imx6 怎么增加16c554 串口啊 在那个文件下？

杨帆！起航！

内核中 增加 8250选择项 但是没有映射的地址啊

Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled
8250___________INIT__266
8250___________probe
Unable to handle kernel NULL pointer dereference at virtual address 00000020
pgd = c0004000
[00000020] *pgd=00000000


求思路。。。。

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超級稻草人

了解下。。。

安臣

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杨帆！起航！

OK问题已解决。。。增加EIM片选。/* These registers settings are just valid for Numonyx M29W256GL7AN6E. */
static void mx6q_setup_weimcs(void)
{
        void __iomem *nor_reg = MX6_IO_ADDRESS(WEIM_BASE_ADDR);
        void __iomem *ccm_reg = MX6_IO_ADDRESS(CCM_BASE_ADDR);
        unsigned int reg;
        struct clk *clk;
        u32 rate;

        /* CLKCTL_CCGR6: Set emi_slow_clock to be on in all modes */
        reg = readl(ccm_reg + 0x80);
        reg |= 0x00000C00;
        writel(reg, ccm_reg + 0x80);

        /* Timing settings below based upon datasheet for M29W256GL7AN6E
           These setting assume that the EIM_SLOW_CLOCK is set to 132 MHz */
        clk = clk_get(NULL, "emi_slow_clk");
        if (IS_ERR(clk))
                printk(KERN_ERR "emi_slow_clk not found\n");

        rate = clk_get_rate(clk);
        if (rate != 132000000)
                printk(KERN_ERR "Warning: emi_slow_clk not set to 132 MHz!"
                       " WEIM NOR timing may be incorrect!\n");

        /*
         * For EIM General Configuration registers.
         *
         * CS0GCR1:
         *        GBC = 0; CSREC = 6; DSZ = 2; BL = 0;
         *        CREP = 1; CSEN = 1;
         *
         *        EIM Operation Mode: MUM = SRD = SWR = 0.
         *                (Async write/Async page read, none multiplexed)
         *
         * CS0GCR2:
         *        ADH = 1
         */
        writel(0x00620081, nor_reg);
        writel(0x00000001, nor_reg + 0x00000004);

        /*
         * For EIM Read Configuration registers.
         *
         * CS0RCR1:
         *        RWSC = 1C;
         *        RADVA = 0; RADVN = 2;
         *        OEA = 2; OEN = 0;
         *        RCSA = 0; RCSN = 0
         *
         * CS0RCR2:
         *        APR = 1 (Async Page Read);
         *        PAT = 4 (6 EIM clock sycles)
         */
        writel(0x1C022000, nor_reg + 0x00000008);
        writel(0x0000C000, nor_reg + 0x0000000C);

        /*
         * For EIM Write Configuration registers.
         *
         * CS0WCR1:
         *        WWSC = 20;
         *        WADVA = 0; WADVN = 1;
         *        WBEA = 1; WBEN = 2;
         *        WEA = 1; WEN = 6;
         *        WCSA = 1; WCSN = 2;
         *
         * CS0WCR2:
         *        WBCDD = 0
         */
        writel(0x1404a38e, nor_reg + 0x00000010);
        writel(0x00000000, nor_reg + 0x00000014);
}
6个寄存器的配置
3364      writel(0x00660081, nor_reg + 0x00000000); 片选0  128M 映射空间 数据线16-23 8位的
3365     writel(0x00000001, nor_reg + 0x00000004);
3366     writel(0x1c022000, nor_reg + 0x00000008);
3367     writel(0x0000C000, nor_reg + 0x0000000c);
3368     writel(0x1404a38e, nor_reg + 0x00000010);
3369     writel(0x00000000, nor_reg + 0x00000014);
3370     writel(0x00000001, nor_reg + 0x90);
3371     printk("GPR1__CSx____is____end%x\n",reg);

FSL_TICS_Rita

杨帆！起航！ 发表于 2015-12-24 15:48
OK问题已解决。。。增加EIM片选。/* These registers settings are just valid for Numonyx M29W256GL7AN6E ...

恭喜楼主问题已经解决，并热心分享解决方法。