drivers/net/ethernet/atheros/atlx/atl2.c:40:19: warning: ‘atl2_driver_string’ defined but not used [-Wunused-const-variable=]
 static const char atl2_driver_string[] = "Atheros(R) L2 Ethernet Driver";
                   ^~~~~~~~~~~~~~~~~~

commit ea973742 ("net/atheros: Clean atheros code from driver version")
left behind this, remove it.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In the commit f73b1281
("tipc: improve throughput between nodes in netns"), we're missing a check
to handle TIPC_DIRECT_MSG type, it's still using old sending mechanism for
this message type. So, throughput improvement is not significant as
expected.

Besides that, when sending a large message with that type, we're also
handle wrong receiving queue, it should be enqueued in socket receiving
instead of multicast messages.

Fix this by adding the missing case for TIPC_DIRECT_MSG.

Fixes: f73b1281 ("tipc: improve throughput between nodes in netns")
Reported-by: Tuong Lien <tuong.t.lien@dektech.com.au>
Signed-off-by: Hoang Le <hoang.h.le@dektech.com.au>
Acked-by: Jon Maloy <jmaloy@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Overlapping header include additions in macsec.c

A bug fix in 'net' overlapping with the removal of 'version'
string in ena_netdev.c

Overlapping test additions in selftests Makefile

Overlapping PCI ID table adjustments in iwlwifi driver.
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull networking fixes from David Miller:

 1) Fix deadlock in bpf_send_signal() from Yonghong Song.

 2) Fix off by one in kTLS offload of mlx5, from Tariq Toukan.

 3) Add missing locking in iwlwifi mvm code, from Avraham Stern.

 4) Fix MSG_WAITALL handling in rxrpc, from David Howells.

 5) Need to hold RTNL mutex in tcindex_partial_destroy_work(), from Cong
    Wang.

 6) Fix producer race condition in AF_PACKET, from Willem de Bruijn.

 7) cls_route removes the wrong filter during change operations, from
    Cong Wang.

 8) Reject unrecognized request flags in ethtool netlink code, from
    Michal Kubecek.

 9) Need to keep MAC in reset until PHY is up in bcmgenet driver, from
    Doug Berger.

10) Don't leak ct zone template in act_ct during replace, from Paul
    Blakey.

11) Fix flushing of offloaded netfilter flowtable flows, also from Paul
    Blakey.

12) Fix throughput drop during tx backpressure in cxgb4, from Rahul
    Lakkireddy.

13) Don't let a non-NULL skb->dev leave the TCP stack, from Eric
    Dumazet.

14) TCP_QUEUE_SEQ socket option has to update tp->copied_seq as well,
    also from Eric Dumazet.

15) Restrict macsec to ethernet devices, from Willem de Bruijn.

16) Fix reference leak in some ethtool *_SET handlers, from Michal
    Kubecek.

17) Fix accidental disabling of MSI for some r8169 chips, from Heiner
    Kallweit.

* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (138 commits)
  net: Fix CONFIG_NET_CLS_ACT=n and CONFIG_NFT_FWD_NETDEV={y, m} build
  net: ena: Add PCI shutdown handler to allow safe kexec
  selftests/net/forwarding: define libs as TEST_PROGS_EXTENDED
  selftests/net: add missing tests to Makefile
  r8169: re-enable MSI on RTL8168c
  net: phy: mdio-bcm-unimac: Fix clock handling
  cxgb4/ptp: pass the sign of offset delta in FW CMD
  net: dsa: tag_8021q: replace dsa_8021q_remove_header with __skb_vlan_pop
  net: cbs: Fix software cbs to consider packet sending time
  net/mlx5e: Do not recover from a non-fatal syndrome
  net/mlx5e: Fix ICOSQ recovery flow with Striding RQ
  net/mlx5e: Fix missing reset of SW metadata in Striding RQ reset
  net/mlx5e: Enhance ICOSQ WQE info fields
  net/mlx5_core: Set IB capability mask1 to fix ib_srpt connection failure
  selftests: netfilter: add nfqueue test case
  netfilter: nft_fwd_netdev: allow to redirect to ifb via ingress
  netfilter: nft_fwd_netdev: validate family and chain type
  netfilter: nft_set_rbtree: Detect partial overlaps on insertion
  netfilter: nft_set_rbtree: Introduce and use nft_rbtree_interval_start()
  netfilter: nft_set_pipapo: Separate partial and complete overlap cases on insertion
  ...

