Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1354 insertions, 0 deletions

diff --git a/arch/sparc/kernel/mdesc.c b/arch/sparc/kernel/mdesc.c
new file mode 100644
index 000000000..ecec6a616
--- /dev/null
+++ b/arch/sparc/kernel/mdesc.c
@@ -0,0 +1,1354 @@
+// SPDX-License-Identifier: GPL-2.0
+/* mdesc.c: Sun4V machine description handling.
+ *
+ * Copyright (C) 2007, 2008 David S. Miller <davem@davemloft.net>
+ */
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/memblock.h>
+#include <linux/log2.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+#include <linux/miscdevice.h>
+#include <linux/bootmem.h>
+#include <linux/export.h>
+#include <linux/refcount.h>
+
+#include <asm/cpudata.h>
+#include <asm/hypervisor.h>
+#include <asm/mdesc.h>
+#include <asm/prom.h>
+#include <linux/uaccess.h>
+#include <asm/oplib.h>
+#include <asm/smp.h>
+#include <asm/adi.h>
+
+/* Unlike the OBP device tree, the machine description is a full-on
+ * DAG.  An arbitrary number of ARCs are possible from one
+ * node to other nodes and thus we can't use the OBP device_node
+ * data structure to represent these nodes inside of the kernel.
+ *
+ * Actually, it isn't even a DAG, because there are back pointers
+ * which create cycles in the graph.
+ *
+ * mdesc_hdr and mdesc_elem describe the layout of the data structure
+ * we get from the Hypervisor.
+ */
+struct mdesc_hdr {
+	u32	version; /* Transport version */
+	u32	node_sz; /* node block size */
+	u32	name_sz; /* name block size */
+	u32	data_sz; /* data block size */
+	char	data[];
+} __attribute__((aligned(16)));
+
+struct mdesc_elem {
+	u8	tag;
+#define MD_LIST_END	0x00
+#define MD_NODE		0x4e
+#define MD_NODE_END	0x45
+#define MD_NOOP		0x20
+#define MD_PROP_ARC	0x61
+#define MD_PROP_VAL	0x76
+#define MD_PROP_STR	0x73
+#define MD_PROP_DATA	0x64
+	u8	name_len;
+	u16	resv;
+	u32	name_offset;
+	union {
+		struct {
+			u32	data_len;
+			u32	data_offset;
+		} data;
+		u64	val;
+	} d;
+};
+
+struct mdesc_mem_ops {
+	struct mdesc_handle *(*alloc)(unsigned int mdesc_size);
+	void (*free)(struct mdesc_handle *handle);
+};
+
+struct mdesc_handle {
+	struct list_head	list;
+	struct mdesc_mem_ops	*mops;
+	void			*self_base;
+	refcount_t		refcnt;
+	unsigned int		handle_size;
+	struct mdesc_hdr	mdesc;
+};
+
+typedef int (*mdesc_node_info_get_f)(struct mdesc_handle *, u64,
+				     union md_node_info *);
+typedef void (*mdesc_node_info_rel_f)(union md_node_info *);
+typedef bool (*mdesc_node_match_f)(union md_node_info *, union md_node_info *);
+
+struct md_node_ops {
+	char			*name;
+	mdesc_node_info_get_f	get_info;
+	mdesc_node_info_rel_f	rel_info;
+	mdesc_node_match_f	node_match;
+};
+
+static int get_vdev_port_node_info(struct mdesc_handle *md, u64 node,
+				   union md_node_info *node_info);
+static void rel_vdev_port_node_info(union md_node_info *node_info);
+static bool vdev_port_node_match(union md_node_info *a_node_info,
+				 union md_node_info *b_node_info);
+
+static int get_ds_port_node_info(struct mdesc_handle *md, u64 node,
+				 union md_node_info *node_info);
+static void rel_ds_port_node_info(union md_node_info *node_info);
+static bool ds_port_node_match(union md_node_info *a_node_info,
+			       union md_node_info *b_node_info);
+
+/* supported node types which can be registered */
+static struct md_node_ops md_node_ops_table[] = {
+	{"virtual-device-port", get_vdev_port_node_info,
+	 rel_vdev_port_node_info, vdev_port_node_match},
+	{"domain-services-port", get_ds_port_node_info,
+	 rel_ds_port_node_info, ds_port_node_match},
+	{NULL, NULL, NULL, NULL}
+};
+
+static void mdesc_get_node_ops(const char *node_name,
+			       mdesc_node_info_get_f *get_info_f,
+			       mdesc_node_info_rel_f *rel_info_f,
+			       mdesc_node_match_f *match_f)
+{
+	int i;
+
+	if (get_info_f)
+		*get_info_f = NULL;
+
+	if (rel_info_f)
+		*rel_info_f = NULL;
+
+	if (match_f)
+		*match_f = NULL;
+
+	if (!node_name)
+		return;
+
+	for (i = 0; md_node_ops_table[i].name != NULL; i++) {
+		if (strcmp(md_node_ops_table[i].name, node_name) == 0) {
+			if (get_info_f)
+				*get_info_f = md_node_ops_table[i].get_info;
