Even through the usage of devm_*() functions is generally recommended
over their classic variants, in the case of devm_request_irq()
combined with irq_of_parse_and_map(), it doesn't work nicely.

We have the following scenario:

 irq_of_parse_and_map(...)
 devm_request_irq(...)

For some reason, the driver initialization fails at a later
point. Since irq_of_parse_and_map() is no device-managed, we do a:

 irq_dispose_mapping(...)

Unfortunately, this doesn't work, because the free_irq() must be done
prior to calling irq_dispose_mapping(). But with the devm mechanism,
the automatic free_irq() would happen only after we get out of the
->probe() function.

So basically, we revert to using request_irq() with traditional error
handling, so that in case of error, free_irq() gets called before
irq_dispose_mapping().
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

The XOR channels on Marvell SoCs have a Window Override Control
register that allow to do some fancy things with addresses. Those
features are not used by the driver, but some U-Boot versions anyway
modify those registers.

For some reason, the U-Boot on OpenBlocks AX3-4 was setting an invalid
value in those registers when the addition 2 GB DRAM chip was plugged
into the board, causing the XOR driver to fail in using the XOR
engines.

By setting those registers to 0 during the driver initialization, we
ensure that the registers are configured according with the driver
operation model.

Thanks to Lior Amsalem <alior@marvell.com> for his help in debugging
this problem.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

mvneta_deinit() can be called from the ->probe() hook in the error
path, so it shouldn't be marked as __devexit. It fixes the following
section mismatch warning:

WARNING: vmlinux.o(.devinit.text+0x239c): Section mismatch in reference
from the function mvneta_probe() to the function .devexit.text:mvneta_deinit()
The function __devinit mvneta_probe() references
a function __devexit mvneta_deinit().
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

Now that the Armada 370/XP platform has gained proper integration with
the clock framework, we add clk support in the Marvell Armada 370/XP
Ethernet driver.

Since the existing Device Tree binding that exposes a
'clock-frequency' property has never been exposed in any stable kernel
release, we take the freedom of removing this property to replace it
with the standard 'clocks' clock pointer property.

The Device Tree binding documentation is updated accordingly.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

As reported by checkpatch, the multiline comments for net/ and
drivers/net/ have a slightly different format than the one used in the
rest of the kernel, so we adjust our multiline comments accordingly.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

As reported by checkpatch, the multiline comments for net/ and
drivers/net/ have a slightly different format than the one used in the
rest of the kernel, so we adjust our multiline comment accordingly.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

As suggested by checkpatch, using <linux/delay.h> instead of
<asm/delay.h> is appropriate.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

The dmatest module for DMA engines calls

device_control(dtc->chan, DMA_TERMINATE_ALL, 0);

after completing the tests. The documentation in
include/linux/dmaengine.h suggests this function is optional and
dma_async_device_register() also does not BUG_ON() when not passed a
function. However, dmatest is not the only code in the kernel
unconditionally calling device_control. So add an implementation
indicating all operations are not implemented.
Signed-off-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

The ->probe() and ->remove() functions were missing the usual
__devinit and __devexit qualifiers.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

This patch finally adds a Device Tree binding to the mv_xor
driver. Thanks to the previous cleanup patches, the Device Tree
binding is relatively simply: one DT node per XOR engine, with
sub-nodes for each XOR channel of the XOR engine. The binding
obviously comes with the necessary documentation.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Cc: devicetree-discuss@lists.ozlabs.org

Even though the driver cannot be unloaded at the moment, it is still
good to properly free the IRQ handlers in the channel removal function.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

The pool_size is always PAGE_SIZE, and since it is a software
configuration paramter (and not a hardware description parameter), we
cannot make it part of the Device Tree binding, so we'd better remove
it from the platform_data as well.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

There is no need for the platform_data to give this ID, it is simply
the channel number, so we can compute it inside the driver when
registering the channels.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

The backpointer from mv_xor_chan to mv_xor_device is now useless, get
rid of it.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

Now that mv_xor_device is no longer used to designate the per-channel
DMA devices, use it know to designate the XOR engine themselves
(currently composed of two XOR channels).