Pull GPIO fixes from Linus Walleij:

 - One core quirk by myself to fix the .irq_disable() semantics when the
   gpiolib core takes over this callback.

 - The rest is an elaborate series of four patches fixing Intel laptop
   ACPI wakeup quirks.

* tag 'gpio-v5.6-3' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-gpio:
  gpiolib: acpi: Add quirk to ignore EC wakeups on HP x2 10 CHT + AXP288 model
  gpiolib: acpi: Add quirk to ignore EC wakeups on HP x2 10 BYT + AXP288 model
  gpiolib: acpi: Rework honor_wakeup option into an ignore_wake option
  gpiolib: acpi: Correct comment for HP x2 10 honor_wakeup quirk
  gpiolib: Fix irq_disable() semantics

Merge tag 'wireless-drivers-2020-03-25' of git://git.kernel.org/pub/scm/linux/kernel/git/kvalo/wireless-drivers

Kalle Valo says:

====================
wireless-drivers fixes for v5.6

Fourth, and last, set of fixes for v5.6. Just two important fixes to
iwlwifi regressions.

iwlwifi

* fix GEO_TX_POWER_LIMIT command on certain devices which caused
  firmware to crash during initialisation

* add back device ids for three devices which were accidentally
  removed
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

net/netfilter/nft_fwd_netdev.c: In function ‘nft_fwd_netdev_eval’:
    net/netfilter/nft_fwd_netdev.c:32:10: error: ‘struct sk_buff’ has no member named ‘tc_redirected’
      pkt->skb->tc_redirected = 1;
              ^~
    net/netfilter/nft_fwd_netdev.c:33:10: error: ‘struct sk_buff’ has no member named ‘tc_from_ingress’
      pkt->skb->tc_from_ingress = 1;
              ^~

To avoid a direct dependency with tc actions from netfilter, wrap the
redirect bits around CONFIG_NET_REDIRECT and move helpers to
include/linux/skbuff.h. Turn on this toggle from the ifb driver, the
only existing client of these bits in the tree.

This patch adds skb_set_redirected() that sets on the redirected bit
on the skbuff, it specifies if the packet was redirect from ingress
and resets the timestamp (timestamp reset was originally missing in the
netfilter bugfix).

Fixes: bcfabee1 ("netfilter: nft_fwd_netdev: allow to redirect to ifb via ingress")
Reported-by: noreply@ellerman.id.au
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

This commit adds support to catch any bits set in SGE_INT_CAUSE5 for Parity Errors.
F_ERR_T_RXCRC flag is used to ignore that particular bit as it is not considered as fatal.
So, we clear out the bit before looking for error.
This patch now read and report separately all three registers(Cause1, Cause2, Cause5).
Also, checks for errors if any.
Signed-off-by: Raju Rangoju <rajur@chelsio.com>
Signed-off-by: Rahul Kundu <rahul.kundu@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Sunil Goutham says:

====================
octeontx2-pf: Miscellaneous fixes

This patchset fixes couple of issues related to missing
page refcount updation and taking a mutex lock in atomic
context.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Since set_rx_mode takes a mutex lock for sending mailbox
message to admin function to set the mode, moved logic
to a workqueue.
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fixed an issue wherein while refilling receive buffers
for the last page allocated, recount is not being updated.
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Julian Wiedmann says:

====================
s390/qeth: updates 2020-03-25

please apply the following patch series for qeth to netdev's net-next
tree.
Same series as yesterday, with one minor update to patch 1 as per
your review.

This adds
1) NAPI poll support for the async-Completion Queue (with one qdio layer
   patch acked by Heiko),
2) ethtool support for per-queue TX IRQ coalescing,
3) various cleanups.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Replace list_for_each() with list_for_each_entry(), and
list_entry(head.next) with list_first_entry().
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When a device is configured in prio-queue mode to pin all traffic onto
a specific HW queue, treat this as a distinct variant of prio-queueing
instead of QETH_NO_PRIO_QUEUEING.

