4）准备进入u-boot的第二阶段（在u-boot中添加对我们开发板上NorFlash的支持）。
通常，在嵌入式bootloader中，有两种方式来引导启动内核：从NorFlash启动和从NandFlash启动。u-boot中默认是从NorFlash启动，再从上一节这个运行结果图中看，还发现几个问题：第一，我开发板的NorFlash是2M的，而这里显示的是512kB；第二，出现Warning-badCRC,usingdefaultenvironment的警告信息。不是u-boot默认是从NorFlash启动的吗？为什么会有这些错误信息呢？这是因为我们还没有添加对我们自己的Nor
Flash的支持，u-boot默认的是其他型号的NorFlash，而我们的NorFlash的型号是SST39VF1601。另外怎样将命令行提示符前面的SMDK2410变成我自己定义的呢？
下面我们一一来解决这些问题，让u-boot完全对我们NorFlash的支持。首先我们修改头文件代码如下：
#gedit
include/configs/my2440.h//修改命令行前的名字和NorFlash参数部分的定义
|
#defineCONFIG_SYS_PROMPT"[MY2440]#"//将命令行前的名字改成[MY2440]
/*-----------------------------------------------------------------------
*FLASHandenvironmentorganization
*/
#if0//注释掉下面两个类型的Nor
Flash设置，因为不是我们所使用的型号
#defineCONFIG_AMD_LV4001/*uncommentthisifyouhaveaLV400flash*/
#define
CONFIG_AMD_LV8001/*uncommentthisifyouhaveaLV800flash*/
#endif
#define
CONFIG_SYS_MAX_FLASH_BANKS1/*maxnumberofmemorybanks*/
#ifdefCONFIG_AMD_LV800
#define
PHYS_FLASH_SIZE0x00100000/*1MB*/
#define
CONFIG_SYS_MAX_FLASH_SECT(19)
/*maxnumberofsectorsononechip*/
#defineCONFIG_ENV_ADDR
(CONFIG_SYS_FLASH_BASE
+0x0F0000)
/*addrofenvironment*/
#endif
#ifdefCONFIG_AMD_LV400
#definePHYS_FLASH_SIZE0x00080000/*512KB*/
#defineCONFIG_SYS_MAX_FLASH_SECT(11)/*max
numberofsectorsononechip*/
#defineCONFIG_ENV_ADDR(CONFIG_SYS_FLASH_BASE
+0x070000)
/*addrofenvironment*/
#endif
#define
CONFIG_SST_39VF16011//添加mini2440开发板NorFlash设置
#define
PHYS_FLASH_SIZE0x200000//我们开发板的NorFlash是2M
#define
CONFIG_SYS_MAX_FLASH_SECT(512)//根据SST39VF1601的芯片手册描述，对其进行操作有两种方式：块方式和扇区方式。现采用扇区方式(sector)，1
sector=2Kword=4Kbyte，所以2M的NorFlash共有512个sector
#define
CONFIG_ENV_ADDR(CONFIG_SYS_FLASH_BASE
+0x040000)
//暂设置环境变量的首地址为0x040000(即：256Kb)
|
然后添加对我们mini2440开发板上2M的NorFlash(型号为SST39VF1601)的支持。在u-boot中对NorFlash的操作分别有初始化、擦除和写入，所以我们主要修改与硬件密切相关的三个函数flash_init、flash_erase、write_hword，修改代码如下：
#gedit
board/samsung/my2440/flash.c
|
//修改定义部分如下：
//#defineMAIN_SECT_SIZE0x10000
#defineMAIN_SECT_SIZE0x1000
//定义为4k，刚好是一个扇区的大小
//#defineMEM_FLASH_ADDR1(*(volatileu16*)(CONFIG_SYS_FLASH_BASE+(0x00000555<<1)))
//#defineMEM_FLASH_ADDR2(*(volatileu16*)(CONFIG_SYS_FLASH_BASE+(0x000002AA<<1)))
#defineMEM_FLASH_ADDR1(*(volatile
u16*)(CONFIG_SYS_FLASH_BASE
+
(0x00005555
<<1)))//这两个参数看SST39VF1601手册
#defineMEM_FLASH_ADDR2(*(volatile
u16*)(CONFIG_SYS_FLASH_BASE
+
(0x00002AAA
<<1)))
//修改flash_init函数如下：
#elifdefined(CONFIG_AMD_LV800)
(AMD_MANUFACT
