blob: 0c767c561dc99495bffd172d61a0ca063a0c3145 [file] [log] [blame]
/*
* PowerNV OPAL Dump Interface
*
* 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/kobject.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/pagemap.h>
#include <linux/delay.h>
#include <asm/opal.h>
#define DUMP_TYPE_FSP 0x01
struct dump_obj {
struct kobject kobj;
struct bin_attribute dump_attr;
uint32_t id; /* becomes object name */
uint32_t type;
uint32_t size;
char *buffer;
};
#define to_dump_obj(x) container_of(x, struct dump_obj, kobj)
struct dump_attribute {
struct attribute attr;
ssize_t (*show)(struct dump_obj *dump, struct dump_attribute *attr,
char *buf);
ssize_t (*store)(struct dump_obj *dump, struct dump_attribute *attr,
const char *buf, size_t count);
};
#define to_dump_attr(x) container_of(x, struct dump_attribute, attr)
static ssize_t dump_id_show(struct dump_obj *dump_obj,
struct dump_attribute *attr,
char *buf)
{
return sprintf(buf, "0x%x\n", dump_obj->id);
}
static const char* dump_type_to_string(uint32_t type)
{
switch (type) {
case 0x01: return "SP Dump";
case 0x02: return "System/Platform Dump";
case 0x03: return "SMA Dump";
default: return "unknown";
}
}
static ssize_t dump_type_show(struct dump_obj *dump_obj,
struct dump_attribute *attr,
char *buf)
{
return sprintf(buf, "0x%x %s\n", dump_obj->type,
dump_type_to_string(dump_obj->type));
}
static ssize_t dump_ack_show(struct dump_obj *dump_obj,
struct dump_attribute *attr,
char *buf)
{
return sprintf(buf, "ack - acknowledge dump\n");
}
/*
* Send acknowledgement to OPAL
*/
static int64_t dump_send_ack(uint32_t dump_id)
{
int rc;
rc = opal_dump_ack(dump_id);
if (rc)
pr_warn("%s: Failed to send ack to Dump ID 0x%x (%d)\n",
__func__, dump_id, rc);
return rc;
}
static void delay_release_kobj(void *kobj)
{
kobject_put((struct kobject *)kobj);
}
static ssize_t dump_ack_store(struct dump_obj *dump_obj,
struct dump_attribute *attr,
const char *buf,
size_t count)
{
dump_send_ack(dump_obj->id);
sysfs_schedule_callback(&dump_obj->kobj, delay_release_kobj,
&dump_obj->kobj, THIS_MODULE);
return count;
}
/* Attributes of a dump
* The binary attribute of the dump itself is dynamic
* due to the dynamic size of the dump
*/
static struct dump_attribute id_attribute =
__ATTR(id, 0666, dump_id_show, NULL);
static struct dump_attribute type_attribute =
__ATTR(type, 0666, dump_type_show, NULL);
static struct dump_attribute ack_attribute =
__ATTR(acknowledge, 0660, dump_ack_show, dump_ack_store);
static ssize_t init_dump_show(struct dump_obj *dump_obj,
struct dump_attribute *attr,
char *buf)
{
return sprintf(buf, "1 - initiate dump\n");
}
static int64_t dump_fips_init(uint8_t type)
{
int rc;
rc = opal_dump_init(type);
if (rc)
pr_warn("%s: Failed to initiate FipS dump (%d)\n",
__func__, rc);
return rc;
}
static ssize_t init_dump_store(struct dump_obj *dump_obj,
struct dump_attribute *attr,
const char *buf,
size_t count)
{
dump_fips_init(DUMP_TYPE_FSP);
pr_info("%s: Initiated FSP dump\n", __func__);
return count;
}
static struct dump_attribute initiate_attribute =
__ATTR(initiate_dump, 0600, init_dump_show, init_dump_store);
static struct attribute *initiate_attrs[] = {
&initiate_attribute.attr,
NULL,
};
static struct attribute_group initiate_attr_group = {
.attrs = initiate_attrs,
};
static struct kset *dump_kset;
static ssize_t dump_attr_show(struct kobject *kobj,
struct attribute *attr,
char *buf)
{
struct dump_attribute *attribute;
struct dump_obj *dump;
attribute = to_dump_attr(attr);
dump = to_dump_obj(kobj);
if (!attribute->show)
return -EIO;
return attribute->show(dump, attribute, buf);
}
static ssize_t dump_attr_store(struct kobject *kobj,
struct attribute *attr,
const char *buf, size_t len)
{
struct dump_attribute *attribute;
