[linux.git] / arch / powerpc / platforms / powernv / opal-elog.c

/*
 * Error log support on PowerNV.
 *
 * Copyright 2013,2014 IBM Corp.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version
 * 2 of the License, or (at your option) any later version.
 */
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/of.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <linux/fs.h>
#include <linux/vmalloc.h>
#include <linux/fcntl.h>
#include <linux/kobject.h>
#include <asm/uaccess.h>
#include <asm/opal.h>

struct elog_obj {
	struct kobject kobj;
	struct bin_attribute raw_attr;
	uint64_t id;
	uint64_t type;
	size_t size;
	char *buffer;
};
#define to_elog_obj(x) container_of(x, struct elog_obj, kobj)

struct elog_attribute {
	struct attribute attr;
	ssize_t (*show)(struct elog_obj *elog, struct elog_attribute *attr,
			char *buf);
	ssize_t (*store)(struct elog_obj *elog, struct elog_attribute *attr,
			 const char *buf, size_t count);
};
#define to_elog_attr(x) container_of(x, struct elog_attribute, attr)

static ssize_t elog_id_show(struct elog_obj *elog_obj,
			    struct elog_attribute *attr,
			    char *buf)
{
	return sprintf(buf, "0x%llx\n", elog_obj->id);
}

static const char *elog_type_to_string(uint64_t type)
{
	switch (type) {
	case 0: return "PEL";
	default: return "unknown";
	}
}

static ssize_t elog_type_show(struct elog_obj *elog_obj,
			      struct elog_attribute *attr,
			      char *buf)
{
	return sprintf(buf, "0x%llx %s\n",
		       elog_obj->type,
		       elog_type_to_string(elog_obj->type));
}

static ssize_t elog_ack_show(struct elog_obj *elog_obj,
			     struct elog_attribute *attr,
			     char *buf)
{
	return sprintf(buf, "ack - acknowledge log message\n");
}

static ssize_t elog_ack_store(struct elog_obj *elog_obj,
			      struct elog_attribute *attr,
			      const char *buf,
			      size_t count)
{
	opal_send_ack_elog(elog_obj->id);
	sysfs_remove_file_self(&elog_obj->kobj, &attr->attr);
	kobject_put(&elog_obj->kobj);
	return count;
}

static struct elog_attribute id_attribute =
	__ATTR(id, S_IRUGO, elog_id_show, NULL);
static struct elog_attribute type_attribute =
	__ATTR(type, S_IRUGO, elog_type_show, NULL);
static struct elog_attribute ack_attribute =
	__ATTR(acknowledge, 0660, elog_ack_show, elog_ack_store);

static struct kset *elog_kset;

static ssize_t elog_attr_show(struct kobject *kobj,
			      struct attribute *attr,
			      char *buf)
{
	struct elog_attribute *attribute;
	struct elog_obj *elog;

	attribute = to_elog_attr(attr);
	elog = to_elog_obj(kobj);

	if (!attribute->show)
		return -EIO;

	return attribute->show(elog, attribute, buf);
}

static ssize_t elog_attr_store(struct kobject *kobj,
			       struct attribute *attr,
			       const char *buf, size_t len)
{
	struct elog_attribute *attribute;
	struct elog_obj *elog;

	attribute = to_elog_attr(attr);
	elog = to_elog_obj(kobj);

	if (!attribute->store)
		return -EIO;

	return attribute->store(elog, attribute, buf, len);
}

static const struct sysfs_ops elog_sysfs_ops = {
	.show = elog_attr_show,
	.store = elog_attr_store,
};

static void elog_release(struct kobject *kobj)
{
	struct elog_obj *elog;

	elog = to_elog_obj(kobj);
	kfree(elog->buffer);
	kfree(elog);
}

static struct attribute *elog_default_attrs[] = {
	&id_attribute.attr,
	&type_attribute.attr,
	&ack_attribute.attr,
	NULL,
};

static struct kobj_type elog_ktype = {
	.sysfs_ops = &elog_sysfs_ops,
	.release = &elog_release,
	.default_attrs = elog_default_attrs,
};

