forcedeth: msi interrupts
Add a workaround for lost MSI interrupts. There is a race condition in
the HW in which future interrupts could be missed. The workaround is to
toggle the MSI irq mask.
Added cleanup based on comments from Andrew Morton.
Signed-off-by: Ayaz Abdulla <aabdulla@nvidia.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/net/forcedeth.c b/drivers/net/forcedeth.c
index 9eca97f..2cb2447 100644
--- a/drivers/net/forcedeth.c
+++ b/drivers/net/forcedeth.c
@@ -3273,6 +3273,20 @@
dprintk(KERN_DEBUG "%s: link change notification done.\n", dev->name);
}
+static void nv_msi_workaround(struct fe_priv *np)
+{
+
+ /* Need to toggle the msi irq mask within the ethernet device,
+ * otherwise, future interrupts will not be detected.
+ */
+ if (np->msi_flags & NV_MSI_ENABLED) {
+ u8 __iomem *base = np->base;
+
+ writel(0, base + NvRegMSIIrqMask);
+ writel(NVREG_MSI_VECTOR_0_ENABLED, base + NvRegMSIIrqMask);
+ }
+}
+
static irqreturn_t nv_nic_irq(int foo, void *data)
{
struct net_device *dev = (struct net_device *) data;
@@ -3295,6 +3309,8 @@
if (!(events & np->irqmask))
break;
+ nv_msi_workaround(np);
+
spin_lock(&np->lock);
nv_tx_done(dev);
spin_unlock(&np->lock);
@@ -3410,6 +3426,8 @@
if (!(events & np->irqmask))
break;
+ nv_msi_workaround(np);
+
spin_lock(&np->lock);
nv_tx_done_optimized(dev, TX_WORK_PER_LOOP);
spin_unlock(&np->lock);
@@ -3750,6 +3768,8 @@
if (!(events & NVREG_IRQ_TIMER))
return IRQ_RETVAL(0);
+ nv_msi_workaround(np);
+
spin_lock(&np->lock);
np->intr_test = 1;
spin_unlock(&np->lock);
