<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/net/phy, branch v5.4.299</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>net: phy: smsc: add proper reset flags for LAN8710A</title>
<updated>2025-08-28T14:21:29+00:00</updated>
<author>
<name>Buday Csaba</name>
<email>buday.csaba@prolan.hu</email>
</author>
<published>2025-07-28T15:29:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a69c5d81d2ce738155480a0f9a27c4473a0951ac'/>
<id>a69c5d81d2ce738155480a0f9a27c4473a0951ac</id>
<content type='text'>
[ Upstream commit 57ec5a8735dc5dccd1ee68afdb1114956a3fce0d ]

According to the LAN8710A datasheet (Rev. B, section 3.8.5.1), a hardware
reset is required after power-on, and the reference clock (REF_CLK) must be
established before asserting reset.

Signed-off-by: Buday Csaba &lt;buday.csaba@prolan.hu&gt;
Cc: Csókás Bence &lt;csokas.bence@prolan.hu&gt;
Reviewed-by: Andrew Lunn &lt;andrew@lunn.ch&gt;
Link: https://patch.msgid.link/20250728152916.46249-2-csokas.bence@prolan.hu
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 57ec5a8735dc5dccd1ee68afdb1114956a3fce0d ]

According to the LAN8710A datasheet (Rev. B, section 3.8.5.1), a hardware
reset is required after power-on, and the reference clock (REF_CLK) must be
established before asserting reset.

Signed-off-by: Buday Csaba &lt;buday.csaba@prolan.hu&gt;
Cc: Csókás Bence &lt;csokas.bence@prolan.hu&gt;
Reviewed-by: Andrew Lunn &lt;andrew@lunn.ch&gt;
Link: https://patch.msgid.link/20250728152916.46249-2-csokas.bence@prolan.hu
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: phy: microchip: limit 100M workaround to link-down events on LAN88xx</title>
<updated>2025-07-17T16:25:04+00:00</updated>
<author>
<name>Oleksij Rempel</name>
<email>o.rempel@pengutronix.de</email>
</author>
<published>2025-07-09T13:07:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=7c0beeab3a3003811a54e44abfe1bfe576f020ff'/>
<id>7c0beeab3a3003811a54e44abfe1bfe576f020ff</id>
<content type='text'>
[ Upstream commit dd4360c0e8504f2f7639c7f5d07c93cfd6a98333 ]

Restrict the 100Mbit forced-mode workaround to link-down transitions
only, to prevent repeated link reset cycles in certain configurations.

The workaround was originally introduced to improve signal reliability
when switching cables between long and short distances. It temporarily
forces the PHY into 10 Mbps before returning to 100 Mbps.

However, when used with autonegotiating link partners (e.g., Intel i350),
executing this workaround on every link change can confuse the partner
and cause constant renegotiation loops. This results in repeated link
down/up transitions and the PHY never reaching a stable state.

Limit the workaround to only run during the PHY_NOLINK state. This ensures
it is triggered only once per link drop, avoiding disruptive toggling
while still preserving its intended effect.

Note: I am not able to reproduce the original issue that this workaround
addresses. I can only confirm that 100 Mbit mode works correctly in my
test setup. Based on code inspection, I assume the workaround aims to
reset some internal state machine or signal block by toggling speeds.
However, a PHY reset is already performed earlier in the function via
phy_init_hw(), which may achieve a similar effect. Without a reproducer,
I conservatively keep the workaround but restrict its conditions.

Fixes: e57cf3639c32 ("net: lan78xx: fix accessing the LAN7800's internal phy specific registers from the MAC driver")
Signed-off-by: Oleksij Rempel &lt;o.rempel@pengutronix.de&gt;
Reviewed-by: Andrew Lunn &lt;andrew@lunn.ch&gt;
Link: https://patch.msgid.link/20250709130753.3994461-3-o.rempel@pengutronix.de
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit dd4360c0e8504f2f7639c7f5d07c93cfd6a98333 ]

Restrict the 100Mbit forced-mode workaround to link-down transitions
only, to prevent repeated link reset cycles in certain configurations.

