Initial commit

drivers/edac/edac_pci.c

@@ -0,0 +1,500 @@
+/*
+ * EDAC PCI component
+ *
+ * Author: Dave Jiang <djiang@mvista.com>
+ *
+ * 2007 (c) MontaVista Software, Inc. This file is licensed under
+ * the terms of the GNU General Public License version 2. This program
+ * is licensed "as is" without any warranty of any kind, whether express
+ * or implied.
+ *
+ */
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/smp.h>
+#include <linux/init.h>
+#include <linux/sysctl.h>
+#include <linux/highmem.h>
+#include <linux/timer.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/list.h>
+#include <linux/ctype.h>
+#include <linux/workqueue.h>
+#include <asm/uaccess.h>
+#include <asm/page.h>
+
+#include "edac_core.h"
+#include "edac_module.h"
+
+static DEFINE_MUTEX(edac_pci_ctls_mutex);
+static LIST_HEAD(edac_pci_list);
+static atomic_t pci_indexes = ATOMIC_INIT(0);
+
+/*
+ * edac_pci_alloc_ctl_info
+ *
+ *	The alloc() function for the 'edac_pci' control info
+ *	structure. The chip driver will allocate one of these for each
+ *	edac_pci it is going to control/register with the EDAC CORE.
+ */
+struct edac_pci_ctl_info *edac_pci_alloc_ctl_info(unsigned int sz_pvt,
+						const char *edac_pci_name)
+{
+	struct edac_pci_ctl_info *pci;
+	void *p = NULL, *pvt;
+	unsigned int size;
+
+	edac_dbg(1, "\n");
+
+	pci = edac_align_ptr(&p, sizeof(*pci), 1);
+	pvt = edac_align_ptr(&p, 1, sz_pvt);
+	size = ((unsigned long)pvt) + sz_pvt;
+
+	/* Alloc the needed control struct memory */
+	pci = kzalloc(size, GFP_KERNEL);
+	if (pci  == NULL)
+		return NULL;
+
+	/* Now much private space */
+	pvt = sz_pvt ? ((char *)pci) + ((unsigned long)pvt) : NULL;
+
+	pci->pvt_info = pvt;
+	pci->op_state = OP_ALLOC;
+
+	snprintf(pci->name, strlen(edac_pci_name) + 1, "%s", edac_pci_name);
+
+	return pci;
+}
+EXPORT_SYMBOL_GPL(edac_pci_alloc_ctl_info);
+
+/*
+ * edac_pci_free_ctl_info()
+ *
+ *	Last action on the pci control structure.
+ *
+ *	call the remove sysfs information, which will unregister
+ *	this control struct's kobj. When that kobj's ref count
+ *	goes to zero, its release function will be call and then
+ *	kfree() the memory.
+ */
+void edac_pci_free_ctl_info(struct edac_pci_ctl_info *pci)
+{
+	edac_dbg(1, "\n");
+
+	edac_pci_remove_sysfs(pci);
+}
+EXPORT_SYMBOL_GPL(edac_pci_free_ctl_info);
+
+/*
+ * find_edac_pci_by_dev()
+ * 	scans the edac_pci list for a specific 'struct device *'
+ *
+ *	return NULL if not found, or return control struct pointer
+ */
+static struct edac_pci_ctl_info *find_edac_pci_by_dev(struct device *dev)
+{
+	struct edac_pci_ctl_info *pci;
+	struct list_head *item;
+
+	edac_dbg(1, "\n");
+
+	list_for_each(item, &edac_pci_list) {
+		pci = list_entry(item, struct edac_pci_ctl_info, link);
+
+		if (pci->dev == dev)
+			return pci;
+	}
+
+	return NULL;
+}
+
+/*
+ * add_edac_pci_to_global_list
+ * 	Before calling this function, caller must assign a unique value to
+ * 	edac_dev->pci_idx.
