xref: /linux/tools/testing/selftests/kvm/arm64/set_id_regs.c (revision 7fc2cd2e4b398c57c9cf961cfea05eadbf34c05c)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * set_id_regs - Test for setting ID register from usersapce.
4  *
5  * Copyright (c) 2023 Google LLC.
6  *
7  *
8  * Test that KVM supports setting ID registers from userspace and handles the
9  * feature set correctly.
10  */
11 
12 #include <stdint.h>
13 #include "kvm_util.h"
14 #include "processor.h"
15 #include "test_util.h"
16 #include <linux/bitfield.h>
17 
18 enum ftr_type {
19 	FTR_EXACT,			/* Use a predefined safe value */
20 	FTR_LOWER_SAFE,			/* Smaller value is safe */
21 	FTR_HIGHER_SAFE,		/* Bigger value is safe */
22 	FTR_HIGHER_OR_ZERO_SAFE,	/* Bigger value is safe, but 0 is biggest */
23 	FTR_END,			/* Mark the last ftr bits */
24 };
25 
26 #define FTR_SIGNED	true	/* Value should be treated as signed */
27 #define FTR_UNSIGNED	false	/* Value should be treated as unsigned */
28 
29 struct reg_ftr_bits {
30 	char *name;
31 	bool sign;
32 	enum ftr_type type;
33 	uint8_t shift;
34 	uint64_t mask;
35 	/*
36 	 * For FTR_EXACT, safe_val is used as the exact safe value.
37 	 * For FTR_LOWER_SAFE, safe_val is used as the minimal safe value.
38 	 */
39 	int64_t safe_val;
40 };
41 
42 struct test_feature_reg {
43 	uint32_t reg;
44 	const struct reg_ftr_bits *ftr_bits;
45 };
46 
47 #define __REG_FTR_BITS(NAME, SIGNED, TYPE, SHIFT, MASK, SAFE_VAL)	\
48 	{								\
49 		.name = #NAME,						\
50 		.sign = SIGNED,						\
51 		.type = TYPE,						\
52 		.shift = SHIFT,						\
53 		.mask = MASK,						\
54 		.safe_val = SAFE_VAL,					\
55 	}
56 
57 #define REG_FTR_BITS(type, reg, field, safe_val) \
58 	__REG_FTR_BITS(reg##_##field, FTR_UNSIGNED, type, reg##_##field##_SHIFT, \
59 		       reg##_##field##_MASK, safe_val)
60 
61 #define S_REG_FTR_BITS(type, reg, field, safe_val) \
62 	__REG_FTR_BITS(reg##_##field, FTR_SIGNED, type, reg##_##field##_SHIFT, \
63 		       reg##_##field##_MASK, safe_val)
64 
65 #define REG_FTR_END					\
66 	{						\
67 		.type = FTR_END,			\
68 	}
69 
70 static const struct reg_ftr_bits ftr_id_aa64dfr0_el1[] = {
71 	S_REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64DFR0_EL1, DoubleLock, 0),
72 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64DFR0_EL1, WRPs, 0),
73 	S_REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64DFR0_EL1, PMUVer, 0),
74 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64DFR0_EL1, DebugVer, ID_AA64DFR0_EL1_DebugVer_IMP),
75 	REG_FTR_END,
76 };
77 
78 static const struct reg_ftr_bits ftr_id_dfr0_el1[] = {
79 	S_REG_FTR_BITS(FTR_LOWER_SAFE, ID_DFR0_EL1, PerfMon, ID_DFR0_EL1_PerfMon_PMUv3),
80 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_DFR0_EL1, CopDbg, ID_DFR0_EL1_CopDbg_Armv8),
81 	REG_FTR_END,
82 };
83 
84 static const struct reg_ftr_bits ftr_id_aa64isar0_el1[] = {
85 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, RNDR, 0),
86 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, TLB, 0),
87 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, TS, 0),
88 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, FHM, 0),
89 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, DP, 0),
90 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, SM4, 0),
91 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, SM3, 0),
92 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, SHA3, 0),
93 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, RDM, 0),
94 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, TME, 0),
95 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, ATOMIC, 0),
96 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, CRC32, 0),
97 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, SHA2, 0),
98 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, SHA1, 0),
99 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR0_EL1, AES, 0),
