[Skiboot] [PATCH v11 03/11] skiboot: Add chip id to HOMER reserved region

Stewart Smith stewart at linux.vnet.ibm.com
Fri May 12 11:20:58 AEST 2017

Madhavan Srinivasan <maddy at linux.vnet.ibm.com> writes:
> From: Vasant Hegde <hegdevasant at linux.vnet.ibm.com>
> This patch adds a "ibm,chip-id" property to HOMER reserved region. That
> helps us in relating the HOMER reserved region to the chip that its
> associated with.
> This patch is required for nest IMC counters since, the counter values
> are stored in an offset inside the HOMER region. To read those values
> from the kernel for a chip, we need to associate the region to its
> associated chip.
> Signed-off-by: Vasant Hegde <hegdevasant at linux.vnet.ibm.com>
> Signed-off-by: Hemant Kumar <hemant at linux.vnet.ibm.com>
> Signed-off-by: Madhavan Srinivasan <maddy at linux.vnet.ibm.com>
> ---
>  core/init.c       |  3 +++
>  hw/homer.c        | 30 ++++++++++++++++++++++++++++++
>  include/skiboot.h |  1 +
>  3 files changed, 34 insertions(+)

As mentioned in review of the kernel patch (see
https://patchwork.ozlabs.org/patch/758583/ ) I think it woul be better
that if instead of keying everything to /reserved-memory/ibm,homer-image
we just provided a base address either directly in the IMC DT part or
have a phandle reference to the reserved-memory region that's

This would give us flexibility in the interface to the kernel, and not
tie us to counters in the ibm,homer-image.

Stewart Smith
OPAL Architect, IBM.

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