/* * (C) 2005, 2006 Linux Networx (http://lnxi.com) * This file may be distributed under the terms of the * GNU General Public License. * * Written Doug Thompson <norsk5@xmission.com> * */ #include <linux/module.h> #include <linux/sysdev.h> #include <linux/ctype.h> #include "edac_core.h" #include "edac_module.h" /* Turn off this whole feature if PCI is not configured */ #ifdef CONFIG_PCI #define EDAC_PCI_SYMLINK "device" /* data variables exported via sysfs */ static int check_pci_errors; /* default NO check PCI parity */ static int edac_pci_panic_on_pe; /* default NO panic on PCI Parity */ static int edac_pci_log_pe = 1; /* log PCI parity errors */ static int edac_pci_log_npe = 1; /* log PCI non-parity error errors */ static int edac_pci_poll_msec = 1000; /* one second workq period */ static atomic_t pci_parity_count = ATOMIC_INIT(0); static atomic_t pci_nonparity_count = ATOMIC_INIT(0); static struct kobject edac_pci_top_main_kobj; static atomic_t edac_pci_sysfs_refcount = ATOMIC_INIT(0); /* getter functions for the data variables */ int edac_pci_get_check_errors(void) { return check_pci_errors; } int edac_pci_get_log_pe(void) { return edac_pci_log_pe; } int edac_pci_get_log_npe(void) { return edac_pci_log_npe; } int edac_pci_get_panic_on_pe(void) { return edac_pci_panic_on_pe; } int edac_pci_get_poll_msec(void) { return edac_pci_poll_msec; } /**************************** EDAC PCI sysfs instance *******************/ static ssize_t instance_pe_count_show(struct edac_pci_ctl_info *pci, char *data) { return sprintf(data, "%u\n", atomic_read(&pci->counters.pe_count)); } static ssize_t instance_npe_count_show(struct edac_pci_ctl_info *pci, char *data) { return sprintf(data, "%u\n", atomic_read(&pci->counters.npe_count)); } #define to_instance(k) container_of(k, struct edac_pci_ctl_info, kobj) #define to_instance_attr(a) container_of(a, struct instance_attribute, attr) /* DEVICE instance kobject release() function */ static void edac_pci_instance_release(struct kobject *kobj) { struct edac_pci_ctl_info *pci; debugf0("%s()\n", __func__); /* Form pointer to containing struct, the pci control struct */ pci = to_instance(kobj); /* decrement reference count on top main kobj */ kobject_put(&edac_pci_top_main_kobj); kfree(pci); /* Free the control struct */ } /* instance specific attribute structure */ struct instance_attribute { struct attribute attr; ssize_t(*show) (struct edac_pci_ctl_info *, char *); ssize_t(*store) (struct edac_pci_ctl_info *, const char *, size_t); }; /* Function to 'show' fields from the edac_pci 'instance' structure */ static ssize_t edac_pci_instance_show(struct kobject *kobj, struct attribute *attr, char *buffer) { struct edac_pci_ctl_info *pci = to_instance(kobj); struct instance_attribute *instance_attr = to_instance_attr(attr); if (instance_attr->show) return instance_attr->show(pci, buffer); return -EIO; } /* Function to 'store' fields into the edac_pci 'instance' structure */ static ssize_t edac_pci_instance_store(struct kobject *kobj, struct attribute *attr, const char *buffer, size_t count) { struct edac_pci_ctl_info *pci = to_instance(kobj); struct instance_attribute *instance_attr = to_instance_attr(attr); if (instance_attr->store) return instance_attr->store(pci, buffer, count); return -EIO; } /* fs_ops table */ static struct sysfs_ops pci_instance_ops = { .show = edac_pci_instance_show, .store = edac_pci_instance_store }; #define INSTANCE_ATTR(_name, _mode, _show, _store) \ static struct instance_attribute attr_instance_##_name = { \ .attr = {.name = __stringify(_name), .mode = _mode }, \ .show = _show, \ .store = _store, \ }; INSTANCE_ATTR(pe_count, S_IRUGO, instance_pe_count_show, NULL); INSTANCE_ATTR(npe_count, S_IRUGO, instance_npe_count_show, NULL); /* pci instance