xref: /kvm-unit-tests/powerpc/sprs.c (revision 8b10d4fadc42e83fabc47fbdbe66d83a1e8f1438)
1 /*
2  * Test Special Purpose Registers
3  *
4  * Copyright 2017  Thomas Huth, Red Hat Inc.
5  *
6  * This work is licensed under the terms of the GNU LGPL, version 2.
7  *
8  * The basic idea of this test is to check whether the contents of the Special
9  * Purpose Registers (SPRs) are preserved correctly during migration. So we
10  * fill in the SPRs with a well-known value, read the values back (since not
11  * all bits might be retained in the SPRs), then wait for migration to complete
12  * (if the '-w' option has been specified) so that the user has a chance to
13  * migrate the VM. Alternatively, the test can also simply sleep a little bit
14  * with the H_CEDE hypercall, in the hope that we'll get scheduled to another
15  * host CPU and thus register contents might have changed, too (in case of
16  * bugs). Finally, we read back the values from the SPRs and compare them with
17  * the values before the migration. Mismatches are reported as test failures.
18  * Note that we do not test all SPRs since some of the registers change their
19  * content automatically, and some are only accessible with hypervisor privi-
20  * leges or have bad side effects, so we have to omit those registers.
21  */
22 #include <libcflat.h>
23 #include <util.h>
24 #include <migrate.h>
25 #include <alloc.h>
26 #include <asm/handlers.h>
27 #include <asm/hcall.h>
28 #include <asm/processor.h>
29 #include <asm/time.h>
30 #include <asm/barrier.h>
31 
32 uint64_t before[1024], after[1024];
33 
34 /* Common SPRs for all PowerPC CPUs */
35 static void set_sprs_common(uint64_t val)
36 {
37 	mtspr(9, val);		/* CTR */
38 	// mtspr(273, val);	/* SPRG1 */  /* Used by our exception handler */
39 	mtspr(274, val);	/* SPRG2 */
40 	mtspr(275, val);	/* SPRG3 */
41 }
42 
43 /* SPRs from PowerPC Operating Environment Architecture, Book III, Vers. 2.01 */
44 static void set_sprs_book3s_201(uint64_t val)
45 {
46 	mtspr(18, val);		/* DSISR */
47 	mtspr(19, val);		/* DAR */
48 	mtspr(152, val);	/* CTRL */
49 	mtspr(256, val);	/* VRSAVE */
50 	mtspr(786, val);	/* MMCRA */
51 	mtspr(795, val);	/* MMCR0 */
52 	mtspr(798, val);	/* MMCR1 */
53 }
54 
55 /* SPRs from PowerISA 2.07 Book III-S */
56 static void set_sprs_book3s_207(uint64_t val)
57 {
58 	mtspr(3, val);		/* DSCR */
59 	mtspr(13, val);		/* AMR */
60 	mtspr(17, val);		/* DSCR */
61 	mtspr(18, val);		/* DSISR */
62 	mtspr(19, val);		/* DAR */
63 	mtspr(29, val);		/* AMR */
64 	mtspr(61, val);		/* IAMR */
65 	// mtspr(152, val);	/* CTRL */  /* TODO: Needs a fix in KVM */
66 	mtspr(153, val);	/* FSCR */
67 	mtspr(157, val);	/* UAMOR */
68 	mtspr(159, val);	/* PSPB */
69 	mtspr(256, val);	/* VRSAVE */
70 	// mtspr(272, val);	/* SPRG0 */ /* Used by our exception handler */
71 	mtspr(769, val);	/* MMCR2 */
72 	mtspr(770, val);	/* MMCRA */
73 	mtspr(771, val);	/* PMC1 */
74 	mtspr(772, val);	/* PMC2 */
75 	mtspr(773, val);	/* PMC3 */
76 	mtspr(774, val);	/* PMC4 */
77 	mtspr(775, val);	/* PMC5 */
78 	mtspr(776, val);	/* PMC6 */
79 	mtspr(779, (val & 0xfffffffffbab3fffULL) | 0xfa0b2070);	/* MMCR0 */
80 	mtspr(784, val);	/* SIER */
81 	mtspr(785, val);	/* MMCR2 */
82 	mtspr(786, val);	/* MMCRA */
83 	mtspr(787, val);	/* PMC1 */
84 	mtspr(788, val);	/* PMC2 */
85 	mtspr(789, val);	/* PMC3 */
86 	mtspr(790, val);	/* PMC4 */
87 	mtspr(791, val);	/* PMC5 */
