edac: Add an experimental new driver to support Sandy Bridge CPU's

This driver is known to work on mine and Tony's test environments,
using software error injection, and a partial hardware/software
error injection tool.

There's no broader range test yet to double check if the error decoding
logic will actually point to the right DIMM, so use it with care.
More tests are required to be sure that the driver will work on all
different types of memory configurations.

If you're willing to risk using it, I suggest you to enable EDAC debugs
for your test machines, as the debug logs helps to track what's going
inside the driver.

Please feed me with bug reports, if you notice that the driver
is miss-behaving.
Tested-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

drivers/edac/sb_edac.c

+/* Intel Sandy Bridge -EN/-EP/-EX Memory Controller kernel module
+ *
+ * This driver supports the memory controllers found on the Intel
+ * processor family Sandy Bridge.
+ *
+ * This file may be distributed under the terms of the
+ * GNU General Public License version 2 only.
+ *
+ * Copyright (c) 2011 by:
+ *	 Mauro Carvalho Chehab <mchehab@redhat.com>
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <linux/pci_ids.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/edac.h>
+#include <linux/mmzone.h>
+#include <linux/edac_mce.h>
+#include <linux/smp.h>
+#include <linux/bitmap.h>
+#include <asm/processor.h>
+
+#include "edac_core.h"
+
+/* Static vars */
+static LIST_HEAD(sbridge_edac_list);
+static DEFINE_MUTEX(sbridge_edac_lock);
+static int probed;
+
+/*
+ * Alter this version for the module when modifications are made
+ */
+#define SBRIDGE_REVISION    " Ver: 1.0.0 "
+#define EDAC_MOD_STR      "sbridge_edac"
+
+/*
+ * Debug macros
+ */
+#define sbridge_printk(level, fmt, arg...)			\
+	edac_printk(level, "sbridge", fmt, ##arg)
+
+#define sbridge_mc_printk(mci, level, fmt, arg...)		\
+	edac_mc_chipset_printk(mci, level, "sbridge", fmt, ##arg)
+
+/*
+ * Get a bit field at register value <v>, from bit <lo> to bit <hi>
+ */
+#define GET_BITFIELD(v, lo, hi)	\
+	(((v) & ((1ULL << ((hi) - (lo) + 1)) - 1) << (lo)) >> (lo))
+
+/*
+ * sbridge Memory Controller Registers
+ */
+
+/*
+ * FIXME: For now, let's order by device function, as it makes
+ * easier for driver's development proccess. This table should be
+ * moved to pci_id.h when submitted upstream
+ */
+#define PCI_DEVICE_ID_INTEL_SBRIDGE_SAD0	0x3cf4	/* 12.6 */
+#define PCI_DEVICE_ID_INTEL_SBRIDGE_SAD1	0x3cf6	/* 12.7 */
+#define PCI_DEVICE_ID_INTEL_SBRIDGE_BR		0x3cf5	/* 13.6 */
+#define PCI_DEVICE_ID_INTEL_SBRIDGE_IMC_HA0	0x3ca0	/* 14.0 */
+#define PCI_DEVICE_ID_INTEL_SBRIDGE_IMC_TA	0x3ca8	/* 15.0 */
+#define PCI_DEVICE_ID_INTEL_SBRIDGE_IMC_RAS	0x3c71	/* 15.1 */
+#define PCI_DEVICE_ID_INTEL_SBRIDGE_IMC_TAD0	0x3caa	/* 15.2 */
+#define PCI_DEVICE_ID_INTEL_SBRIDGE_IMC_TAD1	0x3cab	/* 15.3 */
+#define PCI_DEVICE_ID_INTEL_SBRIDGE_IMC_TAD2	0x3cac	/* 15.4 */
+#define PCI_DEVICE_ID_INTEL_SBRIDGE_IMC_TAD3	0x3cad	/* 15.5 */
+#define PCI_DEVICE_ID_INTEL_SBRIDGE_IMC_DDRIO	0x3cb8	/* 17.0 */
+
+	/*
+	 * Currently, unused, but will be needed in the future
+	 * implementations, as they hold the error counters
+	 */
+#define PCI_DEVICE_ID_INTEL_SBRIDGE_IMC_ERR0	0x3c72	/* 16.2 */
+#define PCI_DEVICE_ID_INTEL_SBRIDGE_IMC_ERR1	0x3c73	/* 16.3 */
+#define PCI_DEVICE_ID_INTEL_SBRIDGE_IMC_ERR2	0x3c76	/* 16.6 */
+#define PCI_DEVICE_ID_INTEL_SBRIDGE_IMC_ERR3	0x3c77	/* 16.7 */
+
+/* Devices 12 Function 6, Offsets 0x80 to 0xcc */
+static const u32 dram_rule[] = {
+	0x80, 0x88, 0x90, 0x98, 0xa0,
+	0xa8, 0xb0, 0xb8, 0xc0, 0xc8,
+};
+#define MAX_SAD		ARRAY_SIZE(dram_rule)
+
+#define SAD_LIMIT(reg)		((GET_BITFIELD(reg, 6, 25) << 26) | 0x3ffffff)
+#define DRAM_ATTR(reg)		GET_BITFIELD(reg, 2,  3)
+#define INTERLEAVE_MODE(reg)	GET_BITFIELD(reg, 1,  1)
+#define DRAM_RULE_ENABLE(reg)	GET_BITFIELD(reg, 0,  0)
+
+static char *get_dram_attr(u32 reg)
+{
+	switch(DRAM_ATTR(reg)) {
+		case 0:
+			return "DRAM";
+		case 1:
+			return "MMCFG";
+		case 2:
+			return "NXM";
+		default:
+			return "unknown";
+	}
+}
+
+static const u32 interleave_list[] = {
+	0x84, 0x8c, 0x94, 0x9c, 0xa4,
+	0xac, 0xb4, 0xbc, 0xc4, 0xcc,
+};
+#define MAX_INTERLEAVE	ARRAY_SIZE(interleave_list)
+
+#define SAD_PKG0(reg)		GET_BITFIELD(reg, 0, 2)
+#define SAD_PKG1(reg)		GET_BITFIELD(reg, 3, 5)
+#define SAD_PKG2(reg)		GET_BITFIELD(reg, 8, 10)
+#define SAD_PKG3(reg)		GET_BITFIELD(reg, 11, 13)
+#define SAD_PKG4(reg)		GET_BITFIELD(reg, 16, 18)
+#define SAD_PKG5(reg)		GET_BITFIELD(reg, 19, 21)
+#define SAD_PKG6(reg)		GET_BITFIELD(reg, 24, 26)
+#define SAD_PKG7(reg)		GET_BITFIELD(reg, 27, 29)
+
+static inline int sad_pkg(u32 reg, int interleave)
+{
+	switch (interleave) {
+	case 0:
+		return SAD_PKG0(reg);
+	case 1:
+		return SAD_PKG1(reg);
+	case 2:
+		return SAD_PKG2(reg);
+	case 3:
+		return SAD_PKG3(reg);
+	case 4:
+		return SAD_PKG4(reg);
+	case 5:
+		return SAD_PKG5(reg);
+	case 6:
+		return SAD_PKG6(reg);
+	case 7:
+		return SAD_PKG7(reg);
+	default:
+		return -EINVAL;
+	}
+}
+
+/* Devices 12 Function 7 */
+
+#define TOLM		0x80
+#define	TOHM		0x84
+
+#define GET_TOLM(reg)		((GET_BITFIELD(reg, 0,  3) << 28) | 0x3ffffff)
+#define GET_TOHM(reg)		((GET_BITFIELD(reg, 0, 20) << 25) | 0x3ffffff)
+
+/* Device 13 Function 6 */
+
+#define SAD_TARGET	0xf0
+
+#define SOURCE_ID(reg)		GET_BITFIELD(reg, 9, 11)
+
+#define SAD_CONTROL	0xf4
+
+#define NODE_ID(reg)		GET_BITFIELD(reg, 0, 2)
+
+/* Device 14 function 0 */
+
+static const u32 tad_dram_rule[] = {
+	0x40, 0x44, 0x48, 0x4c,
+	0x50, 0x54, 0x58, 0x5c,
+	0x60, 0x64, 0x68, 0x6c,
+};
+#define MAX_TAD	ARRAY_SIZE(tad_dram_rule)
+
+#define TAD_LIMIT(reg)		((GET_BITFIELD(reg, 12, 31) << 26) | 0x3ffffff)
+#define TAD_SOCK(reg)		GET_BITFIELD(reg, 10, 11)
+#define TAD_CH(reg)		GET_BITFIELD(reg,  8,  9)
+#define TAD_TGT3(reg)		GET_BITFIELD(reg,  6,  7)
+#define TAD_TGT2(reg)		GET_BITFIELD(reg,  4,  5)
+#define TAD_TGT1(reg)		GET_BITFIELD(reg,  2,  3)
+#define TAD_TGT0(reg)		GET_BITFIELD(reg,  0,  1)
+
+/* Device 15, function 0 */