attributes */ static struct instance_attribute *pci_instance_attr[] = { &attr_instance_pe_count, &attr_instance_npe_count, NULL }; /* the ktype for a pci instance */ static struct kobj_type ktype_pci_instance = { .release = edac_pci_instance_release, .sysfs_ops = &pci_instance_ops, .default_attrs = (struct attribute **)pci_instance_attr, }; /* * edac_pci_create_instance_kobj * * construct one EDAC PCI instance's kobject for use */ static int edac_pci_create_instance_kobj(struct edac_pci_ctl_info *pci, int idx) { struct kobject *main_kobj; int err; debugf0("%s()\n", __func__); /* First bump the ref count on the top main kobj, which will * track the number of PCI instances we have, and thus nest * properly on keeping the module loaded */ main_kobj = kobject_get(&edac_pci_top_main_kobj); if (!main_kobj) { err = -ENODEV; goto error_out; } /* And now register this new kobject under the main kobj */ err = kobject_init_and_add(&pci->kobj, &ktype_pci_instance, &edac_pci_top_main_kobj, "pci%d", idx); if (err != 0) { debugf2("%s() failed to register instance pci%d\n", __func__, idx); kobject_put(&edac_pci_top_main_kobj); goto error_out; } kobject_uevent(&pci->kobj, KOBJ_ADD); debugf1("%s() Register instance 'pci%d' kobject\n", __func__, idx); return 0; /* Error unwind statck */ error_out: return err; } /* * edac_pci_unregister_sysfs_instance_kobj * * unregister the kobj for the EDAC PCI instance */ void edac_pci_unregister_sysfs_instance_kobj(struct edac_pci_ctl_info *pci) { debugf0("%s()\n", __func__); /* Unregister the instance kobject and allow its release * function release the main reference count and then * kfree the memory */ kobject_put(&pci->kobj); } /***************************** EDAC PCI sysfs root **********************/ #define to_edacpci(k) container_of(k, struct edac_pci_ctl_info, kobj) #define to_edacpci_attr(a) container_of(a, struct edac_pci_attr, attr) /* simple show/store functions for attributes */ static ssize_t edac_pci_int_show(void *ptr, char *buffer) { int *value = ptr; return sprintf(buffer, "%d\n", *value); } static ssize_t edac_pci_int_store(void *ptr, const char *buffer, size_t count) { int *value = ptr; if (isdigit(*buffer)) *value = simple_strtoul(buffer, NULL, 0); return count; } struct edac_pci_dev_attribute { struct attribute attr; void *value; ssize_t(*show) (void *, char *); ssize_t(*store) (void *, const char *, size_t); }; /* Set of show/store abstract level functions for PCI Parity object */ static ssize_t edac_pci_dev_show(struct kobject *kobj, struct attribute *attr, char *buffer) { struct edac_pci_dev_attribute *edac_pci_dev; edac_pci_dev = (struct edac_pci_dev_attribute *)attr; if (edac_pci_dev->show) return edac_pci_dev->show(edac_pci_dev->value, buffer); return -EIO; } static ssize_t edac_pci_dev_store(struct kobject *kobj, struct attribute *attr, const char *buffer, size_t count) { struct edac_pci_dev_attribute *edac_pci_dev; edac_pci_dev = (struct edac_pci_dev_attribute *)attr; if (edac_pci_dev->show) return edac_pci_dev->store(edac_pci_dev->value, buffer, count); return -EIO; } static struct sysfs_ops edac_pci_sysfs_ops = { .show = edac_pci_dev_show, .store = edac_pci_dev_store }; #define EDAC_PCI_ATTR(_name,_mode,_show,_store) \ static struct edac_pci_dev_attribute edac_pci_attr_##_name = { \ .attr = {.name = __stringify(_name), .mode = _mode }, \ .value = &_name, \ .show = _show, \ .store = _store, \ }; #define EDAC_PCI_STRING_ATTR(_name,_data,_mode,_show,_store) \ static struct edac_pci_dev_attribute edac_pci_attr_##_name = { \ .attr = {.name = __stringify(_name), .mode = _mode }, \ .value = _data, \ .show = _show, \ .store = _store, \ }; /* PCI Parity control files */ EDAC_PCI_ATTR(check_pci_errors, S_IRUGO | S_IWUSR, edac_pci_int_show, edac_pci_int_store); EDAC_PCI_ATTR(edac_pci_log_pe, S_IRUGO | S_IWUSR, edac_pci_int_show, edac_pci_int_store); EDAC_PCI_ATTR(edac_pci_log_npe, S_IRUGO | S_IWUSR, edac_pci_int_show, edac_pci_int_store); EDAC_PCI_ATTR(edac_pci_panic_on_pe, S_IRUGO | S_IWUSR, edac_pci_int_show, edac_pci_int_store); EDAC_PCI_ATTR(pci_parity_count, S_IRUGO, edac_pci_int_show, NULL); EDAC_PCI_ATTR(pci_nonparity_count, S_IRUGO, edac_pci_int_show, NULL); /* Base Attributes of the memory ECC object */ static struct edac_pci_dev_attribute *edac_pci_attr[] = { &edac_pci_attr_check_pci_errors, &edac_pci_attr_edac_pci_log_pe, &edac_pci_attr_edac_pci_log_npe, &edac_pci_attr_edac_pci_panic_on_pe, &edac_pci_attr_pci_parity_count, &edac_pci_attr_pci_nonparity_count, NULL, }; /* * edac_pci_release_main_kobj * * This release function is called when the reference count to the * passed kobj goes to zero. * * This kobj is the 'main' kobject that EDAC PCI instances * link to, and thus provide for proper nesting counts */ static void edac_pci_release_main_kobj(struct kobject *kobj) { debugf0("%s() here to module_put(THIS_MODULE)\n", __func__); /* last reference to top EDAC PCI kobject has been removed, * NOW release our ref count on the core module */ module_put(THIS_MODULE); } /* ktype struct for the EDAC PCI main kobj */ static struct kobj_type ktype_edac_pci_main_kobj = { .release = edac_pci_release_main_kobj, .sysfs_ops = &edac_pci_sysfs_ops, .default_attrs = (struct attribute **)edac_pci_attr, }; /** * edac_pci_main_kobj_setup() * * setup the sysfs for EDAC PCI attributes * assumes edac_class has already been initialized */ int edac_pci_main_kobj_setup(void) { int err; struct sysdev_class *edac_class; debugf0("%s()\n", __func__); /* check and count if we have already created the main kobject */ if (atomic_inc_return(&edac_pci_sysfs_refcount) != 1) return 0; /* First time, so create the main kobject and its * controls and atributes */ edac_class = edac_get_edac_class(); if (edac_class == NULL) { debugf1("%s() no edac_class\n", __func__); err = -ENODEV; goto decrement_count_fail; } /* Bump the reference count on this module to ensure the * modules isn't unloaded until we deconstruct the top * level main kobj for EDAC PCI */ if (!try_module_get(THIS_MODULE)) { debugf1("%s() try_module_get() failed\n", __func__); err = -ENODEV; goto decrement_count_fail; } /* Instanstiate the pci object */ err = kobject_init_and_add(&edac_pci_top_main_kobj, &ktype_edac_pci_main_kobj, &edac_class->kset.kobj, "pci"); if (err) { debugf1("Failed to register '.../edac/pci'\n"); goto kobject_init_and_add_fail; } /* At this point, to 'release' the top level kobject * for EDAC PCI, then edac_pci_main_kobj_teardown() * must be used, for resources to be cleaned up properly */ kobject_uevent(&edac_pci_top_main_kobj, KOBJ_ADD); debugf1("Registered '.../edac/pci' kobject\n"); return 0; /* Error unwind statck */ kobject_init_and_add_fail: module_put(THIS_MODULE); decrement_count_fail: /* if are on this error exit, nothing to tear down */ atomic_dec(&edac_pci_sysfs_refcount); return err; } /* * edac_pci_main_kobj_teardown() * * if no longer linked (needed) remove the top level EDAC PCI * kobject with its controls and attributes */ static void edac_pci_main_kobj_teardown(void) { debugf0("%s()\n", __func__); /* Decrement the count and only if no more controller instances * are connected perform the unregisteration of the top level * main kobj */ if (atomic_dec_return(&edac_pci_sysfs_refcount) == 0) { debugf0("%s() called kobject_put on main kobj\n", __func__); kobject_put(&edac_pci_top_main_kobj); } } /* * * edac_pci_create_sysfs * * Create the controls/attributes for the specified EDAC PCI device */ int edac_pci_create_sysfs(struct edac_pci_ctl_info *pci) { int err; struct kobject *edac_kobj = &pci->kobj; debugf0("%s() idx=%d\n", __func__, pci->pci_idx); /* create the top main EDAC PCI kobject, IF needed */ err = edac_pci_main_kobj_setup(); if (err) return err; /* Create this instance's kobject under the MAIN kobject */ err = edac_pci_create_instance_kobj(pci, pci->pci_idx); if (err) goto unregister_cleanup; err = sysfs_create_link(edac_kobj, &pci->dev->kobj, EDAC_PCI_SYMLINK); if (err) { debugf0("%s() sysfs_create_link() returned err= %d\n", __func__, err); goto symlink_fail; } return 0; /* Error unwind stack */ symlink_fail: edac_pci_unregister_sysfs_instance_kobj(pci); unregister_cleanup: edac_pci_main_kobj_teardown(); return err; } /* * edac_pci_remove_sysfs * * remove the controls and attributes for this EDAC PCI device */ void edac_pci_remove_sysfs(struct edac_pci_ctl_info *pci) { debugf0("%s() index=%d\n", __func__, pci->pci_idx); /* Remove the symlink */ sysfs_remove_link(&pci->kobj, EDAC_PCI_SYMLINK); /* remove this PCI instance's sysfs entries */ edac_pci_unregister_sysfs_instance_kobj(pci); /* Call the main unregister function, which will determine * if this 'pci' is the last instance. * If it is, the main kobject will be unregistered as a result */ debugf0("%s() calling edac_pci_main_kobj_teardown()\n", __func__); edac_pci_main_kobj_teardown(); } /************************ PCI error handling *************************/ static u16 get_pci_parity_status(struct pci_dev *dev, int secondary) { int where; u16 status; where = secondary ? PCI_SEC_STATUS : PCI_STATUS; pci_read_config_word(dev, where, &status); /* If we get back 0xFFFF then we must suspect that the card has been * pulled but the Linux PCI layer has not yet finished cleaning up. * We don't want to report on such devices */ if (status == 0xFFFF) { u32 sanity; pci_read_config_dword(dev, 0, &sanity); if (sanity == 0xFFFFFFFF) return 0; } status &= PCI_STATUS_DETECTED_PARITY | PCI_STATUS_SIG_SYSTEM_ERROR | PCI_STATUS_PARITY; if (status) /* reset only the bits we are interested in */ pci_write_config_word(dev, where, status); return status; } /* Clear any PCI parity errors logged by this device. */ static void edac_pci_dev_parity_clear(struct pci_dev *dev) { u8 header_type; debugf0("%s()\n", __func__); get_pci_parity_status(dev, 0); /* read the device TYPE, looking for bridges */ pci_read_config_byte(dev, PCI_HEADER_TYPE, &header_type); if ((header_type & 0x7F) == PCI_HEADER_TYPE_BRIDGE) get_pci_parity_status(dev, 1); } /* * PCI Parity polling * * Fucntion to retrieve the current parity status * and decode it * */ static void edac_pci_dev_parity_test(struct pci_dev *dev) { unsigned long flags; u16 status; u8 header_type; /* stop any interrupts until we can acquire the status */ local_irq_save(flags); /* read the STATUS register on this device */ status = get_pci_parity_status(dev, 0); /* read the device TYPE, looking for bridges */ pci_read_config_byte(dev, PCI_HEADER_TYPE, &header_type); local_irq_restore(flags); debugf4("PCI STATUS= 0x%04x %s\n", status, dev->dev.bus_id); /* check the status reg for errors */ if (status) { if (status & (PCI_STATUS_SIG_SYSTEM_ERROR)) { edac_printk(KERN_CRIT, EDAC_PCI, "Signaled System Error on %s\n", pci_name(dev)); atomic_inc(&pci_nonparity_count); } if (status & (PCI_STATUS_PARITY)) { edac_printk(KERN_CRIT, EDAC_PCI, "Master Data Parity Error on %s\n", pci_name(dev)); atomic_inc(&pci_parity_count); } if (status & (PCI_STATUS_DETECTED_PARITY)) { edac_printk(KERN_CRIT, EDAC_PCI, "Detected Parity Error on %s\n", pci_name(dev)); atomic_inc(&pci_parity_count); } } debugf4("PCI HEADER TYPE= 0x%02x %s\n", header_type, dev->dev.bus_id); if ((header_type & 0x7F) == PCI_HEADER_TYPE_BRIDGE) { /* On bridges, need to examine secondary status register */ status = get_pci_parity_status(dev, 1); debugf4("PCI