&FLASH_VENDMASK)
|
(AMD_ID_LV800B
&FLASH_TYPEMASK);
#elif
defined(CONFIG_SST_39VF1601)//在CONFIG_AMD_LV800后面添加CONFIG_SST_39VF1601
(SST_MANUFACT
&FLASH_VENDMASK)
|
(SST_ID_xF1601
&FLASH_TYPEMASK);
for(j
=0;j<flash_info[i].sector_count;j++)
{
//if(j<=3){
///*1stoneis16KB*/
//if(j==0){
//flash_info[i].start[j]=
flashbase+0;
//}
///*2ndand3rdareboth8KB*/
//if((j==1)||(j==2)){
//flash_info[i].start[j]=
flashbase+0x4000+(j-
1)*
0x2000;
//}
///*4th32KB*/
//if(j==3){
//flash_info[i].start[j]=
flashbase+0x8000;
//}
//}else{
//flash_info[i].start[j]=flashbase+(j-3)*MAIN_SECT_SIZE;
//}
flash_info[i].start[j]
=flashbase
+j
*MAIN_SECT_SIZE;
}
//修改flash_print_info函数如下：
case
(AMD_MANUFACT&FLASH_VENDMASK):
printf
("AMD:");
break;
case
(SST_MANUFACT
&FLASH_VENDMASK)://添加SST39VF1601的
printf
("SST:
");
break;
case(AMD_ID_LV800B
&FLASH_TYPEMASK):
printf
("1xAmd29LV800BB(8Mbit)\n");
break;
case
(SST_ID_xF1601
&FLASH_TYPEMASK)://添加SST39VF1601的
printf("1xSST39VF1610
(16Mbit)\n");
break;
//修改flash_erase函数如下：
//if((info->flash_id&FLASH_VENDMASK)!=
//(AMD_MANUFACT&FLASH_VENDMASK)){
//returnERR_UNKNOWN_FLASH_VENDOR;
//}
if
((info->flash_id
&FLASH_VENDMASK)
!=
(SST_MANUFACT
&FLASH_VENDMASK))
{
returnERR_UNKNOWN_FLASH_VENDOR;
}
///*waituntilflashisready*/
//chip=0;
//do{
//result=*addr;
///*checktimeout*/
//if(get_timer_masked()>
//CONFIG_SYS_FLASH_ERASE_TOUT){
//MEM_FLASH_ADDR1=CMD_READ_ARRAY;
//chip=TMO;
//break;
//}
//if(!chip
//&&(result&0xFFFF)&BIT_ERASE_DONE)
//chip=READY;
//if(!chip
//&&(result&0xFFFF)&BIT_PROGRAM_ERROR)
//chip=ERR;
//}while(!chip);
//MEM_FLASH_ADDR1=CMD_READ_ARRAY;
//if(chip==ERR){
//rc=ERR_PROG_ERROR;
//gotooutahere;
//}
//if(chip==TMO){
//rc=ERR_TIMOUT;
//gotooutahere;
//}
while
(1)
{
if
((*addr
&0x40)
!=
(*addr
&0x40))
continue;
if
(*addr
&0x80)
{
rc=ERR_OK;
break;
}
}
//修改write_hword函数如下：
MEM_FLASH_ADDR1=CMD_UNLOCK1;
MEM_FLASH_ADDR2=CMD_UNLOCK2;
//MEM_FLASH_ADDR1=CMD_UNLOCK_BYPASS;
MEM_FLASH_ADDR1=CMD_PROGRAM;
//*addr=CMD_PROGRAM;
*addr=data;
///*waituntilflashisready*/
//chip=0;
//do{
//result=*addr;
///*checktimeout*/
//if(get_timer_masked()>CONFIG_SYS_FLASH_ERASE_TOUT){
//chip=ERR|TMO;
//break;
//}
//if(!chip&&((result&0x80)==(data&0x80)))
//chip=READY;
//if(!chip&&((result&0xFFFF)&BIT_PROGRAM_ERROR)){
//result=*addr;
//if((result&0x80)==(data&0x80))
//chip=READY;
//else
//chip=ERR;
//}
//}while(!chip);
//*addr=CMD_READ_ARRAY;
