移植uboot到2440
一、修改顶层Makefile，加入：
shanl2440_config : unconfig @$(MKCONFIG) $(@:_config=) arm arm920t shanl2440 NULL s3c24x0arm: CPU 的架构(ARCH)
arm920t: CPU 的类型(CPU),其对应于 cpu/arm920t 子目录。
shanl2440: 开发板的型号(BOARD),对应于 board/shanl2440 目录。
NULL: 开发者/或经销商(vender)。(此处没加 vender,为 NULL。) ，如果有vendor,则开发板的目录就在board/vendor/shanl下
s3c24x0: 片上系统(SOC)。
二、建立自己开发板的board信息：
在board下面建立shanl2440目录，并把smdk2410目录中的内容复制过来：
shanl@shanl-Aspire-4740:~/Kernel/u-boot-1.1.6/board$ mkdir shanl2440 shanl@shanl-Aspire-4740:~/Kernel/u-boot-1.1.6/board$ cp smdk2410/* shanl2440/
三、编译：
发现出现一下错误：
/home/shanl/Kernel/u-boot-1.1.6/include/config.h:2: fatal error: configs/shanl2440.h: 没有那个文件或目录解决办法：
进入相应的目录，将2410的配置复制一份shanl2440.h
shanl@shanl-Aspire-4740:~/Kernel/u-boot-1.1.6$ cd include/configs/ shanl@shanl-Aspire-4740:~/Kernel/u-boot-1.1.6/include/configs$ cp smdk2410.h shanl2440.h重新make一下，问题解决，会在根目录下面生成u-boot.bin.
这个u-boot.bin只是披了一层2440外衣的2410可执行程序。下面需要对代码做相关的修改从而支持2440
四、加入板子的配置：
在include\configs\Shanl2440.h中加入：
#define CONFIG_SHANL2440 1 /* in a SAMSUNG S3C2440 SoC */五、关闭看门狗和中断：
将：
/* turn off the watchdog */ #if defined(CONFIG_S3C2400) # define pWTCON 0x15300000 # define INTMSK 0x14400008 /* Interupt-Controller base addresses */ # define CLKDIVN 0x14800014 /* clock divisor register */ #elif defined(CONFIG_S3C2410) # define pWTCON 0x53000000 # define INTMSK 0x4A000008 /* Interupt-Controller base addresses */ # define INTSUBMSK 0x4A00001C # define CLKDIVN 0x4C000014 /* clock divisor register */ #endif #if defined(CONFIG_S3C2400) || defined(CONFIG_S3C2410) ldr r0, =pWTCON mov r1, #0x0 str r1, [r0] /* * mask all IRQs by setting all bits in the INTMR - default */ mov r1, #0xffffffff ldr r0, =INTMSK str r1, [r0] # if defined(CONFIG_S3C2410) ldr r1, =0x3ff ldr r0, =INTSUBMSK str r1, [r0] # endif修改为：
/* turn off the watchdog */ #if defined(CONFIG_S3C2400) # define pWTCON 0x15300000 # define INTMSK 0x14400008 /* Interupt-Controller base addresses */ # define CLKDIVN 0x14800014 /* clock divisor register */ #elif defined(CONFIG_S3C2410) || defined(CONFIG_SHANL2440) # define pWTCON 0x53000000 # define INTMSK 0x4A000008 /* Interupt-Controller base addresses */ # define INTSUBMSK 0x4A00001C # define CLKDIVN 0x4C000014 /* clock divisor register */ #endif #if defined(CONFIG_S3C2400) || defined(CONFIG_S3C2410) || defined(CONFIG_SHANL2440) ldr r0, =pWTCON mov r1, #0x0 str r1, [r0] /* * mask all IRQs by setting all bits in the INTMR - default */ mov r1, #0xffffffff ldr r0, =INTMSK str r1, [r0] # if defined(CONFIG_S3C2410) || defined(CONFIG_SHANL2440) ldr r1, =0x3ff ldr r0, =INTSUBMSK str r1, [r0] # endif
六、MMU和SDRAM的设置：
将：
/* * we do sys-critical inits only at reboot, * not when booting from ram! */ #ifndef CONFIG_SKIP_LOWLEVEL_INIT bl cpu_init_crit #endif改为:
/* * we do sys-critical inits only at reboot, * not when booting from ram! */ #ifndef CONFIG_SKIP_LOWLEVEL_INIT adr r0, _start /* r0 <- current position of code */ ldr r1, _TEXT_BASE /* test if we run from flash or RAM */ cmp r0, r1 /* don't reloc during debug */ blne cpu_init_crit #endif对当前所在地址做一下判断，是运行到sdram上还是nand上，如果已经在sdram上了，就跳过mmu和sdram的设置
七、设置时钟：
首先设置栈，将栈的设置代码放到mmu和sdram设置的后面：
代码如下：
blne cpu_init_crit #endif /* Set up the stack */ stack_setup: ldr r0, _TEXT_BASE /* upper 128 KiB: relocated uboot */ sub r0, r0, #CFG_MALLOC_LEN /* malloc area */ sub r0, r0, #CFG_GBL_DATA_SIZE /* bdinfo */ #ifdef CONFIG_USE_IRQ sub r0, r0, #(CONFIG_STACKSIZE_IRQ+CONFIG_STACKSIZE_FIQ) #endif sub sp, r0, #12 /* leave 3 words for abort-stack */然后跳用c函数对时钟进行设置：
#ifndef CONFIG_SKIP_LOWLEVEL_INIT
bl clock_init
#endif
在 board\shanl2440下面建立文件Boot_init.c
加入时钟的初始化代码：
static inline void delay (unsigned long loops)
{
__asm__ volatile ("1:\n"
"subs %0, %1, #1\n"
"bne 1b":"=r" (loops):"0" (loops));
}
/* S3C2440: Mpll = (2*m * Fin) / (p * 2^s), UPLL = (m * Fin) / (p * 2^s)
* m = M (the value for divider M)+ 8, p = P (the value for divider P) + 2
*/
#define S3C2440_MPLL_400MHZ ((0x5c<<12)|(0x01<<4)|(0x01))
#define S3C2440_UPLL_48MHZ ((0x38<<12)|(0x02<<4)|(0x02))
#define S3C2440_CLKDIV (0x05) // | (1<<3)) /* FCLK:HCLK:PCLK = 1:4:8, UCLK = UPLL/2 */
void clock_init(void)
{
S3C24X0_CLOCK_POWER *clk_power = (S3C24X0_CLOCK_POWER *)0x4C000000;
/* FCLK:HCLK:PCLK = 1:4:8 */
clk_power->CLKDIVN = S3C2440_CLKDIV;
/* change to asynchronous bus mod */
__asm__( "mrc p15, 0, r1, c1, c0, 0\n" /* read ctrl register */
"orr r1, r1, #0xc0000000\n" /* Asynchronous */
"mcr p15, 0, r1, c1, c0, 0\n" /* write ctrl register */
:::"r1"
);
/* to reduce PLL lock time, adjust the LOCKTIME register */
clk_power->LOCKTIME = 0xFFFFFFFF;
/* configure UPLL */
clk_power->UPLLCON = S3C2440_UPLL_48MHZ;
/* some delay between MPLL and UPLL */
delay (4000);
/* configure MPLL */
clk_power->MPLLCON = S3C2440_MPLL_400MHZ;
/* some delay between MPLL and UPLL */
delay (8000);
}修改board\shanl2440下的Makefile：
COBJS := shanl2440.o flash.o board_init.o SOBJS := lowlevel_init.o
时钟设置好了，还要修改一个文件speed.c,这个文件供uboot第2阶段使用，修改后的文件如下（以后再分析）：
#include <common.h>
#if defined(CONFIG_S3C2400) || defined (CONFIG_S3C2410) || defined (CONFIG_TRAB)
#if defined(CONFIG_S3C2400)
#include <s3c2400.h>
#elif defined(CONFIG_S3C2410) || defined (CONFIG_SHANL2440)
#include <s3c2410.h>
#endif
DECLARE_GLOBAL_DATA_PTR;
#define MPLL 0
#define UPLL 1
/* ------------------------------------------------------------------------- */
/* NOTE: This describes the proper use of this file.
*
* CONFIG_SYS_CLK_FREQ should be defined as the input frequency of the PLL.