88 	mtspr(792, val);	/* PMC6 */
89 	mtspr(795, (val & 0xfffffffffbab3fffULL) | 0xfa0b2070);	/* MMCR0 */
90 	mtspr(796, val);	/* SIAR */
91 	mtspr(797, val);	/* SDAR */
92 	mtspr(798, val);	/* MMCR1 */
93 	mtspr(800, val);	/* BESCRS */
94 	mtspr(801, val);	/* BESCCRSU */
95 	mtspr(802, val);	/* BESCRR */
96 	mtspr(803, val);	/* BESCRRU */
97 	mtspr(804, val);	/* EBBHR */
98 	mtspr(805, val);	/* EBBRR */
99 	mtspr(806, val);	/* BESCR */
100 	mtspr(815, val);	/* TAR */
101 }
102 
103 /* SPRs from PowerISA 3.00 Book III */
104 static void set_sprs_book3s_300(uint64_t val)
105 {
106 	set_sprs_book3s_207(val);
107 	mtspr(48, val);		/* PIDR */
108 	mtspr(144, val);	/* TIDR */
109 	mtspr(823, val);	/* PSSCR */
110 }
111 
112 /* SPRs from Power ISA Version 3.1B */
113 static void set_sprs_book3s_31(uint64_t val)
114 {
115 	set_sprs_book3s_207(val);
116 	mtspr(48, val);		/* PIDR */
117 	/* 3.1 removes TIDR */
118 	mtspr(823, val);	/* PSSCR */
119 }
120 
121 static void set_sprs(uint64_t val)
122 {
123 	uint32_t pvr = mfspr(287);	/* Processor Version Register */
124 
125 	set_sprs_common(val);
126 
127 	switch (pvr >> 16) {
128 	case 0x39:			/* PPC970 */
129 	case 0x3C:			/* PPC970FX */
130 	case 0x44:			/* PPC970MP */
131 		set_sprs_book3s_201(val);
132 		break;
133 	case 0x4b:			/* POWER8E */
134 	case 0x4c:			/* POWER8NVL */
135 	case 0x4d:			/* POWER8 */
136 		set_sprs_book3s_207(val);
137 		break;
138 	case 0x4e:			/* POWER9 */
139 		set_sprs_book3s_300(val);
140 		break;
141 	case 0x80:                      /* POWER10 */
142 		set_sprs_book3s_31(val);
143 		break;
144 	default:
145 		puts("Warning: Unknown processor version!\n");
146 	}
147 }
148 
149 static void get_sprs_common(uint64_t *v)
150 {
151 	v[9] = mfspr(9);	/* CTR */
152 	// v[273] = mfspr(273);	/* SPRG1 */ /* Used by our exception handler */
153 	v[274] = mfspr(274);	/* SPRG2 */
154 	v[275] = mfspr(275);	/* SPRG3 */
155 }
156 
157 static void get_sprs_book3s_201(uint64_t *v)
158 {
159 	v[18] = mfspr(18);	/* DSISR */
160 	v[19] = mfspr(19);	/* DAR */
161 	v[136] = mfspr(136);	/* CTRL */
162 	v[256] = mfspr(256);	/* VRSAVE */
163 	v[786] = mfspr(786);	/* MMCRA */
164 	v[795] = mfspr(795);	/* MMCR0 */
165 	v[798] = mfspr(798);	/* MMCR1 */
166 }
167 
168 static void get_sprs_book3s_207(uint64_t *v)
169 {
170 	v[3] = mfspr(3);	/* DSCR */
171 	v[13] = mfspr(13);	/* AMR */
172 	v[17] = mfspr(17);	/* DSCR */
173 	v[18] = mfspr(18);	/* DSISR */
174 	v[19] = mfspr(19);	/* DAR */
175 	v[29] = mfspr(29);	/* AMR */
176 	v[61] = mfspr(61);	/* IAMR */
177 	// v[136] = mfspr(136);	/* CTRL */  /* TODO: Needs a fix in KVM */
178 	v[153] = mfspr(153);	/* FSCR */
179 	v[157] = mfspr(157);	/* UAMOR */
180 	v[159] = mfspr(159);	/* PSPB */
181 	v[256] = mfspr(256);	/* VRSAVE */
182 	v[259] = mfspr(259);	/* SPRG3 (read only) */
183 	// v[272] = mfspr(272);	/* SPRG0 */  /* Used by our exception handler */
184 	v[769] = mfspr(769);	/* MMCR2 */
185 	v[770] = mfspr(770);	/* MMCRA */
186 	v[771] = mfspr(771);	/* PMC1 */
187 	v[772] = mfspr(772);	/* PMC2 */
188 	v[773] = mfspr(773);	/* PMC3 */
189 	v[774] = mfspr(774);	/* PMC4 */
190 	v[775] = mfspr(775);	/* PMC5 */
191 	v[776] = mfspr(776);	/* PMC6 */
192 	v[779] = mfspr(779);	/* MMCR0 */
193 	v[780] = mfspr(780);	/* SIAR (read only) */
194 	v[781] = mfspr(781);	/* SDAR (read only) */
195 	v[782] = mfspr(782);	/* MMCR1 (read only) */
