xref: /linux/arch/mips/mm/cerr-sb1.c (revision 13abf8130139c2ccd4962a7e5a8902be5e6cb5a7)
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 
23 #ifndef CONFIG_SIBYTE_BUS_WATCHER
24 #include <asm/io.h>
25 #include <asm/sibyte/sb1250_regs.h>
26 #include <asm/sibyte/sb1250_scd.h>
27 #endif
28 
29 /* SB1 definitions */
30 
31 /* XXX should come from config1 XXX */
32 #define SB1_CACHE_INDEX_MASK   0x1fe0
33 
34 #define CP0_ERRCTL_RECOVERABLE (1 << 31)
35 #define CP0_ERRCTL_DCACHE      (1 << 30)
36 #define CP0_ERRCTL_ICACHE      (1 << 29)
37 #define CP0_ERRCTL_MULTIBUS    (1 << 23)
38 #define CP0_ERRCTL_MC_TLB      (1 << 15)
39 #define CP0_ERRCTL_MC_TIMEOUT  (1 << 14)
40 
41 #define CP0_CERRI_TAG_PARITY   (1 << 29)
42 #define CP0_CERRI_DATA_PARITY  (1 << 28)
43 #define CP0_CERRI_EXTERNAL     (1 << 26)
44 
45 #define CP0_CERRI_IDX_VALID(c) (!((c) & CP0_CERRI_EXTERNAL))
46 #define CP0_CERRI_DATA         (CP0_CERRI_DATA_PARITY)
47 
48 #define CP0_CERRD_MULTIPLE     (1 << 31)
49 #define CP0_CERRD_TAG_STATE    (1 << 30)
50 #define CP0_CERRD_TAG_ADDRESS  (1 << 29)
51 #define CP0_CERRD_DATA_SBE     (1 << 28)
52 #define CP0_CERRD_DATA_DBE     (1 << 27)
53 #define CP0_CERRD_EXTERNAL     (1 << 26)
54 #define CP0_CERRD_LOAD         (1 << 25)
55 #define CP0_CERRD_STORE        (1 << 24)
56 #define CP0_CERRD_FILLWB       (1 << 23)
57 #define CP0_CERRD_COHERENCY    (1 << 22)
58 #define CP0_CERRD_DUPTAG       (1 << 21)
59 
60 #define CP0_CERRD_DPA_VALID(c) (!((c) & CP0_CERRD_EXTERNAL))
61 #define CP0_CERRD_IDX_VALID(c) \
62    (((c) & (CP0_CERRD_LOAD | CP0_CERRD_STORE)) ? (!((c) & CP0_CERRD_EXTERNAL)) : 0)
63 #define CP0_CERRD_CAUSES \
64    (CP0_CERRD_LOAD | CP0_CERRD_STORE | CP0_CERRD_FILLWB | CP0_CERRD_COHERENCY | CP0_CERRD_DUPTAG)
65 #define CP0_CERRD_TYPES \
66    (CP0_CERRD_TAG_STATE | CP0_CERRD_TAG_ADDRESS | CP0_CERRD_DATA_SBE | CP0_CERRD_DATA_DBE | CP0_CERRD_EXTERNAL)
67 #define CP0_CERRD_DATA         (CP0_CERRD_DATA_SBE | CP0_CERRD_DATA_DBE)
68 
69 static uint32_t	extract_ic(unsigned short addr, int data);
70 static uint32_t	extract_dc(unsigned short addr, int data);
71 
72 static inline void breakout_errctl(unsigned int val)
73 {
74 	if (val & CP0_ERRCTL_RECOVERABLE)
75 		prom_printf(" recoverable");
76 	if (val & CP0_ERRCTL_DCACHE)
77 		prom_printf(" dcache");
78 	if (val & CP0_ERRCTL_ICACHE)
79 		prom_printf(" icache");
80 	if (val & CP0_ERRCTL_MULTIBUS)
81 		prom_printf(" multiple-buserr");
82 	prom_printf("\n");