*
* get_FCLK(), get_HCLK(), get_PCLK() and get_UCLK() return the clock of
* the specified bus in HZ.
*/
/* ------------------------------------------------------------------------- */
static ulong get_PLLCLK(int pllreg)
{
S3C24X0_CLOCK_POWER * const clk_power = S3C24X0_GetBase_CLOCK_POWER();
ulong r, m, p, s;
if (pllreg == MPLL)
r = clk_power->MPLLCON;
else if (pllreg == UPLL)
r = clk_power->UPLLCON;
else
hang();
m = ((r & 0xFF000) >> 12) + 8;
p = ((r & 0x003F0) >> 4) + 2;
s = r & 0x3;
/* support both of S3C2410 and S3C2440, by www.100ask.net */
return((CONFIG_SYS_CLK_FREQ * m * 2) / (p << s)); /* S3C2440 */
}
/* return FCLK frequency */
ulong get_FCLK(void)
{
return(get_PLLCLK(MPLL));
}
/* for s3c2440 */
#define S3C2440_CLKDIVN_PDIVN (1<<0)
#define S3C2440_CLKDIVN_HDIVN_MASK (3<<1)
#define S3C2440_CLKDIVN_HDIVN_1 (0<<1)
#define S3C2440_CLKDIVN_HDIVN_2 (1<<1)
#define S3C2440_CLKDIVN_HDIVN_4_8 (2<<1)
#define S3C2440_CLKDIVN_HDIVN_3_6 (3<<1)
#define S3C2440_CLKDIVN_UCLK (1<<3)
#define S3C2440_CAMDIVN_CAMCLK_MASK (0xf<<0)
#define S3C2440_CAMDIVN_CAMCLK_SEL (1<<4)
#define S3C2440_CAMDIVN_HCLK3_HALF (1<<8)
#define S3C2440_CAMDIVN_HCLK4_HALF (1<<9)
#define S3C2440_CAMDIVN_DVSEN (1<<12)
/* return HCLK frequency */
ulong get_HCLK(void)
{
S3C24X0_CLOCK_POWER * const clk_power = S3C24X0_GetBase_CLOCK_POWER();
unsigned long clkdiv;
unsigned long camdiv;
int hdiv = 1;
clkdiv = clk_power->CLKDIVN;
camdiv = clk_power->CAMDIVN;
/* work out clock scalings */
switch (clkdiv & S3C2440_CLKDIVN_HDIVN_MASK) {
case S3C2440_CLKDIVN_HDIVN_1:
hdiv = 1;
break;
case S3C2440_CLKDIVN_HDIVN_2:
hdiv = 2;
break;
case S3C2440_CLKDIVN_HDIVN_4_8:
hdiv = (camdiv & S3C2440_CAMDIVN_HCLK4_HALF) ? 8 : 4;
break;
case S3C2440_CLKDIVN_HDIVN_3_6:
hdiv = (camdiv & S3C2440_CAMDIVN_HCLK3_HALF) ? 6 : 3;
break;
return get_FCLK() / hdiv;
}
}
/* return PCLK frequency */
ulong get_PCLK(void)
{
S3C24X0_CLOCK_POWER * const clk_power = S3C24X0_GetBase_CLOCK_POWER();
unsigned long clkdiv;
unsigned long camdiv;
int hdiv = 1;
clkdiv = clk_power->CLKDIVN;
camdiv = clk_power->CAMDIVN;
/* work out clock scalings */
switch (clkdiv & S3C2440_CLKDIVN_HDIVN_MASK) {
case S3C2440_CLKDIVN_HDIVN_1:
hdiv = 1;
break;
case S3C2440_CLKDIVN_HDIVN_2:
hdiv = 2;
break;
case S3C2440_CLKDIVN_HDIVN_4_8:
hdiv = (camdiv & S3C2440_CAMDIVN_HCLK4_HALF) ? 8 : 4;
break;
case S3C2440_CLKDIVN_HDIVN_3_6:
hdiv = (camdiv & S3C2440_CAMDIVN_HCLK3_HALF) ? 6 : 3;
break;
}
return get_FCLK() / hdiv / ((clkdiv & S3C2440_CLKDIVN_PDIVN)? 2:1);
}
/* return UCLK frequency */
ulong get_UCLK(void)
{
return(get_PLLCLK(UPLL));
}
#endif /* defined(CONFIG_S3C2400) || defined (CONFIG_S3C2410) || defined (CONFIG_TRAB) */
八、重定位代码：
