From: Stephen Hemminger <shemminger@osdl.org>
Date: Wed, 22 Feb 2006 19:45:00 +0000 (-0800)
Subject: [PATCH] sky2: poke coalescing timer to fix hang
X-Git-Tag: v2.6.16-rc5~53^2~1^2~8
X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a8fd6266dafd564bae6758cb78c8c152e7d4115e;p=linux-2.6

[PATCH] sky2: poke coalescing timer to fix hang

Need to restart the interrupt coalescing timer after clearing the interrupt,
to avoid races with interrupt timer and processing.

Patch from Carl-Daniel Halfinger

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
---

diff --git a/drivers/net/sky2.c b/drivers/net/sky2.c
index cf7fd28d67..629809433c 100644
--- a/drivers/net/sky2.c
+++ b/drivers/net/sky2.c
@@ -1895,6 +1895,17 @@ static int sky2_poll(struct net_device *dev0, int *budget)
 
 	sky2_write32(hw, STAT_CTRL, SC_STAT_CLR_IRQ);
 
+	/*
+	 * Kick the STAT_LEV_TIMER_CTRL timer.
+	 * This fixes my hangs on Yukon-EC (0xb6) rev 1.
+	 * The if clause is there to start the timer only if it has been
+	 * configured correctly and not been disabled via ethtool.
+	 */
+	if (sky2_read8(hw, STAT_LEV_TIMER_CTRL) == TIM_START) {
+		sky2_write8(hw, STAT_LEV_TIMER_CTRL, TIM_STOP);
+		sky2_write8(hw, STAT_LEV_TIMER_CTRL, TIM_START);
+	}
+
 	hwidx = sky2_read16(hw, STAT_PUT_IDX);
 	BUG_ON(hwidx >= STATUS_RING_SIZE);
 	rmb();