[PATCH] RapidIO: Fix hang on RapidIO doorbell queue full condition

From: Thomas Taranowski
Date: Tue Jan 04 2011 - 02:30:16 EST

In fsl_rio_dbell_handler, the code currently simply acknowledges the QFI queue
full interrupt, but does nothing to resolve the queue full condition. Instead,
it jumps to the end of the isr. When a queue full condition occurs, the isr is
then re-entered immediately and continually, forever.

The fix is to just fall through and read out current doorbell entries.

Tested against 2.6.26-rc8 on a p2020

Signed-off-by: Thomas Taranowski <tom@xxxxxxxxxxxxxxx>
arch/powerpc/sysdev/fsl_rio.c | 1 -
1 files changed, 0 insertions(+), 1 deletions(-)

diff --git a/arch/powerpc/sysdev/fsl_rio.c b/arch/powerpc/sysdev/fsl_rio.c
index 9725369..9f99bef 100644
--- a/arch/powerpc/sysdev/fsl_rio.c
+++ b/arch/powerpc/sysdev/fsl_rio.c
@@ -973,7 +973,6 @@ fsl_rio_dbell_handler(int irq, void *dev_instance)
if (dsr & DOORBELL_DSR_QFI) {
pr_info("RIO: doorbell queue full\n");
out_be32(&priv->msg_regs->dsr, DOORBELL_DSR_QFI);
- goto out;

/* XXX Need to check/dispatch until queue empty */

Thomas Taranowski
Certified netburner consultant
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