1.源码获取 这里不说了。 （一说就伤心，我伟大的和谐政府） 2.获取硬件驱动Google提供的所有 Nexus系列设备的硬件驱动的二进制文件在以下网址中均可下载
https://developers.google.com/android/nexus找到（我的是nexus5,你的自己选择，源码是4.4）
Nexus 5 (GSM/LTE) binaries for Android 4.4 (KRT16M)
| Hardware Component | Company | Download | MD5 Checksum | SHA-1 Checksum |
|---|
| NFC, Bluetooth, Wi-Fi | Broadcom | Link | bc912bc141f63859e37f59e1bfa1639b | 896abf0ba601d261b368e1ac5504dee846447ea1 |
| Camera, Sensors, Audio | LG | Link | c27922b7aeb0f0f85fdeba160b143368 | 78d36576ff70fe766144e19e48a22920b8a52afb |
| Graphics, GSM, Camera, GPS, Sensors, Media, DSP, USB | Qualcomm | Link | c2a05e15773adebf45955a97a5271dc8 | a5db0602f04ee5991dad387cd602f570a1e50929 |
下载完成后将三个压缩包解压至Android源码根目录（WORKING_DIRECTORY），得到三个.sh文件extract-broadcom-hammerhead.sh、extract-broadcom-hammerhead.sh、extract-broadcom-hammerhead.sh，分别执行这三个shell脚本（会提示是否接受License之类的，IACCEPT即 可），会在源码目录下新生成一个/vendor目录，里面就是Nexus5所需的相关硬件驱动二进制文件（一定要在编译Android源码前确保在源码根目录有官方提供的硬件驱动目录vendor，否则编译完成烧录后reboot会因为缺少硬件驱动卡在Google启动画面上）3.编译Android源码初始化编译环境执行初始化编译环境的脚本：注（在源码根目录WORKING_DIRECTORY）kevint@kevintcl:WORKING_DIRECTORY$
source build/envsetup.shincluding device/asus/tilapia/vendorsetup.sh including device/asus/grouper/vendorsetup.sh including device/asus/deb/vendorsetup.sh including device/asus/flo/vendorsetup.sh including device/generic/x86/vendorsetup.sh including device/generic/armv7-a-neon/vendorsetup.sh including device/generic/mips/vendorsetup.sh including device/samsung/manta/vendorsetup.sh including device/lge/mako/vendorsetup.sh including device/lge/hammerhead/vendorsetup.sh including sdk/bash_completion/adb.bash kevint@kevintcl:WORKING_DIRECTORY$ 列出所有可用的Targetkevint@kevintcl:WORKING_DIRECTORY$
lunch You're building on Linux Lunch menu... pick a combo: 1. aosp_arm-eng 2. aosp_x86-eng 3. aosp_mips-eng 4. vbox_x86-eng 5. aosp_tilapia-userdebug 6. aosp_grouper-userdebug 7. aosp_deb-userdebug 8. aosp_flo-userdebug 9. mini_x86-userdebug 10. mini_armv7a_neon-userdebug 11. mini_mips-userdebug 12. aosp_manta-userdebug 13. aosp_mako-userdebug
14. aosp_hammerhead-userdebug (这是我需要的） 选择一个Target使用lunch指令制定编译的target，具体的配置可以通过参数来指定，例如：
$lunch aosp_arm
-
eng
这行指令用来编译一个完整的模拟器emulator，所有的debug都是开启的。所有的target形式都是BUILD-BUILDTYPE，其中BUILD是一个特定代码集合的名称，如Nexus5的代码名称就是hammerhead。BUILDTYPE即编译的模式，有一下三种：
eng | This is the default flavor(原版). A plain(普通) [code]make is the same as make eng .Installs modules tagged with: eng , debug , user , and/or development .Installs non-APK modules that have no tags specified.Installs APKs according to the product definition files, in addition to tagged APKs.ro.secure=0 ro.debuggable=1 ro.kernel.android.checkjni=1 adb is enabled by default. |
user | [code]make userThis is the flavor intended to be the final release bits.Installs modules tagged with user .Installs non-APK modules that have no tags specified.Installs APKs according to the product definition files; tags are ignored for APK modules.ro.secure=1 ro.debuggable=0 adb is disabled by default. |
