rt-thread-official/bsp/at91sam9260/board.c

143 lines
3.4 KiB
C
Executable File

/*
* File : board.c
* This file is part of RT-Thread RTOS
* COPYRIGHT (C) 2006 - 2009 RT-Thread Develop Team
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rt-thread.org/license/LICENSE
*
* Change Logs:
* Date Author Notes
* 2011-01-13 weety first version
*/
#include <rtthread.h>
#include <rthw.h>
#include "board.h"
/**
* @addtogroup at91sam9260
*/
/*@{*/
extern void rt_hw_clock_init(void);
extern void rt_hw_mmu_init(void);
extern void rt_hw_get_clock(void);
extern void rt_hw_set_dividor(rt_uint8_t hdivn, rt_uint8_t pdivn);
extern void rt_hw_set_clock(rt_uint8_t sdiv, rt_uint8_t pdiv, rt_uint8_t mdiv);
extern void rt_dbgu_isr(void);
#define PIT_CPIV(x) ((x) & AT91_PIT_CPIV)
#define PIT_PICNT(x) (((x) & AT91_PIT_PICNT) >> 20)
static rt_uint32_t pit_cycle; /* write-once */
static rt_uint32_t pit_cnt; /* access only w/system irq blocked */
/**
* This function will handle rtos timer
*/
void rt_timer_handler(int vector, void *param)
{
#ifdef RT_USING_DBGU
if (at91_sys_read(AT91_DBGU + AT91_US_CSR) & 0x1)
{
rt_dbgu_isr();
}
#endif
if (at91_sys_read(AT91_PIT_SR) & AT91_PIT_PITS)
{
unsigned nr_ticks;
/* Get number of ticks performed before irq, and ack it */
nr_ticks = PIT_PICNT(at91_sys_read(AT91_PIT_PIVR));
rt_tick_increase();
}
}
static void at91sam926x_pit_reset(void)
{
/* Disable timer and irqs */
at91_sys_write(AT91_PIT_MR, 0);
/* Clear any pending interrupts, wait for PIT to stop counting */
while (PIT_CPIV(at91_sys_read(AT91_PIT_PIVR)) != 0)
;
/* Start PIT but don't enable IRQ */
//at91_sys_write(AT91_PIT_MR, (pit_cycle - 1) | AT91_PIT_PITEN);
pit_cnt += pit_cycle * PIT_PICNT(at91_sys_read(AT91_PIT_PIVR));
at91_sys_write(AT91_PIT_MR, (pit_cycle - 1) | AT91_PIT_PITEN
| AT91_PIT_PITIEN);
rt_kprintf("PIT_MR=0x%08x\n", at91_sys_read(AT91_PIT_MR));
}
/*
* Set up both clocksource and clockevent support.
*/
static void at91sam926x_pit_init(void)
{
rt_uint32_t pit_rate;
rt_uint32_t bits;
/*
* Use our actual MCK to figure out how many MCK/16 ticks per
* 1/HZ period (instead of a compile-time constant LATCH).
*/
pit_rate = clk_get_rate(clk_get("mck")) / 16;
rt_kprintf("pit_rate=%dHZ\n", pit_rate);
pit_cycle = (pit_rate + RT_TICK_PER_SECOND/2) / RT_TICK_PER_SECOND;
/* Initialize and enable the timer */
at91sam926x_pit_reset();
}
/**
* This function will init pit for system ticks
*/
void rt_hw_timer_init()
{
at91sam926x_pit_init();
/* install interrupt handler */
rt_hw_interrupt_install(AT91_ID_SYS, rt_timer_handler,
RT_NULL, "system");
rt_hw_interrupt_umask(AT91_ID_SYS);
}
void at91_tc1_init()
{
at91_sys_write(AT91_PMC_PCER, 1<<AT91SAM9260_ID_TC0);
writel(AT91_TC_TC0XC0S_NONE | AT91_TC_TC1XC1S_NONE | AT91_TC_TC2XC2S_NONE, AT91SAM9260_BASE_TCB0 + AT91_TC_BMR);
writel(AT91_TC_CLKDIS, AT91SAM9260_BASE_TC0 + AT91_TC_CCR);
writel(AT91_TC_TIMER_CLOCK4, AT91SAM9260_BASE_TC0 + AT91_TC_CMR);
writel(0xffff, AT91SAM9260_BASE_TC0 + AT91_TC_CV);
}
/**
* This function will init at91sam9260 board
*/
void rt_hw_board_init()
{
/* initialize the system clock */
rt_hw_clock_init();
/* initialize uart */
rt_hw_uart_init();
rt_console_set_device(RT_CONSOLE_DEVICE_NAME);
/* initialize mmu */
rt_hw_mmu_init();
/* initialize timer0 */
rt_hw_timer_init();
}
/*@}*/