+
+			if (rel_info_f)
+				*rel_info_f = md_node_ops_table[i].rel_info;
+
+			if (match_f)
+				*match_f = md_node_ops_table[i].node_match;
+
+			break;
+		}
+	}
+}
+
+static void mdesc_handle_init(struct mdesc_handle *hp,
+			      unsigned int handle_size,
+			      void *base)
+{
+	BUG_ON(((unsigned long)&hp->mdesc) & (16UL - 1));
+
+	memset(hp, 0, handle_size);
+	INIT_LIST_HEAD(&hp->list);
+	hp->self_base = base;
+	refcount_set(&hp->refcnt, 1);
+	hp->handle_size = handle_size;
+}
+
+static struct mdesc_handle * __init mdesc_memblock_alloc(unsigned int mdesc_size)
+{
+	unsigned int handle_size, alloc_size;
+	struct mdesc_handle *hp;
+	unsigned long paddr;
+
+	handle_size = (sizeof(struct mdesc_handle) -
+		       sizeof(struct mdesc_hdr) +
+		       mdesc_size);
+	alloc_size = PAGE_ALIGN(handle_size);
+
+	paddr = memblock_alloc(alloc_size, PAGE_SIZE);
+
+	hp = NULL;
+	if (paddr) {
+		hp = __va(paddr);
+		mdesc_handle_init(hp, handle_size, hp);
+	}
+	return hp;
+}
+
+static void __init mdesc_memblock_free(struct mdesc_handle *hp)
+{
+	unsigned int alloc_size;
+	unsigned long start;
+
+	BUG_ON(refcount_read(&hp->refcnt) != 0);
+	BUG_ON(!list_empty(&hp->list));
+
+	alloc_size = PAGE_ALIGN(hp->handle_size);
+	start = __pa(hp);
+	free_bootmem_late(start, alloc_size);
+}
+
+static struct mdesc_mem_ops memblock_mdesc_ops = {
+	.alloc = mdesc_memblock_alloc,
+	.free  = mdesc_memblock_free,
+};
+
+static struct mdesc_handle *mdesc_kmalloc(unsigned int mdesc_size)
+{
+	unsigned int handle_size;
+	struct mdesc_handle *hp;
+	unsigned long addr;
+	void *base;
+
+	handle_size = (sizeof(struct mdesc_handle) -
+		       sizeof(struct mdesc_hdr) +
+		       mdesc_size);
+	base = kmalloc(handle_size + 15, GFP_KERNEL | __GFP_RETRY_MAYFAIL);
+	if (!base)
+		return NULL;
+
+	addr = (unsigned long)base;
+	addr = (addr + 15UL) & ~15UL;
+	hp = (struct mdesc_handle *) addr;
+
+	mdesc_handle_init(hp, handle_size, base);
+
+	return hp;
+}
+
+static void mdesc_kfree(struct mdesc_handle *hp)
+{
+	BUG_ON(refcount_read(&hp->refcnt) != 0);
+	BUG_ON(!list_empty(&hp->list));
+
+	kfree(hp->self_base);
+}
+
+static struct mdesc_mem_ops kmalloc_mdesc_memops = {
+	.alloc = mdesc_kmalloc,
+	.free  = mdesc_kfree,
+};
+
+static struct mdesc_handle *mdesc_alloc(unsigned int mdesc_size,
+					struct mdesc_mem_ops *mops)
+{
+	struct mdesc_handle *hp = mops->alloc(mdesc_size);
+
+	if (hp)
+		hp->mops = mops;
+
+	return hp;
+}
+
+static void mdesc_free(struct mdesc_handle *hp)
+{
+	hp->mops->free(hp);
+}
+
+static struct mdesc_handle *cur_mdesc;
+static LIST_HEAD(mdesc_zombie_list);
+static DEFINE_SPINLOCK(mdesc_lock);
+
+struct mdesc_handle *mdesc_grab(void)
+{
+	struct mdesc_handle *hp;
+	unsigned long flags;
+
+	spin_lock_irqsave(&mdesc_lock, flags);
+	hp = cur_mdesc;
+	if (hp)
+		refcount_inc(&hp->refcnt);
+	spin_unlock_irqrestore(&mdesc_lock, flags);
+
+	return hp;
+}
+EXPORT_SYMBOL(mdesc_grab);
+
+void mdesc_release(struct mdesc_handle *hp)
+{
+	unsigned long flags;
+
+	spin_lock_irqsave(&mdesc_lock, flags);
+	if (refcount_dec_and_test(&hp->refcnt)) {
+		list_del_init(&hp->list);
+		hp->mops->free(hp);
+	}
+	spin_unlock_irqrestore(&mdesc_lock, flags);
+}
+EXPORT_SYMBOL(mdesc_release);
+
+static DEFINE_MUTEX(mdesc_mutex);
+static struct mdesc_notifier_client *client_list;
+
+void mdesc_register_notifier(struct mdesc_notifier_client *client)
+{
+	bool supported = false;
+	u64 node;
+	int i;
+
+	mutex_lock(&mdesc_mutex);
+
+	/* check to see if the node is supported for registration */
+	for (i = 0; md_node_ops_table[i].name != NULL; i++) {
+		if (strcmp(md_node_ops_table[i].name, client->node_name) == 0) {
+			supported = true;
+			break;
+		}
+	}
+
+	if (!supported) {
+		pr_err("MD: %s node not supported\n", client->node_name);
+		mutex_unlock(&mdesc_mutex);
+		return;
+	}
+
+	client->next = client_list;
+	client_list = client;
+
+	mdesc_for_each_node_by_name(cur_mdesc, node, client->node_name)
+		client->add(cur_mdesc, node, client->node_name);
+
+	mutex_unlock(&mdesc_mutex);
+}
+
+static const u64 *parent_cfg_handle(struct mdesc_handle *hp, u64 node)
