xref: /linux/tools/testing/selftests/kvm/aarch64/set_id_regs.c (revision a634dda26186cf9a51567020fcce52bcba5e1e59)
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_aa64pfr0_el1[] = {
127 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, CSV3, 0),
128 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, CSV2, 0),
129 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, DIT, 0),
130 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, SEL2, 0),
131 	REG_FTR_BITS(FTR_EXACT, ID_AA64PFR0_EL1, GIC, 0),
132 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, EL3, 0),
133 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, EL2, 0),
134 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, EL1, 0),
135 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR0_EL1, EL0, 0),
136 	REG_FTR_END,
137 };
138 
139 static const struct reg_ftr_bits ftr_id_aa64pfr1_el1[] = {
140 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR1_EL1, CSV2_frac, 0),
141 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR1_EL1, SSBS, ID_AA64PFR1_EL1_SSBS_NI),
142 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64PFR1_EL1, BT, 0),
143 	REG_FTR_END,
144 };
145 
146 static const struct reg_ftr_bits ftr_id_aa64mmfr0_el1[] = {
147 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, ECV, 0),
148 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, EXS, 0),
149 	S_REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, TGRAN4, 0),
150 	S_REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, TGRAN64, 0),
151 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, TGRAN16, 0),
152 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, BIGENDEL0, 0),
153 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, SNSMEM, 0),
154 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, BIGEND, 0),
155 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR0_EL1, PARANGE, 0),
156 	REG_FTR_END,
157 };
158 
159 static const struct reg_ftr_bits ftr_id_aa64mmfr1_el1[] = {
160 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR1_EL1, TIDCP1, 0),
161 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR1_EL1, AFP, 0),
162 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR1_EL1, ETS, 0),
163 	REG_FTR_BITS(FTR_HIGHER_SAFE, ID_AA64MMFR1_EL1, SpecSEI, 0),
164 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR1_EL1, PAN, 0),
165 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR1_EL1, LO, 0),
166 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR1_EL1, HPDS, 0),
167 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR1_EL1, HAFDBS, 0),
168 	REG_FTR_END,
169 };
170 
171 static const struct reg_ftr_bits ftr_id_aa64mmfr2_el1[] = {
172 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, E0PD, 0),
173 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, BBM, 0),
174 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, TTL, 0),
175 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, AT, 0),
176 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, ST, 0),
177 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, VARange, 0),
178 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, IESB, 0),
179 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, LSM, 0),
180 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, UAO, 0),
