[Skiboot] [PATCH v4 09/18] fadump: Define FADUMP structure

Vasant Hegde hegdevasant at linux.vnet.ibm.com
Tue Aug 14 22:10:09 AEST 2018

On 08/07/2018 09:37 AM, Stewart Smith wrote:
> Vasant Hegde <hegdevasant at linux.vnet.ibm.com> writes:
>> This structure is shared between OPAL and payload. During fadump registration
>> payload will use this structure to pass kernel memory reservation details to
>> OPAL. OPAL will use this structure to fill MDST, MDDT table. After fadump,
>> OPAL uses MDRT table to fill this structure and passes this to payload via
>> device tree.


> We alread yhave the OPAL_(UN)REGISTER_DUMP_REGION calls, which look
> really similar to this (and existing kernels support). Why not just use
> these calls instead?

Ideally we should have reused existing APIs. But unfortunately these existing 
one doesn't suite
our requirement here.
OPAL_REGISTER_DUMP_REGION : Passes kernel memory to be copied as part of dump. 
But we
don't have a way to pass destination memory details.

In case of MPIPL kernel will reserve destination memory for kernel memory to be 
We want to pass below information to OPAL:
   source address / size , destination address

Hence I created separate API. Also unlike OPAL_(UN)REGISTER_DUMP_REGION, here we 
use single API for registration,un- registration.


More information about the Skiboot mailing list