userdebug | [code]make userdebugThe same as user , except:Also installs modules tagged with debug .ro.debuggable=1 adb is enabled by default. |
如果你编译了某种特殊(flavor)的版本，然后要编译其它特殊版本，你必须在两次执行 make 之间执行 makeinstallclean 来担保(guarantee)你不会使用前一个特殊版本安装的文件。makeclean 同样可以满足要求（suffice），但是将会消耗更多的时间。注：由于我的编译的类型中没有eng , 我又想使ro.secure=0. 我做了如下修改kevint@kevintcl:core$ pwd /home/kevint/WORKING_DIRECTORY/build/core kevint@kevintcl:core$ vi main.mk 在如下位子ifneq (,$(user_variant)) # Target is secure in user builds. #ADDITIONAL_DEFAULT_PROPERTIES += ro.secure=1 在行被注释，添加了下行 ADDITIONAL_DEFAULT_PROPERTIES += ro.secure=
0 Which would you like? [aosp_arm-eng] ^C kevint@kevintcl:WORKING_DIRECTORY$ clear选择一个 Target （我的源码中只能用这个选项）kevint@kevintcl:WORKING_DIRECTORY$
lunch aosp_hammerhead-userdebug============================================ PLATFORM_VERSION_CODENAME=REL PLATFORM_VERSION=4.4 TARGET_PRODUCT=aosp_hammerhead TARGET_BUILD_VARIANT=userdebug TARGET_BUILD_TYPE=release TARGET_BUILD_APPS= TARGET_ARCH=arm TARGET_ARCH_VARIANT=armv7-a-neon TARGET_CPU_VARIANT=krait HOST_ARCH=x86 HOST_OS=linux HOST_OS_EXTRA=Linux-3.11.0-12-generic-x86_64-with-Ubuntu-13.10-saucy HOST_BUILD_TYPE=release BUILD_ID=KRT16S OUT_DIR=out ============================================ kevint@kevintcl:WORKING_DIRECTORY$ 开始编译如果你编译了某种特殊(flavor)的版本，然后要编译其它特殊版本，你必须在两次执行 make 之间执行 makeinstallclean 来担保(guarantee)你不会使用前一个特殊版本安装的文件。makeclean 同样可以满足要求（suffice），但是将会消耗更多的时间。kevint@kevintcl:WORKING_DIRECTORY$
make -j4 ============================================ PLATFORM_VERSION_CODENAME=REL PLATFORM_VERSION=4.4 TARGET_PRODUCT=aosp_hammerhead TARGET_BUILD_VARIANT=userdebug TARGET_BUILD_TYPE=release TARGET_BUILD_APPS= TARGET_ARCH=arm TARGET_ARCH_VARIANT=armv7-a-neon TARGET_CPU_VARIANT=krait HOST_ARCH=x86 HOST_OS=linux HOST_OS_EXTRA=Linux-3.11.0-12-generic-x86_64-with-Ubuntu-13.10-saucy HOST_BUILD_TYPE=release BUILD_ID=KRT16S OUT_DIR=out ============================================编译完成后生成的文件kevint@kevintcl:hammerhead$ pwd /home/kevint/WORKING_DIRECTORY/out/target/product/hammerheadkevint@kevintcl:hammerhead$ ls android-info.txt data previous_build_config.mk root boot.img fake_packages ramdisk.img symbols cache installed-files.txt ramdisk-recovery.img system cache.img kernel recovery system.img clean_steps.mk obj recovery.img userdata.img kevint@kevintcl:hammerhead$ 编译完了就刷机了哟：解锁Bootloader只有在Bootloader是unlock模式下才可能烧录定制的系统，Nexus5设备默认的Bootloader都是locked的，需要解锁。先把Nexus5关机，然后
同时按住音量的2个键和power键，进入fastbootmode，执行下面命令解锁：
$fastbootoem unlock （刷机完成后执行fastboot oem lock 加锁）
官方推荐在烧录系统前格式化 cache 和 userdate ，注意在执行下面命令前做好手机数据的备份：kevint@kevintcl:hammerhead-krt16m$
