linux-stable.git/drivers/net/dsa, branch v5.6.4 Linux kernel stable tree net: dsa: mt7530: fix null pointer dereferencing in port5 setup 2020-04-13T11:17:50+00:00 Chuanhong Guo gch981213@gmail.com 2020-04-03T11:28:24+00:00 65fca16cbf0257d9e3609aca30956000605992e1 [ Upstream commit 0452800f6db4ed0a42ffb15867c0acfd68829f6a ] The 2nd gmac of mediatek soc ethernet may not be connected to a PHY and a phy-handle isn't always available. Unfortunately, mt7530 dsa driver assumes that the 2nd gmac is always connected to switch port 5 and setup mt7530 according to phy address of 2nd gmac node, causing null pointer dereferencing when phy-handle isn't defined in dts. This commit fix this setup code by checking return value of of_parse_phandle before using it. Fixes: 38f790a80560 ("net: dsa: mt7530: Add support for port 5") Signed-off-by: Chuanhong Guo <gch981213@gmail.com> Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Tested-by: René van Dorst <opensource@vdorst.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 0452800f6db4ed0a42ffb15867c0acfd68829f6a ]

The 2nd gmac of mediatek soc ethernet may not be connected to a PHY
and a phy-handle isn't always available.
Unfortunately, mt7530 dsa driver assumes that the 2nd gmac is always
connected to switch port 5 and setup mt7530 according to phy address
of 2nd gmac node, causing null pointer dereferencing when phy-handle
isn't defined in dts.
This commit fix this setup code by checking return value of
of_parse_phandle before using it.

Fixes: 38f790a80560 ("net: dsa: mt7530: Add support for port 5")
Signed-off-by: Chuanhong Guo <gch981213@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: René van Dorst <opensource@vdorst.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net: dsa: bcm_sf2: Ensure correct sub-node is parsed 2020-04-13T11:17:50+00:00 Florian Fainelli f.fainelli@gmail.com 2020-04-05T20:00:30+00:00 c2a784e058ffd911747805faa84ae639110789fb [ Upstream commit afa3b592953bfaecfb4f2f335ec5f935cff56804 ] When the bcm_sf2 was converted into a proper platform device driver and used the new dsa_register_switch() interface, we would still be parsing the legacy DSA node that contained all the port information since the platform firmware has intentionally maintained backward and forward compatibility to client programs. Ensure that we do parse the correct node, which is "ports" per the revised DSA binding. Fixes: d9338023fb8e ("net: dsa: bcm_sf2: Make it a real platform device driver") Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit afa3b592953bfaecfb4f2f335ec5f935cff56804 ]

When the bcm_sf2 was converted into a proper platform device driver and
used the new dsa_register_switch() interface, we would still be parsing
the legacy DSA node that contained all the port information since the
platform firmware has intentionally maintained backward and forward
compatibility to client programs. Ensure that we do parse the correct
node, which is "ports" per the revised DSA binding.

Fixes: d9338023fb8e ("net: dsa: bcm_sf2: Make it a real platform device driver")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net: dsa: bcm_sf2: Do not register slave MDIO bus with OF 2020-04-13T11:17:49+00:00 Florian Fainelli f.fainelli@gmail.com 2020-04-04T21:35:17+00:00 9150efb181170a47951585f3ff61ccda114179d9 [ Upstream commit 536fab5bf5826404534a6c271f622ad2930d9119 ] We were registering our slave MDIO bus with OF and doing so with assigning the newly created slave_mii_bus of_node to the master MDIO bus controller node. This is a bad thing to do for a number of reasons: - we are completely lying about the slave MII bus is arranged and yet we still want to control which MDIO devices it probes. It was attempted before to play tricks with the bus_mask to perform that: https://www.spinics.net/lists/netdev/msg429420.html but the approach was rightfully rejected - the device_node reference counting is messed up and we are effectively doing a double probe on the devices we already probed using the master, this messes up all resources reference counts (such as clocks) The proper fix for this as indicated by David in his reply to the thread above is to use a platform data style registration so as to control exactly which devices we probe: https://www.spinics.net/lists/netdev/msg430083.html By using mdiobus_register(), our slave_mii_bus->phy_mask value is used as intended, and all the PHY addresses that must be redirected towards our slave MDIO bus is happening while other addresses get redirected towards the master MDIO bus. Fixes: 461cd1b03e32 ("net: dsa: bcm_sf2: Register our slave MDIO bus") Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit 536fab5bf5826404534a6c271f622ad2930d9119 ]

