When newer revisions of the Axienet IP are configured for a 64-bit bus,
we *need* to write to the MSB part of the an address registers,
otherwise the IP won't recognise this as a DMA start condition.
This is even true when the actual DMA address comes from the lower 4 GB.

To autodetect this configuration, at probe time we write all 1's to such
an MSB register, and see if any bits stick. If this is configured for a
32-bit bus, those MSB registers are RES0, so reading back 0 indicates
that no MSB writes are necessary.
On the other hands reading anything other than 0 indicated the need to
write the MSB registers, so we set the respective flag.

The actual DMA mask stays at 32-bit for now. To help bisecting, a
separate patch will enable allocations from higher addresses.
Signed-off-by: NAndre Przywara <andre.przywara@arm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Newer revisions of the AXI DMA IP (>= v7.1) support 64-bit addresses,
both for the descriptors itself, as well as for the buffers they are
pointing to.
This is realised by adding "MSB" words for the next and phys pointer
right behind the existing address word, now named "LSB". These MSB words
live in formerly reserved areas of the descriptor.

If the hardware supports it, write both words when setting an address.
The buffer address is handled by two wrapper functions, the two
occasions where we set the next pointers are open coded.

For now this is guarded by a flag which we don't set yet.
Signed-off-by: NAndre Przywara <andre.przywara@arm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Newer versions of the Xilink DMA IP support busses with more than 32
address bits, by introducing an MSB word for the registers holding DMA
pointers (tail/current, RX/TX descriptor addresses).
On IP configured for more than 32 bits, it is also *required* to write
both words, to let the IP recognise this as a start condition for an
MM2S request, for instance.

Wrap the DMA pointer writes with a separate function, to add this
functionality later. For now we stick to the lower 32 bits.
Signed-off-by: NAndre Przywara <andre.przywara@arm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

mii-tool is useful for debugging, and all it requires to work is to wire
up the ioctl ops function pointer.
Add this to the axienet driver to enable mii-tool.
Signed-off-by: NAndre Przywara <andre.przywara@arm.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Newer revisions of the IP don't have these registers. Since we don't
really use them, just drop them from the ethtools dump.
Signed-off-by: NAndre Przywara <andre.przywara@arm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

According to the DT binding, the Ethernet core interrupt is optional.

Use platform_get_irq_optional() to avoid the error message when the
IRQ is not specified.
Signed-off-by: NAndre Przywara <andre.przywara@arm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Especially with the default 32-bit DMA mask, DMA buffers are a limited
resource, so their allocation can fail.
So as the DMA API documentation requires, add error checking code after
dma_map_single() calls to catch the case where we run out of "low" memory.
Signed-off-by: NAndre Przywara <andre.przywara@arm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Factor out the code that cleans up a number of connected TX descriptors,
as we will need it to properly roll back a failed _xmit() call.
There are subtle differences between cleaning up a successfully sent
chain (unknown number of involved descriptors, total data size needed)
and a chain that was about to set up (number of descriptors known), so
cater for those variations with some extra parameters.
Signed-off-by: NAndre Przywara <andre.przywara@arm.com>
Reviewed-by: NRadhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since 0 is a valid DMA address, we cannot use the physical address to
check whether a TX descriptor is valid and is holding a DMA mapping.

Use the "cntrl" member of the descriptor to make this decision, as it
contains at least the length of the buffer, so 0 points to an
uninitialised buffer.
Signed-off-by: NAndre Przywara <andre.przywara@arm.com>
Reviewed-by: NRadhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When axienet_dma_bd_init() bails out during the initialisation process,
it might do so with parts of the structure already allocated and
initialised, while other parts have not been touched yet. Before
returning in this case, we call axienet_dma_bd_release(), which does not
take care of this corner case.
This is most obvious by the first loop happily dereferencing
lp->rx_bd_v, which we actually check to be non NULL *afterwards*.