fastboot format cache erasing 'cache'... OKAY [ 0.646s] formatting 'cache' partition... Creating filesystem with parameters: Size: 734003200 Block size: 4096 Blocks per group: 32768 Inodes per group: 7472 Inode size: 256 Journal blocks: 2800 Label: Blocks: 179200 Block groups: 6 Reserved block group size: 47 Created filesystem with 11/44832 inodes and 5813/179200 blocks sending 'cache' (13348 KB)... writing 'cache'... OKAY [ 2.007s] finished. total time: 2.653s kevint@kevintcl:hammerhead-krt16m$ kevint@kevintcl:hammerhead-krt16m$
fastboot format userdataerasing 'userdata'...OKAY [ 12.327s]formatting 'userdata' partition...Creating filesystem with parameters: Size: 13725835264 Block size: 4096 Blocks per group: 32768 Inodes per group: 8144 Inode size: 256 Journal blocks: 32768 Label: Blocks: 3351034 Block groups: 103 Reserved block group size: 823Created filesystem with 11/838832 inodes and 93654/3351034 blockssending 'userdata' (137318 KB)...writing 'userdata'...OKAY [ 14.931s]finished. total time: 27.258skevint@kevintcl:hammerhead-krt16m$ .刷入Android4.4 适配的Bootloader和基带版本从官方提供的出厂镜像中可以找到合适的Bootloader和radio信息，如果不执行这步，查看“Settings->"Aboutphone”->"Basebandversion"为“unknown”，更简单的说，打不了电话....google factory image:
https://developers.google.com/android/nexus/images选择对应版本
"hammerhead" for Nexus 5 (GSM/LTE)
| Version | Download | MD5 Checksum | SHA-1 Checksum |
|---|
| 4.4 (KRT16M) | Link | 36aa82ab2d7d05ee144d18546565cd5f | bd9c39ded5dc0ac80c4e96d24db060a660266033 |
| 4.4.2 (KOT49H) | Link | fa3bdfbef24c25b48d4969e0925bc600 | 02006b9917ae3f470d29644023b7c843ec96aa03 |
| 4.4.3 (KTU84M) | Link | 34a201b32259aadcc8c4879e45c1575c | 53ff95bf3912814b745e65cab6bc111bde987537 |
| 4.4.4 (KTU84P) | Link | d450411b40a6e60884c8e419bd50db2b | 35ea0277bd6a8fc928b47256bfa97b2eed60746b |
| 4.4.4 Release 2 (For 2Degrees/NZ, Telstra/AUS and India ONLY) (KTU84Q) | Link | b079669398b128dfed4cab3d0471241f | ae4752935beebeeffdba4937c8a729bb57f87b32 |
| 5.0 (LRX21O) | Link | 761667f1ddaf4e38d4792136df4ab927 | 01315e08c7f282452b5eba0606dd5a2d5274edde |
| 5.0.1 (LRX22C) | Link | f769bb85b7a82c1b4f7cc88f0d42129d | 0f9eda1b8c801bec45f762c96121e7ae905976c0 |
| 5.1.0 (LMY47D) | Link | 021fa0ed4946e0c7e70e39da301e5a34 | 6c1ad81eb8b90b329da5ed534af6ef18dea9921c |
| 5.1.0 (LMY47I) | Link | d78c50bc06fe37a19536cbca0a17394a | df127988e25758e683d53df9767cc799ee113935 |
我下的是4.4(KRT16M)，下载文件解压后的文件信息如下：bootloader-hammerhead-HHZ11d.img (Nexus5 的bootloader镜像)flash-base.shflash-all.bat image-hammerhead-krt16m.zip (出厂镜像)flash-all.sh radio-hammerhead-M8974A-1.0.25.0.17.img (Nexus5的基带镜像)把bootloader和radio刷入Nexus5，我使用了自己的路径，注意要替换成你的路径：
kevint@kevintcl:hammerhead$ fastboot flash bootloader ~/nexus5/4-4-KRT16M/hammerhead-krt16m/bootloader-hammerhead-HHZ11d.img
刷好bootloader后重启进入bootloader用最新的bootloader进行烧录radio和编译好的rom:
kevint@kevintcl:hammerhead$ fastbootreboot-bootloader
刷入基带radio:
kevint@kevintcl:hammerhead$ fastbootflash radio ~/nexus5/4-4-KRT16M/hammerhead-krt16m/radio-hammerhead-M8974A-1.0.25.0.17.img
