From 818a04a0bb93643d57dd8935815de2ff307b58a3 Mon Sep 17 00:00:00 2001 From: Alexandre Bounine Date: Wed, 26 May 2010 14:43:58 -0700 Subject: [PATCH] rapidio: add switch locking during discovery Add switch access locking during RapidIO discovery. Access lock is required when reading switch routing table contents due to indexed mechanism of RT addressing. Signed-off-by: Alexandre Bounine Tested-by: Thomas Moll Cc: Matt Porter Cc: Li Yang Cc: Kumar Gala Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/rapidio/rio-scan.c | 164 ++++++++++++++++++++++++++++++++----- 1 file changed, 144 insertions(+), 20 deletions(-) diff --git a/drivers/rapidio/rio-scan.c b/drivers/rapidio/rio-scan.c index 7f1a675d835d..cbf0d5f4fba8 100644 --- a/drivers/rapidio/rio-scan.c +++ b/drivers/rapidio/rio-scan.c @@ -456,6 +456,80 @@ rio_sport_is_active(struct rio_mport *port, u16 destid, u8 hopcount, int sport) return (result & PORT_N_ERR_STS_PORT_OK); } +/** + * rio_lock_device - Acquires host device lock for specified device + * @port: Master port to send transaction + * @destid: Destination ID for device/switch + * @hopcount: Hopcount to reach switch + * @wait_ms: Max wait time in msec (0 = no timeout) + * + * Attepts to acquire host device lock for specified device + * Returns 0 if device lock acquired or EINVAL if timeout expires. + */ +static int +rio_lock_device(struct rio_mport *port, u16 destid, u8 hopcount, int wait_ms) +{ + u32 result; + int tcnt = 0; + + /* Attempt to acquire device lock */ + rio_mport_write_config_32(port, destid, hopcount, + RIO_HOST_DID_LOCK_CSR, port->host_deviceid); + rio_mport_read_config_32(port, destid, hopcount, + RIO_HOST_DID_LOCK_CSR, &result); + + while (result != port->host_deviceid) { + if (wait_ms != 0 && tcnt == wait_ms) { + pr_debug("RIO: timeout when locking device %x:%x\n", + destid, hopcount); + return -EINVAL; + } + + /* Delay a bit */ + mdelay(1); + tcnt++; + /* Try to acquire device lock again */ + rio_mport_write_config_32(port, destid, + hopcount, + RIO_HOST_DID_LOCK_CSR, + port->host_deviceid); + rio_mport_read_config_32(port, destid, + hopcount, + RIO_HOST_DID_LOCK_CSR, &result); + } + + return 0; +} + +/** + * rio_unlock_device - Releases host device lock for specified device + * @port: Master port to send transaction + * @destid: Destination ID for device/switch + * @hopcount: Hopcount to reach switch + * + * Returns 0 if device lock released or EINVAL if fails. + */ +static int +rio_unlock_device(struct rio_mport *port, u16 destid, u8 hopcount) +{ + u32 result; + + /* Release device lock */ + rio_mport_write_config_32(port, destid, + hopcount, + RIO_HOST_DID_LOCK_CSR, + port->host_deviceid); + rio_mport_read_config_32(port, destid, hopcount, + RIO_HOST_DID_LOCK_CSR, &result); + if ((result & 0xffff) != 0xffff) { + pr_debug("RIO: badness when releasing device lock %x:%x\n", + destid, hopcount); + return -EINVAL; + } + + return 0; +} + /** * rio_route_add_entry- Add a route entry to a switch routing table * @mport: Master port to send transaction @@ -463,6 +537,7 @@ rio_sport_is_active(struct rio_mport *port, u16 destid, u8 hopcount, int sport) * @table: Routing table ID * @route_destid: Destination ID to be routed * @route_port: Port number to be routed + * @lock: lock switch device flag * * Calls the switch specific add_entry() method to add a route entry * on a switch. The route table can be specified using the @table @@ -471,12 +546,26 @@ rio_sport_is_active(struct rio_mport *port, u16 destid, u8 hopcount, int sport) * %RIO_GLOBAL_TABLE in @table. Returns %0 on success or %-EINVAL * on failure. */ -static int rio_route_add_entry(struct rio_mport *mport, struct rio_switch *rswitch, - u16 table, u16 route_destid, u8 route_port) +static int +rio_route_add_entry(struct rio_mport *mport, struct rio_switch *rswitch, + u16 table, u16 route_destid, u8 route_port, int lock) { - return rswitch->add_entry(mport, rswitch->destid, + int rc; + + if (lock) { + rc = rio_lock_device(mport, rswitch->destid, + rswitch->hopcount, 1000); + if (rc) + return rc; + } + + rc = rswitch->add_entry(mport, rswitch->destid, rswitch->hopcount, table, route_destid, route_port); + if (lock) + rio_unlock_device(mport, rswitch->destid, rswitch->hopcount); + + return