rapidio: add destination ID allocation mechanism
Replace the single global destination ID counter with per-net allocation
mechanism to allow independent destID management for each available
RapidIO network. Using bitmap based mechanism instead of counters allows
destination ID release and reuse in systems that support hot-swap.
Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Li Yang <leoli@freescale.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/rapidio/rio-scan.c b/drivers/rapidio/rio-scan.c
index 745670f..48e9041 100644
--- a/drivers/rapidio/rio-scan.c
+++ b/drivers/rapidio/rio-scan.c
@@ -54,6 +54,114 @@
-1,
};
+
+/*
+ * rio_destid_alloc - Allocate next available destID for given network
+ * net: RIO network
+ *
+ * Returns next available device destination ID for the specified RIO network.
+ * Marks allocated ID as one in use.
+ * Returns RIO_INVALID_DESTID if new destID is not available.
+ */
+static u16 rio_destid_alloc(struct rio_net *net)
+{
+ int destid;
+ struct rio_id_table *idtab = &net->destid_table;
+
+ spin_lock(&idtab->lock);
+ destid = find_next_zero_bit(idtab->table, idtab->max, idtab->next);
+ if (destid >= idtab->max)
+ destid = find_first_zero_bit(idtab->table, idtab->max);
+
+ if (destid < idtab->max) {
+ idtab->next = destid + 1;
+ if (idtab->next >= idtab->max)
+ idtab->next = 0;
+ set_bit(destid, idtab->table);
+ destid += idtab->start;
+ } else
+ destid = RIO_INVALID_DESTID;
+
+ spin_unlock(&idtab->lock);
+ return (u16)destid;
+}
+
+/*
+ * rio_destid_reserve - Reserve the specivied destID
+ * net: RIO network
+ * destid: destID to reserve
+ *
+ * Tries to reserve the specified destID.
+ * Returns 0 if successfull.
+ */
+static int rio_destid_reserve(struct rio_net *net, u16 destid)
+{
+ int oldbit;
+ struct rio_id_table *idtab = &net->destid_table;
+
+ destid -= idtab->start;
+ spin_lock(&idtab->lock);
+ oldbit = test_and_set_bit(destid, idtab->table);
+ spin_unlock(&idtab->lock);
+ return oldbit;
+}
+
+/*
+ * rio_destid_free - free a previously allocated destID
+ * net: RIO network
+ * destid: destID to free
+ *
+ * Makes the specified destID available for use.
+ */
+static void rio_destid_free(struct rio_net *net, u16 destid)
+{
+ struct rio_id_table *idtab = &net->destid_table;
+
+ destid -= idtab->start;
+ spin_lock(&idtab->lock);
+ clear_bit(destid, idtab->table);
+ spin_unlock(&idtab->lock);
+}
+
+/*
+ * rio_destid_first - return first destID in use
+ * net: RIO network
+ */
+static u16 rio_destid_first(struct rio_net *net)
+{
+ int destid;
+ struct rio_id_table *idtab = &net->destid_table;
+
+ spin_lock(&idtab->lock);
+ destid = find_first_bit(idtab->table, idtab->max);
+ if (destid >= idtab->max)
+ destid = RIO_INVALID_DESTID;
+ else
+ destid += idtab->start;
+ spin_unlock(&idtab->lock);
+ return (u16)destid;
+}
+
+/*
+ * rio_destid_next - return next destID in use
+ * net: RIO network
+ * from: destination ID from which search shall continue
+ */
+static u16 rio_destid_next(struct rio_net *net, u16 from)
+{
+ int destid;
+ struct rio_id_table *idtab = &net->destid_table;
+
+ spin_lock(&idtab->lock);
+ destid = find_next_bit(idtab->table, idtab->max, from);
+ if (destid >= idtab->max)
+ destid = RIO_INVALID_DESTID;
+ else
+ destid += idtab->start;
+ spin_unlock(&idtab->lock);
+ return (u16)destid;
+}
+
/**
* rio_get_device_id - Get the base/extended device id for a device
* @port: RIO master port
@@ -171,10 +279,6 @@
/* Set master port destid and init destid ctr */
rio_local_set_device_id(port, port->host_deviceid);
-
- if (next_destid == port->host_deviceid)
- next_destid++;
-
return 0;
}
@@ -441,9 +545,8 @@
if (rio_device_has_destid(port, rdev->src_ops, rdev->dst_ops)) {
if (do_enum) {
rio_set_device_id(port, destid, hopcount, next_destid);
- rdev->destid = next_destid++;
- if (next_destid == port->host_deviceid)
- next_destid++;
+ rdev->destid = next_destid;
+ next_destid = rio_destid_alloc(net);
} else
rdev->destid = rio_get_device_id(port, destid, hopcount);
@@ -742,12 +845,7 @@
static int __devinit rio_enum_peer(struct rio_net *net, struct rio_mport *port,
u8 hopcount, struct rio_dev *prev, int prev_port)
{
- int port_num;
- int cur_destid;
- int sw_destid;
- int sw_inport;
struct rio_dev *rdev;
- u16 destid;
u32 regval;
int tmp;
@@ -813,19 +911,26 @@
