Workflow: use buildroot download cache

.github/workflows/build.yml

@@ -208,6 +208,9 @@ jobs:
         run: |
           echo "8.8.8.8 invisible-mirror.net" | sudo tee -a /etc/hosts
           echo "8.8.8.8 distfiles.dereferenced.org" | sudo tee -a /etc/hosts
+          make prepare
+          git clone https://github.com/openipc/br-cache
+          ln -s ${GITHUB_WORKSPACE}/br-cache $(ls -d output/buildroot-*)/dl
           make BOARD=${{matrix.platform}}_${{matrix.release}} br-source
           echo - Download time: $(date -d @${SECONDS} +%M:%S)
 

Makefile

@@ -1,6 +1,6 @@
 BR_VER = 2023.02.2
 BR_MAKE = $(MAKE) -C $(TARGET)/buildroot-$(BR_VER) BR2_EXTERNAL=$(PWD)/general O=$(TARGET)
-BR_LINK = https://github.com/buildroot/buildroot/archive/refs/tags
+BR_LINK = https://github.com/buildroot/buildroot/archive
 BR_FILE = /tmp/buildroot-$(BR_VER).tar.gz
 TARGET ?= $(PWD)/output
 
@@ -44,12 +44,14 @@ build: defconfig
 br-%: defconfig
 	@$(BR_MAKE) $(subst br-,,$@)
 
-defconfig:
+defconfig: prepare
 	@echo --- $(or $(CONFIG),$(error variable BOARD is not found))
+	@$(BR_MAKE) BR2_DEFCONFIG=$(PWD)/$(CONFIG) defconfig
+
+prepare:
 	@if test ! -e $(TARGET)/buildroot-$(BR_VER); then \
 		wget -c -q $(BR_LINK)/$(BR_VER).tar.gz -O $(BR_FILE); \
 		mkdir -p $(TARGET); tar -xf $(BR_FILE) -C $(TARGET); fi
-	@$(BR_MAKE) BR2_DEFCONFIG=$(PWD)/$(CONFIG) defconfig
 
 toolname:
 	@general/scripts/show_toolchains.sh $(CONFIG)