drivers/edac/i82975x_edac.c - kernel/msm-5.4 - Gitiles

 /*
  * Intel 82975X Memory Controller kernel module
  * (C) 2007 aCarLab (India) Pvt. Ltd. (http://acarlab.com)
  * (C) 2007 jetzbroadband (http://jetzbroadband.com)
  * This file may be distributed under the terms of the
  * GNU General Public License.
  *
  * Written by Arvind R.
  *   Copied from i82875p_edac.c source:
  */

 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/pci.h>
 #include <linux/pci_ids.h>
 #include <linux/edac.h>
 #include "edac_core.h"

 #define I82975X_REVISION	" Ver: 1.0.0"
 #define EDAC_MOD_STR		"i82975x_edac"

 #define i82975x_printk(level, fmt, arg...) \
 	edac_printk(level, "i82975x", fmt, ##arg)

 #define i82975x_mc_printk(mci, level, fmt, arg...) \
 	edac_mc_chipset_printk(mci, level, "i82975x", fmt, ##arg)

 #ifndef PCI_DEVICE_ID_INTEL_82975_0
 #define PCI_DEVICE_ID_INTEL_82975_0	0x277c
 #endif				/* PCI_DEVICE_ID_INTEL_82975_0 */

 #define I82975X_NR_CSROWS(nr_chans)		(8/(nr_chans))

 /* Intel 82975X register addresses - device 0 function 0 - DRAM Controller */
 #define I82975X_EAP		0x58	/* Dram Error Address Pointer (32b)
 					 *
 					 * 31:7  128 byte cache-line address
 					 * 6:1   reserved
 					 * 0     0: CH0; 1: CH1
 					 */

 #define I82975X_DERRSYN		0x5c	/* Dram Error SYNdrome (8b)
 					 *
 					 *  7:0  DRAM ECC Syndrome
 					 */

 #define I82975X_DES		0x5d	/* Dram ERRor DeSTination (8b)
 					 * 0h:    Processor Memory Reads
 					 * 1h:7h  reserved
 					 * More - See Page 65 of Intel DocSheet.
 					 */

 #define I82975X_ERRSTS		0xc8	/* Error Status Register (16b)
 					 *
 					 * 15:12 reserved
 					 * 11    Thermal Sensor Event
 					 * 10    reserved
 					 *  9    non-DRAM lock error (ndlock)
 					 *  8    Refresh Timeout
 					 *  7:2  reserved
 					 *  1    ECC UE (multibit DRAM error)
 					 *  0    ECC CE (singlebit DRAM error)
 					 */

 /* Error Reporting is supported by 3 mechanisms:
   1. DMI SERR generation  ( ERRCMD )
   2. SMI DMI  generation  ( SMICMD )
   3. SCI DMI  generation  ( SCICMD )
 NOTE: Only ONE of the three must be enabled
 */
 #define I82975X_ERRCMD		0xca	/* Error Command (16b)
 					 *
 					 * 15:12 reserved
 					 * 11    Thermal Sensor Event
 					 * 10    reserved
 					 *  9    non-DRAM lock error (ndlock)
 					 *  8    Refresh Timeout
 					 *  7:2  reserved
 					 *  1    ECC UE (multibit DRAM error)
 					 *  0    ECC CE (singlebit DRAM error)
 					 */

 #define I82975X_SMICMD		0xcc	/* Error Command (16b)
 					 *
 					 * 15:2  reserved
 					 *  1    ECC UE (multibit DRAM error)
 					 *  0    ECC CE (singlebit DRAM error)
 					 */

 #define I82975X_SCICMD		0xce	/* Error Command (16b)
 					 *
 					 * 15:2  reserved
 					 *  1    ECC UE (multibit DRAM error)
 					 *  0    ECC CE (singlebit DRAM error)
 					 */

 #define I82975X_XEAP	0xfc	/* Extended Dram Error Address Pointer (8b)
 					 *
 					 * 7:1   reserved
 					 * 0     Bit32 of the Dram Error Address
 					 */

 #define I82975X_MCHBAR		0x44	/*
 					 *
 					 * 31:14 Base Addr of 16K memory-mapped
 					 *	configuration space
 					 * 13:1  reserverd
 					 *  0    mem-mapped config space enable
 					 */

 /* NOTE: Following addresses have to indexed using MCHBAR offset (44h, 32b) */
 /* Intel 82975x memory mapped register space */

 #define I82975X_DRB_SHIFT 25	/* fixed 32MiB grain */

 #define I82975X_DRB		0x100	/* DRAM Row Boundary (8b x 8)
 					 *
 					 * 7   set to 1 in highest DRB of
 					 *	channel if 4GB in ch.
 					 * 6:2 upper boundary of rank in
 					 *	32MB grains
 					 * 1:0 set to 0
 					 */
 #define I82975X_DRB_CH0R0		0x100
 #define I82975X_DRB_CH0R1		0x101
 #define I82975X_DRB_CH0R2		0x102
 #define I82975X_DRB_CH0R3		0x103
 #define I82975X_DRB_CH1R0		0x180
 #define I82975X_DRB_CH1R1		0x181
 #define I82975X_DRB_CH1R2		0x182
 #define I82975X_DRB_CH1R3		0x183


 #define I82975X_DRA		0x108	/* DRAM Row Attribute (4b x 8)
 					 *  defines the PAGE SIZE to be used
 					 *	for the rank
 					 *  7    reserved
 					 *  6:4  row attr of odd rank, i.e. 1
 					 *  3    reserved
 					 *  2:0  row attr of even rank, i.e. 0
 					 *
 					 * 000 = unpopulated
 					 * 001 = reserved
 					 * 010 = 4KiB
 					 * 011 = 8KiB
 					 * 100 = 16KiB
 					 * others = reserved
 					 */
 #define I82975X_DRA_CH0R01		0x108
 #define I82975X_DRA_CH0R23		0x109
 #define I82975X_DRA_CH1R01		0x188
 #define I82975X_DRA_CH1R23		0x189


 #define I82975X_BNKARC	0x10e /* Type of device in each rank - Bank Arch (16b)
 					 *
 					 * 15:8  reserved
 					 * 7:6  Rank 3 architecture
 					 * 5:4  Rank 2 architecture
 					 * 3:2  Rank 1 architecture
 					 * 1:0  Rank 0 architecture
 					 *
 					 * 00 => 4 banks
 					 * 01 => 8 banks
 					 */
 #define I82975X_C0BNKARC	0x10e
 #define I82975X_C1BNKARC	0x18e


