net: axienet: Introduce dmaengine support

Add dmaengine framework to communicate with the xilinx DMAengine
driver(AXIDMA).

Axi ethernet driver uses separate channels for transmit and receive.
Add support for these channels to handle TX and RX with skb and
appropriate callbacks. Also add axi ethernet core interrupt for
dmaengine framework support.

The dmaengine framework was extended for metadata API support.
However it still needs further enhancements to make it well suited for
ethernet usecases. The ethernet features i.e ethtool set/get of DMA IP
properties, ndo_poll_controller,(mentioned in TODO) are not supported
and it requires follow-up discussions.

dmaengine support has a dependency on xilinx_dma as it uses
xilinx_vdma_channel_set_config() API to reset the DMA IP
which internally reset MAC prior to accessing MDIO.

Benchmark with netperf:

xilinx-zcu102-20232:~$ netperf -H 192.168.10.20 -t TCP_STREAM
MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET
to 192.168.10.20 () port 0 AF_INET
Recv Send Send
Socket Socket Message Elapsed
Size Size Size Time Throughput
bytes bytes bytes secs. 10^6bits/sec

131072 16384 16384 10.02 886.69

xilinx-zcu102-20232:~$ netperf -H 192.168.10.20 -t UDP_STREAM
MIGRATED UDP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET
to 192.168.10.20 () port 0 AF_INET
Socket Message Elapsed Messages
Size Size Time Okay Errors Throughput
bytes bytes secs # # 10^6bits/sec

212992 65507 10.00 15851 0 830.66
212992 10.00 15851 830.66

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
Link: https://lore.kernel.org/r/1700074613-1977070-4-git-send-email-radhey.shyam.pandey@amd.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: axienet: Preparatory changes for dmaengine support

The axiethernet driver has inbuilt dma programming. In order to add
dmaengine support and make it's integration seamless the current axidma
inbuilt programming code is put under use_dmaengine check.

It also performs minor code reordering to minimize conditional
use_dmaengine checks and there is no functional change. It uses
"dmas" property to identify whether it should use a dmaengine
framework or inbuilt axidma programming.

Signed-off-by: Sarath Babu Naidu Gaddam <sarath.babu.naidu.gaddam@amd.com>
Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
Link: https://lore.kernel.org/r/1700074613-1977070-3-git-send-email-radhey.shyam.pandey@amd.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: axienet: Unexport and remove unused mdio functions

Both axienet_mdio_{enable/disable} functions are no longer used in
xilinx_axienet_main.c due to 253761a0e61b7. And axienet_mdio_disable is
not even used in the mdio.c. So unexport and remove them.

Signed-off-by: Andy Chiu <andy.chiu@sifive.com>
Reviewed-by: Greentime Hu <greentime.hu@sifive.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ll_temac: axienet: align with open parenthesis

Cleaning some static warnings of open parenthesis.

Signed-off-by: huangjunxian <huangjunxian6@hisilicon.com>
Signed-off-by: Haoyue Xu <xuhaoyue1@hisilicon.com>
Reviewed-by: Harini Katakam <harini.katakam@amd.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: axienet: Switch to 64-bit RX/TX statistics

The RX and TX byte/packet statistics in this driver could be overflowed
relatively quickly on a 32-bit platform. Switch these stats to use the
u64_stats infrastructure to avoid this.

Signed-off-by: Robert Hancock <robert.hancock@calian.com>
Link: https://lore.kernel.org/r/20220829233901.3429419-1-robert.hancock@calian.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

xilinx: Fix build on x86.

CONFIG_64BIT is not sufficient for checking for availability of
iowrite64() and friends.

Also, the out_addr helpers need to be inline.

Fixes: b690f8df6497 ("net: axienet: Use iowrite64 to write all 64b descriptor pointers")
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: Use iowrite64 to write all 64b descriptor pointers

According to commit f735c40ed93c ("net: axienet: Autodetect 64-bit DMA
capability") and AXI-DMA spec (pg021), on 64-bit capable dma, only
writing MSB part of tail descriptor pointer causes DMA engine to start
fetching descriptors. However, we found that it is true only if dma is in
idle state. In other words, dma would use a tailp even if it only has LSB
updated, when the dma is running.

The non-atomicity of this behavior could be problematic if enough
delay were introduced in between the 2 writes. For example, if an
interrupt comes right after the LSB write and the cpu spends long
enough time in the handler for the dma to get back into idle state by
completing descriptors, then the seconcd write to MSB would treat dma
to start fetching descriptors again. Since the descriptor next to the
one pointed by current tail pointer is not filled by the kernel yet,
fetching a null descriptor here causes a dma internal error and halt
the dma engine down.

