Recycling turns out to be a bad idea!  For most use cases, the
packet can not be reused: TCP packets are cloned. Even for the ideal
case of forwarding, it hurts performance because of CPU ping/pong.
On a multi-core system forwarding of 64 byte packets is worse
much worse: recycling = 24% forwarded vs no recycling = 42% forwarded
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Don't reference the list element in hardware transmit ring on transmit
completion. The list element is updated by hardware, therefore
it causes a cache miss. Do book keeping in software structure.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Allocate and size transmit ring based on parameters. Saves excess
space and allows configuring larger rings for testing.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch saves elements on transmit ring by only updating the upper
64 bit address when it changes. With many workloads skb's are located
in same region, so it saves space.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The whole restarting flag was introduced by Mike McCormack
and was a temporary duct tape patch around issues with transmits
inflight during restart. The problems it was covering are now
fixed and the code should have been reverted.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The sky2 driver combines auto speed negotiation with automatic negotiation
of pause parameters; but the ethtool interface expects them to be
split. This patch allows autonegotiation to be used for speed, but
manually disable flow control.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch supersedes my previous patch "sky2: Avoid transmitting
during sky2_restart".

I have reworked the patch to avoid crashes during both sky2_restart()
and sky2_set_ringparam().

Without this patch, the sky2 driver can be crashed by doing:

# pktgen eth1 &    (transmit many packets on eth1)
# ethtool -G eth1 tx 510

I am aware you object to storing extra state, but I can't see a way
around this. Without remembering that we're restarting,
netif_wake_queue() is called in the ISR from sky2_tx_complete(), and
netif_tx_lock() is used in sky2_tx_done().  If anybody can see a way
around this, please let me know.
Signed-off-by: NMike McCormack <mikem@ring3k.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This patch implements skb recycling. It reclaims transmitted skb's
for use in the receive ring.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Fix the problems reported for 2.6.27-rc1 caused by over aggressive
power management. Turning clock off on PCI Express is problematic for WOL,
and when doing multi-booting.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Add support for Yukon 2 Ultra 2 chip set (88E8057) based on code in latest
version of vendor driver (sk98lin 10.60.2.3).  Untested on real hardware.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Turn on special bits to save more power when device is shutdown.
Tested on a limited range of hardware, some of the bits are for hardware
that probably isn't even in production (like Yukon Supreme) and was ported
from the vendor driver.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Put PHY int sleep mode (from vendor sk98lin 10.50 driver) when the
network device is brought down.
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

noticed while browsing code, apparent thinko.  compile tested only.
Signed-off-by: NJesse Brandeburg <jesse.brandeburg@intel.com>
CC: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jgarzik@redhat.com>

Fix problems in LED management, so ethtool -p works correctly on Yukon-EC
and other chips. The driver was incorrectly setting the PHY LED overide bits.
Moral: read the spec sheet, not the vendor driver.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

The Yukon FE chip has a ram buffer therefore it needs the alignment
restriction and hang check workarounds.

Therefore:
  * Autodetect the prescence/absence of ram buffer
  * Rename the flag value to reflect this
  * Use it consistently (ie don't reread register)
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Add support from sk98lin vendor driver 10.50.1.3 for 88E8055 and
88E8075 chips.  I don't have this hardware to test, so this changes
are untested.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

This patch might fix problems with 4G or more of memory.
It stops the driver from doing a small optimization for Tx and Rx,
and instead always sets the high-page on tx/rx descriptors.

Fixes-bug: http://bugzilla.kernel.org/show_bug.cgi?id=9725Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Using the hardware window into PCI config space is more reliable
and smaller/faster than using the pci_config routines. It avoids issues
with MMCONFIG etc.

Reverts: 167f53d0

Please apply for 2.6.24
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

The PCI AER support may not work for a couple of reasons.
It may not be configured into the kernel or there may be a BIOS
bug that prevents MMCONFIG from working.  If MMCONFIG doesn't work
then the PCI registers that control AER will not be accessible via
pci_read_config functions; luckly there is another window to access
PCI space in the device, so use that.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Use builtin statistics structure from net device.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use the PCI layer config access functions. The driver was using the
memory mapped window in device, to workaround issues accessing the
advanced error reporting registers.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Use the kernel interfaces for advanced error reporting.
This should be cleaner and clear up errors on boot.

For those systems with busted BIOS's that don't correctly
support mmconfig, advanced error reporting will be disabled.
The PCI registers for advanced error reporting start at 0x100 which
is too large to be accessed by legacy functions.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Add documentation of GPHY_CTRL register bits even if driver
is not using them (yet).
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Several devices have multiple independant RX queues per net
device, and some have a single interrupt doorbell for several
queues.

