[PATCH v2 net-next 2/3] Revert "net: ethernet: bcmgenet: use phydev from struct net_device"

From: Philippe Reynes
Date: Sun Sep 25 2016 - 12:30:00 EST


From: Florian Fainelli <f.fainelli@xxxxxxxxx>

This reverts commit 62469c76007e ("net: ethernet: bcmgenet: use phydev
from struct net_device") because it causes GENETv1/2/3 adapters to
expose the following behavior after an ifconfig down/up sequence:

PING fainelli-linux (10.112.156.244): 56 data bytes
64 bytes from 10.112.156.244: seq=1 ttl=61 time=1.352 ms
64 bytes from 10.112.156.244: seq=1 ttl=61 time=1.472 ms (DUP!)
64 bytes from 10.112.156.244: seq=1 ttl=61 time=1.496 ms (DUP!)
64 bytes from 10.112.156.244: seq=1 ttl=61 time=1.517 ms (DUP!)
64 bytes from 10.112.156.244: seq=1 ttl=61 time=1.536 ms (DUP!)
64 bytes from 10.112.156.244: seq=1 ttl=61 time=1.557 ms (DUP!)
64 bytes from 10.112.156.244: seq=1 ttl=61 time=752.448 ms (DUP!)

This was previously fixed by commit 5dbebbb44a6a ("net: bcmgenet:
Software reset EPHY after power on") but the commit we are reverting was
essentially making this previous commit void, here is why.

Without commit 62469c76007e we would have the following scenario after
an ifconfig down then up sequence:

- bcmgenet_open() calls bcmgenet_power_up() to make sure the PHY is
initialized *before* we get to initialize the UniMAC, this is
critical to ensure the PHY is in a correct state, priv->phydev is
valid, this code executes fine

- second time from bcmgenet_mii_probe(), through the normal
phy_init_hw() call (which arguably could be optimized out)

Everything is fine in that case. With commit 62469c76007e, we would have
the following scenario to happen after an ifconfig down then up
sequence:

- bcmgenet_close() calls phy_disonnect() which makes dev->phydev become
NULL

- when bcmgenet_open() executes again and calls bcmgenet_mii_reset() from
bcmgenet_power_up() to initialize the internal PHY, the NULL check
becomes true, so we do not reset the PHY, yet we keep going on and
initialize the UniMAC, causing MAC activity to occur

- we call bcmgenet_mii_reset() from bcmgenet_mii_probe(), but this is
too late, the PHY is botched, and causes the above bogus pings/packets
transmission/reception to occur

Reported-by: Jaedon Shin <jaedon.shin@xxxxxxxxx>
Signed-off-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
Signed-off-by: Philippe Reynes <tremyfr@xxxxxxxxx>
---
drivers/net/ethernet/broadcom/genet/bcmgenet.c | 45 +++++++++++++----------
drivers/net/ethernet/broadcom/genet/bcmgenet.h | 1 +
drivers/net/ethernet/broadcom/genet/bcmmii.c | 24 +++++++------
3 files changed, 39 insertions(+), 31 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.c b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
index 46f9043..47d0a2b 100644
--- a/drivers/net/ethernet/broadcom/genet/bcmgenet.c
+++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
@@ -453,25 +453,29 @@ static inline void bcmgenet_rdma_ring_writel(struct bcmgenet_priv *priv,
static int bcmgenet_get_settings(struct net_device *dev,
struct ethtool_cmd *cmd)
{
+ struct bcmgenet_priv *priv = netdev_priv(dev);
+
if (!netif_running(dev))
return -EINVAL;

- if (!dev->phydev)
+ if (!priv->phydev)
return -ENODEV;

- return phy_ethtool_gset(dev->phydev, cmd);
+ return phy_ethtool_gset(priv->phydev, cmd);
}

static int bcmgenet_set_settings(struct net_device *dev,
struct ethtool_cmd *cmd)
{
+ struct bcmgenet_priv *priv = netdev_priv(dev);
+
if (!netif_running(dev))
return -EINVAL;

- if (!dev->phydev)
+ if (!priv->phydev)
return -ENODEV;

- return phy_ethtool_sset(dev->phydev, cmd);
+ return phy_ethtool_sset(priv->phydev, cmd);
}

static int bcmgenet_set_rx_csum(struct net_device *dev,
@@ -937,7 +941,7 @@ static int bcmgenet_get_eee(struct net_device *dev, struct ethtool_eee *e)
e->eee_active = p->eee_active;
e->tx_lpi_timer = bcmgenet_umac_readl(priv, UMAC_EEE_LPI_TIMER);

