Merge branch 'sparc64-add-MDESC-and-VIO-support-for-VCC'

Jag Raman says:

====================
sparc64: Add MDESC & VIO support for VCC

This series of patches is part of an effort to add VCC (Virtual Console
Concentrator) support to Linux.

VCC enables the virtualization of serial console on SPARC processors. VCC
provides access to the guest domain's serial console.

VCC depends on some core functionalities in the linux kernel for SPARC. The
functionalities include LDC (Logical Domain Channels), MDESC (Machine
Descriptor) and VIO (Virtual IO protocol). In order for VCC to be enabled,
it requires that these core functionalities support them.

This series of patches adds MDESC & VIO support to enable VCC on Linux. It
is the second batch of changes to enable VCC.

This version of the series addresses the following changes
suggested by Dave Miller
Patch 4/5:
 - "name" field in vdev_port md_node_info is declared as "const char *"
 - Code has been modified to dynamically allocate & free "name" in
   vdev_port md_node_info
 - Parameters to mdesc_get_node(), mdesc_get_node_info() &
   mdesc_get_node_ops() have been updated to use "const char *"

Patch 6/5:
 - "node_name" parameter in vio_create_one() has been
   changed to "const char *" type from "char *"
 - Typecasts in vio_create_one() invocations to convert
   "const char *" to "char *" have been removed

Patch 11/5:
 - Invocations of mdesc_node_get() & mdesc_get_node_info()
   have been updated to use the prototypes defined in patch 4/5
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc/include/asm/mdesc.h

@@ -16,6 +16,7 @@ struct mdesc_handle *mdesc_grab(void);
 void mdesc_release(struct mdesc_handle *);
 
 #define MDESC_NODE_NULL		(~(u64)0)
+#define MDESC_MAX_STR_LEN	256
 
 u64 mdesc_node_by_name(struct mdesc_handle *handle,
 		       u64 from_node, const char *name);
@@ -62,15 +63,32 @@ u64 mdesc_arc_target(struct mdesc_handle *hp, u64 arc);
 void mdesc_update(void);
 
 struct mdesc_notifier_client {
-	void (*add)(struct mdesc_handle *handle, u64 node);
-	void (*remove)(struct mdesc_handle *handle, u64 node);
-
+	void (*add)(struct mdesc_handle *handle, u64 node,
+		    const char *node_name);
+	void (*remove)(struct mdesc_handle *handle, u64 node,
+		       const char *node_name);
 	const char			*node_name;
 	struct mdesc_notifier_client	*next;
 };
 
 void mdesc_register_notifier(struct mdesc_notifier_client *client);
 
+union md_node_info {
+	struct vdev_port {
+		u64 id;				/* id */
+		u64 parent_cfg_hdl;		/* parent config handle */
+		const char *name;		/* name (property) */
+	} vdev_port;
+	struct ds_port {
+		u64 id;				/* id */
+	} ds_port;
+};
+
+u64 mdesc_get_node(struct mdesc_handle *hp, const char *node_name,
+		   union md_node_info *node_info);
+int mdesc_get_node_info(struct mdesc_handle *hp, u64 node,
+			const char *node_name, union md_node_info *node_info);
+
 void mdesc_fill_in_cpu_data(cpumask_t *mask);
 void mdesc_populate_present_mask(cpumask_t *mask);
 void mdesc_get_page_sizes(cpumask_t *mask, unsigned long *pgsz_mask);

arch/sparc/include/asm/vio.h

@@ -316,24 +316,33 @@ static inline u32 vio_dring_prev(struct vio_dring_state *dr, u32 index)
 }
 
 #define VIO_MAX_TYPE_LEN	32
+#define VIO_MAX_NAME_LEN	32
 #define VIO_MAX_COMPAT_LEN	64
 
 struct vio_dev {
 	u64			mp;
 	struct device_node	*dp;
 
+	char			node_name[VIO_MAX_NAME_LEN];
 	char			type[VIO_MAX_TYPE_LEN];
 	char			compat[VIO_MAX_COMPAT_LEN];
 	int			compat_len;
 
 	u64			dev_no;
-	u64			id;
 
