From mboxrd@z Thu Jan  1 00:00:00 1970
From: Shawn Guo <shawn.guo@freescale.com>
Subject: FEC driver hangs hardware on i.MX6SX
Date: Sun, 20 Jul 2014 10:57:33 +0800
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Cc: Frank Li <Frank.li@freescale.com>,
	"David S. Miller" <davem@davemloft.net>,
	Shawn Guo <shawn.guo@freescale.com>, <netdev@vger.kernel.org>,
	<linux-arm-kernel@lists.infradead.org>
To: Fugang Duan <B38611@freescale.com>
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Hi Fugang,

Your commit e8fcfcd5684a (net: fec: optimize the clock management to
save power) landed on mainline with v3.16-rc1.  It causes a hardware
hang on i.MX6SX, if the rootfs is not on NFS but something else like
MMC.

I think the cause is that PTP is still accessing registers after FEC
driver calls fec_enet_clk_enable(ndev, false) to disable FEC clocks.
Can you please try to provide a fix for this regression soon?

Shawn