- return phy_ethtool_get_eee(dev->phydev, e);
+ return phy_ethtool_get_eee(priv->phydev, e);
}

static int bcmgenet_set_eee(struct net_device *dev, struct ethtool_eee *e)
@@ -954,7 +958,7 @@ static int bcmgenet_set_eee(struct net_device *dev, struct ethtool_eee *e)
if (!p->eee_enabled) {
bcmgenet_eee_enable_set(dev, false);
} else {
- ret = phy_init_eee(dev->phydev, 0);
+ ret = phy_init_eee(priv->phydev, 0);
if (ret) {
netif_err(priv, hw, dev, "EEE initialization failed\n");
return ret;
@@ -964,12 +968,14 @@ static int bcmgenet_set_eee(struct net_device *dev, struct ethtool_eee *e)
bcmgenet_eee_enable_set(dev, true);
}

- return phy_ethtool_set_eee(dev->phydev, e);
+ return phy_ethtool_set_eee(priv->phydev, e);
}

static int bcmgenet_nway_reset(struct net_device *dev)
{
- return genphy_restart_aneg(dev->phydev);
+ struct bcmgenet_priv *priv = netdev_priv(dev);
+
+ return genphy_restart_aneg(priv->phydev);
}

/* standard ethtool support functions. */
@@ -996,13 +1002,12 @@ static const struct ethtool_ops bcmgenet_ethtool_ops = {
static int bcmgenet_power_down(struct bcmgenet_priv *priv,
enum bcmgenet_power_mode mode)
{
- struct net_device *ndev = priv->dev;
int ret = 0;
u32 reg;

switch (mode) {
case GENET_POWER_CABLE_SENSE:
- phy_detach(ndev->phydev);
+ phy_detach(priv->phydev);
break;

case GENET_POWER_WOL_MAGIC:
@@ -1063,6 +1068,7 @@ static void bcmgenet_power_up(struct bcmgenet_priv *priv,
/* ioctl handle special commands that are not present in ethtool. */
static int bcmgenet_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
{
+ struct bcmgenet_priv *priv = netdev_priv(dev);
int val = 0;

if (!netif_running(dev))
@@ -1072,10 +1078,10 @@ static int bcmgenet_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
case SIOCGMIIPHY:
case SIOCGMIIREG:
case SIOCSMIIREG:
- if (!dev->phydev)
+ if (!priv->phydev)
val = -ENODEV;
else
- val = phy_mii_ioctl(dev->phydev, rq, cmd);
+ val = phy_mii_ioctl(priv->phydev, rq, cmd);
break;

default:
@@ -2458,7 +2464,6 @@ static void bcmgenet_irq_task(struct work_struct *work)
{
struct bcmgenet_priv *priv = container_of(
work, struct bcmgenet_priv, bcmgenet_irq_work);
- struct net_device *ndev = priv->dev;

netif_dbg(priv, intr, priv->dev, "%s\n", __func__);

@@ -2471,7 +2476,7 @@ static void bcmgenet_irq_task(struct work_struct *work)

/* Link UP/DOWN event */
if (priv->irq0_stat & UMAC_IRQ_LINK_EVENT) {
- phy_mac_interrupt(ndev->phydev,
+ phy_mac_interrupt(priv->phydev,
!!(priv->irq0_stat & UMAC_IRQ_LINK_UP));
priv->irq0_stat &= ~UMAC_IRQ_LINK_EVENT;
}
@@ -2833,7 +2838,7 @@ static void bcmgenet_netif_start(struct net_device *dev)
/* Monitor link interrupts now */
bcmgenet_link_intr_enable(priv);

- phy_start(dev->phydev);
+ phy_start(priv->phydev);
}

static int bcmgenet_open(struct net_device *dev)
@@ -2932,7 +2937,7 @@ static void bcmgenet_netif_stop(struct net_device *dev)
struct bcmgenet_priv *priv = netdev_priv(dev);

netif_tx_stop_all_queues(dev);
- phy_stop(dev->phydev);
+ phy_stop(priv->phydev);
bcmgenet_intr_disable(priv);
bcmgenet_disable_rx_napi(priv);
bcmgenet_disable_tx_napi(priv);
@@ -2958,7 +2963,7 @@ static int bcmgenet_close(struct net_device *dev)
bcmgenet_netif_stop(dev);

/* Really kill the PHY state machine and disconnect from it */
- phy_disconnect(dev->phydev);
+ phy_disconnect(priv->phydev);

/* Disable MAC receive */
umac_enable_set(priv, CMD_RX_EN, false);
@@ -3517,7 +3522,7 @@ static int bcmgenet_suspend(struct device *d)

bcmgenet_netif_stop(dev);

- phy_suspend(dev->phydev);
+ phy_suspend(priv->phydev);

netif_device_detach(dev);

@@ -3581,7 +3586,7 @@ static int bcmgenet_resume(struct device *d)
if (priv->wolopts)
clk_disable_unprepare(priv->clk_wol);

- phy_init_hw(dev->phydev);
+ phy_init_hw(priv->phydev);
/* Speed settings must be restored */
bcmgenet_mii_config(priv->dev);

@@ -3614,7 +3619,7 @@ static int bcmgenet_resume(struct device *d)

netif_device_attach(dev);

