From fdbecb02b65fd8bf3a871e5a99b83bcdf6c02af2 Mon Sep 17 00:00:00 2001
From: Samuel Dionne-Riel <samuel@dionne-riel.com>
Date: Mon, 6 Jan 2020 15:21:02 -0500
Subject: [PATCH] Set this up using a proper overlay

---
 README.md   |  2 +-
 default.nix | 16 +++++++++-------
 overlay.nix | 10 ++++++++++
 3 files changed, 20 insertions(+), 8 deletions(-)
 create mode 100644 overlay.nix

diff --git a/README.md b/README.md
index 7a09bda..14313eb 100644
--- a/README.md
+++ b/README.md
@@ -5,7 +5,7 @@ WIP stuff to get started on the pinebook pro.
 Assuming `/dev/mmcblk0` is an SD card.
 
 ```
-$ nix-build -A u-boot
+$ nix-build -A pkgs.u-boot-pinebookpro
 $ lsblk /dev/mmcblk0 && sudo dd if=result/idbloader.img of=/dev/mmcblk0 bs=512 seek=64 oflag=direct,sync && sudo dd if=result/u-boot.itb of=/dev/mmcblk0 bs=512 seek=16384 oflag=direct,sync
 ```
 
diff --git a/default.nix b/default.nix
index 087a092..47cc262 100644
--- a/default.nix
+++ b/default.nix
@@ -1,15 +1,17 @@
 {
-  pkgs' ? import <nixpkgs> {}
+  pkgs ? import (builtins.fetchTarball "channel:nixos-19.09") {
+    overlays = [
+      (import ./overlay.nix)
+    ];
+  }
 }:
 
 let
-  pkgs = if builtins.currentSystem == "aarch64-linux"
-    then pkgs'
-    else pkgs'.pkgsCross.aarch64-multiplatform
+  pkgs' = if builtins.currentSystem == "aarch64-linux"
+    then pkgs
+    else pkgs.pkgsCross.aarch64-multiplatform
   ;
-
-  inherit (pkgs) callPackage;
 in
 {
-  u-boot = callPackage ./u-boot {};
+  pkgs = pkgs';
 }
diff --git a/overlay.nix b/overlay.nix
new file mode 100644
index 0000000..524d8e2
--- /dev/null
+++ b/overlay.nix
@@ -0,0 +1,10 @@
+final: super:
+
+let
+  inherit (final) callPackage;
+in
+{
+  # Alternative BSP u-boot, with nvme support if desired
+  #   * https://gitlab.manjaro.org/manjaro-arm/packages/core/uboot-pinebookpro
+  u-boot-pinebookpro = callPackage ./u-boot {};
+}