In either case, it's easier to support layouts like that if the
structure representing the poll is independant from the net
device itself.

The signature of the ->poll() call back goes from:

	int foo_poll(struct net_device *dev, int *budget)

to

	int foo_poll(struct napi_struct *napi, int budget)

The caller is returned the number of RX packets processed (or
the number of "NAPI credits" consumed if you want to get
abstract).  The callee no longer messes around bumping
dev->quota, *budget, etc. because that is all handled in the
caller upon return.

The napi_struct is to be embedded in the device driver private data
structures.

Furthermore, it is the driver's responsibility to disable all NAPI
instances in it's ->stop() device close handler.  Since the
napi_struct is privatized into the driver's private data structures,
only the driver knows how to get at all of the napi_struct instances
it may have per-device.

With lots of help and suggestions from Rusty Russell, Roland Dreier,
Michael Chan, Jeff Garzik, and Jamal Hadi Salim.

Bug fixes from Thomas Graf, Roland Dreier, Peter Zijlstra,
Joseph Fannin, Scott Wood, Hans J. Koch, and Michael Chan.

[ Ported to current tree and all drivers converted.  Integrated
  Stephen's follow-on kerneldoc additions, and restored poll_list
  handling to the old style to fix mutual exclusion issues.  -DaveM ]
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Be more selective about when to enable the ram buffer watchdog code.
It is unnecessary on XL A3 or later revs, and with Yukon FE
the buffer is so small (4K) that the watchdog detects false positives.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

A driver writer from another operating system hinted that
the versions of Yukon 2 chip with rambuffer (EC and XL) have
a hardware bug that if the FIFO ever gets completely full it
will hang. Sounds like a classic ring full vs ring empty wrap around
bug.

As a workaround, use the existing watchdog timer to check for
ring full lockup.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Add support for newest Marvell chips.
The Yukon FE plus chip is found in some not yet released laptops.
Tested on hardware evaluation boards.

This version of the patch is for 2.6.23. It supersedes
the two previous patches that are sitting in netdev-2.6 (upstream branch).
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

This patch should cause no functional changes in driver behaviour.
There are (too) many revisions of the Yukon 2 chip now. Instead of
adding more conditionals based on chip revision; rerganize into a
set of feature flags so adding new versions is less problematic.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

The length check for truncated frames was not correctly handling
the case where VLAN acceleration had already read the tag.
Also, the Yukon EX has some features that use high bit of status
as security tag.
Signed-off-by: NPierre-Yves Ritschard <pyr@spootnik.org>
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

This fixes the extra timer overhead that people were whining about
as a 2.6.23 regression.

Running the watchdog timer all the time is unneeded. Change it
to run only if link is up, and reduce frequency to save power.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Add an optional debug interface for displaying state of transmit/receive
rings. Creates a file debugfs/sky2/ethX for each device that is up.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Enable support for Yukon EX chipset (88e8071).
Most of changes are related to new commands to chip for transmit,
and change in status and checksumming.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

The General Purpose I/O register is yet another hardware workaround
catchall. Enable workaround that vendor driver does to stay
but for bug compatiable.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

This register is more of a test and control register on Yukon2.
So rename it to Q_TEST and give some bit definitions.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Need to setup more PCI control control registers are on Yukon EX.
Some of these also exist on Yukon EC-U as well.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Don't want IRQ on FIFO error because there is nothing useful to do with it.
But do want IRQ on duplex change.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

This code inherited from the sk98lin driver is incorrect on the Yukon2.
The GPHY_CTRL register values are specific to the internal PHY of the chip
and the values used were leftovers.
Driver was setting bit 13 which is now the INT polarity for the PHY!
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

The Yukon EC Ultra chips have transmit settings for store and
forward and PCI buffering. By setting these appropriately, normal
performance goes from 750Mbytes/sec to 940Mbytes/sec (non-jumbo).

It is also possible to do Jumbo mode, but it means turning off
TSO and checksum offload so the performance gets worse. There isn't
enough buffering for checksum offload to work.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

There should never be descriptor error unless hardware or driver is buggy.
But if an error occurs, print useful information, clear irq, and recover.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

The transmit timeout code could hang, and it would not clear out
problems if the hardware was stuck.  Change the code to effectively do
a device down/up similar to the suspend/resume code.
Signed-off-by: NStephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>