Bad header can have large length field which can cause OOB.
cptr is the last bytes for read, and the eeprom is parsed
from high to low address. The OOB, triggered by the condition
length > cptr could cause memory error with a read on
negative index.

There are some sanity check around length, but it is not
compared with cptr (the remaining bytes). Here, the
corrupted/bad EEPROM can cause panic.

I was able to reproduce the crash, but I cannot find the
log and the reproducer now. After I applied the patch, the
bug is no longer reproducible.
Signed-off-by: Zekun Shen <bruceshenzk@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/YM3xKsQJ0Hw2hjrc@Zekuns-MBP-16.fios-router.home

When receiving a beacon or probe response, we should update the
boottime_ns field which is the timestamp the frame was received at.
(cf mac80211.h)

This fixes a scanning issue with Android since it relies on this
timestamp to determine when the AP has been seen for the last time
(via the nl80211 BSS_LAST_SEEN_BOOTTIME parameter).
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Reviewed-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1629992768-23785-1-git-send-email-loic.poulain@linaro.org

The WLAN NV firmware blob differs between platforms, and possibly
devices, so add support in the wcn36xx driver for reading the path of
this file from DT in order to allow these files to live in a generic
file system (or linux-firmware).

For some reason the parent (wcnss_ctrl) also needs to upload this blob,
so rather than specifying the same information in both nodes wcn36xx
reads the string from the parent's of_node.
Signed-off-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Tested-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Tested-by: Aníbal Limón <anibal.limon@linaro.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20210824171225.686683-1-bjorn.andersson@linaro.org

If the operating channel is the first in the scan list, it was seen that
a finish scan request would be sent before a start scan request was
sent, causing the firmware to fail all future scans. Track the current
channel being scanned to avoid requesting the scan finish before it
starts.

Cc: <stable@vger.kernel.org>
Fixes: 5973a294 ("wcn36xx: Fix software-driven scan")
Signed-off-by: Joseph Gates <jgates@squareup.com>
Signed-off-by: Loic Poulain <loic.poulain@linaro.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1629286303-13179-1-git-send-email-loic.poulain@linaro.org

Juhee Kang says:

====================
samples: pktgen: enhance the ability to print the execution results of samples

This patch series improves the ability to print the execution result of pktgen
samples by adding a line which calls the function before termination and adding
trap SIGINT. Also, this series documents the latest pktgen usage options.

Currently, pktgen samples print the execution result when terminated usually.
However, sample03 is not working properly.

This is results of sample04 and sample03:

    # DEV=eth0 DEST_IP=10.1.0.1 DST_MAC=00:11:22:33:44:55 ./pktgen_sample04_many_flows.sh -n 1
    Running... ctrl^C to stop
    Device: eth0@0
    Result: OK: 19(c5+d13) usec, 1 (60byte,0frags)
    51762pps 24Mb/sec (24845760bps) errors: 0

    # DEV=eth0 DEST_IP=10.1.0.1 DST_MAC=00:11:22:33:44:55 ./pktgen_sample03_burst_single_flow.sh -n 1
    Running... ctrl^C to stop

Because sample03 doesn't call the function which prints the execution result
when terminated normally, unlike other samples. So the first commit solves
this issue by adding a line which calls the function before termination.

Also, all pktgen samples are able to send infinite messages per thread by
setting the count option to 0, and pktgen is stopped by Ctrl-C. However,
the sample besides sample{3...5} don't work appropriately because Ctrl-C stops
the script, not just pktgen.

This is results of samples:

    # DEV=eth0 DEST_IP=10.1.0.1 DST_MAC=00:11:22:33:44:55 ./pktgen_sample04_many_flows.sh -n 0
    Running... ctrl^C to stop
    ^CDevice: eth0@0
    Result: OK: 569657(c569538+d118) usec, 84650 (60byte,0frags)
    148597pps 71Mb/sec (71326560bps) errors: 0

    # DEV=eth0 DEST_IP=10.1.0.1 DST_MAC=00:11:22:33:44:55 ./pktgen_sample01_simple.sh -n 0
    Running... ctrl^C to stop
    ^C

    # DEV=eth0 DEST_IP=10.1.0.1 DST_MAC=00:11:22:33:44:55 ./pktgen_sample02_multiqueue.sh -n 0
    Running... ctrl^C to stop
    ^C

