drivers/edac/x38_edac.c - kernel/msm-4.9 - Gitiles

 /*
  * Intel X38 Memory Controller kernel module
  * Copyright (C) 2008 Cluster Computing, Inc.
  *
  * This file may be distributed under the terms of the
  * GNU General Public License.
  *
  * This file is based on i3200_edac.c
  *
  */

 #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 X38_REVISION		"1.1"

 #define EDAC_MOD_STR		"x38_edac"

 #define PCI_DEVICE_ID_INTEL_X38_HB	0x29e0

 #define X38_RANKS		8
 #define X38_RANKS_PER_CHANNEL	4
 #define X38_CHANNELS		2

 /* Intel X38 register addresses - device 0 function 0 - DRAM Controller */

 #define X38_MCHBAR_LOW	0x48	/* MCH Memory Mapped Register BAR */
 #define X38_MCHBAR_HIGH	0x4c
 #define X38_MCHBAR_MASK	0xfffffc000ULL	/* bits 35:14 */
 #define X38_MMR_WINDOW_SIZE	16384

 #define X38_TOM	0xa0	/* Top of Memory (16b)
 				 *
 				 * 15:10 reserved
 				 *  9:0  total populated physical memory
 				 */
 #define X38_TOM_MASK	0x3ff	/* bits 9:0 */
 #define X38_TOM_SHIFT 26	/* 64MiB grain */

 #define X38_ERRSTS	0xc8	/* Error Status Register (16b)
 				 *
 				 * 15    reserved
 				 * 14    Isochronous TBWRR Run Behind FIFO Full
 				 *       (ITCV)
 				 * 13    Isochronous TBWRR Run Behind FIFO Put
 				 *       (ITSTV)
 				 * 12    reserved
 				 * 11    MCH Thermal Sensor Event
 				 *       for SMI/SCI/SERR (GTSE)
 				 * 10    reserved
 				 *  9    LOCK to non-DRAM Memory Flag (LCKF)
 				 *  8    reserved
 				 *  7    DRAM Throttle Flag (DTF)
 				 *  6:2  reserved
 				 *  1    Multi-bit DRAM ECC Error Flag (DMERR)
 				 *  0    Single-bit DRAM ECC Error Flag (DSERR)
 				 */
 #define X38_ERRSTS_UE		0x0002
 #define X38_ERRSTS_CE		0x0001
 #define X38_ERRSTS_BITS	(X38_ERRSTS_UE | X38_ERRSTS_CE)


 /* Intel  MMIO register space - device 0 function 0 - MMR space */

 #define X38_C0DRB	0x200	/* Channel 0 DRAM Rank Boundary (16b x 4)
 				 *
 				 * 15:10 reserved
 				 *  9:0  Channel 0 DRAM Rank Boundary Address
 				 */
 #define X38_C1DRB	0x600	/* Channel 1 DRAM Rank Boundary (16b x 4) */
 #define X38_DRB_MASK	0x3ff	/* bits 9:0 */
 #define X38_DRB_SHIFT 26	/* 64MiB grain */

 #define X38_C0ECCERRLOG 0x280	/* Channel 0 ECC Error Log (64b)
 				 *
 				 * 63:48 Error Column Address (ERRCOL)
 				 * 47:32 Error Row Address (ERRROW)
 				 * 31:29 Error Bank Address (ERRBANK)
 				 * 28:27 Error Rank Address (ERRRANK)
 				 * 26:24 reserved
 				 * 23:16 Error Syndrome (ERRSYND)
 				 * 15: 2 reserved
 				 *    1  Multiple Bit Error Status (MERRSTS)
 				 *    0  Correctable Error Status (CERRSTS)
 				 */
 #define X38_C1ECCERRLOG 0x680	/* Channel 1 ECC Error Log (64b) */
 #define X38_ECCERRLOG_CE	0x1
 #define X38_ECCERRLOG_UE	0x2
 #define X38_ECCERRLOG_RANK_BITS	0x18000000
 #define X38_ECCERRLOG_SYNDROME_BITS	0xff0000

