Ticket #11021 (closed defect: fixed)
EC turns on CPU with keyboard unresponsive
|Reported by:||wmb@…||Owned by:||rsmith|
|Component:||embedded controller||Version:||not specified|
|Keywords:||Cc:||dsd, pgf, Quozl, rsmith, sridhar|
|Action Needed:||no action||Verified:||no|
|Deployments affected:||Blocked By:|
Samuel and I have been investigating a keyboard problem on one of his 1.5's. It first showed up as a failure to respond to keyboard during a "more?" prompt inside rocker-induced selftest, but we eventually discovered that it is much more general. The machine will often (about 2 failures in 3 tries) fail to respond to ESC to gain the ok prompt.
We eventually found a way to reproduce the problem on other machines:
One way is to run linux, then "halt", then power off with the button.
Another way is to run OFW, then test /mouse . While running your finger on the touchpad, simultaneously press the power button to turn off the machine. Then power on again. With high probability, you will not be able to break into OFW with the ESC key.
If you use a serial console to inspect the state of the world, you will see that the kbd status register (port 0x64) contains 0x30 instead of 0x10 . This indicates that the PS/2 hardware is in the state "the byte in the output buffer is coming from the touchpad, but there is no byte in the output buffer".
Samuel was able to reproduce the problem with Q3B08 too, but it didn't seem to fail as readily there.
You can see the 0x30 thing very early - just "i to interact" and type
ok 64 pc@ .