struct dump_obj *dump;
attribute = to_dump_attr(attr);
dump = to_dump_obj(kobj);
if (!attribute->store)
return -EIO;
return attribute->store(dump, attribute, buf, len);
}
static const struct sysfs_ops dump_sysfs_ops = {
.show = dump_attr_show,
.store = dump_attr_store,
};
static void dump_release(struct kobject *kobj)
{
struct dump_obj *dump;
dump = to_dump_obj(kobj);
vfree(dump->buffer);
kfree(dump);
}
static struct attribute *dump_default_attrs[] = {
&id_attribute.attr,
&type_attribute.attr,
&ack_attribute.attr,
NULL,
};
static struct kobj_type dump_ktype = {
.sysfs_ops = &dump_sysfs_ops,
.release = &dump_release,
.default_attrs = dump_default_attrs,
};
static void free_dump_sg_list(struct opal_sg_list *list)
{
struct opal_sg_list *sg1;
while (list) {
sg1 = list->next;
kfree(list);
list = sg1;
}
list = NULL;
}
static struct opal_sg_list *dump_data_to_sglist(struct dump_obj *dump)
{
struct opal_sg_list *sg1, *list = NULL;
void *addr;
int64_t size;
addr = dump->buffer;
size = dump->size;
sg1 = kzalloc(PAGE_SIZE, GFP_KERNEL);
if (!sg1)
goto nomem;
list = sg1;
sg1->num_entries = 0;
while (size > 0) {
/* Translate virtual address to physical address */
sg1->entry[sg1->num_entries].data =
(void *)(vmalloc_to_pfn(addr) << PAGE_SHIFT);
if (size > PAGE_SIZE)
sg1->entry[sg1->num_entries].length = PAGE_SIZE;
else
sg1->entry[sg1->num_entries].length = size;
sg1->num_entries++;
if (sg1->num_entries >= SG_ENTRIES_PER_NODE) {
sg1->next = kzalloc(PAGE_SIZE, GFP_KERNEL);
if (!sg1->next)
goto nomem;
sg1 = sg1->next;
sg1->num_entries = 0;
}
addr += PAGE_SIZE;
size -= PAGE_SIZE;
}
return list;
nomem:
pr_err("%s : Failed to allocate memory\n", __func__);
free_dump_sg_list(list);
return NULL;
}
static void sglist_to_phy_addr(struct opal_sg_list *list)
{
struct opal_sg_list *sg, *next;
for (sg = list; sg; sg = next) {
next = sg->next;
/* Don't translate NULL pointer for last entry */
if (sg->next)
sg->next = (struct opal_sg_list *)__pa(sg->next);
else
sg->next = NULL;
/* Convert num_entries to length */
sg->num_entries =
sg->num_entries * sizeof(struct opal_sg_entry) + 16;
}
}
static int64_t dump_read_info(uint32_t *id, uint32_t *size, uint32_t *type)
{
int rc;
*type = 0xffffffff;
rc = opal_dump_info2(id, size, type);
if (rc == OPAL_PARAMETER)
rc = opal_dump_info(id, size);
if (rc)
pr_warn("%s: Failed to get dump info (%d)\n",
__func__, rc);
return rc;
}
static int64_t dump_read_data(struct dump_obj *dump)
{
struct opal_sg_list *list;
uint64_t addr;
int64_t rc;
/* Allocate memory */
dump->buffer = vzalloc(PAGE_ALIGN(dump->size));
if (!dump->buffer) {
pr_err("%s : Failed to allocate memory\n", __func__);
rc = -ENOMEM;
goto out;
}
/* Generate SG list */
list = dump_data_to_sglist(dump);
if (!list) {
rc = -ENOMEM;
goto out;
}
/* Translate sg list addr to real address */
sglist_to_phy_addr(list);
/* First entry address */
addr = __pa(list);
/* Fetch data */
rc = OPAL_BUSY_EVENT;
while (rc == OPAL_BUSY || rc == OPAL_BUSY_EVENT) {
rc = opal_dump_read(dump->id, addr);
if (rc == OPAL_BUSY_EVENT) {
opal_poll_events(NULL);
msleep(20);
}
}
if (rc != OPAL_SUCCESS && rc != OPAL_PARTIAL)
pr_warn("%s: Extract dump failed for ID 0x%x\n",
__func__, dump->id);
/* Free SG list */
free_dump_sg_list(list);
out:
return rc;
}
static ssize_t dump_attr_read(struct file *filep, struct kobject *kobj,
struct bin_attribute *bin_attr,
char *buffer, loff_t pos, size_t count)
{
ssize_t rc;
struct dump_obj *dump = to_dump_obj(kobj);
if (!dump->buffer) {
rc = dump_read_data(dump);
if (rc != OPAL_SUCCESS && rc != OPAL_PARTIAL) {
vfree(dump->buffer);
dump->buffer = NULL;
return -EIO;
}
if (rc == OPAL_PARTIAL) {
/* On a partial read, we just return EIO
* and rely on userspace to ask us to try
* again.