This corrects an error message from qeth_osa_set_output_queues() for
devices configured in such a mode.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Return the correct errnos when .ndo_set_mac_address fails to set a new
MAC address.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Since IQD devices complete (most of) their transmissions synchronously,
they don't offer TX completion IRQs and have no HW coalescing controls.
But we can fake the easy parts in SW, and give the user some control wrt
to how often the TX NAPI code should be triggered to process the TX
completions.

Having per-queue controls can in particular help the dedicated mcast
queue, as it likely benefits from different fine-tuning than what the
ucast queues need.

CC: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Count the number of TX doorbells we issue to the qdio layer.

Also count the number of actual frames in a TX buffer, and then
use this data along with the byte count during TX completion.
We'll make additional use of the frame count in a subsequent patch.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

We're down to a single bit flag for MAC-address related status, reflect
that in the info struct.
Also set up the flag during initialization instead of clearing it during
shutdown - one more little step towards unifying the shutdown code.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The logic that deals with errors from qeth_l3_get_unique_id() is quite
complex: it sets card->unique_id to 0xfffe, additionally flags it as
UNIQUE_ID_NOT_BY_CARD and later takes this flag as cue to not propagate
card->unique_id to dev->dev_id. With dev->dev_id thus holding 0,
addrconf_ifid_eui48() applies its default behaviour.

Get rid of all the special bit masks, and just return the old uid in
case of an error. For the vast majority of cases this will be 0 (and so
we still get the desired default behaviour) - with the rare exception
where qeth_l3_get_unique_id() might have been called earlier but the
initialization then failed at a later point.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

When the support for polling drivers was initially added, it only
considered Input Queue 0. But as QDIO interrupts are actually for the
full device and not a single queue, this doesn't really fit for
configurations where multiple Input Queues are used.

Rework the qdio code so that interrupts for a polling driver are not
split up into actions for each queue. Instead deliver the interrupt as
a single event, and let the driver decide which queue needs what action.

When re-enabling the QDIO interrupt via qdio_start_irq(), this means
that the qdio code needs to
(1) put _all_ eligible queues back into a state where they raise IRQs,
(2) and afterwards check _all_ eligible queues for new work to bridge
    the race window.

On the qeth side of things (as the only qdio polling driver), we can now
add CQ polling support to the main NAPI poll routine. It doesn't consume
NAPI budget, and to avoid hogging the CPU we yield control after
completing one full queue worth of buffers.
The subsequent qdio_start_irq() will check for any additional work, and
have us re-schedule the NAPI instance accordingly.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Acked-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Whenever all completed RX buffers have been processed
(ie. rx->b_count == 0), we call down to the HW layer to scan for
additional buffers. If no further buffers are available, the code
breaks out of the while-loop.

So we never reach the 'process an RX buffer' step with rx->b_count == 0,
eliminate that check and one level of indentation.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The main NAPI poll routine should eventually handle more types of work,
beyond just the RX ring.
Split off the RX poll logic into a separate function, and simplify the
nested while-loop.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Since RX buffers may contain multiple packets, qeth's NAPI poll code can
exhaust its budget in the middle of an RX buffer. Thus we keep track of
our current position within the active RX buffer, so we can resume
processing here in the next NAPI poll period.

Clean up that code by tracking the index of the active buffer element,
instead of a pointer to it.
Also simplify the code that advances to the next RX buffer when the
current buffer has been fully processed.

v2: - remove QDIO_ELEMENT_NO() macro (davem)
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Currently ENA only provides the PCI remove() handler, used during rmmod
for example. This is not called on shutdown/kexec path; we are potentially
creating a failure scenario on kexec:

(a) Kexec is triggered, no shutdown() / remove() handler is called for ENA;
instead pci_device_shutdown() clears the master bit of the PCI device,
stopping all DMA transactions;

(b) Kexec reboot happens and the device gets enabled again, likely having
its FW with that DMA transaction buffered; then it may trigger the (now
invalid) memory operation in the new kernel, corrupting kernel memory area.

This patch aims to prevent this, by implementing a shutdown() handler
quite similar to the remove() one - the difference being the handling
of the netdev, which is unregistered on remove(), but following the
convention observed in other drivers, it's only detached on shutdown().