//if(chip==ERR||*addr!=data)
//rc=ERR_PROG_ERROR;
while
(1)
{
if
((*addr
&0x40)
!=
(*addr
&0x40))
continue;
if
((*addr
&0x80)
==
(data
&0x80))
{
rc=ERR_OK;
break;
}
}
|
#gedit
include/configs/my2440.h//修改命令行前的名字和NorFlash参数部分的定义
|
#defineCONFIG_SYS_PROMPT"[MY2440]#"//将命令行前的名字改成[MY2440]
/*-----------------------------------------------------------------------
*FLASHandenvironmentorganization
*/
#if0//注释掉下面两个类型的Nor
Flash设置，因为不是我们所使用的型号
#defineCONFIG_AMD_LV4001/*uncommentthisifyouhaveaLV400flash*/
#define
CONFIG_AMD_LV8001/*uncommentthisifyouhaveaLV800flash*/
#endif
#define
CONFIG_SYS_MAX_FLASH_BANKS1/*maxnumberofmemorybanks*/
#ifdefCONFIG_AMD_LV800
#define
PHYS_FLASH_SIZE0x00100000/*1MB*/
#define
CONFIG_SYS_MAX_FLASH_SECT(19)
/*maxnumberofsectorsononechip*/
#defineCONFIG_ENV_ADDR
(CONFIG_SYS_FLASH_BASE
+0x0F0000)
/*addrofenvironment*/
#endif
#ifdefCONFIG_AMD_LV400
#definePHYS_FLASH_SIZE0x00080000/*512KB*/
#defineCONFIG_SYS_MAX_FLASH_SECT(11)/*max
numberofsectorsononechip*/
#defineCONFIG_ENV_ADDR(CONFIG_SYS_FLASH_BASE
+0x070000)
/*addrofenvironment*/
#endif
#define
CONFIG_SST_39VF16011//添加mini2440开发板NorFlash设置
#define
PHYS_FLASH_SIZE0x200000//我们开发板的NorFlash是2M
#define
CONFIG_SYS_MAX_FLASH_SECT(512)//根据SST39VF1601的芯片手册描述，对其进行操作有两种方式：块方式和扇区方式。现采用扇区方式(sector)，1
sector=2Kword=4Kbyte，所以2M的NorFlash共有512个sector
#define
CONFIG_ENV_ADDR(CONFIG_SYS_FLASH_BASE
+0x040000)
//暂设置环境变量的首地址为0x040000(即：256Kb)
|
#gedit
board/samsung/my2440/flash.c
|
//修改定义部分如下：
//#defineMAIN_SECT_SIZE0x10000
#defineMAIN_SECT_SIZE0x1000
//定义为4k，刚好是一个扇区的大小
//#defineMEM_FLASH_ADDR1(*(volatileu16*)(CONFIG_SYS_FLASH_BASE+(0x00000555<<1)))
//#defineMEM_FLASH_ADDR2(*(volatileu16*)(CONFIG_SYS_FLASH_BASE+(0x000002AA<<1)))
#defineMEM_FLASH_ADDR1(*(volatile
u16*)(CONFIG_SYS_FLASH_BASE
+
(0x00005555
<<1)))//这两个参数看SST39VF1601手册
#defineMEM_FLASH_ADDR2(*(volatile
u16*)(CONFIG_SYS_FLASH_BASE
+
(0x00002AAA
<<1)))
//修改flash_init函数如下：
#elifdefined(CONFIG_AMD_LV800)
(AMD_MANUFACT
&FLASH_VENDMASK)
|
(AMD_ID_LV800B
&FLASH_TYPEMASK);
#elif
defined(CONFIG_SST_39VF1601)//在CONFIG_AMD_LV800后面添加CONFIG_SST_39VF1601
(SST_MANUFACT
&FLASH_VENDMASK)
|
(SST_ID_xF1601
&FLASH_TYPEMASK);
for(j
=0;j<flash_info[i].sector_count;j++)
{
//if(j<=3){
///*1stoneis16KB*/
//if(j==0){
//flash_info[i].start[j]=
flashbase+0;
//}
///*2ndand3rdareboth8KB*/
//if((j==1)||(j==2)){
//flash_info[i].start[j]=
flashbase+0x4000+(j-
1)*