181 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64MMFR2_EL1, CnP, 0),
182 	REG_FTR_END,
183 };
184 
185 static const struct reg_ftr_bits ftr_id_aa64zfr0_el1[] = {
186 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, F64MM, 0),
187 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, F32MM, 0),
188 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, I8MM, 0),
189 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, SM4, 0),
190 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, SHA3, 0),
191 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, BF16, 0),
192 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, BitPerm, 0),
193 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, AES, 0),
194 	REG_FTR_BITS(FTR_LOWER_SAFE, ID_AA64ZFR0_EL1, SVEver, 0),
195 	REG_FTR_END,
196 };
197 
198 #define TEST_REG(id, table)			\
199 	{					\
200 		.reg = id,			\
201 		.ftr_bits = &((table)[0]),	\
202 	}
203 
204 static struct test_feature_reg test_regs[] = {
205 	TEST_REG(SYS_ID_AA64DFR0_EL1, ftr_id_aa64dfr0_el1),
206 	TEST_REG(SYS_ID_DFR0_EL1, ftr_id_dfr0_el1),
207 	TEST_REG(SYS_ID_AA64ISAR0_EL1, ftr_id_aa64isar0_el1),
208 	TEST_REG(SYS_ID_AA64ISAR1_EL1, ftr_id_aa64isar1_el1),
209 	TEST_REG(SYS_ID_AA64ISAR2_EL1, ftr_id_aa64isar2_el1),
210 	TEST_REG(SYS_ID_AA64PFR0_EL1, ftr_id_aa64pfr0_el1),
211 	TEST_REG(SYS_ID_AA64PFR1_EL1, ftr_id_aa64pfr1_el1),
212 	TEST_REG(SYS_ID_AA64MMFR0_EL1, ftr_id_aa64mmfr0_el1),
213 	TEST_REG(SYS_ID_AA64MMFR1_EL1, ftr_id_aa64mmfr1_el1),
214 	TEST_REG(SYS_ID_AA64MMFR2_EL1, ftr_id_aa64mmfr2_el1),
215 	TEST_REG(SYS_ID_AA64ZFR0_EL1, ftr_id_aa64zfr0_el1),
216 };
217 
218 #define GUEST_REG_SYNC(id) GUEST_SYNC_ARGS(0, id, read_sysreg_s(id), 0, 0);
219 
220 static void guest_code(void)
221 {
222 	GUEST_REG_SYNC(SYS_ID_AA64DFR0_EL1);
223 	GUEST_REG_SYNC(SYS_ID_DFR0_EL1);
224 	GUEST_REG_SYNC(SYS_ID_AA64ISAR0_EL1);
225 	GUEST_REG_SYNC(SYS_ID_AA64ISAR1_EL1);
226 	GUEST_REG_SYNC(SYS_ID_AA64ISAR2_EL1);
227 	GUEST_REG_SYNC(SYS_ID_AA64PFR0_EL1);
228 	GUEST_REG_SYNC(SYS_ID_AA64MMFR0_EL1);
229 	GUEST_REG_SYNC(SYS_ID_AA64MMFR1_EL1);
230 	GUEST_REG_SYNC(SYS_ID_AA64MMFR2_EL1);
231 	GUEST_REG_SYNC(SYS_ID_AA64ZFR0_EL1);
232 	GUEST_REG_SYNC(SYS_CTR_EL0);
233 
234 	GUEST_DONE();
235 }
236 
237 /* Return a safe value to a given ftr_bits an ftr value */
238 uint64_t get_safe_value(const struct reg_ftr_bits *ftr_bits, uint64_t ftr)
239 {
240 	uint64_t ftr_max = GENMASK_ULL(ARM64_FEATURE_FIELD_BITS - 1, 0);
241 
242 	if (ftr_bits->sign == FTR_UNSIGNED) {
243 		switch (ftr_bits->type) {
244 		case FTR_EXACT:
245 			ftr = ftr_bits->safe_val;
246 			break;
247 		case FTR_LOWER_SAFE:
248 			if (ftr > ftr_bits->safe_val)
249 				ftr--;
250 			break;
251 		case FTR_HIGHER_SAFE:
252 			if (ftr < ftr_max)
253 				ftr++;
254 			break;
255 		case FTR_HIGHER_OR_ZERO_SAFE:
256 			if (ftr == ftr_max)
257 				ftr = 0;
258 			else if (ftr != 0)
259 				ftr++;
260 			break;
261 		default:
262 			break;
263 		}
264 	} else if (ftr != ftr_max) {
265 		switch (ftr_bits->type) {
266 		case FTR_EXACT:
267 			ftr = ftr_bits->safe_val;
268 			break;
269 		case FTR_LOWER_SAFE:
270 			if (ftr > ftr_bits->safe_val)
271 				ftr--;
272 			break;
273 		case FTR_HIGHER_SAFE:
274 			if (ftr < ftr_max - 1)
275 				ftr++;
276 			break;
277 		case FTR_HIGHER_OR_ZERO_SAFE:
278 			if (ftr != 0 && ftr != ftr_max - 1)