+	unsigned long		port_id;
 	unsigned long		channel_id;
 
 	unsigned int		tx_irq;
 	unsigned int		rx_irq;
 	u64			rx_ino;
+	u64			tx_ino;
+
+	/* Handle to the root of "channel-devices" sub-tree in MDESC */
+	u64			cdev_handle;
+
+	/* MD specific data used to identify the vdev in MD */
+	union md_node_info	md_node_info;
 
 	struct device		dev;
 };
@@ -347,6 +356,7 @@ struct vio_driver {
 	void (*shutdown)(struct vio_dev *dev);
 	unsigned long			driver_data;
 	struct device_driver		driver;
+	bool				no_irq;
 };
 
 struct vio_version {
@@ -490,5 +500,6 @@ int vio_driver_init(struct vio_driver_state *vio, struct vio_dev *vdev,
 
 void vio_port_up(struct vio_driver_state *vio);
 int vio_set_intr(unsigned long dev_ino, int state);
+u64 vio_vdev_node(struct mdesc_handle *hp, struct vio_dev *vdev);
 
 #endif /* _SPARC64_VIO_H */

arch/sparc/kernel/ldc.c

@@ -1347,6 +1347,14 @@ int ldc_bind(struct ldc_channel *lp)
 	lp->hs_state = LDC_HS_OPEN;
 	ldc_set_state(lp, LDC_STATE_BOUND);
 
+	if (lp->cfg.mode == LDC_MODE_RAW) {
+		/*
+		 * There is no handshake in RAW mode, so handshake
+		 * is completed.
+		 */
+		lp->hs_state = LDC_HS_COMPLETE;
+	}
+
 	spin_unlock_irqrestore(&lp->lock, flags);
 
 	return 0;
@@ -1460,11 +1468,13 @@ void ldc_set_state(struct ldc_channel *lp, u8 state)
 
 	lp->state = state;
 }
+EXPORT_SYMBOL(ldc_set_state);
 
 int ldc_mode(struct ldc_channel *lp)
 {
 	return lp->cfg.mode;
 }
+EXPORT_SYMBOL(ldc_mode);
 
 int ldc_rx_reset(struct ldc_channel *lp)
 {

arch/sparc/kernel/mdesc.c

@@ -75,6 +75,74 @@ struct mdesc_handle {
 	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)
@@ -137,12 +205,10 @@ static struct mdesc_handle *mdesc_kmalloc(unsigned int mdesc_size)
 	handle_size = (sizeof(struct mdesc_handle) -
 		       sizeof(struct mdesc_hdr) +
 		       mdesc_size);
+	base = kmalloc(handle_size + 15, GFP_KERNEL | __GFP_REPEAT);
+	if (!base)
+		return NULL;
 
-	/*
-	 * Allocation has to succeed because mdesc update would be missed
-	 * and such events are not retransmitted.
-	 */
-	base = kmalloc(handle_size + 15, GFP_KERNEL | __GFP_NOFAIL);
 	addr = (unsigned long)base;
 	addr = (addr + 15UL) & ~15UL;
 	hp = (struct mdesc_handle *) addr;
@@ -218,14 +284,31 @@ 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->add(cur_mdesc, node, client->node_name);
 
 	mutex_unlock(&mdesc_mutex);
 }
@@ -249,59 +332,145 @@ static const u64 *parent_cfg_handle(struct mdesc_handle *hp, u64 node)
 	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);
+	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))
+			      void (*func)(struct mdesc_handle *, u64,
+					   const char *node_name))
 {
-	u64 node;
+	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;
 
-	mdesc_for_each_node_by_name(a, node, name) {
-		int found = 0, is_vdc_port = 0;
-		const char *name_prop;
-		const u64 *id;
-		u64 fnode;
-
-		name_prop = mdesc_get_property(a, node, "name", NULL);
-		if (name_prop && !strcmp(name_prop, "vdc-port")) {
-			is_vdc_port = 1;
-			id = parent_cfg_handle(a, node);
-		} else
-			id = mdesc_get_property(a, node, "id", NULL);
-
-		if (!id) {
-			printk(KERN_ERR "MD: Cannot find ID for %s node.\n",
-			       (name_prop ? name_prop : name));
-			continue;
+	/*
+	 * 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(b, fnode, name) {
-			const u64 *fid;
+	mdesc_for_each_node_by_name(a, a_node, name) {
+		found = false;
 
-			if (is_vdc_port) {
-				name_prop = mdesc_get_property(b, fnode,
-							       "name", NULL);
-				if (!name_prop ||
-				    strcmp(name_prop, "vdc-port"))
-					continue;
-				fid = parent_cfg_handle(b, fnode);
-				if (!fid) {
-					printk(KERN_ERR "MD: Cannot find ID "
-					       "for vdc-port node.\n");
+		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;
 		}
-			} else
-				fid = mdesc_get_property(b, fnode,
-							 "id", NULL);
 