0x2000;
//}
///*4th32KB*/
//if(j==3){
//flash_info[i].start[j]=
flashbase+0x8000;
//}
//}else{
//flash_info[i].start[j]=flashbase+(j-3)*MAIN_SECT_SIZE;
//}
flash_info[i].start[j]
=flashbase
+j
*MAIN_SECT_SIZE;
}
//修改flash_print_info函数如下：
case
(AMD_MANUFACT&FLASH_VENDMASK):
printf
("AMD:");
break;
case
(SST_MANUFACT
&FLASH_VENDMASK)://添加SST39VF1601的
printf
("SST:
");
break;
case(AMD_ID_LV800B
&FLASH_TYPEMASK):
printf
("1xAmd29LV800BB(8Mbit)\n");
break;
case
(SST_ID_xF1601
&FLASH_TYPEMASK)://添加SST39VF1601的
printf("1xSST39VF1610
(16Mbit)\n");
break;
//修改flash_erase函数如下：
//if((info->flash_id&FLASH_VENDMASK)!=
//(AMD_MANUFACT&FLASH_VENDMASK)){
//returnERR_UNKNOWN_FLASH_VENDOR;
//}
if
((info->flash_id
&FLASH_VENDMASK)
!=
(SST_MANUFACT
&FLASH_VENDMASK))
{
returnERR_UNKNOWN_FLASH_VENDOR;
}
///*waituntilflashisready*/
//chip=0;
//do{
//result=*addr;
///*checktimeout*/
//if(get_timer_masked()>
//CONFIG_SYS_FLASH_ERASE_TOUT){
//MEM_FLASH_ADDR1=CMD_READ_ARRAY;
//chip=TMO;
//break;
//}
//if(!chip
//&&(result&0xFFFF)&BIT_ERASE_DONE)
//chip=READY;
//if(!chip
//&&(result&0xFFFF)&BIT_PROGRAM_ERROR)
//chip=ERR;
//}while(!chip);
//MEM_FLASH_ADDR1=CMD_READ_ARRAY;
//if(chip==ERR){
//rc=ERR_PROG_ERROR;
//gotooutahere;
//}
//if(chip==TMO){
//rc=ERR_TIMOUT;
//gotooutahere;
//}
while
(1)
{
if
((*addr
&0x40)
!=
(*addr
&0x40))
continue;
if
(*addr
&0x80)
{
rc=ERR_OK;
break;
}
}
//修改write_hword函数如下：
MEM_FLASH_ADDR1=CMD_UNLOCK1;
MEM_FLASH_ADDR2=CMD_UNLOCK2;
//MEM_FLASH_ADDR1=CMD_UNLOCK_BYPASS;
MEM_FLASH_ADDR1=CMD_PROGRAM;
//*addr=CMD_PROGRAM;
*addr=data;
///*waituntilflashisready*/
//chip=0;
//do{
//result=*addr;
///*checktimeout*/
//if(get_timer_masked()>CONFIG_SYS_FLASH_ERASE_TOUT){
//chip=ERR|TMO;
//break;
//}
//if(!chip&&((result&0x80)==(data&0x80)))
//chip=READY;
//if(!chip&&((result&0xFFFF)&BIT_PROGRAM_ERROR)){
//result=*addr;
//if((result&0x80)==(data&0x80))
//chip=READY;
//else
//chip=ERR;
//}
//}while(!chip);
//*addr=CMD_READ_ARRAY;
//if(chip==ERR||*addr!=data)
//rc=ERR_PROG_ERROR;
while
(1)
{
if
((*addr
&0x40)
!=
(*addr
&0x40))
continue;
if
((*addr
&0x80)
==
(data
&0x80))
{
rc=ERR_OK;
break;
}
}
|
修改完后重新编译u-boot，下载到RAM中运行结果如下图：
从运行结果图看，NorFlash的大小可以正确检测到了，命令行前面的名字也由原来的SMDK2410改成我自己定义的[MY2440]了，但是还会出现badCRC的警告信息，其实这并不是什么问题，只是还没有将环境变量设置到NorFlash中，我们执行一下u-boot的：saveenv命令就可以了。如下图：
再重新下载u-boot.bin文件到RAM中运行，可以观察到不会出现警告信息了，这时候u-boot已经对我们开发板上的NorFlash完全支持了。如下：