Make sure we only unmap or free already allocated structures, by:
- directly returning with -ENOMEM if nothing has been allocated at all
- checking for lp->rx_bd_v to be non-NULL *before* using it
- only unmapping allocated DMA RX regions

This avoids NULL pointer dereferences when initialisation fails.
Signed-off-by: NAndre Przywara <andre.przywara@arm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

When we fail allocating the DMA buffers in axienet_dma_bd_init(), we
report this error, but carry on with initialisation nevertheless.

This leads to a kernel panic when the driver later wants to send a
packet, as it uses uninitialised data structures.

Make the axienet_device_reset() routine return an error value, as it
contains the DMA buffer initialisation. Make sure we propagate the error
up the chain and eventually fail the driver initialisation, to avoid
relying on non-initialised buffers.
Signed-off-by: NAndre Przywara <andre.przywara@arm.com>
Reviewed-by: NRadhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The DMA error handler routine is currently a tasklet, scheduled to run
after the DMA error IRQ was handled.
However it needs to take the MDIO mutex, which is not allowed to do in a
tasklet. A kernel (with debug options) complains consequently:
[  614.050361] net eth0: DMA Tx error 0x174019
[  614.064002] net eth0: Current BD is at: 0x8f84aa0ce
[  614.080195] BUG: sleeping function called from invalid context at kernel/locking/mutex.c:935
[  614.109484] in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 40, name: kworker/u4:4
[  614.135428] 3 locks held by kworker/u4:4/40:
[  614.149075]  #0: ffff000879863328 ((wq_completion)rpciod){....}, at: process_one_work+0x1f0/0x6a8
[  614.177528]  #1: ffff80001251bdf8 ((work_completion)(&task->u.tk_work)){....}, at: process_one_work+0x1f0/0x6a8
[  614.209033]  #2: ffff0008784e0110 (sk_lock-AF_INET-RPC){....}, at: tcp_sendmsg+0x24/0x58
[  614.235429] CPU: 0 PID: 40 Comm: kworker/u4:4 Not tainted 5.6.0-rc3-00926-g4a165a9d5921 #26
[  614.260854] Hardware name: ARM Test FPGA (DT)
[  614.274734] Workqueue: rpciod rpc_async_schedule
[  614.289022] Call trace:
[  614.296871]  dump_backtrace+0x0/0x1a0
[  614.308311]  show_stack+0x14/0x20
[  614.318751]  dump_stack+0xbc/0x100
[  614.329403]  ___might_sleep+0xf0/0x140
[  614.341018]  __might_sleep+0x4c/0x80
[  614.352201]  __mutex_lock+0x5c/0x8a8
[  614.363348]  mutex_lock_nested+0x1c/0x28
[  614.375654]  axienet_dma_err_handler+0x38/0x388
[  614.389999]  tasklet_action_common.isra.15+0x160/0x1a8
[  614.405894]  tasklet_action+0x24/0x30
[  614.417297]  efi_header_end+0xe0/0x494
[  614.429020]  irq_exit+0xd0/0xd8
[  614.439047]  __handle_domain_irq+0x60/0xb0
[  614.451877]  gic_handle_irq+0xdc/0x2d0
[  614.463486]  el1_irq+0xcc/0x180
[  614.473451]  __tcp_transmit_skb+0x41c/0xb58
[  614.486513]  tcp_write_xmit+0x224/0x10a0
[  614.498792]  __tcp_push_pending_frames+0x38/0xc8
[  614.513126]  tcp_rcv_established+0x41c/0x820
[  614.526301]  tcp_v4_do_rcv+0x8c/0x218
[  614.537784]  __release_sock+0x5c/0x108
[  614.549466]  release_sock+0x34/0xa0
[  614.560318]  tcp_sendmsg+0x40/0x58
[  614.571053]  inet_sendmsg+0x40/0x68
[  614.582061]  sock_sendmsg+0x18/0x30
[  614.593074]  xs_sendpages+0x218/0x328
[  614.604506]  xs_tcp_send_request+0xa0/0x1b8
[  614.617461]  xprt_transmit+0xc8/0x4f0
[  614.628943]  call_transmit+0x8c/0xa0
[  614.640028]  __rpc_execute+0xbc/0x6f8
[  614.651380]  rpc_async_schedule+0x28/0x48
[  614.663846]  process_one_work+0x298/0x6a8
[  614.676299]  worker_thread+0x40/0x490
[  614.687687]  kthread+0x134/0x138
[  614.697804]  ret_from_fork+0x10/0x18
[  614.717319] xilinx_axienet 7fe00000.ethernet eth0: Link is Down
[  615.748343] xilinx_axienet 7fe00000.ethernet eth0: Link is Up - 1Gbps/Full - flow control off

