libbinder: update Trusty README
Bug: 224644083
Test: N/A
Change-Id: Ic4716ad06a834d1148e00efd11ba0ea6bcc12b26
diff --git a/libs/binder/trusty/README.md b/libs/binder/trusty/README.md
index 1a273aa..8a60af8 100644
--- a/libs/binder/trusty/README.md
+++ b/libs/binder/trusty/README.md
@@ -1,39 +1,45 @@
# Binder for Trusty
This is the Trusty port of the libbinder library.
-To build it, take the following steps:
-
-* Check out copies of the Trusty and AOSP repositories.
-* Apply the patches from the `trusty_binder` topic on both repositories.
-* Build Trusty normally using `build.py`.
-* Run the sample AIDL test for Trusty:
- ```shell
- $ ./build-root/.../run --headless --boot-test com.android.trusty.aidl.test
- ```
-
-To run the Android-Trusty IPC test, do the following:
-
-* Build AOSP for the `qemu_trusty_arm64-userdebug` target:
- ```shell
- $ lunch qemu_trusty_arm64-userdebug
- $ m
- ```
-* In the Trusty directory, run the emulator with the newly built Android:
- ```shell
- $ ./build-root/.../run --android /path/to/aosp
- ```
-* Using either `adb` or the shell inside the emulator itself, run the Trusty
- Binder test as root:
- ```shell
- # /data/nativetest64/vendor/trusty_binder_test/trusty_binder_test
- ```
-
-## Running the AIDL compiler
-For now, you will need to run the AIDL compiler manually to generate the C++
-source code for Trusty clients and services. The general syntax is:
+To build it, first you will need a checkout of the Trusty tree:
```shell
-$ aidl --lang=cpp -o <output directory> -h <output header directory> <AIDL files...>
+$ mkdir /path/to/trusty
+$ cd /path/to/trusty
+$ repo init -u https://android.googlesource.com/trusty/manifest -b master
+$ repo sync -j$(nproc) -c --no-tags
```
-The compiler will emit some `.cpp` files in the output directory and their
-corresponding `.h` files in the header directory.
+After the checkout is complete, you can use the `build.py` script for both
+building and testing Trusty. For a quick build without any tests, run:
+```shell
+$ ./trusty/vendor/google/aosp/scripts/build.py generic-arm64-test-debug
+```
+This will build the smaller `generic-arm64-test-debug` project which
+does not run any tests.
+
+The qemu-generic-arm64-test-debug` project includes the QEMU emulator and
+a full Trusty test suite, including a set of libbinder tests.
+To run the latter, use the command:
+```shell
+$ ./trusty/vendor/google/aosp/scripts/build.py \
+ --test "boot-test:com.android.trusty.binder.test" \
+ qemu-generic-arm64-test-debug
+```
+
+## Building AIDL files on Trusty
+To compile AIDL interfaces into Trusty libraries, include the `make/aidl.mk`
+in your `rules.mk` file, e.g.:
+```
+LOCAL_DIR := $(GET_LOCAL_DIR)
+
+MODULE := $(LOCAL_DIR)
+
+MODULE_AIDLS := \
+ $(LOCAL_DIR)/IFoo.aidl \
+
+include make/aidl.mk
+```
+
+## Examples
+The Trusty tree contains some sample test apps at
+`trusty/user/app/sample/binder-test`.