xref: /openbmc/linux/arch/mips/mm/cerr-sb1.c (revision 87c2ce3b)
1 /*
2  * Copyright (C) 2001,2002,2003 Broadcom Corporation
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * as published by the Free Software Foundation; either version 2
7  * of the License, or (at your option) any later version.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program; if not, write to the Free Software
16  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
17  */
18 #include <linux/config.h>
19 #include <linux/sched.h>
20 #include <asm/mipsregs.h>
21 #include <asm/sibyte/sb1250.h>
22 #include <asm/sibyte/sb1250_regs.h>
23 
24 #if !defined(CONFIG_SIBYTE_BUS_WATCHER) || defined(CONFIG_SIBYTE_BW_TRACE)
25 #include <asm/io.h>
26 #include <asm/sibyte/sb1250_scd.h>
27 #endif
28 
29 /*
30  * We'd like to dump the L2_ECC_TAG register on errors, but errata make
31  * that unsafe... So for now we don't.  (BCM1250/BCM112x erratum SOC-48.)
32  */
33 #undef DUMP_L2_ECC_TAG_ON_ERROR
34 
35 /* SB1 definitions */
36 
37 /* XXX should come from config1 XXX */
38 #define SB1_CACHE_INDEX_MASK   0x1fe0
39 
40 #define CP0_ERRCTL_RECOVERABLE (1 << 31)
41 #define CP0_ERRCTL_DCACHE      (1 << 30)
42 #define CP0_ERRCTL_ICACHE      (1 << 29)
43 #define CP0_ERRCTL_MULTIBUS    (1 << 23)
44 #define CP0_ERRCTL_MC_TLB      (1 << 15)
45 #define CP0_ERRCTL_MC_TIMEOUT  (1 << 14)
46 
47 #define CP0_CERRI_TAG_PARITY   (1 << 29)
48 #define CP0_CERRI_DATA_PARITY  (1 << 28)
49 #define CP0_CERRI_EXTERNAL     (1 << 26)
50 
51 #define CP0_CERRI_IDX_VALID(c) (!((c) & CP0_CERRI_EXTERNAL))
52 #define CP0_CERRI_DATA         (CP0_CERRI_DATA_PARITY)
53 
54 #define CP0_CERRD_MULTIPLE     (1 << 31)
55 #define CP0_CERRD_TAG_STATE    (1 << 30)
56 #define CP0_CERRD_TAG_ADDRESS  (1 << 29)
57 #define CP0_CERRD_DATA_SBE     (1 << 28)
58 #define CP0_CERRD_DATA_DBE     (1 << 27)
59 #define CP0_CERRD_EXTERNAL     (1 << 26)
60 #define CP0_CERRD_LOAD         (1 << 25)
61 #define CP0_CERRD_STORE        (1 << 24)
62 #define CP0_CERRD_FILLWB       (1 << 23)
63 #define CP0_CERRD_COHERENCY    (1 << 22)
64 #define CP0_CERRD_DUPTAG       (1 << 21)
65 
66 #define CP0_CERRD_DPA_VALID(c) (!((c) & CP0_CERRD_EXTERNAL))
67 #define CP0_CERRD_IDX_VALID(c) \
68    (((c) & (CP0_CERRD_LOAD | CP0_CERRD_STORE)) ? (!((c) & CP0_CERRD_EXTERNAL)) : 0)
69 #define CP0_CERRD_CAUSES \
70    (CP0_CERRD_LOAD | CP0_CERRD_STORE | CP0_CERRD_FILLWB | CP0_CERRD_COHERENCY | CP0_CERRD_DUPTAG)
71 #define CP0_CERRD_TYPES \
72    (CP0_CERRD_TAG_STATE | CP0_CERRD_TAG_ADDRESS | CP0_CERRD_DATA_SBE | CP0_CERRD_DATA_DBE | CP0_CERRD_EXTERNAL)
73 #define CP0_CERRD_DATA         (CP0_CERRD_DATA_SBE | CP0_CERRD_DATA_DBE)
74 
75 static uint32_t	extract_ic(unsigned short addr, int data);
76 static uint32_t	extract_dc(unsigned short addr, int data);
77 
78 static inline void breakout_errctl(unsigned int val)
79 {
80 	if (val & CP0_ERRCTL_RECOVERABLE)
81 		prom_printf(" recoverable");
82 	if (val & CP0_ERRCTL_DCACHE)
