[Skiboot] [PATCH] p8-i2c: occ: Add support for OCC to use I2C engines

[Stewart Smith]

Stewart Smith <stewart at linux.vnet.ibm.com> writes:
> From: Shilpasri G Bhat <shilpa.bhat at linux.vnet.ibm.com>
>
> This patch adds support to share the I2C engines with host and OCC.
> OCC uses I2C engines to read DIMM temperatures and to communicate with
> GPU. OCC Flag register is used for locking between host and OCC. Host
> requests for the bus by setting a bit in OCC Flag register. OCC sends
> an interrupt to indicate the change in ownership.
>
> Originally-from: Oliver O'Halloran <oohall at gmail.com>
> Signed-off-by: Shilpasri G Bhat <shilpa.bhat at linux.vnet.ibm.com>
> [stewart at linux.vnet.ibm.com: Pretty heavily rework logic, including
> fixing bus owner change and separating out occ lock from sensor cache]
> Signed-off-by: Stewart Smith <stewart at linux.vnet.ibm.com>
> ---
>  hw/occ.c      |   4 ++
>  hw/p8-i2c.c   | 147 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
>  include/i2c.h |   3 ++
>  3 files changed, 154 insertions(+)

Merged to master as of c5fa0d718e9cda8999dcb83088118a7ea61814c5.

I know this is pretty modified from the original patch, but I spotted a
few issues, especially around getting the locks from the OCC, where the
code would assume it had all the locks, when it could have only gotten
one.


-- 
Stewart Smith
OPAL Architect, IBM.