Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 569 insertions, 0 deletions

diff --git a/arch/mips/mm/cerr-sb1.c b/arch/mips/mm/cerr-sb1.c
new file mode 100644
index 000000000..a3c02df19
--- /dev/null
+++ b/arch/mips/mm/cerr-sb1.c
@@ -0,0 +1,569 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2001,2002,2003 Broadcom Corporation
+ */
+#include <linux/sched.h>
+#include <asm/mipsregs.h>
+#include <asm/sibyte/sb1250.h>
+#include <asm/sibyte/sb1250_regs.h>
+
+#if !defined(CONFIG_SIBYTE_BUS_WATCHER) || defined(CONFIG_SIBYTE_BW_TRACE)
+#include <asm/io.h>
+#include <asm/sibyte/sb1250_scd.h>
+#endif
+
+/*
+ * We'd like to dump the L2_ECC_TAG register on errors, but errata make
+ * that unsafe... So for now we don't.	(BCM1250/BCM112x erratum SOC-48.)
+ */
+#undef DUMP_L2_ECC_TAG_ON_ERROR
+
+/* SB1 definitions */
+
+/* XXX should come from config1 XXX */
+#define SB1_CACHE_INDEX_MASK   0x1fe0
+
+#define CP0_ERRCTL_RECOVERABLE (1 << 31)
+#define CP0_ERRCTL_DCACHE      (1 << 30)
+#define CP0_ERRCTL_ICACHE      (1 << 29)
+#define CP0_ERRCTL_MULTIBUS    (1 << 23)
+#define CP0_ERRCTL_MC_TLB      (1 << 15)
+#define CP0_ERRCTL_MC_TIMEOUT  (1 << 14)
+
+#define CP0_CERRI_TAG_PARITY   (1 << 29)
+#define CP0_CERRI_DATA_PARITY  (1 << 28)
+#define CP0_CERRI_EXTERNAL     (1 << 26)
+
+#define CP0_CERRI_IDX_VALID(c) (!((c) & CP0_CERRI_EXTERNAL))
+#define CP0_CERRI_DATA	       (CP0_CERRI_DATA_PARITY)
+
+#define CP0_CERRD_MULTIPLE     (1 << 31)
+#define CP0_CERRD_TAG_STATE    (1 << 30)
+#define CP0_CERRD_TAG_ADDRESS  (1 << 29)
+#define CP0_CERRD_DATA_SBE     (1 << 28)
+#define CP0_CERRD_DATA_DBE     (1 << 27)
+#define CP0_CERRD_EXTERNAL     (1 << 26)
+#define CP0_CERRD_LOAD	       (1 << 25)
+#define CP0_CERRD_STORE	       (1 << 24)
+#define CP0_CERRD_FILLWB       (1 << 23)
+#define CP0_CERRD_COHERENCY    (1 << 22)
+#define CP0_CERRD_DUPTAG       (1 << 21)
+
+#define CP0_CERRD_DPA_VALID(c) (!((c) & CP0_CERRD_EXTERNAL))
+#define CP0_CERRD_IDX_VALID(c) \
+   (((c) & (CP0_CERRD_LOAD | CP0_CERRD_STORE)) ? (!((c) & CP0_CERRD_EXTERNAL)) : 0)
+#define CP0_CERRD_CAUSES \
+   (CP0_CERRD_LOAD | CP0_CERRD_STORE | CP0_CERRD_FILLWB | CP0_CERRD_COHERENCY | CP0_CERRD_DUPTAG)
+#define CP0_CERRD_TYPES \
+   (CP0_CERRD_TAG_STATE | CP0_CERRD_TAG_ADDRESS | CP0_CERRD_DATA_SBE | CP0_CERRD_DATA_DBE | CP0_CERRD_EXTERNAL)
+#define CP0_CERRD_DATA	       (CP0_CERRD_DATA_SBE | CP0_CERRD_DATA_DBE)
+
+static uint32_t extract_ic(unsigned short addr, int data);
+static uint32_t extract_dc(unsigned short addr, int data);
+
+static inline void breakout_errctl(unsigned int val)
+{