+{
+	const u64 *id;
+	u64 a;
+
+	id = NULL;
+	mdesc_for_each_arc(a, hp, node, MDESC_ARC_TYPE_BACK) {
+		u64 target;
+
+		target = mdesc_arc_target(hp, a);
+		id = mdesc_get_property(hp, target,
+					"cfg-handle", NULL);
+		if (id)
+			break;
+	}
+
+	return id;
+}
+
+static int get_vdev_port_node_info(struct mdesc_handle *md, u64 node,
+				   union md_node_info *node_info)
+{
+	const u64 *parent_cfg_hdlp;
+	const char *name;
+	const u64 *idp;
+
+	/*
+	 * Virtual device nodes are distinguished by:
+	 * 1. "id" property
+	 * 2. "name" property
+	 * 3. parent node "cfg-handle" property
+	 */
+	idp = mdesc_get_property(md, node, "id", NULL);
+	name = mdesc_get_property(md, node, "name", NULL);
+	parent_cfg_hdlp = parent_cfg_handle(md, node);
+
+	if (!idp || !name || !parent_cfg_hdlp)
+		return -1;
+
+	node_info->vdev_port.id = *idp;
+	node_info->vdev_port.name = kstrdup_const(name, GFP_KERNEL);
+	if (!node_info->vdev_port.name)
+		return -1;
+	node_info->vdev_port.parent_cfg_hdl = *parent_cfg_hdlp;
+
+	return 0;
+}
+
+static void rel_vdev_port_node_info(union md_node_info *node_info)
+{
+	if (node_info && node_info->vdev_port.name) {
+		kfree_const(node_info->vdev_port.name);
+		node_info->vdev_port.name = NULL;
+	}
+}
+
+static bool vdev_port_node_match(union md_node_info *a_node_info,
+				 union md_node_info *b_node_info)
+{
+	if (a_node_info->vdev_port.id != b_node_info->vdev_port.id)
+		return false;
+
+	if (a_node_info->vdev_port.parent_cfg_hdl !=
+	    b_node_info->vdev_port.parent_cfg_hdl)
+		return false;
+
+	if (strncmp(a_node_info->vdev_port.name,
+		    b_node_info->vdev_port.name, MDESC_MAX_STR_LEN) != 0)
+		return false;
+
+	return true;
+}
+
+static int get_ds_port_node_info(struct mdesc_handle *md, u64 node,
+				 union md_node_info *node_info)
+{
+	const u64 *idp;
+
+	/* DS port nodes use the "id" property to distinguish them */
+	idp = mdesc_get_property(md, node, "id", NULL);
+	if (!idp)
+		return -1;
+
+	node_info->ds_port.id = *idp;
+
+	return 0;
+}
+
+static void rel_ds_port_node_info(union md_node_info *node_info)
+{
+}
+
+static bool ds_port_node_match(union md_node_info *a_node_info,
+			       union md_node_info *b_node_info)
+{
+	if (a_node_info->ds_port.id != b_node_info->ds_port.id)
+		return false;
+
+	return true;
+}
+
+/* Run 'func' on nodes which are in A but not in B.  */
+static void invoke_on_missing(const char *name,
+			      struct mdesc_handle *a,
+			      struct mdesc_handle *b,
+			      void (*func)(struct mdesc_handle *, u64,
+					   const char *node_name))
+{
+	mdesc_node_info_get_f get_info_func;
+	mdesc_node_info_rel_f rel_info_func;
+	mdesc_node_match_f node_match_func;
+	union md_node_info a_node_info;
+	union md_node_info b_node_info;
+	bool found;
+	u64 a_node;
+	u64 b_node;
+	int rv;
+
+	/*
+	 * Find the get_info, rel_info and node_match ops for the given
+	 * node name
+	 */
+	mdesc_get_node_ops(name, &get_info_func, &rel_info_func,
+			   &node_match_func);
+
+	/* If we didn't find a match, the node type is not supported */
+	if (!get_info_func || !rel_info_func || !node_match_func) {
+		pr_err("MD: %s node type is not supported\n", name);
+		return;
+	}
+
+	mdesc_for_each_node_by_name(a, a_node, name) {
+		found = false;
+
+		rv = get_info_func(a, a_node, &a_node_info);
+		if (rv != 0) {
+			pr_err("MD: Cannot find 1 or more required match properties for %s node.\n",
+			       name);
+			continue;
+		}
+
+		/* Check each node in B for node matching a_node */
+		mdesc_for_each_node_by_name(b, b_node, name) {
+			rv = get_info_func(b, b_node, &b_node_info);
+			if (rv != 0)
+				continue;
+
+			if (node_match_func(&a_node_info, &b_node_info)) {
+				found = true;
+				rel_info_func(&b_node_info);
+				break;
+			}
+
+			rel_info_func(&b_node_info);
+		}
+
+		rel_info_func(&a_node_info);
+
+		if (!found)
+			func(a, a_node, name);
+	}
+}
+
+static void notify_one(struct mdesc_notifier_client *p,
+		       struct mdesc_handle *old_hp,
+		       struct mdesc_handle *new_hp)
+{
+	invoke_on_missing(p->node_name, old_hp, new_hp, p->remove);