 #define I82975X_DRC		0x120 /* DRAM Controller Mode0 (32b)
 					 *
 					 * 31:30 reserved
 					 * 29    init complete
 					 * 28:11 reserved, according to Intel
 					 *    22:21 number of channels
 					 *		00=1 01=2 in 82875
 					 *		seems to be ECC mode
 					 *		bits in 82975 in Asus
 					 *		P5W
 					 *	 19:18 Data Integ Mode
 					 *		00=none 01=ECC in 82875
 					 * 10:8  refresh mode
 					 *  7    reserved
 					 *  6:4  mode select
 					 *  3:2  reserved
 					 *  1:0  DRAM type 10=Second Revision
 					 *		DDR2 SDRAM
 					 *         00, 01, 11 reserved
 					 */
 #define I82975X_DRC_CH0M0		0x120
 #define I82975X_DRC_CH1M0		0x1A0


 #define I82975X_DRC_M1	0x124 /* DRAM Controller Mode1 (32b)
 					 * 31	0=Standard Address Map
 					 *	1=Enhanced Address Map
 					 * 30:0	reserved
 					 */

 #define I82975X_DRC_CH0M1		0x124
 #define I82975X_DRC_CH1M1		0x1A4

 enum i82975x_chips {
 	I82975X = 0,
 };

 struct i82975x_pvt {
 	void __iomem *mch_window;
 };

 struct i82975x_dev_info {
 	const char *ctl_name;
 };

 struct i82975x_error_info {
 	u16 errsts;
 	u32 eap;
 	u8 des;
 	u8 derrsyn;
 	u16 errsts2;
 	u8 chan;		/* the channel is bit 0 of EAP */
 	u8 xeap;		/* extended eap bit */
 };

 static const struct i82975x_dev_info i82975x_devs[] = {
 	[I82975X] = {
 		.ctl_name = "i82975x"
 	},
 };

 static struct pci_dev *mci_pdev;	/* init dev: in case that AGP code has
 					 * already registered driver
 					 */

 static int i82975x_registered = 1;

 static void i82975x_get_error_info(struct mem_ctl_info *mci,
 		struct i82975x_error_info *info)
 {
 	struct pci_dev *pdev;

 	pdev = to_pci_dev(mci->dev);

 	/*
 	 * This is a mess because there is no atomic way to read all the
 	 * registers at once and the registers can transition from CE being
 	 * overwritten by UE.
 	 */
 	pci_read_config_word(pdev, I82975X_ERRSTS, &info->errsts);
 	pci_read_config_dword(pdev, I82975X_EAP, &info->eap);
 	pci_read_config_byte(pdev, I82975X_XEAP, &info->xeap);
 	pci_read_config_byte(pdev, I82975X_DES, &info->des);
 	pci_read_config_byte(pdev, I82975X_DERRSYN, &info->derrsyn);
 	pci_read_config_word(pdev, I82975X_ERRSTS, &info->errsts2);

 	pci_write_bits16(pdev, I82975X_ERRSTS, 0x0003, 0x0003);

 	/*
 	 * If the error is the same then we can for both reads then
 	 * the first set of reads is valid.  If there is a change then
 	 * there is a CE no info and the second set of reads is valid
 	 * and should be UE info.
 	 */
 	if (!(info->errsts2 & 0x0003))
 		return;

 	if ((info->errsts ^ info->errsts2) & 0x0003) {
 		pci_read_config_dword(pdev, I82975X_EAP, &info->eap);
 		pci_read_config_byte(pdev, I82975X_XEAP, &info->xeap);
 		pci_read_config_byte(pdev, I82975X_DES, &info->des);
 		pci_read_config_byte(pdev, I82975X_DERRSYN,
 				&info->derrsyn);
 	}
 }

 static int i82975x_process_error_info(struct mem_ctl_info *mci,
 		struct i82975x_error_info *info, int handle_errors)
 {
 	int row, chan;
 	unsigned long offst, page;

 	if (!(info->errsts2 & 0x0003))
 		return 0;

 	if (!handle_errors)
 		return 1;

 	if ((info->errsts ^ info->errsts2) & 0x0003) {
 		edac_mc_handle_ce_no_info(mci, "UE overwrote CE");
 		info->errsts = info->errsts2;
 	}

 	page = (unsigned long) info->eap;
 	page >>= 1;
 	if (info->xeap & 1)
 		page |= 0x80000000;
 	page >>= (PAGE_SHIFT - 1);
 	row = edac_mc_find_csrow_by_page(mci, page);

 	if (row == -1)	{
 		i82975x_mc_printk(mci, KERN_ERR, "error processing EAP:\n"
 			"\tXEAP=%u\n"
 			"\t EAP=0x%08x\n"
 			"\tPAGE=0x%08x\n",
 			(info->xeap & 1) ? 1 : 0, info->eap, (unsigned int) page);
 		return 0;
 	}
 	chan = (mci->csrows[row].nr_channels == 1) ? 0 : info->eap & 1;
 	offst = info->eap
 			& ((1 << PAGE_SHIFT) -
 				(1 << mci->csrows[row].grain));

 	if (info->errsts & 0x0002)
 		edac_mc_handle_ue(mci, page, offst , row, "i82975x UE");
 	else
 		edac_mc_handle_ce(mci, page, offst, info->derrsyn, row,
 				chan, "i82975x CE");

 	return 1;
 }

 static void i82975x_check(struct mem_ctl_info *mci)
 {
 	struct i82975x_error_info info;

 	debugf1("MC%d: %s()\n", mci->mc_idx, __func__);
 	i82975x_get_error_info(mci, &info);
 	i82975x_process_error_info(mci, &info, 1);
 }