83 }
84 
85 static inline void breakout_cerri(unsigned int val)
86 {
87 	if (val & CP0_CERRI_TAG_PARITY)
88 		prom_printf(" tag-parity");
89 	if (val & CP0_CERRI_DATA_PARITY)
90 		prom_printf(" data-parity");
91 	if (val & CP0_CERRI_EXTERNAL)
92 		prom_printf(" external");
93 	prom_printf("\n");
94 }
95 
96 static inline void breakout_cerrd(unsigned int val)
97 {
98 	switch (val & CP0_CERRD_CAUSES) {
99 	case CP0_CERRD_LOAD:
100 		prom_printf(" load,");
101 		break;
102 	case CP0_CERRD_STORE:
103 		prom_printf(" store,");
104 		break;
105 	case CP0_CERRD_FILLWB:
106 		prom_printf(" fill/wb,");
107 		break;
108 	case CP0_CERRD_COHERENCY:
109 		prom_printf(" coherency,");
110 		break;
111 	case CP0_CERRD_DUPTAG:
112 		prom_printf(" duptags,");
113 		break;
114 	default:
115 		prom_printf(" NO CAUSE,");
116 		break;
117 	}
118 	if (!(val & CP0_CERRD_TYPES))
119 		prom_printf(" NO TYPE");
120 	else {
121 		if (val & CP0_CERRD_MULTIPLE)
122 			prom_printf(" multi-err");
123 		if (val & CP0_CERRD_TAG_STATE)
124 			prom_printf(" tag-state");
125 		if (val & CP0_CERRD_TAG_ADDRESS)
126 			prom_printf(" tag-address");
127 		if (val & CP0_CERRD_DATA_SBE)
128 			prom_printf(" data-SBE");
129 		if (val & CP0_CERRD_DATA_DBE)
130 			prom_printf(" data-DBE");
131 		if (val & CP0_CERRD_EXTERNAL)
132 			prom_printf(" external");
133 	}
134 	prom_printf("\n");
135 }
136 
137 #ifndef CONFIG_SIBYTE_BUS_WATCHER
138 
139 static void check_bus_watcher(void)
140 {
141 	uint32_t status, l2_err, memio_err;
142 
143 	/* Destructive read, clears register and interrupt */
144 	status = csr_in32(IOADDR(A_SCD_BUS_ERR_STATUS));
145 	/* Bit 31 is always on, but there's no #define for that */
146 	if (status & ~(1UL << 31)) {
147 		l2_err = csr_in32(IOADDR(A_BUS_L2_ERRORS));
148 		memio_err = csr_in32(IOADDR(A_BUS_MEM_IO_ERRORS));
149 		prom_printf("Bus watcher error counters: %08x %08x\n", l2_err, memio_err);
150 		prom_printf("\nLast recorded signature:\n");
151 		prom_printf("Request %02x from %d, answered by %d with Dcode %d\n",
152 		       (unsigned int)(G_SCD_BERR_TID(status) & 0x3f),
153 		       (int)(G_SCD_BERR_TID(status) >> 6),
154 		       (int)G_SCD_BERR_RID(status),
155 		       (int)G_SCD_BERR_DCODE(status));
156 	} else {
157 		prom_printf("Bus watcher indicates no error\n");
158 	}
159 }
160 #else
161 extern void check_bus_watcher(void);
162 #endif
163 
164 asmlinkage void sb1_cache_error(void)
165 {
166 	uint64_t cerr_dpa;