+	invoke_on_missing(p->node_name, new_hp, old_hp, p->add);
+}
+
+static void mdesc_notify_clients(struct mdesc_handle *old_hp,
+				 struct mdesc_handle *new_hp)
+{
+	struct mdesc_notifier_client *p = client_list;
+
+	while (p) {
+		notify_one(p, old_hp, new_hp);
+		p = p->next;
+	}
+}
+
+void mdesc_update(void)
+{
+	unsigned long len, real_len, status;
+	struct mdesc_handle *hp, *orig_hp;
+	unsigned long flags;
+
+	mutex_lock(&mdesc_mutex);
+
+	(void) sun4v_mach_desc(0UL, 0UL, &len);
+
+	hp = mdesc_alloc(len, &kmalloc_mdesc_memops);
+	if (!hp) {
+		printk(KERN_ERR "MD: mdesc alloc fails\n");
+		goto out;
+	}
+
+	status = sun4v_mach_desc(__pa(&hp->mdesc), len, &real_len);
+	if (status != HV_EOK || real_len > len) {
+		printk(KERN_ERR "MD: mdesc reread fails with %lu\n",
+		       status);
+		refcount_dec(&hp->refcnt);
+		mdesc_free(hp);
+		goto out;
+	}
+
+	spin_lock_irqsave(&mdesc_lock, flags);
+	orig_hp = cur_mdesc;
+	cur_mdesc = hp;
+	spin_unlock_irqrestore(&mdesc_lock, flags);
+
+	mdesc_notify_clients(orig_hp, hp);
+
+	spin_lock_irqsave(&mdesc_lock, flags);
+	if (refcount_dec_and_test(&orig_hp->refcnt))
+		mdesc_free(orig_hp);
+	else
+		list_add(&orig_hp->list, &mdesc_zombie_list);
+	spin_unlock_irqrestore(&mdesc_lock, flags);
+
+out:
+	mutex_unlock(&mdesc_mutex);
+}
+
+u64 mdesc_get_node(struct mdesc_handle *hp, const char *node_name,
+		   union md_node_info *node_info)
+{
+	mdesc_node_info_get_f get_info_func;
+	mdesc_node_info_rel_f rel_info_func;
+	mdesc_node_match_f node_match_func;
+	union md_node_info hp_node_info;
+	u64 hp_node;
+	int rv;
+
+	if (hp == NULL || node_name == NULL || node_info == NULL)
+		return MDESC_NODE_NULL;
+
+	/* Find the ops for the given node name */
+	mdesc_get_node_ops(node_name, &get_info_func, &rel_info_func,
+			   &node_match_func);
+
+	/* If we didn't find ops for the given node name, it is not supported */
+	if (!get_info_func || !rel_info_func || !node_match_func) {
+		pr_err("MD: %s node is not supported\n", node_name);
+		return -EINVAL;
+	}
+
+	mdesc_for_each_node_by_name(hp, hp_node, node_name) {
+		rv = get_info_func(hp, hp_node, &hp_node_info);
+		if (rv != 0)
+			continue;
+
+		if (node_match_func(node_info, &hp_node_info))
+			break;
+
+		rel_info_func(&hp_node_info);
+	}
+
+	rel_info_func(&hp_node_info);
+
+	return hp_node;
+}
+EXPORT_SYMBOL(mdesc_get_node);
+
+int mdesc_get_node_info(struct mdesc_handle *hp, u64 node,
+			const char *node_name, union md_node_info *node_info)
+{
+	mdesc_node_info_get_f get_info_func;
+	int rv;
+
+	if (hp == NULL || node == MDESC_NODE_NULL ||
+	    node_name == NULL || node_info == NULL)
+		return -EINVAL;
+
+	/* Find the get_info op for the given node name */
+	mdesc_get_node_ops(node_name, &get_info_func, NULL, NULL);
+
+	/* If we didn't find a get_info_func, the node name is not supported */
+	if (get_info_func == NULL) {
+		pr_err("MD: %s node is not supported\n", node_name);
+		return -EINVAL;
+	}
+
+	rv = get_info_func(hp, node, node_info);
+	if (rv != 0) {
+		pr_err("MD: Cannot find 1 or more required match properties for %s node.\n",
+		       node_name);
+		return -1;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(mdesc_get_node_info);
+
+static struct mdesc_elem *node_block(struct mdesc_hdr *mdesc)
+{
+	return (struct mdesc_elem *) mdesc->data;
+}
+
+static void *name_block(struct mdesc_hdr *mdesc)
+{
+	return ((void *) node_block(mdesc)) + mdesc->node_sz;
+}
+
+static void *data_block(struct mdesc_hdr *mdesc)
+{
+	return ((void *) name_block(mdesc)) + mdesc->name_sz;
+}
+
+u64 mdesc_node_by_name(struct mdesc_handle *hp,
+		       u64 from_node, const char *name)
+{
+	struct mdesc_elem *ep = node_block(&hp->mdesc);
+	const char *names = name_block(&hp->mdesc);
+	u64 last_node = hp->mdesc.node_sz / 16;
+	u64 ret;
+
+	if (from_node == MDESC_NODE_NULL) {
+		ret = from_node = 0;
+	} else if (from_node >= last_node) {
+		return MDESC_NODE_NULL;
+	} else {
+		ret = ep[from_node].d.val;
+	}
+
+	while (ret < last_node) {
+		if (ep[ret].tag != MD_NODE)
+			return MDESC_NODE_NULL;
+		if (!strcmp(names + ep[ret].name_offset, name))
+			break;