100 	REG_FTR_END,
101 };
102 
103 static const struct reg_ftr_bits ftr_id_aa64isar1_el1[] = {
104 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, LS64, 0),
105 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, XS, 0),
106 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, I8MM, 0),
107 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, DGH, 0),
108 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, BF16, 0),
109 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, SPECRES, 0),
110 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, SB, 0),
111 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, FRINTTS, 0),
112 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, LRCPC, 0),
113 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, FCMA, 0),
114 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, JSCVT, 0),
115 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR1_EL1, DPB, 0),
116 	REG_FTR_END,
117 };
118 
119 static const struct reg_ftr_bits ftr_id_aa64isar2_el1[] = {
120 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR2_EL1, BC, 0),
121 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR2_EL1, RPRES, 0),
122 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR2_EL1, WFxT, 0),
123 	REG_FTR_END,
124 };
125 
126 static const struct reg_ftr_bits ftr_id_aa64isar3_el1[] = {
127 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR3_EL1, FPRCVT, 0),
128 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR3_EL1, LSFE, 0),
129 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ISAR3_EL1, FAMINMAX, 0),
130 	REG_FTR_END,
131 };
132 
133 static const struct reg_ftr_bits ftr_id_aa64pfr0_el1[] = {
134 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, CSV3, 0),
135 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, CSV2, 0),
136 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, DIT, 0),
137 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, SEL2, 0),
138 	REG_FTR_BITS(FTR_EXACT, ID_AA64PFR0_EL1, GIC, 0),
139 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, EL3, 1),
140 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, EL2, 1),
141 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, EL1, 1),
142 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, EL0, 1),
143 	REG_FTR_END,
144 };
145 
146 static const struct reg_ftr_bits ftr_id_aa64pfr1_el1[] = {
147 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR1_EL1, DF2, 0),
148 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR1_EL1, CSV2_frac, 0),
149 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR1_EL1, SSBS, ID_AA64PFR1_EL1_SSBS_NI),
150 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR1_EL1, BT, 0),
151 	REG_FTR_END,
152 };
153 
154 static const struct reg_ftr_bits ftr_id_aa64mmfr0_el1[] = {
155 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, ECV, 0),
156 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, EXS, 0),
157 	REG_FTR_BITS(FTR_EXACT, ID_AA64MMFR0_EL1, TGRAN4_2, 1),
158 	REG_FTR_BITS(FTR_EXACT, ID_AA64MMFR0_EL1, TGRAN64_2, 1),
159 	REG_FTR_BITS(FTR_EXACT, ID_AA64MMFR0_EL1, TGRAN16_2, 1),
160 	S_REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, TGRAN4, 0),
161 	S_REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, TGRAN64, 0),
162 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, TGRAN16, 0),
163 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, BIGENDEL0, 0),
164 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, SNSMEM, 0),
165 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, BIGEND, 0),
166 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, PARANGE, 0),
167 	REG_FTR_END,
168 };
169 
170 static const struct reg_ftr_bits ftr_id_aa64mmfr1_el1[] = {
171 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR1_EL1, TIDCP1, 0),
172 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR1_EL1, AFP, 0),