The workaround was originally introduced to improve signal reliability
when switching cables between long and short distances. It temporarily
forces the PHY into 10 Mbps before returning to 100 Mbps.

However, when used with autonegotiating link partners (e.g., Intel i350),
executing this workaround on every link change can confuse the partner
and cause constant renegotiation loops. This results in repeated link
down/up transitions and the PHY never reaching a stable state.

Limit the workaround to only run during the PHY_NOLINK state. This ensures
it is triggered only once per link drop, avoiding disruptive toggling
while still preserving its intended effect.

Note: I am not able to reproduce the original issue that this workaround
addresses. I can only confirm that 100 Mbit mode works correctly in my
test setup. Based on code inspection, I assume the workaround aims to
reset some internal state machine or signal block by toggling speeds.
However, a PHY reset is already performed earlier in the function via
phy_init_hw(), which may achieve a similar effect. Without a reproducer,
I conservatively keep the workaround but restrict its conditions.

Fixes: e57cf3639c32 ("net: lan78xx: fix accessing the LAN7800's internal phy specific registers from the MAC driver")
Signed-off-by: Oleksij Rempel &lt;o.rempel@pengutronix.de&gt;
Reviewed-by: Andrew Lunn &lt;andrew@lunn.ch&gt;
Link: https://patch.msgid.link/20250709130753.3994461-3-o.rempel@pengutronix.de
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net/mdiobus: Fix potential out-of-bounds read/write access</title>
<updated>2025-06-27T10:02:50+00:00</updated>
<author>
<name>Jakub Raczynski</name>
<email>j.raczynski@samsung.com</email>
</author>
<published>2025-06-09T15:31:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=ff70bd8ff44fcfb0a3c84b054eca7bcb7d958839'/>
<id>ff70bd8ff44fcfb0a3c84b054eca7bcb7d958839</id>
<content type='text'>
[ Upstream commit 0e629694126ca388916f059453a1c36adde219c4 ]

When using publicly available tools like 'mdio-tools' to read/write data
from/to network interface and its PHY via mdiobus, there is no verification of
parameters passed to the ioctl and it accepts any mdio address.
Currently there is support for 32 addresses in kernel via PHY_MAX_ADDR define,
but it is possible to pass higher value than that via ioctl.
While read/write operation should generally fail in this case,
mdiobus provides stats array, where wrong address may allow out-of-bounds
read/write.

Fix that by adding address verification before read/write operation.
While this excludes this access from any statistics, it improves security of
read/write operation.

Fixes: 080bb352fad00 ("net: phy: Maintain MDIO device and bus statistics")
Signed-off-by: Jakub Raczynski &lt;j.raczynski@samsung.com&gt;
Reported-by: Wenjing Shan &lt;wenjing.shan@samsung.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 0e629694126ca388916f059453a1c36adde219c4 ]

When using publicly available tools like 'mdio-tools' to read/write data
from/to network interface and its PHY via mdiobus, there is no verification of
parameters passed to the ioctl and it accepts any mdio address.
Currently there is support for 32 addresses in kernel via PHY_MAX_ADDR define,
but it is possible to pass higher value than that via ioctl.
While read/write operation should generally fail in this case,
mdiobus provides stats array, where wrong address may allow out-of-bounds
read/write.

Fix that by adding address verification before read/write operation.
While this excludes this access from any statistics, it improves security of
read/write operation.