 /* Return 1 if dual channel mode is active.  Else return 0. */
 static int dual_channel_active(void __iomem *mch_window)
 {
 	/*
 	 * We treat interleaved-symmetric configuration as dual-channel - EAP's
 	 * bit-0 giving the channel of the error location.
 	 *
 	 * All other configurations are treated as single channel - the EAP's
 	 * bit-0 will resolve ok in symmetric area of mixed
 	 * (symmetric/asymmetric) configurations
 	 */
 	u8	drb[4][2];
 	int	row;
 	int    dualch;

 	for (dualch = 1, row = 0; dualch && (row < 4); row++) {
 		drb[row][0] = readb(mch_window + I82975X_DRB + row);
 		drb[row][1] = readb(mch_window + I82975X_DRB + row + 0x80);
 		dualch = dualch && (drb[row][0] == drb[row][1]);
 	}
 	return dualch;
 }

 static enum dev_type i82975x_dram_type(void __iomem *mch_window, int rank)
 {
 	/*
 	 * ECC is possible on i92975x ONLY with DEV_X8
 	 */
 	return DEV_X8;
 }

 static void i82975x_init_csrows(struct mem_ctl_info *mci,
 		struct pci_dev *pdev, void __iomem *mch_window)
 {
 	static const char *labels[4] = {
 							"DIMM A1", "DIMM A2",
 							"DIMM B1", "DIMM B2"
 						};
 	struct csrow_info *csrow;
 	unsigned long last_cumul_size;
 	u8 value;
 	u32 cumul_size;
 	int index, chan;

 	last_cumul_size = 0;

 	/*
 	 * 82875 comment:
 	 * The dram row boundary (DRB) reg values are boundary address
 	 * for each DRAM row with a granularity of 32 or 64MB (single/dual
 	 * channel operation).  DRB regs are cumulative; therefore DRB7 will
 	 * contain the total memory contained in all rows.
 	 *
 	 */

 	for (index = 0; index < mci->nr_csrows; index++) {
 		csrow = &mci->csrows[index];

 		value = readb(mch_window + I82975X_DRB + index +
 					((index >= 4) ? 0x80 : 0));
 		cumul_size = value;
 		cumul_size <<= (I82975X_DRB_SHIFT - PAGE_SHIFT);
 		/*
 		 * Adjust cumul_size w.r.t number of channels
 		 *
 		 */
 		if (csrow->nr_channels > 1)
 			cumul_size <<= 1;
 		debugf3("%s(): (%d) cumul_size 0x%x\n", __func__, index,
 			cumul_size);

 		/*
 		 * Initialise dram labels
 		 * index values:
 		 *   [0-7] for single-channel; i.e. csrow->nr_channels = 1
 		 *   [0-3] for dual-channel; i.e. csrow->nr_channels = 2
 		 */
 		for (chan = 0; chan < csrow->nr_channels; chan++)
 			strncpy(csrow->channels[chan].dimm->label,
 					labels[(index >> 1) + (chan * 2)],
 					EDAC_MC_LABEL_LEN);

 		if (cumul_size == last_cumul_size)
 			continue;	/* not populated */

 		csrow->first_page = last_cumul_size;
 		csrow->last_page = cumul_size - 1;
 		csrow->nr_pages = cumul_size - last_cumul_size;
 		last_cumul_size = cumul_size;
 		csrow->grain = 1 << 7;	/* 128Byte cache-line resolution */
 		csrow->mtype = MEM_DDR2; /* I82975x supports only DDR2 */
 		csrow->dtype = i82975x_dram_type(mch_window, index);
 		csrow->edac_mode = EDAC_SECDED; /* only supported */
 	}
 }

 /* #define  i82975x_DEBUG_IOMEM */

 #ifdef i82975x_DEBUG_IOMEM
 static void i82975x_print_dram_timings(void __iomem *mch_window)
 {
 	/*
 	 * The register meanings are from Intel specs;
 	 * (shows 13-5-5-5 for 800-DDR2)
 	 * Asus P5W Bios reports 15-5-4-4
 	 * What's your religion?
 	 */
 	static const int caslats[4] = { 5, 4, 3, 6 };
 	u32	dtreg[2];

 	dtreg[0] = readl(mch_window + 0x114);
 	dtreg[1] = readl(mch_window + 0x194);
 	i82975x_printk(KERN_INFO, "DRAM Timings :     Ch0    Ch1\n"
 		"                RAS Active Min = %d     %d\n"
 		"                CAS latency    =  %d      %d\n"
 		"                RAS to CAS     =  %d      %d\n"
 		"                RAS precharge  =  %d      %d\n",
 		(dtreg[0] >> 19 ) & 0x0f,
 			(dtreg[1] >> 19) & 0x0f,
 		caslats[(dtreg[0] >> 8) & 0x03],
 			caslats[(dtreg[1] >> 8) & 0x03],
 		((dtreg[0] >> 4) & 0x07) + 2,
 			((dtreg[1] >> 4) & 0x07) + 2,
 		(dtreg[0] & 0x07) + 2,
 			(dtreg[1] & 0x07) + 2
 	);

 }
 #endif

 static int i82975x_probe1(struct pci_dev *pdev, int dev_idx)
 {
 	int rc = -ENODEV;
 	struct mem_ctl_info *mci;
 	struct i82975x_pvt *pvt;
 	void __iomem *mch_window;
 	u32 mchbar;
 	u32 drc[2];
 	struct i82975x_error_info discard;
 	int	chans;
 #ifdef i82975x_DEBUG_IOMEM
 	u8 c0drb[4];
 	u8 c1drb[4];
 #endif

 	debugf0("%s()\n", __func__);

 	pci_read_config_dword(pdev, I82975X_MCHBAR, &mchbar);
 	if (!(mchbar & 1)) {
 		debugf3("%s(): failed, MCHBAR disabled!\n", __func__);
 		goto fail0;
 	}
 	mchbar &= 0xffffc000;	/* bits 31:14 used for 16K window */
 	mch_window = ioremap_nocache(mchbar, 0x1000);

 #ifdef i82975x_DEBUG_IOMEM
 	i82975x_printk(KERN_INFO, "MCHBAR real = %0x, remapped = %p\n",
 					mchbar, mch_window);

 	c0drb[0] = readb(mch_window + I82975X_DRB_CH0R0);
 	c0drb[1] = readb(mch_window + I82975X_DRB_CH0R1);
 	c0drb[2] = readb(mch_window + I82975X_DRB_CH0R2);
 	c0drb[3] = readb(mch_window + I82975X_DRB_CH0R3);
 	c1drb[0] = readb(mch_window + I82975X_DRB_CH1R0);
 	c1drb[1] = readb(mch_window + I82975X_DRB_CH1R1);
 	c1drb[2] = readb(mch_window + I82975X_DRB_CH1R2);
 	c1drb[3] = readb(mch_window + I82975X_DRB_CH1R3);
 	i82975x_printk(KERN_INFO, "DRBCH0R0 = 0x%02x\n", c0drb[0]);
 	i82975x_printk(KERN_INFO, "DRBCH0R1 = 0x%02x\n", c0drb[1]);
 	i82975x_printk(KERN_INFO, "DRBCH0R2 = 0x%02x\n", c0drb[2]);
 	i82975x_printk(KERN_INFO, "DRBCH0R3 = 0x%02x\n", c0drb[3]);
 	i82975x_printk(KERN_INFO, "DRBCH1R0 = 0x%02x\n", c1drb[0]);
 	i82975x_printk(KERN_INFO, "DRBCH1R1 = 0x%02x\n", c1drb[1]);
 	i82975x_printk(KERN_INFO, "DRBCH1R2 = 0x%02x\n", c1drb[2]);
 	i82975x_printk(KERN_INFO, "DRBCH1R3 = 0x%02x\n", c1drb[3]);
 #endif

