[PATCH v4 00/16] Introduce SCMI VirtIO transport

Cristian Marussi
2021-06-11T17:00:24Z

Hi all,

I'm posting this V4 series starting from the work done up to V3 by
OpenSynergy.

I kept original autorship and mailing list distribution unchanged, even
though I'm not really sure if I'm allowed to post to all the original MLs.

The main aim of this rework is to simplify where possible the SCMI VirtIO
support added in V3 by adding upfront and then using some new mechanisms in
the SCMI Core Transport layer.

Indeed patches 01,02,03,04,05 add such additional mechanisms to the SCMI
core; these were previously posted separately in a distinct patchset, I
will retire that series and continue posting those here to ease testing.

In terms of rework I dropped original V3 patches 02,08,12 as no more needed
while keeping for now the rework distinct marking such patches as
[RFC][REWORK] in order to easily spot changes.
(they will be squashed into related original V3 patches next)

DT bindings patch has been ported on top of freshly YAML converted arm,scmi
bindings.

Patch 16 adds support for polling mode to virtio-scmi.

Known/open issues in V4:

- possible violation by virtio-scmi transport of the order constraints on
correlated response/delayed_response messages: this will be addressed
next with changes in the SCMI core.

- probing sequence simplification (if possible)

As such this series is anyway still work in progress, needing also some
general cleanup.

Moreover SCMI core reworks about atomicity and polling, posted as a
distinct series, is not included here either (even though tested against)
and it will kept separate instead for now, to avoid mixing too much stuff
together since not strictly needed for this series.

This V4 series is based on top of next20210610 in order to include all the
recent DT YAML-conversion changes and all the fixes queued as of today in
sudeep/for-next/scmi.

The series has been tested using an emulated fake SCMI device and also a
proper SCP-fw stack running through QEMU vhost-users, with the SCMI stack
compiled, in both cases, as builtin and as s loadable module, running tests
against mocked SCMI Sensors using HWMON and IIO interfaces to check the
functionality of notifications and sync/async commands.

Any feedback/testing is welcome :D

Thanks,
Cristian
---
V3 --> V4:
- dropped V3 patches 02,08,12
- using new delegated xfers support and monotonically increasing tokens
- ported SCMI virtio transport DT bindings to YAML format
- added virtio-scmi polling support

Cristian Marussi (8):
firmware: arm_scmi: Fix max pending messages boundary check
firmware: arm_scmi: Add support for type handling in common functions
firmware: arm_scmi: Add transport optional init/exit support
firmware: arm_scmi: Introduce monotonically increasing tokens
firmware: arm_scmi: Introduce delegated xfers support
[RFC][REWORK] firmware: arm_scmi: Add op to override max message #
[RFC][REWORK] firmware: arm_scmi: make virtio-scmi use delegated xfers
firmware: arm_scmi: Add polling mode to virtio transport

Igor Skalkin (4):
firmware: arm_scmi, smccc, mailbox: Make shmem based transports
optional
firmware: arm_scmi: Add op to override max message #
dt-bindings: arm: Add virtio transport for SCMI
firmware: arm_scmi: Add virtio transport

Peter Hilber (4):
firmware: arm_scmi: Add optional link_supplier() transport op
firmware: arm_scmi: Add per-device transport private info
firmware: arm_scmi: Add is_scmi_protocol_device()
firmware: arm_scmi: Add message passing abstractions for transports

.../bindings/firmware/arm,scmi.yaml | 8 +-
MAINTAINERS | 1 +
drivers/firmware/Kconfig | 26 +-
drivers/firmware/arm_scmi/Makefile | 4 +-
drivers/firmware/arm_scmi/bus.c | 5 +
drivers/firmware/arm_scmi/common.h | 91 ++-
drivers/firmware/arm_scmi/driver.c | 520 +++++++++++++++--
drivers/firmware/arm_scmi/msg.c | 148 +++++
drivers/firmware/arm_scmi/virtio.c | 541 ++++++++++++++++++
drivers/firmware/smccc/Kconfig | 1 +
drivers/mailbox/Kconfig | 1 +
include/uapi/linux/virtio_ids.h | 1 +
include/uapi/linux/virtio_scmi.h | 25 +
13 files changed, 1326 insertions(+), 46 deletions(-)
create mode 100644 drivers/firmware/arm_scmi/msg.c
create mode 100644 drivers/firmware/arm_scmi/virtio.c
create mode 100644 include/uapi/linux/virtio_scmi.h

--
2.17.1