If skb allocation for the rx ring fails repeatedly, we can reach a point
were the ring is empty. In this condition, the driver is out of sync with
the h/w. While this has always been possible, the removal of the skb
recycling seems to have made triggering this problem easier.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The xgmac driver assumes 1 frame per descriptor. If a frame larger than
the descriptor's buffer size is received, the frame will spill over into
the next descriptor. So check for received frames that span more than one
descriptor and discard them. This prevents a crash if we receive erroneous
large packets.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

NET_ADDR_SET is set in dev_set_mac_address() no need to alter
dev->addr_assign_type value in drivers.
Signed-off-by: NJiri Pirko <jiri@resnulli.us>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

On gcc 4.7, we will get alignment traps in the ip stack if we don't align
the ip headers on receive. The h/w can support this, so use ip aligned
allocations.

Cut down the unnecessary padding on the allocation. The buffer can start on
any byte alignment, but the size including the begining offset must be 8
byte aligned. So the h/w buffer size must include the NET_IP_ALIGN offset.

Thanks to Eric Dumazet for the initial patch highlighting the padding issues.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Acked-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Only generate tx interrupts on every ring size / 4 descriptors. Move the
netif_stop_queue call to the end of the xmit function rather than
checking at the beginning.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The interrupts have already been cleared, so we don't need to clear them
again. Also, we could miss interrupts if they are cleared, but we don't
process the packet.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The standard readl/writel accessors involve a spinlock and cache sync
operation on ARM platforms with an outer cache. Only DMA triggering
accesses need this, so use the raw variants instead in the critical paths.

The relaxed variants would be more appropriate, but don't exist on all
arches.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

New received frames will trigger the rx DMA to poll the DMA descriptors,
so there is no need to tell the h/w to poll. We also want to enable
dropping frames from the fifo when there is no buffer.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Enable the tx dma to start reading the next frame while sending the current
frame.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Over time, skb recycling infrastructure got litle interest and
many bugs. Generic rx path skb allocation is now using page
fragments for efficient GRO / TCP coalescing, and recyling
a tx skb for rx path is not worth the pain.

Last identified bug is that fat skbs can be recycled
and it can endup using high order pages after few iterations.

With help from Maxime Bizon, who pointed out that commit
87151b86 (net: allow pskb_expand_head() to get maximum tailroom)
introduced this regression for recycled skbs.

Instead of fixing this bug, lets remove skb recycling.

Drivers wanting really hot skbs should use build_skb() anyway,
to allocate/populate sk_buff right before netif_receive_skb()
Signed-off-by: NEric Dumazet <edumazet@google.com>
Cc: Maxime Bizon <mbizon@freebox.fr>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Enabling RX cut-thru mode yields better performance as received frames
start getting written to memory before a whole frame is received.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Increase the number of outstanding read and write AXI transactions from 1
to 8 for better performance.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix intermittent hangs in xgmac_rx_refill. If a ring buffer entry already
had an skb allocated, then xgmac_rx_refill would get stuck in a loop. This
can happen on a rx error when we just leave the skb allocated to the entry.

[ 7884.510000] INFO: rcu_preempt detected stall on CPU 0 (t=727315 jiffies)
[ 7884.510000] [<c0010a59>] (unwind_backtrace+0x1/0x98) from [<c006fd93>] (__rcu_pending+0x11b/0x2c4)
[ 7884.510000] [<c006fd93>] (__rcu_pending+0x11b/0x2c4) from [<c0070b95>] (rcu_check_callbacks+0xed/0x1a8)
[ 7884.510000] [<c0070b95>] (rcu_check_callbacks+0xed/0x1a8) from [<c0036abb>] (update_process_times+0x2b/0x48)
[ 7884.510000] [<c0036abb>] (update_process_times+0x2b/0x48) from [<c004e8fd>] (tick_sched_timer+0x51/0x94)
[ 7884.510000] [<c004e8fd>] (tick_sched_timer+0x51/0x94) from [<c0045527>] (__run_hrtimer+0x4f/0x1e8)
[ 7884.510000] [<c0045527>] (__run_hrtimer+0x4f/0x1e8) from [<c0046003>] (hrtimer_interrupt+0xd7/0x1e4)
[ 7884.510000] [<c0046003>] (hrtimer_interrupt+0xd7/0x1e4) from [<c00101d3>] (twd_handler+0x17/0x24)
[ 7884.510000] [<c00101d3>] (twd_handler+0x17/0x24) from [<c006be39>] (handle_percpu_devid_irq+0x59/0x114)
[ 7884.510000] [<c006be39>] (handle_percpu_devid_irq+0x59/0x114) from [<c0069aab>] (generic_handle_irq+0x17/0x2c)
[ 7884.510000] [<c0069aab>] (generic_handle_irq+0x17/0x2c) from [<c000cc8d>] (handle_IRQ+0x35/0x7c)
[ 7884.510000] [<c000cc8d>] (handle_IRQ+0x35/0x7c) from [<c033b153>] (__irq_svc+0x33/0xb8)
[ 7884.510000] [<c033b153>] (__irq_svc+0x33/0xb8) from [<c0244b06>] (xgmac_rx_refill+0x3a/0x140)
[ 7884.510000] [<c0244b06>] (xgmac_rx_refill+0x3a/0x140) from [<c02458ed>] (xgmac_poll+0x265/0x3bc)
[ 7884.510000] [<c02458ed>] (xgmac_poll+0x265/0x3bc) from [<c029fcbf>] (net_rx_action+0xc3/0x200)
[ 7884.510000] [<c029fcbf>] (net_rx_action+0xc3/0x200) from [<c0030cab>] (__do_softirq+0xa3/0x1bc)
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix net tx watchdog timeout recovery. The descriptor ring was reset,
but the DMA engine was not reset to the beginning of the ring.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use eth_hw_addr_random() instead of calling random_ether_addr()
to set addr_assign_type correctly to NET_ADDR_RANDOM.

Reset the state to NET_ADDR_PERM as soon as the MAC get
changed via .ndo_set_mac_address.

v2: adapt to renamed eth_hw_addr_random()
Signed-off-by: NDanny Kukawka <danny.kukawka@bisect.de>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Make local function static, make ethtool_ops const.
Compile tested only.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add support for the XGMAC 10Gb ethernet device in the Calxeda Highbank
SOC.
Signed-off-by: NRob Herring <rob.herring@calxeda.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>