/* 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/smp.h>
#include <linux/bitmap.h>
#include <linux/math64.h>
#include <asm/processor.h>
#include <asm/mce.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];

	/* Memory type detection */
	bool			is_mirrored, is_lockstep, is_close_pg;

	/* 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;
}

/**
 * check_if_ecc_is_active() - Checks if ECC is active
 * bus:		Device bus
 */
static int check_if_ecc_is_active(const u8 bus)
{
	struct pci_dev *pdev = NULL;
	u32 mcmtr;

	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;
	}
	return 0;
}

static int get_dimm_config(struct mem_ctl_info *mci)
{
	struct sbridge_pvt *pvt = mci->pvt_info;
	struct dimm_info *dimm;
	int i, j, banks, ranks, rows, cols, size, npages;
	u32 reg;
	enum edac_type mode;
	enum mem_type mtype;

	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");
		mtype = MEM_RDDR3;
	} else {
		debugf0("Memory is unregistered\n");
		mtype = 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++) {
			dimm = EDAC_DIMM_PTR(mci->layers, mci->dimms, mci->n_layers,
				       i, j, 0);
			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);

				dimm->nr_pages = npages;
				dimm->grain = 32;
				dimm->dtype = (banks == 8) ? DEV_X8 : DEV_X4;
				dimm->mtype = mtype;
				dimm->edac_mode = mode;
				snprintf(dimm->label, sizeof(dimm->label),
					 "CPU_SrcID#%u_Channel#%u_DIMM#%u",
					 pvt->sbridge_dev->source_id, i, j);
			}
		}
	}

	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 mb, kb;
	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;

	mb = div_u64_rem(tmp_mb, 1000, &kb);
	debugf0("TOLM: %u.%03u GB (0x%016Lx)\n",
		mb, kb, (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;

	mb = div_u64_rem(tmp_mb, 1000, &kb);
	debugf0("TOHM: %u.%03u GB (0x%016Lx)",
		mb, kb, (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;
		mb = div_u64_rem(tmp_mb, 1000, &kb);
		debugf0("SAD#%d %s up to %u.%03u GB (0x%016Lx) %s reg=0x%08x\n",
			n_sads,
			get_dram_attr(reg),
			mb, kb,
			((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;

		mb = div_u64_rem(tmp_mb, 1000, &kb);
		debugf0("TAD#%d: up to %u.%03u GB (0x%016Lx), socket interleave %d, memory interleave %d, TGT: %d, %d, %d, %d, reg=0x%08x\n",
			n_tads, mb, kb,
			((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 = limit;
	}

	/*
	 * 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;
			mb = div_u64_rem(tmp_mb, 1000, &kb);
			debugf0("TAD CH#%d, offset #%d: %u.%03u GB (0x%016Lx), reg=0x%08x\n",
				i, j,
				mb, kb,
				((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);
			mb = div_u64_rem(tmp_mb, 1000, &kb);
			debugf0("CH#%d RIR#%d, limit: %u.%03u GB (0x%016Lx), way: %d, reg=0x%08x\n",
				i, j,
				mb, kb,
				((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;

				mb = div_u64_rem(tmp_mb, 1000, &kb);
				debugf0("CH#%d RIR#%d INTL#%d, offset %u.%03u GB (0x%016Lx), tgt: %d, reg=0x%08x\n",
					i, j, k,
					mb, kb,
					((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, char *msg)
{
	struct mem_ctl_info	*new_mci;
	struct sbridge_pvt *pvt = mci->pvt_info;
	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;
	u32			mb, kb;
	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 < (1LL << 32))) {
		sprintf(msg, "Error at TOLM area, on addr 0x%08Lx", addr);
		return -EINVAL;
	}
	if (addr >= (u64)pvt->tohm) {
		sprintf(msg, "Error at MMIOH area, on addr 0x%016Lx", addr);
		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");
			return -EINVAL;
		}
		if  (addr <= limit)
			break;
		prv = limit;
	}
	if (n_sads == MAX_SAD) {
		sprintf(msg, "Can't discover the memory socket");
		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 ? "" : "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");
		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);
		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");
			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");
		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");
			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);
		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 = div_u64(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);
		mb = div_u64_rem(limit >> 20, 1000, &kb);
		debugf0("RIR#%d, limit: %u.%03u GB (0x%016Lx), way: %d\n",
			n_rir,
			mb, kb,
			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);
		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;
	enum hw_event_mc_err_type tp_event;
	char *type, *optype, msg[256], *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 rc, dimm;
	char *area_type = "Unknown";

	if (uncorrected_error) {
		if (ripv) {
			type = "FATAL";
			tp_event = HW_EVENT_ERR_FATAL;
		} else {
			type = "NON_FATAL";
			tp_event = HW_EVENT_ERR_UNCORRECTED;
		}
	} else {
		type = "CORRECTED";
		tp_event = HW_EVENT_ERR_CORRECTED;
	}

