drivers/edac/altera_edac.c - kernel/bruno - Git at Google

 /*
  *  Copyright Altera Corporation (C) 2014. All rights reserved.
  *  Copyright 2011-2012 Calxeda, Inc.
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
  * version 2, as published by the Free Software Foundation.
  *
  * This program is distributed in the hope it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  * more details.
  *
  * You should have received a copy of the GNU General Public License along with
  * this program.  If not, see <http://www.gnu.org/licenses/>.
  *
  * Adapted from the highbank_mc_edac driver.
  */

 #include <linux/ctype.h>
 #include <linux/edac.h>
 #include <linux/interrupt.h>
 #include <linux/kernel.h>
 #include <linux/mfd/syscon.h>
 #include <linux/of_platform.h>
 #include <linux/platform_device.h>
 #include <linux/regmap.h>
 #include <linux/types.h>
 #include <linux/uaccess.h>

 #include "edac_core.h"
 #include "edac_module.h"

 #define EDAC_MOD_STR		"altera_edac"
 #define EDAC_VERSION		"1"

 /* SDRAM Controller CtrlCfg Register */
 #define CTLCFG_OFST             0x00

 /* SDRAM Controller CtrlCfg Register Bit Masks */
 #define CTLCFG_ECC_EN           0x400
 #define CTLCFG_ECC_CORR_EN      0x800
 #define CTLCFG_GEN_SB_ERR       0x2000
 #define CTLCFG_GEN_DB_ERR       0x4000

 #define CTLCFG_ECC_AUTO_EN	(CTLCFG_ECC_EN | \
 				 CTLCFG_ECC_CORR_EN)

 /* SDRAM Controller Address Width Register */
 #define DRAMADDRW_OFST          0x2C

 /* SDRAM Controller Address Widths Field Register */
 #define DRAMADDRW_COLBIT_MASK   0x001F
 #define DRAMADDRW_COLBIT_SHIFT  0
 #define DRAMADDRW_ROWBIT_MASK   0x03E0
 #define DRAMADDRW_ROWBIT_SHIFT  5
 #define DRAMADDRW_BANKBIT_MASK	0x1C00
 #define DRAMADDRW_BANKBIT_SHIFT 10
 #define DRAMADDRW_CSBIT_MASK	0xE000
 #define DRAMADDRW_CSBIT_SHIFT   13

 /* SDRAM Controller Interface Data Width Register */
 #define DRAMIFWIDTH_OFST        0x30

 /* SDRAM Controller Interface Data Width Defines */
 #define DRAMIFWIDTH_16B_ECC     24
 #define DRAMIFWIDTH_32B_ECC     40

 /* SDRAM Controller DRAM Status Register */
 #define DRAMSTS_OFST            0x38

 /* SDRAM Controller DRAM Status Register Bit Masks */
 #define DRAMSTS_SBEERR          0x04
 #define DRAMSTS_DBEERR          0x08
 #define DRAMSTS_CORR_DROP       0x10

 /* SDRAM Controller DRAM IRQ Register */
 #define DRAMINTR_OFST           0x3C

 /* SDRAM Controller DRAM IRQ Register Bit Masks */
 #define DRAMINTR_INTREN         0x01
 #define DRAMINTR_SBEMASK        0x02
 #define DRAMINTR_DBEMASK        0x04
 #define DRAMINTR_CORRDROPMASK   0x08
 #define DRAMINTR_INTRCLR        0x10

 /* SDRAM Controller Single Bit Error Count Register */
 #define SBECOUNT_OFST           0x40

 /* SDRAM Controller Single Bit Error Count Register Bit Masks */
 #define SBECOUNT_MASK           0x0F

 /* SDRAM Controller Double Bit Error Count Register */
 #define DBECOUNT_OFST           0x44

 /* SDRAM Controller Double Bit Error Count Register Bit Masks */
 #define DBECOUNT_MASK           0x0F

 /* SDRAM Controller ECC Error Address Register */
 #define ERRADDR_OFST            0x48

 /* SDRAM Controller ECC Error Address Register Bit Masks */
 #define ERRADDR_MASK            0xFFFFFFFF

