From 3670e7e12e582c6d67761275d148171feb7a9004 Mon Sep 17 00:00:00 2001 From: Alexandre Bounine Date: Tue, 21 Aug 2012 16:16:11 -0700 Subject: rapidio/tsi721: fix inbound doorbell interrupt handling Make sure that there is no doorbell messages left behind due to disabled interrupts during inbound doorbell processing. The most common case for this bug is loss of rionet JOIN messages in systems with three or more rionet participants and MSI or MSI-X enabled. As result, requests for packet transfers may finish with "destination unreachable" error message. This patch is applicable to kernel versions starting from v3.2. Signed-off-by: Alexandre Bounine Cc: Matt Porter Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/rapidio/devices/tsi721.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'drivers/rapidio') diff --git a/drivers/rapidio/devices/tsi721.c b/drivers/rapidio/devices/tsi721.c index 722246cf20ab..c0d6a049cbd6 100644 --- a/drivers/rapidio/devices/tsi721.c +++ b/drivers/rapidio/devices/tsi721.c @@ -435,6 +435,9 @@ static void tsi721_db_dpc(struct work_struct *work) " info %4.4x\n", DBELL_SID(idb.bytes), DBELL_TID(idb.bytes), DBELL_INF(idb.bytes)); } + + wr_ptr = ioread32(priv->regs + + TSI721_IDQ_WP(IDB_QUEUE)) % IDB_QSIZE; } iowrite32(rd_ptr & (IDB_QSIZE - 1), @@ -445,6 +448,10 @@ static void tsi721_db_dpc(struct work_struct *work) regval |= TSI721_SR_CHINT_IDBQRCV; iowrite32(regval, priv->regs + TSI721_SR_CHINTE(IDB_QUEUE)); + + wr_ptr = ioread32(priv->regs + TSI721_IDQ_WP(IDB_QUEUE)) % IDB_QSIZE; + if (wr_ptr != rd_ptr) + schedule_work(&priv->idb_work); } /** -- cgit v1.2.3-59-g8ed1b