From: Ivan Vecera <ivecera@redhat.com>
Date: Fri, 23 Oct 2009 16:53:19 +0200
Subject: [net] forcedeth: let phy power down when IF is down
Message-id: 1256309599-18631-1-git-send-email-ivecera@redhat.com
O-Subject: [RHEL5.5 PATCH] forcedeth: optionally power down phy when interface is down
Bugzilla: 513692
RH-Acked-by: Chuck Ebbert <cebbert@redhat.com>
RH-Acked-by: Prarit Bhargava <prarit@redhat.com>

BZs:
#513692 - ifdown on nVidia CK804 (rev f3) NIC doesn't work

Description:
When the forcedeth based NIC is switched down, the IP address is deassigned
from the interface, but the link is up. If the interface was current active
in the bond then it remains active and the connectivity via this bond
interface is lost.
This patch brings the physical link down when the interface is down by
placing the phy in power-down state, unless WOL is enabled. This
functionality has to be enabled by phy_power_down module parameter because
the power state persists across reboots and some OS, BIOSes and older
versions of Linux don't bother to power up the phy again.

Test:
Tested by customer and by myself.

Upstream commits:
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=cb52deba12f27af90a46d2f8667a64888118a888
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=35a7433c789ba6df6d96b70fa745ae9e6cac0038
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=5a9a8e32ebe269c71d8d3e78f9435fe7729f38e9

Signed-off-by: Ivan Vecera <ivecera@redhat.com>

diff --git a/drivers/net/forcedeth.c b/drivers/net/forcedeth.c
index f3eb92c..56748b6 100644
--- a/drivers/net/forcedeth.c
+++ b/drivers/net/forcedeth.c
@@ -878,6 +878,12 @@ enum {
 };
 static int phy_cross = NV_CROSSOVER_DETECTION_DISABLED;
 
+/*
+ * Power down phy when interface is down (persists through reboot;
+ * older Linux and other OSes may not power it up again)
+ */
+static int phy_power_down = 0;
+
 static inline struct fe_priv *get_nvpriv(struct net_device *dev)
 {
 	return netdev_priv(dev);
@@ -1446,9 +1452,12 @@ static int phy_init(struct net_device *dev)
 	/* some phys clear out pause advertisment on reset, set it back */
 	mii_rw(dev, np->phyaddr, MII_ADVERTISE, reg);
 
-	/* restart auto negotiation */
+	/* restart auto negotiation, power down phy */
 	mii_control = mii_rw(dev, np->phyaddr, MII_BMCR, MII_READ);
 	mii_control |= (BMCR_ANRESTART | BMCR_ANENABLE);
+	if (phy_power_down) {
+		mii_control |= BMCR_PDOWN;
+	}
 	if (mii_rw(dev, np->phyaddr, MII_BMCR, mii_control)) {
 		return PHY_ERROR;
 	}
@@ -5421,9 +5430,13 @@ static int nv_close(struct net_device *dev)
 
 	nv_drain_rxtx(dev);
 
-	if (np->wolenabled) {
+	if (np->wolenabled || !phy_power_down) {
 		writel(NVREG_PFF_ALWAYS|NVREG_PFF_MYADDR, base + NvRegPacketFilterFlags);
 		nv_start_rx(dev);
+	} else {
+		/* power down phy */
+		mii_rw(dev, np->phyaddr, MII_BMCR,
+		       mii_rw(dev, np->phyaddr, MII_BMCR, MII_READ)|BMCR_PDOWN);
 	}
 
 	/* FIXME: power down nic */
@@ -5988,6 +6001,9 @@ static int nv_resume(struct pci_dev *pdev)
 	for (i = 0;i <= np->register_size/sizeof(u32); i++)
 		writel(np->saved_config_space[i], base+i*sizeof(u32));
 
+	/* restore phy state, including autoneg */
+	phy_init(dev);
+
 	netif_device_attach(dev);
 	if (netif_running(dev)) {
 		rc = nv_open(dev);
@@ -6213,6 +6229,8 @@ module_param(dma_64bit, int, 0);
 MODULE_PARM_DESC(dma_64bit, "High DMA is enabled by setting to 1 and disabled by setting to 0.");
 module_param(phy_cross, int, 0);
 MODULE_PARM_DESC(phy_cross, "Phy crossover detection for Realtek 8201 phy is enabled by setting to 1 and disabled by setting to 0.");
+module_param(phy_power_down, int, 0);
+MODULE_PARM_DESC(phy_power_down, "Power down phy and disable link when interface is down (1), or leave phy powered up (0).");
 
 MODULE_AUTHOR("Manfred Spraul <manfred@colorfullife.com>");
 MODULE_DESCRIPTION("Reverse Engineered nForce ethernet driver"