[Skiboot] Support for DIMM without ECC

Dean Sanner dsanner at us.ibm.com
Fri Apr 19 05:51:27 AEST 2019

Hi Alexandre,

I'm suspecting not so much of a reset... but that the skiboot code is
targeting the wrong unit within the chip.  Hostboot has a feature
on scom addresses that do translation based on which target you are
attempting to access.  The raw skiboot access will only return the
zero'th unit (skiboot expects the user to do the scom translation).

> > [   51.504955724,5] CHIP: Chip ID 0000 type: P9N
> > DD2.2^M
> > [   51.504992069,3] UPMEM: __xscom_read: gcid, read address gcid:0x0
> > 0x0x603fc38085050

This is socket 0 (base Xscom address of 0x603fc00000000) and the scom
is 0x7010A0A  (0x38085050>>3)

> >  51.72614|FAPI|call_host_start_payload.C: UPMEM: 0x7010a0a value is :
> > *0x8890a23810800000*^M
> >  51.72616|FAPI|call_host_start_payload.C: UPMEM:* PIR: 0x80d*^M

I'm guessing this is not on the zero'th instance of the memory controller
in the chip (there are 8 per socket).  Can you also print out the HUID
to be sure (TARGETING::get_huid(i_target))?

The addresses of the 8 memory controllers in the chip are:

Please let me know if this doesn't help, and I'll dig into the code

Dean Sanner
Dept. DIH, IBM Rochester, MN
(507) 253-7523    t/l 553-7523
dsanner at us.ibm.com

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.ozlabs.org/pipermail/skiboot/attachments/20190418/05b6af25/attachment-0001.htm>

More information about the Skiboot mailing list