将
#ifndef CONFIG_SKIP_RELOCATE_UBOOT
relocate: /* relocate U-Boot to RAM */
adr r0, _start /* r0 <- current position of code */
ldr r1, _TEXT_BASE /* test if we run from flash or RAM */
cmp r0, r1 /* don't reloc during debug */
beq stack_setup
ldr r2, _armboot_start
ldr r3, _bss_start
sub r2, r3, r2 /* r2 <- size of armboot */
add r2, r0, r2 /* r2 <- source end address */
copy_loop:
ldmia r0!, {r3-r10} /* copy from source address [r0] */
stmia r1!, {r3-r10} /* copy to target address [r1] */
cmp r0, r2 /* until source end addreee [r2] */
ble copy_loop
#endif /* CONFIG_SKIP_RELOCATE_UBOOT */
修改为：
#ifndef CONFIG_SKIP_RELOCATE_UBOOT
relocate: /* relocate U-Boot to RAM */
adr r0, _start /* r0 <- current position of code */
ldr r1, _TEXT_BASE /* test if we run from flash or RAM */
cmp r0, r1 /* don't reloc during debug */
beq clear_bss
ldr r2, _armboot_start
ldr r3, _bss_start
sub r2, r3, r2 /* r2 <- size of armboot */
#if 1
bl CopyCode2Ram /* r0: source, r1: dest, r2: size */
#else
add r2, r0, r2 /* r2 <- source end address */
copy_loop:
ldmia r0!, {r3-r10} /* copy from source address [r0] */
stmia r1!, {r3-r10} /* copy to target address [r1] */
cmp r0, r2 /* until source end addreee [r2] */
ble copy_loop
#endif
#endif /* CONFIG_SKIP_RELOCATE_UBOOT */对于CopyCode2Ram的实现可以在boot_init.c中添加，主要是nandflash的读操作：
#define BUSY 1
#define NAND_SECTOR_SIZE 512
#define NAND_BLOCK_MASK (NAND_SECTOR_SIZE - 1)
#define NAND_SECTOR_SIZE_LP 2048
#define NAND_BLOCK_MASK_LP (NAND_SECTOR_SIZE_LP - 1)
/* 供外部调用的函数 */
void nand_init_ll(void);
void nand_read_ll(unsigned char *buf, unsigned long start_addr, int size);
/* NAND Flash操作的总入口, 它们将调用S3C2410或S3C2440的相应函数 */
static void nand_reset(void);
static void wait_idle(void);
static void nand_select_chip(void);
static void nand_deselect_chip(void);
static void write_cmd(int cmd);
static void write_addr(unsigned int addr);
static unsigned char read_data(void);
/* S3C2440的NAND Flash处理函数 */
static void s3c2440_nand_reset(void);
static void s3c2440_wait_idle(void);
static void s3c2440_nand_select_chip(void);
static void s3c2440_nand_deselect_chip(void);
static void s3c2440_write_cmd(int cmd);
static void s3c2440_write_addr(unsigned int addr);
static unsigned char s3c2440_read_data(void);
/* S3C2440的NAND Flash操作函数 */
/* 复位 */
static void s3c2440_nand_reset(void)
{
s3c2440_nand_select_chip();
s3c2440_write_cmd(0xff); // 复位命令
s3c2440_wait_idle();
s3c2440_nand_deselect_chip();
}
/* 等待NAND Flash就绪 */
static void s3c2440_wait_idle(void)
{
int i;
S3C2440_NAND * s3c2440nand = (S3C2440_NAND *)0x4e000000;
volatile unsigned char *p = (volatile unsigned char *)&s3c2440nand->NFSTAT;
while(!(*p & BUSY))
for(i=0; i<10; i++);