83 		prom_printf(" dcache");
84 	if (val & CP0_ERRCTL_ICACHE)
85 		prom_printf(" icache");
86 	if (val & CP0_ERRCTL_MULTIBUS)
87 		prom_printf(" multiple-buserr");
88 	prom_printf("\n");
89 }
90 
91 static inline void breakout_cerri(unsigned int val)
92 {
93 	if (val & CP0_CERRI_TAG_PARITY)
94 		prom_printf(" tag-parity");
95 	if (val & CP0_CERRI_DATA_PARITY)
96 		prom_printf(" data-parity");
97 	if (val & CP0_CERRI_EXTERNAL)
98 		prom_printf(" external");
99 	prom_printf("\n");
100 }
101 
102 static inline void breakout_cerrd(unsigned int val)
103 {
104 	switch (val & CP0_CERRD_CAUSES) {
105 	case CP0_CERRD_LOAD:
106 		prom_printf(" load,");
107 		break;
108 	case CP0_CERRD_STORE:
109 		prom_printf(" store,");
110 		break;
111 	case CP0_CERRD_FILLWB:
112 		prom_printf(" fill/wb,");
113 		break;
114 	case CP0_CERRD_COHERENCY:
115 		prom_printf(" coherency,");
116 		break;
117 	case CP0_CERRD_DUPTAG:
118 		prom_printf(" duptags,");
119 		break;
120 	default:
121 		prom_printf(" NO CAUSE,");
122 		break;
123 	}
124 	if (!(val & CP0_CERRD_TYPES))
125 		prom_printf(" NO TYPE");
126 	else {
127 		if (val & CP0_CERRD_MULTIPLE)
128 			prom_printf(" multi-err");
129 		if (val & CP0_CERRD_TAG_STATE)
130 			prom_printf(" tag-state");
131 		if (val & CP0_CERRD_TAG_ADDRESS)
132 			prom_printf(" tag-address");
133 		if (val & CP0_CERRD_DATA_SBE)
134 			prom_printf(" data-SBE");
135 		if (val & CP0_CERRD_DATA_DBE)
136 			prom_printf(" data-DBE");
137 		if (val & CP0_CERRD_EXTERNAL)
138 			prom_printf(" external");
139 	}
140 	prom_printf("\n");
141 }
142 
143 #ifndef CONFIG_SIBYTE_BUS_WATCHER
144 
145 static void check_bus_watcher(void)
146 {
147 	uint32_t status, l2_err, memio_err;
148 #ifdef DUMP_L2_ECC_TAG_ON_ERROR
149 	uint64_t l2_tag;
150 #endif
151 
152 	/* Destructive read, clears register and interrupt */
153 	status = csr_in32(IOADDR(A_SCD_BUS_ERR_STATUS));
154 	/* Bit 31 is always on, but there's no #define for that */
155 	if (status & ~(1UL << 31)) {
156 		l2_err = csr_in32(IOADDR(A_BUS_L2_ERRORS));
157 #ifdef DUMP_L2_ECC_TAG_ON_ERROR
158 		l2_tag = in64(IO_SPACE_BASE | A_L2_ECC_TAG);
159 #endif
160 		memio_err = csr_in32(IOADDR(A_BUS_MEM_IO_ERRORS));
161 		prom_printf("Bus watcher error counters: %08x %08x\n", l2_err, memio_err);
162 		prom_printf("\nLast recorded signature:\n");
163 		prom_printf("Request %02x from %d, answered by %d with Dcode %d\n",
164 		       (unsigned int)(G_SCD_BERR_TID(status) & 0x3f),
165 		       (int)(G_SCD_BERR_TID(status) >> 6),
166 		       (int)G_SCD_BERR_RID(status),
167 		       (int)G_SCD_BERR_DCODE(status));
168 #ifdef DUMP_L2_ECC_TAG_ON_ERROR
169 		prom_printf("Last L2 tag w/ bad ECC: %016llx\n", l2_tag);
170 #endif
171 	} else {
172 		prom_printf("Bus watcher indicates no error\n");
173 	}
174 }
175 #else
176 extern void check_bus_watcher(void);
177 #endif
178 
179 asmlinkage void sb1_cache_error(void)
180 {
181 	uint64_t cerr_dpa;
182 	uint32_t errctl, cerr_i, cerr_d, dpalo, dpahi, eepc, res;