-			if (*id == *fid) {
-				found = 1;
+		/* 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, node);
+			func(a, a_node, name);
 	}
 }
 
@@ -367,6 +536,76 @@ void mdesc_update(void)
 	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 + 1);

arch/sparc/kernel/vio.c

@@ -70,15 +70,26 @@ static int vio_device_probe(struct device *dev)
 	struct vio_dev *vdev = to_vio_dev(dev);
 	struct vio_driver *drv = to_vio_driver(dev->driver);
 	const struct vio_device_id *id;
-	int error = -ENODEV;
 
-	if (drv->probe) {
+	if (!drv->probe)
+		return -ENODEV;
+
 	id = vio_match_device(drv->id_table, vdev);
-		if (id)
-			error = drv->probe(vdev, id);
+	if (!id)
+		return -ENODEV;
+
+	/* alloc irqs (unless the driver specified not to) */
+	if (!drv->no_irq) {
+		if (vdev->tx_irq == 0 && vdev->tx_ino != ~0UL)
+			vdev->tx_irq = sun4v_build_virq(vdev->cdev_handle,
+							vdev->tx_ino);
+
+		if (vdev->rx_irq == 0 && vdev->rx_ino != ~0UL)
+			vdev->rx_irq = sun4v_build_virq(vdev->cdev_handle,
+							vdev->rx_ino);
 	}
 
-	return error;
+	return drv->probe(vdev, id);
 }
 
 static int vio_device_remove(struct device *dev)
@@ -86,8 +97,15 @@ static int vio_device_remove(struct device *dev)
 	struct vio_dev *vdev = to_vio_dev(dev);
 	struct vio_driver *drv = to_vio_driver(dev->driver);
 
-	if (drv->remove)
+	if (drv->remove) {
+		/*
+		 * Ideally, we would remove/deallocate tx/rx virqs
+		 * here - however, there are currently no support
+		 * routines to do so at the moment. TBD
+		 */
+
 		return drv->remove(vdev);
+	}
 
 	return 1;
 }
@@ -181,11 +199,58 @@ static struct device_node *cdev_node;
 static struct vio_dev *root_vdev;
 static u64 cdev_cfg_handle;
 
+static const u64 *vio_cfg_handle(struct mdesc_handle *hp, u64 node)
+{
+	const u64 *cfg_handle = NULL;
+	u64 a;
+
+	mdesc_for_each_arc(a, hp, node, MDESC_ARC_TYPE_BACK) {
+		u64 target;
+
+		target = mdesc_arc_target(hp, a);
+		cfg_handle = mdesc_get_property(hp, target,
+						"cfg-handle", NULL);
+		if (cfg_handle)
+			break;
+	}
+
+	return cfg_handle;
+}
+
+/**
+ * vio_vdev_node() - Find VDEV node in MD
+ * @hp:  Handle to the MD
+ * @vdev:  Pointer to VDEV
+ *
+ * Find the node in the current MD which matches the given vio_dev. This
+ * must be done dynamically since the node value can change if the MD
+ * is updated.
+ *
+ * NOTE: the MD must be locked, using mdesc_grab(), when calling this routine
+ *
+ * Return: The VDEV node in MDESC
+ */
+u64 vio_vdev_node(struct mdesc_handle *hp, struct vio_dev *vdev)
+{
+	u64 node;
+
+	if (vdev == NULL)
+		return MDESC_NODE_NULL;
+
+	node = mdesc_get_node(hp, (const char *)vdev->node_name,
+			      &vdev->md_node_info);
+
+	return node;
+}
+
 static void vio_fill_channel_info(struct mdesc_handle *hp, u64 mp,
 				  struct vio_dev *vdev)
 {
 	u64 a;
 