	/*
	 * 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 error";
			break;
		case 1:
			optype = "memory read error";
			break;
		case 2:
			optype = "memory write error";
			break;
		case 3:
			optype = "addr/cmd error";
			break;
		case 4:
			optype = "memory scrubbing error";
			break;
		default:
			optype = "reserved";
			break;
		}
	}

	rc = get_memory_error_data(mci, m->addr, &socket,
				   &channel_mask, &rank, area_type, msg);
	if (rc < 0)
		goto err_parsing;
	new_mci = get_mci_for_node_id(socket);
	if (!new_mci) {
		strcpy(msg, "Error: socket got corrupted!");
		goto err_parsing;
	}
	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;

	if (uncorrected_error && recoverable)
		recoverable_msg = " recoverable";
	else
		recoverable_msg = "";

	/*
	 * FIXME: On some memory configurations (mirror, lockstep), the
	 * Memory Controller can't point the error to a single DIMM. The
	 * EDAC core should be handling the channel mask, in order to point
	 * to the group of dimm's where the error may be happening.
	 */
	snprintf(msg, sizeof(msg),
		 "%d error(s)%s: %s%s: Err=%04x:%04x socket=%d channel=%ld/mask=%ld rank=%d",
		 core_err_cnt,
		 overflow ? " OVERFLOW" : "",
		 area_type,
		 recoverable_msg,
		 mscod, errcode,
		 socket,
		 first_channel,
		 channel_mask,
		 rank);

	debugf0("%s", msg);

	/* FIXME: need support for channel mask */

	/* Call the helper to output message */
	edac_mc_handle_error(tp_event, mci,
			     m->addr >> PAGE_SHIFT, m->addr & ~PAGE_MASK, 0,
			     channel, dimm, -1,
			     optype, msg, m);
	return;
err_parsing:
	edac_mc_handle_error(tp_event, mci, 0, 0, 0,
			     -1, -1, -1,
			     msg, "", m);

}

/*
 *	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(struct notifier_block *nb, unsigned long val,
				   void *data)
{
	struct mce *mce = (struct mce *)data;
	struct mem_ctl_info *mci;
	struct sbridge_pvt *pvt;

	mci = get_mci_for_node_id(mce->socketid);
	if (!mci)
		return NOTIFY_BAD;
	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 NOTIFY_DONE;

	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);

	/* Only handle if it is the right mc controller */
	if (cpu_data(mce->cpu).phys_proc_id != pvt->sbridge_dev->mc)
		return NOTIFY_DONE;

	smp_rmb();
	if ((pvt->mce_out + 1) % MCE_LOG_LEN == pvt->mce_in) {
		smp_wmb();
		pvt->mce_overrun++;
		return NOTIFY_DONE;
	}

	/* 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 NOTIFY_STOP;
}

static struct notifier_block sbridge_mce_dec = {
	.notifier_call      = sbridge_mce_check_error,
};

/****************************************************************************
			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);

	mce_unregister_decode_chain(&sbridge_mce_dec);

	/* Remove MC sysfs nodes */
	edac_mc_del_mc(mci->pdev);

	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 edac_mc_layer layers[2];
	struct sbridge_pvt *pvt;
	int rc;

	/* Check the number of active and not disabled channels */
	rc = check_if_ecc_is_active(sbridge_dev->bus);
	if (unlikely(rc < 0))
		return rc;

	/* allocate a new MC control structure */
	layers[0].type = EDAC_MC_LAYER_CHANNEL;
	layers[0].size = NUM_CHANNELS;
	layers[0].is_virt_csrow = false;
	layers[1].type = EDAC_MC_LAYER_SLOT;
	layers[1].size = MAX_DIMMS;
	layers[1].is_virt_csrow = true;
	mci = edac_mc_alloc(sbridge_dev->mc, ARRAY_SIZE(layers), layers,
			    false, sizeof(*pvt));

	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->pdev = &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;
	}

	mce_register_decode_chain(&sbridge_mce_dec);
	return 0;

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);