 	drc[0] = readl(mch_window + I82975X_DRC_CH0M0);
 	drc[1] = readl(mch_window + I82975X_DRC_CH1M0);
 #ifdef i82975x_DEBUG_IOMEM
 	i82975x_printk(KERN_INFO, "DRC_CH0 = %0x, %s\n", drc[0],
 			((drc[0] >> 21) & 3) == 1 ?
 				"ECC enabled" : "ECC disabled");
 	i82975x_printk(KERN_INFO, "DRC_CH1 = %0x, %s\n", drc[1],
 			((drc[1] >> 21) & 3) == 1 ?
 				"ECC enabled" : "ECC disabled");

 	i82975x_printk(KERN_INFO, "C0 BNKARC = %0x\n",
 		readw(mch_window + I82975X_C0BNKARC));
 	i82975x_printk(KERN_INFO, "C1 BNKARC = %0x\n",
 		readw(mch_window + I82975X_C1BNKARC));
 	i82975x_print_dram_timings(mch_window);
 	goto fail1;
 #endif
 	if (!(((drc[0] >> 21) & 3) == 1 || ((drc[1] >> 21) & 3) == 1)) {
 		i82975x_printk(KERN_INFO, "ECC disabled on both channels.\n");
 		goto fail1;
 	}

 	chans = dual_channel_active(mch_window) + 1;

 	/* assuming only one controller, index thus is 0 */
 	mci = edac_mc_alloc(sizeof(*pvt), I82975X_NR_CSROWS(chans),
 					chans, 0);
 	if (!mci) {
 		rc = -ENOMEM;
 		goto fail1;
 	}

 	debugf3("%s(): init mci\n", __func__);
 	mci->dev = &pdev->dev;
 	mci->mtype_cap = MEM_FLAG_DDR2;
 	mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_SECDED;
 	mci->edac_cap = EDAC_FLAG_NONE | EDAC_FLAG_SECDED;
 	mci->mod_name = EDAC_MOD_STR;
 	mci->mod_ver = I82975X_REVISION;
 	mci->ctl_name = i82975x_devs[dev_idx].ctl_name;
 	mci->dev_name = pci_name(pdev);
 	mci->edac_check = i82975x_check;
 	mci->ctl_page_to_phys = NULL;
 	debugf3("%s(): init pvt\n", __func__);
 	pvt = (struct i82975x_pvt *) mci->pvt_info;
 	pvt->mch_window = mch_window;
 	i82975x_init_csrows(mci, pdev, mch_window);
 	mci->scrub_mode = SCRUB_HW_SRC;
 	i82975x_get_error_info(mci, &discard);  /* clear counters */

 	/* finalize this instance of memory controller with edac core */
 	if (edac_mc_add_mc(mci)) {
 		debugf3("%s(): failed edac_mc_add_mc()\n", __func__);
 		goto fail2;
 	}

 	/* get this far and it's successful */
 	debugf3("%s(): success\n", __func__);
 	return 0;

 fail2:
 	edac_mc_free(mci);

 fail1:
 	iounmap(mch_window);
 fail0:
 	return rc;
 }

 /* returns count (>= 0), or negative on error */
 static int __devinit i82975x_init_one(struct pci_dev *pdev,
 		const struct pci_device_id *ent)
 {
 	int rc;

 	debugf0("%s()\n", __func__);

 	if (pci_enable_device(pdev) < 0)
 		return -EIO;

 	rc = i82975x_probe1(pdev, ent->driver_data);

 	if (mci_pdev == NULL)
 		mci_pdev = pci_dev_get(pdev);

 	return rc;
 }

 static void __devexit i82975x_remove_one(struct pci_dev *pdev)
 {
 	struct mem_ctl_info *mci;
 	struct i82975x_pvt *pvt;

 	debugf0("%s()\n", __func__);

 	mci = edac_mc_del_mc(&pdev->dev);
 	if (mci  == NULL)
 		return;

 	pvt = mci->pvt_info;
 	if (pvt->mch_window)
 		iounmap( pvt->mch_window );

 	edac_mc_free(mci);
 }

 static DEFINE_PCI_DEVICE_TABLE(i82975x_pci_tbl) = {
 	{
 		PCI_VEND_DEV(INTEL, 82975_0), PCI_ANY_ID, PCI_ANY_ID, 0, 0,
 		I82975X
 	},
 	{
 		0,
 	}	/* 0 terminated list. */
 };

 MODULE_DEVICE_TABLE(pci, i82975x_pci_tbl);

 static struct pci_driver i82975x_driver = {
 	.name = EDAC_MOD_STR,
 	.probe = i82975x_init_one,
 	.remove = __devexit_p(i82975x_remove_one),
 	.id_table = i82975x_pci_tbl,
 };

 static int __init i82975x_init(void)
 {
 	int pci_rc;

 	debugf3("%s()\n", __func__);

        /* Ensure that the OPSTATE is set correctly for POLL or NMI */
        opstate_init();

 	pci_rc = pci_register_driver(&i82975x_driver);
 	if (pci_rc < 0)
 		goto fail0;

 	if (mci_pdev == NULL) {
 		mci_pdev = pci_get_device(PCI_VENDOR_ID_INTEL,
 				PCI_DEVICE_ID_INTEL_82975_0, NULL);

 		if (!mci_pdev) {
 			debugf0("i82975x pci_get_device fail\n");
 			pci_rc = -ENODEV;
 			goto fail1;
 		}

 		pci_rc = i82975x_init_one(mci_pdev, i82975x_pci_tbl);

 		if (pci_rc < 0) {
 			debugf0("i82975x init fail\n");
 			pci_rc = -ENODEV;
 			goto fail1;
 		}
 	}

 	return 0;

 fail1:
 	pci_unregister_driver(&i82975x_driver);

 fail0:
 	if (mci_pdev != NULL)
 		pci_dev_put(mci_pdev);

 	return pci_rc;
 }

 static void __exit i82975x_exit(void)
 {
 	debugf3("%s()\n", __func__);

 	pci_unregister_driver(&i82975x_driver);

 	if (!i82975x_registered) {
 		i82975x_remove_one(mci_pdev);
 		pci_dev_put(mci_pdev);
 	}
 }

 module_init(i82975x_init);
 module_exit(i82975x_exit);

