全志partition分区
partitions参数
[partition_start]
;------------------------------>mmcblk0p2/nanda
[partition]
name = bootloader
size = 65536
downloadfile = "boot-resource.fex"
user_type = 0x8000
;------------------------------>mmcblk0p5/nandb
[partition]
name = env
size = 32768
downloadfile = "env.fex"
user_type = 0x8000
;------------------------------>mmcblk0p6/nandc
[partition]
name = boot
size = 32768
downloadfile = "boot.fex"
user_type = 0x8000
;------------------------------>mmcblk0p7/nandd
[partition]
name = system
size = 4194304
downloadfile = "system.fex"
user_type = 0x8000
- 生成sunxi_mbr.fex 供打包烧录用。
brandy/pack_tools/create_mbr -
- uboot 中分析sys_partition.fex 第一个partition mmcblk0p2 ，最后一个mmcblk0p1 UDISK
for(index = 0; index < part_total && index < SUNXI_MBR_MAX_PART_COUNT; index++)
{
sunxi_partition_get_name(index, &fb_part.name[0]);
fb_part.start = sunxi_partition_get_offset(index) * 512;
fb_part.length = sunxi_partition_get_size(index) * 512;
fb_part.flags = 0;
printf("%-12s: %-12x %-12x\n", fb_part.name, fb_part.start, fb_part.length);
memset(part_name, 0, 16);
if(!storage_type)
{
sprintf(part_name, "nand%c", 'a' + index);
}
else
{
if(index == 0)
{
strcpy(part_name, "mmcblk0p2");
}
else if( (index+1)==part_total)
{
strcpy(part_name, "mmcblk0p1");
}
else
{
sprintf(part_name, "mmcblk0p%d", index + 4);
}
}
cmdline参数
boot_type=2 disp_para=2 fb_base=0x0 config_size=40640 androidboot.serialno=882c9f98b78700000000 \
androidboot.hardware=sun8i console=ttyS0,115200 root=/dev/mmcblk0p7 init=/init ion_cma_list=120m,256m loglevel=6 \
partitions=bootloader@mmcblk0p2:env@mmcblk0p5:boot@mmcblk0p6:system@mmcblk0p7:misc@mmcblk0p8:recovery@mmcblk0p9:cache@mmcblk0p10:metadata@mmcblk0p11:private@mmcblk0p12:frp@mmcblk0p13:empty@mmcblk0p14:alog@mmcblk0p15:media_data@mmcblk0p16:UDISK@mmcblk0p1
kernel检测加载分区
Device Boot Start End Blocks Id System
/dev/block/mmcblk0p1 * 397825 483328 684032 b Win95 FAT32
Partition 1 does not end on cylinder boundary
/dev/block/mmcblk0p2 4609 8704 32768 6 FAT16
Partition 2 does not end on cylinder boundary
/dev/block/mmcblk0p3 1 389121 3112960 5 Extended
Partition 3 does not end on cylinder boundary
/dev/block/mmcblk0p5 8705 10752 16384 83 Linux
/dev/block/mmcblk0p6 10753 12800 16384 83 Linux
/dev/block/mmcblk0p7 12801 274944 2097152 83 Linux
/dev/block/mmcblk0p8 274945 276992 16384 83 Linux
/dev/block/mmcblk0p9 276993 281088 32768 83 Linux
/dev/block/mmcblk0p10 281089 379392 786432 83 Linux
/dev/block/mmcblk0p11 379393 381440 16384 83 Linux
/dev/block/mmcblk0p12 381441 383488 16384 83 Linux
/dev/block/mmcblk0p13 383489 383552 512 83 Linux
/dev/block/mmcblk0p14 383553 385536 15872 83 Linux
/dev/block/mmcblk0p15 385537 395776 81920 83 Linux
/dev/block/mmcblk0p16 395777 397824 16384 83 Linux
struct parsed_partitions *
check_partition(struct gendisk *hd, struct block_device *bdev)
{
struct parsed_partitions *state;
int i, res, err;
state = kzalloc(sizeof(struct parsed_partitions), GFP_KERNEL);
if (!state)
return NULL;
state->pp_buf = (char *)__get_free_page(GFP_KERNEL);
if (!state->pp_buf) {
kfree(state);
return NULL;
}
state->pp_buf[0] = '\0';
state->bdev = bdev;
disk_name(hd, 0, state->name);
snprintf(state->pp_buf, PAGE_SIZE, " %s:", state->name);
if (isdigit(state->name[strlen(state->name)-1]))
sprintf(state->name, "p");
state->limit = disk_max_parts(hd);
i = res = err = 0;
while (!res && check_part[i]) {
memset(&state->parts, 0, sizeof(state->parts));
res = check_part[i++](state);
if (res < 0) {
/* We have hit an I/O error which we don't report now.
* But record it, and let the others do their job.
*/
err = res;
res = 0;
}
}
if (res > 0) {
printk(KERN_INFO "%s", state->pp_buf);
free_page((unsigned long)state->pp_buf);
return state;
}
if (state->access_beyond_eod)
err = -ENOSPC;
if (err)
/* The partition is unrecognized. So report I/O errors if there were any */
res = err;
if (!res)
strlcat(state->pp_buf, " unknown partition table\n", PAGE_SIZE);
else if (warn_no_part)
strlcat(state->pp_buf, " unable to read partition table\n", PAGE_SIZE);
printk(KERN_INFO "%s", state->pp_buf);
free_page((unsigned long)state->pp_buf);
kfree(state);
return ERR_PTR(res);
}
byname
/dev/block/bootdevice/by-name/xxx，目录及后面的链接是init进程中创建出来的，init收到增加新分区的uevent事件后，构造出以上by-name下的文件.
std::ifstream cmdline_fin("/proc/cmdline");
if (getline(cmdline_fin, cmdline)) {
std::string partname = find_partition_name(cmdline, uevent->device_name);
if (partname.length() > 0) {
if (asprintf(&links[link_num], "/dev/block/by-name/%s", partname.c_str()) > 0)
link_num++;
else
links[link_num] = NULL;
}
}
lrwxrwxrwx root root 1970-01-01 08:00 UDISK -> /dev/block/mmcblk0p1
lrwxrwxrwx root root 1970-01-01 08:00 alog -> /dev/block/mmcblk0p15
lrwxrwxrwx root root 1970-01-01 08:00 boot -> /dev/block/mmcblk0p6
lrwxrwxrwx root root 1970-01-01 08:00 bootloader -> /dev/block/mmcblk0p2
lrwxrwxrwx root root 1970-01-01 08:00 cache -> /dev/block/mmcblk0p10
lrwxrwxrwx root root 1970-01-01 08:00 empty -> /dev/block/mmcblk0p14
lrwxrwxrwx root root 1970-01-01 08:00 env -> /dev/block/mmcblk0p5
lrwxrwxrwx root root 1970-01-01 08:00 frp -> /dev/block/mmcblk0p13
lrwxrwxrwx root root 1970-01-01 08:00 media_data -> /dev/block/mmcblk0p16
lrwxrwxrwx root root 1970-01-01 08:00 metadata -> /dev/block/mmcblk0p11
lrwxrwxrwx root root 1970-01-01 08:00 misc -> /dev/block/mmcblk0p8
lrwxrwxrwx root root 1970-01-01 08:00 private -> /dev/block/mmcblk0p12
lrwxrwxrwx root root 1970-01-01 08:00 recovery -> /dev/block/mmcblk0p9
lrwxrwxrwx root root 1970-01-01 08:00 system -> /dev/block/mmcblk0p7