• Masahiro Yamada's avatar
    ARM: uniphier: fix glitch signal problem for low-level debug · fcbcd597
    Masahiro Yamada authored
    
    
    Currently, IECTRL is enabled after pin-mux settings for the low-level
    debugging for PH1-LD4 and PH1-sLD8.  While IECTRL is disabled, input
    signals are pulled-down, i.e. glitch signal (Low to High transition)
    problem occurs if pin-mux is set up first.  As a result, one invalid
    character is input to the UART block and the auto-boot counting is
    terminated immediately.
    
    The correct initialization procedure is:
     [1] Enable IECTRL (if IECTRL exists for the pins)
     [2] Set up pin-muxing
     [3] Deassert the reset of the hardware block
    
    Currently, the low-level debugging is working for PH1-sLD3 and
    PH1-Pro4, but just in case, follow the sequence for all the SoCs.
    
    Signed-off-by: default avatarMasahiro Yamada <yamada.masahiro@socionext.com>
    fcbcd597