[Skiboot] [PATCH 0/3] Ultravisor SBE chipops

[Thiago Jung Bauermann]

Hello,

On a machine running the Ultravisor, XSCOM addresses used to communicate
with the SBE are restricted and cannot be accessed by Skiboot.

For this reason the Ultravisor provides an ultracall which allows Skiboot
to send commands to the SBE so that it can still use its services. These
commands are SBE_CHIPOP_TIMER, SBE_CHIPOP_HANDLE_INTERRUPT,
SBE_CHIPOP_START_MPIPL.

We use it to set up the timer, to read the SBE doorbell register when
receiving an interrupt from the SBE and for starting an MPIPL.

Many thanks to Ram Pai for his help in designing this feature.

These patches apply on top of Ryan Grimm's Ultravisor support patch series:

https://lists.ozlabs.org/pipermail/skiboot/2020-February/016509.html

Thiago Jung Bauermann (3):
  SBE: Factor out handling of SBE reset
  SBE: Use the Ultravisor to interact with the SBE
  doc/opal-uv-abi.rst: Add information about SBE commands

 doc/opal-uv-abi.rst  |  50 ++++++++++++++++++++-
 hw/sbe-p9.c          | 103 ++++++++++++++++++++++++++++++++++++-------
 include/ultravisor.h |  20 +++++++++
 3 files changed, 154 insertions(+), 19 deletions(-)