 /* Altera SDRAM Memory Controller data */
 struct altr_sdram_mc_data {
 	struct regmap *mc_vbase;
 };

 static irqreturn_t altr_sdram_mc_err_handler(int irq, void *dev_id)
 {
 	struct mem_ctl_info *mci = dev_id;
 	struct altr_sdram_mc_data *drvdata = mci->pvt_info;
 	u32 status, err_count, err_addr;

 	/* Error Address is shared by both SBE & DBE */
 	regmap_read(drvdata->mc_vbase, ERRADDR_OFST, &err_addr);

 	regmap_read(drvdata->mc_vbase, DRAMSTS_OFST, &status);

 	if (status & DRAMSTS_DBEERR) {
 		regmap_read(drvdata->mc_vbase, DBECOUNT_OFST, &err_count);
 		panic("\nEDAC: [%d Uncorrectable errors @ 0x%08X]\n",
 		      err_count, err_addr);
 	}
 	if (status & DRAMSTS_SBEERR) {
 		regmap_read(drvdata->mc_vbase, SBECOUNT_OFST, &err_count);
 		edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci, err_count,
 				     err_addr >> PAGE_SHIFT,
 				     err_addr & ~PAGE_MASK, 0,
 				     0, 0, -1, mci->ctl_name, "");
 	}

 	regmap_write(drvdata->mc_vbase,	DRAMINTR_OFST,
 		     (DRAMINTR_INTRCLR | DRAMINTR_INTREN));

 	return IRQ_HANDLED;
 }

 #ifdef CONFIG_EDAC_DEBUG
 static ssize_t altr_sdr_mc_err_inject_write(struct file *file,
 					    const char __user *data,
 					    size_t count, loff_t *ppos)
 {
 	struct mem_ctl_info *mci = file->private_data;
 	struct altr_sdram_mc_data *drvdata = mci->pvt_info;
 	u32 *ptemp;
 	dma_addr_t dma_handle;
 	u32 reg, read_reg;

 	ptemp = dma_alloc_coherent(mci->pdev, 16, &dma_handle, GFP_KERNEL);
 	if (!ptemp) {
 		dma_free_coherent(mci->pdev, 16, ptemp, dma_handle);
 		edac_printk(KERN_ERR, EDAC_MC,
 			    "Inject: Buffer Allocation error\n");
 		return -ENOMEM;
 	}

 	regmap_read(drvdata->mc_vbase, CTLCFG_OFST, &read_reg);
 	read_reg &= ~(CTLCFG_GEN_SB_ERR | CTLCFG_GEN_DB_ERR);

 	/* Error are injected by writing a word while the SBE or DBE
 	 * bit in the CTLCFG register is set. Reading the word will
 	 * trigger the SBE or DBE error and the corresponding IRQ.
 	 */
 	if (count == 3) {
 		edac_printk(KERN_ALERT, EDAC_MC,
 			    "Inject Double bit error\n");
 		regmap_write(drvdata->mc_vbase, CTLCFG_OFST,
 			     (read_reg | CTLCFG_GEN_DB_ERR));
 	} else {
 		edac_printk(KERN_ALERT, EDAC_MC,
 			    "Inject Single bit error\n");
 		regmap_write(drvdata->mc_vbase,	CTLCFG_OFST,
 			     (read_reg | CTLCFG_GEN_SB_ERR));
 	}

 	ptemp[0] = 0x5A5A5A5A;
 	ptemp[1] = 0xA5A5A5A5;

 	/* Clear the error injection bits */
 	regmap_write(drvdata->mc_vbase,	CTLCFG_OFST, read_reg);
 	/* Ensure it has been written out */
 	wmb();