+	if (val & CP0_ERRCTL_RECOVERABLE)
+		printk(" recoverable");
+	if (val & CP0_ERRCTL_DCACHE)
+		printk(" dcache");
+	if (val & CP0_ERRCTL_ICACHE)
+		printk(" icache");
+	if (val & CP0_ERRCTL_MULTIBUS)
+		printk(" multiple-buserr");
+	printk("\n");
+}
+
+static inline void breakout_cerri(unsigned int val)
+{
+	if (val & CP0_CERRI_TAG_PARITY)
+		printk(" tag-parity");
+	if (val & CP0_CERRI_DATA_PARITY)
+		printk(" data-parity");
+	if (val & CP0_CERRI_EXTERNAL)
+		printk(" external");
+	printk("\n");
+}
+
+static inline void breakout_cerrd(unsigned int val)
+{
+	switch (val & CP0_CERRD_CAUSES) {
+	case CP0_CERRD_LOAD:
+		printk(" load,");
+		break;
+	case CP0_CERRD_STORE:
+		printk(" store,");
+		break;
+	case CP0_CERRD_FILLWB:
+		printk(" fill/wb,");
+		break;
+	case CP0_CERRD_COHERENCY:
+		printk(" coherency,");
+		break;
+	case CP0_CERRD_DUPTAG:
+		printk(" duptags,");
+		break;
+	default:
+		printk(" NO CAUSE,");
+		break;
+	}
+	if (!(val & CP0_CERRD_TYPES))
+		printk(" NO TYPE");
+	else {
+		if (val & CP0_CERRD_MULTIPLE)
+			printk(" multi-err");
+		if (val & CP0_CERRD_TAG_STATE)
+			printk(" tag-state");
+		if (val & CP0_CERRD_TAG_ADDRESS)
+			printk(" tag-address");
+		if (val & CP0_CERRD_DATA_SBE)
+			printk(" data-SBE");
+		if (val & CP0_CERRD_DATA_DBE)
+			printk(" data-DBE");
+		if (val & CP0_CERRD_EXTERNAL)
+			printk(" external");
+	}
+	printk("\n");
+}
+
+#ifndef CONFIG_SIBYTE_BUS_WATCHER
+
+static void check_bus_watcher(void)
+{
+	uint32_t status, l2_err, memio_err;
+#ifdef DUMP_L2_ECC_TAG_ON_ERROR
+	uint64_t l2_tag;
+#endif
+
+	/* Destructive read, clears register and interrupt */
+	status = csr_in32(IOADDR(A_SCD_BUS_ERR_STATUS));
+	/* Bit 31 is always on, but there's no #define for that */
+	if (status & ~(1UL << 31)) {
+		l2_err = csr_in32(IOADDR(A_BUS_L2_ERRORS));
+#ifdef DUMP_L2_ECC_TAG_ON_ERROR
+		l2_tag = in64(IOADDR(A_L2_ECC_TAG));
+#endif
+		memio_err = csr_in32(IOADDR(A_BUS_MEM_IO_ERRORS));
+		printk("Bus watcher error counters: %08x %08x\n", l2_err, memio_err);
+		printk("\nLast recorded signature:\n");
+		printk("Request %02x from %d, answered by %d with Dcode %d\n",
+		       (unsigned int)(G_SCD_BERR_TID(status) & 0x3f),
+		       (int)(G_SCD_BERR_TID(status) >> 6),
+		       (int)G_SCD_BERR_RID(status),
+		       (int)G_SCD_BERR_DCODE(status));
+#ifdef DUMP_L2_ECC_TAG_ON_ERROR
+		printk("Last L2 tag w/ bad ECC: %016llx\n", l2_tag);
+#endif
+	} else {
+		printk("Bus watcher indicates no error\n");
+	}
+}
+#else
+extern void check_bus_watcher(void);
+#endif
+
+asmlinkage void sb1_cache_error(void)
+{