SEC_STATUS= 0x%04x %s\n", status, dev->dev.bus_id); /* check the secondary status reg for errors */ if (status) { if (status & (PCI_STATUS_SIG_SYSTEM_ERROR)) { edac_printk(KERN_CRIT, EDAC_PCI, "Bridge " "Signaled System Error on %s\n", pci_name(dev)); atomic_inc(&pci_nonparity_count); } if (status & (PCI_STATUS_PARITY)) { edac_printk(KERN_CRIT, EDAC_PCI, "Bridge " "Master Data Parity Error on " "%s\n", pci_name(dev)); atomic_inc(&pci_parity_count); } if (status & (PCI_STATUS_DETECTED_PARITY)) { edac_printk(KERN_CRIT, EDAC_PCI, "Bridge " "Detected Parity Error on %s\n", pci_name(dev)); atomic_inc(&pci_parity_count); } } } } /* reduce some complexity in definition of the iterator */ typedef void (*pci_parity_check_fn_t) (struct pci_dev *dev); /* * pci_dev parity list iterator * Scan the PCI device list for one pass, looking for SERRORs * Master Parity ERRORS or Parity ERRORs on primary or secondary devices */ static inline void edac_pci_dev_parity_iterator(pci_parity_check_fn_t fn) { struct pci_dev *dev = NULL; /* request for kernel access to the next PCI device, if any, * and while we are looking at it have its reference count * bumped until we are done with it */ while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) { fn(dev); } } /* * edac_pci_do_parity_check * * performs the actual PCI parity check operation */ void edac_pci_do_parity_check(void) { int before_count; debugf3("%s()\n", __func__); /* if policy has PCI check off, leave now */ if (!check_pci_errors) return; before_count = atomic_read(&pci_parity_count); /* scan all PCI devices looking for a Parity Error on devices and * bridges. * The iterator calls pci_get_device() which might sleep, thus * we cannot disable interrupts in this scan. */ edac_pci_dev_parity_iterator(edac_pci_dev_parity_test); /* Only if operator has selected panic on PCI Error */ if (edac_pci_get_panic_on_pe()) { /* If the count is different 'after' from 'before' */ if (before_count != atomic_read(&pci_parity_count)) panic("EDAC: PCI Parity Error"); } } /* * edac_pci_clear_parity_errors * * function to perform an iteration over the PCI devices * and clearn their current status */ void edac_pci_clear_parity_errors(void) { /* Clear any PCI bus parity errors that devices initially have logged * in their registers. */ edac_pci_dev_parity_iterator(edac_pci_dev_parity_clear); } /* * edac_pci_handle_pe * * Called to handle a PARITY ERROR event */ void edac_pci_handle_pe(struct edac_pci_ctl_info *pci, const char *msg) { /* global PE counter incremented by edac_pci_do_parity_check() */ atomic_inc(&pci->counters.pe_count); if (edac_pci_get_log_pe()) edac_pci_printk(pci, KERN_WARNING, "Parity Error ctl: %s %d: %s\n", pci->ctl_name, pci->pci_idx, msg); /* * poke all PCI devices and see which one is the troublemaker * panic() is called if set */ edac_pci_do_parity_check(); } EXPORT_SYMBOL_GPL(edac_pci_handle_pe); /* * edac_pci_handle_npe * * Called to handle a NON-PARITY ERROR event */ void edac_pci_handle_npe(struct edac_pci_ctl_info *pci, const char *msg) { /* global NPE counter incremented by edac_pci_do_parity_check() */ atomic_inc(&pci->counters.npe_count); if (edac_pci_get_log_npe()) edac_pci_printk(pci, KERN_WARNING, "Non-Parity Error ctl: %s %d: %s\n", pci->ctl_name, pci->pci_idx, msg); /* * poke all PCI devices and see which one is the troublemaker * panic() is called if set */ edac_pci_do_parity_check(); } EXPORT_SYMBOL_GPL(edac_pci_handle_npe); /* * Define the PCI parameter to the module */ module_param(check_pci_errors, int, 0644); MODULE_PARM_DESC(check_pci_errors, "Check for PCI bus parity errors: 0=off 1=on"); module_param(edac_pci_panic_on_pe, int, 0644); MODULE_PARM_DESC(edac_pci_panic_on_pe, "Panic on PCI Bus Parity error: 0=off 1=on"); #endif /* CONFIG_PCI */