Josh, My perpetual goal for PSAS is to get a new (2.6.31) Linux kernel installed on it, with dave and kay's userspace code to talk to an lpcusb board through usbfs. I continue to try to follow the directions you posted a year and a half ago, but I continue to get lost, so bare with me. :)
Can you please look over the following email and return it with unnecessary steps removed. I think I remember that I don't need the flattened device tree, but I'm not sure. In the meantime, I have completed the following steps on this page: http://psas.pdx.edu/FlightComputerAv2b/?updated I'm attempting to build the denx tree, but this command make CROSS_COMPILE=powerpc-linux-gnu- ARCH=powerpc tqm5200_defconfig gives this error: Can't find default configuration "arch/powerpc/configs/tqm5200_defconfig"! What step did I miss? Sarah On Wed, Jan 16, 2008 at 3:34 PM, Josh Triplett <j...@freedesktop.org> wrote: > [Sending this to psas-all as a status update.] > > After I stopped working on the flight computer on Wednesday > (2008-01-09), I did some research and I discovered the primary issues > which previously prevented the flight computer from booting Linux 2.6. > I worked on the flight computer for a few hours on Sunday > (2007-01-16), and managed to achieve some good results. The flight > computer can now: > > * Boot Linux 2.6. > * Use an initramfs as its root filesystem. > * Use a busybox initramfs I created, and provide a shell on a serial > port. > * Boot all of the above out of 5MB of the 32MB onboard flash (not the > Compact Flash), with nothing attached other than power and serial > console. > * Access the onboard flash partitions via the MTD driver. > * Access USB devices from Linux. > * Access the Compact Flash card from Linux. > > Short version of the process (mostly of interest to the software and > avionics teams): > > * Newer 2.6 kernels on embedded systems like our TQM5200 (with STK5200 > carrier board in this case) require a "flattened device tree" (fdt), > AKA "device tree blob" (dtb), compiled from the device tree source > (dts) in the Denx kernel source. `apt-get install > device-tree-compiler` for the compiler. Then, build `tqm5200.dtb` > from `tqm5200.dts`, with the command `dtc > ./arch/powerpc/boot/dts/tqm5200.dts -R 4 -S 0x3000 -O dtb -o > /tmp/tqm5200.dtb`. `-R 4` reserves 4 slots for additional maps; an > initramfs needs one, and the u-boot documentation I found recommends > reserving 4. `-S 0x3000` reserves some extra space for u-boot to > extend the map at boot time. > > * Booting kernels with an fdt requires a newer u-boot. Build and > install u-boot from the u-boot Git repository; commit > 6d714f82fb4b8bb7e267e9c71b8009bc670bfe88 worked for me. `make > CROSS_COMPILE=powerpc-linux-gnu- TQM5200_config`, then `make`. > Install mkimage (found in `tools/mkimage`) on the `$PATH`, to build > kernel and initramfs images later. > > * Flash the new `u-boot.bin` to the board using the existing copy of > u-boot. I used the `tftp` command to transfer `u-boot.bin` from my > tftp server to the flight computer's memory, then flashed it to the > firmware partition in the flash address space. (The existing u-boot > included an `update` command to automate flashing the new u-boot.bin > from a given address, so I just used `run update`, but flashing > manually would involve the `unprotect`, `erase`, `cp.b`, and > `protect` commands.) The new u-boot worked on the first try, > fortunate since I would not get a second without a working JTAG or a > wait for shipping. > > * Build a 2.6 kernel from the DENX `linux-2.6-denx` tree, using `make > CROSS_COMPILE=powerpc-linux-gnu- ARCH=powerpc tqm5200_defconfig` > then `make CROSS_COMPILE=powerpc-linux-gnu- ARCH=powerpc uImage`. > This used `mkimage`, and created `arch/powerpc/boot/uImage`. > > * With the new