    # DEV=eth0 DEST_IP=10.1.0.1 DST_MAC=00:11:22:33:44:55 ./pktgen_sample06_numa_awared_queue_irq_affinity.sh -n 0
    Running... ctrl^C to stop
    ^C

    # DEV=eth0 DEST_IP=10.1.0.1 DST_MAC=00:11:22:33:44:55 ./pktgen_bench_xmit_mode_netif_receive.sh -n 0
    Running... ctrl^C to stop
    ^C

    # DEV=eth0 DEST_IP=10.1.0.1 DST_MAC=00:11:22:33:44:55 ./pktgen_bench_xmit_mode_queue_xmit.sh -n 0
    Running... ctrl^C to stop
    ^C

So the second commit solves this issue by adding trap SIGINT. Also, changes
control_c function to print_results to maintain consistency with other samples
on the first commit and second commit.

And current pktgen.rst documentation doesn't add the latest pktgen sample
usage options such as count and IPv6, and so on. Also, the old pktgen
sample scripts are still included in the document. The old scripts were removed
by the commit a4b6ade8 ("samples/pktgen: remove remaining old pktgen
sample scripts").

Thus, the last commit documents the latest pktgen sample usage and removes
old sample scripts. And fixes a minor typo.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Currently, the pktgen.rst documentation doesn't cover the latest pktgen
sample usage options such as count and IPv6, and so on. Also, this
documentation includes the old sample scripts which are no longer use
because it was removed by the commit a4b6ade8 ("samples/pktgen :
remove remaining old pktgen sample scripts")

Thus, this commit documents pktgen sample usage using the latest options
and removes old sample scripts, and fixes a minor typo.
Signed-off-by: Juhee Kang <claudiajkang@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

All pktgen samples can send indefinitely num messages per thread by
setting the count option to 0(-n 0). If running sample with setting
count 0 and press Ctrl-C to stop this program, the program prints the
result of the execution so far. Currently, the samples besides
sample{3...5} don't work properly. Because Ctrl-C stops the script, not
just pktgen.

This is results of samples:

    # DEV=eth0 DEST_IP=10.1.0.1 DST_MAC=00:11:22:33:44:55 ./pktgen_sample04_many_flows.sh -n 0
    Running... ctrl^C to stop
    ^CDevice: eth0@0
    Result: OK: 569657(c569538+d118) usec, 84650 (60byte,0frags)
    148597pps 71Mb/sec (71326560bps) errors: 0

    # DEV=eth0 DEST_IP=10.1.0.1 DST_MAC=00:11:22:33:44:55 ./pktgen_sample01_simple.sh -n 0
    Running... ctrl^C to stop
    ^C

In order to solve this, this commit adds trap SIGINT. Also, this commit
changes control_c function to print_result to maintain consistency with
other samples.
Signed-off-by: Juhee Kang <claudiajkang@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Currently, most pktgen samples print the execution result when the
program is terminated normally. However, sample03 doesn't work
appropriately.

This is results of samples:

    # DEV=eth0 DEST_IP=10.1.0.1 DST_MAC=00:11:22:33:44:55 ./pktgen_sample04_many_flows.sh -n 1
    Running... ctrl^C to stop
    Device: eth0@0
    Result: OK: 19(c5+d13) usec, 1 (60byte,0frags)
    51762pps 24Mb/sec (24845760bps) errors: 0

    # DEV=eth0 DEST_IP=10.1.0.1 DST_MAC=00:11:22:33:44:55 ./pktgen_sample03_burst_single_flow.sh -n 1
    Running... ctrl^C to stop

The reason why it doesn't print the execution result when the program is
terminated usually is that sample03 doesn't call the function which
prints the result, unlike other samples.

So, this commit solves this issue by calling the function before
termination. Also, this commit changes control_c function to
print_result to maintain consistency with other samples.
Signed-off-by: Juhee Kang <claudiajkang@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Sunil Goutham says:

====================
Octeontx2: Traffic shaping and SDP link config support

This patch series adds support for traffic shaping configuration
on all silicons available after 96xx C0. And also adds SDP link
related configuration needed when Octeon is connected as an end-point
and traffic needs to flow from end-point to host and vice versa.