+
+#define MCMTR			0x7c
+
+#define IS_ECC_ENABLED(mcmtr)		GET_BITFIELD(mcmtr, 2, 2)
+#define IS_LOCKSTEP_ENABLED(mcmtr)	GET_BITFIELD(mcmtr, 1, 1)
+#define IS_CLOSE_PG(mcmtr)		GET_BITFIELD(mcmtr, 0, 0)
+
+/* Device 15, function 1 */
+
+#define RASENABLES		0xac
+#define IS_MIRROR_ENABLED(reg)		GET_BITFIELD(reg, 0, 0)
+
+/* Device 15, functions 2-5 */
+
+static const int mtr_regs[] = {
+	0x80, 0x84, 0x88,
+};
+
+#define RANK_DISABLE(mtr)		GET_BITFIELD(mtr, 16, 19)
+#define IS_DIMM_PRESENT(mtr)		GET_BITFIELD(mtr, 14, 14)
+#define RANK_CNT_BITS(mtr)		GET_BITFIELD(mtr, 12, 13)
+#define RANK_WIDTH_BITS(mtr)		GET_BITFIELD(mtr, 2, 4)
+#define COL_WIDTH_BITS(mtr)		GET_BITFIELD(mtr, 0, 1)
+
+static const u32 tad_ch_nilv_offset[] = {
+	0x90, 0x94, 0x98, 0x9c,
+	0xa0, 0xa4, 0xa8, 0xac,
+	0xb0, 0xb4, 0xb8, 0xbc,
+};
+#define CHN_IDX_OFFSET(reg)		GET_BITFIELD(reg, 28, 29)
+#define TAD_OFFSET(reg)			(GET_BITFIELD(reg,  6, 25) << 26)
+
+static const u32 rir_way_limit[] = {
+	0x108, 0x10c, 0x110, 0x114, 0x118,
+};
+#define MAX_RIR_RANGES ARRAY_SIZE(rir_way_limit)
+
+#define IS_RIR_VALID(reg)	GET_BITFIELD(reg, 31, 31)
+#define RIR_WAY(reg)		GET_BITFIELD(reg, 28, 29)
+#define RIR_LIMIT(reg)		((GET_BITFIELD(reg,  1, 10) << 29)| 0x1fffffff)
+
+#define MAX_RIR_WAY	8
+
+static const u32 rir_offset[MAX_RIR_RANGES][MAX_RIR_WAY] = {
+	{ 0x120, 0x124, 0x128, 0x12c, 0x130, 0x134, 0x138, 0x13c },
+	{ 0x140, 0x144, 0x148, 0x14c, 0x150, 0x154, 0x158, 0x15c },
+	{ 0x160, 0x164, 0x168, 0x16c, 0x170, 0x174, 0x178, 0x17c },
+	{ 0x180, 0x184, 0x188, 0x18c, 0x190, 0x194, 0x198, 0x19c },
+	{ 0x1a0, 0x1a4, 0x1a8, 0x1ac, 0x1b0, 0x1b4, 0x1b8, 0x1bc },
+};
+
+#define RIR_RNK_TGT(reg)		GET_BITFIELD(reg, 16, 19)
+#define RIR_OFFSET(reg)		GET_BITFIELD(reg,  2, 14)
+
+/* Device 16, functions 2-7 */
+
+/*
+ * FIXME: Implement the error count reads directly
+ */
+
+static const u32 correrrcnt[] = {
+	0x104, 0x108, 0x10c, 0x110,
+};
+
+#define RANK_ODD_OV(reg)		GET_BITFIELD(reg, 31, 31)
+#define RANK_ODD_ERR_CNT(reg)		GET_BITFIELD(reg, 16, 30)
+#define RANK_EVEN_OV(reg)		GET_BITFIELD(reg, 15, 15)
+#define RANK_EVEN_ERR_CNT(reg)		GET_BITFIELD(reg,  0, 14)
+
+static const u32 correrrthrsld[] = {
+	0x11c, 0x120, 0x124, 0x128,
+};
+
+#define RANK_ODD_ERR_THRSLD(reg)	GET_BITFIELD(reg, 16, 30)
+#define RANK_EVEN_ERR_THRSLD(reg)	GET_BITFIELD(reg,  0, 14)
+
+
+/* Device 17, function 0 */
+
+#define RANK_CFG_A		0x0328
+
+#define IS_RDIMM_ENABLED(reg)		GET_BITFIELD(reg, 11, 11)
+
+/*
+ * sbridge structs
+ */
+
+#define NUM_CHANNELS	4
+#define MAX_DIMMS	3		/* Max DIMMS per channel */
+
+struct sbridge_info {
+	u32	mcmtr;
+};
+
+struct sbridge_channel {
+	u32		ranks;
+	u32		dimms;
+};
+
+struct pci_id_descr {
+	int			dev;
+	int			func;
+	int 			dev_id;
+	int			optional;
+};
+
+struct pci_id_table {
+	const struct pci_id_descr	*descr;
+	int				n_devs;
+};
+
+struct sbridge_dev {
+	struct list_head	list;
+	u8			bus, mc;
+	u8			node_id, source_id;
+	struct pci_dev		**pdev;
+	int			n_devs;
+	struct mem_ctl_info	*mci;
+};
+
+struct sbridge_pvt {
+	struct pci_dev		*pci_ta, *pci_ddrio, *pci_ras;
+	struct pci_dev		*pci_sad0, *pci_sad1, *pci_ha0;
+	struct pci_dev		*pci_br;
+	struct pci_dev		*pci_tad[NUM_CHANNELS];
+
+	struct sbridge_dev	*sbridge_dev;
+
+	struct sbridge_info	info;
+	struct sbridge_channel	channel[NUM_CHANNELS];
+
+	int 			csrow_map[NUM_CHANNELS][MAX_DIMMS];
+
+	/* Memory type detection */
+	bool			is_mirrored, is_lockstep, is_close_pg;
+
+	/* mcelog glue */
+	struct edac_mce		edac_mce;
+
+	/* Fifo double buffers */
+	struct mce		mce_entry[MCE_LOG_LEN];
+	struct mce		mce_outentry[MCE_LOG_LEN];
+
+	/* Fifo in/out counters */
+	unsigned		mce_in, mce_out;
+
+	/* Count indicator to show errors not got */
+	unsigned		mce_overrun;
+
+	/* Memory description */
+	u64			tolm, tohm;
+};
+
+#define PCI_DESCR(device, function, device_id)	\
+	.dev = (device),			\
+	.func = (function),			\
+	.dev_id = (device_id)
+
+static const struct pci_id_descr pci_dev_descr_sbridge[] = {
+		/* Processor Home Agent */
+	{ PCI_DESCR(14, 0, PCI_DEVICE_ID_INTEL_SBRIDGE_IMC_HA0)		},
+
+		/* Memory controller */
+	{ PCI_DESCR(15, 0, PCI_DEVICE_ID_INTEL_SBRIDGE_IMC_TA)		},
+	{ PCI_DESCR(15, 1, PCI_DEVICE_ID_INTEL_SBRIDGE_IMC_RAS)		},
+	{ PCI_DESCR(15, 2, PCI_DEVICE_ID_INTEL_SBRIDGE_IMC_TAD0)	},
+	{ PCI_DESCR(15, 3, PCI_DEVICE_ID_INTEL_SBRIDGE_IMC_TAD1)	},
+	{ PCI_DESCR(15, 4, PCI_DEVICE_ID_INTEL_SBRIDGE_IMC_TAD2)	},
+	{ PCI_DESCR(15, 5, PCI_DEVICE_ID_INTEL_SBRIDGE_IMC_TAD3)	},
+	{ PCI_DESCR(17, 0, PCI_DEVICE_ID_INTEL_SBRIDGE_IMC_DDRIO)	},
+
+		/* System Address Decoder */
+	{ PCI_DESCR(12, 6, PCI_DEVICE_ID_INTEL_SBRIDGE_SAD0)		},
+	{ PCI_DESCR(12, 7, PCI_DEVICE_ID_INTEL_SBRIDGE_SAD1)		},
+
+		/* Broadcast Registers */
+	{ PCI_DESCR(13, 6, PCI_DEVICE_ID_INTEL_SBRIDGE_BR)		},
+};
+
+#define PCI_ID_TABLE_ENTRY(A) { .descr=A, .n_devs = ARRAY_SIZE(A) }
+static const struct pci_id_table pci_dev_descr_sbridge_table[] = {
+	PCI_ID_TABLE_ENTRY(pci_dev_descr_sbridge),
+	{0,}			/* 0 terminated list. */
+};
+
+/*
+ *	pci_device_id	table for which devices we are looking for
+ */
+static const struct pci_device_id sbridge_pci_tbl[] __devinitdata = {
+	{PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_SBRIDGE_IMC_TA)},
+	{0,}			/* 0 terminated list. */
+};
+
+
+/****************************************************************************
+			Anciliary status routines
+ ****************************************************************************/
+
+static inline int numrank(u32 mtr)
+{
+	int ranks = (1 << RANK_CNT_BITS(mtr));
+
+	if (ranks > 4) {
+		debugf0("Invalid number of ranks: %d (max = 4) raw value = %x (%04x)",
+			ranks, (unsigned int)RANK_CNT_BITS(mtr), mtr);
+		return -EINVAL;
+	}
+
+	return ranks;
+}
+
+static inline int numrow(u32 mtr)
+{
+	int rows = (RANK_WIDTH_BITS(mtr) + 12);
+
+	if (rows < 13 || rows > 18) {
+		debugf0("Invalid number of rows: %d (should be between 14 and 17) raw value = %x (%04x)",
+			rows, (unsigned int)RANK_WIDTH_BITS(mtr), mtr);
+		return -EINVAL;
+	}
+
+	return 1 << rows;