167 	uint32_t errctl, cerr_i, cerr_d, dpalo, dpahi, eepc, res;
168 
169 	prom_printf("Cache error exception on CPU %x:\n",
170 		    (read_c0_prid() >> 25) & 0x7);
171 
172 	__asm__ __volatile__ (
173 	"	.set	push\n\t"
174 	"	.set	mips64\n\t"
175 	"	.set	noat\n\t"
176 	"	mfc0	%0, $26\n\t"
177 	"	mfc0	%1, $27\n\t"
178 	"	mfc0	%2, $27, 1\n\t"
179 	"	dmfc0	$1, $27, 3\n\t"
180 	"	dsrl32	%3, $1, 0 \n\t"
181 	"	sll	%4, $1, 0 \n\t"
182 	"	mfc0	%5, $30\n\t"
183 	"	.set	pop"
184 	: "=r" (errctl), "=r" (cerr_i), "=r" (cerr_d),
185 	  "=r" (dpahi), "=r" (dpalo), "=r" (eepc));
186 
187 	cerr_dpa = (((uint64_t)dpahi) << 32) | dpalo;
188 	prom_printf(" c0_errorepc ==   %08x\n", eepc);
189 	prom_printf(" c0_errctl   ==   %08x", errctl);
190 	breakout_errctl(errctl);
191 	if (errctl & CP0_ERRCTL_ICACHE) {
192 		prom_printf(" c0_cerr_i   ==   %08x", cerr_i);
193 		breakout_cerri(cerr_i);
194 		if (CP0_CERRI_IDX_VALID(cerr_i)) {
195 			/* Check index of EPC, allowing for delay slot */
196 			if (((eepc & SB1_CACHE_INDEX_MASK) != (cerr_i & SB1_CACHE_INDEX_MASK)) &&
197 			    ((eepc & SB1_CACHE_INDEX_MASK) != ((cerr_i & SB1_CACHE_INDEX_MASK) - 4)))
198 				prom_printf(" cerr_i idx doesn't match eepc\n");
199 			else {
200 				res = extract_ic(cerr_i & SB1_CACHE_INDEX_MASK,
201 						 (cerr_i & CP0_CERRI_DATA) != 0);
202 				if (!(res & cerr_i))
203 					prom_printf("...didn't see indicated icache problem\n");
204 			}
205 		}
206 	}
207 	if (errctl & CP0_ERRCTL_DCACHE) {
208 		prom_printf(" c0_cerr_d   ==   %08x", cerr_d);
209 		breakout_cerrd(cerr_d);
210 		if (CP0_CERRD_DPA_VALID(cerr_d)) {
211 			prom_printf(" c0_cerr_dpa == %010llx\n", cerr_dpa);
212 			if (!CP0_CERRD_IDX_VALID(cerr_d)) {
213 				res = extract_dc(cerr_dpa & SB1_CACHE_INDEX_MASK,
214 						 (cerr_d & CP0_CERRD_DATA) != 0);
215 				if (!(res & cerr_d))
216 					prom_printf("...didn't see indicated dcache problem\n");
217 			} else {
218 				if ((cerr_dpa & SB1_CACHE_INDEX_MASK) != (cerr_d & SB1_CACHE_INDEX_MASK))
219 					prom_printf(" cerr_d idx doesn't match cerr_dpa\n");
220 				else {
221 					res = extract_dc(cerr_d & SB1_CACHE_INDEX_MASK,
222 							 (cerr_d & CP0_CERRD_DATA) != 0);
223 					if (!(res & cerr_d))
224 						prom_printf("...didn't see indicated problem\n");
225 				}
226 			}
227 		}
228 	}
229 
230 	check_bus_watcher();
231 
232 	while (1);
233 	/*
234 	 * This tends to make things get really ugly; let's just stall instead.