Fixes: 080bb352fad00 ("net: phy: Maintain MDIO device and bus statistics")
Signed-off-by: Jakub Raczynski &lt;j.raczynski@samsung.com&gt;
Reported-by: Wenjing Shan &lt;wenjing.shan@samsung.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: mdio: C22 is now optional, EOPNOTSUPP if not provided</title>
<updated>2025-06-27T10:02:50+00:00</updated>
<author>
<name>Andrew Lunn</name>
<email>andrew@lunn.ch</email>
</author>
<published>2023-01-09T15:30:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=38c9d4f8e62e3c728e5285e4e6cc82e898ddda71'/>
<id>38c9d4f8e62e3c728e5285e4e6cc82e898ddda71</id>
<content type='text'>
[ Upstream commit b063b1924fd9bf0bc157cf644764dc2151d04ccc ]

When performing a C22 operation, check that the bus driver actually
provides the methods, and return -EOPNOTSUPP if not. C45 only busses
do exist, and in future their C22 methods will be NULL.

Signed-off-by: Andrew Lunn &lt;andrew@lunn.ch&gt;
Signed-off-by: Michael Walle &lt;michael@walle.cc&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Stable-dep-of: 0e629694126c ("net/mdiobus: Fix potential out-of-bounds read/write access")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit b063b1924fd9bf0bc157cf644764dc2151d04ccc ]

When performing a C22 operation, check that the bus driver actually
provides the methods, and return -EOPNOTSUPP if not. C45 only busses
do exist, and in future their C22 methods will be NULL.

Signed-off-by: Andrew Lunn &lt;andrew@lunn.ch&gt;
Signed-off-by: Michael Walle &lt;michael@walle.cc&gt;
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Stable-dep-of: 0e629694126c ("net/mdiobus: Fix potential out-of-bounds read/write access")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: phy: leds: fix memory leak</title>
<updated>2025-05-02T05:39:25+00:00</updated>
<author>
<name>Qingfang Deng</name>
<email>qingfang.deng@siflower.com.cn</email>
</author>
<published>2025-04-17T03:25:56+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=966d6494e2ed9be9052fcd9815afba830896aaf8'/>
<id>966d6494e2ed9be9052fcd9815afba830896aaf8</id>
<content type='text'>
[ Upstream commit b7f0ee992adf601aa00c252418266177eb7ac2bc ]

A network restart test on a router led to an out-of-memory condition,
which was traced to a memory leak in the PHY LED trigger code.

The root cause is misuse of the devm API. The registration function
(phy_led_triggers_register) is called from phy_attach_direct, not
phy_probe, and the unregister function (phy_led_triggers_unregister)
is called from phy_detach, not phy_remove. This means the register and
unregister functions can be called multiple times for the same PHY
device, but devm-allocated memory is not freed until the driver is
unbound.

This also prevents kmemleak from detecting the leak, as the devm API
internally stores the allocated pointer.

Fix this by replacing devm_kzalloc/devm_kcalloc with standard
kzalloc/kcalloc, and add the corresponding kfree calls in the unregister
path.

Fixes: 3928ee6485a3 ("net: phy: leds: Add support for "link" trigger")
Fixes: 2e0bc452f472 ("net: phy: leds: add support for led triggers on phy link state change")
Signed-off-by: Hao Guan &lt;hao.guan@siflower.com.cn&gt;
Signed-off-by: Qingfang Deng &lt;qingfang.deng@siflower.com.cn&gt;
Reviewed-by: Andrew Lunn &lt;andrew@lunn.ch&gt;
Link: https://patch.msgid.link/20250417032557.2929427-1-dqfext@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit b7f0ee992adf601aa00c252418266177eb7ac2bc ]

A network restart test on a router led to an out-of-memory condition,
which was traced to a memory leak in the PHY LED trigger code.

The root cause is misuse of the devm API. The registration function
(phy_led_triggers_register) is called from phy_attach_direct, not
phy_probe, and the unregister function (phy_led_triggers_unregister)
is called from phy_detach, not phy_remove. This means the register and
unregister functions can be called multiple times for the same PHY
device, but devm-allocated memory is not freed until the driver is
unbound.

This also prevents kmemleak from detecting the leak, as the devm API
internally stores the allocated pointer.

