Hi Marty,
On Tue, 23 Feb 2021 at 16:36, Marty E. Plummer hanetzer@startmail.com wrote:
On Tue, Feb 23, 2021 at 10:10:11AM -0500, Simon Glass wrote:
Hi Marty,
On Thu, 13 Aug 2020 at 13:35, Alper Nebi Yasak alpernebiyasak@gmail.com wrote:
Hi Simon, Marty,
I'm interested in getting U-Boot to work with Kevin as well, but don't have a Servo (or the willingness to open up the case yet), so I've been trying to boot from depthcharge as in README.chromium-chainload.
I don't have a way to see serial output and I see no other signs of life. Can you give me a tested configuration that immediately powers-off or reboots a Kevin so I can confirm what I'm doing works on the chainloading side? I mean I can boot Linux, but trying the same with U-Boot just gives me a blank screen even after accounting for a lot of things.
Meanwhile, I've wrote some code to automate making depthcharge partition images, and to enable the display on Kevin (and perhaps Bob). Since I don't know if chainloading works, I don't know if these are broken or not either. I'm unsure about sending untested patches to the list, so I put them up here if you want to take a look (and maybe test/fix them?):
https://github.com/alpernebbi/u-boot/tree/rk3399-gru-kevin/wip
They're not really things that'd make a non-booting Kevin boot, though. I hope at least some of it can be useful in some way.
I am just replying here as you asked for some details on IRC. What details do you need?
Well, if its possible to actually do openocd/etc on the AP using a servo, I'd like to know how. All the documentation I could find is about using openocd to flash the EC, not debug the AP.
OK...in my case I attached a ARM DSTREAM JTAG unit to the 20-pin connector on the servo 2 board. I was then able to connect and debug U-Boot and linux. This was on a snow (Samsung exynos) so not the same SoC, but it might work. I can't recall the clock speed, but it certainly was slower than 200MHz.
This has some info:
https://elinux.org/images/7/7f/Manderson5.pdf
Here are the instructions I wrote, from the history as they have been removed from the page, being so out of date!
https://sites.google.com/a/google.com/chromeos/system/app/pages/admin/compar...
I was intending to try out a kevin if I have one. I will add that to my list.
Regards, Simon