183 
184 #ifdef CONFIG_SIBYTE_BW_TRACE
185 	/* Freeze the trace buffer now */
186 #if defined(CONFIG_SIBYTE_BCM1x55) || defined(CONFIG_SIBYTE_BCM1x80)
187 	csr_out32(M_BCM1480_SCD_TRACE_CFG_FREEZE, IO_SPACE_BASE | A_SCD_TRACE_CFG);
188 #else
189 	csr_out32(M_SCD_TRACE_CFG_FREEZE, IO_SPACE_BASE | A_SCD_TRACE_CFG);
190 #endif
191 	prom_printf("Trace buffer frozen\n");
192 #endif
193 
194 	prom_printf("Cache error exception on CPU %x:\n",
195 		    (read_c0_prid() >> 25) & 0x7);
196 
197 	__asm__ __volatile__ (
198 	"	.set	push\n\t"
199 	"	.set	mips64\n\t"
200 	"	.set	noat\n\t"
201 	"	mfc0	%0, $26\n\t"
202 	"	mfc0	%1, $27\n\t"
203 	"	mfc0	%2, $27, 1\n\t"
204 	"	dmfc0	$1, $27, 3\n\t"
205 	"	dsrl32	%3, $1, 0 \n\t"
206 	"	sll	%4, $1, 0 \n\t"
207 	"	mfc0	%5, $30\n\t"
208 	"	.set	pop"
209 	: "=r" (errctl), "=r" (cerr_i), "=r" (cerr_d),
210 	  "=r" (dpahi), "=r" (dpalo), "=r" (eepc));
211 
212 	cerr_dpa = (((uint64_t)dpahi) << 32) | dpalo;
213 	prom_printf(" c0_errorepc ==   %08x\n", eepc);
214 	prom_printf(" c0_errctl   ==   %08x", errctl);
215 	breakout_errctl(errctl);
216 	if (errctl & CP0_ERRCTL_ICACHE) {
217 		prom_printf(" c0_cerr_i   ==   %08x", cerr_i);
218 		breakout_cerri(cerr_i);
219 		if (CP0_CERRI_IDX_VALID(cerr_i)) {
220 			/* Check index of EPC, allowing for delay slot */
221 			if (((eepc & SB1_CACHE_INDEX_MASK) != (cerr_i & SB1_CACHE_INDEX_MASK)) &&
222 			    ((eepc & SB1_CACHE_INDEX_MASK) != ((cerr_i & SB1_CACHE_INDEX_MASK) - 4)))
223 				prom_printf(" cerr_i idx doesn't match eepc\n");
224 			else {
225 				res = extract_ic(cerr_i & SB1_CACHE_INDEX_MASK,
226 						 (cerr_i & CP0_CERRI_DATA) != 0);
227 				if (!(res & cerr_i))
228 					prom_printf("...didn't see indicated icache problem\n");
229 			}
230 		}
231 	}
232 	if (errctl & CP0_ERRCTL_DCACHE) {
233 		prom_printf(" c0_cerr_d   ==   %08x", cerr_d);
234 		breakout_cerrd(cerr_d);
235 		if (CP0_CERRD_DPA_VALID(cerr_d)) {
236 			prom_printf(" c0_cerr_dpa == %010llx\n", cerr_dpa);
237 			if (!CP0_CERRD_IDX_VALID(cerr_d)) {
238 				res = extract_dc(cerr_dpa & SB1_CACHE_INDEX_MASK,
239 						 (cerr_d & CP0_CERRD_DATA) != 0);
240 				if (!(res & cerr_d))
241 					prom_printf("...didn't see indicated dcache problem\n");
242 			} else {
243 				if ((cerr_dpa & SB1_CACHE_INDEX_MASK) != (cerr_d & SB1_CACHE_INDEX_MASK))
244 					prom_printf(" cerr_d idx doesn't match cerr_dpa\n");
245 				else {
246 					res = extract_dc(cerr_d & SB1_CACHE_INDEX_MASK,
247 							 (cerr_d & CP0_CERRD_DATA) != 0);
248 					if (!(res & cerr_d))
249 						prom_printf("...didn't see indicated problem\n");
250 				}
251 			}
252 		}
253 	}
254 
255 	check_bus_watcher();
256 
257 	/*
258 	 * Calling panic() when a fatal cache error occurs scrambles the
259 	 * state of the system (and the cache), making it difficult to
260 	 * investigate after the fact.  However, if you just stall the CPU,
261 	 * the other CPU may keep on running, which is typically very
262 	 * undesirable.