We were registering our slave MDIO bus with OF and doing so with
assigning the newly created slave_mii_bus of_node to the master MDIO bus
controller node. This is a bad thing to do for a number of reasons:

- we are completely lying about the slave MII bus is arranged and yet we
  still want to control which MDIO devices it probes. It was attempted
  before to play tricks with the bus_mask to perform that:
  https://www.spinics.net/lists/netdev/msg429420.html but the approach
  was rightfully rejected

- the device_node reference counting is messed up and we are effectively
  doing a double probe on the devices we already probed using the
  master, this messes up all resources reference counts (such as clocks)

The proper fix for this as indicated by David in his reply to the
thread above is to use a platform data style registration so as to
control exactly which devices we probe:
https://www.spinics.net/lists/netdev/msg430083.html

By using mdiobus_register(), our slave_mii_bus->phy_mask value is used
as intended, and all the PHY addresses that must be redirected towards
our slave MDIO bus is happening while other addresses get redirected
towards the master MDIO bus.

Fixes: 461cd1b03e32 ("net: dsa: bcm_sf2: Register our slave MDIO bus")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net: dsa: ksz: Select KSZ protocol tag 2020-04-08T07:11:02+00:00 Codrin Ciubotariu codrin.ciubotariu@microchip.com 2020-03-31T09:36:51+00:00 1c66f3b28146f60a6a1e87f119e361c9d3e429de [ Upstream commit f772148eb757b0823fbfdc2fe592d5e06c7f19b0 ] KSZ protocol tag is needed by the KSZ DSA drivers. Fixes: 0b9f9dfbfab4 ("dsa: Allow tag drivers to be built as modules") Tested-by: Cristian Birsan <cristian.birsan@microchip.com> Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
[ Upstream commit f772148eb757b0823fbfdc2fe592d5e06c7f19b0 ]

KSZ protocol tag is needed by the KSZ DSA drivers.

Fixes: 0b9f9dfbfab4 ("dsa: Allow tag drivers to be built as modules")
Tested-by: Cristian Birsan <cristian.birsan@microchip.com>
Signed-off-by: Codrin Ciubotariu <codrin.ciubotariu@microchip.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net: dsa: mt7530: Change the LINK bit to reflect the link status 2020-03-20T04:10:49+00:00 René van Dorst opensource@vdorst.com 2020-03-19T13:47:56+00:00 22259471b51925353bd7b16f864c79fdd76e425e Andrew reported: After a number of network port link up/down changes, sometimes the switch port gets stuck in a state where it thinks it is still transmitting packets but the cpu port is not actually transmitting anymore. In this state you will see a message on the console "mtk_soc_eth 1e100000.ethernet eth0: transmit timed out" and the Tx counter in ifconfig will be incrementing on virtual port, but not incrementing on cpu port. The issue is that MAC TX/RX status has no impact on the link status or queue manager of the switch. So the queue manager just queues up packets of a disabled port and sends out pause frames when the queue is full. Change the LINK bit to reflect the link status. Fixes: b8f126a8d543 ("net-next: dsa: add dsa support for Mediatek MT7530 switch") Reported-by: Andrew Smith <andrew.smith@digi.com> Signed-off-by: René van Dorst <opensource@vdorst.com> Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Andrew reported:

After a number of network port link up/down changes, sometimes the switch
port gets stuck in a state where it thinks it is still transmitting packets
but the cpu port is not actually transmitting anymore. In this state you
will see a message on the console
"mtk_soc_eth 1e100000.ethernet eth0: transmit timed out" and the Tx counter
in ifconfig will be incrementing on virtual port, but not incrementing on
cpu port.

The issue is that MAC TX/RX status has no impact on the link status or
queue manager of the switch. So the queue manager just queues up packets
of a disabled port and sends out pause frames when the queue is full.

Change the LINK bit to reflect the link status.

