Russell King db2eabff57 phy: armada-38x: fix NETA lockup when repeatedly switching speeds ... [ Upstream commit 1dea06cd64 ] The mvneta hardware appears to lock up in various random ways when repeatedly switching speeds between 1G and 2.5G, which involves reprogramming the COMPHY. It is not entirely clear why this happens, but best guess is that reprogramming the COMPHY glitches mvneta clocks causing the hardware to fail. It seems that rebooting resolves the failure, but not down/up cycling the interface alone. Various other approaches have been tried, such as trying to cleanly power down the COMPHY and then take it back through the power up initialisation, but this does not seem to help. It was finally noticed that u-boot's last step when configuring a COMPHY for "SGMII" mode was to poke at a register described as "GBE_CONFIGURATION_REG", which is undocumented in any external documentation. All that we have is the fact that u-boot sets a bit corresponding to the "SGMII" lane at the end of COMPHY initialisation. Experimentation shows that if we clear this bit prior to changing the speed, and then set it afterwards, mvneta does not suffer this problem on the SolidRun Clearfog when switching speeds between 1G and 2.5G. This problem was found while script-testing phylink. This fix also requires the corresponding change to DT to be effective. See "ARM: dts: armada-38x: fix NETA lockup when repeatedly switching speeds". Fixes: 14dc100b44 ("phy: armada38x: add common phy support") Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk> Reviewed-by: Andrew Lunn <andrew@lunn.ch> Link: https://lore.kernel.org/r/E1jxtRj-0003Tz-CG@rmk-PC.armlinux.org.uk Signed-off-by: Vinod Koul <vkoul@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2020-08-19 08:16:14 +02:00
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Kconfig	phy: mvebu-cp110-comphy: Add SMC call support	2019-08-27 11:37:09 +05:30
Makefile	USB/PHY patches for 5.1-rc1	2019-03-06 16:48:27 -08:00
phy-armada38x-comphy.c	phy: armada-38x: fix NETA lockup when repeatedly switching speeds	2020-08-19 08:16:14 +02:00
phy-armada375-usb2.c	phy: armada375-usb2: switch to SPDX license identifier	2019-02-07 11:10:45 +05:30
phy-berlin-sata.c	phy: fix build breakage: add PHY_MODE_SATA	2019-01-16 18:00:54 +05:30
phy-berlin-usb.c	phy: berlin: switch to SPDX license identifier	2018-07-10 13:45:12 +05:30
phy-mvebu-a3700-comphy.c	phy: mvebu-a3700-comphy: Inform users if their firmware is too old	2019-08-23 09:41:00 +05:30
phy-mvebu-a3700-utmi.c	phy: fix platform_no_drv_owner.cocci warnings	2019-04-17 12:06:02 +05:30
phy-mvebu-cp110-comphy.c	phy: marvell: phy-mvebu-cp110-comphy: rename instances of DLT	2019-08-27 11:37:09 +05:30
phy-mvebu-sata.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152	2019-05-30 11:26:32 -07:00
phy-pxa-28nm-hsic.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282	2019-06-05 17:36:37 +02:00
phy-pxa-28nm-usb2.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 282	2019-06-05 17:36:37 +02:00
phy-pxa-usb.c	phy: phy-pxa-usb: add a new driver	2018-10-18 19:44:39 +02:00