+	vdev->tx_ino = ~0UL;
+	vdev->rx_ino = ~0UL;
+	vdev->channel_id = ~0UL;
 	mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_FWD) {
 		const u64 *chan_id;
 		const u64 *irq;
@@ -195,18 +260,18 @@ static void vio_fill_channel_info(struct mdesc_handle *hp, u64 mp,
 
 		irq = mdesc_get_property(hp, target, "tx-ino", NULL);
 		if (irq)
-			vdev->tx_irq = sun4v_build_virq(cdev_cfg_handle, *irq);
+			vdev->tx_ino = *irq;
 
 		irq = mdesc_get_property(hp, target, "rx-ino", NULL);
-		if (irq) {
-			vdev->rx_irq = sun4v_build_virq(cdev_cfg_handle, *irq);
+		if (irq)
 			vdev->rx_ino = *irq;
-		}
 
 		chan_id = mdesc_get_property(hp, target, "id", NULL);
 		if (chan_id)
 			vdev->channel_id = *chan_id;
 	}
+
+	vdev->cdev_handle = cdev_cfg_handle;
 }
 
 int vio_set_intr(unsigned long dev_ino, int state)
@@ -219,14 +284,14 @@ int vio_set_intr(unsigned long dev_ino, int state)
 EXPORT_SYMBOL(vio_set_intr);
 
 static struct vio_dev *vio_create_one(struct mdesc_handle *hp, u64 mp,
+				      const char *node_name,
 				      struct device *parent)
 {
-	const char *type, *compat, *bus_id_name;
+	const char *type, *compat;
 	struct device_node *dp;
 	struct vio_dev *vdev;
 	int err, tlen, clen;
 	const u64 *id, *cfg_handle;
-	u64 a;
 
 	type = mdesc_get_property(hp, mp, "device-type", &tlen);
 	if (!type) {
@@ -236,7 +301,7 @@ static struct vio_dev *vio_create_one(struct mdesc_handle *hp, u64 mp,
 			tlen = strlen(type) + 1;
 		}
 	}
-	if (tlen > VIO_MAX_TYPE_LEN) {
+	if (tlen > VIO_MAX_TYPE_LEN || strlen(type) >= VIO_MAX_TYPE_LEN) {
 		printk(KERN_ERR "VIO: Type string [%s] is too long.\n",
 		       type);
 		return NULL;
@@ -244,31 +309,7 @@ static struct vio_dev *vio_create_one(struct mdesc_handle *hp, u64 mp,
 
 	id = mdesc_get_property(hp, mp, "id", NULL);
 
-	cfg_handle = NULL;
-	mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_BACK) {
-		u64 target;
-
-		target = mdesc_arc_target(hp, a);
-		cfg_handle = mdesc_get_property(hp, target,
-						"cfg-handle", NULL);
-		if (cfg_handle)
-			break;
-	}
-
-	bus_id_name = type;
-	if (!strcmp(type, "domain-services-port"))
-		bus_id_name = "ds";
-
-	/*
-	 * 20 char is the old driver-core name size limit, which is no more.
-	 * This check can probably be removed after review and possible
-	 * adaption of the vio users name length handling.
-	 */
-	if (strlen(bus_id_name) >= 20 - 4) {
-		printk(KERN_ERR "VIO: bus_id_name [%s] is too long.\n",
-		       bus_id_name);
-		return NULL;
-	}
+	cfg_handle = vio_cfg_handle(hp, mp);
 
 	compat = mdesc_get_property(hp, mp, "device-type", &clen);
 	if (!compat) {
@@ -293,25 +334,23 @@ static struct vio_dev *vio_create_one(struct mdesc_handle *hp, u64 mp,
 		memset(vdev->compat, 0, sizeof(vdev->compat));
 	vdev->compat_len = clen;
 
-	vdev->channel_id = ~0UL;
-	vdev->tx_irq = ~0;
-	vdev->rx_irq = ~0;
+	vdev->port_id = ~0UL;
+	vdev->tx_irq = 0;
+	vdev->rx_irq = 0;
 
 	vio_fill_channel_info(hp, mp, vdev);
 
 	if (!id) {
-		dev_set_name(&vdev->dev, "%s", bus_id_name);
+		dev_set_name(&vdev->dev, "%s", type);
 		vdev->dev_no = ~(u64)0;
-		vdev->id = ~(u64)0;
 	} else if (!cfg_handle) {
-		dev_set_name(&vdev->dev, "%s-%llu", bus_id_name, *id);
+		dev_set_name(&vdev->dev, "%s-%llu", type, *id);
 		vdev->dev_no = *id;
-		vdev->id = ~(u64)0;
 	} else {
-		dev_set_name(&vdev->dev, "%s-%llu-%llu", bus_id_name,
+		dev_set_name(&vdev->dev, "%s-%llu-%llu", type,
 			     *cfg_handle, *id);
 		vdev->dev_no = *cfg_handle;
-		vdev->id = *id;
+		vdev->port_id = *id;
 	}
 
 	vdev->dev.parent = parent;
@@ -333,7 +372,26 @@ static struct vio_dev *vio_create_one(struct mdesc_handle *hp, u64 mp,
 	}
 	vdev->dp = dp;
 
