s5pv210 uboot-2012-10移植(四) 之使系统工作在1000Mhz
在uboot原来的代码里，有系统时钟的初始化函数，在board/samsung/smdkv210/lowlevel_init.S的system_clock_init函数，我大概看了一下，寄存器不一样，而且是汇编写的，所以我就改成用c语言来实现，在BL1阶段初始化一下，BL2阶段就不用重新初始化了。
1.arch/arm/lib/spl.c +43添加
//SystemClock #define APLL_LOCK (*(volatile unsigned int *)0xE0100000) #define MPLL_LOCK (*(volatile unsigned int *)0xE0100008) #define EPLL_LOCK (*(volatile unsigned int *)0xE0100010) #define VPLL_LOCK (*(volatile unsigned int *)0xE0100020) #define APLL_CON0 (*(volatile unsigned int *)0xE0100100) #define APLL_CON1 (*(volatile unsigned int *)0xE0100104) #define MPLL_CON (*(volatile unsigned int *)0xE0100108) #define EPLL_CON0 (*(volatile unsigned int *)0xE0100110) #define EPLL_CON1 (*(volatile unsigned int *)0xE0100114) #define VPLL_CON (*(volatile unsigned int *)0xE0100120) #define CLK_SRC0 (*(volatile unsigned int *)0xE0100200) #define CLK_DIV0 (*(volatile unsigned int *)0xE0100300) #define SETPLL(mdiv, pdiv, sdiv) ((1<<31)|(mdiv<<16)|(pdiv<<8)|(sdiv<<0)) #define APLL_MDIV 250 #define APLL_PDIV 6 #define APLL_SDIV 1 #define APLL_CON0_VAL SETPLL (APLL_MDIV, APLL_PDIV, APLL_SDIV) #define MPLL_MDIV 667 #define MPLL_PDIV 12 #define MPLL_SDIV 1 #define MPLL_CON_VAL SETPLL (MPLL_MDIV, MPLL_PDIV, MPLL_SDIV) #define PCLK_PSYS_RATIO 1 #define HCLK_PSYS_RATIO 4 #define PCLK_DSYS_RATIO 1 #define HCLK_DSYS_RATIO 3 #define PCLK_MSYS_RATIO 1 #define HCLK_MSYS_RATIO 4 #define A2M_RATIO 4 #define APLL_RATIO 0 #define CLK_DIV0_VAL ( (APLL_RATIO<<0)|\ (A2M_RATIO<<4)|\ (HCLK_MSYS_RATIO<<8)|\ (PCLK_MSYS_RATIO<<12)|\ (HCLK_DSYS_RATIO<<16)|\ (PCLK_DSYS_RATIO<<20)|\ (HCLK_PSYS_RATIO<<24)|\ (PCLK_PSYS_RATIO<<28) )
2. arch/arm/lib/spl.c +135添加
void init_SystemClock (void)
{
int i;
//CLK_DIV0 = 0;
APLL_CON0 = APLL_CON0_VAL;
MPLL_CON = MPLL_CON_VAL;
CLK_SRC0 = 0x1111;
CLK_DIV0 = CLK_DIV0_VAL;
//for (i=65535; i>=0; i--);
}
3. include/configs/smdkv210.h +178
/*#define CONFIG_SYS_PROMPT "SMDKC100 # "*/ #define CONFIG_SYS_PROMPT "SMDKV210 # "
4. include/configs/smdkv210.h +206
/*#define CONFIG_IDENT_STRING " for SMDKC100"*/ #define CONFIG_IDENT_STRING " for SMDKV210"
5. arch/arm/lib/spl.c +183
void __weak board_init_f(ulong dummy)
{
__attribute__((noreturn)) void (*uboot)(void);
#if 0
/* Set the stack pointer. */
asm volatile("mov sp, %0\n" : : "r"(CONFIG_SPL_STACK));
/* Clear the BSS. */
memset(__bss_start, 0, __bss_end__ - __bss_start);
/* Set global data pointer. */
gd = &gdata;
board_init_r(NULL, 0);
#endif
/*
// test
#define GPH0CON (*(volatile unsigned int *)0xE0200C00)
#define GPH0DAT (*(volatile unsigned int *)0xE0200C04)
GPH0CON = (1<<0) | (1<<4) | (1<<8) | (1<<12);
GPH0DAT = 10;
*/
init_SystemClock();
uart_init();
copy_uboot_to_ram();
//printf ("jump to u-boot image\r\n");
/* Jump to U-Boot image */
uboot = (void *)CONFIG_SYS_TEXT_BASE;
(*uboot)();
}
6. 好了，make一下，使用命令烧写spl/smdkv210-spl.bin和u-boot.bin到SD卡里，启动，就会看到下面这个画面了。