/* Maximum size of a single log on FSP is 16KB */
#define OPAL_MAX_ERRLOG_SIZE	16384

static ssize_t raw_attr_read(struct file *filep, struct kobject *kobj,
			     struct bin_attribute *bin_attr,
			     char *buffer, loff_t pos, size_t count)
{
	int opal_rc;

	struct elog_obj *elog = to_elog_obj(kobj);

	/* We may have had an error reading before, so let's retry */
	if (!elog->buffer) {
		elog->buffer = kzalloc(elog->size, GFP_KERNEL);
		if (!elog->buffer)
			return -EIO;

		opal_rc = opal_read_elog(__pa(elog->buffer),
					 elog->size, elog->id);
		if (opal_rc != OPAL_SUCCESS) {
			pr_err("ELOG: log read failed for log-id=%llx\n",
			       elog->id);
			kfree(elog->buffer);
			elog->buffer = NULL;
			return -EIO;
		}
	}

	memcpy(buffer, elog->buffer + pos, count);

	return count;
}

static struct elog_obj *create_elog_obj(uint64_t id, size_t size, uint64_t type)
{
	struct elog_obj *elog;
	int rc;

	elog = kzalloc(sizeof(*elog), GFP_KERNEL);
	if (!elog)
		return NULL;

	elog->kobj.kset = elog_kset;

	kobject_init(&elog->kobj, &elog_ktype);

	sysfs_bin_attr_init(&elog->raw_attr);

	elog->raw_attr.attr.name = "raw";
	elog->raw_attr.attr.mode = 0400;
	elog->raw_attr.size = size;
	elog->raw_attr.read = raw_attr_read;

	elog->id = id;
	elog->size = size;
	elog->type = type;

	elog->buffer = kzalloc(elog->size, GFP_KERNEL);

	if (elog->buffer) {
		rc = opal_read_elog(__pa(elog->buffer),
					 elog->size, elog->id);
		if (rc != OPAL_SUCCESS) {
			pr_err("ELOG: log read failed for log-id=%llx\n",
			       elog->id);
			kfree(elog->buffer);
			elog->buffer = NULL;
		}
	}

	rc = kobject_add(&elog->kobj, NULL, "0x%llx", id);
	if (rc) {
		kobject_put(&elog->kobj);
		return NULL;
	}

	rc = sysfs_create_bin_file(&elog->kobj, &elog->raw_attr);
	if (rc) {
		kobject_put(&elog->kobj);
		return NULL;
	}

	kobject_uevent(&elog->kobj, KOBJ_ADD);

	return elog;
}

static irqreturn_t elog_event(int irq, void *data)
{
	__be64 size;
	__be64 id;
	__be64 type;
	uint64_t elog_size;
	uint64_t log_id;
	uint64_t elog_type;
	int rc;
	char name[2+16+1];

	rc = opal_get_elog_size(&id, &size, &type);
	if (rc != OPAL_SUCCESS) {
		pr_err("ELOG: OPAL log info read failed\n");
		return IRQ_HANDLED;
	}

	elog_size = be64_to_cpu(size);
	log_id = be64_to_cpu(id);
	elog_type = be64_to_cpu(type);

	WARN_ON(elog_size > OPAL_MAX_ERRLOG_SIZE);

	if (elog_size >= OPAL_MAX_ERRLOG_SIZE)
		elog_size  =  OPAL_MAX_ERRLOG_SIZE;

	sprintf(name, "0x%llx", log_id);

	/* we may get notified twice, let's handle
	 * that gracefully and not create two conflicting
	 * entries.
	 */
	if (kset_find_obj(elog_kset, name))
		return IRQ_HANDLED;

	create_elog_obj(log_id, elog_size, elog_type);

	return IRQ_HANDLED;
}

int __init opal_elog_init(void)
{
	int rc = 0, irq;

