/* Intel 7 core Memory Controller kernel module (Nehalem) * * This file may be distributed under the terms of the * GNU General Public License version 2 only. * * Copyright (c) 2009 by: * Mauro Carvalho Chehab * * Red Hat Inc. http://www.redhat.com * * Forked and adapted from the i5400_edac driver * * Based on the following public Intel datasheets: * Intel Core i7 Processor Extreme Edition and Intel Core i7 Processor * Datasheet, Volume 2: * http://download.intel.com/design/processor/datashts/320835.pdf * Intel Xeon Processor 5500 Series Datasheet Volume 2 * http://www.intel.com/Assets/PDF/datasheet/321322.pdf * also available at: * http://www.arrownac.com/manufacturers/intel/s/nehalem/5500-datasheet-v2.pdf */ #include #include #include #include #include #include #include #include "edac_core.h" /* * Alter this version for the module when modifications are made */ #define I7CORE_REVISION " Ver: 1.0.0 " __DATE__ #define EDAC_MOD_STR "i7core_edac" /* HACK: temporary, just to enable all logs, for now */ #undef debugf0 #define debugf0(fmt, arg...) edac_printk(KERN_INFO, "i7core", fmt, ##arg) /* * Debug macros */ #define i7core_printk(level, fmt, arg...) \ edac_printk(level, "i7core", fmt, ##arg) #define i7core_mc_printk(mci, level, fmt, arg...) \ edac_mc_chipset_printk(mci, level, "i7core", fmt, ##arg) /* * i7core Memory Controller Registers */ /* OFFSETS for Device 3 Function 0 */ #define MC_CONTROL 0x48 #define MC_STATUS 0x4c #define MC_MAX_DOD 0x64 /* OFFSETS for Devices 4,5 and 6 Function 0 */ #define MC_CHANNEL_ADDR_MATCH 0xf0 #define MC_CHANNEL_ERROR_MASK 0xf8 #define MC_CHANNEL_ERROR_INJECT 0xfc #define INJECT_ADDR_PARITY 0x10 #define INJECT_ECC 0x08 #define MASK_CACHELINE 0x06 #define MASK_FULL_CACHELINE 0x06 #define MASK_MSB32_CACHELINE 0x04 #define MASK_LSB32_CACHELINE 0x02 #define NO_MASK_CACHELINE 0x00 #define REPEAT_EN 0x01 /* * i7core structs */ #define NUM_CHANS 3 #define NUM_FUNCS 1 struct i7core_info { u32 mc_control; u32 mc_status; u32 max_dod; }; struct i7core_inject { int enable; u32 section; u32 type; u32 eccmask; /* Error address mask */ int channel, dimm, rank, bank, page, col; }; struct i7core_pvt { struct pci_dev *pci_mcr; /* Dev 3:0 */ struct pci_dev *pci_ch[NUM_CHANS][NUM_FUNCS]; struct i7core_info info; struct i7core_inject inject; }; /* Device name and register DID (Device ID) */ struct i7core_dev_info { const char *ctl_name; /* name for this device */ u16 fsb_mapping_errors; /* DID for the branchmap,control */ }; static int chan_pci_ids[NUM_CHANS] = { PCI_DEVICE_ID_INTEL_I7_MC_CH0_CTRL, /* Dev 4 */ PCI_DEVICE_ID_INTEL_I7_MC_CH1_CTRL, /* Dev 5 */ PCI_DEVICE_ID_INTEL_I7_MC_CH2_CTRL, /* Dev 6 */ }; /* Table of devices attributes supported by this driver */ static const struct i7core_dev_info i7core_devs[] = { { .ctl_name = "i7 Core", .fsb_mapping_errors = PCI_DEVICE_ID_INTEL_I7_MCR, }, }; static struct edac_pci_ctl_info *i7core_pci; /**************************************************************************** Anciliary status routines ****************************************************************************/ /* MC_CONTROL bits */ #define CH2_ACTIVE(pvt) ((pvt)->info.mc_control & 1 << 10) #define CH1_ACTIVE(pvt) ((pvt)->info.mc_control & 1 << 9) #define CH0_ACTIVE(pvt) ((pvt)->info.mc_control & 1 << 8) #define ECCx8(pvt) ((pvt)->info.mc_control & 1 << 1) /* MC_STATUS bits */ #define ECC_ENABLED(pvt) ((pvt)->info.mc_status & 1 << 3) #define CH2_DISABLED(pvt) ((pvt)->info.mc_status & 1 << 2) #define CH1_DISABLED(pvt) ((pvt)->info.mc_status & 1 << 1) #define CH0_DISABLED(pvt) ((pvt)->info.mc_status & 1 << 0) /* MC_MAX_DOD read functions */ static inline int maxnumdimms(struct i7core_pvt *pvt) { return (pvt->info.max_dod & 0x3) + 1; } static inline int maxnumrank(struct i7core_pvt *pvt) { static int ranks[4] = { 1, 2, 4, -EINVAL }; return ranks[(pvt->info.max_dod >> 2) & 0x3]; } static inline int maxnumbank(struct i7core_pvt *pvt) { static int banks[4] = { 4, 8, 16, -EINVAL }; return banks[(pvt->info.max_dod >> 4) & 0x3]; } static inline int maxnumrow(struct i7core_pvt *pvt) { static int rows[8] = { 1 << 12, 1 << 13, 1 << 14, 1 << 15, 1 << 16, -EINVAL, -EINVAL, -EINVAL, }; return rows[((pvt->info.max_dod >> 6) & 0x7)]; } static inline int maxnumcol(struct i7core_pvt *pvt) { static int cols[8] = { 1 << 10, 1 << 11, 1 << 12, -EINVAL, }; return cols[((pvt->info.max_dod >> 9) & 0x3) << 12]; } /**************************************************************************** Memory check routines ****************************************************************************/ static int get_dimm_config(struct mem_ctl_info *mci) { struct i7core_pvt *pvt = mci->pvt_info; pci_read_config_dword(pvt->pci_mcr, MC_CONTROL, &pvt->info.mc_control); pci_read_config_dword(pvt->pci_mcr, MC_STATUS, &pvt->info.mc_status); pci_read_config_dword(pvt->pci_mcr, MC_MAX_DOD, &pvt->info.max_dod); debugf0("Channels active [%c][%c][%c] - enabled [%c][%c][%c]\n", CH0_ACTIVE(pvt)?'0':'-', CH1_ACTIVE(pvt)?'1':'-', CH2_ACTIVE(pvt)?'2':'-', CH0_DISABLED(pvt)?'-':'0', CH1_DISABLED(pvt)?'-':'1', CH2_DISABLED(pvt)?'-':'2'); if (ECC_ENABLED(pvt)) debugf0("ECC enabled with x%d SDCC\n", ECCx8(pvt)?8:4); else debugf0("ECC disabled\n"); /* FIXME: need to handle the error codes */ debugf0("DOD Maximum limits: DIMMS: %d, %d-ranked, %d-banked\n", maxnumdimms(pvt), maxnumrank(pvt), maxnumbank(pvt)); debugf0("DOD Maximum rows x colums = 0x%x x 0x%x\n", maxnumrow(pvt), maxnumcol(pvt)); return 0; } /**************************************************************************** Error insertion routines ****************************************************************************/ /* The i7core has independent error injection features per channel. However, to have a simpler code, we don't allow enabling error injection on more than one channel. Also, since a change at an inject parameter will be applied only at enable, we're disabling error injection on all write calls to the sysfs nodes that controls the error code injection. */ static void disable_inject(struct mem_ctl_info *mci) { struct i7core_pvt *pvt = mci->pvt_info; pvt->inject.enable = 0; pci_write_config_dword(pvt->pci_ch[pvt->inject.channel][0], MC_CHANNEL_ERROR_MASK, 0); } /* * i7core inject inject.section * * accept and store error injection inject.section value * bit 0 - refers to the lower 32-byte half cacheline * bit 1 - refers to the upper 32-byte half cacheline */ static ssize_t i7core_inject_section_store(struct mem_ctl_info *mci, const char *data, size_t count) { struct i7core_pvt *pvt = mci->pvt_info; unsigned long value; int rc; if (pvt->inject.enable) disable_inject(mci); rc = strict_strtoul(data, 10, &value); if ((rc < 0) || (value > 3)) return 0; pvt->inject.section = (u32) value; return count; } static ssize_t i7core_inject_section_show(struct mem_ctl_info *mci, char *data) { struct i7core_pvt *pvt = mci->pvt_info; return