263 	 */
264 #ifdef CONFIG_SB1_CERR_STALL
265 	while (1)
266 		;
267 #else
268 	panic("unhandled cache error");
269 #endif
270 }
271 
272 
273 /* Parity lookup table. */
274 static const uint8_t parity[256] = {
275 	0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,
276 	1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,
277 	1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,
278 	0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,
279 	1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,
280 	0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,
281 	0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0,1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,
282 	1,0,0,1,0,1,1,0,0,1,1,0,1,0,0,1,0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0
283 };
284 
285 /* Masks to select bits for Hamming parity, mask_72_64[i] for bit[i] */
286 static const uint64_t mask_72_64[8] = {
287 	0x0738C808099264FFULL,
288 	0x38C808099264FF07ULL,
289 	0xC808099264FF0738ULL,
290 	0x08099264FF0738C8ULL,
291 	0x099264FF0738C808ULL,
292 	0x9264FF0738C80809ULL,
293 	0x64FF0738C8080992ULL,
294 	0xFF0738C808099264ULL
295 };
296 
297 /* Calculate the parity on a range of bits */
298 static char range_parity(uint64_t dword, int max, int min)
299 {
300 	char parity = 0;
301 	int i;
302 	dword >>= min;
303 	for (i=max-min; i>=0; i--) {
304 		if (dword & 0x1)
305 			parity = !parity;
306 		dword >>= 1;
307 	}
308 	return parity;
309 }
310 
311 /* Calculate the 4-bit even byte-parity for an instruction */
312 static unsigned char inst_parity(uint32_t word)
313 {
314 	int i, j;
315 	char parity = 0;
316 	for (j=0; j<4; j++) {
317 		char byte_parity = 0;
318 		for (i=0; i<8; i++) {
319 			if (word & 0x80000000)
320 				byte_parity = !byte_parity;
321 			word <<= 1;
322 		}
323 		parity <<= 1;
324 		parity |= byte_parity;
325 	}
326 	return parity;
327 }
328 
329 static uint32_t extract_ic(unsigned short addr, int data)
330 {
331 	unsigned short way;
332 	int valid;
333 	uint64_t taglo, va, tlo_tmp;
334 	uint32_t taghi, taglolo, taglohi;
335 	uint8_t lru;
336 	int res = 0;
337 
338 	prom_printf("Icache index 0x%04x  ", addr);
339 	for (way = 0; way < 4; way++) {
340 		/* Index-load-tag-I */
341 		__asm__ __volatile__ (
342 		"	.set	push		\n\t"
343 		"	.set	noreorder	\n\t"
344 		"	.set	mips64		\n\t"
345 		"	.set	noat		\n\t"
346 		"	cache	4, 0(%3)	\n\t"
347 		"	mfc0	%0, $29		\n\t"
348 		"	dmfc0	$1, $28		\n\t"
349 		"	dsrl32	%1, $1, 0	\n\t"
350 		"	sll	%2, $1, 0	\n\t"
351 		"	.set	pop"
352 		: "=r" (taghi), "=r" (taglohi), "=r" (taglolo)
353 		: "r" ((way << 13) | addr));
354 
355 		taglo = ((unsigned long long)taglohi << 32) | taglolo;
356 		if (way == 0) {
357 			lru = (taghi >> 14) & 0xff;
358 			prom_printf("[Bank %d Set 0x%02x]  LRU > %d %d %d %d > MRU\n",
359 				    ((addr >> 5) & 0x3), /* bank */
360 				    ((addr >> 7) & 0x3f), /* index */
361 				    (lru & 0x3),
362 				    ((lru >> 2) & 0x3),
363 				    ((lru >> 4) & 0x3),
364 				    ((lru >> 6) & 0x3));
365 		}
366 		va = (taglo & 0xC0000FFFFFFFE000ULL) | addr;
367 		if ((taglo & (1 << 31)) && (((taglo >> 62) & 0x3) == 3))
368 			va |= 0x3FFFF00000000000ULL;
369 		valid = ((taghi >> 29) & 1);
370 		if (valid) {
371 			tlo_tmp = taglo & 0xfff3ff;
