另一种linux下的powerpc中断注册的方法

下面这种中断的配置方法比较畸形，不过和后面的配合起来，也是成功的。

static int ZwFPGA_irq_init(void)
{
      int ret;

      irq2 = irq_create_mapping(NULL,FPGA_IRQ2);
      printk(KERN_ERR"irq2=0x%08x\n",irq2);
      irq3 = irq_create_mapping(NULL,DSP_IRQ3);
      printk(KERN_ERR"irq3=0x%08x\n",irq3);
      mask_irq(irq3);
      mask_irq(irq2);
       
      /*    select irq2,set SICRH BIT 18 = 0    */
      *(volatile unsigned int *)(immr_base_addr + SICRH_ADDR) &= (~0x00002000);
      
      /*    set irq2 edge sensitive    */
      *(volatile unsigned int *)(immr_base_addr + SECNR_ADDR) |= (0x00002000);

      /*    Clear SEPNR bit    */
      *(volatile unsigned int *)(immr_base_addr + SEPNR_ADDR) |= (0x20000000);

      /*open the mask bit 2 to close the inttrupt*/
      *(volatile unsigned int *)(immr_base_addr + SEMSR_ADDR ) &= (~0x20000000);
      //*(volatile unsigned int *)(immr_base_addr + SEMSR_ADDR ) |= 0x20000000;

     
      ret = request_irq(irq2,fpga_irq_handler,SA_INTERRUPT,"fpga_driver",NULL);
      //perror(ret);
      if(ret < 0){
        printk(KERN_ERR"Request irq2 failed.\n");
        free_irq(irq2,NULL);
        return ret;
      }

       
      /*    select irq3,set SICRH BIT 19 = 0    */
      *(volatile unsigned int *)(immr_base_addr + SICRH_ADDR) &= (~0x00001000);
      
      /*    set irq3 edge sensitive    */
      *(volatile unsigned int *)(immr_base_addr + SECNR_ADDR) |= (0x00001000);

      /*    Clear SEPNR bit    */
      *(volatile unsigned int *)(immr_base_addr + SEPNR_ADDR) |= (0x10000000);

      /*open the mask bit 3 to close the inttrupt*/
      *(volatile unsigned int *)(immr_base_addr + SEMSR_ADDR ) &= (~0x10000000);
      //*(volatile unsigned int *)(immr_base_addr + SEMSR_ADDR ) |= (0x10000000);

    
      ret = request_irq(irq3,fpga_irq_handler,SA_INTERRUPT,"dpram_driver",NULL);
        //perror(ret);
      if(ret < 0){
        printk(KERN_ERR"Request irq3 failed.\n");
        free_irq(irq3,NULL);
        return ret;
      }
      
      disable_irq(irq3);
      disable_irq(irq2);
        
      unmask_irq(irq3);
      unmask_irq(irq2);

      return 0;
}

下面是对中断的打开函数
static int fpga_open(struct inode *inode, struct file *filp)
{
    /*close MASK bit of irq2 irq3*/
     *(volatile unsigned int *)(immr_base_addr + SEMSR_ADDR ) |= (0x30000000);

    printk(KERN_ERR"irq2=0x%08x\n",irq2);
    enable_irq(irq2);
    printk(KERN_ERR"irq3=0x%08x\n",irq3);
    enable_irq(irq3);

    return 0;
}

卸载函数如下：
static void irq_cleanup(void)
{
    mask_irq(irq3);
    mask_irq(irq2);
    free_irq(irq3,NULL);
    free_irq(irq2,NULL);
}

可以看到，这里面很多mask了，disable了，而平常中断基本上都不用的，所以，这些可用不可用，在这里面用了，就要用到底，要照应着。