	/* ELOG not supported by firmware */
	if (!opal_check_token(OPAL_ELOG_READ))
		return -1;

	elog_kset = kset_create_and_add("elog", NULL, opal_kobj);
	if (!elog_kset) {
		pr_warn("%s: failed to create elog kset\n", __func__);
		return -1;
	}

	irq = opal_event_request(ilog2(OPAL_EVENT_ERROR_LOG_AVAIL));
	if (!irq) {
		pr_err("%s: Can't register OPAL event irq (%d)\n",
		       __func__, irq);
		return irq;
	}

	rc = request_threaded_irq(irq, NULL, elog_event,
			IRQF_TRIGGER_HIGH | IRQF_ONESHOT, "opal-elog", NULL);
	if (rc) {
		pr_err("%s: Can't request OPAL event irq (%d)\n",
		       __func__, rc);
		return rc;
	}

	/* We are now ready to pull error logs from opal. */
	if (opal_check_token(OPAL_ELOG_RESEND))
		opal_resend_pending_logs();

	return 0;
}
Commit	Line	Data
774fea1a SS	1	/*
	2	* Error log support on PowerNV.
	3	*
	4	* Copyright 2013,2014 IBM Corp.
	5	*
	6	* This program is free software; you can redistribute it and/or
	7	* modify it under the terms of the GNU General Public License
	8	* as published by the Free Software Foundation; either version
	9	* 2 of the License, or (at your option) any later version.
	10	*/
	11	#include <linux/kernel.h>
	12	#include <linux/init.h>
74159a70	13	#include <linux/interrupt.h>
774fea1a SS	14	#include <linux/of.h>
	15	#include <linux/slab.h>
	16	#include <linux/sysfs.h>
	17	#include <linux/fs.h>
	18	#include <linux/vmalloc.h>
	19	#include <linux/fcntl.h>
	20	#include <linux/kobject.h>
	21	#include <asm/uaccess.h>
	22	#include <asm/opal.h>
	23
	24	struct elog_obj {
	25	struct kobject kobj;
	26	struct bin_attribute raw_attr;
	27	uint64_t id;
	28	uint64_t type;
	29	size_t size;
	30	char *buffer;
	31	};
	32	#define to_elog_obj(x) container_of(x, struct elog_obj, kobj)
	33
	34	struct elog_attribute {
	35	struct attribute attr;
	36	ssize_t (show)(struct elog_obj elog, struct elog_attribute *attr,
	37	char *buf);
	38	ssize_t (store)(struct elog_obj elog, struct elog_attribute *attr,
	39	const char *buf, size_t count);
	40	};
	41	#define to_elog_attr(x) container_of(x, struct elog_attribute, attr)
	42
	43	static ssize_t elog_id_show(struct elog_obj *elog_obj,
	44	struct elog_attribute *attr,
	45	char *buf)
	46	{
	47	return sprintf(buf, "0x%llx\n", elog_obj->id);
	48	}
	49
	50	static const char *elog_type_to_string(uint64_t type)
	51	{
	52	switch (type) {
	53	case 0: return "PEL";
	54	default: return "unknown";
	55	}
	56	}
	57
	58	static ssize_t elog_type_show(struct elog_obj *elog_obj,
	59	struct elog_attribute *attr,
	60	char *buf)
	61	{
	62	return sprintf(buf, "0x%llx %s\n",
	63	elog_obj->type,
	64	elog_type_to_string(elog_obj->type));
	65	}
	66
	67	static ssize_t elog_ack_show(struct elog_obj *elog_obj,
	68	struct elog_attribute *attr,
	69	char *buf)
	70	{
	71	return sprintf(buf, "ack - acknowledge log message\n");
	72	}
	73
774fea1a SS	74	static ssize_t elog_ack_store(struct elog_obj *elog_obj,
	75	struct elog_attribute *attr,
	76	const char *buf,
	77	size_t count)
	78	{
	79	opal_send_ack_elog(elog_obj->id);
cc4f265a SS	80	sysfs_remove_file_self(&elog_obj->kobj, &attr->attr);