下面是具体步骤kevint@kevintcl:hammerhead$ which fastboot/home/kevint/WORKING_DIRECTORY/out/host/linux-x86/bin/fastboot （fastboot 是编译完源码生成的，路径WORKING_DIRECTORY/out/host/linux-x86/bin/fastboot ）kevint@kevintcl:hammerhead$
fastboot devices 检测手机是否链接好 04d6bfad010adbd0 fastboot kevint@kevintcl:hammerhead$
fastboot flash bootloader ~/nexus5/4-4-KRT16M/hammerhead-krt16m/bootloader-hammerhead-HHZ11d.img sending 'bootloader' (2506 KB)... OKAY [ 0.270s] writing 'bootloader'... OKAY [ 0.502s] finished. total time: 0.772s kevint@kevintcl:hammerhead$
fastboot reboot-bootloader rebooting into bootloader... OKAY [ 0.001s] finished. total time: 0.001s kevint@kevintcl:hammerhead$
fastboot flash radio ~/nexus5/4-4-KRT16M/hammerhead-krt16m/radio-hammerhead-M8974A-1.0.25.0.17.img sending 'radio' (42033 KB)... OKAY [ 1.627s] writing 'radio'... OKAY [ 2.901s] finished. total time: 4.529s kevint@kevintcl:hammerhead$ ls android-info.txt data previous_build_config.mk root boot.img fake_packages ramdisk.img symbols cache installed-files.txt ramdisk-recovery.img system cache.img kernel recovery system.img clean_steps.mk obj recovery.img userdata.img kevint@kevintcl:hammerhead$ fastboot reboot-bootloaderrebooting into bootloader... OKAY [ 0.001s] finished. total time: 0.001s
烧录到设备 (Nexus5)完整的Android 4.4 可以通过一行简单的命令刷入Nexus5，它在检测bootloader和radio版本和编译好的Android版本匹配后把boot、recovery、system文件分区烧录到设备中，命令里的“-w”参数是wipe，就是把所有的userdata格式化，如果有要保留的数据注意备份：kevint@kevintcl:hammerhead$
fastboot -w flashall-------------------------------------------- Bootloader Version...: HHZ11d Baseband Version.....: M8974A-1.0.25.0.17 Serial Number........: 04d6bfad010adbd0 -------------------------------------------- checking product... OKAY [ 0.100s] sending 'boot' (8620 KB)... OKAY [ 0.515s] writing ' boot' ... OKAY [ 0.760s] sending 'recovery' (9202 KB)... OKAY [ 0.570s] writing 'recovery'... OKAY [ 0.782s] erasing 'system'... OKAY [ 1.018s] sending 'system' (294108 KB)... OKAY [ 10.932s] writing 'system'... OKAY [ 21.399s] erasing 'userdata'... OKAY [ 7.391s] formatting 'userdata' partition... Creating filesystem with parameters: Size: 13725835264 Block size: 4096 Blocks per group: 32768 Inodes per group: 8144 Inode size: 256 Journal blocks: 32768 Label: Blocks: 3351034 Block groups: 103 Reserved block group size: 823 Created filesystem with 11/838832 inodes and 93654/3351034 blocks sending 'userdata' (137318 KB)... writing 'userdata'... OKAY [ 14.700s] erasing 'cache'... OKAY [ 0.554s] formatting 'cache' partition... Creating filesystem with parameters: Size: 734003200 Block size: 4096 Blocks per group: 32768 Inodes per group: 7472 Inode size: 256 Journal blocks: 2800 Label: Blocks: 179200 Block groups: 6 Reserved block group size: 47 Created filesystem with 11/44832 inodes and 5813/179200 blocks sending 'cache' (13348 KB)... writing 'cache'... OKAY [ 1.995s] rebooting... finished. total time: 61.249s kevint@kevintcl:hammerhead$ 最后机子自己重启了。
