README.md

Breadbee dev

This is a janky environment to manage building u-boot and kernel images so you can quickly hack on u-boot or the kernel and test your work.

Getting started

To get started you need to checkout this repo and then populate it with the u-boot, kernel and buildroot sources by running the bootstrap target:

make bootstrap

Once this is complete any of the targets below should build. Note that the first build will take a long time as the toolchain and rootfs build will be triggered. Subsequent builds will reuse the toolchain and rootfs and will be much faster.

Targets

rtk

This is a special target that is not for the breadbee at all. Instead this is for development using a mercury5 device. The m5 IPL looks for a file called rtk (real time kernel?) on the first FAT partition, loads it to DRAM and jumps into it. We can exploit this to load u-boot into DRAM and start it.

This can be useful because the infinity3 (breadbee Soc) and mercury5 are very similar but the mercury5 supports booting u-boot from SD card so it's a lot easier to work with than flashing the SPI NOR each time.

make rtk

spl

This builds the u-boot SPL, pads it and fixes up the image checksum so it can be loaded from the IPL.

make spl

kernel_m5.fit

This builds a kernel FIT image without the breadbee overlays but with the breadbee rescue initramfs. This is mainly for testing on mercury5 where actually writing the rootfs to the SPI NOR would destroy the existing firmware that is still useful for making sure the screen etc are still working.

make kernel_m5.fit

kernel_breadbee.fit

This builds a kernel FIT image with the breadbee overlays and without any built in initramfs. This is mainly for TFTP booting on a breadbee to test kernel changes with the rootfs already being on SPI NOR.

make kernel_breadbee.fit

kernel_ssd201htv2

This builds a kernel with an appended DTB for the ssd201htv2 with the vendor u-boot

mw 0x16002000 0x1e0; setenv serverip 192.168.3.235; setenv loadaddr 0x22000000; dhcp kernel_ssd201htv2; go ${loadaddr}

kernel_gw302

This builds a kernel with an appended DTB for the gw302 with the vendor u-boot

mw 0x16002000 0x1e0; setenv serverip 192.168.3.235; setenv loadaddr 0x22000000; dhcp kernel_gw302; go ${loadaddr}

kernel_ssd20x.fit

This builds a generic kernel for ssd20xd machines with an updated u-boot

setenv serverip 192.168.3.235; setenv loadaddr 0x22000000; dhcp dev_kernel_ssd20xd.fit; bootm ${loadaddr}

For gw302:

With the built in initramfs for debugging

setenv serverip 192.168.3.235; setenv loadaddr 0x22000000; dhcp dev_kernel_ssd20xd.fit; bootm ${loadaddr}#gw302

Without the built in initramfs, use NAND partitions.

setenv serverip 192.168.3.235; setenv loadaddr 0x22000000; dhcp dev_kernel_ssd20xd.fit; bootm ${loadaddr}#gw302_nord 

setenv serverip 192.168.3.235; setenv loadaddr 0x22000000; dhcp dev_kernel_ssd20xd.fit; bootm ${loadaddr}#som2d01_ssd202

kernel_mcf50

This builds a kernel with an appended DTB for the mcf50 with the vendor u-boot

mw 0x16002000 0x1e0; setenv serverip 192.168.3.235; setenv loadaddr 0x22000000; dhcp kernel_mcf50; go ${loadaddr}

Booting up the outputs

Booting the dev kernel over TFTP

setenv serverip 192.168.3.235; setenv loadaddr 0x22000000; dhcp dev_kernel_breadbee.fit; bootm ${loadaddr}"#"${bb_boardtype}${bb_config}

Booting the vendor kernel over TFTP

setenv serverip 192.168.3.235; setenv loadaddr 0x22000000; dhcp dev_vendor.fit; bootm ${loadaddr}

Booting the dev kernel and override the configured overlays

setenv serverip 192.168.3.1; setenv loadaddr 0x22000000; dhcp kernel.fit.breadbee; bootm ${loadaddr}"#breadbee#sdio_sd"

booting the kernel from sd card

mercury5 midrive d06

fatload mmc 0:1 $loadaddr kernel.fit; bootm $loadaddr#midrived06

mercury5 midrive d08

fatload mmc 0:1 $loadaddr kernel.fit; bootm $loadaddr#midrive08

mercury5 mirror cam

fatload mmc 0:1 $loadaddr kernel.fit; bootm $loadaddr#mirrorcam

Chain loading u-boot from another u-boot

setenv serverip 192.168.3.235; setenv loadaddr 0x22000000; dhcp generic-ipl;
cp.b $loadaddr 0xa0000000 0xbb80
go 0xa0000000

Replacing u-boot on the breadbee

Via ethernet

setenv serverip 192.168.3.235; if dhcp dev_u-boot_breadbee.img; then; sf probe; sf erase 0x20000 0x50000; sf write 0x22000000 0x20000 0x50000; fi

Via uart

if loady ${loadaddr} 460800; then; sf probe; sf erase 0x20000 0x50000; sf write 0x22000000 0x20000 0x50000; fi

if loady ${loadaddr} 460800; then; sf probe; sf erase 0x10000 0x10000; sf write 0x22000000 0x10000 0x10000; fi