cc4f265a SS	81	kobject_put(&elog_obj->kobj);
774fea1a SS	82	return count;
	83	}
	84
	85	static struct elog_attribute id_attribute =
6656c21c	86	__ATTR(id, S_IRUGO, elog_id_show, NULL);
774fea1a	87	static struct elog_attribute type_attribute =
6656c21c	88	__ATTR(type, S_IRUGO, elog_type_show, NULL);
774fea1a SS	89	static struct elog_attribute ack_attribute =
	90	__ATTR(acknowledge, 0660, elog_ack_show, elog_ack_store);
	91
	92	static struct kset *elog_kset;
	93
	94	static ssize_t elog_attr_show(struct kobject *kobj,
	95	struct attribute *attr,
	96	char *buf)
	97	{
	98	struct elog_attribute *attribute;
	99	struct elog_obj *elog;
	100
	101	attribute = to_elog_attr(attr);
	102	elog = to_elog_obj(kobj);
	103
	104	if (!attribute->show)
	105	return -EIO;
	106
	107	return attribute->show(elog, attribute, buf);
	108	}
	109
	110	static ssize_t elog_attr_store(struct kobject *kobj,
	111	struct attribute *attr,
	112	const char *buf, size_t len)
	113	{
	114	struct elog_attribute *attribute;
	115	struct elog_obj *elog;
	116
	117	attribute = to_elog_attr(attr);
	118	elog = to_elog_obj(kobj);
	119
	120	if (!attribute->store)
	121	return -EIO;
	122
	123	return attribute->store(elog, attribute, buf, len);
	124	}
	125
	126	static const struct sysfs_ops elog_sysfs_ops = {
	127	.show = elog_attr_show,
	128	.store = elog_attr_store,
	129	};
	130
	131	static void elog_release(struct kobject *kobj)
	132	{
	133	struct elog_obj *elog;
	134
	135	elog = to_elog_obj(kobj);
	136	kfree(elog->buffer);
	137	kfree(elog);
	138	}
	139
	140	static struct attribute *elog_default_attrs[] = {
	141	&id_attribute.attr,
	142	&type_attribute.attr,
	143	&ack_attribute.attr,
	144	NULL,
	145	};
	146
	147	static struct kobj_type elog_ktype = {
	148	.sysfs_ops = &elog_sysfs_ops,
	149	.release = &elog_release,
	150	.default_attrs = elog_default_attrs,
	151	};
	152
153	/* Maximum size of a single log on FSP is 16KB */
154	#define OPAL_MAX_ERRLOG_SIZE 16384
155
156	static ssize_t raw_attr_read(struct file filep, struct kobject kobj,
157	struct bin_attribute *bin_attr,
158	char *buffer, loff_t pos, size_t count)
159	{
160	int opal_rc;
161
162	struct elog_obj *elog = to_elog_obj(kobj);
163
164	/* We may have had an error reading before, so let's retry */
165	if (!elog->buffer) {
166	elog->buffer = kzalloc(elog->size, GFP_KERNEL);
167	if (!elog->buffer)
168	return -EIO;
169
170	opal_rc = opal_read_elog(__pa(elog->buffer),
171	elog->size, elog->id);
172	if (opal_rc != OPAL_SUCCESS) {
173	pr_err("ELOG: log read failed for log-id=%llx\n",
174	elog->id);
175	kfree(elog->buffer);
176	elog->buffer = NULL;
177	return -EIO;
178	}
179	}
180
181	memcpy(buffer, elog->buffer + pos, count);
182
183	return count;
184	}
185
186	static struct elog_obj *create_elog_obj(uint64_t id, size_t size, uint64_t type)
187	{
188	struct elog_obj *elog;
189	int rc;
190
191	elog = kzalloc(sizeof(*elog), GFP_KERNEL);
192	if (!elog)
193	return NULL;
194
195	elog->kobj.kset = elog_kset;
196
197	kobject_init(&elog->kobj, &elog_ktype);
198
199	sysfs_bin_attr_init(&elog->raw_attr);
200
201	elog->raw_attr.attr.name = "raw";
202	elog->raw_attr.attr.mode = 0400;