+}
+
+static inline int numcol(u32 mtr)
+{
+	int cols = (COL_WIDTH_BITS(mtr) + 10);
+
+	if (cols > 12) {
+		debugf0("Invalid number of cols: %d (max = 4) raw value = %x (%04x)",
+			cols, (unsigned int)COL_WIDTH_BITS(mtr), mtr);
+		return -EINVAL;
+	}
+
+	return 1 << cols;
+}
+
+static struct sbridge_dev *get_sbridge_dev(u8 bus)
+{
+	struct sbridge_dev *sbridge_dev;
+
+	list_for_each_entry(sbridge_dev, &sbridge_edac_list, list) {
+		if (sbridge_dev->bus == bus)
+			return sbridge_dev;
+	}
+
+	return NULL;
+}
+
+static struct sbridge_dev *alloc_sbridge_dev(u8 bus,
+					   const struct pci_id_table *table)
+{
+	struct sbridge_dev *sbridge_dev;
+
+	sbridge_dev = kzalloc(sizeof(*sbridge_dev), GFP_KERNEL);
+	if (!sbridge_dev)
+		return NULL;
+
+	sbridge_dev->pdev = kzalloc(sizeof(*sbridge_dev->pdev) * table->n_devs,
+				   GFP_KERNEL);
+	if (!sbridge_dev->pdev) {
+		kfree(sbridge_dev);
+		return NULL;
+	}
+
+	sbridge_dev->bus = bus;
+	sbridge_dev->n_devs = table->n_devs;
+	list_add_tail(&sbridge_dev->list, &sbridge_edac_list);
+
+	return sbridge_dev;
+}
+
+static void free_sbridge_dev(struct sbridge_dev *sbridge_dev)
+{
+	list_del(&sbridge_dev->list);
+	kfree(sbridge_dev->pdev);
+	kfree(sbridge_dev);
+}
+
+/****************************************************************************
+			Memory check routines
+ ****************************************************************************/
+static struct pci_dev *get_pdev_slot_func(u8 bus, unsigned slot,
+					  unsigned func)
+{
+	struct sbridge_dev *sbridge_dev = get_sbridge_dev(bus);
+	int i;
+
+	if (!sbridge_dev)
+		return NULL;
+
+	for (i = 0; i < sbridge_dev->n_devs; i++) {
+		if (!sbridge_dev->pdev[i])
+			continue;
+
+		if (PCI_SLOT(sbridge_dev->pdev[i]->devfn) == slot &&
+		    PCI_FUNC(sbridge_dev->pdev[i]->devfn) == func) {
+			debugf1("Associated %02x.%02x.%d with %p\n",
+				bus, slot, func, sbridge_dev->pdev[i]);
+			return sbridge_dev->pdev[i];
+		}
+	}
+
+	return NULL;
+}
+
+/**
+ * sbridge_get_active_channels() - gets the number of channels and csrows
+ * bus:		Device bus
+ * @channels:	Number of channels that will be returned
+ * @csrows:	Number of csrows found
+ *
+ * Since EDAC core needs to know in advance the number of available channels
+ * and csrows, in order to allocate memory for csrows/channels, it is needed
+ * to run two similar steps. At the first step, implemented on this function,
+ * it checks the number of csrows/channels present at one socket, identified
+ * by the associated PCI bus.
+ * this is used in order to properly allocate the size of mci components.
+ * Note: one csrow is one dimm.
+ */
+static int sbridge_get_active_channels(const u8 bus, unsigned *channels,
+				      unsigned *csrows)
+{
+	struct pci_dev *pdev = NULL;
+	int i, j;
+	u32 mcmtr;
+
+	*channels = 0;
+	*csrows = 0;
+
+	pdev = get_pdev_slot_func(bus, 15, 0);
+	if (!pdev) {
+		sbridge_printk(KERN_ERR, "Couldn't find PCI device "
+					"%2x.%02d.%d!!!\n",
+					bus, 15, 0);
+		return -ENODEV;
+	}
+
+	pci_read_config_dword(pdev, MCMTR, &mcmtr);
+	if (!IS_ECC_ENABLED(mcmtr)) {
+		sbridge_printk(KERN_ERR, "ECC is disabled. Aborting\n");
+		return -ENODEV;
+	}
+
+	for (i = 0; i < NUM_CHANNELS; i++) {
+		u32 mtr;
+
+		/* Device 15 functions 2 - 5  */
+		pdev = get_pdev_slot_func(bus, 15, 2 + i);
+		if (!pdev) {
+			sbridge_printk(KERN_ERR, "Couldn't find PCI device "
+						 "%2x.%02d.%d!!!\n",
+						 bus, 15, 2 + i);
+			return -ENODEV;
+		}
+		(*channels)++;
+
+		for (j = 0; j < ARRAY_SIZE(mtr_regs); j++) {
+			pci_read_config_dword(pdev, mtr_regs[j], &mtr);
+			debugf1("Bus#%02x channel #%d  MTR%d = %x\n", bus, i, j, mtr);
+			if (IS_DIMM_PRESENT(mtr))
+				(*csrows)++;
+		}
+	}
+
+	debugf0("Number of active channels: %d, number of active dimms: %d\n",
+		*channels, *csrows);
+
+	return 0;
+}
+
+static int get_dimm_config(const struct mem_ctl_info *mci)
+{
+	struct sbridge_pvt *pvt = mci->pvt_info;
+	struct csrow_info *csr;
+	int i, j, banks, ranks, rows, cols, size, npages;
+	int csrow = 0;
+	unsigned long last_page = 0;
+	u32 reg;
+	enum edac_type mode;
+
+	pci_read_config_dword(pvt->pci_br, SAD_TARGET, &reg);
+	pvt->sbridge_dev->source_id = SOURCE_ID(reg);
+
+	pci_read_config_dword(pvt->pci_br, SAD_CONTROL, &reg);
+	pvt->sbridge_dev->node_id = NODE_ID(reg);
+	debugf0("mc#%d: Node ID: %d, source ID: %d\n",
+		pvt->sbridge_dev->mc,
+		pvt->sbridge_dev->node_id,
+		pvt->sbridge_dev->source_id);
+
+	pci_read_config_dword(pvt->pci_ras, RASENABLES, &reg);
+	if (IS_MIRROR_ENABLED(reg)) {
+		debugf0("Memory mirror is enabled\n");
+		pvt->is_mirrored = true;
+	} else {
+		debugf0("Memory mirror is disabled\n");
+		pvt->is_mirrored = false;
+	}
+
+	pci_read_config_dword(pvt->pci_ta, MCMTR, &pvt->info.mcmtr);
+	if (IS_LOCKSTEP_ENABLED(pvt->info.mcmtr)) {
+		debugf0("Lockstep is enabled\n");
+		mode = EDAC_S8ECD8ED;
+		pvt->is_lockstep = true;
+	} else {
+		debugf0("Lockstep is disabled\n");
+		mode = EDAC_S4ECD4ED;
+		pvt->is_lockstep = false;
+	}
+	if (IS_CLOSE_PG(pvt->info.mcmtr)) {
+		debugf0("address map is on closed page mode\n");
+		pvt->is_close_pg = true;
+	} else {
+		debugf0("address map is on open page mode\n");
+		pvt->is_close_pg = false;
+	}
+
+	pci_read_config_dword(pvt->pci_ta, RANK_CFG_A, &reg);
+	if (IS_RDIMM_ENABLED(reg)) {
+		/* FIXME: Can also be LRDIMM */
+		debugf0("Memory is registered\n");
+		mode = MEM_RDDR3;
+	} else {
+		debugf0("Memory is unregistered\n");
+		mode = MEM_DDR3;
+	}
+
+	/* On all supported DDR3 DIMM types, there are 8 banks available */
+	banks = 8;
+
+	for (i = 0; i < NUM_CHANNELS; i++) {
+		u32 mtr;
+
+		for (j = 0; j < ARRAY_SIZE(mtr_regs); j++) {
+			pci_read_config_dword(pvt->pci_tad[i],
+					      mtr_regs[j], &mtr);
+			debugf4("Channel #%d  MTR%d = %x\n", i, j, mtr);
+			if (IS_DIMM_PRESENT(mtr)) {
+				pvt->channel[i].dimms++;
+
+				ranks = numrank(mtr);
+				rows = numrow(mtr);
+				cols = numcol(mtr);
+
+				/* DDR3 has 8 I/O banks */
+				size = (rows * cols * banks * ranks) >> (20 - 3);
+				npages = MiB_TO_PAGES(size);
