passed in registers 0 to 7
336  * @res: result values from registers 0 to 3
337  *
338  * This macro is used to make SMC calls following SMC Calling Convention v1.1.
339  * The content of the supplied param are copied to registers 0 to 7 prior
340  * to the SMC instruction. The return values are updated with the content
341  * from register 0 to 3 on return from the SMC instruction if not NULL.
342  */
343 #define arm_smccc_1_1_smc(...)	__arm_smccc_1_1(SMCCC_SMC_INST, __VA_ARGS__)
344 
345 /*
346  * arm_smccc_1_1_hvc() - make an SMCCC v1.1 compliant HVC call
347  *
348  * This is a variadic macro taking one to eight source arguments, and
349  * an optional return structure.
350  *
351  * @a0-a7: arguments passed in registers 0 to 7
352  * @res: result values from registers 0 to 3
353  *
354  * This macro is used to make HVC calls following SMC Calling Convention v1.1.
355  * The content of the supplied param are copied to registers 0 to 7 prior
356  * to the HVC instruction. The return values are updated with the content
357  * from register 0 to 3 on return from the HVC instruction if not NULL.
358  */
359 #define arm_smccc_1_1_hvc(...)	__arm_smccc_1_1(SMCCC_HVC_INST, __VA_ARGS__)
360 
361 /*
362  * Like arm_smccc_1_1* but always returns SMCCC_RET_NOT_SUPPORTED.
363  * Used when the SMCCC conduit is not defined. The empty asm statement
364  * avoids compiler warnings about unused variables.
365  */
366 #define __fail_smccc_1_1(...)						\
367 	do {								\
368 		__declare_args(__count_args(__VA_ARGS__), __VA_ARGS__);	\
369 		asm ("" __constraints(__count_args(__VA_ARGS__)));	\
370 		if (___res)						\
371 			___res->a0 = SMCCC_RET_NOT_SUPPORTED;		\
372 	} while (0)
373 
374 /*
375  * arm_smccc_1_1_invoke() - make an SMCCC v1.1 compliant call
376  *
377  * This is a variadic macro taking one to eight source arguments, and
378  * an optional return structure.
379  *
380  * @a0-a7: arguments passed in registers 0 to 7
381  * @res: result values from registers 0 to 3
382  *
383  * This macro will make either an HVC call or an SMC call depending on the
384  * current SMCCC conduit. If no valid conduit is available then -1
385  * (SMCCC_RET_NOT_SUPPORTED) is returned in @res.a0 (if supplied).
386  *
387  * The return value also provides the conduit that was used.
388  */
389 #define arm_smccc_1_1_invoke(...) ({					\
390 		int method = arm_smccc_1_1_get_conduit();		\
391 		switch (method) {					\
392 		case SMCCC_CONDUIT_HVC:					\
393 			arm_smccc_1_1_hvc(__VA_ARGS__);			\
394 			break;						\
395 		case SMCCC_CONDUIT_SMC:					\
396 			arm_smccc_1_1_smc(__VA_ARGS__);			\
397 			break;						\
398 		default:						\
399 			__fail_smccc_1_1(__VA_ARGS__);			\
400 			method = SMCCC_CONDUIT_NONE;			\
401 			break;						\
402 		}							\
403 		method;							\
404 	})
405 
406 #endif /*__ASSEMBLY__*/
407 #endif /*__LINUX_ARM_SMCCC_H*/
408