[Skiboot] [PATCH] hmi: Clear unknown debug trigger

[Stewart Smith]

Michael Neuling <mikey at neuling.org> writes:
> From: Ryan Grimm <grimm at linux.vnet.ibm.com>
>
> On some systems, seeing hangs like this when Linux starts:
>   [ 170.027252763,5] OCC: All Chip Rdy after 0 ms
>   [ 170.062930145,5] INIT: Starting kernel at 0x20011000, fdt at 0x30ae0530 366247 bytes)
>   [ 171.238270428,5] OPAL: Switch to little-endian OS
>
> If you look at the in memory skiboot console (or do 'nvram -p
> ibm,skiboot --update-config log-level-driver=7') we see the console get
> spammed with:
>   [ 5209.109790675,7] HMI: Received HMI interrupt: HMER = 0x0000400000000000
>   [ 5209.109792716,7] HMI: Received HMI interrupt: HMER = 0x0000400000000000
>   [ 5209.109794695,7] HMI: Received HMI interrupt: HMER = 0x0000400000000000
>   [ 5209.109796689,7] HMI: Received HMI interrupt: HMER = 0x0000400000000000
>
> We're taking the debug trigger (bit 17) early on, before the
> hmi_debug_trigger function in the kernel is set up.
>
> This clears the HMI in Skiboot and reports to the kernel instead of
> bringing down the machine.
>
> Signed-off-by: Ryan Grimm <grimm at linux.vnet.ibm.com>
> Signed-off-by: Michael Neuling <mikey at neuling.org>
> ---
>  core/hmi.c | 10 ++++++++++
>  1 file changed, 10 insertions(+)

Thanks. Looks like we may have another issue when we get a flood of them
before linux is up, but hey, what is opalmsg for if not filling the heap
with useless stuff? :)

Merged to master as of eddff9bf40cfbd6e2ac36012607173e6e299267a

-- 
Stewart Smith
OPAL Architect, IBM.