[timvideos#387] Temporarily switch to a built-in DTB file on mor1kx

This is to be reverted after the support for an external DTB file
is brought back to LiteX.

Makefile

@@ -406,14 +406,14 @@ tftp: $(FIRMWARE_FILEBASE).bin
 
 ifeq ($(FIRMWARE),linux)
 	cp $(FIRMWARE_FILEBASE).bin $(TFTPD_DIR)/Image
-	cp $(FIRMWARE_DIR)/$(ROOTFS_FILE) $(TFTPD_DIR)/rootfs.cpio
 	cp $(FIRMWARE_DIR)/boot.json $(TFTPD_DIR)
 ifeq ($(CPU),vexriscv)
 	cp $(FIRMWARE_DIR)/rv32.dtb $(TFTPD_DIR)
 	cp $(TARGET_BUILD_DIR)/emulator/emulator.bin $(TFTPD_DIR)
+	cp $(FIRMWARE_DIR)/$(ROOTFS_FILE) $(TFTPD_DIR)/rootfs.cpio
 endif
 ifeq ($(CPU),mor1kx)
-	cp $(FIRMWARE_DIR)/mor1kx.dtb $(TFTPD_DIR)
+        # ATM nothing, DTB in the future
 endif
 else
 	cp $(FIRMWARE_FILEBASE).bin $(TFTPD_DIR)/boot.bin

scripts/build-linux.sh

@@ -54,7 +54,6 @@ fi
 
 LINUX_REMOTE="${LINUX_REMOTE:-https://github.com/litex-hub/linux.git}"
 LINUX_REMOTE_NAME=litex-hub-linux
-LINUX_BRANCH=${LINUX_BRANCH:-litex_buildenv}
 
 RESOURCES_LOCATION="https://dl.antmicro.com/projects/renode/litex-buildenv/"
 
@@ -64,7 +63,9 @@ if [ ${CPU} = mor1kx ]; then
 	DTB=mor1kx.dtb
 	ROOTFS_MD5="c9ef89b45b0d2c34d14978a21f2863bd"
 	DTB_MD5="0271bc8f63f2d928dc9536ac31a2c6b9"
+	LINUX_BRANCH=${LINUX_BRANCH:-litex_buildenv-mor1kx}
 elif [ ${CPU} = vexriscv ]; then
+	LINUX_BRANCH=${LINUX_BRANCH:-litex_buildenv}
 	export ARCH=riscv
 	ROOTFS=riscv32-rootfs.cpio
 	DTB=rv32.dtb
@@ -222,11 +223,11 @@ LLV_SRC="$TOP_DIR/third_party/linux-on-litex-vexriscv"
 	fetch_file $RESOURCES_LOCATION/$DTB_MD5-$DTB       $DTB_MD5    $TARGET_LINUX_BUILD_DIR/$DTB
 
 	if [ ${CPU} = mor1kx ]; then
+    	        cp $TARGET_LINUX_BUILD_DIR/$DTB arch/openrisc/boot/dts
 		KERNEL_BINARY=vmlinux.bin
 
         	cat << EOF > $TARGET_LINUX_BUILD_DIR/boot.json
 {
-    "mor1kx.dtb":   "0x01000000",
     "Image":        "0x00000000"
 }
 EOF