279 				ftr++;
280 			break;
281 		default:
282 			break;
283 		}
284 	}
285 
286 	return ftr;
287 }
288 
289 /* Return an invalid value to a given ftr_bits an ftr value */
290 uint64_t get_invalid_value(const struct reg_ftr_bits *ftr_bits, uint64_t ftr)
291 {
292 	uint64_t ftr_max = GENMASK_ULL(ARM64_FEATURE_FIELD_BITS - 1, 0);
293 
294 	if (ftr_bits->sign == FTR_UNSIGNED) {
295 		switch (ftr_bits->type) {
296 		case FTR_EXACT:
297 			ftr = max((uint64_t)ftr_bits->safe_val + 1, ftr + 1);
298 			break;
299 		case FTR_LOWER_SAFE:
300 			ftr++;
301 			break;
302 		case FTR_HIGHER_SAFE:
303 			ftr--;
304 			break;
305 		case FTR_HIGHER_OR_ZERO_SAFE:
306 			if (ftr == 0)
307 				ftr = ftr_max;
308 			else
309 				ftr--;
310 			break;
311 		default:
312 			break;
313 		}
314 	} else if (ftr != ftr_max) {
315 		switch (ftr_bits->type) {
316 		case FTR_EXACT:
317 			ftr = max((uint64_t)ftr_bits->safe_val + 1, ftr + 1);
318 			break;
319 		case FTR_LOWER_SAFE:
320 			ftr++;
321 			break;
322 		case FTR_HIGHER_SAFE:
323 			ftr--;
324 			break;
325 		case FTR_HIGHER_OR_ZERO_SAFE:
326 			if (ftr == 0)
327 				ftr = ftr_max - 1;
328 			else
329 				ftr--;
330 			break;
331 		default:
332 			break;
333 		}
334 	} else {
335 		ftr = 0;
336 	}
337 
338 	return ftr;
339 }
340 
341 static uint64_t test_reg_set_success(struct kvm_vcpu *vcpu, uint64_t reg,
342 				     const struct reg_ftr_bits *ftr_bits)
343 {
344 	uint8_t shift = ftr_bits->shift;
345 	uint64_t mask = ftr_bits->mask;
346 	uint64_t val, new_val, ftr;
347 
348 	vcpu_get_reg(vcpu, reg, &val);
349 	ftr = (val & mask) >> shift;
350 
351 	ftr = get_safe_value(ftr_bits, ftr);
352 
353 	ftr <<= shift;
354 	val &= ~mask;
355 	val |= ftr;
356 
357 	vcpu_set_reg(vcpu, reg, val);
358 	vcpu_get_reg(vcpu, reg, &new_val);
359 	TEST_ASSERT_EQ(new_val, val);
360 
361 	return new_val;
362 }
363 
364 static void test_reg_set_fail(struct kvm_vcpu *vcpu, uint64_t reg,
365 			      const struct reg_ftr_bits *ftr_bits)
366 {
367 	uint8_t shift = ftr_bits->shift;
368 	uint64_t mask = ftr_bits->mask;
369 	uint64_t val, old_val, ftr;
370 	int r;
371 
372 	vcpu_get_reg(vcpu, reg, &val);
373 	ftr = (val & mask) >> shift;
374 
375 	ftr = get_invalid_value(ftr_bits, ftr);
376 
377 	old_val = val;
378 	ftr <<= shift;
379 	val &= ~mask;
380 	val |= ftr;
381 
382 	r = __vcpu_set_reg(vcpu, reg, val);
383 	TEST_ASSERT(r < 0 && errno == EINVAL,
384 		    "Unexpected KVM_SET_ONE_REG error: r=%d, errno=%d", r, errno);
385 
386 	vcpu_get_reg(vcpu, reg, &val);
387 	TEST_ASSERT_EQ(val, old_val);
388 }
389 
390 static uint64_t test_reg_vals[KVM_ARM_FEATURE_ID_RANGE_SIZE];
391 
392 #define encoding_to_range_idx(encoding)							\
393 	KVM_ARM_FEATURE_ID_RANGE_IDX(sys_reg_Op0(encoding), sys_reg_Op1(encoding),	\
394 				     sys_reg_CRn(encoding), sys_reg_CRm(encoding),	\
395 				     sys_reg_Op2(encoding))
396 
397 
398 static void test_vm_ftr_id_regs(struct kvm_vcpu *vcpu, bool aarch64_only)
399 {
400 	uint64_t masks[KVM_ARM_FEATURE_ID_RANGE_SIZE];
401 	struct reg_mask_range range = {
402 		.addr = (__u64)masks,
403 	};
404 	int ret;
405 
406 	/* KVM should return error when reserved field is not zero */
407 	range.reserved[0] = 1;
408 	ret = __vm_ioctl(vcpu->vm, KVM_ARM_GET_REG_WRITABLE_MASKS, &range);
409 	TEST_ASSERT(ret, "KVM doesn't check invalid parameters.");