+		ret = ep[ret].d.val;
+	}
+	if (ret >= last_node)
+		ret = MDESC_NODE_NULL;
+	return ret;
+}
+EXPORT_SYMBOL(mdesc_node_by_name);
+
+const void *mdesc_get_property(struct mdesc_handle *hp, u64 node,
+			       const char *name, int *lenp)
+{
+	const char *names = name_block(&hp->mdesc);
+	u64 last_node = hp->mdesc.node_sz / 16;
+	void *data = data_block(&hp->mdesc);
+	struct mdesc_elem *ep;
+
+	if (node == MDESC_NODE_NULL || node >= last_node)
+		return NULL;
+
+	ep = node_block(&hp->mdesc) + node;
+	ep++;
+	for (; ep->tag != MD_NODE_END; ep++) {
+		void *val = NULL;
+		int len = 0;
+
+		switch (ep->tag) {
+		case MD_PROP_VAL:
+			val = &ep->d.val;
+			len = 8;
+			break;
+
+		case MD_PROP_STR:
+		case MD_PROP_DATA:
+			val = data + ep->d.data.data_offset;
+			len = ep->d.data.data_len;
+			break;
+
+		default:
+			break;
+		}
+		if (!val)
+			continue;
+
+		if (!strcmp(names + ep->name_offset, name)) {
+			if (lenp)
+				*lenp = len;
+			return val;
+		}
+	}
+
+	return NULL;
+}
+EXPORT_SYMBOL(mdesc_get_property);
+
+u64 mdesc_next_arc(struct mdesc_handle *hp, u64 from, const char *arc_type)
+{
+	struct mdesc_elem *ep, *base = node_block(&hp->mdesc);
+	const char *names = name_block(&hp->mdesc);
+	u64 last_node = hp->mdesc.node_sz / 16;
+
+	if (from == MDESC_NODE_NULL || from >= last_node)
+		return MDESC_NODE_NULL;
+
+	ep = base + from;
+
+	ep++;
+	for (; ep->tag != MD_NODE_END; ep++) {
+		if (ep->tag != MD_PROP_ARC)
+			continue;
+
+		if (strcmp(names + ep->name_offset, arc_type))
+			continue;
+
+		return ep - base;
+	}
+
+	return MDESC_NODE_NULL;
+}
+EXPORT_SYMBOL(mdesc_next_arc);
+
+u64 mdesc_arc_target(struct mdesc_handle *hp, u64 arc)
+{
+	struct mdesc_elem *ep, *base = node_block(&hp->mdesc);
+
+	ep = base + arc;
+
+	return ep->d.val;
+}
+EXPORT_SYMBOL(mdesc_arc_target);
+
+const char *mdesc_node_name(struct mdesc_handle *hp, u64 node)
+{
+	struct mdesc_elem *ep, *base = node_block(&hp->mdesc);
+	const char *names = name_block(&hp->mdesc);
+	u64 last_node = hp->mdesc.node_sz / 16;
+
+	if (node == MDESC_NODE_NULL || node >= last_node)
+		return NULL;
+
+	ep = base + node;
+	if (ep->tag != MD_NODE)
+		return NULL;
+
+	return names + ep->name_offset;
+}
+EXPORT_SYMBOL(mdesc_node_name);
+
+static u64 max_cpus = 64;
+
+static void __init report_platform_properties(void)
+{
+	struct mdesc_handle *hp = mdesc_grab();
+	u64 pn = mdesc_node_by_name(hp, MDESC_NODE_NULL, "platform");
+	const char *s;
+	const u64 *v;
+
+	if (pn == MDESC_NODE_NULL) {
+		prom_printf("No platform node in machine-description.\n");
+		prom_halt();
+	}
+
+	s = mdesc_get_property(hp, pn, "banner-name", NULL);
+	printk("PLATFORM: banner-name [%s]\n", s);
+	s = mdesc_get_property(hp, pn, "name", NULL);
+	printk("PLATFORM: name [%s]\n", s);
+
+	v = mdesc_get_property(hp, pn, "hostid", NULL);
+	if (v)
+		printk("PLATFORM: hostid [%08llx]\n", *v);
+	v = mdesc_get_property(hp, pn, "serial#", NULL);
+	if (v)
+		printk("PLATFORM: serial# [%08llx]\n", *v);
+	v = mdesc_get_property(hp, pn, "stick-frequency", NULL);
+	printk("PLATFORM: stick-frequency [%08llx]\n", *v);
+	v = mdesc_get_property(hp, pn, "mac-address", NULL);
+	if (v)
+		printk("PLATFORM: mac-address [%llx]\n", *v);
+	v = mdesc_get_property(hp, pn, "watchdog-resolution", NULL);
+	if (v)
+		printk("PLATFORM: watchdog-resolution [%llu ms]\n", *v);
+	v = mdesc_get_property(hp, pn, "watchdog-max-timeout", NULL);
+	if (v)
+		printk("PLATFORM: watchdog-max-timeout [%llu ms]\n", *v);
+	v = mdesc_get_property(hp, pn, "max-cpus", NULL);
+	if (v) {
+		max_cpus = *v;
+		printk("PLATFORM: max-cpus [%llu]\n", max_cpus);
+	}
+
+#ifdef CONFIG_SMP
+	{
+		int max_cpu, i;
+
+		if (v) {
+			max_cpu = *v;
+			if (max_cpu > NR_CPUS)
+				max_cpu = NR_CPUS;
+		} else {
+			max_cpu = NR_CPUS;
+		}
+		for (i = 0; i < max_cpu; i++)
+			set_cpu_possible(i, true);
+	}
+#endif
+
+	mdesc_release(hp);
+}
+
+static void fill_in_one_cache(cpuinfo_sparc *c, struct mdesc_handle *hp, u64 mp)
+{
+	const u64 *level = mdesc_get_property(hp, mp, "level", NULL);
+	const u64 *size = mdesc_get_property(hp, mp, "size", NULL);
