emmc 存储

linux下emmc信息获取

Posted by 婷 on July 17, 2024 本文总阅读量次

简介

主要介绍下linux下emmc（延伸到块设备）信息的获取

/proc/partition接口

这是我们的板子显示的内容，这里的block的单位是KB，一开始我以为是512byte

img

对比这里的大小信息可以跟上面的信息对应

img

如果是cmdline传参，给分区设置名字的话，还会显示

img

mount查看分区挂载情况

执行mount命令，可以查看分区挂载的情况。

img

fdisk -l

输入fdisk -l这个命令

img

可以看到能显示具体的type

img

lsblk

lsblk命令的输出可以看到boot ,rpmb, uda分区都是 type disk的，而uda里面各自的分区显示的是part，这个其实跟内核块设备驱动中的mmc_add_disk跟mmc_blk_alloc_part相关，后面会分析到的

img

/sys/class/block 查看eMMC分区情况

在 /sys/class/block/ 目录下可以查看当前系统的分区情况：

img

root@copyright:/sys/class/block# ls
loop0  loop4  mmcblk1       mmcblk1p2    ram10  ram14  ram4  ram8
loop1  loop5  mmcblk1boot0  mmcblk1rpmb  ram11  ram15  ram5  ram9
loop2  loop6  mmcblk1boot1  ram0         ram12  ram2   ram6
loop3  loop7  mmcblk1p1     ram1         ram13  ram3   ram7
root@copyright:/sys/class/block# ls -l mmc*
lrwxrwxrwx 1 root root 0 Jan  1  1970 mmcblk1 -> ../../devices/platform/soc/2100000.aips-bus/2194000.usdhc/mmc_host/mmc1/mmc1:0001/block/mmcblk1
lrwxrwxrwx 1 root root 0 Jan  1  1970 mmcblk1boot0 -> ../../devices/platform/soc/2100000.aips-bus/2194000.usdhc/mmc_host/mmc1/mmc1:0001/block/mmcblk1/mmcblk1boot0
lrwxrwxrwx 1 root root 0 Jan  1  1970 mmcblk1boot1 -> ../../devices/platform/soc/2100000.aips-bus/2194000.usdhc/mmc_host/mmc1/mmc1:0001/block/mmcblk1/mmcblk1boot1
lrwxrwxrwx 1 root root 0 Jan  1  1970 mmcblk1p1 -> ../../devices/platform/soc/2100000.aips-bus/2194000.usdhc/mmc_host/mmc1/mmc1:0001/block/mmcblk1/mmcblk1p1
lrwxrwxrwx 1 root root 0 Jan  1  1970 mmcblk1p2 -> ../../devices/platform/soc/2100000.aips-bus/2194000.usdhc/mmc_host/mmc1/mmc1:0001/block/mmcblk1/mmcblk1p2
lrwxrwxrwx 1 root root 0 Jan  1  1970 mmcblk1rpmb -> ../../devices/platform/soc/2100000.aips-bus/2194000.usdhc/mmc_host/mmc1/mmc1:0001/block/mmcblk1/mmcblk1rpmb
root@copyright:/sys/class/block#

从上面的信息可以知道：

  • 这个eMMC上总共共有5个分区，boot0/boot1/rpmb/p1/p2分区；
  • 这个eMMC用到的控制器为2194000.usdhc；
  • 我们可以到软连接显示的../../devices/platform/soc/2100000.aips-bus/2194000.usdhc/mmc_host/mmc1/mmc1:0001/block/mmcblk1/目录下查看更具体的信息；

img

目录下还有我们boot，rpmb，uda分区的信息

img

关于这些参数的意义，可以参考如下两个链接

https://www.kernel.org/doc/Documentation/ABI/testing/sysfs-block
https://www.kernel.org/doc/Documentation/block/stat.txt

