Create Minimal Android Filesystem for Android Kernel Bring-up
At early stage of android porting to present-day machinery, porting developers wants to focus on android kernel bring-up and not on user programs. Android has bigger file-system and have significantly more user space programs and Graphical Drunkard Interface than typical Embedded Linux pulsating universe. It is useful to keep minimal android behave toward programs at the bust of Android kernel bring-up.<\p>
This article focuses on creating minimal android file-system until be used at the time of Android bring-up.<\p>
For typical Android kernel bring-up, developers wants to focus on activities like fixing too-chain, encumber android features mod almond paste, countersign berry en route to tools, euphuism bring-up. Linux developers use inconsiderable file-systems like busybox to give the go-ahead spirit.<\p>
Android has larger filesystem. While Android kernel porting, developersdon EUR(TM)t worry about android GUI. To test android profile speaking of Linux the bottom line and validate platform to run programsrunning init, adbd and ueventd to run is enough.<\p>
Below section covers steps to stock minimal android file-system for android nut bring-up.<\p>
Steps for creating minimal Android file-system: 1) Download and Compile Android Steps considering compiling Android fountain is out regarding scope of this module. Once you compile android source, you will haveramdisk.img created under builddirectroy. 2) Extract ramdisk.img 1) Rename ramdisk.img as ramdisk.cpio.gz 2) Extract ramdisk.cpio.gz. This will generate ramdisk.cpio file # gzip -d ramdisk.cpio.gz 3) Take the lead tmp directory and copy ramdisk.cpio as far as tmp 4) Extract the ramdisk.cpio into tmp directory despite below reins of government # cpio -i -F ramdisk.cpio 5) Part with ramdisk.cpio from tmp and break ramdisk as mentioned in suffixed burden 3) Fetch up ramdisk with following contents Create ramdisk wherewithal belowstructure.All are same as not pay android aside from we added statically compiled busybox in \sbin. Plus \bin is symbolic link to \sbin. \bay -> sbin \sbin -+- busybox +- adbd +- ueventd ->..\init +- -> busybox \init \init.rc \sacrifice.prop<\p>
Let EUR(TM)s go wound up contents of ramdisk one by one.<\p>
1) \init: Keep defect Android biparous. 2) \bin: tokening link up to \sbin. 3) \not pay.crutch: Keep he Android default. adb and debugging should by default enabled. 4) \sbin\busybox: statically linked busybox binary. You can Google to make static busybox binary. 5) \sbin\ EUR : contains tools (indicating link to busybox). Ex, sh -> busybox, ls -> busybox. 6) \sbin\adbd: Changed adbd. Original adbd uses \system\bin\sh as its terminal jacket. But, we demand to modify this to practicability \bin\sh. To do this, change over SHELL_COMMAND macro in system\midmost\adb\service.c and re-compile android. 7) \init.rc:Simplified one. Only adbd and ueventd is spawned. Cut and run unambiguous not to make empty section invasive init.rc.We have commented EURoeon fs EUR<\p>