-	printk(KERN_INFO "VIO: Adding device %s\n", dev_name(&vdev->dev));
+	/*
+	 * node_name is NULL for the parent/channel-devices node and
+	 * the parent doesn't require the MD node info.
+	 */
+	if (node_name != NULL) {
+		(void) snprintf(vdev->node_name, VIO_MAX_NAME_LEN, "%s",
+				node_name);
+
+		err = mdesc_get_node_info(hp, mp, node_name,
+					  &vdev->md_node_info);
+		if (err) {
+			pr_err("VIO: Could not get MD node info %s, err=%d\n",
+			       dev_name(&vdev->dev), err);
+			kfree(vdev);
+			return NULL;
+		}
+	}
+
+	pr_info("VIO: Adding device %s (tx_ino = %llx, rx_ino = %llx)\n",
+		dev_name(&vdev->dev), vdev->tx_ino, vdev->rx_ino);
 
 	err = device_register(&vdev->dev);
 	if (err) {
@@ -349,73 +407,42 @@ static struct vio_dev *vio_create_one(struct mdesc_handle *hp, u64 mp,
 	return vdev;
 }
 
-static void vio_add(struct mdesc_handle *hp, u64 node)
+static void vio_add(struct mdesc_handle *hp, u64 node,
+		    const char *node_name)
 {
-	(void) vio_create_one(hp, node, &root_vdev->dev);
+	(void) vio_create_one(hp, node, node_name, &root_vdev->dev);
 }
 
-struct vio_md_node_query {
-	const char *type;
-	u64 dev_no;
-	u64 id;
+struct vio_remove_node_data {
+	struct mdesc_handle *hp;
+	u64 node;
 };
 
 static int vio_md_node_match(struct device *dev, void *arg)
 {
-	struct vio_md_node_query *query = (struct vio_md_node_query *) arg;
 	struct vio_dev *vdev = to_vio_dev(dev);
+	struct vio_remove_node_data *node_data;
+	u64 node;
 
-	if (vdev->dev_no != query->dev_no)
-		return 0;
-	if (vdev->id != query->id)
-		return 0;
-	if (strcmp(vdev->type, query->type))
-		return 0;
+	node_data = (struct vio_remove_node_data *)arg;
 
+	node = vio_vdev_node(node_data->hp, vdev);
+
+	if (node == node_data->node)
 		return 1;
+	else
+		return 0;
 }
 
-static void vio_remove(struct mdesc_handle *hp, u64 node)
+static void vio_remove(struct mdesc_handle *hp, u64 node, const char *node_name)
 {
-	const char *type;
-	const u64 *id, *cfg_handle;
-	u64 a;
-	struct vio_md_node_query query;
+	struct vio_remove_node_data node_data;
 	struct device *dev;
 
-	type = mdesc_get_property(hp, node, "device-type", NULL);
-	if (!type) {
-		type = mdesc_get_property(hp, node, "name", NULL);
-		if (!type)
-			type = mdesc_node_name(hp, node);
-	}
-
-	query.type = type;
-
-	id = mdesc_get_property(hp, node, "id", NULL);
-	cfg_handle = NULL;
-	mdesc_for_each_arc(a, hp, node, MDESC_ARC_TYPE_BACK) {
-		u64 target;
+	node_data.hp = hp;
+	node_data.node = node;
 
-		target = mdesc_arc_target(hp, a);
-		cfg_handle = mdesc_get_property(hp, target,
-						"cfg-handle", NULL);
-		if (cfg_handle)
-			break;
-	}
-
-	if (!id) {
-		query.dev_no = ~(u64)0;
-		query.id = ~(u64)0;
-	} else if (!cfg_handle) {
-		query.dev_no = *id;
-		query.id = ~(u64)0;
-	} else {
-		query.dev_no = *cfg_handle;
-		query.id = *id;
-	}
-
-	dev = device_find_child(&root_vdev->dev, &query,
+	dev = device_find_child(&root_vdev->dev, (void *)&node_data,
 				vio_md_node_match);
 	if (dev) {
 		printk(KERN_INFO "VIO: Removing device %s\n", dev_name(dev));
@@ -423,15 +450,7 @@ static void vio_remove(struct mdesc_handle *hp, u64 node)
 		device_unregister(dev);
 		put_device(dev);
 	} else {
-		if (!id)
-			printk(KERN_ERR "VIO: Removed unknown %s node.\n",
-			       type);
-		else if (!cfg_handle)
-			printk(KERN_ERR "VIO: Removed unknown %s node %llu.\n",
-			       type, *id);
-		else
-			printk(KERN_ERR "VIO: Removed unknown %s node %llu-%llu.\n",
-			       type, *cfg_handle, *id);
+		pr_err("VIO: %s node not found in MDESC\n", node_name);
 	}
 }
 