This prevents an odd issue in AWS Nitro instances, in which after the 2nd
kexec the next one will fail with an initrd corruption, caused by a wild
DMA write to invalid kernel memory. The lspci output for the adapter
present in my instance is:

00:05.0 Ethernet controller [0200]: Amazon.com, Inc. Elastic Network
Adapter (ENA) [1d0f:ec20]
Suggested-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Guilherme G. Piccoli <gpiccoli@canonical.com>
Acked-by: Sameeh Jubran <sameehj@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The lib files should not be defined as TEST_PROGS, or we will run them
in run_kselftest.sh.

Also remove ethtool_lib.sh exec permission.

Fixes: 81573b18 ("selftests/net/forwarding: add Makefile to install tests")
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Find some tests are missed in Makefile by running:
for file in $(ls *.sh); do grep -q $file Makefile || echo $file; done
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

TCP recvmsg() calls skb_copy_datagram_iter(), which
calls an indirect function (cb pointing to simple_copy_to_iter())
for every MSS (fragment) present in the skb.

CONFIG_RETPOLINE=y forces a very expensive operation
that we can avoid thanks to indirect call wrappers.

This patch gives a 13% increase of performance on
a single flow, if the bottleneck is the thread reading
the TCP socket.

Fixes: 950fcaec ("datagram: consolidate datagram copy to iter helpers")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/chelsio/cxgb4/cxgb4_filter.c: In function cxgb4_get_free_ftid:
drivers/net/ethernet/chelsio/cxgb4/cxgb4_filter.c:547:23:
 warning: variable tab set but not used [-Wunused-but-set-variable]

commit 8d174351 ("cxgb4: rework TC filter rule insertion across regions")
involved this, remove it.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Pull zonefs fix from Damien Le Moal:
 "A single fix from me to correctly handle the size of read-only zone
  files"

* tag 'zonefs-5.6-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/zonefs:
  zonfs: Fix handling of read-only zones

The write pointer of zones in the read-only consition is defined as
invalid by the SCSI ZBC and ATA ZAC specifications. It is thus not
possible to determine the correct size of a read-only zone file on
mount. Fix this by handling read-only zones in the same manner as
offline zones by disabling all accesses to the zone (read and write)
and initializing the inode size of the read-only zone to 0).

For zones found to be in the read-only condition at runtime, only
disable write access to the zone and keep the size of the zone file to
its last updated value to allow the user to recover previously written
data.

Also fix zonefs documentation file to reflect this change.
Signed-off-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>

Pablo Neira Ayuso says:

====================
Netfilter fixes for net

The following patchset contains Netfilter fixes for net:

1) A new selftest for nf_queue, from Florian Westphal. This test
   covers two recent fixes: 07f8e4d0 ("tcp: also NULL skb->dev
   when copy was needed") and b738a185 ("tcp: ensure skb->dev is
   NULL before leaving TCP stack").

2) The fwd action breaks with ifb. For safety in next extensions,
   make sure the fwd action only runs from ingress until it is extended
   to be used from a different hook.

3) The pipapo set type now reports EEXIST in case of subrange overlaps.
   Update the rbtree set to validate range overlaps, so far this
   validation is only done only from userspace. From Stefano Brivio.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Saeed Mahameed says:

====================
Mellanox, mlx5 fixes 2020-03-24

This series introduces some fixes to mlx5 driver.

From Aya, Fixes to the RX error recovery flows
From Leon, Fix IB capability mask

Please pull and let me know if there is any problem.

For -stable v5.5
 ('net/mlx5_core: Set IB capability mask1 to fix ib_srpt connection failure')

For -stable v5.4
 ('net/mlx5e: Fix ICOSQ recovery flow with Striding RQ')
 ('net/mlx5e: Do not recover from a non-fatal syndrome')
 ('net/mlx5e: Fix missing reset of SW metadata in Striding RQ reset')
 ('net/mlx5e: Enhance ICOSQ WQE info fields')

The above patch ('net/mlx5e: Enhance ICOSQ WQE info fields')
will fail to apply cleanly on v5.4 due to a trivial contextual conflict,
but it is an important fix, do I need to do something about it or just
assume Greg will know how to handle this ?
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

The original change fixed an issue on RTL8168b by mimicking the vendor
driver behavior to disable MSI on chip versions before RTL8168d.
This however now caused an issue on a system with RTL8168c, see [0].
Therefore leave MSI disabled on RTL8168b, but re-enable it on RTL8168c.