We suggest that the dma engine should start process a 64-bit MMIO write
to the descriptor pointer only if ONE 32-bit part of it is written on all
states. Or we should restrict the use of 64-bit addressable dma on 32-bit
platforms, since those devices have no instruction to guarantee the write
to LSB and MSB part of tail pointer occurs atomically to the dma.

initial condition:
curp = x-3;
tailp = x-2;
LSB = x;
MSB = 0;

cpu: |dma:
iowrite32(LSB, tailp) | completes #(x-3) desc, curp = x-3
... | tailp updated
=> irq | completes #(x-2) desc, curp = x-2
... | completes #(x-1) desc, curp = x-1
... | ...
... | completes #x desc, curp = tailp = x
<= irqreturn | reaches tailp == curp = x, idle
iowrite32(MSB, tailp + 4) | ...
| tailp updated, starts fetching...
| fetches #(x + 1) desc, sees cntrl = 0
| post Tx error, halt

Signed-off-by: Andy Chiu <andy.chiu@sifive.com>
Reported-by: Max Hsu <max.hsu@sifive.com>
Reviewed-by: Greentime Hu <greentime.hu@sifive.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: make the 64b addresable DMA depends on 64b archectures

Currently it is not safe to config the IP as 64-bit addressable on 32-bit
archectures, which cannot perform a double-word store on its descriptor
pointers. The pointer is 64-bit wide if the IP is configured as 64-bit,
and the device would process the partially updated pointer on some
states if the pointer was updated via two store-words. To prevent such
condition, we force a probe fail if we discover that the IP has 64-bit
capability but it is not running on a 64-Bit kernel.

This is a series of patch (1/2). The next patch must be applied in order
to make 64b DMA safe on 64b archectures.

Signed-off-by: Andy Chiu <andy.chiu@sifive.com>
Reported-by: Max Hsu <max.hsu@sifive.com>
Reviewed-by: Greentime Hu <greentime.hu@sifive.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: Use NAPI for TX completion path

This driver was using the TX IRQ handler to perform all TX completion
tasks. Under heavy TX network load, this can cause significant irqs-off
latencies (found to be in the hundreds of microseconds using ftrace).
This can cause other issues, such as overrunning serial UART FIFOs when
using high baud rates with limited UART FIFO sizes.

Switch to using a NAPI poll handler to perform the TX completion work
to get this out of hard IRQ context and avoid the IRQ latency impact.
A separate poll handler is used for TX and RX since they have separate
IRQs on this controller, so that the completion work for each of them
stays on the same CPU as the interrupt.

Testing on a Xilinx MPSoC ZU9EG platform using iperf3 from a Linux PC
through a switch at 1G link speed showed no significant change in TX or
RX throughput, with approximately 941 Mbps before and after. Hard IRQ
time in the TX throughput test was significantly reduced from 12% to
below 1% on the CPU handling TX interrupts, with total hard+soft IRQ CPU
usage dropping from about 56% down to 48%.

Signed-off-by: Robert Hancock <robert.hancock@calian.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: factor out phy_node in struct axienet_local

the struct member `phy_node` of struct axienet_local is not used by the
driver anymore after initialization. It might be a remnent of old code
and could be removed.

Signed-off-by: Andy Chiu <andy.chiu@sifive.com>
Reviewed-by: Greentime Hu <greentime.hu@sifive.com>
Reviewed-by: Robert Hancock <robert.hancock@calian.com>
Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: add coalesce timer ethtool configuration

Add the ability to configure the RX/TX coalesce timer with ethtool.
Change default setting to scale with the clock rate rather than being a
fixed number of clock cycles.

Signed-off-by: Robert Hancock <robert.hancock@calian.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: reduce default RX interrupt threshold to 1

Now that NAPI has been implemented, the hardware interrupt mitigation
mechanism is not needed to avoid excessive interrupt load in most cases.
Reduce the default RX interrupt threshold to 1 to reduce introduced
latency. This can be increased with ethtool if desired if some applications
still want to reduce interrupts.

Signed-off-by: Robert Hancock <robert.hancock@calian.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: implement NAPI and GRO receive

Implement NAPI and GRO receive. In addition to better performance, this
also avoids handling RX packets in hard IRQ context, which reduces the
IRQ latency impact to other devices.

Signed-off-by: Robert Hancock <robert.hancock@calian.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: convert to phylink_pcs

Convert axienet to use the phylink_pcs layer, resulting in it no longer
being a legacy driver.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: Enable more clocks

This driver was only enabling the first clock on the device, regardless
of its name. However, this controller logic can have multiple clocks
which should all be enabled. Add support for enabling additional clocks.
The clock names used are matching those used in the Xilinx version of this
driver as well as the Xilinx device tree generator, except for mgt_clk
which is not present there.

For backward compatibility, if no named clocks are present, the first
clock present is used for determining the MDIO bus clock divider.

Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: Robert Hancock <robert.hancock@calian.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: allow setups without MDIO

In setups with fixed-link settings there is no mdio node in DTS.
axienet_probe() already handles that gracefully but lp->mii_bus is
then NULL.

Fix code that tries to blindly grab the MDIO lock by introducing two helper
functions that make the locking conditional.

Signed-off-by: Daniel Mack <daniel@zonque.org>
Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: Support dynamic switching between 1000BaseX and SGMII

Newer versions of the Xilinx AXI Ethernet core (specifically version 7.2 or
later) allow the core to be configured with a PHY interface mode of "Both",
allowing either 1000BaseX or SGMII modes to be selected at runtime. Add
support for this in the driver to allow better support for applications
which can use both fiber and copper SFP modules.

