docs: Document building pvmfw.img from source in U
Add instructions for building pvmfw.img from source.
Bug: 253397262
Test: -
Change-Id: I9a3561d3fee456a7a0e5adcde2da4b63f65a7fb1
diff --git a/docs/getting_started/index.md b/docs/getting_started/index.md
index a354339..8a1e6dd 100644
--- a/docs/getting_started/index.md
+++ b/docs/getting_started/index.md
@@ -71,6 +71,14 @@
Android 13 followed by the manual steps above for flashing the `other` slot
should be used as a last resort.
+Starting in Android 14, `pvmfw.img` can be built using the Android Build system:
+```
+lunch <target> # where PRODUCT_BUILD_PVMFW_IMAGE=true
+m pvmfwimage # partition image under ${ANDROID_PRODUCT_OUT}/pvmfw.img
+```
+Note that the result is not intended to be used in Android 13 as not
+backward-compatibility is guaranteed.
+
## Running demo app
The instruction is [here](../../demo/README.md).