+
+				debugf0("mc#%d: channel %d, dimm %d, %d Mb (%d pages) bank: %d, rank: %d, row: %#x, col: %#x\n",
+					pvt->sbridge_dev->mc, i, j,
+					size, npages,
+					banks, ranks, rows, cols);
+				csr = &mci->csrows[csrow];
+
+				csr->first_page = last_page;
+				csr->last_page = last_page + npages - 1;
+				csr->page_mask = 0UL;	/* Unused */
+				csr->nr_pages = npages;
+				csr->grain = 32;
+				csr->csrow_idx = csrow;
+				csr->dtype = (banks == 8) ? DEV_X8 : DEV_X4;
+				csr->ce_count = 0;
+				csr->ue_count = 0;
+				csr->mtype = mode;
+				csr->edac_mode = mode;
+				csr->nr_channels = 1;
+				csr->channels[0].chan_idx = i;
+				csr->channels[0].ce_count = 0;
+				pvt->csrow_map[i][j] = csrow;
+				snprintf(csr->channels[0].label,
+					 sizeof(csr->channels[0].label),
+					 "CPU_SrcID#%u_Channel#%u_DIMM#%u",
+					 pvt->sbridge_dev->source_id, i, j);
+				last_page += npages;
+				csrow++;
+			}
+		}
+	}
+
+	return 0;
+}
+
+static void get_memory_layout(const struct mem_ctl_info *mci)
+{
+	struct sbridge_pvt *pvt = mci->pvt_info;
+	int i, j, k, n_sads, n_tads, sad_interl;
+	u32 reg;
+	u64 limit, prv = 0;
+	u64 tmp_mb;
+	u32 rir_way;
+
+	/*
+	 * Step 1) Get TOLM/TOHM ranges
+	 */
+
+	/* Address range is 32:28 */
+	pci_read_config_dword(pvt->pci_sad1, TOLM,
+			      &reg);
+	pvt->tolm = GET_TOLM(reg);
+	tmp_mb = (1 + pvt->tolm) >> 20;
+
+	debugf0("TOLM: %Lu.%03Lu GB (0x%016Lx)\n",
+		tmp_mb / 1000, tmp_mb % 1000, (u64)pvt->tolm);
+
+	/* Address range is already 45:25 */
+	pci_read_config_dword(pvt->pci_sad1, TOHM,
+			      &reg);
+	pvt->tohm = GET_TOHM(reg);
+	tmp_mb = (1 + pvt->tohm) >> 20;
+
+	debugf0("TOHM: %Lu.%03Lu GB (0x%016Lx)",
+		tmp_mb / 1000, tmp_mb % 1000, (u64)pvt->tohm);
+
+	/*
+	 * Step 2) Get SAD range and SAD Interleave list
+	 * TAD registers contain the interleave wayness. However, it
+	 * seems simpler to just discover it indirectly, with the
+	 * algorithm bellow.
+	 */
+	prv = 0;
+	for (n_sads = 0; n_sads < MAX_SAD; n_sads++) {
+		/* SAD_LIMIT Address range is 45:26 */
+		pci_read_config_dword(pvt->pci_sad0, dram_rule[n_sads],
+				      &reg);
+		limit = SAD_LIMIT(reg);
+
+		if (!DRAM_RULE_ENABLE(reg))
+			continue;
+
+		if (limit <= prv)
+			break;
+
+		tmp_mb = (limit + 1) >> 20;
+		debugf0("SAD#%d %s up to %Lu.%03Lu GB (0x%016Lx) %s reg=0x%08x\n",
+			n_sads,
+			get_dram_attr(reg),
+			tmp_mb / 1000, tmp_mb % 1000,
+			((u64)tmp_mb) << 20L,
+			INTERLEAVE_MODE(reg) ? "Interleave: 8:6" : "Interleave: [8:6]XOR[18:16]",
+			reg);
+		prv = limit;
+
+		pci_read_config_dword(pvt->pci_sad0, interleave_list[n_sads],
+				      &reg);
+		sad_interl = sad_pkg(reg, 0);
+		for (j = 0; j < 8; j++) {
+			if (j > 0 && sad_interl == sad_pkg(reg, j))
+				break;
+
+			debugf0("SAD#%d, interleave #%d: %d\n",
+			n_sads, j, sad_pkg(reg, j));
+		}
+	}
+
+	/*
+	 * Step 3) Get TAD range
+	 */
+	prv = 0;
+	for (n_tads = 0; n_tads < MAX_TAD; n_tads++) {
+		pci_read_config_dword(pvt->pci_ha0, tad_dram_rule[n_tads],
+				      &reg);
+		limit = TAD_LIMIT(reg);
+		if (limit <= prv)
+			break;
+		tmp_mb = (limit + 1) >> 20;
+
+		debugf0("TAD#%d: up to %Lu.%03Lu GB (0x%016Lx), socket interleave %d, memory interleave %d, TGT: %d, %d, %d, %d, reg=0x%08x\n",
+			n_tads, tmp_mb / 1000, tmp_mb % 1000,
+			((u64)tmp_mb) << 20L,
+			(u32)TAD_SOCK(reg),
+			(u32)TAD_CH(reg),
+			(u32)TAD_TGT0(reg),
+			(u32)TAD_TGT1(reg),
+			(u32)TAD_TGT2(reg),
+			(u32)TAD_TGT3(reg),
+			reg);
+		prv = tmp_mb;
+	}
+
+	/*
+	 * Step 4) Get TAD offsets, per each channel
+	 */
+	for (i = 0; i < NUM_CHANNELS; i++) {
+		if (!pvt->channel[i].dimms)
+			continue;
+		for (j = 0; j < n_tads; j++) {
+			pci_read_config_dword(pvt->pci_tad[i],
+					      tad_ch_nilv_offset[j],
+					      &reg);
+			tmp_mb = TAD_OFFSET(reg) >> 20;
+			debugf0("TAD CH#%d, offset #%d: %Lu.%03Lu GB (0x%016Lx), reg=0x%08x\n",
+				i, j,
+				tmp_mb / 1000, tmp_mb % 1000,
+				((u64)tmp_mb) << 20L,
+				reg);
+		}
+	}
+
+	/*
+	 * Step 6) Get RIR Wayness/Limit, per each channel
+	 */
+	for (i = 0; i < NUM_CHANNELS; i++) {
+		if (!pvt->channel[i].dimms)
+			continue;
+		for (j = 0; j < MAX_RIR_RANGES; j++) {
+			pci_read_config_dword(pvt->pci_tad[i],
+					      rir_way_limit[j],
+					      &reg);
+
+			if (!IS_RIR_VALID(reg))
+				continue;
+
+			tmp_mb = RIR_LIMIT(reg) >> 20;
+			rir_way = 1 << RIR_WAY(reg);
+			debugf0("CH#%d RIR#%d, limit: %Lu.%03Lu GB (0x%016Lx), way: %d, reg=0x%08x\n",
+				i, j,
+				tmp_mb / 1000, tmp_mb % 1000,
+				((u64)tmp_mb) << 20L,
+				rir_way,
+				reg);
+
+			for (k = 0; k < rir_way; k++) {
+				pci_read_config_dword(pvt->pci_tad[i],
+						      rir_offset[j][k],
+						      &reg);
+				tmp_mb = RIR_OFFSET(reg) << 6;
+
+				debugf0("CH#%d RIR#%d INTL#%d, offset %Lu.%03Lu GB (0x%016Lx), tgt: %d, reg=0x%08x\n",
+					i, j, k,
+					tmp_mb / 1000, tmp_mb % 1000,
+					((u64)tmp_mb) << 20L,
+					(u32)RIR_RNK_TGT(reg),
+					reg);
+			}
+		}
+	}
+}
+
+struct mem_ctl_info *get_mci_for_node_id(u8 node_id)
+{
+	struct sbridge_dev *sbridge_dev;
+
+	list_for_each_entry(sbridge_dev, &sbridge_edac_list, list) {
+		if (sbridge_dev->node_id == node_id)
+			return sbridge_dev->mci;
+	}
+	return NULL;
+}
+
+static int get_memory_error_data(struct mem_ctl_info *mci,
+				 u64 addr,
+				 u8 *socket,
+				 long *channel_mask,
+				 u8 *rank,
+				 char *area_type)
+{
+	struct mem_ctl_info	*new_mci;
+	struct sbridge_pvt *pvt = mci->pvt_info;
+	char			msg[256];
+	int 			n_rir, n_sads, n_tads, sad_way, sck_xch;
+	int			sad_interl, idx, base_ch;
+	int			interleave_mode;
+	unsigned		sad_interleave[MAX_INTERLEAVE];
+	u32			reg;
+	u8			ch_way,sck_way;
+	u32			tad_offset;
+	u32			rir_way;
+	u64			ch_addr, offset, limit, prv = 0;
+
+
+	/*
+	 * Step 0) Check if the address is at special memory ranges
+	 * The check bellow is probably enough to fill all cases where
+	 * the error is not inside a memory, except for the legacy
+	 * range (e. g. VGA addresses). It is unlikely, however, that the
+	 * memory controller would generate an error on that range.