sprintf(data, "0x%08x\n", pvt->inject.section); } /* * i7core inject.type * * accept and store error injection inject.section value * bit 0 - repeat enable - Enable error repetition * bit 1 - inject ECC error * bit 2 - inject parity error */ static ssize_t i7core_inject_type_store(struct mem_ctl_info *mci, const char *data, size_t count) { struct i7core_pvt *pvt = mci->pvt_info; unsigned long value; int rc; if (pvt->inject.enable) disable_inject(mci); rc = strict_strtoul(data, 10, &value); if ((rc < 0) || (value > 7)) return 0; pvt->inject.type = (u32) value; return count; } static ssize_t i7core_inject_type_show(struct mem_ctl_info *mci, char *data) { struct i7core_pvt *pvt = mci->pvt_info; return sprintf(data, "0x%08x\n", pvt->inject.type); } /* * i7core_inject_inject.eccmask_store * * The type of error (UE/CE) will depend on the inject.eccmask value: * Any bits set to a 1 will flip the corresponding ECC bit * Correctable errors can be injected by flipping 1 bit or the bits within * a symbol pair (2 consecutive aligned 8-bit pairs - i.e. 7:0 and 15:8 or * 23:16 and 31:24). Flipping bits in two symbol pairs will cause an * uncorrectable error to be injected. */ static ssize_t i7core_inject_eccmask_store(struct mem_ctl_info *mci, const char *data, size_t count) { struct i7core_pvt *pvt = mci->pvt_info; unsigned long value; int rc; if (pvt->inject.enable) disable_inject(mci); rc = strict_strtoul(data, 10, &value); if (rc < 0) return 0; pvt->inject.eccmask = (u32) value; return count; } static ssize_t i7core_inject_eccmask_show(struct mem_ctl_info *mci, char *data) { struct i7core_pvt *pvt = mci->pvt_info; return sprintf(data, "0x%08x\n", pvt->inject.eccmask); } /* * i7core_addrmatch * * The type of error (UE/CE) will depend on the inject.eccmask value: * Any bits set to a 1 will flip the corresponding ECC bit * Correctable errors can be injected by flipping 1 bit or the bits within * a symbol pair (2 consecutive aligned 8-bit pairs - i.e. 7:0 and 15:8 or * 23:16 and 31:24). Flipping bits in two symbol pairs will cause an * uncorrectable error to be injected. */ static ssize_t i7core_inject_addrmatch_store(struct mem_ctl_info *mci, const char *data, size_t count) { struct i7core_pvt *pvt = mci->pvt_info; char *cmd, *val; long value; int rc; if (pvt->inject.enable) disable_inject(mci); do { cmd = strsep((char **) &data, ":"); if (!cmd) break; val = strsep((char **) &data, " \n\t"); if (!val) return cmd - data; if (!strcasecmp(val,"any")) value = -1; else { rc = strict_strtol(val, 10, &value); if ((rc < 0) || (value < 0)) return cmd - data; } if (!strcasecmp(cmd,"channel")) { if (value < 3) pvt->inject.channel = value; else return cmd - data; } else if (!strcasecmp(cmd,"dimm")) { if (value < 4) pvt->inject.dimm = value; else return cmd - data; } else if (!strcasecmp(cmd,"rank")) { if (value < 4) pvt->inject.rank = value; else return cmd - data; } else if (!strcasecmp(cmd,"bank")) { if (value < 4) pvt->inject.bank = value; else return cmd - data; } else if (!strcasecmp(cmd,"page")) { if (value <= 0xffff) pvt->inject.page = value; else return cmd - data; } else if (!strcasecmp(cmd,"col") || !strcasecmp(cmd,"column")) { if (value <= 0x3fff) pvt->inject.col = value; else return cmd - data; } } while (1); return count; } static ssize_t i7core_inject_addrmatch_show(struct mem_ctl_info *mci, char *data) { struct i7core_pvt *pvt = mci->pvt_info; char channel[4], dimm[4], bank[4], rank[4], page[7], col[7]; if (pvt->inject.channel < 0) sprintf(channel, "any"); else sprintf(channel, "%d", pvt->inject.channel); if (pvt->inject.dimm < 0) sprintf(dimm, "any"); else sprintf(dimm, "%d", pvt->inject.dimm); if (pvt->inject.bank < 0) sprintf(bank, "any"); else sprintf(bank, "%d", pvt->inject.bank); if (pvt->inject.rank < 0) sprintf(rank, "any"); else sprintf(rank, "%d", pvt->inject.rank); if (pvt->inject.page < 0) sprintf(page, "any"); else sprintf(page, "0x%04x", pvt->inject.page); if (pvt->inject.col < 0) sprintf(col, "any"); else sprintf(col, "0x%04x", pvt->inject.col); return sprintf(data, "channel: %s\ndimm: %s\nbank: %s\n" "rank: %s\npage: %s\ncolumn: %s\n", channel, dimm, bank, rank, page, col); } /* * This routine prepares the Memory Controller for error injection. * The error will be injected when some process tries to write to the * memory that matches the given criteria. * The criteria can be set in terms of a mask where dimm, rank, bank, page * and col can be specified. * A -1 value for any of the mask items will make the MCU to ignore * that matching criteria for error injection. * * It should be noticed that the error will only happen after a write operation * on a memory that matches the condition. if REPEAT_EN is not enabled at * inject mask, then it will produce just one error. Otherwise, it will repeat * until the injectmask would be cleaned. * * FIXME: This routine assumes that MAXNUMDIMMS value of MC_MAX_DOD * is reliable enough to check if the MC is using the * three channels. However, this is not clear at the datasheet. */ static ssize_t i7core_inject_enable_store(struct mem_ctl_info *mci, const char *data, size_t count) { struct i7core_pvt *pvt = mci->pvt_info; u32 injectmask; u64 mask = 0; int rc; long enable; rc = strict_strtoul(data, 10, &enable); if ((rc < 0)) return 0; if (enable) { pvt->inject.enable = 1; } else { disable_inject(mci); return count; } /* Sets pvt->inject.dimm mask */ if (pvt->inject.dimm < 0) mask |= 1l << 41; else { if (maxnumdimms(pvt) > 2) mask |= (pvt->inject.dimm & 0x3l) << 35; else mask |= (pvt->inject.dimm & 0x1l) << 36; } /* Sets pvt->inject.rank mask */ if (pvt->inject.rank < 0) mask |= 1l << 40; else { if (maxnumdimms(pvt) > 2) mask |= (pvt->inject.rank & 0x1l) << 34; else mask |= (pvt->inject.rank & 0x3l) << 34; } /* Sets pvt->inject.bank mask */ if (pvt->inject.bank < 0) mask |= 1l << 39; else mask |= (pvt->inject.bank & 0x15l) << 30; /* Sets pvt->inject.page mask */ if (pvt->inject.page < 0) mask |= 1l << 38; else mask |= (pvt->inject.page & 0xffffl) << 14; /* Sets pvt->inject.column mask */ if (pvt->inject.col < 0) mask |= 1l << 37; else mask |= (pvt->inject.col & 0x3fffl); pci_write_config_qword(pvt->pci_ch[pvt->inject.channel][0], MC_CHANNEL_ADDR_MATCH, mask); pci_write_config_dword(pvt->pci_ch[pvt->inject.channel][0], MC_CHANNEL_ERROR_MASK, pvt->inject.eccmask); /* * bit 0: REPEAT_EN * bits 1-2: MASK_HALF_CACHELINE * bit 3: INJECT_ECC * bit 4: INJECT_ADDR_PARITY */ injectmask = (pvt->inject.type & 1) && (pvt->inject.section & 0x3) << 1 && (pvt->inject.type & 0x6) << (3 - 1); pci_write_config_dword(pvt->pci_ch[pvt->inject.channel][0], MC_CHANNEL_ERROR_MASK, injectmask); debugf0("Error inject addr match 0x%016llx, ecc 0x%08x, inject 0x%08x\n", mask, pvt->inject.eccmask, injectmask); return count; } static ssize_t i7core_inject_enable_show(struct mem_ctl_info *mci, char *data) { struct i7core_pvt *pvt = mci->pvt_info; return