这里简单的现实下几个特性，这里的mmc1:0001表示mmc1控制器，rca地址为0001的emmc卡

下面看了hwrev，name，oemid，raw_rpmb_size_mult，csd，cid，erase_size，enhanced_area_size，enhanced_area_offset，fwrev，type，date

img

查看各个分区的大小

两种方法，一种是fdisk/lsblk，一种是sysfs

fdisk / lsblk

fdisk显示了start,end,sector

img

img

sysfs

另一种是sysfs的方法

uda分区

在/sys/devices/platform/soc/2100000.aips-bus/2194000.usdhc/mmc_host/mmc1/mmc1:0001/block目录下，有几个以mmcblk1开头的目录名，这里面包含了分区的起始和block的块数

img

  • 以mmcblk1p1为例，这里的start单位是block，也就是第2048块，size是65536，也就是p1分区大小为65536*512byte = 32MB
  • 以mmcblk1p2为例，这里的start单位是block，也就是第67584块，size是15202304，也就是p2分区大小为15202304*512byte = 7423MB

跟前面fdsik /lsblk 显示的信息是一样的，且这里可以看到p1开始前面有部分区域是空的，放了个分区表（注意分区管理只针对uda分区）

像如果是gpt分区的话，fdisk中的disklabel type会显示gpt

img

boot分区

没有start，只有size

img

rpmb分区

一样

img

读取emmc控制器

首先执行：mount -t debugfs none /sys/kernel/debug/， 在/sys/kernel/debug/mmc1目录下，cat ios可以查看这个eMMC控制器的工作频率和位宽基本信息。

img

像这里的mmc0是控制器的信息，而不是外接的emmc卡信息哦，emmc卡信息是mmc0:0001这种带地址的，这里也是有个host，device的思想

img

读取ext_csd寄存器

这个寄存器属于csd扩展出来的，需要将debugfs挂载出来才能读取到。注意这里读的是emmc卡的信息，相当于device了。

在/sys/kernel/debug/mmc1/mmc1\:0001/目录下就可以看到ext_csd寄存器了。cat ext_csd可以得到一个512字节大小的数据，如下

img

当然这样看很难看，无法很快的确认寄存器中某些位的值。因此，网上就有个小哥写了个python脚本来解析这512字节的数据，以常人可以理解的格式进行解析。详见此链接

脚本这里就先贴出来，其中的ecsd_str字符串要换成我们图片上的这些字符串

#!/usr/bin/env python
"""
Author: Kyle Manna <kyle@kylemanna.com>
Blog: https://blog.kylemanna.com
"""
import binascii
import re
import sys

def str2bytearray(s):
    if len(s) % 2:
        s = '0' + s

    reorder = True
    if reorder:
        r = []
        i = 1
        while i <= len(s):
            r.append(s[len(s) - i - 1])
            r.append(s[len(s) - i])
            i += 2
        s = ''.join(r)

    out = binascii.unhexlify(s)

    return out


if __name__ == '__main__':

    ecsd_str = '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'
    #ecsd_str = '320100'
    ecsd = str2bytearray(ecsd_str)
    csd_len = len(ecsd)

    line_len = 16
    i = 0
    while i < len(ecsd):
        sys.stdout.write("{0:04d}:\t".format(i))
        for j in range(line_len):
            if (i < csd_len):
                sys.stdout.write("{0:=02x}".format(ord(ecsd[csd_len-i-1])))
                i = i + 1
            else:
                break

            if (j == (line_len - 1)): pass
            elif (i % 4): sys.stdout.write(" ")
            else: sys.stdout.write("   ")

        sys.stdout.write("\n")

    print "BOOT_SIZE_MULTI[226] = 0x{:x}".format(ord(ecsd[csd_len-168-1]))