return -1;
if (rio_is_switch(rdev)) {
+ int sw_destid;
+ int cur_destid;
+ int sw_inport;
+ u16 destid;
+ int port_num;
+
sw_inport = RIO_GET_PORT_NUM(rdev->swpinfo);
rio_route_add_entry(rdev, RIO_GLOBAL_TABLE,
port->host_deviceid, sw_inport, 0);
rdev->rswitch->route_table[port->host_deviceid] = sw_inport;
- for (destid = 0; destid < next_destid; destid++) {
- if (destid == port->host_deviceid)
- continue;
- rio_route_add_entry(rdev, RIO_GLOBAL_TABLE,
- destid, sw_inport, 0);
- rdev->rswitch->route_table[destid] = sw_inport;
+ destid = rio_destid_first(net);
+ while (destid != RIO_INVALID_DESTID && destid < next_destid) {
+ if (destid != port->host_deviceid) {
+ rio_route_add_entry(rdev, RIO_GLOBAL_TABLE,
+ destid, sw_inport, 0);
+ rdev->rswitch->route_table[destid] = sw_inport;
+ }
+ destid = rio_destid_next(net, destid + 1);
}
-
pr_debug(
"RIO: found %s (vid %4.4x did %4.4x) with %d ports\n",
rio_name(rdev), rdev->vid, rdev->did,
@@ -863,19 +968,22 @@
return -1;
/* Update routing tables */
- if (next_destid > cur_destid) {
+ destid = rio_destid_next(net, cur_destid + 1);
+ if (destid != RIO_INVALID_DESTID) {
for (destid = cur_destid;
- destid < next_destid; destid++) {
- if (destid == port->host_deviceid)
- continue;
- rio_route_add_entry(rdev,
+ destid < next_destid;) {
+ if (destid != port->host_deviceid) {
+ rio_route_add_entry(rdev,
RIO_GLOBAL_TABLE,
destid,
port_num,
0);
- rdev->rswitch->
- route_table[destid] =
- port_num;
+ rdev->rswitch->
+ route_table[destid] =
+ port_num;
+ }
+ destid = rio_destid_next(net,
+ destid + 1);
}
}
} else {
@@ -901,11 +1009,8 @@
rio_init_em(rdev);
/* Check for empty switch */
- if (next_destid == sw_destid) {
- next_destid++;
- if (next_destid == port->host_deviceid)
- next_destid++;
- }
+ if (next_destid == sw_destid)
+ next_destid = rio_destid_alloc(net);
rdev->destid = sw_destid;
} else
@@ -1043,17 +1148,39 @@
/**
* rio_alloc_net- Allocate and configure a new RIO network
* @port: Master port associated with the RIO network
+ * @do_enum: Enumeration/Discovery mode flag
+ * @start: logical minimal start id for new net
*
* Allocates a RIO network structure, initializes per-network
* list heads, and adds the associated master port to the
* network list of associated master ports. Returns a
* RIO network pointer on success or %NULL on failure.
*/
-static struct rio_net __devinit *rio_alloc_net(struct rio_mport *port)
+static struct rio_net __devinit *rio_alloc_net(struct rio_mport *port,
+ int do_enum, u16 start)
{
struct rio_net *net;
net = kzalloc(sizeof(struct rio_net), GFP_KERNEL);
+ if (net && do_enum) {
+ net->destid_table.table = kzalloc(
+ BITS_TO_LONGS(RIO_MAX_ROUTE_ENTRIES(port->sys_size)) *
+ sizeof(long),
+ GFP_KERNEL);
+
+ if (net->destid_table.table == NULL) {
+ pr_err("RIO: failed to allocate destID table\n");
+ kfree(net);
+ net = NULL;
+ } else {
+ net->destid_table.start = start;
+ net->destid_table.next = 0;
+ net->destid_table.max =
+ RIO_MAX_ROUTE_ENTRIES(port->sys_size);
+ spin_lock_init(&net->destid_table.lock);
+ }
+ }
+
if (net) {
INIT_LIST_HEAD(&net->node);
INIT_LIST_HEAD(&net->devices);
@@ -1163,12 +1290,16 @@
/* If master port has an active link, allocate net and enum peers */
if (rio_mport_is_active(mport)) {
- if (!(net = rio_alloc_net(mport))) {
+ net = rio_alloc_net(mport, 1, 0);
+ if (!net) {
printk(KERN_ERR "RIO: failed to allocate new net\n");
rc = -ENOMEM;
goto out;
}
+ /* reserve mport destID in new net */
+ rio_destid_reserve(net, mport->host_deviceid);
+
/* Enable Input Output Port (transmitter reviever) */
rio_enable_rx_tx_port(mport, 1, 0, 0, 0);
@@ -1176,6 +1307,8 @@
rio_local_write_config_32(mport, RIO_COMPONENT_TAG_CSR,
next_comptag++);
+ next_destid = rio_destid_alloc(net);
+
if (rio_enum_peer(net, mport, 0, NULL, 0) < 0) {
/* A higher priority host won enumeration, bail. */
printk(KERN_INFO
@@ -1185,6 +1318,8 @@
rc = -EBUSY;
goto out;
}
+ /* free the last allocated destID (unused) */
+ rio_destid_free(net, next_destid);
rio_update_route_tables(net);
rio_clear_locks(net);
rio_pw_enable(mport, 1);
@@ -1265,7 +1400,7 @@
enum_done:
pr_debug("RIO: ... enumeration done\n");
- net = rio_alloc_net(mport);
+ net = rio_alloc_net(mport, 0, 0);
if (!net) {
printk(KERN_ERR "RIO: Failed to allocate new net\n");
goto bail;