}
/* 发出片选信号 */
static void s3c2440_nand_select_chip(void)
{
int i;
S3C2440_NAND * s3c2440nand = (S3C2440_NAND *)0x4e000000;
s3c2440nand->NFCONT &= ~(1<<1);
for(i=0; i<10; i++);
}
/* 取消片选信号 */
static void s3c2440_nand_deselect_chip(void)
{
S3C2440_NAND * s3c2440nand = (S3C2440_NAND *)0x4e000000;
s3c2440nand->NFCONT |= (1<<1);
}
/* 发出命令 */
static void s3c2440_write_cmd(int cmd)
{
S3C2440_NAND * s3c2440nand = (S3C2440_NAND *)0x4e000000;
volatile unsigned char *p = (volatile unsigned char *)&s3c2440nand->NFCMD;
*p = cmd;
}
/* 发出地址 */
static void s3c2440_write_addr(unsigned int addr)
{
int i;
S3C2440_NAND * s3c2440nand = (S3C2440_NAND *)0x4e000000;
volatile unsigned char *p = (volatile unsigned char *)&s3c2440nand->NFADDR;
*p = addr & 0xff;
for(i=0; i<10; i++);
*p = (addr >> 9) & 0xff;
for(i=0; i<10; i++);
*p = (addr >> 17) & 0xff;
for(i=0; i<10; i++);
*p = (addr >> 25) & 0xff;
for(i=0; i<10; i++);
}
/* 发出地址 */
static void s3c2440_write_addr_lp(unsigned int addr)
{
int i;
S3C2440_NAND * s3c2440nand = (S3C2440_NAND *)0x4e000000;
volatile unsigned char *p = (volatile unsigned char *)&s3c2440nand->NFADDR;
int col, page;
col = addr & NAND_BLOCK_MASK_LP;
page = addr / NAND_SECTOR_SIZE_LP;
*p = col & 0xff; /* Column Address A0~A7 */
for(i=0; i<10; i++);
*p = (col >> 8) & 0x0f; /* Column Address A8~A11 */
for(i=0; i<10; i++);
*p = page & 0xff; /* Row Address A12~A19 */
for(i=0; i<10; i++);
*p = (page >> 8) & 0xff; /* Row Address A20~A27 */
for(i=0; i<10; i++);
*p = (page >> 16) & 0x03; /* Row Address A28~A29 */
for(i=0; i<10; i++);
}
/* 读取数据 */
static unsigned char s3c2440_read_data(void)
{
S3C2440_NAND * s3c2440nand = (S3C2440_NAND *)0x4e000000;
volatile unsigned char *p = (volatile unsigned char *)&s3c2440nand->NFDATA;
return *p;
}
/* 在第一次使用NAND Flash前，复位一下NAND Flash */
static void nand_reset(void)
{
s3c2440_nand_reset();
}
static void wait_idle(void)
{
s3c2440_wait_idle();
}
static void nand_select_chip(void)
{
int i;
s3c2440_nand_select_chip();
for(i=0; i<10; i++);
}
static void nand_deselect_chip(void)
{
s3c2440_nand_deselect_chip();
}
static void write_cmd(int cmd)
{
s3c2440_write_cmd(cmd);
}
static void write_addr(unsigned int addr)
{
s3c2440_write_addr(addr);
}
static void write_addr_lp(unsigned int addr)
{
s3c2440_write_addr_lp(addr);
}
static unsigned char read_data(void)
{
return s3c2440_read_data();
}
/* 初始化NAND Flash */
void nand_init_ll(void)
{
S3C2440_NAND * s3c2440nand = (S3C2440_NAND *)0x4e000000;
#define TACLS 0
#define TWRPH0 2
#define TWRPH1 0
/* 设置时序 */
s3c2440nand->NFCONF = (TACLS<<12)|(TWRPH0<<8)|(TWRPH1<<4);
/* 使能NAND Flash控制器, 初始化ECC, 禁止片选 */
s3c2440nand->NFCONT = (1<<4)|(1<<1)|(1<<0);
/* 复位NAND Flash */