Fixes: b8f126a8d543 ("net-next: dsa: add dsa support for Mediatek MT7530 switch")
Reported-by: Andrew Smith <andrew.smith@digi.com>
Signed-off-by: René van Dorst <opensource@vdorst.com>
Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: dsa: mv88e6xxx: Add missing mask of ATU occupancy register 2020-03-12T07:01:29+00:00 Andrew Lunn andrew@lunn.ch 2020-03-11T20:02:31+00:00 012fc74517b25177dfede2ed45cd108258564e4a Only the bottom 12 bits contain the ATU bin occupancy statistics. The upper bits need masking off. Fixes: e0c69ca7dfbb ("net: dsa: mv88e6xxx: Add ATU occupancy via devlink resources") Signed-off-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net> 
Only the bottom 12 bits contain the ATU bin occupancy statistics. The
upper bits need masking off.

Fixes: e0c69ca7dfbb ("net: dsa: mv88e6xxx: Add ATU occupancy via devlink resources")
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: dsa: sja1105: Don't destroy not-yet-created xmit_worker 2020-03-01T05:58:46+00:00 Vladimir Oltean olteanv@gmail.com 2020-02-29T20:30:07+00:00 52c0d4e306ca0261a896f5e2ad823112195b7f4b Fixes the following NULL pointer dereference on PHY connect error path teardown: [ 2.291010] sja1105 spi0.1: Probed switch chip: SJA1105T [ 2.310044] sja1105 spi0.1: Enabled switch tagging [ 2.314970] fsl-gianfar soc:ethernet@2d90000 eth2: error -19 setting up slave phy [ 2.322463] 8<--- cut here --- [ 2.325497] Unable to handle kernel NULL pointer dereference at virtual address 00000018 [ 2.333555] pgd = (ptrval) [ 2.336241] [00000018] *pgd=00000000 [ 2.339797] Internal error: Oops: 5 [#1] SMP ARM [ 2.344384] Modules linked in: [ 2.347420] CPU: 1 PID: 64 Comm: kworker/1:1 Not tainted 5.5.0-rc5 #1 [ 2.353820] Hardware name: Freescale LS1021A [ 2.358070] Workqueue: events deferred_probe_work_func [ 2.363182] PC is at kthread_destroy_worker+0x4/0x74 [ 2.368117] LR is at sja1105_teardown+0x70/0xb4 [ 2.372617] pc : [<c036cdd4>] lr : [<c0b89238>] psr: 60000013 [ 2.378845] sp : eeac3d30 ip : eeab1900 fp : eef45480 [ 2.384036] r10: eef4549c r9 : 00000001 r8 : 00000000 [ 2.389227] r7 : eef527c0 r6 : 00000034 r5 : ed8ddd0c r4 : ed8ddc40 [ 2.395714] r3 : 00000000 r2 : 00000000 r1 : eef4549c r0 : 00000000 [ 2.402204] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none [ 2.409297] Control: 10c5387d Table: 8020406a DAC: 00000051 [ 2.415008] Process kworker/1:1 (pid: 64, stack limit = 0x(ptrval)) [ 2.421237] Stack: (0xeeac3d30 to 0xeeac4000) [ 2.612635] [<c036cdd4>] (kthread_destroy_worker) from [<c0b89238>] (sja1105_teardown+0x70/0xb4) [ 2.621379] [<c0b89238>] (sja1105_teardown) from [<c10717fc>] (dsa_switch_teardown.part.1+0x48/0x74) [ 2.630467] [<c10717fc>] (dsa_switch_teardown.part.1) from [<c1072438>] (dsa_register_switch+0x8b0/0xbf4) [ 2.639984] [<c1072438>] (dsa_register_switch) from [<c0b89c30>] (sja1105_probe+0x2ac/0x464) [ 2.648378] [<c0b89c30>] (sja1105_probe) from [<c0b11a5c>] (spi_drv_probe+0x7c/0xa0) [ 2.656081] [<c0b11a5c>] (spi_drv_probe) from [<c0a26ab8>] (really_probe+0x208/0x480) [ 2.663871] [<c0a26ab8>] (really_probe) from [<c0a26f0c>] (driver_probe_device+0x78/0x1c4) [ 2.672093] [<c0a26f0c>] (driver_probe_device) from [<c0a24c48>] (bus_for_each_drv+0x80/0xc4) [ 2.680574] [<c0a24c48>] (bus_for_each_drv) from [<c0a26810>] (__device_attach+0xd0/0x168) [ 2.688794] [<c0a26810>] (__device_attach) from [<c0a259d8>] (bus_probe_device+0x84/0x8c) [ 2.696927] [<c0a259d8>] (bus_probe_device) from [<c0a25f24>] (deferred_probe_work_func+0x84/0xc4) [ 2.705842] [<c0a25f24>] (deferred_probe_work_func) from [<c03667b0>] (process_one_work+0x22c/0x560) [ 2.714926] [<c03667b0>] (process_one_work) from [<c0366d8c>] (worker_thread+0x2a8/0x5d4) [ 2.723059] [<c0366d8c>] (worker_thread) from [<c036cf94>] (kthread+0x150/0x154) [ 2.730416] [<c036cf94>] (kthread) from [<c03010e8>] (ret_from_fork+0x14/0x2c) Checking for NULL pointer is correct because the per-port xmit kernel threads are created in sja1105_probe immediately after calling dsa_register_switch. Fixes: a68578c20a96 ("net: dsa: Make deferred_xmit private to sja1105") Signed-off-by: Vladimir Oltean <olteanv@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Fixes the following NULL pointer dereference on PHY connect error path
teardown:

[    2.291010] sja1105 spi0.1: Probed switch chip: SJA1105T
[    2.310044] sja1105 spi0.1: Enabled switch tagging
[    2.314970] fsl-gianfar soc:ethernet@2d90000 eth2: error -19 setting up slave phy
[    2.322463] 8<--- cut here ---
[    2.325497] Unable to handle kernel NULL pointer dereference at virtual address 00000018
[    2.333555] pgd = (ptrval)
[    2.336241] [00000018] *pgd=00000000
[    2.339797] Internal error: Oops: 5 [#1] SMP ARM
[    2.344384] Modules linked in:
[    2.347420] CPU: 1 PID: 64 Comm: kworker/1:1 Not tainted 5.5.0-rc5 #1
[    2.353820] Hardware name: Freescale LS1021A
[    2.358070] Workqueue: events deferred_probe_work_func
[    2.363182] PC is at kthread_destroy_worker+0x4/0x74
[    2.368117] LR is at sja1105_teardown+0x70/0xb4
[    2.372617] pc : [<c036cdd4>]    lr : [<c0b89238>]    psr: 60000013
[    2.378845] sp : eeac3d30  ip : eeab1900  fp : eef45480
[    2.384036] r10: eef4549c  r9 : 00000001  r8 : 00000000
[    2.389227] r7 : eef527c0  r6 : 00000034  r5 : ed8ddd0c  r4 : ed8ddc40
[    2.395714] r3 : 00000000  r2 : 00000000  r1 : eef4549c  r0 : 00000000
[    2.402204] Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
[    2.409297] Control: 10c5387d  Table: 8020406a  DAC: 00000051
[    2.415008] Process kworker/1:1 (pid: 64, stack limit = 0x(ptrval))
[    2.421237] Stack: (0xeeac3d30 to 0xeeac4000)
[    2.612635] [<c036cdd4>] (kthread_destroy_worker) from [<c0b89238>] (sja1105_teardown+0x70/0xb4)
[    2.621379] [<c0b89238>] (sja1105_teardown) from [<c10717fc>] (dsa_switch_teardown.part.1+0x48/0x74)
[    2.630467] [<c10717fc>] (dsa_switch_teardown.part.1) from [<c1072438>] (dsa_register_switch+0x8b0/0xbf4)
[    2.639984] [<c1072438>] (dsa_register_switch) from [<c0b89c30>] (sja1105_probe+0x2ac/0x464)
[    2.648378] [<c0b89c30>] (sja1105_probe) from [<c0b11a5c>] (spi_drv_probe+0x7c/0xa0)
[    2.656081] [<c0b11a5c>] (spi_drv_probe) from [<c0a26ab8>] (really_probe+0x208/0x480)
[    2.663871] [<c0a26ab8>] (really_probe) from [<c0a26f0c>] (driver_probe_device+0x78/0x1c4)
[    2.672093] [<c0a26f0c>] (driver_probe_device) from [<c0a24c48>] (bus_for_each_drv+0x80/0xc4)
[    2.680574] [<c0a24c48>] (bus_for_each_drv) from [<c0a26810>] (__device_attach+0xd0/0x168)
[    2.688794] [<c0a26810>] (__device_attach) from [<c0a259d8>] (bus_probe_device+0x84/0x8c)
[    2.696927] [<c0a259d8>] (bus_probe_device) from [<c0a25f24>] (deferred_probe_work_func+0x84/0xc4)
[    2.705842] [<c0a25f24>] (deferred_probe_work_func) from [<c03667b0>] (process_one_work+0x22c/0x560)
[    2.714926] [<c03667b0>] (process_one_work) from [<c0366d8c>] (worker_thread+0x2a8/0x5d4)
[    2.723059] [<c0366d8c>] (worker_thread) from [<c036cf94>] (kthread+0x150/0x154)
[    2.730416] [<c036cf94>] (kthread) from [<c03010e8>] (ret_from_fork+0x14/0x2c)

Checking for NULL pointer is correct because the per-port xmit kernel
threads are created in sja1105_probe immediately after calling
dsa_register_switch.