+ * 	Return:
+ * 		0 on success
+ * 		1 on failure
+ */
+static int add_edac_pci_to_global_list(struct edac_pci_ctl_info *pci)
+{
+	struct list_head *item, *insert_before;
+	struct edac_pci_ctl_info *rover;
+
+	edac_dbg(1, "\n");
+
+	insert_before = &edac_pci_list;
+
+	/* Determine if already on the list */
+	rover = find_edac_pci_by_dev(pci->dev);
+	if (unlikely(rover != NULL))
+		goto fail0;
+
+	/* Insert in ascending order by 'pci_idx', so find position */
+	list_for_each(item, &edac_pci_list) {
+		rover = list_entry(item, struct edac_pci_ctl_info, link);
+
+		if (rover->pci_idx >= pci->pci_idx) {
+			if (unlikely(rover->pci_idx == pci->pci_idx))
+				goto fail1;
+
+			insert_before = item;
+			break;
+		}
+	}
+
+	list_add_tail_rcu(&pci->link, insert_before);
+	return 0;
+
+fail0:
+	edac_printk(KERN_WARNING, EDAC_PCI,
+		"%s (%s) %s %s already assigned %d\n",
+		dev_name(rover->dev), edac_dev_name(rover),
+		rover->mod_name, rover->ctl_name, rover->pci_idx);
+	return 1;
+
+fail1:
+	edac_printk(KERN_WARNING, EDAC_PCI,
+		"but in low-level driver: attempt to assign\n"
+		"\tduplicate pci_idx %d in %s()\n", rover->pci_idx,
+		__func__);
+	return 1;
+}
+
+/*
+ * del_edac_pci_from_global_list
+ *
+ *	remove the PCI control struct from the global list
+ */
+static void del_edac_pci_from_global_list(struct edac_pci_ctl_info *pci)
+{
+	list_del_rcu(&pci->link);
+
+	/* these are for safe removal of devices from global list while
+	 * NMI handlers may be traversing list
+	 */
+	synchronize_rcu();
+	INIT_LIST_HEAD(&pci->link);
+}
+
+#if 0
+/* Older code, but might use in the future */
+
+/*
+ * edac_pci_find()
+ * 	Search for an edac_pci_ctl_info structure whose index is 'idx'
+ *
+ * If found, return a pointer to the structure
+ * Else return NULL.
+ *
+ * Caller must hold pci_ctls_mutex.
+ */
+struct edac_pci_ctl_info *edac_pci_find(int idx)
+{
+	struct list_head *item;
+	struct edac_pci_ctl_info *pci;
+
+	/* Iterage over list, looking for exact match of ID */
+	list_for_each(item, &edac_pci_list) {
+		pci = list_entry(item, struct edac_pci_ctl_info, link);
+
+		if (pci->pci_idx >= idx) {
+			if (pci->pci_idx == idx)
+				return pci;
+
+			/* not on list, so terminate early */
+			break;
+		}
+	}
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(edac_pci_find);
+#endif
+
+/*
+ * edac_pci_workq_function()
+ *
+ * 	periodic function that performs the operation
+ *	scheduled by a workq request, for a given PCI control struct
+ */
+static void edac_pci_workq_function(struct work_struct *work_req)
+{
+	struct delayed_work *d_work = to_delayed_work(work_req);
+	struct edac_pci_ctl_info *pci = to_edac_pci_ctl_work(d_work);
+	int msec;
+	unsigned long delay;
+
+	edac_dbg(3, "checking\n");
+
+	mutex_lock(&edac_pci_ctls_mutex);
+
+	if (pci->op_state == OP_RUNNING_POLL) {
+		/* we might be in POLL mode, but there may NOT be a poll func
+		 */
+		if ((pci->edac_check != NULL) && edac_pci_get_check_errors())
+			pci->edac_check(pci);
+
+		/* if we are on a one second period, then use round */
+		msec = edac_pci_get_poll_msec();
+		if (msec == 1000)