173 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR1_EL1, HCX, 0),
174 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR1_EL1, ETS, 0),
175 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR1_EL1, TWED, 0),
176 	REG_FTR_BITS(FTR_HIGHER_SAFE, ID_AA64MMFR1_EL1, SpecSEI, 0),
177 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR1_EL1, PAN, 0),
178 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR1_EL1, LO, 0),
179 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR1_EL1, HPDS, 0),
180 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR1_EL1, HAFDBS, 0),
181 	REG_FTR_END,
182 };
183 
184 static const struct reg_ftr_bits ftr_id_aa64mmfr2_el1[] = {
185 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, E0PD, 0),
186 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, BBM, 0),
187 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, TTL, 0),
188 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, AT, 0),
189 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, ST, 0),
190 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, VARange, 0),
191 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, IESB, 0),
192 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, LSM, 0),
193 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, UAO, 0),
194 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, CnP, 0),
195 	REG_FTR_END,
196 };
197 
198 static const struct reg_ftr_bits ftr_id_aa64mmfr3_el1[] = {
199 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR3_EL1, S1POE, 0),
200 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR3_EL1, S1PIE, 0),
201 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR3_EL1, SCTLRX, 0),
202 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR3_EL1, TCRX, 0),
203 	REG_FTR_END,
204 };
205 
206 static const struct reg_ftr_bits ftr_id_aa64zfr0_el1[] = {
207 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, F64MM, 0),
208 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, F32MM, 0),
209 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, I8MM, 0),
210 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, SM4, 0),
211 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, SHA3, 0),
212 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, BF16, 0),
213 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, BitPerm, 0),
214 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, AES, 0),
215 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, SVEver, 0),
216 	REG_FTR_END,
217 };
218 
219 #define TEST_REG(id, table)			\
220 	{					\
221 		.reg = id,			\
222 		.ftr_bits = &((table)[0]),	\
223 	}
224 
225 static struct test_feature_reg test_regs[] = {
226 	TEST_REG(SYS_ID_AA64DFR0_EL1, ftr_id_aa64dfr0_el1),
227 	TEST_REG(SYS_ID_DFR0_EL1, ftr_id_dfr0_el1),
228 	TEST_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0_el1),
229 	TEST_REG(SYS_ID_AA64ISAR1_EL1, ftr_id_aa64isar1_el1),
230 	TEST_REG(SYS_ID_AA64ISAR2_EL1, ftr_id_aa64isar2_el1),
231 	TEST_REG(SYS_ID_AA64ISAR3_EL1, ftr_id_aa64isar3_el1),
232 	TEST_REG(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0_el1),
233 	TEST_REG(SYS_ID_AA64PFR1_EL1, ftr_id_aa64pfr1_el1),
234 	TEST_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0_el1),
235 	TEST_REG(SYS_ID_AA64MMFR1_EL1, ftr_id_aa64mmfr1_el1),
236 	TEST_REG(SYS_ID_AA64MMFR2_EL1, ftr_id_aa64mmfr2_el1),
237 	TEST_REG(SYS_ID_AA64MMFR3_EL1, ftr_id_aa64mmfr3_el1),
238 	TEST_REG(SYS_ID_AA64ZFR0_EL1, ftr_id_aa64zfr0_el1),
239 };
240 
241 #define GUEST_REG_SYNC(id) GUEST_SYNC_ARGS(0, id, read_sysreg_s(id), 0, 0);
242 
243 static void guest_code(void)
244 {
245 	GUEST_REG_SYNC(SYS_ID_AA64DFR0_EL1);
246 	GUEST_REG_SYNC(SYS_ID_DFR0_EL1);
247 	GUEST_REG_SYNC(SYS_ID_AA64ISAR0_EL1);
248 	GUEST_REG_SYNC(SYS_ID_AA64ISAR1_EL1);
249 	GUEST_REG_SYNC(SYS_ID_AA64ISAR2_EL1);