sprintf(data, "%d\n", pvt->inject.enable); } /* * Sysfs struct */ static struct mcidev_sysfs_attribute i7core_inj_attrs[] = { { .attr = { .name = "inject_section", .mode = (S_IRUGO | S_IWUSR) }, .show = i7core_inject_section_show, .store = i7core_inject_section_store, }, { .attr = { .name = "inject_type", .mode = (S_IRUGO | S_IWUSR) }, .show = i7core_inject_type_show, .store = i7core_inject_type_store, }, { .attr = { .name = "inject_eccmask", .mode = (S_IRUGO | S_IWUSR) }, .show = i7core_inject_eccmask_show, .store = i7core_inject_eccmask_store, }, { .attr = { .name = "inject_addrmatch", .mode = (S_IRUGO | S_IWUSR) }, .show = i7core_inject_addrmatch_show, .store = i7core_inject_addrmatch_store, }, { .attr = { .name = "inject_enable", .mode = (S_IRUGO | S_IWUSR) }, .show = i7core_inject_enable_show, .store = i7core_inject_enable_store, }, }; /**************************************************************************** Device initialization routines: put/get, init/exit ****************************************************************************/ /* * i7core_put_devices 'put' all the devices that we have * reserved via 'get' */ static void i7core_put_devices(struct mem_ctl_info *mci) { struct i7core_pvt *pvt = mci->pvt_info; int i, n; pci_dev_put(pvt->pci_mcr); /* Release all PCI device functions at MTR channel controllers */ for (i = 0; i < NUM_CHANS; i++) for (n = 0; n < NUM_FUNCS; n++) pci_dev_put(pvt->pci_ch[i][n]); } /* * i7core_get_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 i7core_get_devices(struct mem_ctl_info *mci, int dev_idx) { struct i7core_pvt *pvt; struct pci_dev *pdev; int i, n, func; pvt = mci->pvt_info; memset(pvt, 0, sizeof(*pvt)); pdev = pci_get_device(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_I7_MCR, NULL); if (!pdev) { i7core_printk(KERN_ERR, "Couldn't get PCI ID %04x:%04x function 0\n", PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_I7_MCR); return -ENODEV; } pvt->pci_mcr=pdev; /* Get dimm basic config */ get_dimm_config(mci); /* Retrieve all needed functions at MTR channel controllers */ for (i = 0; i < NUM_CHANS; i++) { pdev = NULL; for (n = 0; n < NUM_FUNCS; n++) { pdev = pci_get_device(PCI_VENDOR_ID_INTEL, chan_pci_ids[i], pdev); if (!pdev) { /* End of list, leave */ i7core_printk(KERN_ERR, "Device not found: PCI ID %04x:%04x " "found only %d functions " "(broken BIOS?)\n", PCI_VENDOR_ID_INTEL, chan_pci_ids[i], n); i7core_put_devices(mci); return -ENODEV; } func = PCI_FUNC(pdev->devfn); pvt->pci_ch[i][func] = pdev; } } i7core_printk(KERN_INFO, "Driver loaded.\n"); return 0; } /* * i7core_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 i7core_probe(struct pci_dev *pdev, const struct pci_device_id *id) { struct mem_ctl_info *mci; struct i7core_pvt *pvt; int rc; int num_channels; int num_csrows; int num_dimms_per_channel; int dev_idx = id->driver_data; if (dev_idx >= ARRAY_SIZE(i7core_devs)) return -EINVAL; /* wake up device */ rc = pci_enable_device(pdev); if (rc == -EIO) return rc; debugf0("MC: " __FILE__ ": %s(), pdev bus %u dev=0x%x fn=0x%x\n", __func__, pdev->bus->number, PCI_SLOT(pdev->devfn), PCI_FUNC(pdev->devfn)); /* We only are looking for func 0 of the set */ if (PCI_FUNC(pdev->devfn) != 0) return -ENODEV; num_channels = NUM_CHANS; /* FIXME: FAKE data, since we currently don't now how to get this */ num_dimms_per_channel = 4; num_csrows = num_dimms_per_channel; /* allocate a new MC control structure */ mci = edac_mc_alloc(sizeof(*pvt), num_csrows, num_channels, 