pasemi_mac: Don't enable RX/TX without a link (if possible)

Don't enable RX/TX of packets until we have a link, since there's a chance
we'll just get RX frame errors, etc.

The case where we don't have a PHY we can't do much about: Just enable
it and deal with errors as they come in.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: Print warning when not attaching to a PHY

Print a warning on the console when not connecting to a phy for an interface.
It turns out to be a pretty common problem when someone gets the MDIO info
wrong in their device tree, resulting in the macs running at a fixed 1Gbit FD.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: Remove SKB copy/recycle logic

It doesn't really buy us much, since copying is about as expensive
as the allocation in the first place. Just remove it for now.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: SKB unmap optimization

Avoid touching skb_shinfo() in the unmap path, since it turns out to
normally cause cache misses and delays. instead, save number of fragments
in the TX_RING_INFO structures since that's all that's needed anyway.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: Software-based LRO support

Implement LRO for pasemi_mac. Pretty straightforward.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: Improve RX interrupt mitigation

Currently the receive side interrupts will go off on the reception of
a packet, NAPI will poll the ring and keep polling as long as there's
a decent amount of packets to receive.

This is less than optimal, especially for LRO where it's better if we
have a more substantial amount of packets to process at once, to get
the real LRO benefits.

So, set the count threshold to a higher value and use the timeout feature
that will give us an interrupt even if not enough packets have come in
to set off the count threshold.

FIXME: It'd be real nice to have ethtool support for users to tune this
at runtime.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: Fix TX cleaning

This is a bit awkward. We don't have a timer-delayed interrupt on TX
complete, but we have a count threshold. So set that reasonably high
(32 packets), and schedule the NAPI poll when it goes off. Also bump a
regular timer that will take care of rotting packets for the last 1..31
ones in case we don't trigger a TX interrupt (and there's no RX activity
that would otherwise trigger the poll).

The longer-term fix is to separate TX from RX NAPI and do two separate
poll loops.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: performance tweaks

* Seems like we do better with a smaller RX ring, probably because chances of
  still having the SKB cached are better
* Const-ify variables to get better code generation and fewer reloads
* Move prefetching around a little, and try to prefetch the whole SKB
* Set NETIF_F_HIGHDMA
* Misc other minor tweaks
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: Convert to new dma library

Convert the pasemi_mac driver to the new platform global DMA manaagement
library. This also does a couple of other minor cleanups w.r.t. channel
management.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: Move register definitions to include/asm-powerpc

Move the common register formats and descriptor layouts from
drivers/net/pasemi_mac.h to include/asm-poewrpc/pasemi_dma.h

Previously only the ethernet driver was using them, but other drivers
are coming up that will also use them, so it makes sense to share the
constants.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: RX/TX ring management cleanup

Prepare a bit for supporting multiple TX queues by cleaning up some
of the ring management and shuffle things around a bit.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Turns out we're freeing the skb when we detect CRC error, but we're
not clearing out info->skb. We could either clear it and have the stack
reallocate it, or just leave it and the rx ring refill code will reuse
the one that was allocated.

Reusing a freed skb obviously caused some nasty crashes of various kind,
as reported by Brent Baude and David Woodhouse.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Signed-off-by: NDavid Woodhouse <dwmw2@infradead.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Make sure we don't feed packets with bad CRC up the network stack,
and discount the packet length as reported from the MAC for the CRC
field.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Don't use the "replace source address with local MAC address" bits, since
it causes problems on some variations of the hardware due to an erratum.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Add missing &:

drivers/net/pasemi_mac.c: In function 'pasemi_mac_clean_rx':
drivers/net/pasemi_mac.c:553: warning: passing argument 1 of 'prefetch'
makes pointer from integer without a cast
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: enable iommu support

Enable IOMMU support for pasemi_mac, but avoid using it on non-partitioned
systems for performance reasons.

The user can override this by selecting the PPC_PASEMI_IOMMU_DMA_FORCE
configuration option.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: use buffer index pointer in clean_rx()

Use the new features in B0 for buffer ring index on the receive side. This
means we no longer have to search in the ring for where the buffer
came from.

Also cleanup the RX cleaning side a little, while I was at it.