Since tasklets are not really popular anymore anyway, lets convert this
over to a work queue, which can sleep and thus can take the MDIO mutex.
Signed-off-by: NAndre Przywara <andre.przywara@arm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Set ethtool_ops->supported_coalesce_params to let
the core reject unsupported coalescing parameters.

This driver already correctly rejected all unsupported
parameters. No functional changes.
Signed-off-by: NJakub Kicinski <kuba@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Convert the Xilinx AXI ethernet driver to use the finalised link
parameters in mac_link_up() rather than the parameters in mac_config().
Tested-by: NAndre Przywara <andre.przywara@arm.com>
Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Propagate the resolved link parameters via the mac_link_up() call for
MACs that do not automatically track their PCS state. We propagate the
link parameters via function arguments so that inappropriate members
of struct phylink_link_state can't be accessed, and creating a new
structure just for this adds needless complexity to the API.
Tested-by: NAndre Przywara <andre.przywara@arm.com>
Tested-by: NAlexandre Belloni <alexandre.belloni@bootlin.com>
Tested-by: NVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Rename the mac_link_state() method to mac_pcs_get_state() to make it
clear that it should be returning the MACs PCS current state, which
is used for inband negotiation rather than just reading back what the
MAC has been configured for. Update the documentation to explicitly
mention that this is for inband.

We drop the return value as well; most of phylink doesn't check the
return value and it is not clear what it should do on error - instead
arrange for state->link to be false.
Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: NJakub Kicinski <jakub.kicinski@netronome.com>

In the DMA memory resource get failed case, the error is not
set and 0 will be returned. Fix it by removing redundant check
since devm_ioremap_resource() will handle it.

Fixes: 28ef9ebd ("net: axienet: make use of axistream-connected attribute optional")
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: NRadhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Before this change of_get_phy_mode() returned an enum,
phy_interface_t. On error, -ENODEV etc, is returned. If the result of
the function is stored in a variable of type phy_interface_t, and the
compiler has decided to represent this as an unsigned int, comparision
with -ENODEV etc, is a signed vs unsigned comparision.

Fix this problem by changing the API. Make the function return an
error, or 0 on success, and pass a pointer, of type phy_interface_t,
where the phy mode should be stored.

v2:
Return with *interface set to PHY_INTERFACE_MODE_NA on error.
Add error checks to all users of of_get_phy_mode()
Fixup a few reverse christmas tree errors
Fixup a few slightly malformed reverse christmas trees

v3:
Fix 0-day reported errors.
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The "lp->phy_mode" is an enum but in this context GCC treats it as an
unsigned int so the error handling is never triggered.

Fixes: ee06b172 ("net: axienet: add support for standard phy-mode binding")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: NRadhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

There is a possible use-after-free issue in the axienet_probe():

1701:	np = of_parse_phandle(pdev->dev.of_node, "axistream-connected", 0);
1702:   if (np) {
...
1787:		of_node_put(np); ---> released here
1788:		lp->eth_irq = platform_get_irq(pdev, 0);
1789:	} else {
...
1801:	}
1802:	if (IS_ERR(lp->dma_regs)) {
...
1805:		of_node_put(np); ---> double released here
1806:		goto free_netdev;
1807:	}

We solve this problem by removing the unnecessary of_node_put().

