diff options
| author | Petri Savolainen <petri.savolainen@nokia.com> | 2023-05-22 15:15:13 +0300 |
|---|---|---|
| committer | Petri Savolainen <petri.savolainen@nokia.com> | 2023-06-08 11:05:46 +0300 |
| commit | a94dd9160c9f8d30d2eec45fe11a65e5d8adf2e8 (patch) | |
| tree | 42ce49252593acb3be278a3a19b6ab499d8e32fd | |
| parent | b6db9f2bcf367e3a18051360d8b4d7ab0f767760 (diff) | |
api: timer: clarify base frequency format
Clarify that periodic timer base frequency uses fractional
numbers the same way as timer tick info (odp_timer_tick_info_t).
Integer part specifies full hertz and fractional part specifies
parts of a hertz.
Signed-off-by: Petri Savolainen <petri.savolainen@nokia.com>
Reviewed-by: Matias Elo <matias.elo@nokia.com>
Reviewed-by: Shijith Thotton <sthotton@marvell.com>
| -rw-r--r-- | include/odp/api/spec/timer_types.h | 16 |
1 files changed, 13 insertions, 3 deletions
diff --git a/include/odp/api/spec/timer_types.h b/include/odp/api/spec/timer_types.h index 933e3fd87..97b548116 100644 --- a/include/odp/api/spec/timer_types.h +++ b/include/odp/api/spec/timer_types.h @@ -1,5 +1,5 @@ /* Copyright (c) 2013-2018, Linaro Limited - * Copyright (c) 2019-2022, Nokia + * Copyright (c) 2019-2023, Nokia * * All rights reserved. * @@ -102,7 +102,15 @@ typedef struct { * Periodic timer capability */ typedef struct { - /** Periodic timer pool base frequency in hertz */ + /** + * Periodic timer pool base frequency in hertz + * + * Base frequency is represented as a fractional number where the fraction part is always + * less than one. In other words, the integer part specifies whole hertz whereas + * the fraction part specifies parts of a hertz (if any). The fraction part does not + * need to be reduced to its lowest terms - e.g. 100.5 Hz may be represented as 100 1/2 Hz, + * 100 5/10 Hz, or 100 Hz with some other equivalent fraction part. + */ odp_fract_u64_t base_freq_hz; /** Maximum base frequency multiplier */ @@ -358,7 +366,9 @@ typedef struct { * Use odp_timer_periodic_capability() to check base frequency support, * and resulting max_multiplier and resolution values. * - * The default value is zero. + * Fraction part of the value is always less than one, see + * odp_timer_periodic_capability_t::base_freq_hz for details. The default value + * is zero. * * An example with two timer frequencies: * base_freq_hz.integer = 33333, .numer = 1, .denom = 3 |