So, now we have the nice organization where:

 - mv_xor_device represents each XOR engine in the system
 - mv_xor_chan   represents each XOR channel of a given XOR engine
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

Even though the DMA engine infrastructure has support for multiple
channels per device, the mv_xor driver registers one DMA engine device
for each channel, because the mv_xor channels inside the same XOR
engine have different capabilities, and the DMA engine infrastructure
only allows to express capabilities at the DMA engine device level.

The mv_xor driver has therefore been registering one DMA engine device
and one DMA engine channel for each XOR channel since its introduction
in the kernel. However, it kept two separate internal structures,
mv_xor_device and mv_xor_channel, which didn't make a lot of sense
since there was a 1:1 mapping between those structures.

This patch gets rid of this duplication, and merges everything into
the mv_xor_chan structure.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

In preparation for the removal of the mv_xor_device structure, we
directly pass mv_xor_chan pointers to the self-test functions included
in the driver. These functions were anyway selecting the first (and
only channel) available in each DMA device, so the behaviour is
unchanged.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

The mv_xor_device structure embeds a 'struct dma_device', which is
named 'common', a not very meaningful name. Rename it to 'dmadev',
which will help avoid confusions later as we merge the mv_xor_device
and mv_xor_chan structures together.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

The mv_xor_chan structure embeds a 'struct dma_chan', which is named
'common', a not very meaningful name. Rename it to 'dmachan', which
will help avoid confusions later as we merge the mv_xor_device and
mv_xor_chan structures together.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

It was only used in places where we could get the 'struct device *'
pointer through a different way.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

In many place, we need to get the 'struct device *' pointer from a
'struct mv_chan *', so we add a helper that makes this a bit
easier. It will also help reducing the change noise in further
patches.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

In mv_xor_memcpy_self_test() and mv_xor_xor_self_test(), all DMA
functions are called by passing dma_chan->device->dev as the 'device
*', except the calls to dma_sync_single_for_cpu() which uselessly goes
through mv_chan->device->pdev->dev.

Simplify this by using dma_chan->device->dev direclty in
dma_sync_single_for_cpu() calls.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

The to_mv_xor_device() macro is not being used by the driver, so we
can get rid of it.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

The 'shared' word no longer makes sense in a number of places as we
renamed the 'mv_xor_shared' driver to 'mv_xor'.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

Since we got rid of the per-XOR channel 'mv_xor' driver, now the
per-XOR engine driver that used to be called 'mv_xor_shared' can
simply be named 'mv_xor'.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

'struct mv_xor_shared_platform_data' used to be the platform_data
structure for the 'mv_xor_shared', but this driver is going to be
renamed simply 'mv_xor', so also rename its platform_data structure
accordingly.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

mv_xor_platform_data used to be the platform_data structure associated
to the 'mv_xor' driver. This driver no longer exists, and this data
structure really contains the properties of each XOR channel part of a
given XOR engine. Therefore 'struct mv_xor_channel_data' is a more
appropriate name.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

Now that XOR channels are directly registered by the main
'mv_xor_shared' device ->probe() function and all users of the
'mv_xor' device have been removed, we can get rid of the latter.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

Extend the XOR engine driver (currently called "mv_xor_shared") so
that XOR channels can be passed in the platform_data structure, and be
registered from there.

This will allow the users of the driver to be converted to the single
platform_driver variant of the mv_xor driver.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

Instead of doing the initialization/cleanup of the XOR channels
directly in the ->probe() and ->remove() hooks, we create separate
utility functions mv_xor_channel_add() and mv_xor_channel_remove().