+	uint32_t errctl, cerr_i, cerr_d, dpalo, dpahi, eepc, res;
+	unsigned long long cerr_dpa;
+
+#ifdef CONFIG_SIBYTE_BW_TRACE
+	/* Freeze the trace buffer now */
+	csr_out32(M_SCD_TRACE_CFG_FREEZE, IOADDR(A_SCD_TRACE_CFG));
+	printk("Trace buffer frozen\n");
+#endif
+
+	printk("Cache error exception on CPU %x:\n",
+	       (read_c0_prid() >> 25) & 0x7);
+
+	__asm__ __volatile__ (
+	"	.set	push\n\t"
+	"	.set	mips64\n\t"
+	"	.set	noat\n\t"
+	"	mfc0	%0, $26\n\t"
+	"	mfc0	%1, $27\n\t"
+	"	mfc0	%2, $27, 1\n\t"
+	"	dmfc0	$1, $27, 3\n\t"
+	"	dsrl32	%3, $1, 0 \n\t"
+	"	sll	%4, $1, 0 \n\t"
+	"	mfc0	%5, $30\n\t"
+	"	.set	pop"
+	: "=r" (errctl), "=r" (cerr_i), "=r" (cerr_d),
+	  "=r" (dpahi), "=r" (dpalo), "=r" (eepc));
+
+	cerr_dpa = (((uint64_t)dpahi) << 32) | dpalo;
+	printk(" c0_errorepc ==	  %08x\n", eepc);
+	printk(" c0_errctl   ==	  %08x", errctl);
+	breakout_errctl(errctl);
+	if (errctl & CP0_ERRCTL_ICACHE) {
+		printk(" c0_cerr_i   ==	  %08x", cerr_i);
+		breakout_cerri(cerr_i);
+		if (CP0_CERRI_IDX_VALID(cerr_i)) {
+			/* Check index of EPC, allowing for delay slot */
+			if (((eepc & SB1_CACHE_INDEX_MASK) != (cerr_i & SB1_CACHE_INDEX_MASK)) &&
+			    ((eepc & SB1_CACHE_INDEX_MASK) != ((cerr_i & SB1_CACHE_INDEX_MASK) - 4)))
+				printk(" cerr_i idx doesn't match eepc\n");
+			else {
+				res = extract_ic(cerr_i & SB1_CACHE_INDEX_MASK,
+						 (cerr_i & CP0_CERRI_DATA) != 0);
+				if (!(res & cerr_i))
+					printk("...didn't see indicated icache problem\n");
+			}
+		}
+	}
+	if (errctl & CP0_ERRCTL_DCACHE) {
+		printk(" c0_cerr_d   ==	  %08x", cerr_d);
+		breakout_cerrd(cerr_d);
+		if (CP0_CERRD_DPA_VALID(cerr_d)) {
+			printk(" c0_cerr_dpa == %010llx\n", cerr_dpa);
+			if (!CP0_CERRD_IDX_VALID(cerr_d)) {
+				res = extract_dc(cerr_dpa & SB1_CACHE_INDEX_MASK,
+						 (cerr_d & CP0_CERRD_DATA) != 0);
+				if (!(res & cerr_d))
+					printk("...didn't see indicated dcache problem\n");
+			} else {
+				if ((cerr_dpa & SB1_CACHE_INDEX_MASK) != (cerr_d & SB1_CACHE_INDEX_MASK))
+					printk(" cerr_d idx doesn't match cerr_dpa\n");
+				else {
+					res = extract_dc(cerr_d & SB1_CACHE_INDEX_MASK,
+							 (cerr_d & CP0_CERRD_DATA) != 0);
+					if (!(res & cerr_d))
+						printk("...didn't see indicated problem\n");
+				}
+			}
+		}
+	}
+
+	check_bus_watcher();
+
+	/*
+	 * Calling panic() when a fatal cache error occurs scrambles the
+	 * state of the system (and the cache), making it difficult to
+	 * investigate after the fact.	However, if you just stall the CPU,
+	 * the other CPU may keep on running, which is typically very
+	 * undesirable.