250 	GUEST_REG_SYNC(SYS_ID_AA64ISAR3_EL1);
251 	GUEST_REG_SYNC(SYS_ID_AA64PFR0_EL1);
252 	GUEST_REG_SYNC(SYS_ID_AA64PFR1_EL1);
253 	GUEST_REG_SYNC(SYS_ID_AA64MMFR0_EL1);
254 	GUEST_REG_SYNC(SYS_ID_AA64MMFR1_EL1);
255 	GUEST_REG_SYNC(SYS_ID_AA64MMFR2_EL1);
256 	GUEST_REG_SYNC(SYS_ID_AA64MMFR3_EL1);
257 	GUEST_REG_SYNC(SYS_ID_AA64ZFR0_EL1);
258 	GUEST_REG_SYNC(SYS_MPIDR_EL1);
259 	GUEST_REG_SYNC(SYS_CLIDR_EL1);
260 	GUEST_REG_SYNC(SYS_CTR_EL0);
261 	GUEST_REG_SYNC(SYS_MIDR_EL1);
262 	GUEST_REG_SYNC(SYS_REVIDR_EL1);
263 	GUEST_REG_SYNC(SYS_AIDR_EL1);
264 
265 	GUEST_DONE();
266 }
267 
268 /* Return a safe value to a given ftr_bits an ftr value */
269 uint64_t get_safe_value(const struct reg_ftr_bits *ftr_bits, uint64_t ftr)
270 {
271 	uint64_t ftr_max = ftr_bits->mask >> ftr_bits->shift;
272 
273 	TEST_ASSERT(ftr_max > 1, "This test doesn't support single bit features");
274 
275 	if (ftr_bits->sign == FTR_UNSIGNED) {
276 		switch (ftr_bits->type) {
277 		case FTR_EXACT:
278 			ftr = ftr_bits->safe_val;
279 			break;
280 		case FTR_LOWER_SAFE:
281 			if (ftr > ftr_bits->safe_val)
282 				ftr--;
283 			break;
284 		case FTR_HIGHER_SAFE:
285 			if (ftr < ftr_max)
286 				ftr++;
287 			break;
288 		case FTR_HIGHER_OR_ZERO_SAFE:
289 			if (ftr == ftr_max)
290 				ftr = 0;
291 			else if (ftr != 0)
292 				ftr++;
293 			break;
294 		default:
295 			break;
296 		}
297 	} else if (ftr != ftr_max) {
298 		switch (ftr_bits->type) {
299 		case FTR_EXACT:
300 			ftr = ftr_bits->safe_val;
301 			break;
302 		case FTR_LOWER_SAFE:
303 			if (ftr > ftr_bits->safe_val)
304 				ftr--;
305 			break;
306 		case FTR_HIGHER_SAFE:
307 			if (ftr < ftr_max - 1)
308 				ftr++;
309 			break;
310 		case FTR_HIGHER_OR_ZERO_SAFE:
311 			if (ftr != 0 && ftr != ftr_max - 1)
312 				ftr++;
313 			break;
314 		default:
315 			break;
316 		}
317 	}
318 
319 	return ftr;
320 }
321 
322 /* Return an invalid value to a given ftr_bits an ftr value */
323 uint64_t get_invalid_value(const struct reg_ftr_bits *ftr_bits, uint64_t ftr)
324 {
325 	uint64_t ftr_max = ftr_bits->mask >> ftr_bits->shift;
326 
327 	TEST_ASSERT(ftr_max > 1, "This test doesn't support single bit features");
328 
329 	if (ftr_bits->sign == FTR_UNSIGNED) {
330 		switch (ftr_bits->type) {
331 		case FTR_EXACT:
332 			ftr = max((uint64_t)ftr_bits->safe_val + 1, ftr + 1);
333 			break;
334 		case FTR_LOWER_SAFE:
335 			ftr++;
336 			break;
337 		case FTR_HIGHER_SAFE:
338 			ftr--;
339 			break;
340 		case FTR_HIGHER_OR_ZERO_SAFE:
341 			if (ftr == 0)
342 				ftr = ftr_max;
343 			else
344 				ftr--;
345 			break;
346 		default:
347 			break;
348 		}
349 	} else if (ftr != ftr_max) {
350 		switch (ftr_bits->type) {
351 		case FTR_EXACT:
352 			ftr = max((uint64_t)ftr_bits->safe_val + 1, ftr + 1);
353 			break;
354 		case FTR_LOWER_SAFE:
355 			ftr++;
356 			break;
357 		case FTR_HIGHER_SAFE:
358 			ftr--;
359 			break;
360 		case FTR_HIGHER_OR_ZERO_SAFE:
361 			if (ftr == 0)
362 				ftr = ftr_max - 1;
363 			else
364 				ftr--;
365 			break;
366 		default:
367 			break;
368 		}
369 	} else {
370 		ftr = 0;
371 	}
372 
373 	return ftr;
374 }
375 
376 static uint64_t test_reg_set_success(struct kvm_vcpu *vcpu, uint64_t reg,
377 				     const struct reg_ftr_bits *ftr_bits)
378 {
379 	uint8_t shift = ftr_bits->shift;
380 	uint64_t mask = ftr_bits->mask;
381 	uint64_t val, new_val, ftr;
382 
383 	val = vcpu_get_reg(vcpu, reg);
384 	ftr = (val & mask) >> shift;
385 
386 	ftr = get_safe_value(ftr_bits, ftr);
387 
388 	ftr <<= shift;
389 	val &= ~mask;
390 	val |= ftr;
391 
392 	vcpu_set_reg(vcpu, reg, val);
393 	new_val = vcpu_get_reg(vcpu, reg);
394 	TEST_ASSERT_EQ(new_val, val);
395 
396 	return new_val;
397 }
398 
399 static void test_reg_set_fail(struct kvm_vcpu *vcpu, uint64_t reg,
400 			      const struct reg_ftr_bits *ftr_bits)
401 {
402 	uint8_t shift = ftr_bits->shift;
