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    arm64: dts: rockchip: remove vdd_log from rock960 to fix a stability issues · 13682e52
    Daniel Lezcano authored
    When the performance governor is set as default, the rock960 hangs
    around one minute after booting, whatever the activity is (idle, key
    pressed, loaded, ...).
    
    Based on the commit log found at https://patchwork.kernel.org/patch/10092377/
    
    "vdd_log has no consumer and therefore will not be set to a specific
    voltage. Still the PWM output pin gets configured and thence the vdd_log
    output voltage will changed from it's default. Depending on the idle
    state of the PWM this will slightly over or undervoltage the logic supply
    of the RK3399 and cause instability with GbE (undervoltage) and PCIe
    (overvoltage). Since the default value set by a voltage divider is the
    correct supply voltage and we don't need to change it during runtime we
    remove the rail from the devicetree completely so the PWM pin will not
    be configured."
    
    After removing the vdd-log from the rock960's specific DT, the board
    does no longer hang and shows a stable behavior.
    
    Apply the same change for the rock960 by removing the vdd-log from the
    DT.
    
    Fixes: 874846f1
    
     ("arm64: dts: rockchip: add 96boards RK3399 Ficus board")
    Cc: stable@vger.kernel.org
    Tested-by: default avatarManivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
    Signed-off-by: default avatarDaniel Lezcano <daniel.lezcano@linaro.org>
    Signed-off-by: default avatarHeiko Stuebner <heiko@sntech.de>
    13682e52