From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.tundra.com (mail2.tundra.com [142.46.200.162]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mail.tundra.com", Issuer "mail.tundra.com" (not verified)) by ozlabs.org (Postfix) with ESMTPS id 0DF2FB7C98 for ; Thu, 25 Feb 2010 02:21:11 +1100 (EST) Date: Wed, 24 Feb 2010 10:20:50 -0500 From: Alexandre Bounine To: mporter@kernel.crashing.org Subject: [PATCH 2/7] RapidIO: Add switch locking during discovery Message-ID: <20100224152050.GB13661@kaneng01.tundra.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: abounine@idt.com, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, thomas.moll.ext@nsn.com, thomas.moll@sysgo.com List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Alexandre Bounine 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 --- rio-scan.c | 88 ++++++++++++++++++++++++++++++++++++++++++++++++++++++------- 1 files changed, 79 insertions(+), 9 deletions(-) diff -x '*.pj' -X dontdiff_2.6.32-rc5 -pNur w33r7a/drivers/rapidio/rio-scan.c w33r7b/drivers/rapidio/rio-scan.c --- w33r7a/drivers/rapidio/rio-scan.c 2010-02-09 15:11:09.141972000 -0500 +++ w33r7b/drivers/rapidio/rio-scan.c 2010-02-10 16:13:56.382802000 -0500 @@ -750,6 +750,7 @@ rio_disc_peer(struct rio_net *net, struc int num_ports; struct rio_dev *rdev; u16 ndestid; + u32 result; /* Setup new RIO device */ if ((rdev = rio_setup_device(net, port, destid, hopcount, 0))) { @@ -778,6 +779,27 @@ rio_disc_peer(struct rio_net *net, struc pr_debug( "RIO: scanning device on port %d\n", port_num); + + /* 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) { + /* Delay a bit */ + mdelay(1); + /* 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); + } + for (ndestid = 0; ndestid < RIO_ANY_DESTID(port->sys_size); ndestid++) { @@ -789,6 +811,19 @@ rio_disc_peer(struct rio_net *net, struc break; } + /* 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_info("RIO: badness when releasing " \ + "host lock on %s\n", + rio_name(rdev)); + } + if (rio_disc_peer (net, port, ndestid, hopcount + 1) < 0) return -1; @@ -958,17 +993,45 @@ static void rio_build_route_tables(void) struct rio_dev *rdev; int i; u8 sport; + u32 result; 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)) { + /* Attempt to acquire device lock */ + rio_write_config_32(rdev, RIO_HOST_DID_LOCK_CSR, + rdev->net->hport->host_deviceid); + rio_read_config_32(rdev, + RIO_HOST_DID_LOCK_CSR, &result); + while (result != rdev->net->hport->host_deviceid) { + /* Delay a bit */ + mdelay(1); + /* Attempt to acquire device lock again */ + rio_write_config_32(rdev, RIO_HOST_DID_LOCK_CSR, + rdev->net->hport->host_deviceid); + rio_read_config_32(rdev, + RIO_HOST_DID_LOCK_CSR, &result); + } + + 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; + } + + /* Release device lock */ + rio_write_config_32(rdev, RIO_HOST_DID_LOCK_CSR, + rdev->net->hport->host_deviceid); + rio_read_config_32(rdev, + RIO_HOST_DID_LOCK_CSR, &result); + if ((result & 0xffff) != 0xffff) { + pr_info("RIO: badness when releasing " \ + "host lock on %s\n", rio_name(rdev)); + } + } } @@ -1027,6 +1090,13 @@ int __devinit rio_disc_mport(struct rio_ 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 --- Important Notice: This message is intended for the use of the individual to whom it is addressed and may contain information which is privileged, confidential and/or exempt from disclosure under applicable law. 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