403 	uint64_t mask = ftr_bits->mask;
404 	uint64_t val, old_val, ftr;
405 	int r;
406 
407 	val = vcpu_get_reg(vcpu, reg);
408 	ftr = (val & mask) >> shift;
409 
410 	ftr = get_invalid_value(ftr_bits, ftr);
411 
412 	old_val = val;
413 	ftr <<= shift;
414 	val &= ~mask;
415 	val |= ftr;
416 
417 	r = __vcpu_set_reg(vcpu, reg, val);
418 	TEST_ASSERT(r < 0 && errno == EINVAL,
419 		    "Unexpected KVM_SET_ONE_REG error: r=%d, errno=%d", r, errno);
420 
421 	val = vcpu_get_reg(vcpu, reg);
422 	TEST_ASSERT_EQ(val, old_val);
423 }
424 
425 static uint64_t test_reg_vals[KVM_ARM_FEATURE_ID_RANGE_SIZE];
426 
427 #define encoding_to_range_idx(encoding)							\
428 	KVM_ARM_FEATURE_ID_RANGE_IDX(sys_reg_Op0(encoding), sys_reg_Op1(encoding),	\
429 				     sys_reg_CRn(encoding), sys_reg_CRm(encoding),	\
430 				     sys_reg_Op2(encoding))
431 
432 
433 static void test_vm_ftr_id_regs(struct kvm_vcpu *vcpu, bool aarch64_only)
434 {
435 	uint64_t masks[KVM_ARM_FEATURE_ID_RANGE_SIZE];
436 	struct reg_mask_range range = {
437 		.addr = (__u64)masks,
438 	};
439 	int ret;
440 
441 	/* KVM should return error when reserved field is not zero */
442 	range.reserved[0] = 1;
443 	ret = __vm_ioctl(vcpu->vm, KVM_ARM_GET_REG_WRITABLE_MASKS, &range);
444 	TEST_ASSERT(ret, "KVM doesn't check invalid parameters.");
445 
446 	/* Get writable masks for feature ID registers */
447 	memset(range.reserved, 0, sizeof(range.reserved));
448 	vm_ioctl(vcpu->vm, KVM_ARM_GET_REG_WRITABLE_MASKS, &range);
449 
450 	for (int i = 0; i < ARRAY_SIZE(test_regs); i++) {
451 		const struct reg_ftr_bits *ftr_bits = test_regs[i].ftr_bits;
452 		uint32_t reg_id = test_regs[i].reg;
453 		uint64_t reg = KVM_ARM64_SYS_REG(reg_id);
454 		int idx;
455 
456 		/* Get the index to masks array for the idreg */
457 		idx = encoding_to_range_idx(reg_id);
458 
459 		for (int j = 0;  ftr_bits[j].type != FTR_END; j++) {
460 			/* Skip aarch32 reg on aarch64 only system, since they are RAZ/WI. */
461 			if (aarch64_only && sys_reg_CRm(reg_id) < 4) {
462 				ksft_test_result_skip("%s on AARCH64 only system\n",
463 						      ftr_bits[j].name);
464 				continue;
465 			}
466 
467 			/* Make sure the feature field is writable */
468 			TEST_ASSERT_EQ(masks[idx] & ftr_bits[j].mask, ftr_bits[j].mask);
469 
470 			test_reg_set_fail(vcpu, reg, &ftr_bits[j]);
471 
472 			test_reg_vals[idx] = test_reg_set_success(vcpu, reg,
473 								  &ftr_bits[j]);
474 
475 			ksft_test_result_pass("%s\n", ftr_bits[j].name);
476 		}
477 	}
478 }
479 
480 #define MPAM_IDREG_TEST	6
481 static void test_user_set_mpam_reg(struct kvm_vcpu *vcpu)
482 {
483 	uint64_t masks[KVM_ARM_FEATURE_ID_RANGE_SIZE];
484 	struct reg_mask_range range = {
485 		.addr = (__u64)masks,
486 	};
487 	uint64_t val;
488 	int idx, err;
489 
490 	/*
491 	 * If ID_AA64PFR0.MPAM is _not_ officially modifiable and is zero,
492 	 * check that if it can be set to 1, (i.e. it is supported by the
493 	 * hardware), that it can't be set to other values.
494 	 */
495 
496 	/* Get writable masks for feature ID registers */
497 	memset(range.reserved, 0, sizeof(range.reserved));
498 	vm_ioctl(vcpu->vm, KVM_ARM_GET_REG_WRITABLE_MASKS, &range);
499 
500 	/* Writeable? Nothing to test! */
501 	idx = encoding_to_range_idx(SYS_ID_AA64PFR0_EL1);
502 	if ((masks[idx] & ID_AA64PFR0_EL1_MPAM_MASK) == ID_AA64PFR0_EL1_MPAM_MASK) {
503 		ksft_test_result_skip("ID_AA64PFR0_EL1.MPAM is officially writable, nothing to test\n");
504 		return;
505 	}
506 
507 	/* Get the id register value */
508 	val = vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR0_EL1));
509 
510 	/* Try to set MPAM=0. This should always be possible. */
511 	val &= ~ID_AA64PFR0_EL1_MPAM_MASK;
512 	val |= FIELD_PREP(ID_AA64PFR0_EL1_MPAM_MASK, 0);
513 	err = __vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR0_EL1), val);
514 	if (err)
