Vladimir Oltean 0322ef49c1 net: dsa: seville: ignore mscc-miim read errors from Lynx PCS ... During the refactoring in the commit below, vsc9953_mdio_read() was replaced with mscc_miim_read(), which has one extra step: it checks for the MSCC_MIIM_DATA_ERROR bits before returning the result. On T1040RDB, there are 8 QSGMII PCSes belonging to the switch, and they are organized in 2 groups. First group responds to MDIO addresses 4-7 because QSGMIIACR1[MDEV_PORT] is 1, and the second group responds to MDIO addresses 8-11 because QSGMIIBCR1[MDEV_PORT] is 2. I have double checked that these values are correctly set in the SERDES, as well as PCCR1[QSGMA_CFG] and PCCR1[QSGMB_CFG] are both 0b01. mscc_miim_read: phyad 8 reg 0x1 MIIM_DATA 0x2d mscc_miim_read: phyad 8 reg 0x5 MIIM_DATA 0x5801 mscc_miim_read: phyad 8 reg 0x1 MIIM_DATA 0x2d mscc_miim_read: phyad 8 reg 0x5 MIIM_DATA 0x5801 mscc_miim_read: phyad 9 reg 0x1 MIIM_DATA 0x2d mscc_miim_read: phyad 9 reg 0x5 MIIM_DATA 0x5801 mscc_miim_read: phyad 9 reg 0x1 MIIM_DATA 0x2d mscc_miim_read: phyad 9 reg 0x5 MIIM_DATA 0x5801 mscc_miim_read: phyad 10 reg 0x1 MIIM_DATA 0x2d mscc_miim_read: phyad 10 reg 0x5 MIIM_DATA 0x5801 mscc_miim_read: phyad 10 reg 0x1 MIIM_DATA 0x2d mscc_miim_read: phyad 10 reg 0x5 MIIM_DATA 0x5801 mscc_miim_read: phyad 11 reg 0x1 MIIM_DATA 0x2d mscc_miim_read: phyad 11 reg 0x5 MIIM_DATA 0x5801 mscc_miim_read: phyad 11 reg 0x1 MIIM_DATA 0x2d mscc_miim_read: phyad 11 reg 0x5 MIIM_DATA 0x5801 mscc_miim_read: phyad 4 reg 0x1 MIIM_DATA 0x3002d, ERROR mscc_miim_read: phyad 4 reg 0x5 MIIM_DATA 0x3da01, ERROR mscc_miim_read: phyad 5 reg 0x1 MIIM_DATA 0x3002d, ERROR mscc_miim_read: phyad 5 reg 0x5 MIIM_DATA 0x35801, ERROR mscc_miim_read: phyad 5 reg 0x1 MIIM_DATA 0x3002d, ERROR mscc_miim_read: phyad 5 reg 0x5 MIIM_DATA 0x35801, ERROR mscc_miim_read: phyad 6 reg 0x1 MIIM_DATA 0x3002d, ERROR mscc_miim_read: phyad 6 reg 0x5 MIIM_DATA 0x35801, ERROR mscc_miim_read: phyad 6 reg 0x1 MIIM_DATA 0x3002d, ERROR mscc_miim_read: phyad 6 reg 0x5 MIIM_DATA 0x35801, ERROR mscc_miim_read: phyad 7 reg 0x1 MIIM_DATA 0x3002d, ERROR mscc_miim_read: phyad 7 reg 0x5 MIIM_DATA 0x35801, ERROR mscc_miim_read: phyad 7 reg 0x1 MIIM_DATA 0x3002d, ERROR mscc_miim_read: phyad 7 reg 0x5 MIIM_DATA 0x35801, ERROR As can be seen, the data in MIIM_DATA is still valid despite having the MSCC_MIIM_DATA_ERROR bits set. The driver as introduced in commit 84705fc165 ("net: dsa: felix: introduce support for Seville VSC9953 switch") was ignoring these bits, perhaps deliberately (although unbeknownst to me). This is an old IP and the hardware team cannot seem to be able to help me track down a plausible reason for these failures. I'll keep investigating, but in the meantime, this is a direct regression which must be restored to a working state. The only thing I can do is keep ignoring the errors as before. Fixes: b996584523 ("net: dsa: ocelot: felix: utilize shared mscc-miim driver for indirect MDIO access") Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com> Reviewed-by: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>		2023-02-26 18:31:37 +00:00
..
mdio-i2c.h	net: phy: mdio-i2c: support I2C MDIO protocol for RollBall SFP modules	2022-10-03 11:08:33 +01:00
mdio-mscc-miim.h	net: dsa: seville: ignore mscc-miim read errors from Lynx PCS	2023-02-26 18:31:37 +00:00
mdio-xgene.h	add missing includes and forward declarations to networking includes under linux/	2022-07-28 11:29:36 +02:00