rc; } /** @@ -486,6 +575,7 @@ static int rio_route_add_entry(struct rio_mport *mport, struct rio_switch *rswit * @table: Routing table ID * @route_destid: Destination ID to be routed * @route_port: Pointer to read port number into + * @lock: lock switch device flag * * Calls the switch specific get_entry() method to read a route entry * in a switch. The route table can be specified using the @table @@ -496,11 +586,24 @@ static int rio_route_add_entry(struct rio_mport *mport, struct rio_switch *rswit */ static int rio_route_get_entry(struct rio_mport *mport, struct rio_switch *rswitch, u16 table, - u16 route_destid, u8 * route_port) + u16 route_destid, u8 *route_port, int lock) { - return rswitch->get_entry(mport, rswitch->destid, + int rc; + + if (lock) { + rc = rio_lock_device(mport, rswitch->destid, + rswitch->hopcount, 1000); + if (rc) + return rc; + } + + rc = rswitch->get_entry(mport, rswitch->destid, rswitch->hopcount, table, route_destid, route_port); + if (lock) + rio_unlock_device(mport, rswitch->destid, rswitch->hopcount); + + return rc; } /** @@ -640,14 +743,14 @@ static int __devinit rio_enum_peer(struct rio_net *net, struct rio_mport *port, sw_inport = rio_get_swpinfo_inport(port, RIO_ANY_DESTID(port->sys_size), hopcount); rio_route_add_entry(port, rdev->rswitch, RIO_GLOBAL_TABLE, - port->host_deviceid, sw_inport); + 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(port, rdev->rswitch, RIO_GLOBAL_TABLE, - destid, sw_inport); + destid, sw_inport, 0); rdev->rswitch->route_table[destid] = sw_inport; } @@ -673,7 +776,7 @@ static int __devinit rio_enum_peer(struct rio_net *net, struct rio_mport *port, rio_route_add_entry(port, rdev->rswitch, RIO_GLOBAL_TABLE, RIO_ANY_DESTID(port->sys_size), - port_num); + port_num, 0); if (rio_enum_peer(net, port, hopcount + 1) < 0) return -1; @@ -687,7 +790,8 @@ static int __devinit rio_enum_peer(struct rio_net *net, struct rio_mport *port, rio_route_add_entry(port, rdev->rswitch, RIO_GLOBAL_TABLE, destid, - port_num); + port_num, + 0); rdev->rswitch-> route_table[destid] = port_num; @@ -778,17 +882,21 @@ rio_disc_peer(struct rio_net *net, struct rio_mport *port, u16 destid, pr_debug( "RIO: scanning device on port %d\n", port_num); + + rio_lock_device(port, destid, hopcount, 1000); + for (ndestid = 0; ndestid < RIO_ANY_DESTID(port->sys_size); ndestid++) { rio_route_get_entry(port, rdev->rswitch, RIO_GLOBAL_TABLE, ndestid, - &route_port); + &route_port, 0); if (route_port == port_num) break; } + rio_unlock_device(port, destid, hopcount); if (rio_disc_peer (net, port, ndestid, hopcount + 1) < 0) return -1; @@ -889,7 +997,9 @@ static void rio_update_route_tables(struct rio_mport *port) rswitch->destid, rswitch->hopcount); if (rswitch->add_entry) { - rio_route_add_entry(port, rswitch, RIO_GLOBAL_TABLE, destid, sport); + rio_route_add_entry(port, rswitch, + RIO_GLOBAL_TABLE, destid, + sport, 0); rswitch->route_table[destid] = sport; } } @@ -963,15 +1073,22 @@ static void rio_build_route_tables(void) u8 sport; list_for_each_entry(rdev, &rio_devices, global_list) - if (rio_is_switch(rdev)) - for (i = 0; - i < RIO_MAX_ROUTE_ENTRIES(rdev->net->hport->sys_size); - i++) { - if (rio_route_get_entry - (rdev->net->hport, rdev->rswitch, RIO_GLOBAL_TABLE, - i, &sport) < 0) - continue; - rdev->rswitch->route_table[i] = sport; + if (rio_is_switch(rdev)) { + rio_lock_device(rdev->net->hport, rdev->rswitch->destid, + rdev->rswitch->hopcount, 1000); + for (i = 0; + i < RIO_MAX_ROUTE_ENTRIES(rdev->net->hport->sys_size); + i++) { + if (rio_route_get_entry + (rdev->net->hport, rdev->rswitch, + RIO_GLOBAL_TABLE, i, &sport, 0) < 0) + continue; + rdev->rswitch->route_table[i] = sport; + } + + rio_unlock_device(rdev->net->hport, + rdev->rswitch->destid, + rdev->rswitch->hopcount); } } @@ -1030,6 +1147,13 @@ int __devinit rio_disc_mport(struct rio_mport *mport) del_timer_sync(&rio_enum_timer); pr_debug("done\n"); + + /* Read DestID assigned by enumerator */ + rio_local_read_config_32(mport, RIO_DID_CSR, + &mport->host_deviceid); + mport->host_deviceid = RIO_GET_DID(mport->sys_size, + mport->host_deviceid); + if (rio_disc_peer(net, mport, RIO_ANY_DESTID(mport->sys_size), 0) < 0) { printk(KERN_INFO -- 2.39.2