 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Arvind R. <arvino55@gmail.com>");
 MODULE_DESCRIPTION("MC support for Intel 82975 memory hub controllers");

 module_param(edac_op_state, int, 0444);
 MODULE_PARM_DESC(edac_op_state, "EDAC Error Reporting state: 0=Poll,1=NMI");
	/*
	* Intel 82975X Memory Controller kernel module
	* (C) 2007 aCarLab (India) Pvt. Ltd. (http://acarlab.com)
	* (C) 2007 jetzbroadband (http://jetzbroadband.com)
	* This file may be distributed under the terms of the
	* GNU General Public License.
	*
	* Written by Arvind R.
	* Copied from i82875p_edac.c source:
	*/

	#include <linux/module.h>
	#include <linux/init.h>
	#include <linux/pci.h>
	#include <linux/pci_ids.h>
	#include <linux/edac.h>
	#include "edac_core.h"

	#define I82975X_REVISION " Ver: 1.0.0"
	#define EDAC_MOD_STR "i82975x_edac"

	#define i82975x_printk(level, fmt, arg...) \
	edac_printk(level, "i82975x", fmt, ##arg)

	#define i82975x_mc_printk(mci, level, fmt, arg...) \
	edac_mc_chipset_printk(mci, level, "i82975x", fmt, ##arg)

	#ifndef PCI_DEVICE_ID_INTEL_82975_0
	#define PCI_DEVICE_ID_INTEL_82975_0 0x277c
	#endif /* PCI_DEVICE_ID_INTEL_82975_0 */

	#define I82975X_NR_CSROWS(nr_chans) (8/(nr_chans))

	/* Intel 82975X register addresses - device 0 function 0 - DRAM Controller */
	#define I82975X_EAP 0x58 /* Dram Error Address Pointer (32b)
	*
	* 31:7 128 byte cache-line address
	* 6:1 reserved
	* 0 0: CH0; 1: CH1
	*/

	#define I82975X_DERRSYN 0x5c /* Dram Error SYNdrome (8b)
	*
	* 7:0 DRAM ECC Syndrome
	*/

	#define I82975X_DES 0x5d /* Dram ERRor DeSTination (8b)
	* 0h: Processor Memory Reads
	* 1h:7h reserved
	* More - See Page 65 of Intel DocSheet.
	*/

	#define I82975X_ERRSTS 0xc8 /* Error Status Register (16b)
	*
	* 15:12 reserved
	* 11 Thermal Sensor Event
	* 10 reserved
	* 9 non-DRAM lock error (ndlock)
	* 8 Refresh Timeout
	* 7:2 reserved
	* 1 ECC UE (multibit DRAM error)
	* 0 ECC CE (singlebit DRAM error)
	*/

	/* Error Reporting is supported by 3 mechanisms:
	1. DMI SERR generation ( ERRCMD )
	2. SMI DMI generation ( SMICMD )
	3. SCI DMI generation ( SCICMD )
	NOTE: Only ONE of the three must be enabled
	*/
	#define I82975X_ERRCMD 0xca /* Error Command (16b)
	*
	* 15:12 reserved
	* 11 Thermal Sensor Event
	* 10 reserved
	* 9 non-DRAM lock error (ndlock)
	* 8 Refresh Timeout
	* 7:2 reserved
	* 1 ECC UE (multibit DRAM error)
	* 0 ECC CE (singlebit DRAM error)
	*/

	#define I82975X_SMICMD 0xcc /* Error Command (16b)
	*
	* 15:2 reserved
	* 1 ECC UE (multibit DRAM error)
	* 0 ECC CE (singlebit DRAM error)
	*/

	#define I82975X_SCICMD 0xce /* Error Command (16b)
	*
	* 15:2 reserved
	* 1 ECC UE (multibit DRAM error)
	* 0 ECC CE (singlebit DRAM error)
	*/

	#define I82975X_XEAP 0xfc /* Extended Dram Error Address Pointer (8b)
	*
	* 7:1 reserved
	* 0 Bit32 of the Dram Error Address
	*/

	#define I82975X_MCHBAR 0x44 /*
	*
	* 31:14 Base Addr of 16K memory-mapped
	* configuration space
	* 13:1 reserverd
	* 0 mem-mapped config space enable
	*/

	/* NOTE: Following addresses have to indexed using MCHBAR offset (44h, 32b) */
	/* Intel 82975x memory mapped register space */

	#define I82975X_DRB_SHIFT 25 /* fixed 32MiB grain */

	#define I82975X_DRB 0x100 /* DRAM Row Boundary (8b x 8)
	*
	* 7 set to 1 in highest DRB of
	* channel if 4GB in ch.
	* 6:2 upper boundary of rank in
	* 32MB grains
	* 1:0 set to 0
	*/
	#define I82975X_DRB_CH0R0 0x100
	#define I82975X_DRB_CH0R1 0x101
	#define I82975X_DRB_CH0R2 0x102
	#define I82975X_DRB_CH0R3 0x103
	#define I82975X_DRB_CH1R0 0x180
	#define I82975X_DRB_CH1R1 0x181
	#define I82975X_DRB_CH1R2 0x182
	#define I82975X_DRB_CH1R3 0x183


	#define I82975X_DRA 0x108 /* DRAM Row Attribute (4b x 8)
	* defines the PAGE SIZE to be used
	* for the rank
	* 7 reserved
	* 6:4 row attr of odd rank, i.e. 1
	* 3 reserved
	* 2:0 row attr of even rank, i.e. 0
	*
	* 000 = unpopulated
	* 001 = reserved
	* 010 = 4KiB
	* 011 = 8KiB
	* 100 = 16KiB
	* others = reserved
	*/
	#define I82975X_DRA_CH0R01 0x108
	#define I82975X_DRA_CH0R23 0x109
	#define I82975X_DRA_CH1R01 0x188
	#define I82975X_DRA_CH1R23 0x189


