Since commit 0fd56bb5 ("gianfar:
Add support for skb recycling"), gianfar puts skbuffs that are in
the rx ring back onto the recycle list as-is in case there was a
receive error, but this breaks the following invariant: that all
skbuffs on the recycle list have skb->data = skb->head + NET_SKB_PAD.

The RXBUF_ALIGNMENT realignment done in gfar_new_skb() will be done
twice on skbuffs recycled in this way, causing there not to be enough
room in the skb anymore to receive a full packet, eventually leading
to an skb_over_panic from gfar_clean_rx_ring() -> skb_put().

Resetting the skb->data pointer to skb->head + NET_SKB_PAD before
putting the skb back onto the recycle list restores the mentioned
invariant, and should fix this issue.
Reported-by: NMichael Guntsche <mike@it-loops.com>
Tested-by: NMichael Guntsche <mike@it-loops.com>
Signed-off-by: NLennert Buytenhek <buytenh@wantstofly.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

After a transmit timed out, the reset task will be called, which will free the
allocated resources(stop_gfar). If gfar_poll will be called before the
resources get allocated again gfar_clean_tx_ring will call
dev_kfree_skb_any(NULL).

Example crash:

ops: Kernel access of bad area, sig: 11 [#1]
PREEMPT RSBBA100
Modules linked in:
NIP: c01a10c4 LR: c013b254 CTR: c013c038
REGS: c02e7d20 TRAP: 0300   Not tainted  (2.6.27.20)
MSR: 00001032 <ME,IR,DR>  CR: 24000082  XER: 20000000
DAR: 000000a0, DSISR: 20000000
TASK = c02ce578[0] 'swapper' THREAD: c02e6000
GPR00: 000000a0 c02e7dd0 c02ce578 00000000 00000040 00000001 c02ec1c0 
00001032
GPR08: c080d1e0 df9ea800 00000000 00000000 24000082 ffffffff 0404f000 
00000000
GPR16: ffffffbf ffffffff ffffffff ffdff7ff ffffffff c02d0fd4 00100100 
00200200
GPR24: c031220c 00000001 00000001 00000000 00000000 df849800 ff109000 
df849b80
NIP [c01a10c4] dev_kfree_skb_irq+0x18/0x70
LR [c013b254] gfar_clean_tx_ring+0x70/0x11c
Call Trace:
[c02e7dd0] [c003e978] update_wall_time+0x730/0x744 (unreliable)
[c02e7df0] [c013b254] gfar_clean_tx_ring+0x70/0x11c
[c02e7e10] [c013c07c] gfar_poll+0x44/0x150
[c02e7e30] [c01a064c] net_rx_action+0xa8/0x19c
[c02e7e70] [c00251d4] __do_softirq+0x64/0xc0
[c02e7e90] [c0006384] do_softirq+0x40/0x58
[c02e7ea0] [c00250a8] irq_exit+0x40/0x9c
[c02e7eb0] [c000642c] do_IRQ+0x90/0xac
[c02e7ec0] [c0010ab4] ret_from_except+0x0/0x14
--- Exception: 501 at cpu_idle+0x9c/0xf8
    LR = cpu_idle+0x9c/0xf8
[c02e7f80] [c0009820] cpu_idle+0x58/0xf8 (unreliable)
[c02e7fa0] [c01fb8c8] __got2_end+0x7c/0x90
[c02e7fc0] [c026c794] start_kernel+0x2c0/0x2d4
[c02e7ff0] [00003438] 0x3438
Instruction dump:
7fa00124 80010024 bba10014 38210020 7c0803a6 4e800020 9421ffe0 7c0802a6
7c6b1b78 90010024 380300a0 bfa10014 <7d200028> 3129ffff 7d20012d 40a2fff4
Kernel panic - not syncing: Fatal exception in interrupt

This Patch calls netif_stop_queue before calling stop_gfar.
Signed-off-by: NMarkus Brunner <super.firetwister@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We can't put 'mdio' until after we've used it in the
fsl_pq_mdio_bus_name() call.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NLi Yang <leoli@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Noticed by Li Yang.
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The code that was added to increase headroom was wrong.
It doesn't handle the case where gfar_add_fcb() changes the skb.
Better to do check at start of transmit (outside of lock), where
error handling is better anyway.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Gianfar uses a hardware header FCB for offloading.  However when used
with bridging or IP forwarding, TX skb might not have enough headroom
for the FCB.  Reallocate skb for such cases.
Signed-off-by: NLi Yang <leoli@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit 4826857f ("gianfar: pass the
proper dev to DMA ops") introduced this build breakage:

  CC      drivers/net/gianfar.o
drivers/net/gianfar.c: In function 'gfar_suspend':
drivers/net/gianfar.c:552: error: 'struct gfar_private' has no member named 'dev'
drivers/net/gianfar.c: In function 'gfar_resume':
drivers/net/gianfar.c:601: error: 'struct gfar_private' has no member named 'dev'
make[2]: *** [drivers/net/gianfar.o] Error 1

Fix this by converting suspend and resume routines to use
gfar_private->ndev.
Signed-off-by: NAnton Vorontsov <avorontsov@ru.mvista.com>
Acked-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We need to be passing the of_platform device struct into the DMA ops as
its the one that has the archdata setup to know which low-level DMA ops we
should be using (not the net_device one).  This isn't an issue until we
expect the archdata to be setup correctly.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NAndy Fleming <afleming@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fixes a wrong check on num_txbdfree. It could lead to
num_txbdfree become nagative.  Result was that the gianfar stops
sending data.

Changes from first version :
- removed a space between parens (David Millers comment)
- full email address in signed off line
Signed-off-by: NRini van Zetten <rini@arvoo.nl>
Acked-by: NAndy Fleming <afleming@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Ira Snyder found that commit 8c7396ae
"gianfar: Merge Tx and Rx interrupt for scheduling clean up ring" can
cause hangs. It's because there was removed clearing of interrupts in
gfar_schedule_cleanup() (which is called by an interrupt handler) in
case when netif scheduling has been disabled. This patch brings back
this action and a comment.
Reported-by: NIra Snyder <iws@ovro.caltech.edu>
Reported-by: NPeter Korsgaard <jacmet@sunsite.dk>
Bisected-by: NIra Snyder <iws@ovro.caltech.edu>
Tested-by: NPeter Korsgaard <jacmet@sunsite.dk>
Tested-by: NIra Snyder <iws@ovro.caltech.edu>
Signed-off-by: NJarek Poplawski <jarkao2@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Stashing is only supported on the 85xx (e500-based) SoCs.  The 83xx and 86xx
chips don't have a proper cache for this.  U-Boot has been updated to add
stashing properties to the device tree nodes of gianfar devices on 85xx.  So
now we modify Linux to keep stashing off unless those properties are there.
Signed-off-by: NAndy Fleming <afleming@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Signed-off-by: NAndy Fleming <afleming@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The MDIO bus drivers for the UCC and gianfar ethernet controllers are
essentially the same.  There's no reason to duplicate that much code.
Signed-off-by: NAndy Fleming <afleming@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

SOFT_RESET must be asserted for at least 3 TX clocks in order for it to work
properly.  The syncs in the gfar_write() commands have been hiding this, but
we need to guarantee it.
Signed-off-by: NAndy Fleming <afleming@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fixes following sparse warnings:

  CHECK   gianfar_ethtool.c
gianfar_ethtool.c:610:26: warning: symbol 'gfar_ethtool_ops' was not declared. Should it be static?
  CHECK   gianfar_mii.c
gianfar_mii.c:108:35: warning: cast adds address space to expression (<asn:2>)
gianfar_mii.c:119:35: warning: cast adds address space to expression (<asn:2>)
gianfar_mii.c:128:35: warning: cast adds address space to expression (<asn:2>)
gianfar_mii.c:272:5: warning: cast removes address space of expression
gianfar_mii.c:271:15: warning: cast adds address space to expression (<asn:2>)
gianfar_mii.c:340:11: warning: cast adds address space to expression (<asn:2>)
  CHECK   gianfar_sysfs.c
gianfar_sysfs.c:84:1: warning: symbol 'dev_attr_bd_stash' was not declared. Should it be static?
gianfar_sysfs.c:133:1: warning: symbol 'dev_attr_rx_stash_size' was not declared. Should it be static?
gianfar_sysfs.c:175:1: warning: symbol 'dev_attr_rx_stash_index' was not declared. Should it be static?
gianfar_sysfs.c:213:1: warning: symbol 'dev_attr_fifo_threshold' was not declared. Should it be static?
gianfar_sysfs.c:250:1: warning: symbol 'dev_attr_fifo_starve' was not declared. Should it be static?
gianfar_sysfs.c:287:1: warning: symbol 'dev_attr_fifo_starve_off' was not declared. Should it be static?
Signed-off-by: NAnton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch implements wakeup management for the gianfar driver.

The driver should set wakeup enable if WOL is enabled, so that
phylib won't power off an attached PHY.
Signed-off-by: NAnton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

commit 77ecaf2d ("gianfar: Fix VLAN
HW feature related frame/buffer size calculation") wrongly removed
priv->vlgrp assignment, and now priv->vlgrp is always NULL.