Fixes: 28ef9ebd ("net: axienet: make use of axistream-connected attribute optional")
Signed-off-by: NWen Yang <wen.yang99@zte.com.cn>
Cc: Anirudha Sarangi <anirudh@xilinx.com>
Cc: John Linn <John.Linn@xilinx.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: Robert Hancock <hancock@sedsystems.ca>
Cc: netdev@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: NRobert Hancock <hancock@sedsystems.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We were accessing the pointer returned from platform_get_resource before
checking if it was valid, causing an oops if it was not. Move this access
after the call to devm_ioremap_resource which does the validity check.
Signed-off-by: NRobert Hancock <hancock@sedsystems.ca>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Convert this driver to use the phylink API rather than the legacy PHY
API. This allows for better support for SFP modules connected using a
1000BaseX or SGMII interface.
Signed-off-by: NRobert Hancock <hancock@sedsystems.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Currently the axienet driver requires the use of a second devicetree
node, referenced by an axistream-connected attribute on the Ethernet
device node, which contains the resources for the AXI DMA block used by the
device. This setup is problematic for a use case we have where the Ethernet
and DMA cores are behind a PCIe to AXI bridge and the memory resources for
the nodes are injected into the platform devices using the multifunction
device subsystem - it's not easily possible for the driver to obtain the
platform-level resources from the linked device.

In order to simplify that usage model, and simplify the overall use of
this driver in general, allow for all of the resources to be kept on one
node where the resources are retrieved using platform device APIs rather
than device-tree-specific ones. The previous usage setup is still
supported if the axistream-connected attribute is specified.
Signed-off-by: NRobert Hancock <hancock@sedsystems.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

On some platforms, such as iMX6 with PCIe devices, crashes or hangs can
occur if the axienet device continues to perform DMA transfers after
parent devices/busses have been shut down. Shut down the axienet
interface during its shutdown callback in order to avoid this.
Signed-off-by: NRobert Hancock <hancock@sedsystems.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Failing initialization on a missing MAC address property is excessive.
We can just fall back to using a random MAC instead, which at least
leaves the interface in a functioning state.
Signed-off-by: NRobert Hancock <hancock@sedsystems.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

It is possible that the interrupt handler fires and frees up space in
the TX ring in between checking for sufficient TX ring space and
stopping the TX queue in axienet_start_xmit. If this happens, the
queue wake from the interrupt handler will occur before the queue is
stopped, causing a lost wakeup and the adapter's transmit hanging.

To avoid this, after stopping the queue, check again whether there is
sufficient space in the TX ring. If so, wake up the queue again.
Signed-off-by: NRobert Hancock <hancock@sedsystems.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Previously this driver only handled interrupts from the DMA RX and TX
blocks, not from the Ethernet core itself. Add optional support for
the Ethernet core interrupt, which is used to detect rx_missed and
framing errors signalled by the hardware. In order to use this
interrupt, a third interrupt needs to be specified in the device tree.
Signed-off-by: NRobert Hancock <hancock@sedsystems.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Specify IRQF_SHARED to support shared interrupts. If the interrupt
handler is called and the device is not indicating an interrupt,
just return IRQ_NONE rather than spewing error messages.
Signed-off-by: NRobert Hancock <hancock@sedsystems.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

These registers are important for troubleshooting the state of the DMA
cores.
Signed-off-by: NRobert Hancock <hancock@sedsystems.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add support for setting the RX and TX ring sizes for this driver using
ethtool. Also increase the default RX ring size as the previous default
was far too low for good performance in some configurations.
Signed-off-by: NRobert Hancock <hancock@sedsystems.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The Xilinx DMA blocks each have their own reset register, but they both
reset the entire DMA engine, so only one of them needs to be reset.