 	/*
 	 * To trigger the error, we need to read the data back
 	 * (the data was written with errors above).
 	 * The ACCESS_ONCE macros and printk are used to prevent the
 	 * the compiler optimizing these reads out.
 	 */
 	reg = ACCESS_ONCE(ptemp[0]);
 	read_reg = ACCESS_ONCE(ptemp[1]);
 	/* Force Read */
 	rmb();

 	edac_printk(KERN_ALERT, EDAC_MC, "Read Data [0x%X, 0x%X]\n",
 		    reg, read_reg);

 	dma_free_coherent(mci->pdev, 16, ptemp, dma_handle);

 	return count;
 }

 static const struct file_operations altr_sdr_mc_debug_inject_fops = {
 	.open = simple_open,
 	.write = altr_sdr_mc_err_inject_write,
 	.llseek = generic_file_llseek,
 };

 static void altr_sdr_mc_create_debugfs_nodes(struct mem_ctl_info *mci)
 {
 	if (mci->debugfs)
 		debugfs_create_file("inject_ctrl", S_IWUSR, mci->debugfs, mci,
 				    &altr_sdr_mc_debug_inject_fops);
 }
 #else
 static void altr_sdr_mc_create_debugfs_nodes(struct mem_ctl_info *mci)
 {}
 #endif

 /* Get total memory size in bytes */
 static u32 altr_sdram_get_total_mem_size(struct regmap *mc_vbase)
 {
 	u32 size, read_reg, row, bank, col, cs, width;

 	if (regmap_read(mc_vbase, DRAMADDRW_OFST, &read_reg) < 0)
 		return 0;

 	if (regmap_read(mc_vbase, DRAMIFWIDTH_OFST, &width) < 0)
 		return 0;

 	col = (read_reg & DRAMADDRW_COLBIT_MASK) >>
 		DRAMADDRW_COLBIT_SHIFT;
 	row = (read_reg & DRAMADDRW_ROWBIT_MASK) >>
 		DRAMADDRW_ROWBIT_SHIFT;
 	bank = (read_reg & DRAMADDRW_BANKBIT_MASK) >>
 		DRAMADDRW_BANKBIT_SHIFT;
 	cs = (read_reg & DRAMADDRW_CSBIT_MASK) >>
 		DRAMADDRW_CSBIT_SHIFT;

 	/* Correct for ECC as its not addressible */
 	if (width == DRAMIFWIDTH_32B_ECC)
 		width = 32;
 	if (width == DRAMIFWIDTH_16B_ECC)
 		width = 16;

 	/* calculate the SDRAM size base on this info */
 	size = 1 << (row + bank + col);
 	size = size * cs * (width / 8);
 	return size;
 }

 static int altr_sdram_probe(struct platform_device *pdev)
 {
 	struct edac_mc_layer layers[2];
 	struct mem_ctl_info *mci;
 	struct altr_sdram_mc_data *drvdata;
 	struct regmap *mc_vbase;
 	struct dimm_info *dimm;
 	u32 read_reg, mem_size;
 	int irq;
 	int res = 0;

 	/* Validate the SDRAM controller has ECC enabled */
 	/* Grab the register range from the sdr controller in device tree */
 	mc_vbase = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
 						   "altr,sdr-syscon");
 	if (IS_ERR(mc_vbase)) {
 		edac_printk(KERN_ERR, EDAC_MC,
 			    "regmap for altr,sdr-syscon lookup failed.\n");
 		return -ENODEV;
 	}

 	if (regmap_read(mc_vbase, CTLCFG_OFST, &read_reg) ||
 	    ((read_reg & CTLCFG_ECC_AUTO_EN) !=	CTLCFG_ECC_AUTO_EN)) {
 		edac_printk(KERN_ERR, EDAC_MC,
 			    "No ECC/ECC disabled [0x%08X]\n", read_reg);
 		return -ENODEV;
 	}

 	/* Grab memory size from device tree. */
 	mem_size = altr_sdram_get_total_mem_size(mc_vbase);
 	if (!mem_size) {
 		edac_printk(KERN_ERR, EDAC_MC,
 			    "Unable to calculate memory size\n");
 		return -ENODEV;
 	}

