linux.git/drivers/net/phy/micrel.c, branch v5.8

net: phy: micrel: add phy-mode support for the KSZ9031 PHY

2020-04-23T02:38:46+00:00

Add support for following phy-modes: rgmii, rgmii-id, rgmii-txid, rgmii-rxid.

This PHY has an internal RX delay of 1.2ns and no delay for TX.

The pad skew registers allow to set the total TX delay to max 1.38ns and
the total RX delay to max of 2.58ns (configurable 1.38ns + build in
1.2ns) and a minimal delay of 0ns.

According to the RGMII v1.3 specification the delay provided by PCB traces
should be between 1.5ns and 2.0ns. The RGMII v2.0 allows to provide this
delay by MAC or PHY. So, we configure this PHY to the best values we can
get by this HW: TX delay to 1.38ns (max supported value) and RX delay to
1.80ns (best calculated delay)

The phy-modes can still be fine tuned/overwritten by *-skew-ps
device tree properties described in:
Documentation/devicetree/bindings/net/micrel-ksz90x1.txt

Signed-off-by: Oleksij Rempel 
Reviewed-by: Philippe Schenker 
Reviewed-by: Andrew Lunn 
Signed-off-by: David S. Miller

net: phy: micrel: use genphy_read_status for KSZ9131

2020-04-14T23:25:30+00:00

KSZ9131 will not work with some switches due to workaround for KSZ9031
introduced in commit d2fd719bcb0e83cb39cfee22ee800f98a56eceb3
("net/phy: micrel: Add workaround for bad autoneg").
Use genphy_read_status instead of dedicated ksz9031_read_status.

Fixes: bff5b4b37372 ("net: phy: micrel: add Microchip KSZ9131 initial driver")
Signed-off-by: Atsushi Nemoto 
Signed-off-by: David S. Miller

net: phy: micrel: kszphy_resume(): add delay after genphy_resume() before accessing PHY registers

2020-04-03T23:04:24+00:00

After the power-down bit is cleared, the chip internally triggers a
global reset. According to the KSZ9031 documentation, we have to wait at
least 1ms for the reset to finish.

If the chip is accessed during reset, read will return 0xffff, while
write will be ignored. Depending on the system performance and MDIO bus
speed, we may or may not run in to this issue.

This bug was discovered on an iMX6QP system with KSZ9031 PHY and
attached PHY interrupt line. If IRQ was used, the link status update was
lost. In polling mode, the link status update was always correct.

The investigation showed, that during a read-modify-write access, the
read returned 0xffff (while the chip was still in reset) and
corresponding write hit the chip _after_ reset and triggered (due to the
0xffff) another reset in an undocumented bit (register 0x1f, bit 1),
resulting in the next write being lost due to the new reset cycle.

This patch fixes the issue by adding a 1...2 ms sleep after the
genphy_resume().

Fixes: 836384d2501d ("net: phy: micrel: Add specific suspend")
Signed-off-by: Oleksij Rempel 
Reviewed-by: Andrew Lunn 
Reviewed-by: Florian Fainelli 
Signed-off-by: David S. Miller

net: phy: micrel.c: add rgmii interface delay possibility to ksz9131

2020-03-30T04:44:26+00:00

The KSZ9131 provides DLL controlled delays on RXC and TXC lines. This
patch makes use of those delays. The information which delays should
be enabled or disabled comes from the interface names, documented in
ethernet-controller.yaml:

rgmii:      Disable RXC and TXC delays
rgmii-id:   Enable RXC and TXC delays
rgmii-txid: Enable only TXC delay, disable RXC delay
rgmii-rxid: Enable onlx RXC delay, disable TXC delay

Signed-off-by: Philippe Schenker 
Signed-off-by: David S. Miller

net: phy: micrel: Update KSZ87xx PHY name

2019-10-17T23:31:52+00:00

The KSZ8795 PHY ID is in fact used by KSZ8794/KSZ8795/KSZ8765 switches.
Update the PHY ID and name to reflect that, as this family of switches
is commonly refered to as KSZ87xx