0); if (mci == NULL) return -ENOMEM; debugf0("MC: " __FILE__ ": %s(): mci = %p\n", __func__, mci); mci->dev = &pdev->dev; /* record ptr to the generic device */ dev_set_drvdata(mci->dev, mci); pvt = mci->pvt_info; // pvt->system_address = pdev; /* Record this device in our private */ // pvt->maxch = num_channels; // pvt->maxdimmperch = num_dimms_per_channel; /* 'get' the pci devices we want to reserve for our use */ if (i7core_get_devices(mci, dev_idx)) goto fail0; mci->mc_idx = 0; mci->mtype_cap = MEM_FLAG_FB_DDR2; /* FIXME: it uses DDR3 */ mci->edac_ctl_cap = EDAC_FLAG_NONE; mci->edac_cap = EDAC_FLAG_NONE; mci->mod_name = "i7core_edac.c"; mci->mod_ver = I7CORE_REVISION; mci->ctl_name = i7core_devs[dev_idx].ctl_name; mci->dev_name = pci_name(pdev); mci->ctl_page_to_phys = NULL; mci->mc_driver_sysfs_attributes = i7core_inj_attrs; /* add this new MC control structure to EDAC's list of MCs */ if (edac_mc_add_mc(mci)) { debugf0("MC: " __FILE__ ": %s(): failed edac_mc_add_mc()\n", __func__); /* FIXME: perhaps some code should go here that disables error * reporting if we just enabled it */ goto fail1; } /* allocating generic PCI control info */ i7core_pci = edac_pci_create_generic_ctl(&pdev->dev, EDAC_MOD_STR); if (!i7core_pci) { printk(KERN_WARNING "%s(): Unable to create PCI control\n", __func__); printk(KERN_WARNING "%s(): PCI error report via EDAC not setup\n", __func__); } /* Default error mask is any memory */ pvt->inject.channel = -1; pvt->inject.dimm = -1; pvt->inject.rank = -1; pvt->inject.bank = -1; pvt->inject.page = -1; pvt->inject.col = -1; return 0; fail1: i7core_put_devices(mci); fail0: edac_mc_free(mci); return -ENODEV; } /* * i7core_remove destructor for one instance of device * */ static void __devexit i7core_remove(struct pci_dev *pdev) { struct mem_ctl_info *mci; debugf0(__FILE__ ": %s()\n", __func__); if (i7core_pci) edac_pci_release_generic_ctl(i7core_pci); mci = edac_mc_del_mc(&pdev->dev); if (!mci) return; /* retrieve references to resources, and free those resources */ i7core_put_devices(mci); edac_mc_free(mci); } /* * pci_device_id table for which devices we are looking for * * The "E500P" device is the first device supported. */ static const struct pci_device_id i7core_pci_tbl[] __devinitdata = { {PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_I7_MCR)}, {0,} /* 0 terminated list. */ }; MODULE_DEVICE_TABLE(pci, i7core_pci_tbl); /* * i7core_driver pci_driver structure for this module * */ static struct pci_driver i7core_driver = { .name = "i7core_edac", .probe = i7core_probe, .remove = __devexit_p(i7core_remove), .id_table = i7core_pci_tbl, }; /* * i7core_init Module entry function * Try to initialize this module for its devices */ static int __init i7core_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(&i7core_driver); return (pci_rc < 0) ? pci_rc : 0; } /* * i7core_exit() Module exit function * Unregister the driver */ static void __exit i7core_exit(void) { debugf2("MC: " __FILE__ ": %s()\n", __func__); pci_unregister_driver(&i7core_driver); } module_init(i7core_init); module_exit(i7core_exit); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Mauro Carvalho Chehab "); MODULE_AUTHOR("Red Hat Inc. (http://www.redhat.com)"); MODULE_DESCRIPTION("MC Driver for Intel i7 Core memory controllers - " I7CORE_REVISION); module_param(edac_op_state, int, 0444); MODULE_PARM_DESC(edac_op_state, "EDAC Error Reporting state: 0=Poll,1=NMI");