Also, when stopping the device, we need to not just command the DMA
blocks to stop, but wait for them to stop, and trigger a device reset
to ensure that they are completely stopped.
Signed-off-by: NRobert Hancock <hancock@sedsystems.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The MDIO clock divisor register setting was only applied on the initial
startup when the driver was loaded. However, this setting is cleared
when the device is reset, such as would occur when the interface was
taken down and brought up again, and so the MDIO bus would be
non-functional afterwards.

Split up the MDIO bus setup and enable into separate functions and
re-enable the bus after a device reset, to ensure that the MDIO
registers are set properly. This also allows us to remove direct access
to MDIO registers in xilinx_axienet_main.c and centralize them all in
xilinx_axienet_mdio.c.

Also, lock the MDIO bus lock around the device reset process, to avoid
MDIO accesses from occurring while the MDIO is disabled during the reset.
Signed-off-by: NRobert Hancock <hancock@sedsystems.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Since the MDIO is is brought up before the netdev is registered, it
should be torn down after the netdev is removed. Otherwise, PHY accesses
can potentially access freed MDIO bus references and cause a crash.
Signed-off-by: NRobert Hancock <hancock@sedsystems.ca>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This driver was previously always calculating the MDIO clock divisor
(from AXI bus clock to MDIO bus clock) based on the CPU clock frequency,
assuming that it is the same as the AXI bus frequency, but that
simplistic method only works on the MicroBlaze platform.

Add support for specifying the clock used for the device in the device
tree using the clock framework. If the clock is specified then it will
be used when calculating the clock divisor. The previous CPU clock
detection method is left for backward compatibility if no clock is
specified.
Signed-off-by: NRobert Hancock <hancock@sedsystems.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The MDIO bus for this driver was being named using the result of
of_address_to_resource on a node which may not have any resource on it,
but the return value of that call was not checked so it was using some
random value in the bus name. Change to name the MDIO bus based on the
resource start of the actual Ethernet register block.
Signed-off-by: NRobert Hancock <hancock@sedsystems.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This driver was using in_be32 and out_be32 IO accessors which do not
exist on most platforms. Also, the use of big-endian accessors does not
seem correct as this hardware is accessed over an AXI bus which, to the
extent it has an endian-ness, is little-endian. Switch to standard
ioread32/iowrite32 accessors.
Signed-off-by: NRobert Hancock <hancock@sedsystems.ca>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This driver was casting skb pointers to u32 and storing them as such in
the DMA buffer descriptor, which is obviously broken on 64-bit. The area
of the buffer descriptor being used is not accessed by the hardware and
has sufficient room for a 32 or 64-bit pointer, so just store the skb
pointer as such.
Signed-off-by: NRobert Hancock <hancock@sedsystems.ca>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have MODULE_LICENCE("GPL*") inside which was used in the initial
   scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

There was NVMEM support added to of_get_mac_address, so it could now
return ERR_PTR encoded error values, so we need to adjust all current
users of of_get_mac_address to this new fact.

While at it, remove superfluous is_valid_ether_addr as the MAC address
returned from of_get_mac_address is always valid and checked by
is_valid_ether_addr anyway.

Fixes: d01f449c ("of_net: add NVMEM support to of_get_mac_address")
Signed-off-by: NPetr Štetiar <ynezz@true.cz>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The call to of_parse_phandle returns a node pointer with refcount
incremented thus it must be explicitly decremented after the last
usage.

Detected by coccinelle with the following warnings:
./drivers/net/ethernet/xilinx/xilinx_axienet_main.c:1624:1-7: ERROR: missing of_node_put; acquired a node pointer with refcount incremented on line 1569, but without a corresponding object release within this function.
Signed-off-by: NWen Yang <wen.yang99@zte.com.cn>
Cc: Anirudha Sarangi <anirudh@xilinx.com>
Cc: John Linn <John.Linn@xilinx.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Michal Simek <michal.simek@xilinx.com>
Cc: netdev@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: NDavid S. Miller <davem@davemloft.net>