+			delay = round_jiffies_relative(msecs_to_jiffies(msec));
+		else
+			delay = msecs_to_jiffies(msec);
+
+		/* Reschedule only if we are in POLL mode */
+		queue_delayed_work(edac_workqueue, &pci->work, delay);
+	}
+
+	mutex_unlock(&edac_pci_ctls_mutex);
+}
+
+/*
+ * edac_pci_workq_setup()
+ * 	initialize a workq item for this edac_pci instance
+ * 	passing in the new delay period in msec
+ *
+ *	locking model:
+ *		called when 'edac_pci_ctls_mutex' is locked
+ */
+static void edac_pci_workq_setup(struct edac_pci_ctl_info *pci,
+				 unsigned int msec)
+{
+	edac_dbg(0, "\n");
+
+	INIT_DELAYED_WORK(&pci->work, edac_pci_workq_function);
+	queue_delayed_work(edac_workqueue, &pci->work,
+			msecs_to_jiffies(edac_pci_get_poll_msec()));
+}
+
+/*
+ * edac_pci_workq_teardown()
+ * 	stop the workq processing on this edac_pci instance
+ */
+static void edac_pci_workq_teardown(struct edac_pci_ctl_info *pci)
+{
+	int status;
+
+	edac_dbg(0, "\n");
+
+	status = cancel_delayed_work(&pci->work);
+	if (status == 0)
+		flush_workqueue(edac_workqueue);
+}
+
+/*
+ * edac_pci_reset_delay_period
+ *
+ *	called with a new period value for the workq period
+ *	a) stop current workq timer
+ *	b) restart workq timer with new value
+ */
+void edac_pci_reset_delay_period(struct edac_pci_ctl_info *pci,
+				 unsigned long value)
+{
+	edac_dbg(0, "\n");
+
+	edac_pci_workq_teardown(pci);
+
+	/* need to lock for the setup */
+	mutex_lock(&edac_pci_ctls_mutex);
+
+	edac_pci_workq_setup(pci, value);
+
+	mutex_unlock(&edac_pci_ctls_mutex);
+}
+EXPORT_SYMBOL_GPL(edac_pci_reset_delay_period);
+
+/*
+ * edac_pci_alloc_index: Allocate a unique PCI index number
+ *
+ * Return:
+ *      allocated index number
+ *
+ */
+int edac_pci_alloc_index(void)
+{
+	return atomic_inc_return(&pci_indexes) - 1;
+}
+EXPORT_SYMBOL_GPL(edac_pci_alloc_index);
+
+/*
+ * edac_pci_add_device: Insert the 'edac_dev' structure into the
+ * edac_pci global list and create sysfs entries associated with
+ * edac_pci structure.
+ * @pci: pointer to the edac_device structure to be added to the list
+ * @edac_idx: A unique numeric identifier to be assigned to the
+ * 'edac_pci' structure.
+ *
+ * Return:
+ *      0       Success
+ *      !0      Failure
+ */
+int edac_pci_add_device(struct edac_pci_ctl_info *pci, int edac_idx)
+{
+	edac_dbg(0, "\n");
+
+	pci->pci_idx = edac_idx;
+	pci->start_time = jiffies;
+
+	mutex_lock(&edac_pci_ctls_mutex);
+
+	if (add_edac_pci_to_global_list(pci))
+		goto fail0;
+
+	if (edac_pci_create_sysfs(pci)) {
+		edac_pci_printk(pci, KERN_WARNING,
+				"failed to create sysfs pci\n");
+		goto fail1;
+	}
+
+	if (pci->edac_check != NULL) {
+		pci->op_state = OP_RUNNING_POLL;
+
+		edac_pci_workq_setup(pci, 1000);
+	} else {
+		pci->op_state = OP_RUNNING_INTERRUPT;
+	}
+
+	edac_pci_printk(pci, KERN_INFO,
+			"Giving out device to module '%s' controller '%s':"
+			" DEV '%s' (%s)\n",
+			pci->mod_name,
+			pci->ctl_name,
+			edac_dev_name(pci), edac_op_state_to_string(pci->op_state));
+
+	mutex_unlock(&edac_pci_ctls_mutex);
+	return 0;
+
+	/* error unwind stack */
+fail1:
+	del_edac_pci_from_global_list(pci);