Fix this by replacing devm_kzalloc/devm_kcalloc with standard
kzalloc/kcalloc, and add the corresponding kfree calls in the unregister
path.

Fixes: 3928ee6485a3 ("net: phy: leds: Add support for "link" trigger")
Fixes: 2e0bc452f472 ("net: phy: leds: add support for led triggers on phy link state change")
Signed-off-by: Hao Guan &lt;hao.guan@siflower.com.cn&gt;
Signed-off-by: Qingfang Deng &lt;qingfang.deng@siflower.com.cn&gt;
Reviewed-by: Andrew Lunn &lt;andrew@lunn.ch&gt;
Link: https://patch.msgid.link/20250417032557.2929427-1-dqfext@gmail.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: phy: vitesse: repair vsc73xx autonegotiation</title>
<updated>2024-11-08T15:20:24+00:00</updated>
<author>
<name>Pawel Dembicki</name>
<email>paweldembicki@gmail.com</email>
</author>
<published>2024-08-09T19:38:06+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=bd21d96484911829a3927d0afe49142131e2c4ee'/>
<id>bd21d96484911829a3927d0afe49142131e2c4ee</id>
<content type='text'>
[ Upstream commit de7a670f8defe4ed2115552ad23dea0f432f7be4 ]

When the vsc73xx mdio bus work properly, the generic autonegotiation
configuration works well.

Reviewed-by: Linus Walleij &lt;linus.walleij@linaro.org&gt;
Signed-off-by: Pawel Dembicki &lt;paweldembicki@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit de7a670f8defe4ed2115552ad23dea0f432f7be4 ]

When the vsc73xx mdio bus work properly, the generic autonegotiation
configuration works well.

Reviewed-by: Linus Walleij &lt;linus.walleij@linaro.org&gt;
Signed-off-by: Pawel Dembicki &lt;paweldembicki@gmail.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: phy: micrel: add Microchip KSZ 9477 to the device table</title>
<updated>2024-07-05T07:08:27+00:00</updated>
<author>
<name>Enguerrand de Ribaucourt</name>
<email>enguerrand.de-ribaucourt@savoirfairelinux.com</email>
</author>
<published>2024-06-21T14:43:20+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=cb9285617ef03eab3fc6e3c8b79fcf523f015bf3'/>
<id>cb9285617ef03eab3fc6e3c8b79fcf523f015bf3</id>
<content type='text'>
[ Upstream commit 54a4e5c16382e871c01dd82b47e930fdce30406b ]

PHY_ID_KSZ9477 was supported but not added to the device table passed to
MODULE_DEVICE_TABLE.

Fixes: fc3973a1fa09 ("phy: micrel: add Microchip KSZ 9477 Switch PHY support")
Signed-off-by: Enguerrand de Ribaucourt &lt;enguerrand.de-ribaucourt@savoirfairelinux.com&gt;
Reviewed-by: Andrew Lunn &lt;andrew@lunn.ch&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 54a4e5c16382e871c01dd82b47e930fdce30406b ]

PHY_ID_KSZ9477 was supported but not added to the device table passed to
MODULE_DEVICE_TABLE.

Fixes: fc3973a1fa09 ("phy: micrel: add Microchip KSZ 9477 Switch PHY support")
Signed-off-by: Enguerrand de Ribaucourt &lt;enguerrand.de-ribaucourt@savoirfairelinux.com&gt;
Reviewed-by: Andrew Lunn &lt;andrew@lunn.ch&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: phy: mchp: Add support for LAN8814 QUAD PHY</title>
<updated>2024-07-05T07:08:27+00:00</updated>
<author>
<name>Divya Koppera</name>
<email>Divya.Koppera@microchip.com</email>
</author>
<published>2020-09-11T13:18:44+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=3f5e8191a10cc08939e6b62720c2f4ebadae6bde'/>
<id>3f5e8191a10cc08939e6b62720c2f4ebadae6bde</id>
<content type='text'>
[ Upstream commit 1623ad8ec04c771a54975fb84b22bc21c2dbcac1 ]

LAN8814 is a low-power, quad-port triple-speed (10BASE-T/100BASETX/1000BASE-T)
Ethernet physical layer transceiver (PHY). It supports transmission and
reception of data on standard CAT-5, as well as CAT-5e and CAT-6, unshielded
twisted pair (UTP) cables.

