rt-thread-official/bsp/imx6sx/cortex-a9/drivers/board.c

82 lines
2.0 KiB
C

/*
* Copyright (c) 2006-2018, RT-Thread Development Team
*
* SPDX-License-Identifier: Apache-2.0
*
* Change Logs:
* Date Author Notes
* 2012-11-20 Bernard the first version
*/
#include <rthw.h>
#include <rtthread.h>
#include "board.h"
#include <registers/regsarmglobaltimer.h>
#include <registers/regsepit.h>
#include <uart/imx_uart.h>
#include <timer/epit.h>
#include <core/cortex_a9.h>
static void rt_hw_timer_isr(int vector, void *param)
{
rt_tick_increase();
epit_get_compare_event(HW_EPIT1);
}
int rt_hw_timer_init(void)
{
uint32_t freq;
// The ARM private peripheral clock is half the CPU clock.
uint32_t periphClock = get_main_clock(CPU_CLK) / 2;
uint32_t prescaler = (periphClock / 1000000) - 1;
// Divide down the prescaler until it fits into 8 bits. We add up the number of ticks
// it takes to equal a microsecond interval.
while (prescaler > 0xff)
{
prescaler /= 2;
}
// Make sure the timer is off.
HW_ARMGLOBALTIMER_CONTROL.B.TIMER_ENABLE = 0;
// Clear counter.
HW_ARMGLOBALTIMER_COUNTERn_WR(0, 0);
HW_ARMGLOBALTIMER_COUNTERn_WR(1, 0);
// Set prescaler and clear other flags.
HW_ARMGLOBALTIMER_CONTROL_WR(BF_ARMGLOBALTIMER_CONTROL_PRESCALER(prescaler));
// Now turn on the timer.
HW_ARMGLOBALTIMER_CONTROL.B.TIMER_ENABLE = 1;
freq = get_main_clock(IPG_CLK);
epit_init(HW_EPIT1, CLKSRC_IPG_CLK, freq / 1000000,
SET_AND_FORGET, 10000, WAIT_MODE_EN | STOP_MODE_EN);
epit_counter_enable(HW_EPIT1, 10000, IRQ_MODE);
rt_hw_interrupt_install(IMX_INT_EPIT1, rt_hw_timer_isr, RT_NULL, "tick");
rt_hw_interrupt_umask(IMX_INT_EPIT1);
return 0;
}
INIT_BOARD_EXPORT(rt_hw_timer_init);
/**
* This function will initialize beaglebone board
*/
void rt_hw_board_init(void)
{
enable_neon_fpu();
disable_strict_align_check();
rt_components_board_init();
rt_console_set_device(RT_CONSOLE_DEVICE_NAME);
}
/*@}*/