VINTF - compatibility matrix

Compatibility Matrix (CM)

1. 系统共需要3个compatibility matrix文件

  • System Compatibility Matrix (hardware/interfaces/compatibility_matrices/Android.mk), 下文简称scm
  • Device Compatibility Matrix (system/libhidl/vintfdata/Android.mk), 下文简称vcm
  • Product Compatibility Matrix (hardware/interfaces/compatibility_matrices/Android.mk), 下文简称pcm

其中scm, vcm是必然要生成的，而pcm则只有在定义了DEVICE_PRODUCT_COMPATIBILITY_MATRIX_FILE之后才会生成。

scm:

该文件生成比较繁琐，需要多个步骤
首先需要生成CM的check文件：
-i hardware/interfaces/compatibility_matrices/manifest.empty.xml -o manifest.check.xml
需要生成6个实际文件

compatibility_matrix.1.xml
compatibility_matrix.2.xml
compatibility_matrix.3.xml
compatibility_matrix.4.xml
compatibility_matrix.legacy.xml
compatibility_matrix.device.xml （FCM）
前5个文件定义于hardware/interfaces/compatibility_matrices/Android.bp, 从同文件夹的同名文件加上多个版本的kernel config生成(目前看到对于Oreo是3.18, 4.4, 4.9 等, 对于Q是4.9, 4.14, 4.19等)
第6个文件FCM, 从DEVICE_FRAMEWORK_COMPATIBILITY_MATRIX_FILE或者compatibility_matrix.empty.xml生成

vcm:

额外需要的变量 REQUIRED_VNDK_VERSION, BOARD_SYSTEMSDK_VERSIONS, 生成的CM带有VDNK版本号和SYSTEMSDK版本号

pcm:

强制check文件为空, 参数增加”-c hardware/interfaces/compatibility_matrices/manifest.empty.xml”

2. 图表总结

+--------+-----------------------------------------+-------------------------------+--------------------------------------------+
|Targets | Makefile Commands                       |output                         | 源文件(input files) |                      |
+--------+-----------------------------------------+-------------------------------+--------------------------------------------+
|scm(fcm)| make                                    |/system/etc/vintf/             | compatibility_matrix.empty.xml             |
|        |framework_compatibility_matrix.device.xml|compatibility_matrix.device.xml|  or                                        |
|        |                                         |                               | DEVICE_FRAMEWORK_COMPATIBILITY_MATRIX_FILE |
+--------+-----------------------------------------+-------------------------------+--------------------------------------------+
|scm(all)| make system_compatibility_matrix.xml    | scm + other 5 files           | 同名源文件 + 多个版本的kernel config       |
+--------+-----------------------------------------+-------------------------------+--------------------------------------------+
|vcm     | make device_compatibility_matrix.xml    |/vendor/etc/vintf/             | device_compatibility_matrix.default.xml    |
|        |                                         |compatibility_matrix.xml       |  or DEVICE_MATRIX_FILE                     |
+--------+-----------------------------------------+-------------------------------+--------------------------------------------+
|pcm     | make product_compatibility_matrix.xml   |/product/etc/vintf/            | DEVICE_PRODUCT_COMPATIBILITY_MATRIX_FILE   |
|        |                                         |compatibility_matrix.xml       |                                            |
+--------+-----------------------------------------+-------------------------------+--------------------------------------------+