 #define X38_CAPID0 0xe0	/* see P.94 of spec for details */

 static int x38_channel_num;

 static int how_many_channel(struct pci_dev *pdev)
 {
 	unsigned char capid0_8b; /* 8th byte of CAPID0 */

 	pci_read_config_byte(pdev, X38_CAPID0 + 8, &capid0_8b);
 	if (capid0_8b & 0x20) {	/* check DCD: Dual Channel Disable */
 		debugf0("In single channel mode.\n");
 		x38_channel_num = 1;
 	} else {
 		debugf0("In dual channel mode.\n");
 		x38_channel_num = 2;
 	}

 	return x38_channel_num;
 }

 static unsigned long eccerrlog_syndrome(u64 log)
 {
 	return (log & X38_ECCERRLOG_SYNDROME_BITS) >> 16;
 }

 static int eccerrlog_row(int channel, u64 log)
 {
 	return ((log & X38_ECCERRLOG_RANK_BITS) >> 27) |
 		(channel * X38_RANKS_PER_CHANNEL);
 }

 enum x38_chips {
 	X38 = 0,
 };

 struct x38_dev_info {
 	const char *ctl_name;
 };

 struct x38_error_info {
 	u16 errsts;
 	u16 errsts2;
 	u64 eccerrlog[X38_CHANNELS];
 };

 static const struct x38_dev_info x38_devs[] = {
 	[X38] = {
 		.ctl_name = "x38"},
 };

 static struct pci_dev *mci_pdev;
 static int x38_registered = 1;


 static void x38_clear_error_info(struct mem_ctl_info *mci)
 {
 	struct pci_dev *pdev;

 	pdev = to_pci_dev(mci->dev);

 	/*
 	 * Clear any error bits.
 	 * (Yes, we really clear bits by writing 1 to them.)
 	 */
 	pci_write_bits16(pdev, X38_ERRSTS, X38_ERRSTS_BITS,
 			 X38_ERRSTS_BITS);
 }

 static u64 x38_readq(const void __iomem *addr)
 {
 	return readl(addr) | (((u64)readl(addr + 4)) << 32);
 }

 static void x38_get_and_clear_error_info(struct mem_ctl_info *mci,
 				 struct x38_error_info *info)
 {
 	struct pci_dev *pdev;
 	void __iomem *window = mci->pvt_info;

 	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, X38_ERRSTS, &info->errsts);
 	if (!(info->errsts & X38_ERRSTS_BITS))
 		return;

 	info->eccerrlog[0] = x38_readq(window + X38_C0ECCERRLOG);
 	if (x38_channel_num == 2)
 		info->eccerrlog[1] = x38_readq(window + X38_C1ECCERRLOG);

 	pci_read_config_word(pdev, X38_ERRSTS, &info->errsts2);

 	/*
 	 * If the error is the same for both reads then the first set
 	 * of reads is valid.  If there is a change then there is a CE
 	 * with no info and the second set of reads is valid and
 	 * should be UE info.
 	 */
 	if ((info->errsts ^ info->errsts2) & X38_ERRSTS_BITS) {
 		info->eccerrlog[0] = x38_readq(window + X38_C0ECCERRLOG);
 		if (x38_channel_num == 2)
 			info->eccerrlog[1] =
 				x38_readq(window + X38_C1ECCERRLOG);
 	}

 	x38_clear_error_info(mci);
 }

 static void x38_process_error_info(struct mem_ctl_info *mci,
 				struct x38_error_info *info)
 {
 	int channel;
 	u64 log;

 	if (!(info->errsts & X38_ERRSTS_BITS))
 		return;

 	if ((info->errsts ^ info->errsts2) & X38_ERRSTS_BITS) {
 		edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci, 0, 0, 0,
 				     -1, -1, -1,
 				     "UE overwrote CE", "", NULL);
 		info->errsts = info->errsts2;
 	}

 	for (channel = 0; channel < x38_channel_num; channel++) {
 		log = info->eccerrlog[channel];
 		if (log & X38_ECCERRLOG_UE) {
 			edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci,
 					     0, 0, 0,
 					     eccerrlog_row(channel, log),
 					     -1, -1,
 					     "x38 UE", "", NULL);
 		} else if (log & X38_ECCERRLOG_CE) {
 			edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci,
 					     0, 0, eccerrlog_syndrome(log),
 					     eccerrlog_row(channel, log),
 					     -1, -1,
 					     "x38 CE", "", NULL);
 		}
 	}
 }