	#define I82975X_BNKARC 0x10e /* Type of device in each rank - Bank Arch (16b)
	*
	* 15:8 reserved
	* 7:6 Rank 3 architecture
	* 5:4 Rank 2 architecture
	* 3:2 Rank 1 architecture
	* 1:0 Rank 0 architecture
	*
	* 00 => 4 banks
	* 01 => 8 banks
	*/
	#define I82975X_C0BNKARC 0x10e
	#define I82975X_C1BNKARC 0x18e



	#define I82975X_DRC 0x120 /* DRAM Controller Mode0 (32b)
	*
	* 31:30 reserved
	* 29 init complete
	* 28:11 reserved, according to Intel
	* 22:21 number of channels
	* 00=1 01=2 in 82875
	* seems to be ECC mode
	* bits in 82975 in Asus
	* P5W
	* 19:18 Data Integ Mode
	* 00=none 01=ECC in 82875
	* 10:8 refresh mode
	* 7 reserved
	* 6:4 mode select
	* 3:2 reserved
	* 1:0 DRAM type 10=Second Revision
	* DDR2 SDRAM
	* 00, 01, 11 reserved
	*/
	#define I82975X_DRC_CH0M0 0x120
	#define I82975X_DRC_CH1M0 0x1A0


	#define I82975X_DRC_M1 0x124 /* DRAM Controller Mode1 (32b)
	* 31 0=Standard Address Map
	* 1=Enhanced Address Map
	* 30:0 reserved
	*/

	#define I82975X_DRC_CH0M1 0x124
	#define I82975X_DRC_CH1M1 0x1A4

	enum i82975x_chips {
	I82975X = 0,
	};

	struct i82975x_pvt {
	void __iomem *mch_window;
	};

	struct i82975x_dev_info {
	const char *ctl_name;
	};

	struct i82975x_error_info {
	u16 errsts;
	u32 eap;
	u8 des;
	u8 derrsyn;
	u16 errsts2;
	u8 chan; /* the channel is bit 0 of EAP */
	u8 xeap; /* extended eap bit */
	};

	static const struct i82975x_dev_info i82975x_devs[] = {
	[I82975X] = {
	.ctl_name = "i82975x"
	},
	};

	static struct pci_dev mci_pdev; / init dev: in case that AGP code has
	* already registered driver
	*/

	static int i82975x_registered = 1;

	static void i82975x_get_error_info(struct mem_ctl_info *mci,
	struct i82975x_error_info *info)
	{
	struct pci_dev *pdev;

	pdev = to_pci_dev(mci->dev);

	/*
	* This is a mess because there is no atomic way to read all the
	* registers at once and the registers can transition from CE being
	* overwritten by UE.
	*/
	pci_read_config_word(pdev, I82975X_ERRSTS, &info->errsts);
	pci_read_config_dword(pdev, I82975X_EAP, &info->eap);
	pci_read_config_byte(pdev, I82975X_XEAP, &info->xeap);
	pci_read_config_byte(pdev, I82975X_DES, &info->des);
	pci_read_config_byte(pdev, I82975X_DERRSYN, &info->derrsyn);
	pci_read_config_word(pdev, I82975X_ERRSTS, &info->errsts2);

	pci_write_bits16(pdev, I82975X_ERRSTS, 0x0003, 0x0003);

	/*
	* If the error is the same then we can for both reads then
	* the first set of reads is valid. If there is a change then
	* there is a CE no info and the second set of reads is valid
	* and should be UE info.
	*/
	if (!(info->errsts2 & 0x0003))
	return;

	if ((info->errsts ^ info->errsts2) & 0x0003) {
	pci_read_config_dword(pdev, I82975X_EAP, &info->eap);
	pci_read_config_byte(pdev, I82975X_XEAP, &info->xeap);
	pci_read_config_byte(pdev, I82975X_DES, &info->des);
	pci_read_config_byte(pdev, I82975X_DERRSYN,
	&info->derrsyn);
	}
	}

	static int i82975x_process_error_info(struct mem_ctl_info *mci,
	struct i82975x_error_info *info, int handle_errors)
	{
	int row, chan;
	unsigned long offst, page;

	if (!(info->errsts2 & 0x0003))
	return 0;

	if (!handle_errors)
	return 1;

	if ((info->errsts ^ info->errsts2) & 0x0003) {
	edac_mc_handle_ce_no_info(mci, "UE overwrote CE");
	info->errsts = info->errsts2;
	}

	page = (unsigned long) info->eap;
	page >>= 1;
	if (info->xeap & 1)
	page \|= 0x80000000;
	page >>= (PAGE_SHIFT - 1);
	row = edac_mc_find_csrow_by_page(mci, page);

	if (row == -1) {
	i82975x_mc_printk(mci, KERN_ERR, "error processing EAP:\n"
	"\tXEAP=%u\n"
	"\t EAP=0x%08x\n"
	"\tPAGE=0x%08x\n",
	(info->xeap & 1) ? 1 : 0, info->eap, (unsigned int) page);
	return 0;
	}
	chan = (mci->csrows[row].nr_channels == 1) ? 0 : info->eap & 1;
	offst = info->eap
	& ((1 << PAGE_SHIFT) -
	(1 << mci->csrows[row].grain));

	if (info->errsts & 0x0002)
	edac_mc_handle_ue(mci, page, offst , row, "i82975x UE");
	else
	edac_mc_handle_ce(mci, page, offst, info->derrsyn, row,
	chan, "i82975x CE");

	return 1;
	}

	static void i82975x_check(struct mem_ctl_info *mci)
	{
	struct i82975x_error_info info;

	debugf1("MC%d: %s()\n", mci->mc_idx, __func__);
	i82975x_get_error_info(mci, &info);
	i82975x_process_error_info(mci, &info, 1);
	}

	/* Return 1 if dual channel mode is active. Else return 0. */
	static int dual_channel_active(void __iomem *mch_window)
	{
	/*
	* We treat interleaved-symmetric configuration as dual-channel - EAP's
	* bit-0 giving the channel of the error location.
	*
	* All other configurations are treated as single channel - the EAP's
	* bit-0 will resolve ok in symmetric area of mixed
	* (symmetric/asymmetric) configurations
	*/
	u8 drb[4][2];
	int row;
	int dualch;

	for (dualch = 1, row = 0; dualch && (row < 4); row++) {
	drb[row][0] = readb(mch_window + I82975X_DRB + row);
	drb[row][1] = readb(mch_window + I82975X_DRB + row + 0x80);
	dualch = dualch && (drb[row][0] == drb[row][1]);
	}
	return dualch;
	}

	static enum dev_type i82975x_dram_type(void __iomem *mch_window, int rank)
	{
	/*
	* ECC is possible on i92975x ONLY with DEV_X8
	*/
	return DEV_X8;
	}

	static void i82975x_init_csrows(struct mem_ctl_info *mci,
	struct pci_dev pdev, void __iomem mch_window)
	{
	static const char *labels[4] = {
	"DIMM A1", "DIMM A2",
	"DIMM B1", "DIMM B2"
	};
	struct csrow_info *csrow;
	unsigned long last_cumul_size;
	u8 value;
	u32 cumul_size;
	int index, chan;

	last_cumul_size = 0;