 	/* Ensure the SDRAM Interrupt is disabled and cleared */
 	if (regmap_write(mc_vbase, DRAMINTR_OFST, DRAMINTR_INTRCLR)) {
 		edac_printk(KERN_ERR, EDAC_MC,
 			    "Error clearing SDRAM ECC IRQ\n");
 		return -ENODEV;
 	}

 	irq = platform_get_irq(pdev, 0);
 	if (irq < 0) {
 		edac_printk(KERN_ERR, EDAC_MC,
 			    "No irq %d in DT\n", irq);
 		return -ENODEV;
 	}

 	layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
 	layers[0].size = 1;
 	layers[0].is_virt_csrow = true;
 	layers[1].type = EDAC_MC_LAYER_CHANNEL;
 	layers[1].size = 1;
 	layers[1].is_virt_csrow = false;
 	mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers,
 			    sizeof(struct altr_sdram_mc_data));
 	if (!mci)
 		return -ENOMEM;

 	mci->pdev = &pdev->dev;
 	drvdata = mci->pvt_info;
 	drvdata->mc_vbase = mc_vbase;
 	platform_set_drvdata(pdev, mci);

 	if (!devres_open_group(&pdev->dev, NULL, GFP_KERNEL)) {
 		res = -ENOMEM;
 		goto free;
 	}

 	mci->mtype_cap = MEM_FLAG_DDR3;
 	mci->edac_ctl_cap = EDAC_FLAG_NONE | EDAC_FLAG_SECDED;
 	mci->edac_cap = EDAC_FLAG_SECDED;
 	mci->mod_name = EDAC_MOD_STR;
 	mci->mod_ver = EDAC_VERSION;
 	mci->ctl_name = dev_name(&pdev->dev);
 	mci->scrub_mode = SCRUB_SW_SRC;
 	mci->dev_name = dev_name(&pdev->dev);

 	dimm = *mci->dimms;
 	dimm->nr_pages = ((mem_size - 1) >> PAGE_SHIFT) + 1;
 	dimm->grain = 8;
 	dimm->dtype = DEV_X8;
 	dimm->mtype = MEM_DDR3;
 	dimm->edac_mode = EDAC_SECDED;

 	res = edac_mc_add_mc(mci);
 	if (res < 0)
 		goto err;

 	res = devm_request_irq(&pdev->dev, irq, altr_sdram_mc_err_handler,
 			       0, dev_name(&pdev->dev), mci);
 	if (res < 0) {
 		edac_mc_printk(mci, KERN_ERR,
 			       "Unable to request irq %d\n", irq);
 		res = -ENODEV;
 		goto err2;
 	}

 	if (regmap_write(drvdata->mc_vbase, DRAMINTR_OFST,
 			 (DRAMINTR_INTRCLR | DRAMINTR_INTREN))) {
 		edac_mc_printk(mci, KERN_ERR,
 			       "Error enabling SDRAM ECC IRQ\n");
 		res = -ENODEV;
 		goto err2;
 	}

 	altr_sdr_mc_create_debugfs_nodes(mci);

 	devres_close_group(&pdev->dev, NULL);

 	return 0;

 err2:
 	edac_mc_del_mc(&pdev->dev);
 err:
 	devres_release_group(&pdev->dev, NULL);
 free:
 	edac_mc_free(mci);
 	edac_printk(KERN_ERR, EDAC_MC,
 		    "EDAC Probe Failed; Error %d\n", res);

 	return res;
 }

 static int altr_sdram_remove(struct platform_device *pdev)
 {
 	struct mem_ctl_info *mci = platform_get_drvdata(pdev);

 	edac_mc_del_mc(&pdev->dev);
 	edac_mc_free(mci);
 	platform_set_drvdata(pdev, NULL);

 	return 0;
 }

 static const struct of_device_id altr_sdram_ctrl_of_match[] = {
 	{ .compatible = "altr,sdram-edac", },
 	{},
 };
 MODULE_DEVICE_TABLE(of, altr_sdram_ctrl_of_match);

 static struct platform_driver altr_sdram_edac_driver = {
 	.probe = altr_sdram_probe,
 	.remove = altr_sdram_remove,
 	.driver = {
 		.name = "altr_sdram_edac",
 		.of_match_table = altr_sdram_ctrl_of_match,
 	},
 };

 module_platform_driver(altr_sdram_edac_driver);