u-boot, tftp the kernel and dtb to the flight > computer's memory (I suggest using the `${kernel_addr_r}` and > `${fdt_addr_r}` variables for the addresses.) Then boot with `bootm > ${kernel_addr_r} - ${fdt_addr_r}`. This should boot the 2.6 kernel > and get as far as failing to mount a root filesystem. > > * You can at this point test booting with a root filesystem from > compact flash or NFS, if you want. > > * TFTP the kernel and dtb again, and flash them to the appropriate > partitions in the onboard flash, designated by the `${kernel_addr}` > and `${fdt_addr}` variables. u-boot does not protect these > partitions, so you just need to use "erase" and "cp.b". Reboot, and > try bootm again with the addresses from flash; this should again > boot as far as trying to find a root filesystem. > > * Grab a copy of the latest busybox release. Build it with `make > CROSS_COMPILE=powerpc-linux-gnu- ARCH=powerpc defconfig`, then > optionally configure differently with `make > CROSS_COMPILE=powerpc-linux-gnu- ARCH=powerpc menuconfig` (or an > alternative config target if you prefer), then build with `make > CROSS_COMPILE=powerpc-linux-gnu- ARCH=powerpc`. Run `make > CROSS_COMPILE=powerpc-linux-gnu- ARCH=powerpc install` to install > busybox and its symlinks to _install in the busybox source > directory. > > * Make a directory for building the initramfs. `cp -a > /path/to/busybox/_install/* initramfs/`. Make a dev directory in > `initramfs/`, and create device files for at least `null`, > `console`, and `ttyPSC0`. In the initramfs directory, run `find . | > cpio -o -H newc | gzip > ../initramfs_data.cpio.gz`. Now, turn that > into a u-boot image with `mkimage -A ppc -T ramdisk -C gzip -n > 'Busybox initramfs' -d ../initramfs_data.cpio.gz ../uRamdisk`. > > * In u-boot, tftp `uRamdisk` to the flight computer's memory. `setenv > bootargs rdinit=/bin/sh`, and booth with `bootm ${kernel_addr} > address_of_uRamdisk ${fdt_addr}`. This should bring up the busybox > shell. > > * Create `/etc/inittab` in the initramfs directory, with the single > line `ttyPSC0::askfirst:/bin/sh`. Re-create the initramfs and the > `uRamdisk`. tftp `uRamdisk` to the flight computer's memory, > `setenv bootargs rdinit=/sbin/init`, and boot with `bootm` again. > The flight computer should boot to busybox init, which starts a > shell when you press enter. > > * Finally, in u-boot, tftp the uRamdisk again and flash it to the > appropriate partition in the onboard flash. Test booting this with > `bootm`. Create a new boot macro with `setenv flash_initramfs > "setenv bootargs rdinit=/sbin/init ; bootm ${kernel_addr} > ${ramdisk_addr} ${fdt_addr}"` and set the flight computer to boot > this by default with `setenv bootcmd "run flash_initramfs"`. > > * The flight computer will now boot unattended into the Linux 2.6 > kernel and busybox init, and interact over the serial console on > PSC0. > > This documentation will go up on the wiki shortly. Since we have > version control for the wiki, any objections to simply removing > obsolete documentation, such as the notes on the PP01 (MENMON) flight > computer, or purchasing info for the 586-based flight computer? > > - Josh Triplett > > _______________________________________________ > psas-all mailing list > psas-...@lists.psas.pdx.edu > http://lists.psas.pdx.edu/mailman/listinfo/psas-all > > This list's membership is automatically generated from the memberships of the > psas-airframe, psas-avionics, psas-general, psas-payload, psas-propulsion, > and psas-software mail lists. Visit http://lists.psas.pdx.edu to individually > subscribe/unsubscribe yourself from these lists. > _______________________________________________ psas-avionics mailing list psas-avionics@lists.psas.pdx.edu http://lists.psas.pdx.edu/mailman/listinfo/psas-avionics