515 		ksft_test_result_fail("ID_AA64PFR0_EL1.MPAM=0 was not accepted\n");
516 	else
517 		ksft_test_result_pass("ID_AA64PFR0_EL1.MPAM=0 worked\n");
518 
519 	/* Try to set MPAM=1 */
520 	val &= ~ID_AA64PFR0_EL1_MPAM_MASK;
521 	val |= FIELD_PREP(ID_AA64PFR0_EL1_MPAM_MASK, 1);
522 	err = __vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR0_EL1), val);
523 	if (err)
524 		ksft_test_result_skip("ID_AA64PFR0_EL1.MPAM is not writable, nothing to test\n");
525 	else
526 		ksft_test_result_pass("ID_AA64PFR0_EL1.MPAM=1 was writable\n");
527 
528 	/* Try to set MPAM=2 */
529 	val &= ~ID_AA64PFR0_EL1_MPAM_MASK;
530 	val |= FIELD_PREP(ID_AA64PFR0_EL1_MPAM_MASK, 2);
531 	err = __vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR0_EL1), val);
532 	if (err)
533 		ksft_test_result_pass("ID_AA64PFR0_EL1.MPAM not arbitrarily modifiable\n");
534 	else
535 		ksft_test_result_fail("ID_AA64PFR0_EL1.MPAM value should not be ignored\n");
536 
537 	/* And again for ID_AA64PFR1_EL1.MPAM_frac */
538 	idx = encoding_to_range_idx(SYS_ID_AA64PFR1_EL1);
539 	if ((masks[idx] & ID_AA64PFR1_EL1_MPAM_frac_MASK) == ID_AA64PFR1_EL1_MPAM_frac_MASK) {
540 		ksft_test_result_skip("ID_AA64PFR1_EL1.MPAM_frac is officially writable, nothing to test\n");
541 		return;
542 	}
543 
544 	/* Get the id register value */
545 	val = vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR1_EL1));
546 
547 	/* Try to set MPAM_frac=0. This should always be possible. */
548 	val &= ~ID_AA64PFR1_EL1_MPAM_frac_MASK;
549 	val |= FIELD_PREP(ID_AA64PFR1_EL1_MPAM_frac_MASK, 0);
550 	err = __vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR1_EL1), val);
551 	if (err)
552 		ksft_test_result_fail("ID_AA64PFR0_EL1.MPAM_frac=0 was not accepted\n");
553 	else
554 		ksft_test_result_pass("ID_AA64PFR0_EL1.MPAM_frac=0 worked\n");
555 
556 	/* Try to set MPAM_frac=1 */
557 	val &= ~ID_AA64PFR1_EL1_MPAM_frac_MASK;
558 	val |= FIELD_PREP(ID_AA64PFR1_EL1_MPAM_frac_MASK, 1);
559 	err = __vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR1_EL1), val);
560 	if (err)
561 		ksft_test_result_skip("ID_AA64PFR1_EL1.MPAM_frac is not writable, nothing to test\n");
562 	else
563 		ksft_test_result_pass("ID_AA64PFR0_EL1.MPAM_frac=1 was writable\n");
564 
565 	/* Try to set MPAM_frac=2 */
566 	val &= ~ID_AA64PFR1_EL1_MPAM_frac_MASK;
567 	val |= FIELD_PREP(ID_AA64PFR1_EL1_MPAM_frac_MASK, 2);
568 	err = __vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR1_EL1), val);
569 	if (err)
570 		ksft_test_result_pass("ID_AA64PFR1_EL1.MPAM_frac not arbitrarily modifiable\n");
571 	else
572 		ksft_test_result_fail("ID_AA64PFR1_EL1.MPAM_frac value should not be ignored\n");
573 }
574 
575 #define MTE_IDREG_TEST 1
576 static void test_user_set_mte_reg(struct kvm_vcpu *vcpu)
577 {
578 	uint64_t masks[KVM_ARM_FEATURE_ID_RANGE_SIZE];
579 	struct reg_mask_range range = {
580 		.addr = (__u64)masks,
581 	};
582 	uint64_t val;
583 	uint64_t mte;
584 	uint64_t mte_frac;
585 	int idx, err;
586 
587 	val = vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR1_EL1));
588 	mte = FIELD_GET(ID_AA64PFR1_EL1_MTE, val);
589 	if (!mte) {
590 		ksft_test_result_skip("MTE capability not supported, nothing to test\n");
591 		return;
592 	}
593 
594 	/* Get writable masks for feature ID registers */
595 	memset(range.reserved, 0, sizeof(range.reserved));
596 	vm_ioctl(vcpu->vm, KVM_ARM_GET_REG_WRITABLE_MASKS, &range);
597 
598 	idx = encoding_to_range_idx(SYS_ID_AA64PFR1_EL1);
599 	if ((masks[idx] & ID_AA64PFR1_EL1_MTE_frac_MASK) == ID_AA64PFR1_EL1_MTE_frac_MASK) {
600 		ksft_test_result_skip("ID_AA64PFR1_EL1.MTE_frac is officially writable, nothing to test\n");
601 		return;
602 	}
603 
604 	/*
605 	 * When MTE is supported but MTE_ASYMM is not (ID_AA64PFR1_EL1.MTE == 2)
606 	 * ID_AA64PFR1_EL1.MTE_frac == 0xF indicates MTE_ASYNC is unsupported
607 	 * and MTE_frac == 0 indicates it is supported.