This patch fixes the issue, plus fixes following sparse warning
introduced by the same commit:
gianfar.c:1406:13: warning: context imbalance in 'gfar_vlan_rx_register' - wrong count at exit

gfar_vlan_rx_register() checks for "if (old_grp == grp)" and tries
to return w/o dropping the lock.

According to net/8021q/vlan.c VLAN core issues rx_register() callback:
1. In register_vlan_dev() only on a newly created group;
2. In unregister_vlan_dev() only if the group becomes empty.

Thus the check in the gianfar driver isn't needed.
Signed-off-by: NAnton Vorontsov <avorontsov@ru.mvista.com>
Acked-by: NAndy Fleming <afleming@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Following the removal of the unused struct net_device * parameter from
the NAPI functions named *netif_rx_* in commit 908a7a16, they are
exactly equivalent to the corresponding *napi_* functions and are
therefore redundant.
Signed-off-by: NBen Hutchings <bhutchings@solarflare.com>
Acked-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch fixes following bug:

BUG: soft lockup - CPU#0 stuck for 61s! [S03mountvirtfs-:922]
Modules linked in:
NIP: c006505c LR: c00675f0 CTR: c0020438
REGS: c7a1db90 TRAP: 0901   Not tainted  (2.6.28-rc8-01311-g8c7396ae)
MSR: 00009032 <EE,ME,IR,DR>  CR: 28248442  XER: 20000000
TASK = c7a288a0[922] 'S03mountvirtfs-' THREAD: c7a1c000
GPR00: 00009032 c7a1dc40 c7a288a0 00000024 c79a1840 00000000 00000300 00000020
GPR08: c035f97c 00000000 00004008 c04d5210 00000000
NIP [c006505c] handle_IRQ_event+0x34/0xb0
LR [c00675f0] handle_level_irq+0xa8/0x144
Call Trace:
[c7a1dc40] [c00204d8] ipic_mask_irq+0xa0/0xb4 (unreliable)
[c7a1dc60] [c00675f0] handle_level_irq+0xa8/0x144
[c7a1dc80] [c00067f8] do_IRQ+0x78/0x108
[c7a1dc90] [c0014d7c] ret_from_except+0x0/0x14
--- Exception: 501 at gfar_schedule_cleanup+0x54/0x7c
    LR = gfar_transmit+0x14/0x28
[c7a1dd50] [c0352a3c] _spin_unlock_irqrestore+0x18/0x30 (unreliable)
[c7a1dd60] [c01f49a8] gfar_transmit+0x14/0x28
[c7a1dd70] [c0065084] handle_IRQ_event+0x5c/0xb0
[c7a1dd90] [c00675f0] handle_level_irq+0xa8/0x144
[c7a1ddb0] [c00067f8] do_IRQ+0x78/0x108
[c7a1ddc0] [c0014d7c] ret_from_except+0x0/0x14
--- Exception: 501 at up_read+0x10/0x48
    LR = do_page_fault+0x2b0/0x3e0
[c7a1de80] [c7a177e8] 0xc7a177e8 (unreliable)
[c7a1de90] [c0017964] do_page_fault+0x2b0/0x3e0
[c7a1df40] [c0014b14] handle_page_fault+0xc/0x80
--- Exception: 301 at 0xfe98b7c
    LR = 0xfe989c0
Instruction dump:
7c0802a6 bf810010 7c9f2378 7c7c1b78 90010024 80040004 70090020 40820010
7c0000a6 60008000 7c000124 3bc00000 <3ba00000> 48000010 83ff0014 2f9f0000


The bug introduced by commit 8c7396ae
("gianfar: Merge Tx and Rx interrupt for scheduling clean up ring").

The commit merged TX and RX interrupt code into a single routine that
schedules NAPI, but no locks were introduced. This causes irq races, so
when irqs are enabled and netif_rx_schedule_prep() returns 0, nobody
disable the interrupts again. This leads to interrupt storm and finally
to the lockup.
Signed-off-by: NAnton Vorontsov <avorontsov@ru.mvista.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is the same kind of wrapper that can also be found in many
other network device drivers.

Tested with a freescale MPC8349E host CPU:
Toggled the interface LEDs on a DP83865 PHY.
Signed-off-by: NClifford Wolf <clifford@clifford.at>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Commit b31a1d8b ("gianfar: Convert
gianfar to an of_platform_driver") went back to using BUS_ID_SIZE
instead of sizeof() as per the larger patch series that will remove
"char bus_id[20]" from struct device.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When changing the link between 100Mbps and 1Gbps in SGMII mode it was
found out that the link would stop working.  The issue is that ECNTRL[R100]
needs to be cleared when in 1Gbps mode.  Older reference manuals didn't
require the explicitly clearing but has since been found it that it is
needed.
Signed-off-by: NLi Yang <leoli@freescale.com>
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>
Acked-by: NAndy Fleming <afleming@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When the napi api was changed to separate its 1:1 binding to the net_device
struct, the netif_rx_[prep|schedule|complete] api failed to remove the now
vestigual net_device structure parameter.  This patch cleans up that api by
properly removing it..
Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

gfar_poll would declare polling done once the rx queue was empty,
but the tx queue could still have packets left.