+	const u64 *line_size = mdesc_get_property(hp, mp, "line-size", NULL);
+	const char *type;
+	int type_len;
+
+	type = mdesc_get_property(hp, mp, "type", &type_len);
+
+	switch (*level) {
+	case 1:
+		if (of_find_in_proplist(type, "instn", type_len)) {
+			c->icache_size = *size;
+			c->icache_line_size = *line_size;
+		} else if (of_find_in_proplist(type, "data", type_len)) {
+			c->dcache_size = *size;
+			c->dcache_line_size = *line_size;
+		}
+		break;
+
+	case 2:
+		c->ecache_size = *size;
+		c->ecache_line_size = *line_size;
+		break;
+
+	default:
+		break;
+	}
+
+	if (*level == 1) {
+		u64 a;
+
+		mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_FWD) {
+			u64 target = mdesc_arc_target(hp, a);
+			const char *name = mdesc_node_name(hp, target);
+
+			if (!strcmp(name, "cache"))
+				fill_in_one_cache(c, hp, target);
+		}
+	}
+}
+
+static void find_back_node_value(struct mdesc_handle *hp, u64 node,
+				 char *srch_val,
+				 void (*func)(struct mdesc_handle *, u64, int),
+				 u64 val, int depth)
+{
+	u64 arc;
+
+	/* Since we have an estimate of recursion depth, do a sanity check. */
+	if (depth == 0)
+		return;
+
+	mdesc_for_each_arc(arc, hp, node, MDESC_ARC_TYPE_BACK) {
+		u64 n = mdesc_arc_target(hp, arc);
+		const char *name = mdesc_node_name(hp, n);
+
+		if (!strcmp(srch_val, name))
+			(*func)(hp, n, val);
+
+		find_back_node_value(hp, n, srch_val, func, val, depth-1);
+	}
+}
+
+static void __mark_core_id(struct mdesc_handle *hp, u64 node,
+			   int core_id)
+{
+	const u64 *id = mdesc_get_property(hp, node, "id", NULL);
+
+	if (*id < num_possible_cpus())
+		cpu_data(*id).core_id = core_id;
+}
+
+static void __mark_max_cache_id(struct mdesc_handle *hp, u64 node,
+				int max_cache_id)
+{
+	const u64 *id = mdesc_get_property(hp, node, "id", NULL);
+
+	if (*id < num_possible_cpus()) {
+		cpu_data(*id).max_cache_id = max_cache_id;
+
+		/**
+		 * On systems without explicit socket descriptions socket
+		 * is max_cache_id
+		 */
+		cpu_data(*id).sock_id = max_cache_id;
+	}
+}
+
+static void mark_core_ids(struct mdesc_handle *hp, u64 mp,
+			  int core_id)
+{
+	find_back_node_value(hp, mp, "cpu", __mark_core_id, core_id, 10);
+}
+
+static void mark_max_cache_ids(struct mdesc_handle *hp, u64 mp,
+			       int max_cache_id)
+{
+	find_back_node_value(hp, mp, "cpu", __mark_max_cache_id,
+			     max_cache_id, 10);
+}
+
+static void set_core_ids(struct mdesc_handle *hp)
+{
+	int idx;
+	u64 mp;
+
+	idx = 1;
+
+	/* Identify unique cores by looking for cpus backpointed to by
+	 * level 1 instruction caches.
+	 */
+	mdesc_for_each_node_by_name(hp, mp, "cache") {
+		const u64 *level;
+		const char *type;
+		int len;
+
+		level = mdesc_get_property(hp, mp, "level", NULL);
+		if (*level != 1)
+			continue;
+
+		type = mdesc_get_property(hp, mp, "type", &len);
+		if (!of_find_in_proplist(type, "instn", len))
+			continue;
+
+		mark_core_ids(hp, mp, idx);
+		idx++;
+	}
+}
+
+static int set_max_cache_ids_by_cache(struct mdesc_handle *hp, int level)
+{
+	u64 mp;
+	int idx = 1;
+	int fnd = 0;
+
+	/**
+	 * Identify unique highest level of shared cache by looking for cpus
+	 * backpointed to by shared level N caches.
+	 */
+	mdesc_for_each_node_by_name(hp, mp, "cache") {
+		const u64 *cur_lvl;
+
+		cur_lvl = mdesc_get_property(hp, mp, "level", NULL);
+		if (*cur_lvl != level)
+			continue;
+		mark_max_cache_ids(hp, mp, idx);
+		idx++;
+		fnd = 1;
+	}
+	return fnd;
+}
+
+static void set_sock_ids_by_socket(struct mdesc_handle *hp, u64 mp)
+{
+	int idx = 1;
+
+	mdesc_for_each_node_by_name(hp, mp, "socket") {
+		u64 a;
+
+		mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_FWD) {
+			u64 t = mdesc_arc_target(hp, a);
+			const char *name;
+			const u64 *id;
+
+			name = mdesc_node_name(hp, t);
+			if (strcmp(name, "cpu"))
+				continue;
+
+			id = mdesc_get_property(hp, t, "id", NULL);
+			if (*id < num_possible_cpus())
+				cpu_data(*id).sock_id = idx;
+		}
+		idx++;
+	}
+}
+
+static void set_sock_ids(struct mdesc_handle *hp)
+{
+	u64 mp;
+
+	/**
+	 * Find the highest level of shared cache which pre-T7 is also
+	 * the socket.