Signed-off-by: Marek Vasut 
Cc: Andrew Lunn 
Cc: David S. Miller 
Cc: Florian Fainelli 
Cc: George McCollister 
Cc: Heiner Kallweit 
Cc: Sean Nyekjaer 
Cc: Tristram Ha 
Cc: Woojung Huh 
Signed-off-by: David S. Miller

net: phy: micrel: Discern KSZ8051 and KSZ8795 PHYs

2019-10-17T23:31:51+00:00

The KSZ8051 PHY and the KSZ8794/KSZ8795/KSZ8765 switch share exactly the
same PHY ID. Since KSZ8051 is higher in the ksphy_driver[] list of PHYs
in the micrel PHY driver, it is used even with the KSZ87xx switch. This
is wrong, since the KSZ8051 configures registers of the PHY which are
not present on the simplified KSZ87xx switch PHYs and misconfigures
other registers of the KSZ87xx switch PHYs.

Fortunatelly, it is possible to tell apart the KSZ8051 PHY from the
KSZ87xx switch by checking the Basic Status register Bit 0, which is
read-only and indicates presence of the Extended Capability Registers.
The KSZ8051 PHY has those registers while the KSZ87xx switch does not.

This patch implements simple check for the presence of this bit for
both the KSZ8051 PHY and KSZ87xx switch, to let both use the correct
PHY driver instance.

Fixes: 9d162ed69f51 ("net: phy: micrel: add support for KSZ8795")
Signed-off-by: Marek Vasut 
Cc: Andrew Lunn 
Cc: David S. Miller 
Cc: Florian Fainelli 
Cc: George McCollister 
Cc: Heiner Kallweit 
Cc: Sean Nyekjaer 
Cc: Tristram Ha 
Cc: Woojung Huh 
Signed-off-by: David S. Miller

net: phy: micrel: add Asym Pause workaround for KSZ9021

2019-09-27T18:27:26+00:00

The Micrel KSZ9031 PHY may fail to establish a link when the Asymmetric
Pause capability is set. This issue is described in a Silicon Errata
(DS80000691D or DS80000692D), which advises to always disable the
capability.

Micrel KSZ9021 has no errata, but has the same issue with Asymmetric Pause.
This patch apply the same workaround as the one for KSZ9031.

Fixes: 3aed3e2a143c ("net: phy: micrel: add Asym Pause workaround")
Signed-off-by: Hans Andersson 
Reviewed-by: Andrew Lunn 
Signed-off-by: David S. Miller

net: phy: micrel: make sure the factory test bit is cleared

2019-04-30T03:17:21+00:00

The KSZ8081 PHY has a factory test mode which is set at the de-assertion
of the reset line based on the RXER (KSZ8081RNA/RND) or TXC
(KSZ8081MNX/RNB) pin. If a pull-down is missing, or if the pin has a
pull-up, the factory test mode should be cleared by manually writing a 0
(according to the datasheet). This patch makes sure this factory test
bit is cleared in config_init().

Tested-by: Alexandre Belloni 
Signed-off-by: Antoine Tenart 
Reviewed-by: Andrew Lunn 
Signed-off-by: David S. Miller

net: phy: micrel: add Asym Pause workaround

2019-04-17T04:36:40+00:00

The Micrel KSZ9031 PHY may fail to establish a link when the Asymmetric
Pause capability is set. This issue is described in a Silicon Errata
(DS80000691D or DS80000692D), which advises to always disable the
capability. This patch implements the workaround by defining a KSZ9031
specific get_feature callback to force the Asymmetric Pause capability
bit to be cleared.

This fixes issues where the link would not come up at boot time, or when
the Asym Pause bit was set later on.

Signed-off-by: Antoine Tenart 
Reviewed-by: Andrew Lunn 
Reviewed-by: Florian Fainelli 
Signed-off-by: David S. Miller

net: phy: switch drivers to use dynamic feature detection

2019-04-16T00:19:54+00:00

Recently genphy_read_abilities() has been added that dynamically detects
clause 22 PHY abilities. I *think* this detection should work with all
supported PHY's, at least for the ones with basic features sets, i.e.
PHY_BASIC_FEATURES and PHY_GBIT_FEATURES. So let's remove setting these
features explicitly and rely on phylib feature detection.

I don't have access to most of these PHY's, therefore I'd appreciate
regression testing.

v2:
- make the feature constant a comment so that readers know which
  features are supported by the respective PHY

Signed-off-by: Heiner Kallweit 
Tested-by: Andrew Lunn 
Signed-off-by: David S. Miller