608 	 *
609 	 * As MTE_frac was previously unconditionally read as 0, check
610 	 * that the set to 0 succeeds but does not change MTE_frac
611 	 * from unsupported (0xF) to supported (0).
612 	 *
613 	 */
614 	mte_frac = FIELD_GET(ID_AA64PFR1_EL1_MTE_frac, val);
615 	if (mte != ID_AA64PFR1_EL1_MTE_MTE2 ||
616 	    mte_frac != ID_AA64PFR1_EL1_MTE_frac_NI) {
617 		ksft_test_result_skip("MTE_ASYNC or MTE_ASYMM are supported, nothing to test\n");
618 		return;
619 	}
620 
621 	/* Try to set MTE_frac=0. */
622 	val &= ~ID_AA64PFR1_EL1_MTE_frac_MASK;
623 	val |= FIELD_PREP(ID_AA64PFR1_EL1_MTE_frac_MASK, 0);
624 	err = __vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR1_EL1), val);
625 	if (err) {
626 		ksft_test_result_fail("ID_AA64PFR1_EL1.MTE_frac=0 was not accepted\n");
627 		return;
628 	}
629 
630 	val = vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR1_EL1));
631 	mte_frac = FIELD_GET(ID_AA64PFR1_EL1_MTE_frac, val);
632 	if (mte_frac == ID_AA64PFR1_EL1_MTE_frac_NI)
633 		ksft_test_result_pass("ID_AA64PFR1_EL1.MTE_frac=0 accepted and still 0xF\n");
634 	else
635 		ksft_test_result_pass("ID_AA64PFR1_EL1.MTE_frac no longer 0xF\n");
636 }
637 
638 static void test_guest_reg_read(struct kvm_vcpu *vcpu)
639 {
640 	bool done = false;
641 	struct ucall uc;
642 
643 	while (!done) {
644 		vcpu_run(vcpu);
645 
646 		switch (get_ucall(vcpu, &uc)) {
647 		case UCALL_ABORT:
648 			REPORT_GUEST_ASSERT(uc);
649 			break;
650 		case UCALL_SYNC:
651 			/* Make sure the written values are seen by guest */
652 			TEST_ASSERT_EQ(test_reg_vals[encoding_to_range_idx(uc.args[2])],
653 				       uc.args[3]);
654 			break;
655 		case UCALL_DONE:
656 			done = true;
657 			break;
658 		default:
659 			TEST_FAIL("Unexpected ucall: %lu", uc.cmd);
660 		}
661 	}
662 }
663 
664 /* Politely lifted from arch/arm64/include/asm/cache.h */
665 /* Ctypen, bits[3(n - 1) + 2 : 3(n - 1)], for n = 1 to 7 */
666 #define CLIDR_CTYPE_SHIFT(level)	(3 * (level - 1))
667 #define CLIDR_CTYPE_MASK(level)		(7 << CLIDR_CTYPE_SHIFT(level))
668 #define CLIDR_CTYPE(clidr, level)	\
669 	(((clidr) & CLIDR_CTYPE_MASK(level)) >> CLIDR_CTYPE_SHIFT(level))
670 
671 static void test_clidr(struct kvm_vcpu *vcpu)
672 {
673 	uint64_t clidr;
674 	int level;
675 
676 	clidr = vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_CLIDR_EL1));
677 
678 	/* find the first empty level in the cache hierarchy */
679 	for (level = 1; level <= 7; level++) {
680 		if (!CLIDR_CTYPE(clidr, level))
681 			break;
682 	}
683 
684 	/*
685 	 * If you have a mind-boggling 7 levels of cache, congratulations, you
686 	 * get to fix this.