+	 */
+#ifdef CONFIG_SB1_CERR_STALL
+	while (1)
+		;
+#else
+	panic("unhandled cache error");
+#endif
+}
+
+
+/* Parity lookup table. */
+static const uint8_t parity[256] = {
+	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,
+	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,
+	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,
+	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,
+	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,
+	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,
+	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,
+	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
+};
+
+/* Masks to select bits for Hamming parity, mask_72_64[i] for bit[i] */
+static const uint64_t mask_72_64[8] = {
+	0x0738C808099264FFULL,
+	0x38C808099264FF07ULL,
+	0xC808099264FF0738ULL,
+	0x08099264FF0738C8ULL,
+	0x099264FF0738C808ULL,
+	0x9264FF0738C80809ULL,
+	0x64FF0738C8080992ULL,
+	0xFF0738C808099264ULL
+};
+
+/* Calculate the parity on a range of bits */
+static char range_parity(uint64_t dword, int max, int min)
+{
+	char parity = 0;
+	int i;
+	dword >>= min;
+	for (i=max-min; i>=0; i--) {
+		if (dword & 0x1)
+			parity = !parity;
+		dword >>= 1;
+	}
+	return parity;
+}
+
+/* Calculate the 4-bit even byte-parity for an instruction */
+static unsigned char inst_parity(uint32_t word)
+{
+	int i, j;
+	char parity = 0;
+	for (j=0; j<4; j++) {
+		char byte_parity = 0;
+		for (i=0; i<8; i++) {
+			if (word & 0x80000000)
+				byte_parity = !byte_parity;
+			word <<= 1;
+		}
+		parity <<= 1;
+		parity |= byte_parity;
+	}
+	return parity;
+}
+
+static uint32_t extract_ic(unsigned short addr, int data)
+{
+	unsigned short way;
+	int valid;
+	uint32_t taghi, taglolo, taglohi;
+	unsigned long long taglo, va;
+	uint64_t tlo_tmp;
+	uint8_t lru;
+	int res = 0;
+
+	printk("Icache index 0x%04x  ", addr);
+	for (way = 0; way < 4; way++) {
+		/* Index-load-tag-I */
+		__asm__ __volatile__ (
+		"	.set	push		\n\t"
+		"	.set	noreorder	\n\t"
+		"	.set	mips64		\n\t"
+		"	.set	noat		\n\t"
+		"	cache	4, 0(%3)	\n\t"
+		"	mfc0	%0, $29		\n\t"
+		"	dmfc0	$1, $28		\n\t"
+		"	dsrl32	%1, $1, 0	\n\t"
+		"	sll	%2, $1, 0	\n\t"
+		"	.set	pop"
+		: "=r" (taghi), "=r" (taglohi), "=r" (taglolo)
+		: "r" ((way << 13) | addr));
+
+		taglo = ((unsigned long long)taglohi << 32) | taglolo;
+		if (way == 0) {
+			lru = (taghi >> 14) & 0xff;
+			printk("[Bank %d Set 0x%02x]  LRU > %d %d %d %d > MRU\n",
+				    ((addr >> 5) & 0x3), /* bank */
+				    ((addr >> 7) & 0x3f), /* index */
+				    (lru & 0x3),
+				    ((lru >> 2) & 0x3),
+				    ((lru >> 4) & 0x3),
+				    ((lru >> 6) & 0x3));
+		}
+		va = (taglo & 0xC0000FFFFFFFE000ULL) | addr;
+		if ((taglo & (1 << 31)) && (((taglo >> 62) & 0x3) == 3))
+			va |= 0x3FFFF00000000000ULL;
+		valid = ((taghi >> 29) & 1);
+		if (valid) {
+			tlo_tmp = taglo & 0xfff3ff;