 static void x38_check(struct mem_ctl_info *mci)
 {
 	struct x38_error_info info;

 	debugf1("MC%d: %s()\n", mci->mc_idx, __func__);
 	x38_get_and_clear_error_info(mci, &info);
 	x38_process_error_info(mci, &info);
 }


 void __iomem *x38_map_mchbar(struct pci_dev *pdev)
 {
 	union {
 		u64 mchbar;
 		struct {
 			u32 mchbar_low;
 			u32 mchbar_high;
 		};
 	} u;
 	void __iomem *window;

 	pci_read_config_dword(pdev, X38_MCHBAR_LOW, &u.mchbar_low);
 	pci_write_config_dword(pdev, X38_MCHBAR_LOW, u.mchbar_low | 0x1);
 	pci_read_config_dword(pdev, X38_MCHBAR_HIGH, &u.mchbar_high);
 	u.mchbar &= X38_MCHBAR_MASK;

 	if (u.mchbar != (resource_size_t)u.mchbar) {
 		printk(KERN_ERR
 			"x38: mmio space beyond accessible range (0x%llx)\n",
 			(unsigned long long)u.mchbar);
 		return NULL;
 	}

 	window = ioremap_nocache(u.mchbar, X38_MMR_WINDOW_SIZE);
 	if (!window)
 		printk(KERN_ERR "x38: cannot map mmio space at 0x%llx\n",
 			(unsigned long long)u.mchbar);

 	return window;
 }


 static void x38_get_drbs(void __iomem *window,
 			u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL])
 {
 	int i;

 	for (i = 0; i < X38_RANKS_PER_CHANNEL; i++) {
 		drbs[0][i] = readw(window + X38_C0DRB + 2*i) & X38_DRB_MASK;
 		drbs[1][i] = readw(window + X38_C1DRB + 2*i) & X38_DRB_MASK;
 	}
 }

 static bool x38_is_stacked(struct pci_dev *pdev,
 			u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL])
 {
 	u16 tom;

 	pci_read_config_word(pdev, X38_TOM, &tom);
 	tom &= X38_TOM_MASK;

 	return drbs[X38_CHANNELS - 1][X38_RANKS_PER_CHANNEL - 1] == tom;
 }

 static unsigned long drb_to_nr_pages(
 			u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL],
 			bool stacked, int channel, int rank)
 {
 	int n;

 	n = drbs[channel][rank];
 	if (rank > 0)
 		n -= drbs[channel][rank - 1];
 	if (stacked && (channel == 1) && drbs[channel][rank] ==
 				drbs[channel][X38_RANKS_PER_CHANNEL - 1]) {
 		n -= drbs[0][X38_RANKS_PER_CHANNEL - 1];
 	}

 	n <<= (X38_DRB_SHIFT - PAGE_SHIFT);
 	return n;
 }

 static int x38_probe1(struct pci_dev *pdev, int dev_idx)
 {
 	int rc;
 	int i, j;
 	struct mem_ctl_info *mci = NULL;
 	struct edac_mc_layer layers[2];
 	u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL];
 	bool stacked;
 	void __iomem *window;

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

 	window = x38_map_mchbar(pdev);
 	if (!window)
 		return -ENODEV;

 	x38_get_drbs(window, drbs);

 	how_many_channel(pdev);

 	/* FIXME: unconventional pvt_info usage */
 	layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
 	layers[0].size = X38_RANKS;
 	layers[0].is_virt_csrow = true;
 	layers[1].type = EDAC_MC_LAYER_CHANNEL;
 	layers[1].size = x38_channel_num;
 	layers[1].is_virt_csrow = false;
 	mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers, 0);
 	if (!mci)
 		return -ENOMEM;

 	debugf3("MC: %s(): init mci\n", __func__);

 	mci->dev = &pdev->dev;
 	mci->mtype_cap = MEM_FLAG_DDR2;

 	mci->edac_ctl_cap = EDAC_FLAG_SECDED;
 	mci->edac_cap = EDAC_FLAG_SECDED;

 	mci->mod_name = EDAC_MOD_STR;
 	mci->mod_ver = X38_REVISION;
 	mci->ctl_name = x38_devs[dev_idx].ctl_name;
 	mci->dev_name = pci_name(pdev);
 	mci->edac_check = x38_check;
 	mci->ctl_page_to_phys = NULL;
 	mci->pvt_info = window;

 	stacked = x38_is_stacked(pdev, drbs);

