linux-stable.git/drivers/net/gianfar.c, branch linux-2.6.28.y

gianfar: Fix DMA unmap invocations

2008-11-14T23:18:30+00:00

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: Andy Fleming 
Signed-off-by: Jeff Garzik

gianfar: Don't reset TBI<->SerDes link if it's already up

2008-10-31T04:59:53+00:00

The link may be up already via the chip's reset strapping, or though action
of U-Boot, or from the last time the interface was brought up.  Resetting
the link causes it to go down for several seconds.  This can significantly
increase the time from power-on to DHCP completion and a device being
accessible to the network.

Signed-off-by: Trent Piepho 
Acked-by: Andy Fleming 
Signed-off-by: Jeff Garzik

gianfar: Fix race in TBI/SerDes configuration

2008-10-31T04:59:46+00:00

The init_phy() function attaches to the PHY, then configures the
SerDes<->TBI link (in SGMII mode).  The TBI is on the MDIO bus with the PHY
(sort of) and is accessed via the gianfar's MDIO registers, using the
functions gfar_local_mdio_read/write(), which don't do any locking.

The previously attached PHY will start a work-queue on a timer, and
probably an irq handler as well, which will talk to the PHY and thus use
the MDIO bus.  This uses phy_read/write(), which have locking, but not
against the gfar_local_mdio versions.

The result is that PHY code will try to use the MDIO bus at the same time
as the SerDes setup code, corrupting the transfers.

Setting up the SerDes before attaching to the PHY will insure that there is
no race between the SerDes code and *our* PHY, but doesn't fix everything.
Typically the PHYs for all gianfar devices are on the same MDIO bus, which
is associated with the first gianfar device.  This means that the first
gianfar's SerDes code could corrupt the MDIO transfers for a different
gianfar's PHY.

The lock used by phy_read/write() is contained in the mii_bus structure,
which is pointed to by the PHY.  This is difficult to access from the
gianfar drivers, as there is no link between a gianfar device and the
mii_bus which shares the same MDIO registers.  As far as the device layer
and drivers are concerned they are two unrelated devices (which happen to
share registers).

Generally all gianfar devices' PHYs will be on the bus associated with the
first gianfar.  But this might not be the case, so simply locking the
gianfar's PHY's mii bus might not lock the mii bus that the SerDes setup
code is going to use.

We solve this by having the code that creates the gianfar platform device
look in the device tree for an mdio device that shares the gianfar's
registers.  If one is found the ID of its platform device is saved in the
gianfar's platform data.

A new function in the gianfar mii code, gfar_get_miibus(), can use the bus
ID to search through the platform devices for a gianfar_mdio device with
the right ID.  The platform device's driver data is the mii_bus structure,
which the SerDes setup code can use to lock the current bus.

Signed-off-by: Trent Piepho 
CC: Andy Fleming 
Signed-off-by: Jeff Garzik

gianfar: fix handle errors returned by platform_get_irq*()

2008-10-22T10:22:07+00:00

platform_get_irq*() returns on -ENXIO when the resource cannot be
found, but this remains unnoticed if stored in an unsigned.

Signed-off-by: Roel Kluin 
Signed-off-by: Jeff Garzik

gianfar: Create net device with carrier down

2008-10-09T00:03:12+00:00

The device's carrier status is controlled via the functions
netif_carrier_on() and netif_carrier_off().  These set or clear a bit
indicating the carrier (aka lower level link) is down, and if the state
changed, they fire off a routing netlink event.

Add a call to netif_carrier_off() before register_netdev() so that the
newly created device will be set to carrier down.  Then when the carrier
comes up for the first time, a netlink event will be generated, as the
carrier changed from down to up.  Otherwise the initial carrier up will
appear to be changing the status from up to up, and so no event is
generated since that's not a change.

Signed-off-by: Trent Piepho 
Signed-off-by: David S. Miller

net: don't grab a mutex within a timer context in gianfar

2008-08-27T09:55:19+00:00

I got the following backtrace while network was unavailble:

