我用飞凌2440板子，写spi驱动，但spi时钟始终没有信号，只输出个高电平

处理器是s3c2440的，看了datasheet，寄存器都设置好了，试了很多办法，却始终没有时钟信号，很郁闷
初始化程序如下：
*CLKCON|=0x40000;
printk("CLKCON=0x%x\n",*CLKCON);

*SPPRE1=23;
printk("SPPRE1=0x%x\n",*SPPRE1);

*GPGCON|=0x0000fcc0;
printk("GPGCON=0x%x\n",*GPGCON);

*GPGUP&=0xff17;
printk("GPGUP=0x%x\n",*GPGUP);

printk("Initiate SPPIN1=0x%x\n",*SPPIN1);

*SPCON1=0x18;
printk("SPCON1=0x%x\n",*SPCON1);

for(i=0;i<10;i++)
{
*SPTDAT1=0xff;
}

if(*SPSTA1&0x01)
{
printk("Data TR ready!\n");
}
else
*SPSTA1|=0x01;
printk("SPSTA1=0x%x\n",*SPSTA1);


if(!(*SPSTA1&0x01))
{
*SPSTA1|=0x01;
}
*SPTDAT1=0xff;