235 	 *    panic("Can't handle the cache error!");
236 	 */
237 }
238 
239 
240 /* Parity lookup table. */
241 static const uint8_t parity[256] = {
242 	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,
243 	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,
244 	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,
245 	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,
246 	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,
247 	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,
248 	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,
249 	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
250 };
251 
252 /* Masks to select bits for Hamming parity, mask_72_64[i] for bit[i] */
253 static const uint64_t mask_72_64[8] = {
254 	0x0738C808099264FFULL,
255 	0x38C808099264FF07ULL,
256 	0xC808099264FF0738ULL,
257 	0x08099264FF0738C8ULL,
258 	0x099264FF0738C808ULL,
259 	0x9264FF0738C80809ULL,
260 	0x64FF0738C8080992ULL,
261 	0xFF0738C808099264ULL
262 };
263 
264 /* Calculate the parity on a range of bits */
265 static char range_parity(uint64_t dword, int max, int min)
266 {
267 	char parity = 0;
268 	int i;
269 	dword >>= min;
270 	for (i=max-min; i>=0; i--) {
271 		if (dword & 0x1)
272 			parity = !parity;
273 		dword >>= 1;
274 	}
275 	return parity;
276 }
277 
278 /* Calculate the 4-bit even byte-parity for an instruction */
279 static unsigned char inst_parity(uint32_t word)
280 {
281 	int i, j;
282 	char parity = 0;
283 	for (j=0; j<4; j++) {
284 		char byte_parity = 0;
285 		for (i=0; i<8; i++) {
286 			if (word & 0x80000000)
287 				byte_parity = !byte_parity;
288 			word <<= 1;
289 		}
290 		parity <<= 1;
291 		parity |= byte_parity;
292 	}
293 	return parity;
294 }
295 
296 static uint32_t extract_ic(unsigned short addr, int data)
297 {
298 	unsigned short way;
299 	int valid;
300 	uint64_t taglo, va, tlo_tmp;
301 	uint32_t taghi, taglolo, taglohi;
302 	uint8_t lru;
303 	int res = 0;
304 
305 	prom_printf("Icache index 0x%04x  ", addr);
306 	for (way = 0; way < 4; way++) {
307 		/* Index-load-tag-I */
308 		__asm__ __volatile__ (
309 		"	.set	push		\n\t"
310 		"	.set	noreorder	\n\t"
311 		"	.set	mips64		\n\t"
312 		"	.set	noat		\n\t"
313 		"	cache	4, 0(%3)	\n\t"
314 		"	mfc0	%0, $29		\n\t"
315 		"	dmfc0	$1, $28		\n\t"
316 		"	dsrl32	%1, $1, 0	\n\t"
317 		"	sll	%2, $1, 0	\n\t"
318 		"	.set	pop"
319 		: "=r" (taghi), "=r" (taglohi), "=r" (taglolo)
320 		: "r" ((way << 13) | addr));
321 
322 		taglo = ((unsigned long long)taglohi << 32) | taglolo;
323 		if (way == 0) {
324 			lru = (taghi >> 14) & 0xff;
325 			prom_printf("[Bank %d Set 0x%02x]  LRU > %d %d %d %d > MRU\n",
326 				    ((addr >> 5) & 0x3), /* bank */
327 				    ((addr >> 7) & 0x3f), /* index */
328 				    (lru & 0x3),
329 				    ((lru >> 2) & 0x3),
330 				    ((lru >> 4) & 0x3),
331 				    ((lru >> 6) & 0x3));
332 		}
333 		va = (taglo & 0xC0000FFFFFFFE000ULL) | addr;
334 		if ((taglo & (1 << 31)) && (((taglo >> 62) & 0x3) == 3))
335 			va |= 0x3FFFF00000000000ULL;
336 		valid = ((taghi >> 29) & 1);
337 		if (valid) {
338 			tlo_tmp = taglo & 0xfff3ff;