|NETDEV WATCHDOG: eth0: transmit timed out
|BUG: sleeping function called from invalid context at /home/bigeasy/git/linux-2.6-powerpc/kernel/mutex.c:87
|in_atomic():1, irqs_disabled():0
|Call Trace:
|[c0383d90] [c0006dd8] show_stack+0x48/0x184 (unreliable)
|[c0383db0] [c001e938] __might_sleep+0xe0/0xf4
|[c0383dc0] [c025a43c] mutex_lock+0x24/0x3c
|[c0383de0] [c019005c] phy_stop+0x20/0x70
|[c0383df0] [c018d4ec] stop_gfar+0x28/0xf4
|[c0383e10] [c018e8c4] gfar_timeout+0x30/0x60
|[c0383e20] [c01fe7c0] dev_watchdog+0xa8/0x144
|[c0383e30] [c002f93c] run_timer_softirq+0x148/0x1c8
|[c0383e60] [c002b084] __do_softirq+0x5c/0xc4
|[c0383e80] [c00046fc] do_softirq+0x3c/0x54
|[c0383e90] [c002ac60] irq_exit+0x3c/0x5c
|[c0383ea0] [c000b378] timer_interrupt+0xe0/0xf8
|[c0383ec0] [c000e5ac] ret_from_except+0x0/0x18
|[c0383f80] [c000804c] cpu_idle+0xcc/0xdc
|[c0383fa0] [c025c07c] etext+0x7c/0x90
|[c0383fc0] [c0338960] start_kernel+0x294/0x2a8
|[c0383ff0] [c00003dc] skpinv+0x304/0x340
|------------[ cut here ]------------

The phylock was once a spinlock but got changed into a mutex via
commit 35b5f6b1a aka [PHYLIB: Locking fixes for PHY I/O potentially sleeping]

Signed-off-by: Sebastian Siewior 
Signed-off-by: Jeff Garzik

gianfar: Call gfar_halt_nodisable() from gfar_halt().

2008-08-14T08:26:57+00:00

gfar_halt() was factored out into halting and disabling by commit
d87eb12785c14de1586e3bad86ca2c0991300339, as the suspend() method
only wants to do the former.  However, the call to gfar_halt_nodisable()
from gfar_halt() apparently got lost during the patch respin process.

This adds it back.

Signed-off-by: Scott Wood 
Signed-off-by: Jeff Garzik

remove bogus CONFIG_GFAR_NAPI's

2008-08-07T06:11:05+00:00

The commit that made the CONFIG_GFAR_NAPI code unconditional was
included at the same time as a new CONFIG_GFAR_NAPI user, resulting
in these bugus #ifdef's.

Reported-by: Robert P. J. Day 
Signed-off-by: Adrian Bunk 
Signed-off-by: Jeff Garzik

Merge commit 'origin/master'

2008-07-22T07:12:37+00:00

Manually fixed up:

	drivers/net/fs_enet/fs_enet-main.c

gianfar: do not touch net queue in adjust_link phylib callback

2008-07-21T15:29:54+00:00

If the net queue has not been started, we'll get this nice oops
and non-working ethernet:

PHY: 0:01 - Link is Up - 1000/Full
------------[ cut here ]------------
kernel BUG at net/core/dev.c:1328!
Oops: Exception in kernel mode, sig: 5 [#1]
MPC837x RDB
Modules linked in:
NIP: c02544a0 LR: c01a17d0 CTR: c01a16ac
REGS: cf837e40 TRAP: 0700   Not tainted  (2.6.26-05253-g14b395e)
MSR: 00021032   CR: 22042044  XER: 00000000
TASK = cf819400[5] 'events/0' THREAD: cf836000
GPR00: c01a17d0 cf837ef0 cf819400 c03d8d08 cf8469a0 00000064 00000000 00000000
GPR08: c03d8d08 00000001 00000001 cf899ba0 22044044 00000000 0fffd000 00000000
GPR16: 0fff3028 0fff6cf0 00000000 0fff8390 0ff494a0 00000004 00000000 00000000
GPR24: c0361a00 00001058 cf9f6600 00009032 cf846800 cf846b80 00000001 00000014
NIP [c02544a0] __netif_schedule+0x28/0x8c
LR [c01a17d0] adjust_link+0x124/0x1cc
Call Trace:
[cf837ef0] [c03fb3a0] 0xc03fb3a0 (unreliable)
[cf837f10] [c01a17d0] adjust_link+0x124/0x1cc
[cf837f40] [c01a8e28] phy_state_machine+0x2e0/0x448
[cf837f60] [c0040254] run_workqueue+0xc8/0x168
[cf837f90] [c00408d8] worker_thread+0x70/0xd0
[cf837fd0] [c0044630] kthread+0x48/0x84
[cf837ff0] [c0012610] kernel_thread+0x44/0x60
Instruction dump:
7c0803a6 4e800020 3d20c03e 9421ffe0 7c0802a6 7c681b78 39298d08 7c694a78
7d290034 90010024 bfa10014 5529d97e <0f090000> 39600002 38030024 7d200028
---[ end trace 13dfd73ee42d0c30 ]---

Since the driver is using phylib (which is doing netif_carrier_on/off()),
we should simply remove netif_tx_schedule_all() from adjust_link().

Signed-off-by: Anton Vorontsov 
Signed-off-by: David S. Miller