nand_reset();
}
/* 读函数 */
void nand_read_ll(unsigned char *buf, unsigned long start_addr, int size)
{
int i, j;
if ((start_addr & NAND_BLOCK_MASK) || (size & NAND_BLOCK_MASK)) {
return ; /* 地址或长度不对齐 */
}
/* 选中芯片 */
nand_select_chip();
for(i=start_addr; i < (start_addr + size);) {
/* 发出READ0命令 */
write_cmd(0);
/* Write Address */
write_addr(i);
wait_idle();
for(j=0; j < NAND_SECTOR_SIZE; j++, i++) {
*buf = read_data();
buf++;
}
}
/* 取消片选信号 */
nand_deselect_chip();
return ;
}
/* 读函数
* Large Page
*/
void nand_read_ll_lp(unsigned char *buf, unsigned long start_addr, int size)
{
int i, j;
if ((start_addr & NAND_BLOCK_MASK_LP) || (size & NAND_BLOCK_MASK_LP)) {
return ; /* 地址或长度不对齐 */
}
/* 选中芯片 */
nand_select_chip();
for(i=start_addr; i < (start_addr + size);) {
/* 发出READ0命令 */
write_cmd(0);
/* Write Address */
write_addr_lp(i);
write_cmd(0x30);
wait_idle();
for(j=0; j < NAND_SECTOR_SIZE_LP; j++, i++) {
*buf = read_data();
buf++;
}
}
/* 取消片选信号 */
nand_deselect_chip();
return ;
}
int bBootFrmNORFlash(void)
{
volatile unsigned int *pdw = (volatile unsigned int *)0;
unsigned int dwVal;
/*
* 无论是从NOR Flash还是从NAND Flash启动，
* 地址0处为指令"b Reset", 机器码为0xEA00000B，
* 对于从NAND Flash启动的情况，其开始4KB的代码会复制到CPU内部4K内存中，
* 对于从NOR Flash启动的情况，NOR Flash的开始地址即为0。
* 对于NOR Flash，必须通过一定的命令序列才能写数据，
* 所以可以根据这点差别来分辨是从NAND Flash还是NOR Flash启动:
* 向地址0写入一个数据，然后读出来，如果没有改变的话就是NOR Flash
*/
dwVal = *pdw;
*pdw = 0x12345678;
if (*pdw != 0x12345678)
{
return 1;
}
else
{
*pdw = dwVal;
return 0;
}
}
int CopyCode2Ram(unsigned long start_addr, unsigned char *buf, int size)
{
unsigned int *pdwDest;
unsigned int *pdwSrc;
int i;
if (bBootFrmNORFlash())
{
pdwDest = (unsigned int *)buf;
pdwSrc = (unsigned int *)start_addr;
/* 从 NOR Flash启动 */
for (i = 0; i < size / 4; i++)
{
pdwDest[i] = pdwSrc[i];
}
return 0;
}
else
{
/* 初始化NAND Flash */
nand_init_ll();
/* 从 NAND Flash启动 */
nand_read_ll_lp(buf, start_addr, (size + NAND_BLOCK_MASK_LP)&~(NAND_BLOCK_MASK_LP));
return 0;
}
}然后在 include\S3c24x0.h加入2440nand寄存器的定义：
/* NAND FLASH (see S3C2440 manual chapter 6, www.100ask.net) */
typedef struct {
S3C24X0_REG32 NFCONF;
S3C24X0_REG32 NFCONT;
S3C24X0_REG32 NFCMD;
S3C24X0_REG32 NFADDR;
S3C24X0_REG32 NFDATA;
S3C24X0_REG32 NFMECCD0;
S3C24X0_REG32 NFMECCD1;
S3C24X0_REG32 NFSECCD;
S3C24X0_REG32 NFSTAT;
S3C24X0_REG32 NFESTAT0;
S3C24X0_REG32 NFESTAT1;
S3C24X0_REG32 NFMECC0;
S3C24X0_REG32 NFMECC1;
S3C24X0_REG32 NFSECC;
S3C24X0_REG32 NFSBLK;
S3C24X0_REG32 NFEBLK;
} /*__attribute__((__packed__))*/ S3C2440_NAND;
到这里，将uboot烧写到nandflash上就可以启动了：
U-Boot 1.1.6 (Mar 22 2013 - 11:33:36) DRAM: 64 MB Flash: 512 kB *** Warning - bad CRC, using default environment In: serial Out: serial Err: serial SMDK2410 # SMDK2410 #