 MODULE_LICENSE("GPL v2");
 MODULE_AUTHOR("Thor Thayer");
 MODULE_DESCRIPTION("EDAC Driver for Altera SDRAM Controller");
	/*
	* Copyright Altera Corporation (C) 2014. All rights reserved.
	* Copyright 2011-2012 Calxeda, Inc.
	*
	* This program is free software; you can redistribute it and/or modify it
	* under the terms and conditions of the GNU General Public License,
	* version 2, as published by the Free Software Foundation.
	*
	* This program is distributed in the hope it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	* more details.
	*
	* You should have received a copy of the GNU General Public License along with
	* this program. If not, see <http://www.gnu.org/licenses/>.
	*
	* Adapted from the highbank_mc_edac driver.
	*/

	#include <linux/ctype.h>
	#include <linux/edac.h>
	#include <linux/interrupt.h>
	#include <linux/kernel.h>
	#include <linux/mfd/syscon.h>
	#include <linux/of_platform.h>
	#include <linux/platform_device.h>
	#include <linux/regmap.h>
	#include <linux/types.h>
	#include <linux/uaccess.h>

	#include "edac_core.h"
	#include "edac_module.h"

	#define EDAC_MOD_STR "altera_edac"
	#define EDAC_VERSION "1"

	/* SDRAM Controller CtrlCfg Register */
	#define CTLCFG_OFST 0x00

	/* SDRAM Controller CtrlCfg Register Bit Masks */
	#define CTLCFG_ECC_EN 0x400
	#define CTLCFG_ECC_CORR_EN 0x800
	#define CTLCFG_GEN_SB_ERR 0x2000
	#define CTLCFG_GEN_DB_ERR 0x4000

	#define CTLCFG_ECC_AUTO_EN (CTLCFG_ECC_EN \| \
	CTLCFG_ECC_CORR_EN)

	/* SDRAM Controller Address Width Register */
	#define DRAMADDRW_OFST 0x2C

	/* SDRAM Controller Address Widths Field Register */
	#define DRAMADDRW_COLBIT_MASK 0x001F
	#define DRAMADDRW_COLBIT_SHIFT 0
	#define DRAMADDRW_ROWBIT_MASK 0x03E0
	#define DRAMADDRW_ROWBIT_SHIFT 5
	#define DRAMADDRW_BANKBIT_MASK 0x1C00
	#define DRAMADDRW_BANKBIT_SHIFT 10
	#define DRAMADDRW_CSBIT_MASK 0xE000
	#define DRAMADDRW_CSBIT_SHIFT 13

	/* SDRAM Controller Interface Data Width Register */
	#define DRAMIFWIDTH_OFST 0x30

	/* SDRAM Controller Interface Data Width Defines */
	#define DRAMIFWIDTH_16B_ECC 24
	#define DRAMIFWIDTH_32B_ECC 40

	/* SDRAM Controller DRAM Status Register */
	#define DRAMSTS_OFST 0x38

	/* SDRAM Controller DRAM Status Register Bit Masks */
	#define DRAMSTS_SBEERR 0x04
	#define DRAMSTS_DBEERR 0x08
	#define DRAMSTS_CORR_DROP 0x10

	/* SDRAM Controller DRAM IRQ Register */
	#define DRAMINTR_OFST 0x3C

	/* SDRAM Controller DRAM IRQ Register Bit Masks */
	#define DRAMINTR_INTREN 0x01
	#define DRAMINTR_SBEMASK 0x02
	#define DRAMINTR_DBEMASK 0x04
	#define DRAMINTR_CORRDROPMASK 0x08
	#define DRAMINTR_INTRCLR 0x10

	/* SDRAM Controller Single Bit Error Count Register */
	#define SBECOUNT_OFST 0x40

	/* SDRAM Controller Single Bit Error Count Register Bit Masks */
	#define SBECOUNT_MASK 0x0F

	/* SDRAM Controller Double Bit Error Count Register */
	#define DBECOUNT_OFST 0x44

	/* SDRAM Controller Double Bit Error Count Register Bit Masks */
	#define DBECOUNT_MASK 0x0F