LAN8814 supports industry-standard QSGMII (Quad Serial Gigabit Media
Independent Interface) and Q-USGMII (Quad Universal Serial Gigabit Media
Independent Interface) providing chip-to-chip connection to four Gigabit
Ethernet MACs using a single serialized link (differential pair) in each
direction.

The LAN8814 SKU supports high-accuracy timestamping functions to
support IEEE-1588 solutions using Microchip Ethernet switches, as well as
customer solutions based on SoCs and FPGAs.

The LAN8804 SKU has same features as that of LAN8814 SKU except that it does
not support 1588, SyncE, or Q-USGMII with PCH/MCH.

This adds support for 10BASE-T, 100BASE-TX, and 1000BASE-T,
QSGMII link with the MAC.

Signed-off-by: Divya Koppera&lt;divya.koppera@microchip.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Stable-dep-of: 54a4e5c16382 ("net: phy: micrel: add Microchip KSZ 9477 to the device table")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 1623ad8ec04c771a54975fb84b22bc21c2dbcac1 ]

LAN8814 is a low-power, quad-port triple-speed (10BASE-T/100BASETX/1000BASE-T)
Ethernet physical layer transceiver (PHY). It supports transmission and
reception of data on standard CAT-5, as well as CAT-5e and CAT-6, unshielded
twisted pair (UTP) cables.

LAN8814 supports industry-standard QSGMII (Quad Serial Gigabit Media
Independent Interface) and Q-USGMII (Quad Universal Serial Gigabit Media
Independent Interface) providing chip-to-chip connection to four Gigabit
Ethernet MACs using a single serialized link (differential pair) in each
direction.

The LAN8814 SKU supports high-accuracy timestamping functions to
support IEEE-1588 solutions using Microchip Ethernet switches, as well as
customer solutions based on SoCs and FPGAs.

The LAN8804 SKU has same features as that of LAN8814 SKU except that it does
not support 1588, SyncE, or Q-USGMII with PCH/MCH.

This adds support for 10BASE-T, 100BASE-TX, and 1000BASE-T,
QSGMII link with the MAC.

Signed-off-by: Divya Koppera&lt;divya.koppera@microchip.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Stable-dep-of: 54a4e5c16382 ("net: phy: micrel: add Microchip KSZ 9477 to the device table")
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: phy: micrel: populate .soft_reset for KSZ9131</title>
<updated>2024-01-25T22:34:32+00:00</updated>
<author>
<name>Claudiu Beznea</name>
<email>claudiu.beznea.uj@bp.renesas.com</email>
</author>
<published>2024-01-05T08:52:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f7a153e3ac41f9c04ef1bd06c4be6432e93dd664'/>
<id>f7a153e3ac41f9c04ef1bd06c4be6432e93dd664</id>
<content type='text'>
[ Upstream commit e398822c4751017fe401f57409488f5948d12fb5 ]

The RZ/G3S SMARC Module has 2 KSZ9131 PHYs. In this setup, the KSZ9131 PHY
is used with the ravb Ethernet driver. It has been discovered that when
bringing the Ethernet interface down/up continuously, e.g., with the
following sh script:

$ while :; do ifconfig eth0 down; ifconfig eth0 up; done

the link speed and duplex are wrong after interrupting the bring down/up
operation even though the Ethernet interface is up. To recover from this
state the following configuration sequence is necessary (executed
manually):

$ ifconfig eth0 down
$ ifconfig eth0 up

The behavior has been identified also on the Microchip SAMA7G5-EK board
which runs the macb driver and uses the same PHY.