+	 */
+	if ((addr > (u64) pvt->tolm) && (addr < (1L << 32))) {
+		sprintf(msg, "Error at TOLM area, on addr 0x%08Lx", addr);
+		edac_mc_handle_ce_no_info(mci, msg);
+		return -EINVAL;
+	}
+	if (addr >= (u64)pvt->tohm) {
+		sprintf(msg, "Error at MMIOH area, on addr 0x%016Lx", addr);
+		edac_mc_handle_ce_no_info(mci, msg);
+		return -EINVAL;
+	}
+
+	/*
+	 * Step 1) Get socket
+	 */
+	for (n_sads = 0; n_sads < MAX_SAD; n_sads++) {
+		pci_read_config_dword(pvt->pci_sad0, dram_rule[n_sads],
+				      &reg);
+
+		if (!DRAM_RULE_ENABLE(reg))
+			continue;
+
+		limit = SAD_LIMIT(reg);
+		if (limit <= prv) {
+			sprintf(msg, "Can't discover the memory socket");
+			edac_mc_handle_ce_no_info(mci, msg);
+			return -EINVAL;
+		}
+		if  (addr <= limit)
+			break;
+		prv = limit;
+	}
+	if (n_sads == MAX_SAD) {
+		sprintf(msg, "Can't discover the memory socket");
+		edac_mc_handle_ce_no_info(mci, msg);
+		return -EINVAL;
+	}
+	area_type = get_dram_attr(reg);
+	interleave_mode = INTERLEAVE_MODE(reg);
+
+	pci_read_config_dword(pvt->pci_sad0, interleave_list[n_sads],
+			      &reg);
+	sad_interl = sad_pkg(reg, 0);
+	for (sad_way = 0; sad_way < 8; sad_way++) {
+		if (sad_way > 0 && sad_interl == sad_pkg(reg, sad_way))
+			break;
+		sad_interleave[sad_way] = sad_pkg(reg, sad_way);
+		debugf0("SAD interleave #%d: %d\n",
+			sad_way, sad_interleave[sad_way]);
+	}
+	debugf0("mc#%d: Error detected on SAD#%d: address 0x%016Lx < 0x%016Lx, Interleave [%d:6]%s\n",
+		pvt->sbridge_dev->mc,
+		n_sads,
+		addr,
+		limit,
+		sad_way + 7,
+		INTERLEAVE_MODE(reg) ? "" : "XOR[18:16]");
+	if (interleave_mode)
+		idx = ((addr >> 6) ^ (addr >> 16)) & 7;
+	else
+		idx = (addr >> 6) & 7;
+	switch (sad_way) {
+	case 1:
+		idx = 0;
+		break;
+	case 2:
+		idx = idx & 1;
+		break;
+	case 4:
+		idx = idx & 3;
+		break;
+	case 8:
+		break;
+	default:
+		sprintf(msg, "Can't discover socket interleave");
+		edac_mc_handle_ce_no_info(mci, msg);
+		return -EINVAL;
+	}
+	*socket = sad_interleave[idx];
+	debugf0("SAD interleave index: %d (wayness %d) = CPU socket %d\n",
+		idx, sad_way, *socket);
+
+	/*
+	 * Move to the proper node structure, in order to access the
+	 * right PCI registers
+	 */
+	new_mci = get_mci_for_node_id(*socket);
+	if (!new_mci) {
+		sprintf(msg, "Struct for socket #%u wasn't initialized",
+			*socket);
+		edac_mc_handle_ce_no_info(mci, msg);
+		return -EINVAL;
+	}
+	mci = new_mci;
+	pvt = mci->pvt_info;
+
+	/*
+	 * Step 2) Get memory channel
+	 */
+	prv = 0;
+	for (n_tads = 0; n_tads < MAX_TAD; n_tads++) {
+		pci_read_config_dword(pvt->pci_ha0, tad_dram_rule[n_tads],
+				      &reg);
+		limit = TAD_LIMIT(reg);
+		if (limit <= prv) {
+			sprintf(msg, "Can't discover the memory channel");
+			edac_mc_handle_ce_no_info(mci, msg);
+			return -EINVAL;
+		}
+		if  (addr <= limit)
+			break;
+		prv = limit;
+	}
+	ch_way = TAD_CH(reg) + 1;
+	sck_way = TAD_SOCK(reg) + 1;
+	/*
+	 * FIXME: Is it right to always use channel 0 for offsets?
+	 */
+	pci_read_config_dword(pvt->pci_tad[0],
+				tad_ch_nilv_offset[n_tads],
+				&tad_offset);
+
+	if (ch_way == 3)
+		idx = addr >> 6;
+	else
+		idx = addr >> (6 + sck_way);
+	idx = idx % ch_way;
+
+	/*
+	 * FIXME: Shouldn't we use CHN_IDX_OFFSET() here, when ch_way == 3 ???
+	 */
+	switch (idx) {
+	case 0:
+		base_ch = TAD_TGT0(reg);
+		break;
+	case 1:
+		base_ch = TAD_TGT1(reg);
+		break;
+	case 2:
+		base_ch = TAD_TGT2(reg);
+		break;
+	case 3:
+		base_ch = TAD_TGT3(reg);
+		break;
+	default:
+		sprintf(msg, "Can't discover the TAD target");
+		edac_mc_handle_ce_no_info(mci, msg);
+		return -EINVAL;
+	}
+	*channel_mask = 1 << base_ch;
+
+	if (pvt->is_mirrored) {
+		*channel_mask |= 1 << ((base_ch + 2) % 4);
+		switch(ch_way) {
+		case 2:
+		case 4:
+			sck_xch = 1 << sck_way * (ch_way >> 1);
+			break;
+		default:
+			sprintf(msg, "Invalid mirror set. Can't decode addr");
+			edac_mc_handle_ce_no_info(mci, msg);
+			return -EINVAL;
+		}
+	} else
+		sck_xch = (1 << sck_way) * ch_way;
+
+	if (pvt->is_lockstep)
+		*channel_mask |= 1 << ((base_ch + 1) % 4);
+
+	offset = TAD_OFFSET(tad_offset);
+
+	debugf0("TAD#%d: address 0x%016Lx < 0x%016Lx, socket interleave %d, channel interleave %d (offset 0x%08Lx), index %d, base ch: %d, ch mask: 0x%02lx\n",
+		n_tads,
+		addr,
+		limit,
+		(u32)TAD_SOCK(reg),
+		ch_way,
+		offset,
+		idx,
+		base_ch,
+		*channel_mask);
+
+	/* Calculate channel address */
+	/* Remove the TAD offset */
+
+	if (offset > addr) {
+		sprintf(msg, "Can't calculate ch addr: TAD offset 0x%08Lx is too high for addr 0x%08Lx!",
+			offset, addr);
+		edac_mc_handle_ce_no_info(mci, msg);
+		return -EINVAL;
+	}
+	addr -= offset;
+	/* Store the low bits [0:6] of the addr */
+	ch_addr = addr & 0x7f;
+	/* Remove socket wayness and remove 6 bits */
+	addr >>= 6;
+	addr /= sck_xch;
+#if 0
+	/* Divide by channel way */
+	addr = addr / ch_way;
+#endif
+	/* Recover the last 6 bits */
+	ch_addr |= addr << 6;
+
+	/*
+	 * Step 3) Decode rank
+	 */
+	for (n_rir = 0; n_rir < MAX_RIR_RANGES; n_rir++) {
+		pci_read_config_dword(pvt->pci_tad[base_ch],
+				      rir_way_limit[n_rir],
+				      &reg);
+
+		if (!IS_RIR_VALID(reg))
+			continue;
+
+		limit = RIR_LIMIT(reg);
+
+		debugf0("RIR#%d, limit: %Lu.%03Lu GB (0x%016Lx), way: %d\n",
+			n_rir,
+			(limit >> 20) / 1000, (limit >> 20) % 1000,
+			limit,
+			1 << RIR_WAY(reg));
+		if  (ch_addr <= limit)
+			break;
+	}
+	if (n_rir == MAX_RIR_RANGES) {
+		sprintf(msg, "Can't discover the memory rank for ch addr 0x%08Lx",
+			ch_addr);
+		edac_mc_handle_ce_no_info(mci, msg);
+		return -EINVAL;
+	}
+	rir_way = RIR_WAY(reg);
+	if (pvt->is_close_pg)
+		idx = (ch_addr >> 6);
+	else
+		idx = (ch_addr >> 13);	/* FIXME: Datasheet says to shift by 15 */
+	idx %= 1 << rir_way;
+
+	pci_read_config_dword(pvt->pci_tad[base_ch],
+			      rir_offset[n_rir][idx],
+			      &reg);
+	*rank = RIR_RNK_TGT(reg);
+
+	debugf0("RIR#%d: channel address 0x%08Lx < 0x%08Lx, RIR interleave %d, index %d\n",
+		n_rir,
+		ch_addr,
+		limit,
+		rir_way,
+		idx);
+
+	return 0;
+}
+
+/****************************************************************************
+	Device initialization routines: put/get, init/exit
+ ****************************************************************************/
+
+/*
+ *	sbridge_put_all_devices	'put' all the devices that we have
+ *				reserved via 'get'
+ */