	/* SDRAM Controller ECC Error Address Register */
	#define ERRADDR_OFST 0x48

	/* SDRAM Controller ECC Error Address Register Bit Masks */
	#define ERRADDR_MASK 0xFFFFFFFF

	/* Altera SDRAM Memory Controller data */
	struct altr_sdram_mc_data {
	struct regmap *mc_vbase;
	};

	static irqreturn_t altr_sdram_mc_err_handler(int irq, void *dev_id)
	{
	struct mem_ctl_info *mci = dev_id;
	struct altr_sdram_mc_data *drvdata = mci->pvt_info;
	u32 status, err_count, err_addr;

	/* Error Address is shared by both SBE & DBE */
	regmap_read(drvdata->mc_vbase, ERRADDR_OFST, &err_addr);

	regmap_read(drvdata->mc_vbase, DRAMSTS_OFST, &status);

	if (status & DRAMSTS_DBEERR) {
	regmap_read(drvdata->mc_vbase, DBECOUNT_OFST, &err_count);
	panic("\nEDAC: [%d Uncorrectable errors @ 0x%08X]\n",
	err_count, err_addr);
	}
	if (status & DRAMSTS_SBEERR) {
	regmap_read(drvdata->mc_vbase, SBECOUNT_OFST, &err_count);
	edac_mc_handle_error(HW_EVENT_ERR_CORRECTED, mci, err_count,
	err_addr >> PAGE_SHIFT,
	err_addr & ~PAGE_MASK, 0,
	0, 0, -1, mci->ctl_name, "");
	}

	regmap_write(drvdata->mc_vbase, DRAMINTR_OFST,
	(DRAMINTR_INTRCLR \| DRAMINTR_INTREN));

	return IRQ_HANDLED;
	}

	#ifdef CONFIG_EDAC_DEBUG
	static ssize_t altr_sdr_mc_err_inject_write(struct file *file,
	const char __user *data,
	size_t count, loff_t *ppos)
	{
	struct mem_ctl_info *mci = file->private_data;
	struct altr_sdram_mc_data *drvdata = mci->pvt_info;
	u32 *ptemp;
	dma_addr_t dma_handle;
	u32 reg, read_reg;

	ptemp = dma_alloc_coherent(mci->pdev, 16, &dma_handle, GFP_KERNEL);
	if (!ptemp) {
	dma_free_coherent(mci->pdev, 16, ptemp, dma_handle);
	edac_printk(KERN_ERR, EDAC_MC,
	"Inject: Buffer Allocation error\n");
	return -ENOMEM;
	}

	regmap_read(drvdata->mc_vbase, CTLCFG_OFST, &read_reg);
	read_reg &= ~(CTLCFG_GEN_SB_ERR \| CTLCFG_GEN_DB_ERR);

	/* Error are injected by writing a word while the SBE or DBE
	* bit in the CTLCFG register is set. Reading the word will
	* trigger the SBE or DBE error and the corresponding IRQ.
	*/
	if (count == 3) {
	edac_printk(KERN_ALERT, EDAC_MC,
	"Inject Double bit error\n");
	regmap_write(drvdata->mc_vbase, CTLCFG_OFST,
	(read_reg \| CTLCFG_GEN_DB_ERR));
	} else {
	edac_printk(KERN_ALERT, EDAC_MC,
	"Inject Single bit error\n");
	regmap_write(drvdata->mc_vbase, CTLCFG_OFST,
	(read_reg \| CTLCFG_GEN_SB_ERR));
	}

	ptemp[0] = 0x5A5A5A5A;
	ptemp[1] = 0xA5A5A5A5;

	/* Clear the error injection bits */
	regmap_write(drvdata->mc_vbase, CTLCFG_OFST, read_reg);
	/* Ensure it has been written out */
	wmb();

