kernel/drivers/net/ethernet/freescale/fec_main.c, branch linux-4.3.y

net: fec: add netif status check before set mac address

2015-09-10T03:30:10Z

There exist one issue by below case that case system hang: ifconfig eth0 down ifconfig eth0 hw ether 00:10:19:19:81:19 After eth0 down, all fec clocks are gated off. In the .fec_set_mac_address() function, it will set new MAC address to registers, which causes system hang. So it needs to add netif status check to avoid registers access when clocks are gated off. Until eth0 up the new MAC address are wrote into related registers. V2: As Lucas Stach's suggestion, add a comment in the code to explain why it needed. CC: Lucas Stach CC: Florian Fainelli Signed-off-by: Fugang Duan Signed-off-by: David S. Miller

net: fec: normalize return value of pm_runtime_get_sync() in MDIO write

2015-09-06T05:04:06Z

If fec MDIO write method succeeds its return value comes from call to pm_runtime_get_sync(). But pm_runtime_get_sync() can also return 1. In case of Micrel KSZ9031 PHY this value will then be returned along the call chain of phy_write() -> ksz9031_extended_write() -> ksz9031_center_flp_timing() -> ksz9031_config_init() -> phy_init_hw() -> phy_attach_direct() -> phy_connect_direct(). Then phy_connect() will cast it into a pointer using ERR_PTR(), which then fec_enet_mii_probe() will try to dereference resulting in an oops. Fix it by normalizing return value of pm_runtime_get_sync() to be zero if positive in MDIO write method. Fixes: 8fff755e9f8d ("net: fec: Ensure clocks are enabled while using mdio bus") Signed-off-by: Maciej Szmigiero Acked-by: Andrew Lunn Signed-off-by: David S. Miller

net: fec: clear receive interrupts before processing a packet

2015-09-02T23:06:04Z

The patch just to re-submit the patch "db3421c114cfa6326" because the patch "4d494cdc92b3b9a0" remove the change. Clear any pending receive interrupt before we process a pending packet. This helps to avoid any spurious interrupts being raised after we have fully cleaned the receive ring, while still allowing an interrupt to be raised if we receive another packet. The position of this is critical: we must do this prior to reading the next packet status to avoid potentially dropping an interrupt when a packet is still pending. Acked-by: Fugang Duan Signed-off-by: Russell King Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2015-08-28T04:45:31Z

net: fec: use reinit_completion() in mdio accessor functions

2015-08-25T23:33:16Z

Rather than re-initialising the entire completion on every mdio access, use reinit_completion() which only resets the completion count. This avoids possible reinitialisation of the contained spinlock and waitqueue while they may be in use (eg, mid-completion.) Such an event could occur if there's a long delay in interrupt handling causing the mdio accessor to time out, then a second access comes in while the interrupt handler on a different CPU has called complete(). Another scenario where this has been observed is while locking has been missing at the phy layer, allowing concurrent attempts to access the MDIO bus. Signed-off-by: Russell King Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2015-08-13T23:23:11Z

Conflicts: drivers/net/ethernet/cavium/Kconfig The cavium conflict was overlapping dependency changes. Signed-off-by: David S. Miller

net: fec: Remove unneeded use of IS_ERR_VALUE() macro

2015-08-12T23:45:46Z

There is no need to use the IS_ERR_VALUE() macro for checking the return value from pm_runtime_* functions. Just do a simple negative test instead. The semantic patch that makes this change is available in scripts/coccinelle/api/pm_runtime.cocci. Signed-off-by: Fabio Estevam Signed-off-by: David S. Miller

net: fec: fix the race between xmit and bdp reclaiming path

2015-08-10T20:28:14Z

When we transmit a fragmented skb, we may run into a race like the following scenario (assume txq->cur_tx is next to txq->dirty_tx): cpu 0 cpu 1 fec_enet_txq_submit_skb reserve a bdp for the first fragment fec_enet_txq_submit_frag_skb update the bdp for the other fragment update txq->cur_tx fec_enet_tx_queue bdp = fec_enet_get_nextdesc(txq->dirty_tx, fep, queue_id); This bdp is the bdp reserved for the first segment. Given that this bdp BD_ENET_TX_READY bit is not set and txq->cur_tx is already pointed to a bdp beyond this one. We think this is a completed bdp and try to reclaim it. update the bdp for the first segment update txq->cur_tx So we shouldn't update the txq->cur_tx until all the update to the bdps used for fragments are performed. Also add the corresponding memory barrier to guarantee that the update to the bdps, dirty_tx and cur_tx performed in the proper order. Signed-off-by: Kevin Hao Signed-off-by: David S. Miller

net: fec: fix initial runtime PM refcount

2015-08-07T01:53:25Z

The clocks are initially active and thus the device is marked active. This still keeps the PM refcount at 0, the pm_runtime_put_autosuspend() call at the end of probe then leaves us with an invalid refcount of -1, which in turn leads to the device staying in suspended state even though netdev open had been called. Fix this by initializing the refcount to be coherent with the initial device status. Fixes: 8fff755e9f8 (net: fec: Ensure clocks are enabled while using mdio bus) Signed-off-by: Lucas Stach Tested-by: Uwe Kleine-König Signed-off-by: David S. Miller

net: fec: Ensure clocks are enabled while using mdio bus

2015-07-27T08:21:47Z

When a switch is attached to the mdio bus, the mdio bus can be used while the interface is not open. If the IPG clock is not enabled, MDIO reads/writes will simply time out. Add support for runtime PM to control this clock. Enable/disable this clock using runtime PM, with open()/close() and mdio read()/write() function triggering runtime PM operations. Since PM is optional, the IPG clock is enabled at probe and is no longer modified by fec_enet_clk_enable(), thus if PM is not enabled in the kernel, it is guaranteed the clock is running when MDIO operations are performed. Signed-off-by: Andrew Lunn Signed-off-by: Lucas Stach Cc: tyler.baker@linaro.org Cc: fabio.estevam@freescale.com Cc: shawn.guo@linaro.org Tested-by: Fabio Estevam Tested-by: Tyler Baker Signed-off-by: David S. Miller