hekate/bdk/libs/lvgl/lv_hal/lv_hal_tick.c
CTCaer 185526d134 Introducing Bootloader Development Kit (BDK)
BDK will allow developers to use the full collection of drivers,
with limited editing, if any, for making payloads for Nintendo Switch.

Using a single source for everything will also help decoupling
Switch specific code and easily port it to other Tegra X1/X1+ platforms.
And maybe even to lower targets.

Everything is now centrilized into bdk folder.
Every module or project can utilize it by simply including it.

This is just the start and it will continue to improve.
2020-06-14 15:25:21 +03:00

101 lines
2.1 KiB
C

/**
* @file systick.c
* Provide access to the system tick with 1 millisecond resolution
*/
/*********************
* INCLUDES
*********************/
#ifdef LV_CONF_INCLUDE_SIMPLE
#include "lv_conf.h"
#else
#include "../../lv_conf.h"
#endif
#include "lv_hal_tick.h"
#include <stddef.h>
#if LV_TICK_CUSTOM == 1
#include LV_TICK_CUSTOM_INCLUDE
#endif
/*********************
* DEFINES
*********************/
/**********************
* TYPEDEFS
**********************/
/**********************
* STATIC PROTOTYPES
**********************/
/**********************
* STATIC VARIABLES
**********************/
static uint32_t sys_time = 0;
static volatile uint8_t tick_irq_flag;
/**********************
* MACROS
**********************/
/**********************
* GLOBAL FUNCTIONS
**********************/
/**
* You have to call this function periodically
* @param tick_period the call period of this function in milliseconds
*/
LV_ATTRIBUTE_TICK_INC void lv_tick_inc(uint32_t tick_period)
{
tick_irq_flag = 0;
sys_time += tick_period;
}
/**
* Get the elapsed milliseconds since start up
* @return the elapsed milliseconds
*/
uint32_t lv_tick_get(void)
{
#if LV_TICK_CUSTOM == 0
uint32_t result;
do {
tick_irq_flag = 1;
result = sys_time;
} while(!tick_irq_flag); /*'lv_tick_inc()' clears this flag which can be in an interrupt. Continue until make a non interrupted cycle */
return result;
#else
return LV_TICK_CUSTOM_SYS_TIME_EXPR;
#endif
}
/**
* Get the elapsed milliseconds since a previous time stamp
* @param prev_tick a previous time stamp (return value of systick_get() )
* @return the elapsed milliseconds since 'prev_tick'
*/
uint32_t lv_tick_elaps(uint32_t prev_tick)
{
uint32_t act_time = lv_tick_get();
/*If there is no overflow in sys_time simple subtract*/
if(act_time >= prev_tick) {
prev_tick = act_time - prev_tick;
} else {
prev_tick = UINT32_MAX - prev_tick + 1;
prev_tick += act_time;
}
return prev_tick;
}
/**********************
* STATIC FUNCTIONS
**********************/