- phy_resume(dev->phydev);
+ phy_resume(priv->phydev);

if (priv->eee.eee_enabled)
bcmgenet_eee_enable_set(dev, true);
diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.h b/drivers/net/ethernet/broadcom/genet/bcmgenet.h
index 0f0868c..1e2dc34 100644
--- a/drivers/net/ethernet/broadcom/genet/bcmgenet.h
+++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.h
@@ -597,6 +597,7 @@ struct bcmgenet_priv {

/* MDIO bus variables */
wait_queue_head_t wq;
+ struct phy_device *phydev;
bool internal_phy;
struct device_node *phy_dn;
struct device_node *mdio_dn;
diff --git a/drivers/net/ethernet/broadcom/genet/bcmmii.c b/drivers/net/ethernet/broadcom/genet/bcmmii.c
index e907acd..457c3bc 100644
--- a/drivers/net/ethernet/broadcom/genet/bcmmii.c
+++ b/drivers/net/ethernet/broadcom/genet/bcmmii.c
@@ -86,7 +86,7 @@ static int bcmgenet_mii_write(struct mii_bus *bus, int phy_id,
void bcmgenet_mii_setup(struct net_device *dev)
{
struct bcmgenet_priv *priv = netdev_priv(dev);
- struct phy_device *phydev = dev->phydev;
+ struct phy_device *phydev = priv->phydev;
u32 reg, cmd_bits = 0;
bool status_changed = false;

@@ -183,9 +183,9 @@ void bcmgenet_mii_reset(struct net_device *dev)
if (GENET_IS_V4(priv))
return;

- if (dev->phydev) {
- phy_init_hw(dev->phydev);
- phy_start_aneg(dev->phydev);
+ if (priv->phydev) {
+ phy_init_hw(priv->phydev);
+ phy_start_aneg(priv->phydev);
}
}

@@ -236,7 +236,6 @@ static void bcmgenet_internal_phy_setup(struct net_device *dev)

static void bcmgenet_moca_phy_setup(struct bcmgenet_priv *priv)
{
- struct net_device *ndev = priv->dev;
u32 reg;

/* Speed settings are set in bcmgenet_mii_setup() */
@@ -245,14 +244,14 @@ static void bcmgenet_moca_phy_setup(struct bcmgenet_priv *priv)
bcmgenet_sys_writel(priv, reg, SYS_PORT_CTRL);

if (priv->hw_params->flags & GENET_HAS_MOCA_LINK_DET)
- fixed_phy_set_link_update(ndev->phydev,
+ fixed_phy_set_link_update(priv->phydev,
bcmgenet_fixed_phy_link_update);
}

int bcmgenet_mii_config(struct net_device *dev)
{
struct bcmgenet_priv *priv = netdev_priv(dev);
- struct phy_device *phydev = dev->phydev;
+ struct phy_device *phydev = priv->phydev;
struct device *kdev = &priv->pdev->dev;
const char *phy_name = NULL;
u32 id_mode_dis = 0;
@@ -303,7 +302,7 @@ int bcmgenet_mii_config(struct net_device *dev)
* capabilities, use that knowledge to also configure the
* Reverse MII interface correctly.
*/
- if ((phydev->supported & PHY_BASIC_FEATURES) ==
+ if ((priv->phydev->supported & PHY_BASIC_FEATURES) ==
PHY_BASIC_FEATURES)
port_ctrl = PORT_MODE_EXT_RVMII_25;
else
@@ -372,7 +371,7 @@ int bcmgenet_mii_probe(struct net_device *dev)
return -ENODEV;
}
} else {
- phydev = dev->phydev;
+ phydev = priv->phydev;
phydev->dev_flags = phy_flags;

ret = phy_connect_direct(dev, phydev, bcmgenet_mii_setup,
@@ -383,6 +382,8 @@ int bcmgenet_mii_probe(struct net_device *dev)
}
}

+ priv->phydev = phydev;
+
/* Configure port multiplexer based on what the probed PHY device since
* reading the 'max-speed' property determines the maximum supported
* PHY speed which is needed for bcmgenet_mii_config() to configure
@@ -390,7 +391,7 @@ int bcmgenet_mii_probe(struct net_device *dev)
*/
ret = bcmgenet_mii_config(dev);
if (ret) {
- phy_disconnect(phydev);
+ phy_disconnect(priv->phydev);
return ret;
}

@@ -400,7 +401,7 @@ int bcmgenet_mii_probe(struct net_device *dev)
* Ethernet MAC ISRs
*/
if (priv->internal_phy)
- phydev->irq = PHY_IGNORE_INTERRUPT;
+ priv->phydev->irq = PHY_IGNORE_INTERRUPT;

return 0;
}
@@ -605,6 +606,7 @@ static int bcmgenet_mii_pd_init(struct bcmgenet_priv *priv)

}

+ priv->phydev = phydev;
priv->phy_interface = pd->phy_interface;

return 0;
--
1.7.4.4