Series also has other changes like
- New mbox messages in admin function driver for PF/VF drivers
  to retrieve available HW resource count. HW resources like block LFs,
  bandwidth profiles etc are covered.
- Added PTP device ID for new CN10K and 95O silicons.
- etc
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Added mbox for PF/VF drivers to retrieve current ingress bandwidth
profile free count. Also added current policer timeunit
configuration info based on which ratelimiting decisions can be
taken by PF/VF drivers.
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

New usecases are popping up where in user wants to install common MCAM
filters for all interfaces. Having channel verification will result in
duplicating such MCAM filters for each of the ingress interface. Hence
removed channel verification.
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

CN10K slicon has different device id for PTP device.
Hence this patch updates the driver with new id.
Though ptp driver being a separate driver AF manages
configuring PTP block by all PFs. To manage ptp, AF
driver checks in its probe whether
1. ptp hardware device found on silicon
2. A driver is bound to ptp device
3. The ptp driver probe is successful

In failure of cases 1 and 3, AF proceeds with out ptp
and for case 2 defers the probe. This patch refactors
code also to check for all the PTP device ids given in
ptp device ids table for case 1.

Also added PTP device ID for 95O silicon
Signed-off-by: Subbaraya Sundeep <sbhatta@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Upon receiving the MBOX_MSG_FREE_RSRC_CNT, the AF will find out the
current number of free resources and reply it back to the requester. No
guarantee is given on the future state of the free resources yet.
If another requester sends MBOX_MSG_ATTACH_RESOURCES after this call,
the number of available resources might change.
Signed-off-by: George Cherian <george.cherian@marvell.com>
Signed-off-by: Stanislaw Kardach <skardach@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Added support for packet IO via SDK links which is used when
Octeon is connected as a end-point. Traffic host to end-point
and vice versa flow through SDP links. This patch also support
dual SDP blocks supported in 98xx silicon.
Signed-off-by: Radha Mohan Chintakuntla <radhac@marvell.com>
Signed-off-by: Nalla Pradeep <pnalla@marvell.com>
Signed-off-by: Subrahmanyam Nilla <snilla@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

In 98xx, there are 2 NIX blocks and 4 LBK blocks present. The way
these NIX-LBK should be configured depends on the use case. By
default loopback functionality is supported in AF VF pairs which
are attached to NIX0 and NIX1 LFs alternatively to ensure load
balancing. NIX0 transmits a packet to LBK1 which will be received
by NIX1 and packet transmitted by NIX1 will get received by NIX0 via
LBK2.

There are some requirements where only one AF VF is used and respective
NIX is expected to operate in a mode where it can receive it own packet
back. This can be achieved if NIX0 sends packet to LBK0 and not LBK1.
Adding a flag in LF alloc request mailbox which can setup NIX0 to use
LBK0 and NIX1 can use LBK3.
Signed-off-by: Harman Kalra <hkalra@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Unlike OcteonTx2, the channel numbers used by CGX/RPM
and LBK on CN10K silicons aren't fixed in HW. They are
SW programmable, hence we cannot derive transmit link
from static channel numbers anymore. Get the same from
admin function via mailbox.
Signed-off-by: Subbaraya Sundeep <sbhatta@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Before C0 HW revision, The RSS adder was computed based the
following static formula.

rss_adder<7:0> = flow_tag<7:0> ^ flow_tag<15:8> ^
flow_tag<23:16> ^ flow_tag<31:24>

The above scheme has the following drawbacks:
1) It is not in line with other standard NIC behavior.
2) There can be an SW use case where SW can compute the hash
upfront using Toeplitz function and predict the queue selection
to optimize some packet lookup function. The nonstandard
way of doing XOR makes the consumer to not predict the queue selection.

C0 HW revision onwards, The HW can configure the
rss_adder<7:0> as flow_tag<7:0> to align with standard NICs.

This patch adds an option to select legacy RSS adder mode
vs standard NIC behavior by setting NIX_LF_RSS_TAG_LSB_AS_ADDER flag.