196 	v[784] = mfspr(784);	/* SIER */
197 	v[785] = mfspr(785);	/* MMCR2 */
198 	v[786] = mfspr(786);	/* MMCRA */
199 	v[787] = mfspr(787);	/* PMC1 */
200 	v[788] = mfspr(788);	/* PMC2 */
201 	v[789] = mfspr(789);	/* PMC3 */
202 	v[790] = mfspr(790);	/* PMC4 */
203 	v[791] = mfspr(791);	/* PMC5 */
204 	v[792] = mfspr(792);	/* PMC6 */
205 	v[795] = mfspr(795);	/* MMCR0 */
206 	v[796] = mfspr(796);	/* SIAR */
207 	v[797] = mfspr(797);	/* SDAR */
208 	v[798] = mfspr(798);	/* MMCR1 */
209 	v[800] = mfspr(800);	/* BESCRS */
210 	v[801] = mfspr(801);	/* BESCCRSU */
211 	v[802] = mfspr(802);	/* BESCRR */
212 	v[803] = mfspr(803);	/* BESCRRU */
213 	v[804] = mfspr(804);	/* EBBHR */
214 	v[805] = mfspr(805);	/* EBBRR */
215 	v[806] = mfspr(806);	/* BESCR */
216 	v[815] = mfspr(815);	/* TAR */
217 }
218 
219 static void get_sprs_book3s_300(uint64_t *v)
220 {
221 	get_sprs_book3s_207(v);
222 	v[48] = mfspr(48);	/* PIDR */
223 	v[144] = mfspr(144);	/* TIDR */
224 	v[823] = mfspr(823);	/* PSSCR */
225 }
226 
227 static void get_sprs_book3s_31(uint64_t *v)
228 {
229 	get_sprs_book3s_207(v);
230 	v[48] = mfspr(48);	/* PIDR */
231 	v[823] = mfspr(823);	/* PSSCR */
232 }
233 
234 static void get_sprs(uint64_t *v)
235 {
236 	uint32_t pvr = mfspr(287);	/* Processor Version Register */
237 
238 	get_sprs_common(v);
239 
240 	switch (pvr >> 16) {
241 	case 0x39:			/* PPC970 */
242 	case 0x3C:			/* PPC970FX */
243 	case 0x44:			/* PPC970MP */
244 		get_sprs_book3s_201(v);
245 		break;
246 	case 0x4b:			/* POWER8E */
247 	case 0x4c:			/* POWER8NVL */
248 	case 0x4d:			/* POWER8 */
249 		get_sprs_book3s_207(v);
250 		break;
251 	case 0x4e:			/* POWER9 */
252 		get_sprs_book3s_300(v);
253 		break;
254 	case 0x80:                      /* POWER10 */
255 		get_sprs_book3s_31(v);
256 		break;
257 	}
258 }
259 
260 int main(int argc, char **argv)
261 {
262 	int i;
263 	bool pause = false;
264 	uint64_t pat = 0xcafefacec0debabeULL;
265 	const uint64_t patterns[] = {
266 		0xcafefacec0debabeULL, ~0xcafefacec0debabeULL,
267 		0xAAAA5555AAAA5555ULL, 0x5555AAAA5555AAAAULL,
268 		0x1234567890ABCDEFULL, 0xFEDCBA0987654321ULL,
269 		-1ULL,
270 	};
271 
272 	for (i = 1; i < argc; i++) {
273 		if (!strcmp(argv[i], "-w")) {
274 			pause = true;
275 		} else if (!strcmp(argv[i], "-p")) {
276 			i += 1;
277 			if (i >= argc || *argv[i] < '0'
278 			    || *argv[i] >= '0' + ARRAY_SIZE(patterns))
279 				report_abort("Error: bad value for -p");
280 			pat ^= patterns[*argv[i] - '0'];
281 		} else if (!strcmp(argv[i], "-t")) {
282 			/* Randomize with timebase register */
283 			asm volatile("mftb %0" : "=r"(i));
284 			pat ^= i;
285 			asm volatile("mftb %0" : "=r"(i));
286 			pat ^= ~(uint64_t)i << 32;
287 		} else {
288 			report_abort("Warning: Unsupported argument: %s",
289 			             argv[i]);
290 		}
291 	}
292 
293 	printf("Settings SPRs to %#lx...\n", pat);
294 	set_sprs(pat);
295 
296 	memset(before, 0, sizeof(before));
297 	memset(after, 0, sizeof(after));
298 
299 	get_sprs(before);
300 
301 	if (pause) {
302 		migrate_once();
303 	} else {
304 		msleep(2000);
305 	}
306 
307 	get_sprs(after);
308 
309 	puts("Checking SPRs...\n");
310 	for (i = 0; i < 1024; i++) {
311 		if (before[i] != 0 || after[i] != 0)
312 			report(before[i] == after[i],
313 			       "SPR %d:\t%#018lx <==> %#018lx", i, before[i],
314 			       after[i]);
315 	}
316 
317 	return report_summary();
318 }
319