From 3ccc448bdd712f78b6ed1a6ced76ae0e8597ee85 Mon Sep 17 00:00:00 2001
From: Linus Heckemann <git@sphalerite.org>
Date: Wed, 6 Jan 2021 23:29:02 +0100
Subject: [PATCH] emmc-image: faster build

---
 emmc-image.nix | 17 +++++------------
 1 file changed, 5 insertions(+), 12 deletions(-)

diff --git a/emmc-image.nix b/emmc-image.nix
index f94de2d..a2f0745 100644
--- a/emmc-image.nix
+++ b/emmc-image.nix
@@ -37,13 +37,8 @@
 
       buildCommand = ''
         mkdir -p $out/nix-support $out/sd-image
-        export img=$out/sd-image/${config.sdImage.imageName}
+        export img=${config.sdImage.imageName}
         echo "${pkgs.stdenv.buildPlatform.system}" > $out/nix-support/system
-        if test -n "$compressImage"; then
-          echo "file sd-image $img.bz2" >> $out/nix-support/hydra-build-products
-        else
-          echo "file sd-image $img" >> $out/nix-support/hydra-build-products
-        fi
         echo "Decompressing rootfs image"
         zstd -d --no-progress "${rootfsImage}" -o ./root-fs.img
 
@@ -66,19 +61,17 @@
 
         # Copy the rootfs into the SD image
         eval $(partx $img -o START,SECTORS --nr 3 --pairs)
-        dd conv=notrunc if=./root-fs.img of=$img seek=$START count=$SECTORS
+        dd conv=notrunc if=./root-fs.img of=$img seek=$((START/64)) count=$((SECTORS/64)) bs=$((512*64))
 
         # Copy u-boot into the SD image
         eval $(partx $img -o START,SECTORS --nr 2 --pairs)
-        dd conv=notrunc if=${pkgs.ubootHelios64}/u-boot.itb of=$img seek=$START count=$SECTORS
+        dd conv=notrunc if=${pkgs.ubootHelios64}/u-boot.itb of=$img seek=$((START/64)) count=$((SECTORS/64)) bs=$((512*64))
 
         # Copy bootloader into the SD image
         eval $(partx $img -o START,SECTORS --nr 1 --pairs)
-        dd conv=notrunc if=${pkgs.ubootHelios64}/idbloader.img of=$img seek=$START count=$SECTORS
+        dd conv=notrunc if=${pkgs.ubootHelios64}/idbloader.img of=$img seek=$((START/64)) count=$((SECTORS/64)) bs=$((512*64))
 
-        if test -n "$compressImage"; then
-            zstd -v --no-progress $img
-        fi
+        zstd -v --no-progress $img -o $out/sd-image/${config.sdImage.imageName}.zstd
       '';
     }) {};
 }