复制然后放到我们板子执行

image-20240728212920574

这里解析了很多信息出来，结合spec可以更仔细的看

root@copyright:~# ./parse_emmc.py
0000:   00 00 00 00   00 00 00 00   00 00 00 00   00 00 00 00
0016:   39 00 00 00   00 00 00 00   00 00 00 00   00 00 00 00
0032:   00 01 01 00   00 00 00 00   00 00 00 00   00 00 00 00
0048:   00 00 00 00   00 00 00 00   00 00 00 00   00 00 00 00
0064:   0f 00 00 c8   c8 00 00 00   00 00 00 00   00 00 00 00
0080:   00 00 00 00   00 01 00 00   00 00 00 00   00 00 00 00
0096:   00 00 00 00   00 05 00 00   00 00 00 00   00 00 00 00
0112:   00 00 00 00   00 00 00 00   00 00 00 00   00 00 00 00
0128:   00 00 01 00   00 00 00 00   00 00 00 00   00 00 00 00
0144:   00 00 00 00   00 00 00 00   00 00 00 00   00 d2 01 00
0160:   07 01 00 00   00 00 14 1f   04 00 00 00   00 00 00 00
0176:   00 00 00 48   00 00 00 00   01 02 00 00   00 00 00 00
0192:   08 00 02 00   57 1f 0a 02   00 00 00 00   00 00 00 00
0208:   00 00 00 01   00 00 e9 00   07 11 00 07   07 10 01 01
0224:   01 07 20 00   07 11 1b 55   02 00 00 00   00 00 00 00
0240:   00 1e 00 00   00 00 00 3c   0a 00 00 01   00 00 06 00
0256:   00 00 00 00   00 00 00 00   01 08 00 01   01 01 00 00
0272:   00 00 00 00   00 00 00 00   00 00 00 00   00 00 00 00
0288:   00 00 00 00   00 00 00 00   00 00 00 00   00 00 00 00
0304:   00 00 00 0f   01 00 00 00   00 00 00 00   00 00 00 00
0320:   00 00 00 00   00 00 00 00   00 00 00 00   00 00 00 00
0336:   00 00 00 00   00 00 00 00   00 00 00 00   00 00 00 00
0352:   00 00 00 00   00 00 00 00   00 00 00 00   00 00 00 00
0368:   00 00 00 00   00 00 00 00   00 00 00 00   00 00 00 00
0384:   00 00 00 00   00 00 00 00   00 00 00 00   00 00 00 00
0400:   00 00 00 00   00 00 00 00   00 00 00 00   00 00 00 00
0416:   00 00 00 00   00 00 00 00   00 00 00 00   00 00 00 00
0432:   00 00 00 00   00 00 00 00   00 00 00 00   00 00 00 00
0448:   00 00 00 00   00 00 00 00   00 00 00 00   00 00 00 00
0464:   00 00 00 00   00 00 00 00   00 00 00 00   00 00 00 00
0480:   00 00 00 00   00 00 00 00   00 81 c7 00   00 03 03 07
0496:   05 00 02 01   3f 3f 01 01   01 00 00 00   00 00 00 00
BOOT_SIZE_MULTI[226] = 0x4
root@copyright:~#

img

mmc工具

获取extcsd的信息

mmc extcsd read /dev/mmcblk0

img

img

检查enhance的最大大小

mmc extcsd read /dev/mmcblk0 | grep MAX_ENH_SIZE_MULT -A 1

img

MiB跟MB的区别

img

参考链接

CATALOG
    FEATURED TAGS
    Ubuntu markdown stm32 OSDK 飞控 串口 Jscope C C++ bin J-Flash 字符串 指针数组 malloc vscode svg png github python CMake CMakeLists Linux 拷贝构造函数 GIF 录屏 docker 操作系统 make Makefile 文件操作 DSP CCS SQL MySQL shell bochs 计算机网络 win10 SMTP Socket iOS uxplay 投屏 证书错误 apt nodesource ELF Typora 图床 fossil sql git SecureCRT windows cygwin blog alsa alsa-utils alsa-lib 音频 USB 链接文件 内存 mmap tcpdump 交叉编译 网络 防火墙 crontab bond Linux性能 udev linux pcie wsl2 MMIO wsl qemu raspi4 gdb ssh tun tap ifconfig 打印 gmac phy vim 组播 rock3a win11 usb sd ubuntu iptables netfilter wifi veth ipv6 wireshark radvd dhcpv6 dhcpv4 网络命名空间 br虚拟网卡 NDP emmc 存储 raspi4b baremental jtag buildroot rootfs ext4 调试 uboot dropbear raspi ebpf uart baremetal kernel bringup libbpf arm64 fit gzip 压缩 initcall_debug bootargs I2C