Stolen mostly from the e1000 driver.
Signed-off-by: NAndy Fleming <afleming@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

No clean up function is executed in the interrupt context by this patch.
Signed-off-by: NDai Haruki <dai.haruki@freescale.com>
Acked-by: NAndy Fleming <afleming@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Interface name (ex. eth0) is used as the prefix for the interrupt name,
with _rx, _tx, and _er appended to distinguish multiple interrupts on
the same interface.
Signed-off-by: NDai Haruki <dai.haruki@freescale.com>
Signed-off-by: NAndy Fleming <afleming@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Scatter Gather support in gianfar driver to handle fragmented frames on
the transmit side.
Signed-off-by: NPoonam Aggrwal <poonam.aggrwal@freescale.com>
Signed-off-by: NDai Haruki <dai.haruki@freescale.com>
Signed-off-by: NAndy Fleming <afleming@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The patch which fixed gianfar so it drops packets when it runs out
of memory left in the code which frees the skb when it drops packets.
Change the code so that we only free the skb if the new skb was successfully
created.
Signed-off-by: NAndy Fleming <afleming@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Whenever we want to update the status field in a BD, we usually want to
update the length field, too.  By combining them into one 32-bit field, we
reduce the number of stores to memory shared with the controller, and we
eliminate the need for order-enforcement, as the length and "READY" bit are
now updated atomically at the same time.
Signed-off-by: NDai Haruki <Dai.Haruki@freescale.com>
Signed-off-by: NAndy Fleming <afleming@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This code is based strongly on code from Dai Haruki <Dai.Haruki@freescale.com>.

The gianfar Buffer Descriptors are arranged in a circular array, the end of
which is denoted by setting the "WRAP" bit in the descriptor.  However, the
software knows the end of the ring because it knows how many descriptors are
there.  Rather than check each descriptor for whether the WRAP bit is set,
use pointer math to determine where the next BD is.  This is also useful for
when we want to look at BDs other than the very next one (for Scatter-Gather).
Signed-off-by: NAndy Fleming <afleming@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

- Also, use cacheable_memzero instead of memset for performance reasons.
Signed-off-by: NDai Haruki <dai.haruki@freescale.com>
Acked-by: NAndy Fleming <afleming@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The eTSEC can prepend up to 32 bytes to a received frame, usually for the
purpose of aligning the IP address to a word boundary, so this turns it on.

While we're in there, make the handling of the pre-frame bytes (padding and
Frame Control Block) cleaner.
Signed-off-by: NDai Haruki <dai.haruki@freescale.com>
Signed-off-by: NAndy Fleming <afleming@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Optimize the VLAN checking logic as well.
Signed-off-by: NDai Haruki <dai.haruki@freescale.com>
Acked-by: NAndy Fleming <afleming@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix some bugs in the ethtool configuration functions:
* gfar_clean_rx_ring should not be called with interrupts disabled.
* Update last transmission time to avoid tx timeout.
* Delete redundant NETIF_F_IP_CSUM check in gfar_start_xmit
* Use netif_tx_lock_bh when reconfiguring the tx csum
Signed-off-by: NDai Haruki <dai.haruki@freescale.com>
Signed-off-by: NAndy Fleming <afleming@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Store the interrupt coalescing values in the form in which they will be
written to the interrupt coalescing registers.  This puts a little overhead
into the ethtool configuration, and takes it out of the interrupt handler
Signed-off-by: NDai Haruki <dai.haruki@freescale.com>
Acked-by: NAndy Fleming <afleming@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Does the same for the accompanying MDIO driver, and then modifies the TBI
configuration method.  The old way used fields in einfo, which no longer
exists.  The new way is to create an MDIO device-tree node for each instance
of gianfar, and create a tbi-handle property to associate ethernet controllers
with the TBI PHYs they are connected to.
Signed-off-by: NAndy Fleming <afleming@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

gfar_halt does everything we want to do there, including disabling
TX/RX.  It also doesn't unnecessarily enable DMA if it's already
stopped.
Signed-off-by: NAndy Fleming <afleming@freescale.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We weren't unmapping DMA memory, which will break when gianfar gets used
on systems with more than 32-bits of memory.  Also, it's just plain wrong.
Signed-off-by: NAndy Fleming <afleming@freescale.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>