sdhal.c

atmel de booloader 内有源代码 用blb编译

/****************************************Copyright (c)**************************************************
**                               Guangzhou ZHIYUAN electronics Co.,LTD.
**                                     
**                                 http://www.zyinside.com
**
**--------------File Info-------------------------------------------------------------------------------
** File Name: 				sdconfig.h
** Last modified Date: 		2006.01.09
** Last Version:			V1.0		
** Description: 			hardware abstract layer for s3c2410 SD/MMC
**
**------------------------------------------------------------------------------------------------------
** Created By: 				Ming Yuan Zheng 郑明远
** Created date: 			2006.01.09
** Version: 				V1.0
** Descriptions:			The original version 初始版本
**
**------------------------------------------------------------------------------------------------------
** Modified by:
** Modified date:
** Version:
** Description:
**
********************************************************************************************************/


#include "config.h"

/*********************************************************************************************************
** Function name: SD_HardWareInit
** Descriptions:  initialize the hardware condiction that access sd card
**                初始化访问SD卡的硬件条件	
** Input: 		  NULL	
** Output: 		  NULL
** Created by:    Ming Yuan Zheng 郑明远 
** Created Date:  2006-01-09 
**-------------------------------------------------------------------------------------------------------
** Modified by:
** Modified Date: 
**------------------------------------------------------------------------------------------------------
********************************************************************************************************/
void SD_HardWareInit(void)
{ 
	set_gpio_ctrl(GPIO_SDDAT3 | GPIO_MODE_SDDAT | GPIO_PULLUP_EN);  /* SDDAT3 is GPIO and pulled up */
	set_gpio_ctrl(GPIO_SDDAT2 | GPIO_MODE_SDDAT | GPIO_PULLUP_EN);  /* SDDAT2 is GPIO and pulled up */
	set_gpio_ctrl(GPIO_SDDAT1 | GPIO_MODE_SDDAT | GPIO_PULLUP_EN);  /* SDDAT1 is GPIO and pulled up */
	set_gpio_ctrl(GPIO_SDDAT0 | GPIO_MODE_SDDAT | GPIO_PULLUP_EN);	/* SDDAT0 is GPIO and pulled up */ 
	set_gpio_ctrl(GPIO_SDCMD | GPIO_MODE_SDCMD | GPIO_PULLUP_EN);   /* SDCMD is GPIO and pulled up */
	set_gpio_ctrl(GPIO_SDCLK | GPIO_MODE_SDCLK | GPIO_PULLUP_EN);   /* SDCLK is GPIO and pulled up */	
	
	SD_Powerup();					/* supply power to sd/mmc card */
	SD_Clk400k();					/* set the clock(read and write sd/mmc) to 40KHz */
}


/*********************************************************************************************************
** Function name: SD_Powerup
** Descriptions:  supply power to sd/mmc card
**                给 sd/mmc 卡上电
** Input: 		  NULL	
** Output: 		  NULL
** Created by:    Ming Yuan Zheng 郑明远  
** Created Date:  2006-01-09
**-------------------------------------------------------------------------------------------------------
** Modified by:
** Modified Date: 
**------------------------------------------------------------------------------------------------------
********************************************************************************************************/
void SD_Powerup(void)
{
	/* Set block size to 512 bytes  设置块大小为512字节 */
	SDIBSIZE = SD_BLOCKSIZE;

	/* Set timeout count 设置超时计数器 */
	SDIDTIMER = 0xffff;

	/* Disable SDI interrupt 关闭SDI中断 */
	SDIIMSK = 0x0;

	/* Type B, FIFO reset, SD clock enable 数据传输类型为B, FIFO复位, 时钟使能 */
	SDICON = SDICON_LE | SDICON_FRESET | SDICON_ENCLK;

	/* clear all bits of SDIDSTA register 清除SDI数据状态寄存器所有的位 */
	SDIDSTA = SDIDSTA_ALL;

	/* delay */
	mdelay(125);
}


/*********************************************************************************************************
** Function name: set_clock
** Descriptions:  set the clock for read and write sd/mmc card
**                设置读写SD卡的频率值
** Input: 		  int rate: frequency value   频率值	
** Output: 		  NULL
** Created by:    Ming Yuan Zheng 郑明远  
** Created Date:  2006-01-09
**-------------------------------------------------------------------------------------------------------
** Modified by:
** Modified Date: 
**------------------------------------------------------------------------------------------------------
********************************************************************************************************/
static void set_clock(int rate)
{
	unsigned long val, pclk;

	if (rate >= MMC_MMC_CLOCK_HIGH) 
		rate = MMC_MMC_CLOCK_HIGH;					 /* 最大时钟为20MHz */
	
    /* read s3c2410 PCLK */ 
 	pclk = s3c2410_get_bus_clk(GET_PCLK);			 /* 读取PCLK时钟 */	
	
	/* calculate the clock that operate sd/mmc*/
	val = (pclk / 2 / (rate));						 /* 计算操作sd/mmc卡的时钟 */
	
	/* write the value to prescaler register */  
	SDIPRE = (SDIPRE_MSK & val); 					 /* 将频率值写入分频寄存器 */
}


/*********************************************************************************************************
** Function name: SD_Clk400k
** Descriptions:  set the clock(read or write sd/mmc) to 400KHz
**                设置访问sd/mmc的速度为400KHz
** Input: 		  NULL	
** Output: 		  NULL
** Created by:    Ming Yuan Zheng 郑明远  
** Created Date:  2006-01-09
**-------------------------------------------------------------------------------------------------------
** Modified by:
** Modified Date: 
**------------------------------------------------------------------------------------------------------
********************************************************************************************************/
void SD_Clk400k(void)
{
	set_clock(400000);								/* 400K Hz */
}


/*********************************************************************************************************
** Function name: SD_ClkToMax
** Descriptions:  set the clock(read or write sd/mmc) to max
**                设置访问sd/mmc的速度到最高
** Input: 		  NULL	
** Output: 		  NULL
** Created by:    Ming Yuan Zheng 郑明远  
** Created Date:  2006-01-09
**-------------------------------------------------------------------------------------------------------
** Modified by:
** Modified Date: 
**------------------------------------------------------------------------------------------------------
********************************************************************************************************/
void SD_ClkToMax(void)
{
	set_clock(MMC_MMC_CLOCK_HIGH);			  		/* Max frequency */
}