This will allow to easily introduce in a future patch a different way
of registering XOR channels: instead of having one platform_device per
channel, we'll trigger the registration of all XOR channels of a given
XOR engine directly from the XOR engine ->probe() function.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

The driver currently pokes into the platform_data structure during its
normal operation to get the pool_size value. Poking into the
platform_data structure is not nice when moving to the Device Tree, so
this commit adds a new pool_size field in the mv_xor_device structure,
which gets initialized at ->probe() time. The driver then uses this
field instead of the platform_data.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

The usage of dev_printk() is deprecated, and the dev_err(), dev_info()
and dev_notice() functions should be used instead.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

Signed-off-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Tested-by Gregory CLEMENT <gregory.clement@free-electrons.com>

Signed-off-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>

This driver allows to provide DT clocks for clock gates found on
Marvell Dove and Kirkwood SoCs. The clock gates are referenced by
the phandle index of the corresponding bit in the clock gating control
register to ease lookup in the datasheet.
Signed-off-by: NSebastian Hesselbarth <sebastian.hesselbarth@gmail.com>

Add Armada 370/XP specific CPU clocks
Signed-off-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Tested-by: NGregory CLEMENT <gregory.clement@free-electrons.com>

This driver allows to provide DT clocks for core clocks found on
Marvell Kirkwood, Dove & 370/XP SoCs. The core clock frequencies and
ratios are determined by decoding the Sample-At-Reset registers.

Although technically correct, using a divider of 0 will lead to
div_by_zero panic. Let's use a ratio of 0/1 instead to fail later
with a zero clock.
Signed-off-by: NGregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: NSebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
Signed-off-by: NAndrew Lunn <andrew@lunn.ch>
Tested-by Gregory CLEMENT <gregory.clement@free-electrons.com>

Fix rapidio kernel-doc warnings:

  Warning(drivers/rapidio/rio.c:415): No description found for parameter 'local'
  Warning(drivers/rapidio/rio.c:415): Excess function parameter 'lstart' description in 'rio_map_inb_region'
  Warning(include/linux/rio.h:290): No description found for parameter 'switches'
  Warning(include/linux/rio.h:290): No description found for parameter 'destid_table'
Signed-off-by: NRandy Dunlap <rdunlap@infradead.org>
Cc: Matt Porter <mporter@kernel.crashing.org>
Acked-by: NAlexandre Bounine <alexandre.bounine@idt.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch contains a new network driver for the network unit of the
ARM Marvell Armada 370 and the Armada XP. Both SoCs use the PJ4B
processor, a Marvell-developed ARM core that implements the ARMv7
instruction set.

Compared to previous ARM Marvell SoCs (Kirkwood, Orion, Discovery),
the network unit in Armada 370 and Armada XP is highly different. This
is the reason why this new 'mvneta' driver is needed, while the older
ARM Marvell SoCs use the 'mv643xx_eth' driver.

Here is an overview of the most important hardware changes that
require a new, specific, driver for the network unit of Armada 370/XP:

 - The new network unit has a completely different design and layout
   for the RX and TX descriptors. They are now organized as a simple
   array (each RX and TX queue has base address and size of this
   array) rather than a linked list as in the old SoCs.

 - The new network unit has a different RXQ and TXQ management: this
   management is done using special read/write counter registers,
   while in the Old SocS, it was done using the Ownership bit in RX
   and TX descriptors.

 - The new network unit has different interrupt registers

 - The new network unit way of cleaning of interrupts is not done by
   writing to the cause register, but by updating per-queue counters

 - The new network unit has different GMAC registers (link, speed,
   duplex configuration) and different WRR registers.

 - The new network unit has lots of new units like PnC (Parser and
   Classifier), PMT, BM (Memory Buffer Management), xPON, and more.

The driver proposed in the current patch only handles the basic
features. Additional hardware features will progressively be supported
as needed.

This code has originally been written by Rami Rosen
<rosenr@marvell.com>, and then reviewed and cleaned up by Thomas
Petazzoni <thomas.petazzoni@free-electrons.com>.
Signed-off-by: NThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: NDavid S. Miller <davem@davemloft.net>