203	elog->raw_attr.size = size;
204	elog->raw_attr.read = raw_attr_read;
205
206	elog->id = id;
207	elog->size = size;
208	elog->type = type;
209
210	elog->buffer = kzalloc(elog->size, GFP_KERNEL);
211
212	if (elog->buffer) {
213	rc = opal_read_elog(__pa(elog->buffer),
214	elog->size, elog->id);
215	if (rc != OPAL_SUCCESS) {
216	pr_err("ELOG: log read failed for log-id=%llx\n",
217	elog->id);
218	kfree(elog->buffer);
219	elog->buffer = NULL;
220	}
221	}
222
223	rc = kobject_add(&elog->kobj, NULL, "0x%llx", id);
224	if (rc) {
225	kobject_put(&elog->kobj);
226	return NULL;
227	}
228
229	rc = sysfs_create_bin_file(&elog->kobj, &elog->raw_attr);
230	if (rc) {
231	kobject_put(&elog->kobj);
232	return NULL;
233	}
234
235	kobject_uevent(&elog->kobj, KOBJ_ADD);
236
237	return elog;
238	}
239
a8956a7b	240	static irqreturn_t elog_event(int irq, void *data)
774fea1a	241	{
14ad0c58 AB	242	__be64 size;
	243	__be64 id;
	244	__be64 type;
2bad7423	245	uint64_t elog_size;
774fea1a SS	246	uint64_t log_id;
	247	uint64_t elog_type;
	248	int rc;
	249	char name[2+16+1];
	250
14ad0c58	251	rc = opal_get_elog_size(&id, &size, &type);
774fea1a	252	if (rc != OPAL_SUCCESS) {
fa952c54	253	pr_err("ELOG: OPAL log info read failed\n");
a8956a7b	254	return IRQ_HANDLED;
774fea1a SS	255	}
774fea1a SS	256
14ad0c58 AB	257	elog_size = be64_to_cpu(size);
	258	log_id = be64_to_cpu(id);
	259	elog_type = be64_to_cpu(type);
	260
fa952c54	261	WARN_ON(elog_size > OPAL_MAX_ERRLOG_SIZE);
774fea1a SS	262
	263	if (elog_size >= OPAL_MAX_ERRLOG_SIZE)
	264	elog_size = OPAL_MAX_ERRLOG_SIZE;
	265
	266	sprintf(name, "0x%llx", log_id);
	267
	268	/* we may get notified twice, let's handle
	269	* that gracefully and not create two conflicting
	270	* entries.
	271	*/
	272	if (kset_find_obj(elog_kset, name))
a8956a7b	273	return IRQ_HANDLED;
774fea1a SS	274
774fea1a SS	275	create_elog_obj(log_id, elog_size, elog_type);
774fea1a	276
74159a70	277	return IRQ_HANDLED;
774fea1a SS	278	}
774fea1a SS	279
774fea1a SS	280	int __init opal_elog_init(void)
774fea1a SS	281	{
74159a70	282	int rc = 0, irq;
774fea1a	283
7dc992ec MN	284	/* ELOG not supported by firmware */
	285	if (!opal_check_token(OPAL_ELOG_READ))
	286	return -1;
	287
774fea1a SS	288	elog_kset = kset_create_and_add("elog", NULL, opal_kobj);
	289	if (!elog_kset) {
	290	pr_warn("%s: failed to create elog kset\n", __func__);
	291	return -1;
	292	}
	293
74159a70 AP	294	irq = opal_event_request(ilog2(OPAL_EVENT_ERROR_LOG_AVAIL));
	295	if (!irq) {
	296	pr_err("%s: Can't register OPAL event irq (%d)\n",
	297	__func__, irq);
	298	return irq;
	299	}
	300
a8956a7b AP	301	rc = request_threaded_irq(irq, NULL, elog_event,
a8956a7b AP	302	IRQF_TRIGGER_HIGH \| IRQF_ONESHOT, "opal-elog", NULL);
774fea1a	303	if (rc) {
74159a70 AP	304	pr_err("%s: Can't request OPAL event irq (%d)\n",
74159a70 AP	305	__func__, rc);
774fea1a SS	306	return rc;
	307	}
	308
	309	/* We are now ready to pull error logs from opal. */
fc81de63 SS	310	if (opal_check_token(OPAL_ELOG_RESEND))
fc81de63 SS	311	opal_resend_pending_logs();
774fea1a SS	312
	313	return 0;
	314	}