@@ -446,7 +465,8 @@ static struct mdesc_notifier_client vio_device_notifier = {
  * under "openboot" that we should not mess with as aparently that is
  * reserved exclusively for OBP use.
  */
-static void vio_add_ds(struct mdesc_handle *hp, u64 node)
+static void vio_add_ds(struct mdesc_handle *hp, u64 node,
+		       const char *node_name)
 {
 	int found;
 	u64 a;
@@ -463,7 +483,7 @@ static void vio_add_ds(struct mdesc_handle *hp, u64 node)
 	}
 
 	if (found)
-		(void) vio_create_one(hp, node, &root_vdev->dev);
+		(void) vio_create_one(hp, node, node_name, &root_vdev->dev);
 }
 
 static struct mdesc_notifier_client vio_ds_notifier = {
@@ -530,7 +550,7 @@ static int __init vio_init(void)
 
 	cdev_cfg_handle = *cfg_handle;
 
-	root_vdev = vio_create_one(hp, root, NULL);
+	root_vdev = vio_create_one(hp, root, NULL, NULL);
 	err = -ENODEV;
 	if (!root_vdev) {
 		printk(KERN_ERR "VIO: Could not create root device.\n");

arch/sparc/kernel/viohs.c

@@ -223,6 +223,9 @@ static int send_rdx(struct vio_driver_state *vio)
 
 static int send_attr(struct vio_driver_state *vio)
 {
+	if (!vio->ops)
+		return -EINVAL;
+
 	return vio->ops->send_attr(vio);
 }
 
@@ -283,6 +286,7 @@ static int process_ver_info(struct vio_driver_state *vio,
 			ver.minor = vap->minor;
 		pkt->minor = ver.minor;
 		pkt->tag.stype = VIO_SUBTYPE_ACK;
+		pkt->dev_class = vio->dev_class;
 		viodbg(HS, "SEND VERSION ACK maj[%u] min[%u]\n",
 		       pkt->major, pkt->minor);
 		err = send_ctrl(vio, &pkt->tag, sizeof(*pkt));
@@ -374,6 +378,9 @@ static int process_attr(struct vio_driver_state *vio, void *pkt)
 	if (!(vio->hs_state & VIO_HS_GOTVERS))
 		return handshake_failure(vio);
 
+	if (!vio->ops)
+		return 0;
+
 	err = vio->ops->handle_attr(vio, pkt);
 	if (err < 0) {
 		return handshake_failure(vio);
@@ -388,6 +395,7 @@ static int process_attr(struct vio_driver_state *vio, void *pkt)
 			vio->hs_state |= VIO_HS_SENT_DREG;
 		}
 	}
+
 	return 0;
 }
 
@@ -647,10 +655,13 @@ int vio_control_pkt_engine(struct vio_driver_state *vio, void *pkt)
 		err = process_unknown(vio, pkt);
 		break;
 	}
+
 	if (!err &&
 	    vio->hs_state != prev_state &&
-	    (vio->hs_state & VIO_HS_COMPLETE))
+	    (vio->hs_state & VIO_HS_COMPLETE)) {
+		if (vio->ops)
 			vio->ops->handshake_complete(vio);
+	}
 
 	return err;
 }
@@ -765,7 +776,11 @@ void vio_port_up(struct vio_driver_state *vio)
 	}
 
 	if (!err) {
+		if (ldc_mode(vio->lp) == LDC_MODE_RAW)
+			ldc_set_state(vio->lp, LDC_STATE_CONNECTED);
+		else
 			err = ldc_connect(vio->lp);
+
 		if (err)
 			printk(KERN_WARNING "%s: Port %lu connect failed, "
 			       "err=%d\n",
@@ -805,8 +820,7 @@ int vio_driver_init(struct vio_driver_state *vio, struct vio_dev *vdev,
 		return -EINVAL;
 	}
 
-	if (!ops->send_attr ||
-	    !ops->handle_attr ||
+	if (!ops || !ops->send_attr || !ops->handle_attr ||
 	    !ops->handshake_complete)
 		return -EINVAL;