start_file doesn't work inside config.txt filters
ali1234 opened this issue · comments
Example config.txt:
[all]
gpio=5=ip,pu
[gpio5=0]
start_file=msd.elf
[gpio5=1]
start_file=start.elf
Expected result: Pi should boot msd.elf if gpio5 is externally pulled low.
Actual result: Pi boots whatever start_file is last in the file, regardless of filters.
Filtering is only supported by start.elf, not bootcode.bin (which is much simpler).
So, filtering won't work on config.txt options handled by bootcode.bin. e.g.
gpu_mem
gpu_mem_256
gpu_mem_512
gpu_mem_1024
total_mem
require_total_mem
startx
start_x
start_debug
boot_partition
legacy_mapping
bootcode_delay
force_pvt
uart_2ndstage
start_file
fixup_file
I've had a go at adding gpio filters to bootcode.bin. Can you try this bootcode.bin?
https://drive.google.com/uc?id=19LE7WHmbBZgxEowi48Q8ilOVeg0nQrm7&export=download
I tested this using rpi-ramdisk. The msd/start.elf is renamed to msd.elf and added alongside all the usual firmware files. Then my config.txt is similar to the above but loading start_x.elf and my initrd in the normal case:
gpio=5=ip,pu
[gpio5=0]
start_file=msd.elf
[gpio5=1]
start_x=1
initramfs initrd
I tested this with rpiboot on a Pi Zero and copying everything to the SD card on a 3A+. In both cases it worked - the normal firmware would boot unless gpio 5 is pulled low, and then the device goes to MSD mode where I can update the files on the SD card.
This is a HUGE time saver when I am testing initrds as I no longer need to put the SD card into a PC to reflash after every build. For Zero I could use rpiboot and for the 3B I could use PXE booting. But the 3A+ current can't do either of those so this is a great help.
Are there any particular corner cases you would like me to test?
@popcornmix Did this get merged? OK to close?
Yes, this is in rpi-update bootcode.bin (pushed 22 days ago).
Closing this issue as questions answered/issue resolved.