Since this bit field is used as reserved in old HW revisions,
No need to have an additional HW version check.
Signed-off-by: Jerin Jacob <jerinj@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Starting from 96xx C0 onwards all silicons support traffic shaping.
This patch enables that feature along with other changes
- When PIR/CIR shaping config is modified, toggle SW_XOFF
  for config to take effect
- Before SMQ flush, clear SW_XOFF at all parent schedulers
- Support to read current transmit scheduler configuration via mbox
Signed-off-by: Nithin Dabilpuram <ndabilpuram@marvell.com>
Signed-off-by: Geetha sowjanya <gakula@marvell.com>
Signed-off-by: Subbaraya Sundeep <sbhatta@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

it's helpful for complie test in other platform(e.g.X86)
Signed-off-by: Cai Huoqing <caihuoqing@baidu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

NIX_AF_TX_LINKX_NORM_CREDIT holds running counter of
tx credits available per link. But, tx credits should be
configured based on MTU config. So MTU change needs tx
credit count update.

An issue exists whereby when both PF & VF are enabled and
PF traffic is flowing, if VF requests for MTU update,
updating the NORM_CREDIT register will lead to corruption
of credit count and subsequent deadlock of tx link as
the NORM_CREDIT register holds running count.

This patch provides workaround by pausing link traffic
using NIX_AF_TL1X_SW_XOFF, waiting for existing packets to
drain, and used credits be returned before updating new
credit count.
Signed-off-by: Nithin Dabilpuram <ndabilpuram@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: Geetha sowjanya <gakula@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Clear and disable interrupt before queueing work as there might be
a chance that work gets completed on other core faster and
interrupt enable as a part of the work completes before
interrupt disable in the interrupt context. This leads to
permanent disable of interrupt.
Signed-off-by: Nithin Dabilpuram <ndabilpuram@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: Geetha sowjanya <gakula@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Set NPA batch allocation engine to process 35 cache lines
per turn on CN10k platform.
Signed-off-by: Geetha sowjanya <gakula@marvell.com>
Signed-off-by: Sunil Goutham <sgoutham@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Function 'mctp_dev_get_rtnl' is declared twice, so remove the
repeated declaration.

Cc: Jeremy Kerr <jk@codeconstruct.com.au>
Cc: Matt Johnston <matt@codeconstruct.com.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Merge tag 'linux-can-next-for-5.15-20210825' of git://git.kernel.org/pub/scm/linux/kernel/git/mkl/linux-can-next

Marc Kleine says:

====================
pull-request: can-next 2021-08-25

this is a pull request of 4 patches for net-next/master.

The first patch is by Cai Huoqing, and enables COMPILE_TEST for the
rcar CAN drivers.

Lad Prabhakar contributes a patch for the rcar_canfd driver, fixing a
redundant assignment.

The last 2 patches are by Tang Bin, target the mscan driver, and clean
up the driver by converting it to of_device_get_match_data() and
removing a useless BUG_ON.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Biju Das says:

====================
Add Factorisation code to support Gigabit Ethernet driver

The DMAC and EMAC blocks of Gigabit Ethernet IP found on RZ/G2L SoC are
similar to the R-Car Ethernet AVB IP.

The Gigabit Ethernet IP consists of Ethernet controller (E-MAC), Internal
TCP/IP Offload Engine (TOE)  and Dedicated Direct memory access controller
(DMAC).

With a few changes in the driver we can support both IPs.

This patch series aims to add factorisation code to support RZ/G2L SoC,
hardware feature bits for gPTP feature, Multiple irq feature and
optional reset support.

Ref:-
 * https://lore.kernel.org/linux-renesas-soc/TYCPR01MB59334319695607A2683C1A5E86E59@TYCPR01MB5933.jpnprd01.prod.outlook.com/T/#t
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

Reset support is present on R-Car. Let's support it, if it is
available.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The E-MAC IP on the R-Car AVB module has different initialization
parameters for RX frame size, duplex settings, different offset
for transfer speed setting and has magic packet detection support
compared to E-MAC on RZ/G2L Gigabit Ethernet module. Factorise
the ravb_emac_init function to support the later SoC.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The DMAC IP on the R-Car AVB module has different initialization
parameters for RCR, TGC, TCCR, RIC0, RIC2, and TIC compared to
DMAC IP on the RZ/G2L Gigabit Ethernet module. Factorise the
ravb_dmac_init function to support the later SoC.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

RZ/G2L supports HW checksum on RX and TX whereas R-Car supports on RX.
Factorise ravb_set_features to support this feature.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

R-Car supports 100 and 1000 Mbps transfer speed whereas RZ/G2L
in addition support 10Mbps. Factorise ravb_adjust_link function
in order to support 10Mbps speed.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