339 			if (((taglo >> 10) & 1) ^ range_parity(tlo_tmp, 23, 0)) {
340 				prom_printf("   ** bad parity in VTag0/G/ASID\n");
341 				res |= CP0_CERRI_TAG_PARITY;
342 			}
343 			if (((taglo >> 11) & 1) ^ range_parity(taglo, 63, 24)) {
344 				prom_printf("   ** bad parity in R/VTag1\n");
345 				res |= CP0_CERRI_TAG_PARITY;
346 			}
347 		}
348 		if (valid ^ ((taghi >> 27) & 1)) {
349 			prom_printf("   ** bad parity for valid bit\n");
350 			res |= CP0_CERRI_TAG_PARITY;
351 		}
352 		prom_printf(" %d  [VA %016llx]  [Vld? %d]  raw tags: %08X-%016llX\n",
353 			    way, va, valid, taghi, taglo);
354 
355 		if (data) {
356 			uint32_t datahi, insta, instb;
357 			uint8_t predecode;
358 			int offset;
359 
360 			/* (hit all banks and ways) */
361 			for (offset = 0; offset < 4; offset++) {
362 				/* Index-load-data-I */
363 				__asm__ __volatile__ (
364 				"	.set	push\n\t"
365 				"	.set	noreorder\n\t"
366 				"	.set	mips64\n\t"
367 				"	.set	noat\n\t"
368 				"	cache	6, 0(%3)  \n\t"
369 				"	mfc0	%0, $29, 1\n\t"
370 				"	dmfc0  $1, $28, 1\n\t"
371 				"	dsrl32 %1, $1, 0 \n\t"
372 				"	sll    %2, $1, 0 \n\t"
373 				"	.set	pop         \n"
374 				: "=r" (datahi), "=r" (insta), "=r" (instb)
375 				: "r" ((way << 13) | addr | (offset << 3)));
376 				predecode = (datahi >> 8) & 0xff;
377 				if (((datahi >> 16) & 1) != (uint32_t)range_parity(predecode, 7, 0)) {
378 					prom_printf("   ** bad parity in predecode\n");
379 					res |= CP0_CERRI_DATA_PARITY;
380 				}
381 				/* XXXKW should/could check predecode bits themselves */
382 				if (((datahi >> 4) & 0xf) ^ inst_parity(insta)) {
383 					prom_printf("   ** bad parity in instruction a\n");
384 					res |= CP0_CERRI_DATA_PARITY;
385 				}
386 				if ((datahi & 0xf) ^ inst_parity(instb)) {
387 					prom_printf("   ** bad parity in instruction b\n");
388 					res |= CP0_CERRI_DATA_PARITY;
389 				}
390 				prom_printf("  %05X-%08X%08X", datahi, insta, instb);
391 			}
392 			prom_printf("\n");
393 		}
394 	}
395 	return res;
396 }
397 
398 /* Compute the ECC for a data doubleword */
399 static uint8_t dc_ecc(uint64_t dword)
400 {
401 	uint64_t t;
402 	uint32_t w;
403 	uint8_t  p;
404 	int      i;
405 
406 	p = 0;
407 	for (i = 7; i >= 0; i--)
408 	{
409 		p <<= 1;
410 		t = dword & mask_72_64[i];
411 		w = (uint32_t)(t >> 32);
412 		p ^= (parity[w>>24] ^ parity[(w>>16) & 0xFF]
413 		      ^ parity[(w>>8) & 0xFF] ^ parity[w & 0xFF]);
414 		w = (uint32_t)(t & 0xFFFFFFFF);
415 		p ^= (parity[w>>24] ^ parity[(w>>16) & 0xFF]
416 		      ^ parity[(w>>8) & 0xFF] ^ parity[w & 0xFF]);
417 	}
418 	return p;
419 }
420 
421 struct dc_state {
422 	unsigned char val;
423 	char *name;
424 };
425 
426 static struct dc_state dc_states[] = {
427 	{ 0x00, "INVALID" },
428 	{ 0x0f, "COH-SHD" },
429 	{ 0x13, "NCO-E-C" },
430 	{ 0x19, "NCO-E-D" },
431 	{ 0x16, "COH-E-C" },
432 	{ 0x1c, "COH-E-D" },
433 	{ 0xff, "*ERROR*" }
434 };
435 
436 #define DC_TAG_VALID(state) \
437     (((state) == 0xf) || ((state) == 0x13) || ((state) == 0x19) || ((state == 0x16)) || ((state) == 0x1c))
438 
439 static char *dc_state_str(unsigned char state)
440 {
441 	struct dc_state *dsc = dc_states;
