Hi Badal, [...] > +/* > + * xe_hwmon_energy_get - Obtain energy value > + * > + * The underlying energy hardware register is 32-bits and is subject to > + * overflow. How long before overflow? For example, with an example > + * scaling bit shift of 14 bits (see register *PACKAGE_POWER_SKU_UNIT) and > + * a power draw of 1000 watts, the 32-bit counter will overflow in > + * approximately 4.36 minutes. > + * > + * Examples: > + * 1 watt: (2^32 >> 14) / 1 W / (60 * 60 * 24) secs/day -> 3 days > + * 1000 watts: (2^32 >> 14) / 1000 W / 60 secs/min -> 4.36 minutes > + * > + * The function significantly increases overflow duration (from 4.36 > + * minutes) by accumulating the energy register into a 'long' as allowed by > + * the hwmon API. Using x86_64 128 bit arithmetic (see mul_u64_u32_shr()), > + * a 'long' of 63 bits, SF_ENERGY of 1e6 (~20 bits) and > + * hwmon->scl_shift_energy of 14 bits we have 57 (63 - 20 + 14) bits before > + * energy1_input overflows. This at 1000 W is an overflow duration of 278 years. > + */ > +static void > +xe_hwmon_energy_get(struct xe_hwmon *hwmon, long *energy) can we call it rather xe_hwmon_energy_update() as this is not sending anything, but just updating the energy values. Anyway... Reviewed-by: Andi Shyti <andi.shyti@xxxxxxxxxxxxxxx> Andi