R-Car uses an extended descriptor in RX whereas, RZ/G2L uses
normal descriptor in RX. Factorise the ravb_rx function to
support the later SoC.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The ravb_ring_init function uses an extended descriptor in RX for
R-Car and normal descriptor for RZ/G2L. Add a helper function
for RX ring buffer allocation to support later SoC.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

The ravb_ring_format function uses an extended descriptor in RX
for R-Car compared to the normal descriptor for RZ/G2L. Factorise
RX ring buffer buildup to extend the support for later SoC.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

R-Car uses extended descriptor in RX, whereas RZ/G2L uses normal
descriptor. Factorise ravb_ring_free function so that it can
support later SoC.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

There are some H/W differences for the gPTP feature between
R-Car Gen3, R-Car Gen2, and RZ/G2L as below.

1) On R-Car Gen3, gPTP support is active in config mode.
2) On R-Car Gen2, gPTP support is not active in config mode.
3) RZ/G2L does not support the gPTP feature.

Add a ptp_cfg_active hw feature bit to struct ravb_hw_info for
supporting gPTP active in config mode for R-Car Gen3.
This patch also removes enum ravb_chip_id, chip_id from both
struct ravb_hw_info and struct ravb_private, as it is unused.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

There are some H/W differences for the gPTP feature between
R-Car Gen3, R-Car Gen2, and RZ/G2L as below.

1) On R-Car Gen2, gPTP support is not active in config mode.
2) On R-Car Gen3, gPTP support is active in config mode.
3) RZ/G2L does not support the gPTP feature.

Add a no_ptp_cfg_active hw feature bit to struct ravb_hw_info for
handling gPTP for R-Car Gen2.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

R-Car Gen3 supports separate interrupts for E-MAC and DMA queues,
whereas R-Car Gen2 and RZ/G2L have a single interrupt instead.

Add a multi_irq hw feature bit to struct ravb_hw_info to enable
this only for R-Car Gen3.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

For addressing 4 bytes alignment restriction on transmission
buffer for R-Car Gen2 we use 2 descriptors whereas it is a single
descriptor for other cases.
Replace the macros NUM_TX_DESC_GEN[23] with magic number and
add a comment to explain it.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Suggested-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Vladimir Oltean says:

====================
Make sja1105 treat tag_8021q VLANs more like real DSA tags

This series solves a nuisance with the sja1105 driver, which is that
non-DSA tagged packets sent directly by the DSA master would still exit
the switch just fine.

We also had an issue for packets coming from the outside world with a
crafted DSA tag, the switch would not reject that tag but think it was
valid.
====================

Introduced in commit 38b5beea ("net: dsa: sja1105: prepare tagger
for handling DSA tags and VLAN simultaneously"), the sja1105_xmit_tpid
function solved quite a different problem than our needs are now.

Then, we used best-effort VLAN filtering and we were using the xmit_tpid
to tunnel packets coming from an 8021q upper through the TX VLAN allocated
by tag_8021q to that egress port. The need for a different VLAN protocol
depending on switch revision came from the fact that this in itself was
more of a hack to trick the hardware into accepting tunneled VLANs in
the first place.

Right now, we deny 8021q uppers (see sja1105_prechangeupper). Even if we
supported them again, we would not do that using the same method of
{tunneling the VLAN on egress, retagging the VLAN on ingress} that we
had in the best-effort VLAN filtering mode. It seems rather simpler that
we just allocate a VLAN in the VLAN table that is simply not used by the
bridge at all, or by any other port.

Anyway, I have 2 gripes with the current sja1105_xmit_tpid:

1. When sending packets on behalf of a VLAN-aware bridge (with the new
   TX forwarding offload framework) plus untagged (with the tag_8021q
   VLAN added by the tagger) packets, we can see that on SJA1105P/Q/R/S
   and later (which have a qinq_tpid of ETH_P_8021AD), some packets sent
   through the DSA master have a VLAN protocol of 0x8100 and others of
   0x88a8. This is strange and there is no reason for it now. If we have
   a bridge and are therefore forced to send using that bridge's TPID,
   we can as well blend with that bridge's VLAN protocol for all packets.

2. The sja1105_xmit_tpid introduces a dependency on the sja1105 driver,
   because it looks inside dp->priv. It is desirable to keep as much
   separation between taggers and switch drivers as possible. Now it
   doesn't do that anymore.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>