• Dien Pham's avatar
    arm64: dts: renesas: r8a7795: Create thermal zone to support IPA · 15d8cd83
    Dien Pham authored
    Setup a thermal zone driven by SoC temperature sensor.
    Create passive trip points and bind them to CPUFreq cooling
    device that supports power extension.
    
    In R-Car Gen3, IPA is supported for only one channel
    (on H3/M3/M3N SoCs, it is channel THS3). Reason:
      Currently, IPA controls base on only CPU temperature.
      And only one thermal channel is assembled closest
      CPU cores is selected as target of IPA.
      If other channels are used, IPA controlling is not properly.
    
    The A5 cooling device supports 5 cooling states which can be categorised as
    follows:
    
    0 & 1) boost (clocking up)
    2)     default
    3 & 4) cooling (clocking down)
    
    Currently the thermal framework assumes that the default is the minimum,
    or in other words there is no provision for handling boost states.
    So this patch only describes the upper 3 states, default and cooling.
    
    A single cooling device is described for all A57 CPUs and a separate
    cooling device is described for all A53 CPUs. This reflects that physically
    there is only one cooling device present for each type of CPU.
    
    This patch improves on an earlier version by:
    
    * Omitting cooling-max-level and cooling-min-level properties which
      are no longer present in mainline as of v4.17
    * Removing an unused trip-point0 node sub-property from the trips
      property.
    * Using cooling-device indexes such that maximum refers to maximum cooling
      rather than the inverse.
    * Defers adding dynamic-power-coefficient properties to a separate patch as
      these are properties of the CPU.
    
    The long signed-off by chain below reflects many revisions, mainly
    internal, that this patch has been through.
    Signed-off-by: default avatarDien Pham <dien.pham.ry@renesas.com>
    Signed-off-by: default avatarKeita Kobayashi <keita.kobayashi.ym@renesas.com>
    Signed-off-by: default avatarGaku Inami <gaku.inami.xw@bp.renesas.com>
    Signed-off-by: default avatarHien Dang <hien.dang.eb@rvc.renesas.com>
    Signed-off-by: default avatarAn Huynh <an.huynh.uj@rvc.renesas.com>
    Signed-off-by: default avatarTakeshi Kihara <takeshi.kihara.df@renesas.com>
    Signed-off-by: default avatarYoshihiro Kaneko <ykaneko0929@gmail.com>
    Signed-off-by: default avatarSimon Horman <horms+renesas@verge.net.au>
    15d8cd83
r8a7795.dtsi 87.5 KB