442 	while (dsc->val != 0xff) {
443 		if (dsc->val == state)
444 			break;
445 		dsc++;
446 	}
447 	return dsc->name;
448 }
449 
450 static uint32_t extract_dc(unsigned short addr, int data)
451 {
452 	int valid, way;
453 	unsigned char state;
454 	uint64_t taglo, pa;
455 	uint32_t taghi, taglolo, taglohi;
456 	uint8_t ecc, lru;
457 	int res = 0;
458 
459 	prom_printf("Dcache index 0x%04x  ", addr);
460 	for (way = 0; way < 4; way++) {
461 		__asm__ __volatile__ (
462 		"	.set	push\n\t"
463 		"	.set	noreorder\n\t"
464 		"	.set	mips64\n\t"
465 		"	.set	noat\n\t"
466 		"	cache	5, 0(%3)\n\t"	/* Index-load-tag-D */
467 		"	mfc0	%0, $29, 2\n\t"
468 		"	dmfc0	$1, $28, 2\n\t"
469 		"	dsrl32	%1, $1, 0\n\t"
470 		"	sll	%2, $1, 0\n\t"
471 		"	.set	pop"
472 		: "=r" (taghi), "=r" (taglohi), "=r" (taglolo)
473 		: "r" ((way << 13) | addr));
474 
475 		taglo = ((unsigned long long)taglohi << 32) | taglolo;
476 		pa = (taglo & 0xFFFFFFE000ULL) | addr;
477 		if (way == 0) {
478 			lru = (taghi >> 14) & 0xff;
479 			prom_printf("[Bank %d Set 0x%02x]  LRU > %d %d %d %d > MRU\n",
480 				    ((addr >> 11) & 0x2) | ((addr >> 5) & 1), /* bank */
481 				    ((addr >> 6) & 0x3f), /* index */
482 				    (lru & 0x3),
483 				    ((lru >> 2) & 0x3),
484 				    ((lru >> 4) & 0x3),
485 				    ((lru >> 6) & 0x3));
486 		}
487 		state = (taghi >> 25) & 0x1f;
488 		valid = DC_TAG_VALID(state);
489 		prom_printf(" %d  [PA %010llx]  [state %s (%02x)]  raw tags: %08X-%016llX\n",
490 			    way, pa, dc_state_str(state), state, taghi, taglo);
491 		if (valid) {
492 			if (((taglo >> 11) & 1) ^ range_parity(taglo, 39, 26)) {
493 				prom_printf("   ** bad parity in PTag1\n");
494 				res |= CP0_CERRD_TAG_ADDRESS;
495 			}
496 			if (((taglo >> 10) & 1) ^ range_parity(taglo, 25, 13)) {
497 				prom_printf("   ** bad parity in PTag0\n");
498 				res |= CP0_CERRD_TAG_ADDRESS;
499 			}
500 		} else {
501 			res |= CP0_CERRD_TAG_STATE;
502 		}
503 
504 		if (data) {
505 			uint64_t datalo;
506 			uint32_t datalohi, datalolo, datahi;
507 			int offset;
508 
509 			for (offset = 0; offset < 4; offset++) {
510 				/* Index-load-data-D */
511 				__asm__ __volatile__ (
512 				"	.set	push\n\t"
513 				"	.set	noreorder\n\t"
514 				"	.set	mips64\n\t"
515 				"	.set	noat\n\t"
516 				"	cache	7, 0(%3)\n\t" /* Index-load-data-D */
517 				"	mfc0	%0, $29, 3\n\t"
518 				"	dmfc0	$1, $28, 3\n\t"
519 				"	dsrl32	%1, $1, 0 \n\t"
520 				"	sll	%2, $1, 0 \n\t"
521 				"	.set	pop"
522 				: "=r" (datahi), "=r" (datalohi), "=r" (datalolo)
523 				: "r" ((way << 13) | addr | (offset << 3)));
524 				datalo = ((unsigned long long)datalohi << 32) | datalolo;
525 				ecc = dc_ecc(datalo);
526 				if (ecc != datahi) {
527 					int bits = 0;
528 					prom_printf("  ** bad ECC (%02x %02x) ->",
529 						    datahi, ecc);
530 					ecc ^= datahi;
531 					while (ecc) {
532 						if (ecc & 1) bits++;
533 						ecc >>= 1;
534 					}
535 					res |= (bits == 1) ? CP0_CERRD_DATA_SBE : CP0_CERRD_DATA_DBE;
536 				}
537 				prom_printf("  %02X-%016llX", datahi, datalo);
538 			}
539 			prom_printf("\n");
540 		}
541 	}
542 	return res;
543 }
544