*/
pr_info("%s: Platform dump partially read.ID = 0x%x\n",
__func__, dump->id);
return -EIO;
}
}
memcpy(buffer, dump->buffer + pos, count);
/* You may think we could free the dump buffer now and retrieve
* it again later if needed, but due to current firmware limitation,
* that's not the case. So, once read into userspace once,
* we keep the dump around until it's acknowledged by userspace.
*/
return count;
}
static struct dump_obj *create_dump_obj(uint32_t id, size_t size,
uint32_t type)
{
struct dump_obj *dump;
int rc;
dump = kzalloc(sizeof(*dump), GFP_KERNEL);
if (!dump)
return NULL;
dump->kobj.kset = dump_kset;
kobject_init(&dump->kobj, &dump_ktype);
sysfs_bin_attr_init(&dump->dump_attr);
dump->dump_attr.attr.name = "dump";
dump->dump_attr.attr.mode = 0400;
dump->dump_attr.size = size;
dump->dump_attr.read = dump_attr_read;
dump->id = id;
dump->size = size;
dump->type = type;
rc = kobject_add(&dump->kobj, NULL, "0x%x-0x%x", type, id);
if (rc) {
kobject_put(&dump->kobj);
return NULL;
}
rc = sysfs_create_bin_file(&dump->kobj, &dump->dump_attr);
if (rc) {
kobject_put(&dump->kobj);
return NULL;
}
pr_info("%s: New platform dump. ID = 0x%x Size %u\n",
__func__, dump->id, dump->size);
kobject_uevent(&dump->kobj, KOBJ_ADD);
return dump;
}
static int process_dump(void)
{
int rc;
uint32_t dump_id, dump_size, dump_type;
struct dump_obj *dump;
char name[22];
rc = dump_read_info(&dump_id, &dump_size, &dump_type);
if (rc != OPAL_SUCCESS)
return rc;
sprintf(name, "0x%x-0x%x", dump_type, dump_id);
/* we may get notified twice, let's handle
* that gracefully and not create two conflicting
* entries.
*/
if (kset_find_obj(dump_kset, name))
return 0;
dump = create_dump_obj(dump_id, dump_size, dump_type);
if (!dump)
return -1;
return 0;
}
static void dump_work_fn(struct work_struct *work)
{
process_dump();
}
static DECLARE_WORK(dump_work, dump_work_fn);
static void schedule_process_dump(void)
{
schedule_work(&dump_work);
}
/*
* New dump available notification
*
* Once we get notification, we add sysfs entries for it.
* We only fetch the dump on demand, and create sysfs asynchronously.
*/
static int dump_event(struct notifier_block *nb,
unsigned long events, void *change)
{
if (events & OPAL_EVENT_DUMP_AVAIL)
schedule_process_dump();
return 0;
}
static struct notifier_block dump_nb = {
.notifier_call = dump_event,
.next = NULL,
.priority = 0
};
void __init opal_platform_dump_init(void)
{
int rc;
dump_kset = kset_create_and_add("dump", NULL, opal_kobj);
if (!dump_kset) {
pr_warn("%s: Failed to create dump kset\n", __func__);
return;
}
rc = sysfs_create_group(&dump_kset->kobj, &initiate_attr_group);
if (rc) {
pr_warn("%s: Failed to create initiate dump attr group\n",
__func__);
kobject_put(&dump_kset->kobj);
return;
}
rc = opal_notifier_register(&dump_nb);
if (rc) {
pr_warn("%s: Can't register OPAL event notifier (%d)\n",
__func__, rc);
return;
}
opal_dump_resend_notification();
}