Note: Pre-B0 hardware is no longer supported, and needs a pile of other
workarounds that are not being submitted for mainline inclusion. So the
fact that this breaks old hardware is not a problem at this time.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: clear out old errors on interface open

Clear out any pending errors when an interface is brought up. Since the bits
are sticky, they might be from interface shutdown time after firmware has
used it, etc.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: update todo list

Remove some stale todo items that have been taken care of. Add a couple
of upcoming ones.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: further performance tweaks

Misc driver tweaks for pasemi_mac:
	* Increase ring size (really needed mostly on 10G)
	* Take out an unneeded barrier
	* Move around a few prefetches and reorder a few calls
	* Don't try to clean on full tx buffer, just let things
	  take their course and stop the queue directly
	* Avoid filling on the same line as the interface is
	  working on to reduce cache line bouncing
	* Avoid unneeded clearing of software state (and make the
	  interface shutdown code handle it)
	* Fix up some of the tx ring wrap logic.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: add local skb alignment

Add local SKB alignment to pasemi_mac, since ppc64 in general has it at 0
because of design flaws in some of the IBM server bridge chips. However,
for PWRficient doing the unaligned copies is more expensive than doing
unaligned DMA so make sure the data is aligned instead.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: workaround for erratum 5971

Implement workarounds for erratum 5971, where L2 hints aren't considered
properly unless the way hint is enabled on the interface. Since L2 isn't
setup to dedicate a way to headers, we need to reset the packet count
by hand so it won't run out of credits.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: implement sg support

Implement SG support for pasemi_mac
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: rework ring management

Rework ring management, switching to an opaque ring format instead of
the struct-based descriptor+pointer setup, since it will be needed for
SG support.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: fix bug in receive buffer dma mapping

skb->len isn't actually set to the size of the allocated skb, so don't
try to use it when figuring out how much to map.

(This hasn't surfaced as a real bug because we effectively disable
translation for the interface, but it still needs fixing for the future)
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: basic error checking

Add some rudimentary error checking to pasemi_mac.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: pass in count of buffers to replenish rx ring with

Refactor replenish_rx_ring to take an argument for how many entries to
fill. Since it's normally available from where it's called anyway, this
is just simpler. It also removes the awkward logic to try to figure out
if we're filling for the first time or not.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: don't enable rx before there are buffers on the ring

Reorder initialization of the DMA channels and the interface. Before there
was a time window when the interface was enabled before DMA was enabled.
Also, now there will always be RX buffers available at the time the
MAC interface is enabled, to avoid temporary out-of-buffer errors for the
very first packets (on busy networks).
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: flags as passed to spin_*_irqsave() should be unsigned long.
Signed-off-by: NTony Breeds <tony@bakeyournoodle.com>
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

pasemi_mac: set interface speed correctly on XAUI ports

Set interface speed for XAUI to 10G per default, not 1G.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

drivers/net/pasemi_mac.c: At top level:
drivers/net/pasemi_mac.c:89: warning: 'read_iob_reg' defined but not used
Signed-off-by: NSatyam Sharma <satyam@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This is nicer than the MAC_FMT stuff.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We now have struct net_device_stats embedded in struct net_device,
and the default ->get_stats() hook does the obvious thing for us.

Run through drivers/net/* and remove the driver-local storage of
statistics, and driver-local ->get_stats() hook where applicable.

This was just the low-hanging fruit in drivers/net; plenty more drivers
remain to be updated.

[ Resolved conflicts with napi_struct changes and fix sunqe build
  regression... -DaveM ]
Signed-off-by: NJeff Garzik <jeff@garzik.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It's been a useless no-op for long enough in 2.6 so I figured it's time to
remove it.  The number of people that could object because they're
maintaining unified 2.4 and 2.6 drivers is probably rather small.

[ Handled drivers added by netdev tree and some missed IRDA cases... -DaveM ]
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>
Signed-off-by: NJeff Garzik <jeff@garzik.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Unfortunately there's no timeout for how long a packet can sit on
the TX ring after completion before an interrupt is generated, and
we want to have a threshold that's larger than one packet per interrupt.

So we have to have a timer that occasionally cleans the TX ring even
though there hasn't been an interrupt. Instead of setting up a dedicated
timer for this, just clean it in the NAPI poll routine instead.

[ Resolved conflicts with napi_struct changes... -DaveM ]
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Enable LLTX on pasemi_mac: we're already doing sufficient locking
in the driver to enable it.

[ Resolved merge conflicts with napi_struct changes... -DaveM ]
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

RX side flag to use is CHECKSUM_UNNECESSARY, not CHECKSUM_COMPLETE.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

The old logic didn't detect full (tx) ring cases properly, causing
overruns and general badness. Clean it up a bit and abstract out the
ring size checks, always making sure to leave 1 slot open.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

Postpone pci unmap and skb free of the transmitted buffers to outside of
the tx ring lock, batching them up 32 at a time.

Also increase the count threshold to 128.
Signed-off-by: NOlof Johansson <olof@lixom.net>
Signed-off-by: NJeff Garzik <jeff@garzik.org>