372 			if (((taglo >> 10) & 1) ^ range_parity(tlo_tmp, 23, 0)) {
373 				prom_printf("   ** bad parity in VTag0/G/ASID\n");
374 				res |= CP0_CERRI_TAG_PARITY;
375 			}
376 			if (((taglo >> 11) & 1) ^ range_parity(taglo, 63, 24)) {
377 				prom_printf("   ** bad parity in R/VTag1\n");
378 				res |= CP0_CERRI_TAG_PARITY;
379 			}
380 		}
381 		if (valid ^ ((taghi >> 27) & 1)) {
382 			prom_printf("   ** bad parity for valid bit\n");
383 			res |= CP0_CERRI_TAG_PARITY;
384 		}
385 		prom_printf(" %d  [VA %016llx]  [Vld? %d]  raw tags: %08X-%016llX\n",
386 			    way, va, valid, taghi, taglo);
387 
388 		if (data) {
389 			uint32_t datahi, insta, instb;
390 			uint8_t predecode;
391 			int offset;
392 
393 			/* (hit all banks and ways) */
394 			for (offset = 0; offset < 4; offset++) {
395 				/* Index-load-data-I */
396 				__asm__ __volatile__ (
397 				"	.set	push\n\t"
398 				"	.set	noreorder\n\t"
399 				"	.set	mips64\n\t"
400 				"	.set	noat\n\t"
401 				"	cache	6, 0(%3)  \n\t"
402 				"	mfc0	%0, $29, 1\n\t"
403 				"	dmfc0  $1, $28, 1\n\t"
404 				"	dsrl32 %1, $1, 0 \n\t"
405 				"	sll    %2, $1, 0 \n\t"
406 				"	.set	pop         \n"
407 				: "=r" (datahi), "=r" (insta), "=r" (instb)
408 				: "r" ((way << 13) | addr | (offset << 3)));
409 				predecode = (datahi >> 8) & 0xff;
410 				if (((datahi >> 16) & 1) != (uint32_t)range_parity(predecode, 7, 0)) {
411 					prom_printf("   ** bad parity in predecode\n");
412 					res |= CP0_CERRI_DATA_PARITY;
413 				}
414 				/* XXXKW should/could check predecode bits themselves */
415 				if (((datahi >> 4) & 0xf) ^ inst_parity(insta)) {
416 					prom_printf("   ** bad parity in instruction a\n");
417 					res |= CP0_CERRI_DATA_PARITY;
418 				}
419 				if ((datahi & 0xf) ^ inst_parity(instb)) {
420 					prom_printf("   ** bad parity in instruction b\n");
421 					res |= CP0_CERRI_DATA_PARITY;
422 				}
423 				prom_printf("  %05X-%08X%08X", datahi, insta, instb);
424 			}
425 			prom_printf("\n");
426 		}
427 	}
428 	return res;
429 }
430 
431 /* Compute the ECC for a data doubleword */
432 static uint8_t dc_ecc(uint64_t dword)
433 {
434 	uint64_t t;
435 	uint32_t w;
436 	uint8_t  p;
437 	int      i;
438 
439 	p = 0;
440 	for (i = 7; i >= 0; i--)
441 	{
442 		p <<= 1;
443 		t = dword & mask_72_64[i];
444 		w = (uint32_t)(t >> 32);
445 		p ^= (parity[w>>24] ^ parity[(w>>16) & 0xFF]
446 		      ^ parity[(w>>8) & 0xFF] ^ parity[w & 0xFF]);
447 		w = (uint32_t)(t & 0xFFFFFFFF);
448 		p ^= (parity[w>>24] ^ parity[(w>>16) & 0xFF]
449 		      ^ parity[(w>>8) & 0xFF] ^ parity[w & 0xFF]);
450 	}
451 	return p;
452 }
453 
454 struct dc_state {
455 	unsigned char val;
456 	char *name;
457 };
458 
459 static struct dc_state dc_states[] = {
460 	{ 0x00, "INVALID" },
461 	{ 0x0f, "COH-SHD" },
462 	{ 0x13, "NCO-E-C" },
463 	{ 0x19, "NCO-E-D" },
464 	{ 0x16, "COH-E-C" },
465 	{ 0x1c, "COH-E-D" },
466 	{ 0xff, "*ERROR*" }
467 };
468 
469 #define DC_TAG_VALID(state) \
470     (((state) == 0x0) || ((state) == 0xf) || ((state) == 0x13) || \
471      ((state) == 0x19) || ((state) == 0x16) || ((state) == 0x1c))
472 
473 static char *dc_state_str(unsigned char state)
474 {
475 	struct dc_state *dsc = dc_states;
476 	while (dsc->val != 0xff) {
