Xenomai屏蔽PWM TIMER0-3的修改

static inline void set_dec(unsigned long reload)
{
    __raw_writel(reload, S3C2410_TCNTB(4));
    unsigned long tcon=__raw_readl(S3C2410_TCON)&0xffff;
    tcon|=free_running_tcon&0xff0000;
    /* Manual update */
    __raw_writel(tcon | S3C2410_TCON_T4MANUALUPD, S3C2410_TCON);
    /* Start timer */
    __raw_writel(tcon | S3C2410_TCON_T4START, S3C2410_TCON);
}