410 
411 	/* Get writable masks for feature ID registers */
412 	memset(range.reserved, 0, sizeof(range.reserved));
413 	vm_ioctl(vcpu->vm, KVM_ARM_GET_REG_WRITABLE_MASKS, &range);
414 
415 	for (int i = 0; i < ARRAY_SIZE(test_regs); i++) {
416 		const struct reg_ftr_bits *ftr_bits = test_regs[i].ftr_bits;
417 		uint32_t reg_id = test_regs[i].reg;
418 		uint64_t reg = KVM_ARM64_SYS_REG(reg_id);
419 		int idx;
420 
421 		/* Get the index to masks array for the idreg */
422 		idx = encoding_to_range_idx(reg_id);
423 
424 		for (int j = 0;  ftr_bits[j].type != FTR_END; j++) {
425 			/* Skip aarch32 reg on aarch64 only system, since they are RAZ/WI. */
426 			if (aarch64_only && sys_reg_CRm(reg_id) < 4) {
427 				ksft_test_result_skip("%s on AARCH64 only system\n",
428 						      ftr_bits[j].name);
429 				continue;
430 			}
431 
432 			/* Make sure the feature field is writable */
433 			TEST_ASSERT_EQ(masks[idx] & ftr_bits[j].mask, ftr_bits[j].mask);
434 
435 			test_reg_set_fail(vcpu, reg, &ftr_bits[j]);
436 
437 			test_reg_vals[idx] = test_reg_set_success(vcpu, reg,
438 								  &ftr_bits[j]);
439 
440 			ksft_test_result_pass("%s\n", ftr_bits[j].name);
441 		}
442 	}
443 }
444 
445 #define MPAM_IDREG_TEST	6
446 static void test_user_set_mpam_reg(struct kvm_vcpu *vcpu)
447 {
448 	uint64_t masks[KVM_ARM_FEATURE_ID_RANGE_SIZE];
449 	struct reg_mask_range range = {
450 		.addr = (__u64)masks,
451 	};
452 	uint64_t val;
453 	int idx, err;
454 
455 	/*
456 	 * If ID_AA64PFR0.MPAM is _not_ officially modifiable and is zero,
457 	 * check that if it can be set to 1, (i.e. it is supported by the
458 	 * hardware), that it can't be set to other values.
459 	 */
460 
461 	/* Get writable masks for feature ID registers */
462 	memset(range.reserved, 0, sizeof(range.reserved));
463 	vm_ioctl(vcpu->vm, KVM_ARM_GET_REG_WRITABLE_MASKS, &range);
464 
465 	/* Writeable? Nothing to test! */
466 	idx = encoding_to_range_idx(SYS_ID_AA64PFR0_EL1);
467 	if ((masks[idx] & ID_AA64PFR0_EL1_MPAM_MASK) == ID_AA64PFR0_EL1_MPAM_MASK) {
468 		ksft_test_result_skip("ID_AA64PFR0_EL1.MPAM is officially writable, nothing to test\n");
469 		return;
470 	}
471 
472 	/* Get the id register value */
473 	vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR0_EL1), &val);
474 
475 	/* Try to set MPAM=0. This should always be possible. */
476 	val &= ~ID_AA64PFR0_EL1_MPAM_MASK;
477 	val |= FIELD_PREP(ID_AA64PFR0_EL1_MPAM_MASK, 0);
478 	err = __vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR0_EL1), val);
479 	if (err)
480 		ksft_test_result_fail("ID_AA64PFR0_EL1.MPAM=0 was not accepted\n");
481 	else
482 		ksft_test_result_pass("ID_AA64PFR0_EL1.MPAM=0 worked\n");
483 
484 	/* Try to set MPAM=1 */
485 	val &= ~ID_AA64PFR0_EL1_MPAM_MASK;
486 	val |= FIELD_PREP(ID_AA64PFR0_EL1_MPAM_MASK, 1);
487 	err = __vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR0_EL1), val);
488 	if (err)
489 		ksft_test_result_skip("ID_AA64PFR0_EL1.MPAM is not writable, nothing to test\n");
490 	else
491 		ksft_test_result_pass("ID_AA64PFR0_EL1.MPAM=1 was writable\n");
492 
493 	/* Try to set MPAM=2 */
494 	val &= ~ID_AA64PFR0_EL1_MPAM_MASK;
495 	val |= FIELD_PREP(ID_AA64PFR0_EL1_MPAM_MASK, 2);
496 	err = __vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR0_EL1), val);
497 	if (err)
