clearfog: fancy flashing
There's no need to use emergency.target anymore, the `run usbboot` (or
its longer equivalent if we're in Marvell's factory U-Boot) will perform
the flashing automatically.
It's a bit complex because one has to wait for /dev/sda1 to appear
first. That needs udev to be running. Then one has to mount the image.
In the end I decided to go for a unit generator because it is not clear
whether the actual .device unit is just `dev-sda1.unit` or something
much more interesting like `sys-devices-platform-soc-soc:internal\x2dregs-f10f8000.usb3-usb2-2\x2d1-2\x2d1:1.0-host4-target4:0:0-4:0:0:0-block-sda-sda1.device`.
Change-Id: I1d1bc64e453c94c568cb84bc52f61dafa2a3b15d
diff --git a/board/czechlight/clearfog/usb-boot.scr.txt b/board/czechlight/clearfog/usb-boot.scr.txt
index 0227a74..c3ca6e8 100644
--- a/board/czechlight/clearfog/usb-boot.scr.txt
+++ b/board/czechlight/clearfog/usb-boot.scr.txt
@@ -1,4 +1,4 @@
-setenv bootargs systemd.unit=emergency.target
+setenv bootargs systemd.unit=usb-flash.service
fatload usb 0:1 ${kernel_addr_r} zImage
fatload usb 0:1 ${fdt_addr_r} czechlight-clearfog.dtb
fatload usb 0:1 ${ramdisk_addr_r} rootfs.cpio.uboot