 	/*
 	 * The dram rank boundary (DRB) reg values are boundary addresses
 	 * for each DRAM rank with a granularity of 64MB.  DRB regs are
 	 * cumulative; the last one will contain the total memory
 	 * contained in all ranks.
 	 */
 	for (i = 0; i < mci->nr_csrows; i++) {
 		unsigned long nr_pages;
 		struct csrow_info *csrow = &mci->csrows[i];

 		nr_pages = drb_to_nr_pages(drbs, stacked,
 			i / X38_RANKS_PER_CHANNEL,
 			i % X38_RANKS_PER_CHANNEL);

 		if (nr_pages == 0)
 			continue;

 		for (j = 0; j < x38_channel_num; j++) {
 			struct dimm_info *dimm = csrow->channels[j].dimm;

 			dimm->nr_pages = nr_pages / x38_channel_num;
 			dimm->grain = nr_pages << PAGE_SHIFT;
 			dimm->mtype = MEM_DDR2;
 			dimm->dtype = DEV_UNKNOWN;
 			dimm->edac_mode = EDAC_UNKNOWN;
 		}
 	}

 	x38_clear_error_info(mci);

 	rc = -ENODEV;
 	if (edac_mc_add_mc(mci)) {
 		debugf3("MC: %s(): failed edac_mc_add_mc()\n", __func__);
 		goto fail;
 	}

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

 fail:
 	iounmap(window);
 	if (mci)
 		edac_mc_free(mci);

 	return rc;
 }

 static int __devinit x38_init_one(struct pci_dev *pdev,
 				const struct pci_device_id *ent)
 {
 	int rc;

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

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

 	rc = x38_probe1(pdev, ent->driver_data);
 	if (!mci_pdev)
 		mci_pdev = pci_dev_get(pdev);

 	return rc;
 }

 static void __devexit x38_remove_one(struct pci_dev *pdev)
 {
 	struct mem_ctl_info *mci;

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

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

 	iounmap(mci->pvt_info);

 	edac_mc_free(mci);
 }

 static DEFINE_PCI_DEVICE_TABLE(x38_pci_tbl) = {
 	{
 	 PCI_VEND_DEV(INTEL, X38_HB), PCI_ANY_ID, PCI_ANY_ID, 0, 0,
 	 X38},
 	{
 	 0,
 	 }			/* 0 terminated list. */
 };

 MODULE_DEVICE_TABLE(pci, x38_pci_tbl);

 static struct pci_driver x38_driver = {
 	.name = EDAC_MOD_STR,
 	.probe = x38_init_one,
 	.remove = __devexit_p(x38_remove_one),
 	.id_table = x38_pci_tbl,
 };

 static int __init x38_init(void)
 {
 	int pci_rc;

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

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

 	pci_rc = pci_register_driver(&x38_driver);
 	if (pci_rc < 0)
 		goto fail0;

 	if (!mci_pdev) {
 		x38_registered = 0;
 		mci_pdev = pci_get_device(PCI_VENDOR_ID_INTEL,
 					PCI_DEVICE_ID_INTEL_X38_HB, NULL);
 		if (!mci_pdev) {
 			debugf0("x38 pci_get_device fail\n");
 			pci_rc = -ENODEV;
 			goto fail1;
 		}

 		pci_rc = x38_init_one(mci_pdev, x38_pci_tbl);
 		if (pci_rc < 0) {
 			debugf0("x38 init fail\n");
 			pci_rc = -ENODEV;
 			goto fail1;
 		}
 	}

 	return 0;

 fail1:
 	pci_unregister_driver(&x38_driver);

 fail0:
 	if (mci_pdev)
 		pci_dev_put(mci_pdev);

 	return pci_rc;
 }

 static void __exit x38_exit(void)
 {
 	debugf3("MC: %s()\n", __func__);

 	pci_unregister_driver(&x38_driver);
 	if (!x38_registered) {
 		x38_remove_one(mci_pdev);
 		pci_dev_put(mci_pdev);
 	}
 }

 module_init(x38_init);
 module_exit(x38_exit);