498 		ksft_test_result_pass("ID_AA64PFR0_EL1.MPAM not arbitrarily modifiable\n");
499 	else
500 		ksft_test_result_fail("ID_AA64PFR0_EL1.MPAM value should not be ignored\n");
501 
502 	/* And again for ID_AA64PFR1_EL1.MPAM_frac */
503 	idx = encoding_to_range_idx(SYS_ID_AA64PFR1_EL1);
504 	if ((masks[idx] & ID_AA64PFR1_EL1_MPAM_frac_MASK) == ID_AA64PFR1_EL1_MPAM_frac_MASK) {
505 		ksft_test_result_skip("ID_AA64PFR1_EL1.MPAM_frac is officially writable, nothing to test\n");
506 		return;
507 	}
508 
509 	/* Get the id register value */
510 	vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR1_EL1), &val);
511 
512 	/* Try to set MPAM_frac=0. This should always be possible. */
513 	val &= ~ID_AA64PFR1_EL1_MPAM_frac_MASK;
514 	val |= FIELD_PREP(ID_AA64PFR1_EL1_MPAM_frac_MASK, 0);
515 	err = __vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR1_EL1), val);
516 	if (err)
517 		ksft_test_result_fail("ID_AA64PFR0_EL1.MPAM_frac=0 was not accepted\n");
518 	else
519 		ksft_test_result_pass("ID_AA64PFR0_EL1.MPAM_frac=0 worked\n");
520 
521 	/* Try to set MPAM_frac=1 */
522 	val &= ~ID_AA64PFR1_EL1_MPAM_frac_MASK;
523 	val |= FIELD_PREP(ID_AA64PFR1_EL1_MPAM_frac_MASK, 1);
524 	err = __vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR1_EL1), val);
525 	if (err)
526 		ksft_test_result_skip("ID_AA64PFR1_EL1.MPAM_frac is not writable, nothing to test\n");
527 	else
528 		ksft_test_result_pass("ID_AA64PFR0_EL1.MPAM_frac=1 was writable\n");
529 
530 	/* Try to set MPAM_frac=2 */
531 	val &= ~ID_AA64PFR1_EL1_MPAM_frac_MASK;
532 	val |= FIELD_PREP(ID_AA64PFR1_EL1_MPAM_frac_MASK, 2);
533 	err = __vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR1_EL1), val);
534 	if (err)
535 		ksft_test_result_pass("ID_AA64PFR1_EL1.MPAM_frac not arbitrarily modifiable\n");
536 	else
537 		ksft_test_result_fail("ID_AA64PFR1_EL1.MPAM_frac value should not be ignored\n");
538 }
539 
540 static void test_guest_reg_read(struct kvm_vcpu *vcpu)
541 {
542 	bool done = false;
543 	struct ucall uc;
544 
545 	while (!done) {
546 		vcpu_run(vcpu);
547 
548 		switch (get_ucall(vcpu, &uc)) {
549 		case UCALL_ABORT:
550 			REPORT_GUEST_ASSERT(uc);
551 			break;
552 		case UCALL_SYNC:
553 			/* Make sure the written values are seen by guest */
554 			TEST_ASSERT_EQ(test_reg_vals[encoding_to_range_idx(uc.args[2])],
555 				       uc.args[3]);
556 			break;
557 		case UCALL_DONE:
558 			done = true;
559 			break;
560 		default:
561 			TEST_FAIL("Unexpected ucall: %lu", uc.cmd);
562 		}
563 	}
564 }
565 
566 /* Politely lifted from arch/arm64/include/asm/cache.h */
567 /* Ctypen, bits[3(n - 1) + 2 : 3(n - 1)], for n = 1 to 7 */
568 #define CLIDR_CTYPE_SHIFT(level)	(3 * (level - 1))
569 #define CLIDR_CTYPE_MASK(level)		(7 << CLIDR_CTYPE_SHIFT(level))
570 #define CLIDR_CTYPE(clidr, level)	\
571 	(((clidr) & CLIDR_CTYPE_MASK(level)) >> CLIDR_CTYPE_SHIFT(level))
572 
573 static void test_clidr(struct kvm_vcpu *vcpu)
574 {
575 	uint64_t clidr;
576 	int level;
577 
578 	vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_CLIDR_EL1), &clidr);
579 
580 	/* find the first empty level in the cache hierarchy */
581 	for (level = 1; level < 7; level++) {
582 		if (!CLIDR_CTYPE(clidr, level))
583 			break;
584 	}
585 
586 	/*
587 	 * If you have a mind-boggling 7 levels of cache, congratulations, you
588 	 * get to fix this.
