android system setup and building (2)

Configuring a New Product

http://source.android.com/porting/build_new_device.html

Detailed Instructions

    下面步骤描述怎样为一个新的移动设备及产品使用makefiles配置Android运行系统。

 1.在//vendor/目录下创建一个公司目录.

mkdir vendor/<company_name>

2.在上面创建的公司目录下（beneath）创建产品（products）目录

 mkdir vendor/<company_name>/products/

3.创建特定产品的makefile。命名为vendor/<company_name>/products/<first_product_name>.mk。这个文件至少要包含如下代码：

  $(call inherit-product, $(SRC_TARGET_DIR)/product/generic.mk)
  #
  # Overrides
  PRODUCT_NAME := <first_product_name>
  PRODUCT_DEVICE := <board_name>

4.另外一些特定产品的变量定义可以添加到这个产品定义(Product Definition：下面有详细说明)文件(3中说的)。

5.在products目录，创建一个AndroidProducts.mk文件，这个文件用来指定(and is responsible for finding)一个特定的产品make 文件（也就是3中的文件）

  #
  # This file should set PRODUCT_MAKEFILES to a list of product makefiles
  # to expose to the build system.  LOCAL_DIR will already be set to
  # the directory containing this file. 
  #
  # This file may not rely on the value of any variable other than
  # LOCAL_DIR; do not use any conditionals, and do not look up the
  # value of any variable that isn't set in this file or in a file that
  # it includes.
  #
  
  PRODUCT_MAKEFILES := \
    $(LOCAL_DIR)/first_product_name.mk \

6.在公司名目录下创建一个特定板级目录，此目录名必须与3中特定产品的makefile 中PRODUCTV_DEVICE变量值<board_name>相同。这个目录下将包括一个makefile文件会被用到此板的产品使用。

 mkdir vendor/<company_name>/<board_name>

7.在上面(vendor/<company_name>/<board_name>)的目录下创建BoardConfig.mk文件：

  # These definitions override the defaults in config/config.make for <board_name>
  #
  # TARGET_NO_BOOTLOADER := false
  #
  TARGET_USE_GENERIC_AUDIO := true

8.如果你想更改系统属性(properties)，就在<board_name>目录（6中建立的目录）下创建system.prop文件。

  # system.prop for 
  # This overrides settings in the products/generic/system.prop file
  #
  # rild.libpath=/system/lib/libreference-ril.so
  # rild.libargs=-d /dev/ttyS0

9.在products/AndroidProducts.mk 文件中添加一个<second_product_name>.mk指针

  PRODUCT_MAKEFILES := \
    $(LOCAL_DIR)/first_product_name.mk \
    $(LOCAL_DIR)/second_product_name.mk

10.在vendor/<company_name>/<board_name>目录下必须创建一个Android.mk文件，此文件至少应该包含如下内容：

  # make file for new hardware  from 
  #
  LOCAL_PATH := $(call my-dir)
  #
  # this is here to use the pre-built kernel
  ifeq ($(TARGET_PREBUILT_KERNEL),)
  TARGET_PREBUILT_KERNEL := $(LOCAL_PATH)/kernel
  endif
  #
  file := $(INSTALLED_KERNEL_TARGET)
  ALL_PREBUILT += $(file)
  $(file): $(TARGET_PREBUILT_KERNEL) | $(ACP)
        $(transform-prebuilt-to-target)
  #
  # no boot loader, so we don't need any of that stuff..  
  #
  LOCAL_PATH := vendor/<company_name>/<board_name>
  #
  include $(CLEAR_VARS)
  #
  # include more board specific stuff here? Such as Audio parameters.      
  #

11.在同样的板上创建第二个产品，这第二个特定产品的make file文件命名为vendor/company_name/products/<second_product_name>.mk 包括如下内容：

  $(call inherit-product, $(SRC_TARGET_DIR)/product/generic.mk)
  #
  # Overrides
  PRODUCT_NAME := <second_product_name>
  PRODUCT_DEVICE := <board_name>

这样你就有两个产品，也就是与<company_name>相关的被命名为<first_product_name>和<second_product_name>。可执行如下命令来验证产品已经被很好的配置（以<first_product_name>为例）：

.build/envsetup.sh
make PRODUCT-<first_product_name>-user

 然后就会在/out/target/product/<board_name>目录下生成新编译出的二进制文件

New Product File Tree

• <company_name>
• <board_name>
• Android.mk
• product_config.mk
• system.prop
• products
• AndroidProducts.mk
• <first_product_name>.mk
• <second_product_name>.mk

Product Definition Files

 产品特定的变量被定义在产品说明文件(definition files)中。产品说明文件可以继承自其它的产品说明文件。这样将便于管理(thus reducing the need to copy and simplifying maintenance)。

 产品说明文件中可以包含如下变量：

Parameter	Description	Example
PRODUCT_NAME	End-user-visible name for the overall product. Appears in the "About the phone" info.
PRODUCT_MODEL	End-user-visible name for the end product
PRODUCT_LOCALES	A space-separated list of two-letter language code, two-letter country code pairs that describe several settings for the user, such as the UI language and time, date and currency formatting. The first locale listed in PRODUCT_LOCALES is is used if the locale has never been set before.	en_GB de_DE es_ES fr_CA
PRODUCT_PACKAGES	Lists the APKs to install.	Calendar Contacts
PRODUCT_DEVICE	Name of the industrial design	dream
PRODUCT_MANUFACTURER	Name of the manufacturer	acme
PRODUCT_BRAND	The brand (e.g., carrier) the software is customized for, if any
PRODUCT_PROPERTY_OVERRIDES	List of property assignments in the format "key=value"
PRODUCT_COPY_FILES	List of words like source_path:destination_path. The file at the source path should be copied to the destination path when building this product. The rules for the copy steps are defined in config/Makefile
PRODUCT_OTA_PUBLIC_KEYS	List of OTA public keys for the product
PRODUCT_POLICY	Indicate which policy this product should use
PRODUCT_PACKAGE_OVERLAYS	Indicate whether to use default resources or add any product specific overlays	vendor/acme/overlay
PRODUCT_CONTRIBUTORS_FILE	HTML file containing the contributors to the project.
PRODUCT_TAGS	list of space-separated words for a given product

典型产品说明文件如下：

$(call inherit-product, build/target/product/generic.mk)

#Overrides
PRODUCT_NAME := MyDevice
PRODUCT_MANUFACTUER := acme
PRODUCT_BRAND := acme_us
PRODUCT_LOCALES := en_GB es_ES fr_FR
PRODUCT_PACKAGE_OVERLAYS := vendor/acme/overlay

 

 。。。。