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| 麻烦朋友解释下LINUX的虚拟地址到物理地址的映射问题,我正在看一个蜂鸣器的驱动, 看到下面这个函数
 static void PWM_Set_Freq( unsigned long freq )
 {
 unsigned long tcon;
 unsigned long tcnt;
 unsigned long tcfg1;
 unsigned long tcfg0;
 
 struct clk *clk_p;
 unsigned long pclk;
 
 / / GPB0 as tout0, pwm output
 s3c2410_gpio_cfgpin(S3C2410_GPB0, S3C2410_GPB0_TOUT0);
 
 printk (KERN_INFO "\tS3C2410_TCON =0x%x\n",S3C2410_TCON);
 tcon = __raw_readl(S3C2410_TCON);
 tcfg1 = __raw_readl(S3C2410_TCFG1);
 tcfg0 = __raw_readl(S3C2410_TCFG0);
 
 //prescaler = 50
 tcfg0 &= ~S3C2410_TCFG_PRESCALER0_MASK;
 tcfg0 |= (50 - 1);
 
 //mux = 1/16
 tcfg1 &= ~S3C2410_TCFG1_MUX0_MASK;
 tcfg1 |= S3C2410_TCFG1_MUX0_DIV16;
 
 __raw_writel(tcfg1, S3C2410_TCFG1);
 __raw_writel(tcfg0, S3C2410_TCFG0);
 
 clk_p = clk_get(NULL, "pclk");
 pclk  = clk_get_rate(clk_p);
 tcnt  = (pclk/50/16)/freq;
 
 __raw_writel(tcnt, S3C2410_TCNTB(0));
 __raw_writel(tcnt/2, S3C2410_TCMPB(0));
 
 tcon &= ~0x1f;
 tcon |= 0xb;                //disable deadzone, auto-reload, inv-off, update TCNTB0&TCMPB0, start timer 0
 __raw_writel(tcon, S3C2410_TCON);
 
 tcon &= ~2;                        //clear manual update bit
 __raw_writel(tcon, S3C2410_TCON);
 }
 
 其中的
 tcon = __raw_readl(S3C2410_TCON);
 tcfg1 = __raw_readl(S3C2410_TCFG1);
 tcfg0 = __raw_readl(S3C2410_TCFG0);
 
 用到的虚拟地址S3C2410_TCON,S3C2410_TCFG0,S3C2410_TCFG1是怎么映射到实际的物理地址的,拜托知道的朋友解说解说,先谢谢了
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