 MODULE_LICENSE("GPL");
 MODULE_AUTHOR("Cluster Computing, Inc. Hitoshi Mitake");
 MODULE_DESCRIPTION("MC support for Intel X38 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 X38 Memory Controller kernel module
	* Copyright (C) 2008 Cluster Computing, Inc.
	*
	* This file may be distributed under the terms of the
	* GNU General Public License.
	*
	* This file is based on i3200_edac.c
	*
	*/

	#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 X38_REVISION "1.1"

	#define EDAC_MOD_STR "x38_edac"

	#define PCI_DEVICE_ID_INTEL_X38_HB 0x29e0

	#define X38_RANKS 8
	#define X38_RANKS_PER_CHANNEL 4
	#define X38_CHANNELS 2

	/* Intel X38 register addresses - device 0 function 0 - DRAM Controller */

	#define X38_MCHBAR_LOW 0x48 /* MCH Memory Mapped Register BAR */
	#define X38_MCHBAR_HIGH 0x4c
	#define X38_MCHBAR_MASK 0xfffffc000ULL /* bits 35:14 */
	#define X38_MMR_WINDOW_SIZE 16384

	#define X38_TOM 0xa0 /* Top of Memory (16b)
	*
	* 15:10 reserved
	* 9:0 total populated physical memory
	*/
	#define X38_TOM_MASK 0x3ff /* bits 9:0 */
	#define X38_TOM_SHIFT 26 /* 64MiB grain */

	#define X38_ERRSTS 0xc8 /* Error Status Register (16b)
	*
	* 15 reserved
	* 14 Isochronous TBWRR Run Behind FIFO Full
	* (ITCV)
	* 13 Isochronous TBWRR Run Behind FIFO Put
	* (ITSTV)
	* 12 reserved
	* 11 MCH Thermal Sensor Event
	* for SMI/SCI/SERR (GTSE)
	* 10 reserved
	* 9 LOCK to non-DRAM Memory Flag (LCKF)
	* 8 reserved
	* 7 DRAM Throttle Flag (DTF)
	* 6:2 reserved
	* 1 Multi-bit DRAM ECC Error Flag (DMERR)
	* 0 Single-bit DRAM ECC Error Flag (DSERR)
	*/
	#define X38_ERRSTS_UE 0x0002
	#define X38_ERRSTS_CE 0x0001
	#define X38_ERRSTS_BITS (X38_ERRSTS_UE \| X38_ERRSTS_CE)


	/* Intel MMIO register space - device 0 function 0 - MMR space */

	#define X38_C0DRB 0x200 /* Channel 0 DRAM Rank Boundary (16b x 4)
	*
	* 15:10 reserved
	* 9:0 Channel 0 DRAM Rank Boundary Address
	*/
	#define X38_C1DRB 0x600 /* Channel 1 DRAM Rank Boundary (16b x 4) */
	#define X38_DRB_MASK 0x3ff /* bits 9:0 */
	#define X38_DRB_SHIFT 26 /* 64MiB grain */

	#define X38_C0ECCERRLOG 0x280 /* Channel 0 ECC Error Log (64b)
	*
	* 63:48 Error Column Address (ERRCOL)
	* 47:32 Error Row Address (ERRROW)
	* 31:29 Error Bank Address (ERRBANK)
	* 28:27 Error Rank Address (ERRRANK)
	* 26:24 reserved
	* 23:16 Error Syndrome (ERRSYND)
	* 15: 2 reserved
	* 1 Multiple Bit Error Status (MERRSTS)
	* 0 Correctable Error Status (CERRSTS)
	*/
	#define X38_C1ECCERRLOG 0x680 /* Channel 1 ECC Error Log (64b) */
	#define X38_ECCERRLOG_CE 0x1
	#define X38_ECCERRLOG_UE 0x2
	#define X38_ECCERRLOG_RANK_BITS 0x18000000
	#define X38_ECCERRLOG_SYNDROME_BITS 0xff0000

