发布时间 : 星期二 文章移植Linux内核到norflash更新完毕开始阅读
for(; !mymtd && *type; type++) {
mymtd = do_map_probe(*type, &at91rm9200nor_map); }
if (mymtd) {
mymtd->owner = THIS_MODULE;
#ifdef CONFIG_MTD_PARTITIONS
mtd_parts_nb = parse_mtd_partitions(mymtd, probes, &mtd_parts, 0);
if (mtd_parts_nb > 0) part_type = \;
if (mtd_parts_nb == 0) {
mtd_parts = at91rm9200nor_partitions; mtd_parts_nb = ARRAY_SIZE(at91rm9200nor_partitions);
part_type = \; } #endif
add_mtd_device(mymtd); if (mtd_parts_nb == 0)
printk(KERN_NOTICE MSG_PREFIX \partition info available\\n\);
else {
printk(KERN_NOTICE MSG_PREFIX
\%s partition definition\\n\, part_type);
//mymtd为master mtd_info它不被添加到数组mtd_table[]中，它只用于初始化 //每一个分区的mtd_info。而后将每一个分区对应的mtd_info添加到数组mtd_table[] //供上层调用。MTD原始设备驱动层的主要工作就是向 mtd_table[]中添加mtd_info。
add_mtd_partitions(mymtd, mtd_parts, mtd_parts_nb);
}
return 0; }
iounmap((void *)at91rm9200nor_map.virt); return -ENXIO; }
static void __exit cleanup_at91rm9200nor(void) {
if (mymtd) {
del_mtd_device(mymtd); map_destroy(mymtd); }
if (at91rm9200nor_map.virt) {
iounmap((void *)at91rm9200nor_map.virt); at91rm9200nor_map.virt = 0; } }
module_init(init_at91rm9200nor); module_exit(cleanup_at91rm9200nor);
MODULE_LICENSE(\);
MODULE_AUTHOR(\Groeger
MODULE_DESCRIPTION(\configurable MTD map driver\);
（3）配置内核
增加MTD，和相应的文件系统的支持。
Devices Drivers --->
Memory Technology Devices (MTD) --->
<*> Memory Technology Device(MTD) support <*> MTD partitioning support
<*> Direct char device access to MTD devices <*> Caching block device access to MTD devices RAM/ROM/Flash chip drivers --->
<*> Detect flash chips by Common Flash Interface(CFI) probe <*> Support for Intel/Sharp flash chips Mapping drivers for chip access ---> <*> CFI Flash device mapped on AT91RM9200 File Systems --->
Miscellaneous filesystems --->
<*>Journalling Flash File System v2 (JFFS2) support
<*>Compressed ROM file system support (cramfs)
这里选择cramfs或者Jffs2的支持。
（4）编译，然后加载
make Image编译，然后制作成uImage。
这是JFFS2作为根文件系统的信息：
TOPDIR=$($(which pwd)) TMP=$TOPDIR/linux.bin TARGET=$TOPDIR/uImage
arm-linux-objcopy -O binary -S vmlinux $TMP && gzip -v9 $TMP && \\ mkimage -n 'RAM disk' -A arm -O linux -T kernel -C gzip \\
-a 0x20008000 -e 0x20008000 -d $TMP.gz $TARGET && \\ cp $TARGET /mnt/hgfs/common && \\ rm -f $TMP*
可以看到MTD分区信息。进入shell界面，然后查看/proc/mtd，如下：
AT91RM9200-NOR:0x00800000 at 0x10000000
NOR flash on AT91RM9200DK: Found 1 x16 devices at 0x0 in 16-bit bank Intel/Sharp Extended Query Table at 0x0031 Using buffer write method
cfi_cmdset_0001: Erase suspend on write enabled AT91RM9200-NOR:using static partition definition
Creating 5 MTD partitions on \flash on AT91RM9200DK\: 0x00000000-0x00020000 : \ 0x00020000-0x00220000 : \ 0x00220000-0x00520000 : \ 0x00520000-0x007e0000 : \ 0x007e0000-0x00800000 : \
可以看到加载是正确的。