+static void sbridge_put_devices(struct sbridge_dev *sbridge_dev)
+{
+	int i;
+
+	debugf0(__FILE__ ": %s()\n", __func__);
+	for (i = 0; i < sbridge_dev->n_devs; i++) {
+		struct pci_dev *pdev = sbridge_dev->pdev[i];
+		if (!pdev)
+			continue;
+		debugf0("Removing dev %02x:%02x.%d\n",
+			pdev->bus->number,
+			PCI_SLOT(pdev->devfn), PCI_FUNC(pdev->devfn));
+		pci_dev_put(pdev);
+	}
+}
+
+static void sbridge_put_all_devices(void)
+{
+	struct sbridge_dev *sbridge_dev, *tmp;
+
+	list_for_each_entry_safe(sbridge_dev, tmp, &sbridge_edac_list, list) {
+		sbridge_put_devices(sbridge_dev);
+		free_sbridge_dev(sbridge_dev);
+	}
+}
+
+/*
+ *	sbridge_get_all_devices	Find and perform 'get' operation on the MCH's
+ *			device/functions we want to reference for this driver
+ *
+ *			Need to 'get' device 16 func 1 and func 2
+ */
+static int sbridge_get_onedevice(struct pci_dev **prev,
+				 u8 *num_mc,
+				 const struct pci_id_table *table,
+				 const unsigned devno)
+{
+	struct sbridge_dev *sbridge_dev;
+	const struct pci_id_descr *dev_descr = &table->descr[devno];
+
+	struct pci_dev *pdev = NULL;
+	u8 bus = 0;
+
+	sbridge_printk(KERN_INFO,
+		"Seeking for: dev %02x.%d PCI ID %04x:%04x\n",
+		dev_descr->dev, dev_descr->func,
+		PCI_VENDOR_ID_INTEL, dev_descr->dev_id);
+
+	pdev = pci_get_device(PCI_VENDOR_ID_INTEL,
+			      dev_descr->dev_id, *prev);
+
+	if (!pdev) {
+		if (*prev) {
+			*prev = pdev;
+			return 0;
+		}
+
+		if (dev_descr->optional)
+			return 0;
+
+		if (devno == 0)
+			return -ENODEV;
+
+		sbridge_printk(KERN_INFO,
+			"Device not found: dev %02x.%d PCI ID %04x:%04x\n",
+			dev_descr->dev, dev_descr->func,
+			PCI_VENDOR_ID_INTEL, dev_descr->dev_id);
+
+		/* End of list, leave */
+		return -ENODEV;
+	}
+	bus = pdev->bus->number;
+
+	sbridge_dev = get_sbridge_dev(bus);
+	if (!sbridge_dev) {
+		sbridge_dev = alloc_sbridge_dev(bus, table);
+		if (!sbridge_dev) {
+			pci_dev_put(pdev);
+			return -ENOMEM;
+		}
+		(*num_mc)++;
+	}
+
+	if (sbridge_dev->pdev[devno]) {
+		sbridge_printk(KERN_ERR,
+			"Duplicated device for "
+			"dev %02x:%d.%d PCI ID %04x:%04x\n",
+			bus, dev_descr->dev, dev_descr->func,
+			PCI_VENDOR_ID_INTEL, dev_descr->dev_id);
+		pci_dev_put(pdev);
+		return -ENODEV;
+	}
+
+	sbridge_dev->pdev[devno] = pdev;
+
+	/* Sanity check */
+	if (unlikely(PCI_SLOT(pdev->devfn) != dev_descr->dev ||
+			PCI_FUNC(pdev->devfn) != dev_descr->func)) {
+		sbridge_printk(KERN_ERR,
+			"Device PCI ID %04x:%04x "
+			"has dev %02x:%d.%d instead of dev %02x:%02x.%d\n",
+			PCI_VENDOR_ID_INTEL, dev_descr->dev_id,
+			bus, PCI_SLOT(pdev->devfn), PCI_FUNC(pdev->devfn),
+			bus, dev_descr->dev, dev_descr->func);
+		return -ENODEV;
+	}
+
+	/* Be sure that the device is enabled */
+	if (unlikely(pci_enable_device(pdev) < 0)) {
+		sbridge_printk(KERN_ERR,
+			"Couldn't enable "
+			"dev %02x:%d.%d PCI ID %04x:%04x\n",
+			bus, dev_descr->dev, dev_descr->func,
+			PCI_VENDOR_ID_INTEL, dev_descr->dev_id);
+		return -ENODEV;
+	}
+
+	debugf0("Detected dev %02x:%d.%d PCI ID %04x:%04x\n",
+		bus, dev_descr->dev,
+		dev_descr->func,
+		PCI_VENDOR_ID_INTEL, dev_descr->dev_id);
+
+	/*
+	 * As stated on drivers/pci/search.c, the reference count for
+	 * @from is always decremented if it is not %NULL. So, as we need
+	 * to get all devices up to null, we need to do a get for the device
+	 */
+	pci_dev_get(pdev);
+
+	*prev = pdev;
+
+	return 0;
+}
+
+static int sbridge_get_all_devices(u8 *num_mc)
+{
+	int i, rc;
+	struct pci_dev *pdev = NULL;
+	const struct pci_id_table *table = pci_dev_descr_sbridge_table;
+
+	while (table && table->descr) {
+		for (i = 0; i < table->n_devs; i++) {
+			pdev = NULL;
+			do {
+				rc = sbridge_get_onedevice(&pdev, num_mc,
+							   table, i);
+				if (rc < 0) {
+					if (i == 0) {
+						i = table->n_devs;
+						break;
+					}
+					sbridge_put_all_devices();
+					return -ENODEV;
+				}
+			} while (pdev);
+		}
+		table++;
+	}
+
+	return 0;
+}
+
+static int mci_bind_devs(struct mem_ctl_info *mci,
+			 struct sbridge_dev *sbridge_dev)
+{
+	struct sbridge_pvt *pvt = mci->pvt_info;
+	struct pci_dev *pdev;
+	int i, func, slot;
+
+	for (i = 0; i < sbridge_dev->n_devs; i++) {
+		pdev = sbridge_dev->pdev[i];
+		if (!pdev)
+			continue;
+		slot = PCI_SLOT(pdev->devfn);
+		func = PCI_FUNC(pdev->devfn);
+		switch (slot) {
+		case 12:
+			switch (func) {
+			case 6:
+				pvt->pci_sad0 = pdev;
+				break;
+			case 7:
+				pvt->pci_sad1 = pdev;
+				break;
+			default:
+				goto error;
+			}
+			break;
+		case 13:
+			switch (func) {
+			case 6:
+				pvt->pci_br = pdev;
+				break;
+			default:
+				goto error;
+			}
+			break;
+		case 14:
+			switch (func) {
+			case 0:
+				pvt->pci_ha0 = pdev;
+				break;
+			default:
+				goto error;
+			}
+			break;
+		case 15:
+			switch (func) {
+			case 0:
+				pvt->pci_ta = pdev;
+				break;
+			case 1:
+				pvt->pci_ras = pdev;
+				break;
+			case 2:
+			case 3:
+			case 4:
+			case 5:
+				pvt->pci_tad[func - 2] = pdev;
+				break;
+			default:
+				goto error;
+			}
+			break;
+		case 17:
+			switch (func) {
+			case 0:
+				pvt->pci_ddrio = pdev;
+				break;
+			default:
+				goto error;
+			}
+			break;
+		default:
+			goto error;
+		}
+
+		debugf0("Associated PCI %02x.%02d.%d with dev = %p\n",
+			sbridge_dev->bus,
+			PCI_SLOT(pdev->devfn), PCI_FUNC(pdev->devfn),
+			pdev);
+	}
+
+	/* Check if everything were registered */
+	if (!pvt->pci_sad0 || !pvt->pci_sad1 || !pvt->pci_ha0 ||
+	    !pvt-> pci_tad || !pvt->pci_ras  || !pvt->pci_ta ||
+	    !pvt->pci_ddrio)
+		goto enodev;
+
+	for (i = 0; i < NUM_CHANNELS; i++) {
+		if (!pvt->pci_tad[i])
+			goto enodev;
+	}
+	return 0;
+
+enodev:
+	sbridge_printk(KERN_ERR, "Some needed devices are missing\n");
+	return -ENODEV;
+
+error:
+	sbridge_printk(KERN_ERR, "Device %d, function %d "
+		      "is out of the expected range\n",
+		      slot, func);
+	return -EINVAL;
+}
+
+/****************************************************************************
+			Error check routines
+ ****************************************************************************/
+
+/*
+ * While Sandy Bridge has error count registers, SMI BIOS read values from
+ * and resets the counters. So, they are not reliable for the OS to read
+ * from them. So, we have no option but to just trust on whatever MCE is
+ * telling us about the errors.
