Minor elaborations on docs, squash gitignores

.gitignore

@@ -1,3 +1,5 @@
 *.idea
+**/*.rs.bk
+*.swp
 target
 Cargo.lock

README.md

@@ -1,14 +1,21 @@
 # libsel4-sys
 
-Builds the sel4 kernel and generates bindings around it,
+Builds the sel4 kernel and generates Rust bindings around it,
 as configured by a fel4 manifest.
 
+This library provides thin Rust bindings around the [seL4 codebase](https://github.com/seL4/seL4);
+more idiomatic Rust wrappers for the enclosed functionality will be supplied in other crates.
+
+Intended for use in projects managed by
+[cargo fel4](https://github.com/PolySync/cargo-fel4), see that repository
+for introductory materials.
+
 ## Project Layout
 
 ```
 libsel4-sys/
 ├── Cargo.toml
-├── build.rs                <-- Pulls in fel4 toml for CMake configuration
+├── build.rs                <-- Configures CMake with fel4 manifest data, runs CMake and bindgen
 ├── CMakeLists.txt
 ├── deps                    <-- submodules to seL4 repositories
 │   ├── musllibc
@@ -17,29 +24,23 @@ libsel4-sys/
 │   ├── seL4_tools
 │   └── util_libs
 ├── package
-│   └── CMakeLists.txt      <-- custom CMake script to build seL4 artifacts
+│   └── CMakeLists.txt      <-- custom CMake script wrapper to build seL4 artifacts
 ├── README.md
 ├── res
 │   └── bindgen_wrapper.h
 ├── src
-│   └── lib.rs
+│   └── lib.rs              <-- thin wrapper around the generated bindings
 └── Xargo.toml
 ```
 
-## Down-stream Configuration
-
-Down-stream consumers can specify a toml file that contains the CMake configuration
-tables via the `FEL4_MANIFEST_PATH` variable.
-
 ## Building
 
 Don't forget to run `git submodule update --init` to pull in the seL4 related dependencies
-before you start hacking.
+to the local filesystem before attempting a build.
 
 This project is intended to be built in the context of the `cargo fel4` command, which manages
 the piping of key environment variables relevant to the downstream project.
 
-
 Builds require that the `FEL4_MANIFEST_PATH` environment variable is set and
 includes a path that points to a valid fel4.toml file, as specified by the `fel4-config`
 crate.
@@ -53,6 +54,11 @@ RUST_TARGET_PATH=$PWD/test_configs FEL4_MANIFEST_PATH=$PWD/test_configs/fel4.tom
 
 ## Output Artifacts
 
+The generated bindings should be treated as relatively ephemeral and dynamic compared
+to most Rust libraries. The output is context-specific to the target (e.g. "arm-sel4-fel4")
+and the set of configuration
+flags derived from the input fel4 manifest file.
+
 If environment variable `FEL4_ARTIFACT_PATH` is set, the kernel and simulation script
 will be copied into the directory specified by the variable.
 

test_configs/README.md

@@ -1,6 +1,10 @@
 ## fel4.toml
 An example fel4 manifest that could be used to configure
-the build of libsel4-sys
+the build of libsel4-sys. See the [fel4-config repository](https://github.com/PolySync/fel4-config)
+for more information about the fel4 manifest format.
 
 ## feL4-targets JSON files
 Example Rust target specifications for feL4.
+Note that these are for reference only, and the primary source of truth
+for supported target specifications can be found in the
+[cargo-fel4 repository](https://github.com/PolySync/cargo-fel4).