	/*
	* 82875 comment:
	* The dram row boundary (DRB) reg values are boundary address
	* for each DRAM row with a granularity of 32 or 64MB (single/dual
	* channel operation). DRB regs are cumulative; therefore DRB7 will
	* contain the total memory contained in all rows.
	*
	*/

	for (index = 0; index < mci->nr_csrows; index++) {
	csrow = &mci->csrows[index];

	value = readb(mch_window + I82975X_DRB + index +
	((index >= 4) ? 0x80 : 0));
	cumul_size = value;
	cumul_size <<= (I82975X_DRB_SHIFT - PAGE_SHIFT);
	/*
	* Adjust cumul_size w.r.t number of channels
	*
	*/
	if (csrow->nr_channels > 1)
	cumul_size <<= 1;
	debugf3("%s(): (%d) cumul_size 0x%x\n", __func__, index,
	cumul_size);

	/*
	* Initialise dram labels
	* index values:
	* [0-7] for single-channel; i.e. csrow->nr_channels = 1
	* [0-3] for dual-channel; i.e. csrow->nr_channels = 2
	*/
	for (chan = 0; chan < csrow->nr_channels; chan++)
	strncpy(csrow->channels[chan].dimm->label,
	labels[(index >> 1) + (chan * 2)],
	EDAC_MC_LABEL_LEN);

	if (cumul_size == last_cumul_size)
	continue; /* not populated */

	csrow->first_page = last_cumul_size;
	csrow->last_page = cumul_size - 1;
	csrow->nr_pages = cumul_size - last_cumul_size;
	last_cumul_size = cumul_size;
	csrow->grain = 1 << 7; /* 128Byte cache-line resolution */
	csrow->mtype = MEM_DDR2; /* I82975x supports only DDR2 */
	csrow->dtype = i82975x_dram_type(mch_window, index);
	csrow->edac_mode = EDAC_SECDED; /* only supported */
	}
	}

	/* #define i82975x_DEBUG_IOMEM */

	#ifdef i82975x_DEBUG_IOMEM
	static void i82975x_print_dram_timings(void __iomem *mch_window)
	{
	/*
	* The register meanings are from Intel specs;
	* (shows 13-5-5-5 for 800-DDR2)
	* Asus P5W Bios reports 15-5-4-4
	* What's your religion?
	*/
	static const int caslats[4] = { 5, 4, 3, 6 };
	u32 dtreg[2];

	dtreg[0] = readl(mch_window + 0x114);
	dtreg[1] = readl(mch_window + 0x194);
	i82975x_printk(KERN_INFO, "DRAM Timings : Ch0 Ch1\n"
	" RAS Active Min = %d %d\n"
	" CAS latency = %d %d\n"
	" RAS to CAS = %d %d\n"
	" RAS precharge = %d %d\n",
	(dtreg[0] >> 19 ) & 0x0f,
	(dtreg[1] >> 19) & 0x0f,
	caslats[(dtreg[0] >> 8) & 0x03],
	caslats[(dtreg[1] >> 8) & 0x03],
	((dtreg[0] >> 4) & 0x07) + 2,
	((dtreg[1] >> 4) & 0x07) + 2,
	(dtreg[0] & 0x07) + 2,
	(dtreg[1] & 0x07) + 2
	);

	}
	#endif

	static int i82975x_probe1(struct pci_dev *pdev, int dev_idx)
	{
	int rc = -ENODEV;
	struct mem_ctl_info *mci;
	struct i82975x_pvt *pvt;
	void __iomem *mch_window;
	u32 mchbar;
	u32 drc[2];
	struct i82975x_error_info discard;
	int chans;
	#ifdef i82975x_DEBUG_IOMEM
	u8 c0drb[4];
	u8 c1drb[4];
	#endif

	debugf0("%s()\n", __func__);

	pci_read_config_dword(pdev, I82975X_MCHBAR, &mchbar);
	if (!(mchbar & 1)) {
	debugf3("%s(): failed, MCHBAR disabled!\n", __func__);
	goto fail0;
	}
	mchbar &= 0xffffc000; /* bits 31:14 used for 16K window */
	mch_window = ioremap_nocache(mchbar, 0x1000);

	#ifdef i82975x_DEBUG_IOMEM
	i82975x_printk(KERN_INFO, "MCHBAR real = %0x, remapped = %p\n",
	mchbar, mch_window);

	c0drb[0] = readb(mch_window + I82975X_DRB_CH0R0);
	c0drb[1] = readb(mch_window + I82975X_DRB_CH0R1);
	c0drb[2] = readb(mch_window + I82975X_DRB_CH0R2);
	c0drb[3] = readb(mch_window + I82975X_DRB_CH0R3);
	c1drb[0] = readb(mch_window + I82975X_DRB_CH1R0);
	c1drb[1] = readb(mch_window + I82975X_DRB_CH1R1);
	c1drb[2] = readb(mch_window + I82975X_DRB_CH1R2);
	c1drb[3] = readb(mch_window + I82975X_DRB_CH1R3);
	i82975x_printk(KERN_INFO, "DRBCH0R0 = 0x%02x\n", c0drb[0]);
	i82975x_printk(KERN_INFO, "DRBCH0R1 = 0x%02x\n", c0drb[1]);
	i82975x_printk(KERN_INFO, "DRBCH0R2 = 0x%02x\n", c0drb[2]);
	i82975x_printk(KERN_INFO, "DRBCH0R3 = 0x%02x\n", c0drb[3]);
	i82975x_printk(KERN_INFO, "DRBCH1R0 = 0x%02x\n", c1drb[0]);
	i82975x_printk(KERN_INFO, "DRBCH1R1 = 0x%02x\n", c1drb[1]);
	i82975x_printk(KERN_INFO, "DRBCH1R2 = 0x%02x\n", c1drb[2]);
	i82975x_printk(KERN_INFO, "DRBCH1R3 = 0x%02x\n", c1drb[3]);
	#endif

