From 704d33e7006f20f9b4fa7d24a0f08c4b5919b131 Mon Sep 17 00:00:00 2001 From: Florian Fainelli Date: Tue, 28 Oct 2014 11:12:01 -0700 Subject: [PATCH] net: systemport: reset UniMAC coming out of a suspend cycle bcm_sysport_resume() was missing an UniMAC reset which can lead to various receive FIFO corruptions coming out of a suspend cycle. If the RX FIFO is stuck, it will deliver corrupted/duplicate packets towards the host CPU interface. This could be reproduced on crowded network and when Wake-on-LAN is enabled for this particular interface because the switch still forwards packets towards the host CPU interface (SYSTEMPORT), and we had to leave the UniMAC RX enable bit on to allow matching MagicPackets. Once we re-enter the resume function, there is a small window during which the UniMAC receive is still enabled, and we start queueing packets, but the RDMA and RBUF engines are not ready, which leads to having packets stuck in the UniMAC RX FIFO, ultimately delivered towards the host CPU as corrupted. Fixes: 40755a0fce17 ("net: systemport: add suspend and resume support") Signed-off-by: Florian Fainelli Signed-off-by: David S. Miller --- drivers/net/ethernet/broadcom/bcmsysport.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/ethernet/broadcom/bcmsysport.c b/drivers/net/ethernet/broadcom/bcmsysport.c index 7dce91189e51..3a6778a667f4 100644 --- a/drivers/net/ethernet/broadcom/bcmsysport.c +++ b/drivers/net/ethernet/broadcom/bcmsysport.c @@ -1858,6 +1858,8 @@ static int bcm_sysport_resume(struct device *d) if (!netif_running(dev)) return 0; + umac_reset(priv); + /* We may have been suspended and never received a WOL event that * would turn off MPD detection, take care of that now */ -- 2.39.5