687 	 */
688 	TEST_ASSERT(level <= 7, "can't find an empty level in cache hierarchy");
689 
690 	/* stick in a unified cache level */
691 	clidr |= BIT(2) << CLIDR_CTYPE_SHIFT(level);
692 
693 	vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_CLIDR_EL1), clidr);
694 	test_reg_vals[encoding_to_range_idx(SYS_CLIDR_EL1)] = clidr;
695 }
696 
697 static void test_ctr(struct kvm_vcpu *vcpu)
698 {
699 	u64 ctr;
700 
701 	ctr = vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_CTR_EL0));
702 	ctr &= ~CTR_EL0_DIC_MASK;
703 	if (ctr & CTR_EL0_IminLine_MASK)
704 		ctr--;
705 
706 	vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_CTR_EL0), ctr);
707 	test_reg_vals[encoding_to_range_idx(SYS_CTR_EL0)] = ctr;
708 }
709 
710 static void test_id_reg(struct kvm_vcpu *vcpu, u32 id)
711 {
712 	u64 val;
713 
714 	val = vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(id));
715 	val++;
716 	vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(id), val);
717 	test_reg_vals[encoding_to_range_idx(id)] = val;
718 }
719 
720 static void test_vcpu_ftr_id_regs(struct kvm_vcpu *vcpu)
721 {
722 	test_clidr(vcpu);
723 	test_ctr(vcpu);
724 
725 	test_id_reg(vcpu, SYS_MPIDR_EL1);
726 	ksft_test_result_pass("%s\n", __func__);
727 }
728 
729 static void test_vcpu_non_ftr_id_regs(struct kvm_vcpu *vcpu)
730 {
731 	test_id_reg(vcpu, SYS_MIDR_EL1);
732 	test_id_reg(vcpu, SYS_REVIDR_EL1);
733 	test_id_reg(vcpu, SYS_AIDR_EL1);
734 
735 	ksft_test_result_pass("%s\n", __func__);
736 }
737 
738 static void test_assert_id_reg_unchanged(struct kvm_vcpu *vcpu, uint32_t encoding)
739 {
740 	size_t idx = encoding_to_range_idx(encoding);
741 	uint64_t observed;
742 
743 	observed = vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(encoding));
744 	TEST_ASSERT_EQ(test_reg_vals[idx], observed);
745 }
746 
747 static void test_reset_preserves_id_regs(struct kvm_vcpu *vcpu)
748 {
749 	/*
750 	 * Calls KVM_ARM_VCPU_INIT behind the scenes, which will do an
751 	 * architectural reset of the vCPU.
752 	 */
753 	aarch64_vcpu_setup(vcpu, NULL);
754 
755 	for (int i = 0; i < ARRAY_SIZE(test_regs); i++)
756 		test_assert_id_reg_unchanged(vcpu, test_regs[i].reg);
757 
758 	test_assert_id_reg_unchanged(vcpu, SYS_MPIDR_EL1);
759 	test_assert_id_reg_unchanged(vcpu, SYS_CLIDR_EL1);
760 	test_assert_id_reg_unchanged(vcpu, SYS_CTR_EL0);
761 	test_assert_id_reg_unchanged(vcpu, SYS_MIDR_EL1);
762 	test_assert_id_reg_unchanged(vcpu, SYS_REVIDR_EL1);
763 	test_assert_id_reg_unchanged(vcpu, SYS_AIDR_EL1);
764 
765 	ksft_test_result_pass("%s\n", __func__);
766 }
767 
768 int main(void)
769 {
770 	struct kvm_vcpu *vcpu;
771 	struct kvm_vm *vm;
772 	bool aarch64_only;
773 	uint64_t val, el0;
774 	int test_cnt, i, j;
775 
776 	TEST_REQUIRE(kvm_has_cap(KVM_CAP_ARM_SUPPORTED_REG_MASK_RANGES));
777 	TEST_REQUIRE(kvm_has_cap(KVM_CAP_ARM_WRITABLE_IMP_ID_REGS));
778 
779 	test_wants_mte();
780 
781 	vm = vm_create(1);
782 	vm_enable_cap(vm, KVM_CAP_ARM_WRITABLE_IMP_ID_REGS, 0);
783 	vcpu = vm_vcpu_add(vm, 0, guest_code);
784 	kvm_arch_vm_finalize_vcpus(vm);
785 
786 	/* Check for AARCH64 only system */
787 	val = vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR0_EL1));
788 	el0 = FIELD_GET(ID_AA64PFR0_EL1_EL0, val);
789 	aarch64_only = (el0 == ID_AA64PFR0_EL1_EL0_IMP);
790 
791 	ksft_print_header();
792 
793 	test_cnt = 3 + MPAM_IDREG_TEST + MTE_IDREG_TEST;
794 	for (i = 0; i < ARRAY_SIZE(test_regs); i++)
795 		for (j = 0; test_regs[i].ftr_bits[j].type != FTR_END; j++)
796 			test_cnt++;
797 
798 	ksft_set_plan(test_cnt);
799 
800 	test_vm_ftr_id_regs(vcpu, aarch64_only);
801 	test_vcpu_ftr_id_regs(vcpu);
802 	test_vcpu_non_ftr_id_regs(vcpu);
803 	test_user_set_mpam_reg(vcpu);
804 	test_user_set_mte_reg(vcpu);
805 
806 	test_guest_reg_read(vcpu);
807 
808 	test_reset_preserves_id_regs(vcpu);
809 
810 	kvm_vm_free(vm);
811 
812 	ksft_finished();
813 }
814