589 	 */
590 	TEST_ASSERT(level <= 7, "can't find an empty level in cache hierarchy");
591 
592 	/* stick in a unified cache level */
593 	clidr |= BIT(2) << CLIDR_CTYPE_SHIFT(level);
594 
595 	vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_CLIDR_EL1), clidr);
596 	test_reg_vals[encoding_to_range_idx(SYS_CLIDR_EL1)] = clidr;
597 }
598 
599 static void test_ctr(struct kvm_vcpu *vcpu)
600 {
601 	u64 ctr;
602 
603 	vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_CTR_EL0), &ctr);
604 	ctr &= ~CTR_EL0_DIC_MASK;
605 	if (ctr & CTR_EL0_IminLine_MASK)
606 		ctr--;
607 
608 	vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_CTR_EL0), ctr);
609 	test_reg_vals[encoding_to_range_idx(SYS_CTR_EL0)] = ctr;
610 }
611 
612 static void test_vcpu_ftr_id_regs(struct kvm_vcpu *vcpu)
613 {
614 	u64 val;
615 
616 	test_clidr(vcpu);
617 	test_ctr(vcpu);
618 
619 	vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_MPIDR_EL1), &val);
620 	val++;
621 	vcpu_set_reg(vcpu, KVM_ARM64_SYS_REG(SYS_MPIDR_EL1), val);
622 
623 	test_reg_vals[encoding_to_range_idx(SYS_MPIDR_EL1)] = val;
624 	ksft_test_result_pass("%s\n", __func__);
625 }
626 
627 static void test_assert_id_reg_unchanged(struct kvm_vcpu *vcpu, uint32_t encoding)
628 {
629 	size_t idx = encoding_to_range_idx(encoding);
630 	uint64_t observed;
631 
632 	vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(encoding), &observed);
633 	TEST_ASSERT_EQ(test_reg_vals[idx], observed);
634 }
635 
636 static void test_reset_preserves_id_regs(struct kvm_vcpu *vcpu)
637 {
638 	/*
639 	 * Calls KVM_ARM_VCPU_INIT behind the scenes, which will do an
640 	 * architectural reset of the vCPU.
641 	 */
642 	aarch64_vcpu_setup(vcpu, NULL);
643 
644 	for (int i = 0; i < ARRAY_SIZE(test_regs); i++)
645 		test_assert_id_reg_unchanged(vcpu, test_regs[i].reg);
646 
647 	test_assert_id_reg_unchanged(vcpu, SYS_MPIDR_EL1);
648 	test_assert_id_reg_unchanged(vcpu, SYS_CLIDR_EL1);
649 	test_assert_id_reg_unchanged(vcpu, SYS_CTR_EL0);
650 
651 	ksft_test_result_pass("%s\n", __func__);
652 }
653 
654 int main(void)
655 {
656 	struct kvm_vcpu *vcpu;
657 	struct kvm_vm *vm;
658 	bool aarch64_only;
659 	uint64_t val, el0;
660 	int test_cnt;
661 
662 	TEST_REQUIRE(kvm_has_cap(KVM_CAP_ARM_SUPPORTED_REG_MASK_RANGES));
663 
664 	vm = vm_create_with_one_vcpu(&vcpu, guest_code);
665 
666 	/* Check for AARCH64 only system */
667 	vcpu_get_reg(vcpu, KVM_ARM64_SYS_REG(SYS_ID_AA64PFR0_EL1), &val);
668 	el0 = FIELD_GET(ARM64_FEATURE_MASK(ID_AA64PFR0_EL1_EL0), val);
669 	aarch64_only = (el0 == ID_AA64PFR0_EL1_ELx_64BIT_ONLY);
670 
671 	ksft_print_header();
672 
673 	test_cnt = ARRAY_SIZE(ftr_id_aa64dfr0_el1) + ARRAY_SIZE(ftr_id_dfr0_el1) +
674 		   ARRAY_SIZE(ftr_id_aa64isar0_el1) + ARRAY_SIZE(ftr_id_aa64isar1_el1) +
675 		   ARRAY_SIZE(ftr_id_aa64isar2_el1) + ARRAY_SIZE(ftr_id_aa64pfr0_el1) +
676 		   ARRAY_SIZE(ftr_id_aa64pfr1_el1) + ARRAY_SIZE(ftr_id_aa64mmfr0_el1) +
677 		   ARRAY_SIZE(ftr_id_aa64mmfr1_el1) + ARRAY_SIZE(ftr_id_aa64mmfr2_el1) +
678 		   ARRAY_SIZE(ftr_id_aa64zfr0_el1) - ARRAY_SIZE(test_regs) + 2 +
679 		   MPAM_IDREG_TEST;
680 
681 	ksft_set_plan(test_cnt);
682 
683 	test_vm_ftr_id_regs(vcpu, aarch64_only);
684 	test_vcpu_ftr_id_regs(vcpu);
685 	test_user_set_mpam_reg(vcpu);
686 
687 	test_guest_reg_read(vcpu);
688 
689 	test_reset_preserves_id_regs(vcpu);
690 
691 	kvm_vm_free(vm);
692 
693 	ksft_finished();
694 }
695