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[ Upstream commita49d2a2c37] The max_adj field in ptp_clock_info tells userspace how much the PHC clock frequency can be adjusted. ptp4l reads this and will never request a correction larger than max_adj. On both sparx5 and lan969x the clock offset may never converge because the servo needs a frequency correction larger than the current max_adj of 200000 (200 ppm) allows. The servo rails at the max and the offset stays in the tens of microseconds. The hardware has no inherent max adjustment limit; frequency correction is done by writing a 64-bit clock period increment to CLK_PER_CFG, and the register has plenty of range. The 200000 value was just an overly conservative software limit. The max_adj is shared between sparx5 and lan969x, and the increased value is safe for both. Fix this by increasing max_adj to 10000000 (10000 ppm), giving the servo sufficient headroom. Fixes:0933bd0404("net: sparx5: Add support for ptp clocks") Signed-off-by: Daniel Machon <daniel.machon@microchip.com> Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com> Link: https://patch.msgid.link/20260212-sparx5-ptp-max-adj-v2-v1-1-06b200e50ce3@microchip.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>