+ */
+static void sbridge_mce_output_error(struct mem_ctl_info *mci,
+				    const struct mce *m)
+{
+	struct mem_ctl_info *new_mci;
+	struct sbridge_pvt *pvt = mci->pvt_info;
+	char *type, *optype, *msg, *recoverable_msg;
+	bool ripv = GET_BITFIELD(m->mcgstatus, 0, 0);
+	bool overflow = GET_BITFIELD(m->status, 62, 62);
+	bool uncorrected_error = GET_BITFIELD(m->status, 61, 61);
+	bool recoverable = GET_BITFIELD(m->status, 56, 56);
+	u32 core_err_cnt = GET_BITFIELD(m->status, 38, 52);
+	u32 mscod = GET_BITFIELD(m->status, 16, 31);
+	u32 errcode = GET_BITFIELD(m->status, 0, 15);
+	u32 channel = GET_BITFIELD(m->status, 0, 3);
+	u32 optypenum = GET_BITFIELD(m->status, 4, 6);
+	long channel_mask, first_channel;
+	u8  rank, socket;
+	int csrow, rc, dimm;
+	char *area_type = "Unknown";
+
+	if (ripv)
+		type = "NON_FATAL";
+	else
+		type = "FATAL";
+
+	/*
+	 * According with Table 15-9 of the Intel Archictecture spec vol 3A,
+	 * memory errors should fit in this mask:
+	 *	000f 0000 1mmm cccc (binary)
+	 * where:
+	 *	f = Correction Report Filtering Bit. If 1, subsequent errors
+	 *	    won't be shown
+	 *	mmm = error type
+	 *	cccc = channel
+	 * If the mask doesn't match, report an error to the parsing logic
+	 */
+	if (! ((errcode & 0xef80) == 0x80)) {
+		optype = "Can't parse: it is not a mem";
+	} else {
+		switch (optypenum) {
+		case 0:
+			optype = "generic undef request";
+			break;
+		case 1:
+			optype = "memory read";
+			break;
+		case 2:
+			optype = "memory write";
+			break;
+		case 3:
+			optype = "addr/cmd";
+			break;
+		case 4:
+			optype = "memory scrubbing";
+			break;
+		default:
+			optype = "reserved";
+			break;
+		}
+	}
+
+	rc = get_memory_error_data(mci, m->addr, &socket,
+				   &channel_mask, &rank, area_type);
+	if (rc < 0)
+		return;
+	new_mci = get_mci_for_node_id(socket);
+	if (!new_mci) {
+		edac_mc_handle_ce_no_info(mci, "Error: socket got corrupted!");
+		return;
+	}
+	mci = new_mci;
+	pvt = mci->pvt_info;
+
+	first_channel = find_first_bit(&channel_mask, NUM_CHANNELS);
+
+	if (rank < 4)
+		dimm = 0;
+	else if (rank < 8)
+		dimm = 1;
+	else
+		dimm = 2;
+
+	csrow = pvt->csrow_map[first_channel][dimm];
+
+	if (uncorrected_error && recoverable)
+		recoverable_msg = " recoverable";
+	else
+		recoverable_msg = "";
+
+	/*
+	 * FIXME: What should we do with "channel" information on mcelog?
+	 * Probably, we can just discard it, as the channel information
+	 * comes from the get_memory_error_data() address decoding
+	 */
+	msg = kasprintf(GFP_ATOMIC,
+			"%d %s error(s): %s on %s area %s%s: cpu=%d Err=%04x:%04x (ch=%d), "
+			"addr = 0x%08llx => socket=%d, Channel=%ld(mask=%ld), rank=%d\n",
+			core_err_cnt,
+			area_type,
+			optype,
+			type,
+			recoverable_msg,
+			overflow ? "OVERFLOW" : "",
+			m->cpu,
+			mscod, errcode,
+			channel,		/* 1111b means not specified */
+			(long long) m->addr,
+			socket,
+			first_channel,		/* This is the real channel on SB */
+			channel_mask,
+			rank);
+
+	debugf0("%s", msg);
+
+	/* Call the helper to output message */
+	if (uncorrected_error)
+		edac_mc_handle_fbd_ue(mci, csrow, 0, 0, msg);
+	else
+		edac_mc_handle_fbd_ce(mci, csrow, 0, msg);
+
+	kfree(msg);
+}
+
+/*
+ *	sbridge_check_error	Retrieve and process errors reported by the
+ *				hardware. Called by the Core module.
+ */
+static void sbridge_check_error(struct mem_ctl_info *mci)
+{
+	struct sbridge_pvt *pvt = mci->pvt_info;
+	int i;
+	unsigned count = 0;
+	struct mce *m;
+
+	/*
+	 * MCE first step: Copy all mce errors into a temporary buffer
+	 * We use a double buffering here, to reduce the risk of
+	 * loosing an error.
+	 */
+	smp_rmb();
+	count = (pvt->mce_out + MCE_LOG_LEN - pvt->mce_in)
+		% MCE_LOG_LEN;
+	if (!count)
+		return;
+
+	m = pvt->mce_outentry;
+	if (pvt->mce_in + count > MCE_LOG_LEN) {
+		unsigned l = MCE_LOG_LEN - pvt->mce_in;
+
+		memcpy(m, &pvt->mce_entry[pvt->mce_in], sizeof(*m) * l);
+		smp_wmb();
+		pvt->mce_in = 0;
+		count -= l;
+		m += l;
+	}
+	memcpy(m, &pvt->mce_entry[pvt->mce_in], sizeof(*m) * count);
+	smp_wmb();
+	pvt->mce_in += count;
+
+	smp_rmb();
+	if (pvt->mce_overrun) {
+		sbridge_printk(KERN_ERR, "Lost %d memory errors\n",
+			      pvt->mce_overrun);
+		smp_wmb();
+		pvt->mce_overrun = 0;
+	}
+
+	/*
+	 * MCE second step: parse errors and display
+	 */
+	for (i = 0; i < count; i++)
+		sbridge_mce_output_error(mci, &pvt->mce_outentry[i]);
+}
+
+/*
+ * sbridge_mce_check_error	Replicates mcelog routine to get errors
+ *				This routine simply queues mcelog errors, and
+ *				return. The error itself should be handled later
+ *				by sbridge_check_error.
+ * WARNING: As this routine should be called at NMI time, extra care should
+ * be taken to avoid deadlocks, and to be as fast as possible.
+ */
+static int sbridge_mce_check_error(void *priv, struct mce *mce)
+{
+	struct mem_ctl_info *mci = priv;
+	struct sbridge_pvt *pvt = mci->pvt_info;
+
+	/*
+	 * Just let mcelog handle it if the error is
+	 * outside the memory controller. A memory error
+	 * is indicated by bit 7 = 1 and bits = 8-11,13-15 = 0.
+	 * bit 12 has an special meaning.