Fixes: a68578c20a96 ("net: dsa: Make deferred_xmit private to sja1105")
Signed-off-by: Vladimir Oltean <olteanv@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: dsa: mv88e6xxx: fix lockup on warm boot 2020-03-01T05:46:08+00:00 Russell King rmk+kernel@armlinux.org.uk 2020-02-28T19:39:41+00:00 0395823b8d9a4d87bd1bf74359123461c2ae801b If the switch is not hardware reset on a warm boot, interrupts can be left enabled, and possibly pending. This will cause us to enter an infinite loop trying to service an interrupt we are unable to handle, thereby preventing the kernel from booting. Ensure that the global 2 interrupt sources are disabled before we claim the parent interrupt. Observed on the ZII development revision B and C platforms with reworked serdes support, and using reboot -f to reboot the platform. Fixes: dc30c35be720 ("net: dsa: mv88e6xxx: Implement interrupt support.") Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net> 
If the switch is not hardware reset on a warm boot, interrupts can be
left enabled, and possibly pending. This will cause us to enter an
infinite loop trying to service an interrupt we are unable to handle,
thereby preventing the kernel from booting.

Ensure that the global 2 interrupt sources are disabled before we claim
the parent interrupt.

Observed on the ZII development revision B and C platforms with
reworked serdes support, and using reboot -f to reboot the platform.

Fixes: dc30c35be720 ("net: dsa: mv88e6xxx: Implement interrupt support.")
Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: dsa: mv88e6xxx: Fix masking of egress port 2020-02-27T20:29:09+00:00 Andrew Lunn andrew@lunn.ch 2020-02-27T20:20:49+00:00 3ee339eb28959629db33aaa2b8cde4c63c6289eb Add missing ~ to the usage of the mask. Reported-by: Kevin Benson <Kevin.Benson@zii.aero> Reported-by: Chris Healy <Chris.Healy@zii.aero> Fixes: 5c74c54ce6ff ("net: dsa: mv88e6xxx: Split monitor port configuration") Signed-off-by: Andrew Lunn <andrew@lunn.ch> Signed-off-by: David S. Miller <davem@davemloft.net> 
Add missing ~ to the usage of the mask.

Reported-by: Kevin Benson <Kevin.Benson@zii.aero>
Reported-by: Chris Healy <Chris.Healy@zii.aero>
Fixes: 5c74c54ce6ff ("net: dsa: mv88e6xxx: Split monitor port configuration")
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
net: dsa: bcm_sf2: Forcibly configure IMP port for 1Gb/sec 2020-02-27T00:38:23+00:00 Florian Fainelli f.fainelli@gmail.com 2020-02-24T23:56:32+00:00 98c5f7d44fef309e692c24c6d71131ee0f0871fb We are still experiencing some packet loss with the existing advanced congestion buffering (ACB) settings with the IMP port configured for 2Gb/sec, so revert to conservative link speeds that do not produce packet loss until this is resolved. Fixes: 8f1880cbe8d0 ("net: dsa: bcm_sf2: Configure IMP port for 2Gb/sec") Fixes: de34d7084edd ("net: dsa: bcm_sf2: Only 7278 supports 2Gb/sec IMP port") Signed-off-by: Florian Fainelli <f.fainelli@gmail.com> Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
We are still experiencing some packet loss with the existing advanced
congestion buffering (ACB) settings with the IMP port configured for
2Gb/sec, so revert to conservative link speeds that do not produce
packet loss until this is resolved.

Fixes: 8f1880cbe8d0 ("net: dsa: bcm_sf2: Configure IMP port for 2Gb/sec")
Fixes: de34d7084edd ("net: dsa: bcm_sf2: Only 7278 supports 2Gb/sec IMP port")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Vivien Didelot <vivien.didelot@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>