	#define X38_CAPID0 0xe0 /* see P.94 of spec for details */

	static int x38_channel_num;

	static int how_many_channel(struct pci_dev *pdev)
	{
	unsigned char capid0_8b; /* 8th byte of CAPID0 */

	pci_read_config_byte(pdev, X38_CAPID0 + 8, &capid0_8b);
	if (capid0_8b & 0x20) { /* check DCD: Dual Channel Disable */
	debugf0("In single channel mode.\n");
	x38_channel_num = 1;
	} else {
	debugf0("In dual channel mode.\n");
	x38_channel_num = 2;
	}

	return x38_channel_num;
	}

	static unsigned long eccerrlog_syndrome(u64 log)
	{
	return (log & X38_ECCERRLOG_SYNDROME_BITS) >> 16;
	}

	static int eccerrlog_row(int channel, u64 log)
	{
	return ((log & X38_ECCERRLOG_RANK_BITS) >> 27) \|
	(channel * X38_RANKS_PER_CHANNEL);
	}

	enum x38_chips {
	X38 = 0,
	};

	struct x38_dev_info {
	const char *ctl_name;
	};

	struct x38_error_info {
	u16 errsts;
	u16 errsts2;
	u64 eccerrlog[X38_CHANNELS];
	};

	static const struct x38_dev_info x38_devs[] = {
	[X38] = {
	.ctl_name = "x38"},
	};

	static struct pci_dev *mci_pdev;
	static int x38_registered = 1;


	static void x38_clear_error_info(struct mem_ctl_info *mci)
	{
	struct pci_dev *pdev;

	pdev = to_pci_dev(mci->dev);

	/*
	* Clear any error bits.
	* (Yes, we really clear bits by writing 1 to them.)
	*/
	pci_write_bits16(pdev, X38_ERRSTS, X38_ERRSTS_BITS,
	X38_ERRSTS_BITS);
	}

	static u64 x38_readq(const void __iomem *addr)
	{
	return readl(addr) \| (((u64)readl(addr + 4)) << 32);
	}

	static void x38_get_and_clear_error_info(struct mem_ctl_info *mci,
	struct x38_error_info *info)
	{
	struct pci_dev *pdev;
	void __iomem *window = mci->pvt_info;

	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, X38_ERRSTS, &info->errsts);
	if (!(info->errsts & X38_ERRSTS_BITS))
	return;

	info->eccerrlog[0] = x38_readq(window + X38_C0ECCERRLOG);
	if (x38_channel_num == 2)
	info->eccerrlog[1] = x38_readq(window + X38_C1ECCERRLOG);

	pci_read_config_word(pdev, X38_ERRSTS, &info->errsts2);

	/*
	* If the error is the same for both reads then the first set
	* of reads is valid. If there is a change then there is a CE
	* with no info and the second set of reads is valid and
	* should be UE info.
	*/
	if ((info->errsts ^ info->errsts2) & X38_ERRSTS_BITS) {
	info->eccerrlog[0] = x38_readq(window + X38_C0ECCERRLOG);
	if (x38_channel_num == 2)
	info->eccerrlog[1] =
	x38_readq(window + X38_C1ECCERRLOG);
	}

	x38_clear_error_info(mci);
	}

	static void x38_process_error_info(struct mem_ctl_info *mci,
	struct x38_error_info *info)
	{
	int channel;
	u64 log;

	if (!(info->errsts & X38_ERRSTS_BITS))
	return;

	if ((info->errsts ^ info->errsts2) & X38_ERRSTS_BITS) {
	edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci, 0, 0, 0,
	-1, -1, -1,
	"UE overwrote CE", "", NULL);
	info->errsts = info->errsts2;
	}

	for (channel = 0; channel < x38_channel_num; channel++) {
	log = info->eccerrlog[channel];
	if (log & X38_ECCERRLOG_UE) {
	edac_mc_handle_error(HW_EVENT_ERR_UNCORRECTED, mci,
	0, 0, 0,
	eccerrlog_row(channel, log),
	-1, -1,
	"x38 UE", "", NULL);
	} else if (log & X38_ECCERRLOG_CE) {
	edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci,
	0, 0, eccerrlog_syndrome(log),
	eccerrlog_row(channel, log),
	-1, -1,
	"x38 CE", "", NULL);
	}
	}
	}