+	 */
+	if (!set_max_cache_ids_by_cache(hp, 3))
+		set_max_cache_ids_by_cache(hp, 2);
+
+	/* If machine description exposes sockets data use it.*/
+	mp = mdesc_node_by_name(hp, MDESC_NODE_NULL, "sockets");
+	if (mp != MDESC_NODE_NULL)
+		set_sock_ids_by_socket(hp, mp);
+}
+
+static void mark_proc_ids(struct mdesc_handle *hp, u64 mp, int proc_id)
+{
+	u64 a;
+
+	mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_BACK) {
+		u64 t = mdesc_arc_target(hp, a);
+		const char *name;
+		const u64 *id;
+
+		name = mdesc_node_name(hp, t);
+		if (strcmp(name, "cpu"))
+			continue;
+
+		id = mdesc_get_property(hp, t, "id", NULL);
+		if (*id < NR_CPUS)
+			cpu_data(*id).proc_id = proc_id;
+	}
+}
+
+static void __set_proc_ids(struct mdesc_handle *hp, const char *exec_unit_name)
+{
+	int idx;
+	u64 mp;
+
+	idx = 0;
+	mdesc_for_each_node_by_name(hp, mp, exec_unit_name) {
+		const char *type;
+		int len;
+
+		type = mdesc_get_property(hp, mp, "type", &len);
+		if (!of_find_in_proplist(type, "int", len) &&
+		    !of_find_in_proplist(type, "integer", len))
+			continue;
+
+		mark_proc_ids(hp, mp, idx);
+		idx++;
+	}
+}
+
+static void set_proc_ids(struct mdesc_handle *hp)
+{
+	__set_proc_ids(hp, "exec_unit");
+	__set_proc_ids(hp, "exec-unit");
+}
+
+static void get_one_mondo_bits(const u64 *p, unsigned int *mask,
+			       unsigned long def, unsigned long max)
+{
+	u64 val;
+
+	if (!p)
+		goto use_default;
+	val = *p;
+
+	if (!val || val >= 64)
+		goto use_default;
+
+	if (val > max)
+		val = max;
+
+	*mask = ((1U << val) * 64U) - 1U;
+	return;
+
+use_default:
+	*mask = ((1U << def) * 64U) - 1U;
+}
+
+static void get_mondo_data(struct mdesc_handle *hp, u64 mp,
+			   struct trap_per_cpu *tb)
+{
+	static int printed;
+	const u64 *val;
+
+	val = mdesc_get_property(hp, mp, "q-cpu-mondo-#bits", NULL);
+	get_one_mondo_bits(val, &tb->cpu_mondo_qmask, 7, ilog2(max_cpus * 2));
+
+	val = mdesc_get_property(hp, mp, "q-dev-mondo-#bits", NULL);
+	get_one_mondo_bits(val, &tb->dev_mondo_qmask, 7, 8);
+
+	val = mdesc_get_property(hp, mp, "q-resumable-#bits", NULL);
+	get_one_mondo_bits(val, &tb->resum_qmask, 6, 7);
+
+	val = mdesc_get_property(hp, mp, "q-nonresumable-#bits", NULL);
+	get_one_mondo_bits(val, &tb->nonresum_qmask, 2, 2);
+	if (!printed++) {
+		pr_info("SUN4V: Mondo queue sizes "
+			"[cpu(%u) dev(%u) r(%u) nr(%u)]\n",
+			tb->cpu_mondo_qmask + 1,
+			tb->dev_mondo_qmask + 1,
+			tb->resum_qmask + 1,
+			tb->nonresum_qmask + 1);
+	}
+}
+
+static void *mdesc_iterate_over_cpus(void *(*func)(struct mdesc_handle *, u64, int, void *), void *arg, cpumask_t *mask)
+{
+	struct mdesc_handle *hp = mdesc_grab();
+	void *ret = NULL;
+	u64 mp;
+
+	mdesc_for_each_node_by_name(hp, mp, "cpu") {
+		const u64 *id = mdesc_get_property(hp, mp, "id", NULL);
+		int cpuid = *id;
+
+#ifdef CONFIG_SMP
+		if (cpuid >= NR_CPUS) {
+			printk(KERN_WARNING "Ignoring CPU %d which is "
+			       ">= NR_CPUS (%d)\n",
+			       cpuid, NR_CPUS);
+			continue;
+		}
+		if (!cpumask_test_cpu(cpuid, mask))
+			continue;
+#endif
+
+		ret = func(hp, mp, cpuid, arg);
+		if (ret)
+			goto out;
+	}
+out:
+	mdesc_release(hp);
+	return ret;
+}
+
+static void *record_one_cpu(struct mdesc_handle *hp, u64 mp, int cpuid,
+			    void *arg)
+{
+	ncpus_probed++;
+#ifdef CONFIG_SMP
+	set_cpu_present(cpuid, true);
+#endif
+	return NULL;
+}
+
+void mdesc_populate_present_mask(cpumask_t *mask)
+{
+	if (tlb_type != hypervisor)
+		return;
+
+	ncpus_probed = 0;
+	mdesc_iterate_over_cpus(record_one_cpu, NULL, mask);
+}
+
+static void * __init check_one_pgsz(struct mdesc_handle *hp, u64 mp, int cpuid, void *arg)
+{
+	const u64 *pgsz_prop = mdesc_get_property(hp, mp, "mmu-page-size-list", NULL);
+	unsigned long *pgsz_mask = arg;
+	u64 val;
+
+	val = (HV_PGSZ_MASK_8K | HV_PGSZ_MASK_64K |
+	       HV_PGSZ_MASK_512K | HV_PGSZ_MASK_4MB);
+	if (pgsz_prop)
+		val = *pgsz_prop;
+
+	if (!*pgsz_mask)
+		*pgsz_mask = val;
+	else
+		*pgsz_mask &= val;
+	return NULL;
+}
+
+void __init mdesc_get_page_sizes(cpumask_t *mask, unsigned long *pgsz_mask)
+{
+	*pgsz_mask = 0;
+	mdesc_iterate_over_cpus(check_one_pgsz, pgsz_mask, mask);
+}
+
+static void *fill_in_one_cpu(struct mdesc_handle *hp, u64 mp, int cpuid,
+			     void *arg)
+{
+	const u64 *cfreq = mdesc_get_property(hp, mp, "clock-frequency", NULL);
+	struct trap_per_cpu *tb;
+	cpuinfo_sparc *c;
+	u64 a;
+
+#ifndef CONFIG_SMP
+	/* On uniprocessor we only want the values for the
+	 * real physical cpu the kernel booted onto, however
+	 * cpu_data() only has one entry at index 0.