The order of PHY-related operations in ravb_open() is as follows:
ravb_open() -&gt;
  ravb_phy_start() -&gt;
    ravb_phy_init() -&gt;
      of_phy_connect() -&gt;
        phy_connect_direct() -&gt;
	  phy_attach_direct() -&gt;
	    phy_init_hw() -&gt;
	      phydev-&gt;drv-&gt;soft_reset()
	      phydev-&gt;drv-&gt;config_init()
	      phydev-&gt;drv-&gt;config_intr()
	    phy_resume()
	      kszphy_resume()

The order of PHY-related operations in ravb_close is as follows:
ravb_close() -&gt;
  phy_stop() -&gt;
    phy_suspend() -&gt;
      kszphy_suspend() -&gt;
        genphy_suspend()
	  // set BMCR_PDOWN bit in MII_BMCR

In genphy_suspend() setting the BMCR_PDWN bit in MII_BMCR switches the PHY
to Software Power-Down (SPD) mode (according to the KSZ9131 datasheet).
Thus, when opening the interface after it has been  previously closed (via
ravb_close()), the phydev-&gt;drv-&gt;config_init() and
phydev-&gt;drv-&gt;config_intr() reach the KSZ9131 PHY driver via the
ksz9131_config_init() and kszphy_config_intr() functions.

KSZ9131 specifies that the MII management interface remains operational
during SPD (Software Power-Down), but (according to manual):
- Only access to the standard registers (0 through 31) is supported.
- Access to MMD address spaces other than MMD address space 1 is possible
  if the spd_clock_gate_override bit is set.
- Access to MMD address space 1 is not possible.

The spd_clock_gate_override bit is not used in the KSZ9131 driver.

ksz9131_config_init() configures RGMII delay, pad skews and LEDs by
accessesing MMD registers other than those in address space 1.

The datasheet for the KSZ9131 does not specify what happens if registers
from an unsupported address space are accessed while the PHY is in SPD.

To fix the issue the .soft_reset method has been instantiated for KSZ9131,
too. This resets the PHY to the default state before doing any
configurations to it, thus switching it out of SPD.

Fixes: bff5b4b37372 ("net: phy: micrel: add Microchip KSZ9131 initial driver")
Signed-off-by: Claudiu Beznea &lt;claudiu.beznea.uj@bp.renesas.com&gt;
Reviewed-by: Maxime Chevallier &lt;maxime.chevallier@bootlin.com&gt;
Reviewed-by: Andrew Lunn &lt;andrew@lunn.ch&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit e398822c4751017fe401f57409488f5948d12fb5 ]

The RZ/G3S SMARC Module has 2 KSZ9131 PHYs. In this setup, the KSZ9131 PHY
is used with the ravb Ethernet driver. It has been discovered that when
bringing the Ethernet interface down/up continuously, e.g., with the
following sh script:

$ while :; do ifconfig eth0 down; ifconfig eth0 up; done

the link speed and duplex are wrong after interrupting the bring down/up
operation even though the Ethernet interface is up. To recover from this
state the following configuration sequence is necessary (executed
manually):

$ ifconfig eth0 down
$ ifconfig eth0 up

The behavior has been identified also on the Microchip SAMA7G5-EK board
which runs the macb driver and uses the same PHY.

The order of PHY-related operations in ravb_open() is as follows:
ravb_open() -&gt;
  ravb_phy_start() -&gt;
    ravb_phy_init() -&gt;
      of_phy_connect() -&gt;
        phy_connect_direct() -&gt;
	  phy_attach_direct() -&gt;
	    phy_init_hw() -&gt;
	      phydev-&gt;drv-&gt;soft_reset()
	      phydev-&gt;drv-&gt;config_init()
	      phydev-&gt;drv-&gt;config_intr()
	    phy_resume()
	      kszphy_resume()

