--- /dev/null
+/*
+ * 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();
+}
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