+	 */
+	if (cpuid != real_hard_smp_processor_id())
+		return NULL;
+	cpuid = 0;
+#endif
+
+	c = &cpu_data(cpuid);
+	c->clock_tick = *cfreq;
+
+	tb = &trap_block[cpuid];
+	get_mondo_data(hp, mp, tb);
+
+	mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_FWD) {
+		u64 j, t = mdesc_arc_target(hp, a);
+		const char *t_name;
+
+		t_name = mdesc_node_name(hp, t);
+		if (!strcmp(t_name, "cache")) {
+			fill_in_one_cache(c, hp, t);
+			continue;
+		}
+
+		mdesc_for_each_arc(j, hp, t, MDESC_ARC_TYPE_FWD) {
+			u64 n = mdesc_arc_target(hp, j);
+			const char *n_name;
+
+			n_name = mdesc_node_name(hp, n);
+			if (!strcmp(n_name, "cache"))
+				fill_in_one_cache(c, hp, n);
+		}
+	}
+
+	c->core_id = 0;
+	c->proc_id = -1;
+
+	return NULL;
+}
+
+void mdesc_fill_in_cpu_data(cpumask_t *mask)
+{
+	struct mdesc_handle *hp;
+
+	mdesc_iterate_over_cpus(fill_in_one_cpu, NULL, mask);
+
+	hp = mdesc_grab();
+
+	set_core_ids(hp);
+	set_proc_ids(hp);
+	set_sock_ids(hp);
+
+	mdesc_release(hp);
+
+	smp_fill_in_sib_core_maps();
+}
+
+/* mdesc_open() - Grab a reference to mdesc_handle when /dev/mdesc is
+ * opened. Hold this reference until /dev/mdesc is closed to ensure
+ * mdesc data structure is not released underneath us. Store the
+ * pointer to mdesc structure in private_data for read and seek to use
+ */
+static int mdesc_open(struct inode *inode, struct file *file)
+{
+	struct mdesc_handle *hp = mdesc_grab();
+
+	if (!hp)
+		return -ENODEV;
+
+	file->private_data = hp;
+
+	return 0;
+}
+
+static ssize_t mdesc_read(struct file *file, char __user *buf,
+			  size_t len, loff_t *offp)
+{
+	struct mdesc_handle *hp = file->private_data;
+	unsigned char *mdesc;
+	int bytes_left, count = len;
+
+	if (*offp >= hp->handle_size)
+		return 0;
+
+	bytes_left = hp->handle_size - *offp;
+	if (count > bytes_left)
+		count = bytes_left;
+
+	mdesc = (unsigned char *)&hp->mdesc;
+	mdesc += *offp;
+	if (!copy_to_user(buf, mdesc, count)) {
+		*offp += count;
+		return count;
+	} else {
+		return -EFAULT;
+	}
+}
+
+static loff_t mdesc_llseek(struct file *file, loff_t offset, int whence)
+{
+	struct mdesc_handle *hp = file->private_data;
+
+	return no_seek_end_llseek_size(file, offset, whence, hp->handle_size);
+}
+
+/* mdesc_close() - /dev/mdesc is being closed, release the reference to
+ * mdesc structure.
+ */
+static int mdesc_close(struct inode *inode, struct file *file)
+{
+	mdesc_release(file->private_data);
+	return 0;
+}
+
+static const struct file_operations mdesc_fops = {
+	.open    = mdesc_open,
+	.read	 = mdesc_read,
+	.llseek  = mdesc_llseek,
+	.release = mdesc_close,
+	.owner	 = THIS_MODULE,
+};
+
+static struct miscdevice mdesc_misc = {
+	.minor	= MISC_DYNAMIC_MINOR,
+	.name	= "mdesc",
+	.fops	= &mdesc_fops,
+};
+
+static int __init mdesc_misc_init(void)
+{
+	return misc_register(&mdesc_misc);
+}
+
+__initcall(mdesc_misc_init);
+
+void __init sun4v_mdesc_init(void)
+{
+	struct mdesc_handle *hp;
+	unsigned long len, real_len, status;
+
+	(void) sun4v_mach_desc(0UL, 0UL, &len);
+
+	printk("MDESC: Size is %lu bytes.\n", len);
+
+	hp = mdesc_alloc(len, &memblock_mdesc_ops);
+	if (hp == NULL) {
+		prom_printf("MDESC: alloc of %lu bytes failed.\n", len);
+		prom_halt();
+	}
+
+	status = sun4v_mach_desc(__pa(&hp->mdesc), len, &real_len);
+	if (status != HV_EOK || real_len > len) {
+		prom_printf("sun4v_mach_desc fails, err(%lu), "
+			    "len(%lu), real_len(%lu)\n",
+			    status, len, real_len);
+		mdesc_free(hp);
+		prom_halt();
+	}
+
+	cur_mdesc = hp;
+
+	mdesc_adi_init();
+	report_platform_properties();
+}