+			if (((taglo >> 10) & 1) ^ range_parity(tlo_tmp, 23, 0)) {
+				printk("   ** bad parity in VTag0/G/ASID\n");
+				res |= CP0_CERRI_TAG_PARITY;
+			}
+			if (((taglo >> 11) & 1) ^ range_parity(taglo, 63, 24)) {
+				printk("   ** bad parity in R/VTag1\n");
+				res |= CP0_CERRI_TAG_PARITY;
+			}
+		}
+		if (valid ^ ((taghi >> 27) & 1)) {
+			printk("   ** bad parity for valid bit\n");
+			res |= CP0_CERRI_TAG_PARITY;
+		}
+		printk(" %d  [VA %016llx]  [Vld? %d]  raw tags: %08X-%016llX\n",
+			    way, va, valid, taghi, taglo);
+
+		if (data) {
+			uint32_t datahi, insta, instb;
+			uint8_t predecode;
+			int offset;
+
+			/* (hit all banks and ways) */
+			for (offset = 0; offset < 4; offset++) {
+				/* Index-load-data-I */
+				__asm__ __volatile__ (
+				"	.set	push\n\t"
+				"	.set	noreorder\n\t"
+				"	.set	mips64\n\t"
+				"	.set	noat\n\t"
+				"	cache	6, 0(%3)  \n\t"
+				"	mfc0	%0, $29, 1\n\t"
+				"	dmfc0  $1, $28, 1\n\t"
+				"	dsrl32 %1, $1, 0 \n\t"
+				"	sll    %2, $1, 0 \n\t"
+				"	.set	pop	    \n"
+				: "=r" (datahi), "=r" (insta), "=r" (instb)
+				: "r" ((way << 13) | addr | (offset << 3)));
+				predecode = (datahi >> 8) & 0xff;
+				if (((datahi >> 16) & 1) != (uint32_t)range_parity(predecode, 7, 0)) {
+					printk("   ** bad parity in predecode\n");
+					res |= CP0_CERRI_DATA_PARITY;
+				}
+				/* XXXKW should/could check predecode bits themselves */
+				if (((datahi >> 4) & 0xf) ^ inst_parity(insta)) {
+					printk("   ** bad parity in instruction a\n");
+					res |= CP0_CERRI_DATA_PARITY;
+				}
+				if ((datahi & 0xf) ^ inst_parity(instb)) {
+					printk("   ** bad parity in instruction b\n");
+					res |= CP0_CERRI_DATA_PARITY;
+				}
+				printk("  %05X-%08X%08X", datahi, insta, instb);
+			}
+			printk("\n");
+		}
+	}
+	return res;
+}
+
+/* Compute the ECC for a data doubleword */
+static uint8_t dc_ecc(uint64_t dword)
+{
+	uint64_t t;
+	uint32_t w;
+	uint8_t	 p;
+	int	 i;
+
+	p = 0;
+	for (i = 7; i >= 0; i--)
+	{
+		p <<= 1;
+		t = dword & mask_72_64[i];
+		w = (uint32_t)(t >> 32);
+		p ^= (parity[w>>24] ^ parity[(w>>16) & 0xFF]
+		      ^ parity[(w>>8) & 0xFF] ^ parity[w & 0xFF]);
+		w = (uint32_t)(t & 0xFFFFFFFF);
+		p ^= (parity[w>>24] ^ parity[(w>>16) & 0xFF]
+		      ^ parity[(w>>8) & 0xFF] ^ parity[w & 0xFF]);
+	}
+	return p;
+}
+
+struct dc_state {
+	unsigned char val;
+	char *name;
+};
+
+static struct dc_state dc_states[] = {
+	{ 0x00, "INVALID" },
+	{ 0x0f, "COH-SHD" },
+	{ 0x13, "NCO-E-C" },
+	{ 0x19, "NCO-E-D" },
+	{ 0x16, "COH-E-C" },
+	{ 0x1c, "COH-E-D" },
+	{ 0xff, "*ERROR*" }
+};
+
+#define DC_TAG_VALID(state) \
+    (((state) == 0x0) || ((state) == 0xf) || ((state) == 0x13) || \
+     ((state) == 0x19) || ((state) == 0x16) || ((state) == 0x1c))
+
+static char *dc_state_str(unsigned char state)
+{
+	struct dc_state *dsc = dc_states;
+	while (dsc->val != 0xff) {