[0] https://bugzilla.redhat.com/show_bug.cgi?id=1792839

Fixes: 003bd5b4 ("r8169: don't use MSI before RTL8168d")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

We are having multiple review cycles with all vendors trying
to implement devlink-info. Let's expand the documentation with
more information about what's implemented and motivation behind
this interface in an attempt to make the implementations easier.

Describe what each info section is supposed to contain, and make
some references to other HW interfaces (PCI caps).

Document how firmware management is expected to look, to make
it clear how devlink-info and devlink-flash work in concert.

Name some future work.

v2: - improve wording
v3: - improve wording
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

The DT binding for this PHY describes an *optional* clock property.
Due to a bug in the error handling logic, we are actually ignoring this
clock *all* of the time so far.

Fix this by using devm_clk_get_optional() to handle this clock properly.

Fixes: b78ac6ec ("net: phy: mdio-bcm-unimac: Allow configuring MDIO clock divider")
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

It looks like the VSC8584 PHY driver is rolling its own RGMII delay
configuration code, despite the fact that the logic is mostly the same.

In fact only the register layout and position for the RGMII controls has
changed. So we need to adapt and parameterize the PHY-dependent bit
fields when calling the new generic function.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Tested-by: Antoine Tenart <antoine.tenart@bootlin.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Andre Przywara says:

====================
net: axienet: Update error handling and add 64-bit DMA support

a minor update, fixing the 32-bit build breakage, and brightening up
Dave's christmas tree. Rebased against latest net-next/master.

This series is based on net-next as of today (9970de8b), which
includes Russell's fixes [1], solving the SGMII issues I have had.

[1] https://lore.kernel.org/netdev/E1j6trA-0003GY-N1@rmk-PC.armlinux.org.uk/

Changelog v2 .. v3:
- Use two "left-shifts by 16" to fix builds with 32-bit phys_addr_t
- reorder variable declarations

Changelog v1 .. v2:
- Add Reviewed-by: tags from Radhey
- Extend kerndoc documentation
- Convert DMA error handler tasklet to work queue
- log DMA mapping errors
- mark DMA mapping error checks as unlikely (in "hot" paths)
- return NETDEV_TX_OK on TX DMA mapping error (increasing TX drop counter)
- Request eth IRQ as an optional IRQ
- Remove no longer needed MDIO IRQ register names
- Drop DT propery check for address width, assume full 64 bit

This series updates the Xilinx Axienet driver to work on our board
here. One big issue was broken SGMII support, which Russell fixed already
(in net-next).
While debugging and understanding the driver, I found several problems
in the error handling and cleanup paths, which patches 2-7 address.
Patch 8 removes a annoying error message, patch 9 paves the way for newer
revisions of the IP. The next patch adds mii-tool support, just for good
measure.

The next four patches add support for 64-bit DMA. This is an integration
option on newer IP revisions (>= v7.1), and expects MSB bits in formerly
reserved registers. Without writing to those MSB registers, the state
machine won't trigger, so it's mandatory to access them, even if they
are zero. Patches 11 and 12 prepare the code by adding accessors, to
wrap this properly and keep it working on older IP revisions.
Patch 13 enables access to the MSB registers, by trying to write a
non-zero value to them and checking if that sticks. Older IP revisions
always read those registers as zero.
Patch 14 then adjusts the DMA mask, based on the autodetected MSB
feature. It uses the full 64 bits in this case, the rest of the system
(actual physical addresses in use) should provide a natural limit if the
chip has connected fewer address lines. If not, the parent DT node can
use a dma-range property.

The Xilinx PG138 and PG021 documents (in versions 7.1 in both cases)
were used for this series.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

With all DMA address accesses wrapped, we can actually support 64-bit
DMA if this option was chosen at IP integration time.
If the IP has been configured for an address width greater than 32 bits,
we assume the full 64 bit DMA width is working. In practise this will be
limited by the actual system address bus width, which will ideally be the
same as the DMA IP address width.
If this is not the case, the actual width can still be configured using a
dma-ranges property in the parent of the MAC node.

This increases the DMA mask on those systems to let the kernel choose
buffers from memory at higher addresses.
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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>

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>