• Ravikumar Kattekola's avatar
    ARM: dts: dra7: Reduce cpu thermal shutdown temperature · bca52388
    Ravikumar Kattekola authored
    On dra7, as per TRM, the HW shutdown (TSHUT) temperature is hardcoded
    to 123C and cannot be modified by SW. This means when the temperature
    reaches 123C HW asserts TSHUT output which signals a warm reset.
    This reset is held until the temperature goes below the TSHUT low (105C).
    While in SW, the thermal driver continuously monitors current temperature
    and takes decisions based on whether it reached an alert or a critical point.
    The intention of setting a SW critical point is to prevent force reset by HW
    and instead do an orderly_poweroff(). But if the SW critical temperature is
    greater than or equal to that of HW then it defeats the purpose. To address
    this and let SW take action before HW does keep the SW critical temperature
    less than HW TSHUT value.
    The value for SW critical temperature was chosen as 120C just to ensure
    we give SW sometime before HW catches up.
    Document reference
    SPRUI30C – DRA75x, DRA74x Technical Reference Manual - November 2016
    SPRUHZ6H - AM572x Technical Reference Manual - November 2016
    Tested on:
    DRA75x PG 2.0 Rev H EVM
    Signed-off-by: default avatarRavikumar Kattekola <rk@ti.com>
    Signed-off-by: default avatarTony Lindgren <tony@atomide.com>
dra7.dtsi 52.6 KB