+fail0:
+	mutex_unlock(&edac_pci_ctls_mutex);
+	return 1;
+}
+EXPORT_SYMBOL_GPL(edac_pci_add_device);
+
+/*
+ * edac_pci_del_device()
+ * 	Remove sysfs entries for specified edac_pci structure and
+ * 	then remove edac_pci structure from global list
+ *
+ * @dev:
+ * 	Pointer to 'struct device' representing edac_pci structure
+ * 	to remove
+ *
+ * Return:
+ * 	Pointer to removed edac_pci structure,
+ * 	or NULL if device not found
+ */
+struct edac_pci_ctl_info *edac_pci_del_device(struct device *dev)
+{
+	struct edac_pci_ctl_info *pci;
+
+	edac_dbg(0, "\n");
+
+	mutex_lock(&edac_pci_ctls_mutex);
+
+	/* ensure the control struct is on the global list
+	 * if not, then leave
+	 */
+	pci = find_edac_pci_by_dev(dev);
+	if (pci  == NULL) {
+		mutex_unlock(&edac_pci_ctls_mutex);
+		return NULL;
+	}
+
+	pci->op_state = OP_OFFLINE;
+
+	del_edac_pci_from_global_list(pci);
+
+	mutex_unlock(&edac_pci_ctls_mutex);
+
+	/* stop the workq timer */
+	edac_pci_workq_teardown(pci);
+
+	edac_printk(KERN_INFO, EDAC_PCI,
+		"Removed device %d for %s %s: DEV %s\n",
+		pci->pci_idx, pci->mod_name, pci->ctl_name, edac_dev_name(pci));
+
+	return pci;
+}
+EXPORT_SYMBOL_GPL(edac_pci_del_device);
+
+/*
+ * edac_pci_generic_check
+ *
+ *	a Generic parity check API
+ */
+static void edac_pci_generic_check(struct edac_pci_ctl_info *pci)
+{
+	edac_dbg(4, "\n");
+	edac_pci_do_parity_check();
+}
+
+/* free running instance index counter */
+static int edac_pci_idx;
+#define EDAC_PCI_GENCTL_NAME	"EDAC PCI controller"
+
+struct edac_pci_gen_data {
+	int edac_idx;
+};
+
+/*
+ * edac_pci_create_generic_ctl
+ *
+ *	A generic constructor for a PCI parity polling device
+ *	Some systems have more than one domain of PCI busses.
+ *	For systems with one domain, then this API will
+ *	provide for a generic poller.
+ *
+ *	This routine calls the edac_pci_alloc_ctl_info() for
+ *	the generic device, with default values
+ */
+struct edac_pci_ctl_info *edac_pci_create_generic_ctl(struct device *dev,
+						const char *mod_name)
+{
+	struct edac_pci_ctl_info *pci;
+	struct edac_pci_gen_data *pdata;
+
+	pci = edac_pci_alloc_ctl_info(sizeof(*pdata), EDAC_PCI_GENCTL_NAME);
+	if (!pci)
+		return NULL;
+
+	pdata = pci->pvt_info;
+	pci->dev = dev;
+	dev_set_drvdata(pci->dev, pci);
+	pci->dev_name = pci_name(to_pci_dev(dev));
+
+	pci->mod_name = mod_name;
+	pci->ctl_name = EDAC_PCI_GENCTL_NAME;
+	if (edac_op_state == EDAC_OPSTATE_POLL)
+		pci->edac_check = edac_pci_generic_check;
+
+	pdata->edac_idx = edac_pci_idx++;
+
+	if (edac_pci_add_device(pci, pdata->edac_idx) > 0) {
+		edac_dbg(3, "failed edac_pci_add_device()\n");
+		edac_pci_free_ctl_info(pci);
+		return NULL;
+	}
+
+	return pci;
+}
+EXPORT_SYMBOL_GPL(edac_pci_create_generic_ctl);
+
+/*
+ * edac_pci_release_generic_ctl
+ *
+ *	The release function of a generic EDAC PCI polling device
+ */
+void edac_pci_release_generic_ctl(struct edac_pci_ctl_info *pci)
+{
+	edac_dbg(0, "pci mod=%s\n", pci->mod_name);
+
+	edac_pci_del_device(pci->dev);
+	edac_pci_free_ctl_info(pci);
+}
+EXPORT_SYMBOL_GPL(edac_pci_release_generic_ctl);