summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorAlexandre Bounine <alexandre.bounine@idt.com>2013-05-24 15:55:17 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2013-05-24 16:22:51 -0700
commit1ccc819da6fda9bee10ab8b72e9adbb5ad3e4959 (patch)
treeffe3a4cc65e4061d78cc093c705b39321a059e95
parentfb09c3733a94b5f1dba50359d09c9e217c763fb9 (diff)
downloadlinux-3.10-1ccc819da6fda9bee10ab8b72e9adbb5ad3e4959.tar.gz
linux-3.10-1ccc819da6fda9bee10ab8b72e9adbb5ad3e4959.tar.bz2
linux-3.10-1ccc819da6fda9bee10ab8b72e9adbb5ad3e4959.zip
rapidio/tsi721: fix bug in MSI interrupt handling
Fix bug in MSI interrupt handling which causes loss of event notifications. Typical indication of lost MSI interrupts are stalled message and doorbell transfers between RapidIO endpoints. To avoid loss of MSI interrupts all interrupts from the device must be disabled on entering the interrupt handler routine and re-enabled when exiting it. Re-enabling device interrupts will trigger new MSI message(s) if Tsi721 registered new events since entering interrupt handler routine. This patch is applicable to kernel versions starting from v3.2. Signed-off-by: Alexandre Bounine <alexandre.bounine@idt.com> Cc: Matt Porter <mporter@kernel.crashing.org> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-rw-r--r--drivers/rapidio/devices/tsi721.c12
1 files changed, 12 insertions, 0 deletions
diff --git a/drivers/rapidio/devices/tsi721.c b/drivers/rapidio/devices/tsi721.c
index 6faba406b6e..a8b2c23a7ef 100644
--- a/drivers/rapidio/devices/tsi721.c
+++ b/drivers/rapidio/devices/tsi721.c
@@ -471,6 +471,10 @@ static irqreturn_t tsi721_irqhandler(int irq, void *ptr)
u32 intval;
u32 ch_inte;
+ /* For MSI mode disable all device-level interrupts */
+ if (priv->flags & TSI721_USING_MSI)
+ iowrite32(0, priv->regs + TSI721_DEV_INTE);
+
dev_int = ioread32(priv->regs + TSI721_DEV_INT);
if (!dev_int)
return IRQ_NONE;
@@ -560,6 +564,14 @@ static irqreturn_t tsi721_irqhandler(int irq, void *ptr)
}
}
#endif
+
+ /* For MSI mode re-enable device-level interrupts */
+ if (priv->flags & TSI721_USING_MSI) {
+ dev_int = TSI721_DEV_INT_SR2PC_CH | TSI721_DEV_INT_SRIO |
+ TSI721_DEV_INT_SMSG_CH | TSI721_DEV_INT_BDMA_CH;
+ iowrite32(dev_int, priv->regs + TSI721_DEV_INTE);
+ }
+
return IRQ_HANDLED;
}