From 6429cd49f45450cd77a57b70b0dfa98fe2794da0 Mon Sep 17 00:00:00 2001 From: Alexandre Bounine Date: Wed, 27 Oct 2010 15:34:32 -0700 Subject: rapidio: add handling of orphan port-write message Add check for access to port-write (PW) message source device before processing the PW message. If source RIO device is not available (power down or RIO link failure) trace back to a last available switch/port on the PW message route and service failure at that point. Signed-off-by: Alexandre Bounine Cc: Thomas Moll Cc: Matt Porter Cc: Li Yang Cc: Kumar Gala Cc: Micha Nelissen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/rapidio/rio.c | 113 +++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 108 insertions(+), 5 deletions(-) (limited to 'drivers/rapidio/rio.c') diff --git a/drivers/rapidio/rio.c b/drivers/rapidio/rio.c index 77bd4165238f..aefc2a0004d4 100644 --- a/drivers/rapidio/rio.c +++ b/drivers/rapidio/rio.c @@ -494,6 +494,92 @@ int rio_set_port_lockout(struct rio_dev *rdev, u32 pnum, int lock) return 0; } +/** + * rio_chk_dev_route - Validate route to the specified device. + * @rdev: RIO device failed to respond + * @nrdev: Last active device on the route to rdev + * @npnum: nrdev's port number on the route to rdev + * + * Follows a route to the specified RIO device to determine the last available + * device (and corresponding RIO port) on the route. + */ +static int +rio_chk_dev_route(struct rio_dev *rdev, struct rio_dev **nrdev, int *npnum) +{ + u32 result; + int p_port, rc = -EIO; + struct rio_dev *prev = NULL; + + /* Find switch with failed RIO link */ + while (rdev->prev && (rdev->prev->pef & RIO_PEF_SWITCH)) { + if (!rio_read_config_32(rdev->prev, RIO_DEV_ID_CAR, &result)) { + prev = rdev->prev; + break; + } + rdev = rdev->prev; + } + + if (prev == NULL) + goto err_out; + + /* Find port with failed RIO link */ + for (p_port = 0; + p_port < RIO_GET_TOTAL_PORTS(prev->swpinfo); p_port++) + if (prev->rswitch->nextdev[p_port] == rdev) + break; + + if (p_port < RIO_GET_TOTAL_PORTS(prev->swpinfo)) { + pr_debug("RIO: link failed on [%s]-P%d\n", + rio_name(prev), p_port); + *nrdev = prev; + *npnum = p_port; + rc = 0; + } else + pr_debug("RIO: failed to trace route to %s\n", rio_name(prev)); +err_out: + return rc; +} + +/** + * rio_mport_chk_dev_access - Validate access to the specified device. + * @mport: Master port to send transactions + * @destid: Device destination ID in network + * @hopcount: Number of hops into the network + */ +static int +rio_mport_chk_dev_access(struct rio_mport *mport, u16 destid, u8 hopcount) +{ + int i = 0; + u32 tmp; + + while (rio_mport_read_config_32(mport, destid, hopcount, + RIO_DEV_ID_CAR, &tmp)) { + i++; + if (i == RIO_MAX_CHK_RETRY) + return -EIO; + mdelay(1); + } + + return 0; +} + +/** + * rio_chk_dev_access - Validate access to the specified device. + * @rdev: Pointer to RIO device control structure + */ +static int rio_chk_dev_access(struct rio_dev *rdev) +{ + u8 hopcount = 0xff; + u16 destid = rdev->destid; + + if (rdev->rswitch) { + destid = rdev->rswitch->destid; + hopcount = rdev->rswitch->hopcount; + } + + return rio_mport_chk_dev_access(rdev->net->hport, destid, hopcount); +} + /** * rio_get_input_status - Sends a Link-Request/Input-Status control symbol and * returns link-response (if requested). @@ -654,8 +740,8 @@ int rio_inb_pwrite_handler(union rio_pw_msg *pw_msg) rdev = rio_get_comptag(pw_msg->em.comptag, NULL); if (rdev == NULL) { - /* Someting bad here (probably enumeration error) */ - pr_err("RIO: %s No matching device for CTag 0x%08x\n", + /* Device removed or enumeration error */ + pr_debug("RIO: %s No matching device for CTag 0x%08x\n", __func__, pw_msg->em.comptag); return -EIO; } @@ -686,6 +772,26 @@ int rio_inb_pwrite_handler(union rio_pw_msg *pw_msg) return 0; } + portnum = pw_msg->em.is_port & 0xFF; + + /* Check if device and route to it are functional: + * Sometimes devices may send PW message(s) just before being + * powered down (or link being lost). + */ + if (rio_chk_dev_access(rdev)) { + pr_debug("RIO: device access failed - get link partner\n"); + /* Scan route to the device and identify failed link. + * This will replace device and port reported in PW message. + * PW message should not be used after this point. + */ + if (rio_chk_dev_route(rdev, &rdev, &portnum)) { + pr_err("RIO: Route trace for %s failed\n", + rio_name(rdev)); + return -EIO; + } + pw_msg = NULL; + } + /* For End-point devices processing stops here */ if (!(rdev->pef & RIO_PEF_SWITCH)) return 0; @@ -703,9 +809,6 @@ int rio_inb_pwrite_handler(union rio_pw_msg *pw_msg) /* * Process the port-write notification from switch */ - - portnum = pw_msg->em.is_port & 0xFF; - if (rdev->rswitch->em_handle) rdev->rswitch->em_handle(rdev, portnum); -- cgit v1.2.1