	/*
	* To trigger the error, we need to read the data back
	* (the data was written with errors above).
	* The ACCESS_ONCE macros and printk are used to prevent the
	* the compiler optimizing these reads out.
	*/
	reg = ACCESS_ONCE(ptemp[0]);
	read_reg = ACCESS_ONCE(ptemp[1]);
	/* Force Read */
	rmb();

	edac_printk(KERN_ALERT, EDAC_MC, "Read Data [0x%X, 0x%X]\n",
	reg, read_reg);

	dma_free_coherent(mci->pdev, 16, ptemp, dma_handle);

	return count;
	}

	static const struct file_operations altr_sdr_mc_debug_inject_fops = {
	.open = simple_open,
	.write = altr_sdr_mc_err_inject_write,
	.llseek = generic_file_llseek,
	};

	static void altr_sdr_mc_create_debugfs_nodes(struct mem_ctl_info *mci)
	{
	if (mci->debugfs)
	debugfs_create_file("inject_ctrl", S_IWUSR, mci->debugfs, mci,
	&altr_sdr_mc_debug_inject_fops);
	}
	#else
	static void altr_sdr_mc_create_debugfs_nodes(struct mem_ctl_info *mci)
	{}
	#endif

	/* Get total memory size in bytes */
	static u32 altr_sdram_get_total_mem_size(struct regmap *mc_vbase)
	{
	u32 size, read_reg, row, bank, col, cs, width;

	if (regmap_read(mc_vbase, DRAMADDRW_OFST, &read_reg) < 0)
	return 0;

	if (regmap_read(mc_vbase, DRAMIFWIDTH_OFST, &width) < 0)
	return 0;

	col = (read_reg & DRAMADDRW_COLBIT_MASK) >>
	DRAMADDRW_COLBIT_SHIFT;
	row = (read_reg & DRAMADDRW_ROWBIT_MASK) >>
	DRAMADDRW_ROWBIT_SHIFT;
	bank = (read_reg & DRAMADDRW_BANKBIT_MASK) >>
	DRAMADDRW_BANKBIT_SHIFT;
	cs = (read_reg & DRAMADDRW_CSBIT_MASK) >>
	DRAMADDRW_CSBIT_SHIFT;

	/* Correct for ECC as its not addressible */
	if (width == DRAMIFWIDTH_32B_ECC)
	width = 32;
	if (width == DRAMIFWIDTH_16B_ECC)
	width = 16;

	/* calculate the SDRAM size base on this info */
	size = 1 << (row + bank + col);
	size = size * cs * (width / 8);
	return size;
	}

	static int altr_sdram_probe(struct platform_device *pdev)
	{
	struct edac_mc_layer layers[2];
	struct mem_ctl_info *mci;
	struct altr_sdram_mc_data *drvdata;
	struct regmap *mc_vbase;
	struct dimm_info *dimm;
	u32 read_reg, mem_size;
	int irq;
	int res = 0;

	/* Validate the SDRAM controller has ECC enabled */
	/* Grab the register range from the sdr controller in device tree */
	mc_vbase = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
	"altr,sdr-syscon");
	if (IS_ERR(mc_vbase)) {
	edac_printk(KERN_ERR, EDAC_MC,
	"regmap for altr,sdr-syscon lookup failed.\n");
	return -ENODEV;
	}

	if (regmap_read(mc_vbase, CTLCFG_OFST, &read_reg) \|\|
	((read_reg & CTLCFG_ECC_AUTO_EN) != CTLCFG_ECC_AUTO_EN)) {
	edac_printk(KERN_ERR, EDAC_MC,
	"No ECC/ECC disabled [0x%08X]\n", read_reg);
	return -ENODEV;
	}

	/* Grab memory size from device tree. */
	mem_size = altr_sdram_get_total_mem_size(mc_vbase);
	if (!mem_size) {
	edac_printk(KERN_ERR, EDAC_MC,
	"Unable to calculate memory size\n");
	return -ENODEV;
	}