	static void x38_check(struct mem_ctl_info *mci)
	{
	struct x38_error_info info;

	debugf1("MC%d: %s()\n", mci->mc_idx, __func__);
	x38_get_and_clear_error_info(mci, &info);
	x38_process_error_info(mci, &info);
	}


	void __iomem x38_map_mchbar(struct pci_dev pdev)
	{
	union {
	u64 mchbar;
	struct {
	u32 mchbar_low;
	u32 mchbar_high;
	};
	} u;
	void __iomem *window;

	pci_read_config_dword(pdev, X38_MCHBAR_LOW, &u.mchbar_low);
	pci_write_config_dword(pdev, X38_MCHBAR_LOW, u.mchbar_low \| 0x1);
	pci_read_config_dword(pdev, X38_MCHBAR_HIGH, &u.mchbar_high);
	u.mchbar &= X38_MCHBAR_MASK;

	if (u.mchbar != (resource_size_t)u.mchbar) {
	printk(KERN_ERR
	"x38: mmio space beyond accessible range (0x%llx)\n",
	(unsigned long long)u.mchbar);
	return NULL;
	}

	window = ioremap_nocache(u.mchbar, X38_MMR_WINDOW_SIZE);
	if (!window)
	printk(KERN_ERR "x38: cannot map mmio space at 0x%llx\n",
	(unsigned long long)u.mchbar);

	return window;
	}


	static void x38_get_drbs(void __iomem *window,
	u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL])
	{
	int i;

	for (i = 0; i < X38_RANKS_PER_CHANNEL; i++) {
	drbs[0][i] = readw(window + X38_C0DRB + 2*i) & X38_DRB_MASK;
	drbs[1][i] = readw(window + X38_C1DRB + 2*i) & X38_DRB_MASK;
	}
	}

	static bool x38_is_stacked(struct pci_dev *pdev,
	u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL])
	{
	u16 tom;

	pci_read_config_word(pdev, X38_TOM, &tom);
	tom &= X38_TOM_MASK;

	return drbs[X38_CHANNELS - 1][X38_RANKS_PER_CHANNEL - 1] == tom;
	}

	static unsigned long drb_to_nr_pages(
	u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL],
	bool stacked, int channel, int rank)
	{
	int n;

	n = drbs[channel][rank];
	if (rank > 0)
	n -= drbs[channel][rank - 1];
	if (stacked && (channel == 1) && drbs[channel][rank] ==
	drbs[channel][X38_RANKS_PER_CHANNEL - 1]) {
	n -= drbs[0][X38_RANKS_PER_CHANNEL - 1];
	}

	n <<= (X38_DRB_SHIFT - PAGE_SHIFT);
	return n;
	}

	static int x38_probe1(struct pci_dev *pdev, int dev_idx)
	{
	int rc;
	int i, j;
	struct mem_ctl_info *mci = NULL;
	struct edac_mc_layer layers[2];
	u16 drbs[X38_CHANNELS][X38_RANKS_PER_CHANNEL];
	bool stacked;
	void __iomem *window;

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

	window = x38_map_mchbar(pdev);
	if (!window)
	return -ENODEV;

	x38_get_drbs(window, drbs);

	how_many_channel(pdev);

	/* FIXME: unconventional pvt_info usage */
	layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
	layers[0].size = X38_RANKS;
	layers[0].is_virt_csrow = true;
	layers[1].type = EDAC_MC_LAYER_CHANNEL;
	layers[1].size = x38_channel_num;
	layers[1].is_virt_csrow = false;
	mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers, 0);
	if (!mci)
	return -ENOMEM;

	debugf3("MC: %s(): init mci\n", __func__);

	mci->dev = &pdev->dev;
	mci->mtype_cap = MEM_FLAG_DDR2;

	mci->edac_ctl_cap = EDAC_FLAG_SECDED;
	mci->edac_cap = EDAC_FLAG_SECDED;

	mci->mod_name = EDAC_MOD_STR;
	mci->mod_ver = X38_REVISION;
	mci->ctl_name = x38_devs[dev_idx].ctl_name;
	mci->dev_name = pci_name(pdev);
	mci->edac_check = x38_check;
	mci->ctl_page_to_phys = NULL;
	mci->pvt_info = window;

	stacked = x38_is_stacked(pdev, drbs);

