Dave Martin wrote:
On Fri, Feb 25, 2011 at 10:58 AM, Loďc Minier loic.minier@linaro.org wrote:
On Thu, Feb 24, 2011, Mounir Bsaibes wrote:
We have a need for a Panda and a Beagle to compare & fix performance. As I recall from last meeting, the Panda's USB I/O has 2x performance degradation from Beagle. Per or Mian may have more details on that.
Ok; interesting!
My initial fear was that the kernel testing might trigger unbootable boards and that it would be tricky to work with unstable kernels remotely; for USB performance testing, I can see that we could set it up for remote testing, but we need to have something plugged to USB
and
be careful to use the same hardware on both boards so that it
compares
usefully.
If we never upgrade the bootloader, and make sure that the known-good bootscripts/images are never modified/removed, then we should generally be able to avoid bricking.
On vexpress for example, we have a known-good U-Boot in flash which can be used to recover the board if needed.
Where random hardware has to be plugged in, that could be a bit harder to arrange...
I work remotely with my Pandaboard - I have the UART plugged into a desktop and a USB relay board for the power supply. I have a screen session with picocom running on the desktop all the time.
I keep known-working loaders on the SD card with a "uImage-flasher" image alongside. (Essentially a kernel with drivers enabled for the EHCI controller and the USB-LAN chip + initramfs + tiny scripts that pick up a kernel image from a hardcoded location using tftp and replace the one currently on the SD card.
To get into the flasher image, I just halt manually in u-boot and load uimage-flasher. Else, u-boot is configured to pick up 'uImage' by default.
Issues: - Can't work remotely if you're working on x-loader code (flashing a wrong image MLO/u-boot could mean a physical visit to the board) --- Okay for u-boot if you want to load u-boot from within a known- working u-boot. - Someone 'borrows' the board without asking. --- I've had folks walk in, see the board apparently unused, and borrow it for a - leaving me wondering why the board stopped responding. :(
- Anand