	/* Ensure the SDRAM Interrupt is disabled and cleared */
	if (regmap_write(mc_vbase, DRAMINTR_OFST, DRAMINTR_INTRCLR)) {
	edac_printk(KERN_ERR, EDAC_MC,
	"Error clearing SDRAM ECC IRQ\n");
	return -ENODEV;
	}

	irq = platform_get_irq(pdev, 0);
	if (irq < 0) {
	edac_printk(KERN_ERR, EDAC_MC,
	"No irq %d in DT\n", irq);
	return -ENODEV;
	}

	layers[0].type = EDAC_MC_LAYER_CHIP_SELECT;
	layers[0].size = 1;
	layers[0].is_virt_csrow = true;
	layers[1].type = EDAC_MC_LAYER_CHANNEL;
	layers[1].size = 1;
	layers[1].is_virt_csrow = false;
	mci = edac_mc_alloc(0, ARRAY_SIZE(layers), layers,
	sizeof(struct altr_sdram_mc_data));
	if (!mci)
	return -ENOMEM;

	mci->pdev = &pdev->dev;
	drvdata = mci->pvt_info;
	drvdata->mc_vbase = mc_vbase;
	platform_set_drvdata(pdev, mci);

	if (!devres_open_group(&pdev->dev, NULL, GFP_KERNEL)) {
	res = -ENOMEM;
	goto free;
	}

	mci->mtype_cap = MEM_FLAG_DDR3;
	mci->edac_ctl_cap = EDAC_FLAG_NONE \| EDAC_FLAG_SECDED;
	mci->edac_cap = EDAC_FLAG_SECDED;
	mci->mod_name = EDAC_MOD_STR;
	mci->mod_ver = EDAC_VERSION;
	mci->ctl_name = dev_name(&pdev->dev);
	mci->scrub_mode = SCRUB_SW_SRC;
	mci->dev_name = dev_name(&pdev->dev);

	dimm = *mci->dimms;
	dimm->nr_pages = ((mem_size - 1) >> PAGE_SHIFT) + 1;
	dimm->grain = 8;
	dimm->dtype = DEV_X8;
	dimm->mtype = MEM_DDR3;
	dimm->edac_mode = EDAC_SECDED;

	res = edac_mc_add_mc(mci);
	if (res < 0)
	goto err;

	res = devm_request_irq(&pdev->dev, irq, altr_sdram_mc_err_handler,
	0, dev_name(&pdev->dev), mci);
	if (res < 0) {
	edac_mc_printk(mci, KERN_ERR,
	"Unable to request irq %d\n", irq);
	res = -ENODEV;
	goto err2;
	}

	if (regmap_write(drvdata->mc_vbase, DRAMINTR_OFST,
	(DRAMINTR_INTRCLR \| DRAMINTR_INTREN))) {
	edac_mc_printk(mci, KERN_ERR,
	"Error enabling SDRAM ECC IRQ\n");
	res = -ENODEV;
	goto err2;
	}

	altr_sdr_mc_create_debugfs_nodes(mci);

	devres_close_group(&pdev->dev, NULL);

	return 0;

	err2:
	edac_mc_del_mc(&pdev->dev);
	err:
	devres_release_group(&pdev->dev, NULL);
	free:
	edac_mc_free(mci);
	edac_printk(KERN_ERR, EDAC_MC,
	"EDAC Probe Failed; Error %d\n", res);

	return res;
	}

	static int altr_sdram_remove(struct platform_device *pdev)
	{
	struct mem_ctl_info *mci = platform_get_drvdata(pdev);

	edac_mc_del_mc(&pdev->dev);
	edac_mc_free(mci);
	platform_set_drvdata(pdev, NULL);

	return 0;
	}

	static const struct of_device_id altr_sdram_ctrl_of_match[] = {
	{ .compatible = "altr,sdram-edac", },
	{},
	};
	MODULE_DEVICE_TABLE(of, altr_sdram_ctrl_of_match);

	static struct platform_driver altr_sdram_edac_driver = {
	.probe = altr_sdram_probe,
	.remove = altr_sdram_remove,
	.driver = {
	.name = "altr_sdram_edac",
	.of_match_table = altr_sdram_ctrl_of_match,
	},
	};

	module_platform_driver(altr_sdram_edac_driver);

	MODULE_LICENSE("GPL v2");
	MODULE_AUTHOR("Thor Thayer");
	MODULE_DESCRIPTION("EDAC Driver for Altera SDRAM Controller");