/*
* (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 */
