Omap138开发板下以uboot2012.04.01为例分析uboot执行（六）

接上一篇文章：

6 )

#ifdef CONFIG_DAVINCI_MMC

       /*Set the GPIO direction as output */

       clrbits_le32((u32*)GPIO_BANK0_REG_DIR_ADDR, (0x01 << 11));

 

       /*Set the output as high */

       val= readl(GPIO_BANK0_REG_SET_ADDR);

       val|= (0x01 << 11);

       writel(val,GPIO_BANK0_REG_SET_ADDR);

#endif

7 )

/* GP0[7] is pwm blacklight for LCD to work on TL BOARD */

 

       /*Set the GPIO direction as output */

       clrbits_le32((u32*)GPIO_BANK0_REG_DIR_ADDR, (0x01 << 7));

 

       /*Set the output as low */

       val= readl(GPIO_BANK0_REG_SET_ADDR);

       val&= ~(0x01 << 7);

       writel(val,GPIO_BANK0_REG_SET_ADDR);

8）

davinci_emac_mii_mode_sel(HAS_RMII);

->

davinci_emac_mii_mode_sel(0)

->

选0表示为MII mode.

9 ) Power and Emulation Management

/* enable the console UART */

    writel((DAVINCI_UART_PWREMU_MGMT_FREE
| DAVINCI_UART_PWREMU_MGMT_URRST
|DAVINCI_UART_PWREMU_MGMT_UTRST),&davinci_uart2_ctrl_regs->pwremu_mgmt);;

->

#define DAVINCI_UART_PWREMU_MGMT_FREE     (1 << 0)

#define DAVINCI_UART_PWREMU_MGMT_URRST  (1 << 13)

#define DAVINCI_UART_PWREMU_MGMT_UTRST  (1 << 14)

13位置1，表示使能接收

14位置1，表示使能发射

0位置1，表示正常工作