+	 */
+	if ((mce->status & 0xefff) >> 7 != 1)
+		return 0;
+
+	printk("sbridge: HANDLING MCE MEMORY ERROR\n");
+
+	printk("CPU %d: Machine Check Exception: %Lx Bank %d: %016Lx\n",
+	       mce->extcpu, mce->mcgstatus, mce->bank, mce->status);
+	printk("TSC %llx ", mce->tsc);
+	printk("ADDR %llx ", mce->addr);
+	printk("MISC %llx ", mce->misc);
+
+	printk("PROCESSOR %u:%x TIME %llu SOCKET %u APIC %x\n",
+		mce->cpuvendor, mce->cpuid, mce->time,
+		mce->socketid, mce->apicid);
+
+#ifdef CONFIG_SMP
+	/* Only handle if it is the right mc controller */
+	if (cpu_data(mce->cpu).phys_proc_id != pvt->sbridge_dev->mc)
+		return 0;
+#endif
+
+	smp_rmb();
+	if ((pvt->mce_out + 1) % MCE_LOG_LEN == pvt->mce_in) {
+		smp_wmb();
+		pvt->mce_overrun++;
+		return 0;
+	}
+
+	/* Copy memory error at the ringbuffer */
+	memcpy(&pvt->mce_entry[pvt->mce_out], mce, sizeof(*mce));
+	smp_wmb();
+	pvt->mce_out = (pvt->mce_out + 1) % MCE_LOG_LEN;
+
+	/* Handle fatal errors immediately */
+	if (mce->mcgstatus & 1)
+		sbridge_check_error(mci);
+
+	/* Advice mcelog that the error were handled */
+	return 1;
+}
+
+/****************************************************************************
+			EDAC register/unregister logic
+ ****************************************************************************/
+
+static void sbridge_unregister_mci(struct sbridge_dev *sbridge_dev)
+{
+	struct mem_ctl_info *mci = sbridge_dev->mci;
+	struct sbridge_pvt *pvt;
+
+	if (unlikely(!mci || !mci->pvt_info)) {
+		debugf0("MC: " __FILE__ ": %s(): dev = %p\n",
+			__func__, &sbridge_dev->pdev[0]->dev);
+
+		sbridge_printk(KERN_ERR, "Couldn't find mci handler\n");
+		return;
+	}
+
+	pvt = mci->pvt_info;
+
+	debugf0("MC: " __FILE__ ": %s(): mci = %p, dev = %p\n",
+		__func__, mci, &sbridge_dev->pdev[0]->dev);
+
+	/* Disable MCE NMI handler */
+	edac_mce_unregister(&pvt->edac_mce);
+
+	/* Remove MC sysfs nodes */
+	edac_mc_del_mc(mci->dev);
+
+	debugf1("%s: free mci struct\n", mci->ctl_name);
+	kfree(mci->ctl_name);
+	edac_mc_free(mci);
+	sbridge_dev->mci = NULL;
+}
+
+static int sbridge_register_mci(struct sbridge_dev *sbridge_dev)
+{
+	struct mem_ctl_info *mci;
+	struct sbridge_pvt *pvt;
+	int rc, channels, csrows;
+
+	/* Check the number of active and not disabled channels */
+	rc = sbridge_get_active_channels(sbridge_dev->bus, &channels, &csrows);
+	if (unlikely(rc < 0))
+		return rc;
+
+	/* allocate a new MC control structure */
+	mci = edac_mc_alloc(sizeof(*pvt), csrows, channels, sbridge_dev->mc);
+	if (unlikely(!mci))
+		return -ENOMEM;
+
+	debugf0("MC: " __FILE__ ": %s(): mci = %p, dev = %p\n",
+		__func__, mci, &sbridge_dev->pdev[0]->dev);
+
+	pvt = mci->pvt_info;
+	memset(pvt, 0, sizeof(*pvt));
+
+	/* Associate sbridge_dev and mci for future usage */
+	pvt->sbridge_dev = sbridge_dev;
+	sbridge_dev->mci = mci;
+
+	mci->mtype_cap = MEM_FLAG_DDR3;
+	mci->edac_ctl_cap = EDAC_FLAG_NONE;
+	mci->edac_cap = EDAC_FLAG_NONE;
+	mci->mod_name = "sbridge_edac.c";
+	mci->mod_ver = SBRIDGE_REVISION;
+	mci->ctl_name = kasprintf(GFP_KERNEL, "Sandy Bridge Socket#%d", mci->mc_idx);
+	mci->dev_name = pci_name(sbridge_dev->pdev[0]);
+	mci->ctl_page_to_phys = NULL;
+
+	/* Set the function pointer to an actual operation function */
+	mci->edac_check = sbridge_check_error;
+
+	/* Store pci devices at mci for faster access */
+	rc = mci_bind_devs(mci, sbridge_dev);
+	if (unlikely(rc < 0))
+		goto fail0;
+
+	/* Get dimm basic config and the memory layout */
+	get_dimm_config(mci);
+	get_memory_layout(mci);
+
+	/* record ptr to the generic device */
+	mci->dev = &sbridge_dev->pdev[0]->dev;
+
+	/* add this new MC control structure to EDAC's list of MCs */
+	if (unlikely(edac_mc_add_mc(mci))) {
+		debugf0("MC: " __FILE__
+			": %s(): failed edac_mc_add_mc()\n", __func__);
+		rc = -EINVAL;
+		goto fail0;
+	}
+
+	/* Registers on edac_mce in order to receive memory errors */
+	pvt->edac_mce.priv = mci;
+	pvt->edac_mce.check_error = sbridge_mce_check_error;
+	rc = edac_mce_register(&pvt->edac_mce);
+	if (unlikely(rc < 0)) {
+		debugf0("MC: " __FILE__
+			": %s(): failed edac_mce_register()\n", __func__);
+		goto fail1;
+	}
+
+	return 0;
+fail1:
+	edac_mc_del_mc(mci->dev);
+
+fail0:
+	kfree(mci->ctl_name);
+	edac_mc_free(mci);
+	sbridge_dev->mci = NULL;
+	return rc;
+}
+
+/*
+ *	sbridge_probe	Probe for ONE instance of device to see if it is
+ *			present.
+ *	return:
+ *		0 for FOUND a device
+ *		< 0 for error code
+ */
+
+static int __devinit sbridge_probe(struct pci_dev *pdev,
+				  const struct pci_device_id *id)
+{
+	int rc;
+	u8 mc, num_mc = 0;
+	struct sbridge_dev *sbridge_dev;
+
+	/* get the pci devices we want to reserve for our use */
+	mutex_lock(&sbridge_edac_lock);
+
+	/*
+	 * All memory controllers are allocated at the first pass.
+	 */
+	if (unlikely(probed >= 1)) {
+		mutex_unlock(&sbridge_edac_lock);
+		return -ENODEV;
+	}
+	probed++;
+
+	rc = sbridge_get_all_devices(&num_mc);
+	if (unlikely(rc < 0))
+		goto fail0;
+	mc = 0;
+
+	list_for_each_entry(sbridge_dev, &sbridge_edac_list, list) {
+		debugf0("Registering MC#%d (%d of %d)\n", mc, mc + 1, num_mc);
+		sbridge_dev->mc = mc++;
+		rc = sbridge_register_mci(sbridge_dev);
+		if (unlikely(rc < 0))
+			goto fail1;
+	}
+
+	sbridge_printk(KERN_INFO, "Driver loaded.\n");
+
+	mutex_unlock(&sbridge_edac_lock);
+	return 0;
+
+fail1:
+	list_for_each_entry(sbridge_dev, &sbridge_edac_list, list)
+		sbridge_unregister_mci(sbridge_dev);
+
+	sbridge_put_all_devices();
+fail0:
+	mutex_unlock(&sbridge_edac_lock);
+	return rc;
+}
+
+/*
+ *	sbridge_remove	destructor for one instance of device
+ *
+ */
+static void __devexit sbridge_remove(struct pci_dev *pdev)
+{
+	struct sbridge_dev *sbridge_dev;
+
+	debugf0(__FILE__ ": %s()\n", __func__);
+
+	/*
+	 * we have a trouble here: pdev value for removal will be wrong, since
+	 * it will point to the X58 register used to detect that the machine
+	 * is a Nehalem or upper design. However, due to the way several PCI
+	 * devices are grouped together to provide MC functionality, we need
+	 * to use a different method for releasing the devices
+	 */
+
+	mutex_lock(&sbridge_edac_lock);
+
+	if (unlikely(!probed)) {
+		mutex_unlock(&sbridge_edac_lock);
+		return;
+	}
+
+	list_for_each_entry(sbridge_dev, &sbridge_edac_list, list)
+		sbridge_unregister_mci(sbridge_dev);
+
+	/* Release PCI resources */
+	sbridge_put_all_devices();
+
+	probed--;
+
+	mutex_unlock(&sbridge_edac_lock);
+}
+
+MODULE_DEVICE_TABLE(pci, sbridge_pci_tbl);
+
+/*
+ *	sbridge_driver	pci_driver structure for this module
+ *
+ */
+static struct pci_driver sbridge_driver = {
+	.name     = "sbridge_edac",
+	.probe    = sbridge_probe,
+	.remove   = __devexit_p(sbridge_remove),
+	.id_table = sbridge_pci_tbl,
+};
+
+/*
+ *	sbridge_init		Module entry function
+ *			Try to initialize this module for its devices
+ */
+static int __init sbridge_init(void)
+{
+	int pci_rc;
+
+	debugf2("MC: " __FILE__ ": %s()\n", __func__);
+
+	/* Ensure that the OPSTATE is set correctly for POLL or NMI */
+	opstate_init();
+
+	pci_rc = pci_register_driver(&sbridge_driver);
+
+	if (pci_rc >= 0)
+		return 0;
+
+	sbridge_printk(KERN_ERR, "Failed to register device with error %d.\n",
+		      pci_rc);
+
+	return pci_rc;
+}
+
+/*
+ *	sbridge_exit()	Module exit function
+ *			Unregister the driver
+ */
+static void __exit sbridge_exit(void)
+{
+	debugf2("MC: " __FILE__ ": %s()\n", __func__);
+	pci_unregister_driver(&sbridge_driver);
+}
+
+module_init(sbridge_init);
+module_exit(sbridge_exit);
+
+module_param(edac_op_state, int, 0444);
+MODULE_PARM_DESC(edac_op_state, "EDAC Error Reporting state: 0=Poll,1=NMI");
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@redhat.com>");
+MODULE_AUTHOR("Red Hat Inc. (http://www.redhat.com)");
+MODULE_DESCRIPTION("MC Driver for Intel Sandy Bridge memory controllers - "
+		   SBRIDGE_REVISION);