	drc[0] = readl(mch_window + I82975X_DRC_CH0M0);
	drc[1] = readl(mch_window + I82975X_DRC_CH1M0);
	#ifdef i82975x_DEBUG_IOMEM
	i82975x_printk(KERN_INFO, "DRC_CH0 = %0x, %s\n", drc[0],
	((drc[0] >> 21) & 3) == 1 ?
	"ECC enabled" : "ECC disabled");
	i82975x_printk(KERN_INFO, "DRC_CH1 = %0x, %s\n", drc[1],
	((drc[1] >> 21) & 3) == 1 ?
	"ECC enabled" : "ECC disabled");

	i82975x_printk(KERN_INFO, "C0 BNKARC = %0x\n",
	readw(mch_window + I82975X_C0BNKARC));
	i82975x_printk(KERN_INFO, "C1 BNKARC = %0x\n",
	readw(mch_window + I82975X_C1BNKARC));
	i82975x_print_dram_timings(mch_window);
	goto fail1;
	#endif
	if (!(((drc[0] >> 21) & 3) == 1 \|\| ((drc[1] >> 21) & 3) == 1)) {
	i82975x_printk(KERN_INFO, "ECC disabled on both channels.\n");
	goto fail1;
	}

	chans = dual_channel_active(mch_window) + 1;

	/* assuming only one controller, index thus is 0 */
	mci = edac_mc_alloc(sizeof(*pvt), I82975X_NR_CSROWS(chans),
	chans, 0);
	if (!mci) {
	rc = -ENOMEM;
	goto fail1;
	}

	debugf3("%s(): init mci\n", __func__);
	mci->dev = &pdev->dev;
	mci->mtype_cap = MEM_FLAG_DDR2;
	mci->edac_ctl_cap = EDAC_FLAG_NONE \| EDAC_FLAG_SECDED;
	mci->edac_cap = EDAC_FLAG_NONE \| EDAC_FLAG_SECDED;
	mci->mod_name = EDAC_MOD_STR;
	mci->mod_ver = I82975X_REVISION;
	mci->ctl_name = i82975x_devs[dev_idx].ctl_name;
	mci->dev_name = pci_name(pdev);
	mci->edac_check = i82975x_check;
	mci->ctl_page_to_phys = NULL;
	debugf3("%s(): init pvt\n", __func__);
	pvt = (struct i82975x_pvt *) mci->pvt_info;
	pvt->mch_window = mch_window;
	i82975x_init_csrows(mci, pdev, mch_window);
	mci->scrub_mode = SCRUB_HW_SRC;
	i82975x_get_error_info(mci, &discard); /* clear counters */

	/* finalize this instance of memory controller with edac core */
	if (edac_mc_add_mc(mci)) {
	debugf3("%s(): failed edac_mc_add_mc()\n", __func__);
	goto fail2;
	}

	/* get this far and it's successful */
	debugf3("%s(): success\n", __func__);
	return 0;

	fail2:
	edac_mc_free(mci);

	fail1:
	iounmap(mch_window);
	fail0:
	return rc;
	}

	/* returns count (>= 0), or negative on error */
	static int __devinit i82975x_init_one(struct pci_dev *pdev,
	const struct pci_device_id *ent)
	{
	int rc;

	debugf0("%s()\n", __func__);

	if (pci_enable_device(pdev) < 0)
	return -EIO;

	rc = i82975x_probe1(pdev, ent->driver_data);

	if (mci_pdev == NULL)
	mci_pdev = pci_dev_get(pdev);

	return rc;
	}

	static void __devexit i82975x_remove_one(struct pci_dev *pdev)
	{
	struct mem_ctl_info *mci;
	struct i82975x_pvt *pvt;

	debugf0("%s()\n", __func__);

	mci = edac_mc_del_mc(&pdev->dev);
	if (mci == NULL)
	return;

	pvt = mci->pvt_info;
	if (pvt->mch_window)
	iounmap( pvt->mch_window );

	edac_mc_free(mci);
	}

	static DEFINE_PCI_DEVICE_TABLE(i82975x_pci_tbl) = {
	{
	PCI_VEND_DEV(INTEL, 82975_0), PCI_ANY_ID, PCI_ANY_ID, 0, 0,
	I82975X
	},
	{
	0,
	} /* 0 terminated list. */
	};

	MODULE_DEVICE_TABLE(pci, i82975x_pci_tbl);

	static struct pci_driver i82975x_driver = {
	.name = EDAC_MOD_STR,
	.probe = i82975x_init_one,
	.remove = __devexit_p(i82975x_remove_one),
	.id_table = i82975x_pci_tbl,
	};

	static int __init i82975x_init(void)
	{
	int pci_rc;

	debugf3("%s()\n", __func__);

	/* Ensure that the OPSTATE is set correctly for POLL or NMI */
	opstate_init();

	pci_rc = pci_register_driver(&i82975x_driver);
	if (pci_rc < 0)
	goto fail0;

	if (mci_pdev == NULL) {
	mci_pdev = pci_get_device(PCI_VENDOR_ID_INTEL,
	PCI_DEVICE_ID_INTEL_82975_0, NULL);

	if (!mci_pdev) {
	debugf0("i82975x pci_get_device fail\n");
	pci_rc = -ENODEV;
	goto fail1;
	}

	pci_rc = i82975x_init_one(mci_pdev, i82975x_pci_tbl);

	if (pci_rc < 0) {
	debugf0("i82975x init fail\n");
	pci_rc = -ENODEV;
	goto fail1;
	}
	}

	return 0;

	fail1:
	pci_unregister_driver(&i82975x_driver);

	fail0:
	if (mci_pdev != NULL)
	pci_dev_put(mci_pdev);

	return pci_rc;
	}

	static void __exit i82975x_exit(void)
	{
	debugf3("%s()\n", __func__);

	pci_unregister_driver(&i82975x_driver);

	if (!i82975x_registered) {
	i82975x_remove_one(mci_pdev);
	pci_dev_put(mci_pdev);
	}
	}

	module_init(i82975x_init);
	module_exit(i82975x_exit);

	MODULE_LICENSE("GPL");
	MODULE_AUTHOR("Arvind R. <arvino55@gmail.com>");
	MODULE_DESCRIPTION("MC support for Intel 82975 memory hub controllers");

	module_param(edac_op_state, int, 0444);
	MODULE_PARM_DESC(edac_op_state, "EDAC Error Reporting state: 0=Poll,1=NMI");