Function timer_int_init

bsp/loongson/ls1cdev/libraries/ls1c_timer.c:257–301

* ��ʼ����ʱ��������ʼ�ж϶�ʱ * @timer_info ��ʱ���Ͷ�ʱʱ����Ϣ * @hrc ���ж� lrc ���ж� Ϊ1�򿪣�Ϊ0�ر� */

 * @hrc ���ж� lrc ���ж� Ϊ1�򿪣�Ϊ0�ر�
*/
void timer_int_init(timer_info_t *timer_info, int hrc, int lrc)
{
    unsigned int timer_reg_base = 0;        // �Ĵ�������ַ
    unsigned long timer_clk = 0;            // Ӳ����ʱ����ʱ��
    unsigned long h_value, l_value;
    unsigned int ctrl = 0;                  // ���ƼĴ����еĿ�����Ϣ
    
    // ����
    if (NULL == timer_info)
    {
        return ;
    }

    /*
     * �Ѷ�ʱʱ�任��Ϊ��������ֵ
     * ������ֵ = ��ʱ����ʱ�� * ��ʱʱ��(��λns) / 1000000000
     * ��о1c�Ķ�ʱ��ʱ��ΪAPBʱ�ӣ��ﵽ126Mhz��
     * Ϊ���������̷����������������ֶ��Ż�����ļ���ʽ��Ҳ���Բ��ø�������
     */
    timer_clk = clk_get_apb_rate();
    l_value = (timer_clk / 1000000) * (timer_info->time_ns / 1000);     // ��1000000000���Ϊ1000000��1000
    l_value = MIN(l_value, TIMER_COUNTER_MAX);
    h_value = (timer_clk / 1000000) * (timer_info->time_h_ns / 1000);     // ��1000000000���Ϊ1000000��1000
    h_value = MIN(h_value, l_value);

    // ���ƼĴ�����Ϣ
    ctrl = (lrc << LS1C_PWM_INT_LRC_EN)
           | (hrc << LS1C_PWM_INT_HRC_EN)
           | (0 << LS1C_PWM_CNTR_RST)
           | (0 << LS1C_PWM_INT_SR)
           | (1 << LS1C_PWM_INTEN)
           | (1 << LS1C_PWM_SINGLE)
           | (1 << LS1C_PWM_OE)
           | (1 << LS1C_PWM_CNT_EN);

    // ���ø����Ĵ���
    timer_reg_base = timer_get_reg_base(timer_info->timer);     // ��ȡ�Ĵ�������ַ
    reg_write_32(0,                     (volatile unsigned int *)(timer_reg_base + LS1C_PWM_HRC));
    reg_write_32(l_value--,                 (volatile unsigned int *)(timer_reg_base + LS1C_PWM_LRC));
    reg_write_32(h_value--,                 (volatile unsigned int *)(timer_reg_base + LS1C_PWM_HRC));
    reg_write_32(0,                     (volatile unsigned int *)(timer_reg_base + LS1C_PWM_CNTR));
    reg_write_32(ctrl,                  (volatile unsigned int *)(timer_reg_base + LS1C_PWM_CTRL));

    return ;
}