477 		if (dsc->val == state)
478 			break;
479 		dsc++;
480 	}
481 	return dsc->name;
482 }
483 
484 static uint32_t extract_dc(unsigned short addr, int data)
485 {
486 	int valid, way;
487 	unsigned char state;
488 	uint64_t taglo, pa;
489 	uint32_t taghi, taglolo, taglohi;
490 	uint8_t ecc, lru;
491 	int res = 0;
492 
493 	prom_printf("Dcache index 0x%04x  ", addr);
494 	for (way = 0; way < 4; way++) {
495 		__asm__ __volatile__ (
496 		"	.set	push\n\t"
497 		"	.set	noreorder\n\t"
498 		"	.set	mips64\n\t"
499 		"	.set	noat\n\t"
500 		"	cache	5, 0(%3)\n\t"	/* Index-load-tag-D */
501 		"	mfc0	%0, $29, 2\n\t"
502 		"	dmfc0	$1, $28, 2\n\t"
503 		"	dsrl32	%1, $1, 0\n\t"
504 		"	sll	%2, $1, 0\n\t"
505 		"	.set	pop"
506 		: "=r" (taghi), "=r" (taglohi), "=r" (taglolo)
507 		: "r" ((way << 13) | addr));
508 
509 		taglo = ((unsigned long long)taglohi << 32) | taglolo;
510 		pa = (taglo & 0xFFFFFFE000ULL) | addr;
511 		if (way == 0) {
512 			lru = (taghi >> 14) & 0xff;
513 			prom_printf("[Bank %d Set 0x%02x]  LRU > %d %d %d %d > MRU\n",
514 				    ((addr >> 11) & 0x2) | ((addr >> 5) & 1), /* bank */
515 				    ((addr >> 6) & 0x3f), /* index */
516 				    (lru & 0x3),
517 				    ((lru >> 2) & 0x3),
518 				    ((lru >> 4) & 0x3),
519 				    ((lru >> 6) & 0x3));
520 		}
521 		state = (taghi >> 25) & 0x1f;
522 		valid = DC_TAG_VALID(state);
523 		prom_printf(" %d  [PA %010llx]  [state %s (%02x)]  raw tags: %08X-%016llX\n",
524 			    way, pa, dc_state_str(state), state, taghi, taglo);
525 		if (valid) {
526 			if (((taglo >> 11) & 1) ^ range_parity(taglo, 39, 26)) {
527 				prom_printf("   ** bad parity in PTag1\n");
528 				res |= CP0_CERRD_TAG_ADDRESS;
529 			}
530 			if (((taglo >> 10) & 1) ^ range_parity(taglo, 25, 13)) {
531 				prom_printf("   ** bad parity in PTag0\n");
532 				res |= CP0_CERRD_TAG_ADDRESS;
533 			}
534 		} else {
535 			res |= CP0_CERRD_TAG_STATE;
536 		}
537 
538 		if (data) {
539 			uint64_t datalo;
540 			uint32_t datalohi, datalolo, datahi;
541 			int offset;
542 			char bad_ecc = 0;
543 
544 			for (offset = 0; offset < 4; offset++) {
545 				/* Index-load-data-D */
546 				__asm__ __volatile__ (
547 				"	.set	push\n\t"
548 				"	.set	noreorder\n\t"
549 				"	.set	mips64\n\t"
550 				"	.set	noat\n\t"
551 				"	cache	7, 0(%3)\n\t" /* Index-load-data-D */
552 				"	mfc0	%0, $29, 3\n\t"
553 				"	dmfc0	$1, $28, 3\n\t"
554 				"	dsrl32	%1, $1, 0 \n\t"
555 				"	sll	%2, $1, 0 \n\t"
556 				"	.set	pop"
557 				: "=r" (datahi), "=r" (datalohi), "=r" (datalolo)
558 				: "r" ((way << 13) | addr | (offset << 3)));
559 				datalo = ((unsigned long long)datalohi << 32) | datalolo;
560 				ecc = dc_ecc(datalo);
561 				if (ecc != datahi) {
562 					int bits = 0;
563 					bad_ecc |= 1 << (3-offset);
564 					ecc ^= datahi;
565 					while (ecc) {
566 						if (ecc & 1) bits++;
567 						ecc >>= 1;
568 					}
569 					res |= (bits == 1) ? CP0_CERRD_DATA_SBE : CP0_CERRD_DATA_DBE;
570 				}
571 				prom_printf("  %02X-%016llX", datahi, datalo);
572 			}
573 			prom_printf("\n");
574 			if (bad_ecc)
575 				prom_printf("  dwords w/ bad ECC: %d %d %d %d\n",
576 					    !!(bad_ecc & 8), !!(bad_ecc & 4),
577 					    !!(bad_ecc & 2), !!(bad_ecc & 1));
578 		}
579 	}
580 	return res;
581 }
582