The order of PHY-related operations in ravb_close is as follows:
ravb_close() -&gt;
  phy_stop() -&gt;
    phy_suspend() -&gt;
      kszphy_suspend() -&gt;
        genphy_suspend()
	  // set BMCR_PDOWN bit in MII_BMCR

In genphy_suspend() setting the BMCR_PDWN bit in MII_BMCR switches the PHY
to Software Power-Down (SPD) mode (according to the KSZ9131 datasheet).
Thus, when opening the interface after it has been  previously closed (via
ravb_close()), the phydev-&gt;drv-&gt;config_init() and
phydev-&gt;drv-&gt;config_intr() reach the KSZ9131 PHY driver via the
ksz9131_config_init() and kszphy_config_intr() functions.

KSZ9131 specifies that the MII management interface remains operational
during SPD (Software Power-Down), but (according to manual):
- Only access to the standard registers (0 through 31) is supported.
- Access to MMD address spaces other than MMD address space 1 is possible
  if the spd_clock_gate_override bit is set.
- Access to MMD address space 1 is not possible.

The spd_clock_gate_override bit is not used in the KSZ9131 driver.

ksz9131_config_init() configures RGMII delay, pad skews and LEDs by
accessesing MMD registers other than those in address space 1.

The datasheet for the KSZ9131 does not specify what happens if registers
from an unsupported address space are accessed while the PHY is in SPD.

To fix the issue the .soft_reset method has been instantiated for KSZ9131,
too. This resets the PHY to the default state before doing any
configurations to it, thus switching it out of SPD.

Fixes: bff5b4b37372 ("net: phy: micrel: add Microchip KSZ9131 initial driver")
Signed-off-by: Claudiu Beznea &lt;claudiu.beznea.uj@bp.renesas.com&gt;
Reviewed-by: Maxime Chevallier &lt;maxime.chevallier@bootlin.com&gt;
Reviewed-by: Andrew Lunn &lt;andrew@lunn.ch&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>net: phy: broadcom: stub c45 read/write for 54810</title>
<updated>2023-08-30T14:27:20+00:00</updated>
<author>
<name>Justin Chen</name>
<email>justin.chen@broadcom.com</email>
</author>
<published>2023-08-13T04:41:47+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=fce08155529307df5a1970efb87868df2b9ec237'/>
<id>fce08155529307df5a1970efb87868df2b9ec237</id>
<content type='text'>
commit 096516d092d54604d590827d05b1022c8f326639 upstream.

The 54810 does not support c45. The mmd_phy_indirect accesses return
arbirtary values leading to odd behavior like saying it supports EEE
when it doesn't. We also see that reading/writing these non-existent
MMD registers leads to phy instability in some cases.

Fixes: b14995ac2527 ("net: phy: broadcom: Add BCM54810 PHY entry")
Signed-off-by: Justin Chen &lt;justin.chen@broadcom.com&gt;
Reviewed-by: Florian Fainelli &lt;florian.fainelli@broadcom.com&gt;
Link: https://lore.kernel.org/r/1691901708-28650-1-git-send-email-justin.chen@broadcom.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
[florian: resolved conflicts in 5.4]
Signed-off-by: Florian Fainelli &lt;florian.fainelli@broadcom.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 096516d092d54604d590827d05b1022c8f326639 upstream.

The 54810 does not support c45. The mmd_phy_indirect accesses return
arbirtary values leading to odd behavior like saying it supports EEE
when it doesn't. We also see that reading/writing these non-existent
MMD registers leads to phy instability in some cases.

Fixes: b14995ac2527 ("net: phy: broadcom: Add BCM54810 PHY entry")
Signed-off-by: Justin Chen &lt;justin.chen@broadcom.com&gt;
Reviewed-by: Florian Fainelli &lt;florian.fainelli@broadcom.com&gt;
Link: https://lore.kernel.org/r/1691901708-28650-1-git-send-email-justin.chen@broadcom.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
[florian: resolved conflicts in 5.4]
Signed-off-by: Florian Fainelli &lt;florian.fainelli@broadcom.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