+		if (dsc->val == state)
+			break;
+		dsc++;
+	}
+	return dsc->name;
+}
+
+static uint32_t extract_dc(unsigned short addr, int data)
+{
+	int valid, way;
+	unsigned char state;
+	uint32_t taghi, taglolo, taglohi;
+	unsigned long long taglo, pa;
+	uint8_t ecc, lru;
+	int res = 0;
+
+	printk("Dcache index 0x%04x  ", addr);
+	for (way = 0; way < 4; way++) {
+		__asm__ __volatile__ (
+		"	.set	push\n\t"
+		"	.set	noreorder\n\t"
+		"	.set	mips64\n\t"
+		"	.set	noat\n\t"
+		"	cache	5, 0(%3)\n\t"	/* Index-load-tag-D */
+		"	mfc0	%0, $29, 2\n\t"
+		"	dmfc0	$1, $28, 2\n\t"
+		"	dsrl32	%1, $1, 0\n\t"
+		"	sll	%2, $1, 0\n\t"
+		"	.set	pop"
+		: "=r" (taghi), "=r" (taglohi), "=r" (taglolo)
+		: "r" ((way << 13) | addr));
+
+		taglo = ((unsigned long long)taglohi << 32) | taglolo;
+		pa = (taglo & 0xFFFFFFE000ULL) | addr;
+		if (way == 0) {
+			lru = (taghi >> 14) & 0xff;
+			printk("[Bank %d Set 0x%02x]  LRU > %d %d %d %d > MRU\n",
+				    ((addr >> 11) & 0x2) | ((addr >> 5) & 1), /* bank */
+				    ((addr >> 6) & 0x3f), /* index */
+				    (lru & 0x3),
+				    ((lru >> 2) & 0x3),
+				    ((lru >> 4) & 0x3),
+				    ((lru >> 6) & 0x3));
+		}
+		state = (taghi >> 25) & 0x1f;
+		valid = DC_TAG_VALID(state);
+		printk(" %d  [PA %010llx]  [state %s (%02x)]  raw tags: %08X-%016llX\n",
+			    way, pa, dc_state_str(state), state, taghi, taglo);
+		if (valid) {
+			if (((taglo >> 11) & 1) ^ range_parity(taglo, 39, 26)) {
+				printk("   ** bad parity in PTag1\n");
+				res |= CP0_CERRD_TAG_ADDRESS;
+			}
+			if (((taglo >> 10) & 1) ^ range_parity(taglo, 25, 13)) {
+				printk("   ** bad parity in PTag0\n");
+				res |= CP0_CERRD_TAG_ADDRESS;
+			}
+		} else {
+			res |= CP0_CERRD_TAG_STATE;
+		}
+
+		if (data) {
+			uint32_t datalohi, datalolo, datahi;
+			unsigned long long datalo;
+			int offset;
+			char bad_ecc = 0;
+
+			for (offset = 0; offset < 4; offset++) {
+				/* Index-load-data-D */
+				__asm__ __volatile__ (
+				"	.set	push\n\t"
+				"	.set	noreorder\n\t"
+				"	.set	mips64\n\t"
+				"	.set	noat\n\t"
+				"	cache	7, 0(%3)\n\t" /* Index-load-data-D */
+				"	mfc0	%0, $29, 3\n\t"
+				"	dmfc0	$1, $28, 3\n\t"
+				"	dsrl32	%1, $1, 0 \n\t"
+				"	sll	%2, $1, 0 \n\t"
+				"	.set	pop"
+				: "=r" (datahi), "=r" (datalohi), "=r" (datalolo)
+				: "r" ((way << 13) | addr | (offset << 3)));
+				datalo = ((unsigned long long)datalohi << 32) | datalolo;
+				ecc = dc_ecc(datalo);
+				if (ecc != datahi) {
+					int bits;
+					bad_ecc |= 1 << (3-offset);
+					ecc ^= datahi;
+					bits = hweight8(ecc);
+					res |= (bits == 1) ? CP0_CERRD_DATA_SBE : CP0_CERRD_DATA_DBE;
+				}
+				printk("  %02X-%016llX", datahi, datalo);
+			}
+			printk("\n");
+			if (bad_ecc)
+				printk("  dwords w/ bad ECC: %d %d %d %d\n",
+				       !!(bad_ecc & 8), !!(bad_ecc & 4),
+				       !!(bad_ecc & 2), !!(bad_ecc & 1));
+		}
+	}
+	return res;
+}