| /* |
| * 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 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_remove_file_self(&dump_obj->kobj, &attr->attr); |
| kobject_put(&dump_obj->kobj); |
| 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 int64_t dump_read_info(uint32_t *dump_id, uint32_t *dump_size, uint32_t *dump_type) |
| { |
| __be32 id, size, type; |
| int rc; |
| |
| type = cpu_to_be32(0xffffffff); |
| |
| rc = opal_dump_info2(&id, &size, &type); |
| if (rc == OPAL_PARAMETER) |
| rc = opal_dump_info(&id, &size); |
| |
| *dump_id = be32_to_cpu(id); |
| *dump_size = be32_to_cpu(size); |
| *dump_type = be32_to_cpu(type); |
| |
| 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 = opal_vmalloc_to_sg_list(dump->buffer, dump->size); |
| if (!list) { |
| rc = -ENOMEM; |
| goto out; |
| } |
| |
| /* 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 */ |
| opal_free_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(); |
| } |