Signed-off-by: Robert Hancock <robert.hancock@calian.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: xilinx: axiethernet: Introduce helper functions for MDC enable/disable

Introduce helper functions to enable/disable MDIO interface clock. This
change serves a preparatory patch for the coming feature to dynamically
control the management bus clock.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: axienet: Properly handle PCS/PMA PHY for 1000BaseX mode

Update the axienet driver to properly support the Xilinx PCS/PMA PHY
component which is used for 1000BaseX and SGMII modes, including
properly configuring the auto-negotiation mode of the PHY and reading
the negotiated state from the PHY.

Signed-off-by: Robert Hancock <robert.hancock@calian.com>
Reviewed-by: Radhey Shyam Pandey <radhey.shyam.pandey@xilinx.com>
Link: https://lore.kernel.org/r/20201028171429.1699922-1-robert.hancock@calian.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: axienet: fix spelling mistake in comment "Exteneded" -> "extended"

There is a spelling mistake in a comment. Fix it.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: Autodetect 64-bit DMA capability

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: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: Upgrade descriptors to hold 64-bit addresses

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: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: Drop MDIO interrupt registers from ethtools dump

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: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: Convert DMA error handler to a work queue

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: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: convert to phylink API

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: Robert Hancock <hancock@sedsystems.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: Add optional support for Ethernet core interrupt

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: Robert Hancock <hancock@sedsystems.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: Make RX/TX ring sizes configurable

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: Robert Hancock <hancock@sedsystems.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: Cleanup DMA device reset and halt process

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: Robert Hancock <hancock@sedsystems.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: Re-initialize MDIO registers properly after reset

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: Robert Hancock <hancock@sedsystems.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: Use clock framework to get device clock rate

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: Robert Hancock <hancock@sedsystems.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: fix MDIO bus naming

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: Robert Hancock <hancock@sedsystems.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: Use standard IO accessors

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: Robert Hancock <hancock@sedsystems.ca>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: Fix casting of pointers to u32

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: Robert Hancock <hancock@sedsystems.ca>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

1/2] net: axienet: use readx_poll_timeout() in mdio wait function

On loaded systems with a preemptible kernel the mdio_wait() function may
report an error while everything is working fine:

axienet_mdio_wait_until_ready():
axienet_ior() -> chip not ready
--> interrupt here (other work for some time / chip become ready)
if (time_before_eq(end, jiffies))
--> false positive error report

Replace the current code with readx_poll_timeout() which take care
of the situation.

Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
Signed-off-by: Benedikt Spranger <b.spranger@linutronix.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.

For non */uapi/* files that summary was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139

and resulted in the first patch in this series.

If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:

SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930

and resulted in the second patch in this series.

- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:

SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1

and that resulted in the third patch in this series.

- when the two scanners agreed on the detected license(s), that became
the concluded license(s).

- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.

- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).

- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.

- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct

This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

net: axienet: add support for standard phy-mode binding

Keep supporting proprietary "xlnx,phy-type" attribute and add support for
MII connectivity to the PHY.

Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Alvaro Gamez Machado <alvaro.gamez@hazent.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: ethernet: xilinx: axienet: use phydev from struct net_device

The private structure contain a pointer to phydev, but the structure
net_device already contain such pointer. So we can remove the pointer
phy in the private structure, and update the driver to use the
one contained in struct net_device.

Signed-off-by: Philippe Reynes <tremyfr@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mdio: Move allocation of interrupts into core

Have mdio_alloc() create the array of interrupt numbers, and
initialize it to POLLING. This is what most MDIO drivers want, so
allowing code to be removed from the drivers.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: Fix kernel-doc warnings

This patch remove kernel-doc warnings.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: Fix comments blocks

There is rule for network drivers with comments blocks
which is newly checked by checkpatch.pl script.
Let's fix it.

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: axienet: Handle jumbo frames for lesser frame sizes

In the current implementation, jumbo frames are supported only
for the frame sizes > 16K. This patch corrects this logic to
handle jumbo frames for lesser frame sizes (< 16K) ensuring jumbo frame
MTU is within the limit of max frame size configured in the h/w
design.

Signed-off-by: Srikanth Thokala <sthokal@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: xilinx: Remove unnecessary temac_property in the driver

This property is no longer used in the code yet the code looks for it in the device tree.
It does not cause an error if it's not in the tree.

Signed-off-by: Kedareswara rao Appana <appanad@xilinx.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/xilinx/axi ethernet: Correct Copyright

Also fix MAINTAINERS file to reflect autorship.

Daniel and Ariane changed coding style but not any functional changes in the driver
itself.

Signed-off-by: Michal Simek <monstr@monstr.eu>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/xilinx: added Xilinx AXI Ethernet driver

This driver adds support for Xilinx 10/100/1000 AXI Ethernet.

It can be used, for instance, on Xilinx boards with a Microblaze
architecture like the ML605.

The patch is against the latest net-next tree and checkpatch clean.

Signed-off-by: Ariane Keller <ariane.keller@tik.ee.ethz.ch>
Signed-off-by: Daniel Borkmann <daniel.borkmann@tik.ee.ethz.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>