OK335xS U-boot GPIO control hacking

/****************************************************************************************
 *                           OK335xS U-boot GPIO control hacking
 * 声明:
 *     本文主要是跟踪U-boot中如何设置GPIO口电平。
 *
 *                                                  2015-9-26 晴 深圳 南山平山村 曾剑锋
 ***************************************************************************************/

cat board/forlinx/ok335x/evm.c                                                                      
int board_init(void)                                                                                
{                                                                                                   
    int c = 100;                                                                                    
    /* Configure the i2c0 pin mux */                                                                
    enable_i2c0_pin_mux();                                                                          
                                                                                                    
    i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);                                           
                                                                                                    
    board_id = GP_BOARD;                                                                            
    profile = 1;    /* profile 0 is internally considered as 1 */                                   
    daughter_board_connected = 1;                                                                   
                                                                                                    
    configure_evm_pin_mux(board_id, header.version, profile, daughter_board_connected); --+         
                                                                                          |         
    /**                                                                                   |         
      * 1. 参考资料:                                                                     |
      *   AM335x ARM Cortex-A8 Microprocessors (MPUs) Technical Reference Manual (Rev. H) |
      *                                                                                   |
      * 2. ARM Cortex-A8 Memory Map                                                       |
      *             Table 2-2. L4_WKUP Peripheral Memory Map (continued)                  |
      * +-------------+---------------------+-------------------+------+----------------+ |         
      * | Region Name | Start Address (hex) | End Address (hex) | Size | Description    | |         
      * +-------------+---------------------+-------------------+------+----------------+ |         
      * | GPIO0       | 0x44E0_7000         | 0x44E0_7FFF       | 4KB  | GPIO Registers | |         
      * +-------------+---------------------+-------------------+------+----------------+ |         
      *                                                                                   |         
      * 3. GPIO Registers(4068 页)                                                      |
      *                 Table 25-5. GPIO REGISTERS                                        |
      * +--------+-------------------+---------------+-------------------+                |         
      * | Offset | Acronym           | Register Name | Section           |                |         
      * +--------+-------------------+---------------+-------------------+                |         
      * | 134h   | GPIO_OE           |               | Section 25.4.1.16 |<-+             |         
      * +--------+-------------------+---------------+-------------------+  |             |         
      * | 190h   | GPIO_CLEARDATAOUT |               | Section 25.4.1.25 |  |<-+          |         
      * +--------+-------------------+---------------+-------------------+  |  |          |         
      * | 194h   | GPIO_SETDATAOUT   |               | Section 25.4.1.26 |  |  |<-+       |         
      * +--------+-------------------+---------------+-------------------+  |  |  |       |         
      */                                                                    |  |  |       |         
    /* set gpio0_7 gpio0_12 gpio0_22 gpio0_23 output mode */                |  |  |       |         
    __raw_writel(~((1<<7) | (1<<12) | (1<<22) |(1<<23)), 0x44E07134);-------+  |  |       |         
    /* set gpio0_7 12 19 23 low */                                             |  |       |         
    __raw_writel((1<<7) | (1<<19) | (1<<23), 0x44E07190);            ----------+  |       |         
    /* set gpio0_22 high to height */                                             |       |         
    __raw_writel( (1<<12) | (1<<22), 0x44E07194);                    -------------+       |         
                                                                                          |         
                                                                                          |         
#ifndef CONFIG_SPL_BUILD                                                                  |         
    board_evm_init();                                                                     |         
#endif                                                                                    |         
    gpmc_init();                                                                          |         
                                                                                          |         
    return 0;                                                                             |         
}               +-------------------------------------------------------------------------+         
                V                                                                                   
void configure_evm_pin_mux(unsigned char dghtr_brd_id, char version[4], unsigned short              
        profile, unsigned int daughter_board_flag)                                                  
{                                                                                                   
    if (dghtr_brd_id > BASE_BOARD)                                                                  
        return;                                                                                     
                                                                                                    
    set_evm_pin_mux(am335x_evm_pin_mux[0], profile,daughter_board_flag);                            
}                                 |                                                                 
                                  V                                                                 
static struct evm_pin_mux *am335x_evm_pin_mux[] = {                                                 
    general_purpose_evm_pin_mux,                      ----------------------+                       
};                                                                          |                       
                                                                            |                       
/*                                                                          |                       
 * Update the structure with the modules present in the general purpose     |                       
 * board and the profiles in which the modules are present.                 |                       
 * If the module is physically present but if it is not available           |                       
 * in any of the profile, then do not update it.                            |                       
 * For eg, nand is avialable only in the profiles 0 and 1, whereas          |                       
 * UART0  is available in all the profiles.                                 |                       
 */                                                                         |                       
static struct evm_pin_mux general_purpose_evm_pin_mux[] = {      <----------+                       
    {i2c1_pin_mux, PROFILE_ALL & ~PROFILE_2 & ~PROFILE_4, DEV_ON_BASEBOARD},                        
                                                                                                    
#ifdef CONFIG_NAND                                                                                  
    {nand_pin_mux, PROFILE_ALL & ~PROFILE_2 & ~PROFILE_3, DEV_ON_DGHTR_BRD},                        
#endif                                                                                              
                                                                                                    
#ifndef CONFIG_NO_ETH                                                                               
    {mii1_pin_mux, PROFILE_ALL, DEV_ON_BASEBOARD},                                                  
#endif                                                                                              
                                                                                                    
#ifdef CONFIG_MMC                                                                                   
    {mmc0_pin_mux, PROFILE_ALL, DEV_ON_BASEBOARD},                                                  
#endif                                                                                              
    {backlight_pin_mux, PROFILE_ALL, DEV_ON_BASEBOARD},           -----+                            
    {maxttl_model_pin_mux, PROFILE_ALL, DEV_ON_BASEBOARD},             |                            
    {lcd_pin_mux, PROFILE_ALL, DEV_ON_BASEBOARD},                      |                            
    {uart0_pin_mux, PROFILE_ALL, DEV_ON_BASEBOARD},                    |                            
    {0},                                                               |                            
};                                                                     |                            
                                                                       |                            
static struct module_pin_mux backlight_pin_mux[] = {              <----+                            
    {OFFSET(ecap0_in_pwm0_out), MODE(7) | PULLUP_EN | RXACTIVE}, /* GPIO0_7 */                      
    {OFFSET(uart1_ctsn), MODE(7) | PULLUDDIS | RXACTIVE},        /* GPIO0_ 12 */                    
    {-1},                                                                                           
};                                                                                                  

 

posted on 2015-09-26 15:38  zengjf  阅读(615)  评论(0编辑  收藏  举报

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