	/*
	* The dram rank boundary (DRB) reg values are boundary addresses
	* for each DRAM rank with a granularity of 64MB. DRB regs are
	* cumulative; the last one will contain the total memory
	* contained in all ranks.
	*/
	for (i = 0; i < mci->nr_csrows; i++) {
	unsigned long nr_pages;
	struct csrow_info *csrow = &mci->csrows[i];

	nr_pages = drb_to_nr_pages(drbs, stacked,
	i / X38_RANKS_PER_CHANNEL,
	i % X38_RANKS_PER_CHANNEL);

	if (nr_pages == 0)
	continue;

	for (j = 0; j < x38_channel_num; j++) {
	struct dimm_info *dimm = csrow->channels[j].dimm;

	dimm->nr_pages = nr_pages / x38_channel_num;
	dimm->grain = nr_pages << PAGE_SHIFT;
	dimm->mtype = MEM_DDR2;
	dimm->dtype = DEV_UNKNOWN;
	dimm->edac_mode = EDAC_UNKNOWN;
	}
	}

	x38_clear_error_info(mci);

	rc = -ENODEV;
	if (edac_mc_add_mc(mci)) {
	debugf3("MC: %s(): failed edac_mc_add_mc()\n", __func__);
	goto fail;
	}

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

	fail:
	iounmap(window);
	if (mci)
	edac_mc_free(mci);

	return rc;
	}

	static int __devinit x38_init_one(struct pci_dev *pdev,
	const struct pci_device_id *ent)
	{
	int rc;

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

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

	rc = x38_probe1(pdev, ent->driver_data);
	if (!mci_pdev)
	mci_pdev = pci_dev_get(pdev);

	return rc;
	}

	static void __devexit x38_remove_one(struct pci_dev *pdev)
	{
	struct mem_ctl_info *mci;

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

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

	iounmap(mci->pvt_info);

	edac_mc_free(mci);
	}

	static DEFINE_PCI_DEVICE_TABLE(x38_pci_tbl) = {
	{
	PCI_VEND_DEV(INTEL, X38_HB), PCI_ANY_ID, PCI_ANY_ID, 0, 0,
	X38},
	{
	0,
	} /* 0 terminated list. */
	};

	MODULE_DEVICE_TABLE(pci, x38_pci_tbl);

	static struct pci_driver x38_driver = {
	.name = EDAC_MOD_STR,
	.probe = x38_init_one,
	.remove = __devexit_p(x38_remove_one),
	.id_table = x38_pci_tbl,
	};

	static int __init x38_init(void)
	{
	int pci_rc;

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

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

	pci_rc = pci_register_driver(&x38_driver);
	if (pci_rc < 0)
	goto fail0;

	if (!mci_pdev) {
	x38_registered = 0;
	mci_pdev = pci_get_device(PCI_VENDOR_ID_INTEL,
	PCI_DEVICE_ID_INTEL_X38_HB, NULL);
	if (!mci_pdev) {
	debugf0("x38 pci_get_device fail\n");
	pci_rc = -ENODEV;
	goto fail1;
	}

	pci_rc = x38_init_one(mci_pdev, x38_pci_tbl);
	if (pci_rc < 0) {
	debugf0("x38 init fail\n");
	pci_rc = -ENODEV;
	goto fail1;
	}
	}

	return 0;

	fail1:
	pci_unregister_driver(&x38_driver);

	fail0:
	if (mci_pdev)
	pci_dev_put(mci_pdev);

	return pci_rc;
	}

	static void __exit x38_exit(void)
	{
	debugf3("MC: %s()\n", __func__);

	pci_unregister_driver(&x38_driver);
	if (!x38_registered) {
	x38_remove_one(mci_pdev);
	pci_dev_put(mci_pdev);
	}
	}

	module_init(x38_init);
	module_exit(x38_exit);

	MODULE_LICENSE("GPL");
	MODULE_AUTHOR("Cluster Computing, Inc. Hitoshi Mitake");
	MODULE_DESCRIPTION("MC support for Intel X38 memory hub controllers");

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