Merge branch 'net-dsa-mv88e6xxx-accelerate-c45-scan'
Klaus Kudielka says: ==================== net: dsa: mv88e6xxx: accelerate C45 scan Starting with commit 1a136ca2 ("net: mdio: scan bus based on bus capabilities for C22 and C45"), mdiobus_scan_bus_c45() is being called on buses with MDIOBUS_NO_CAP. On a Turris Omnia (Armada 385, 88E6176 switch), this causes a significant increase of boot time, from 1.6 seconds, to 6.3 seconds. The boot time stated here is until start of /init. Further testing revealed that the C45 scan is indeed expensive (around 2.7 seconds, due to a huge number of bus transactions), and called twice. Two things were suggested: (1) to move the expensive call of mv88e6xxx_mdios_register() from mv88e6xxx_probe() to mv88e6xxx_setup(). (2) to mask apparently non-existing phys during probing. Before that: Patch #1 prepares the driver to handle the movement of mv88e6xxx_mdios_register() to mv88e6xxx_setup() for cross-chip DSA trees. Patch #2 is preparatory code movement, without functional change. With those changes, boot time on the Turris Omnia is back to normal. Link: https://lore.kernel.org/lkml/449bde236c08d5ab5e54abd73b645d8b29955894.camel@gmail.com/ ==================== Link: https://lore.kernel.org/r/20230315163846.3114-1-klaus.kudielka@gmail.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>
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