[PATCH v5 0/6] Add support for mt8183 SCP.

[Pi-Hsun Shih <pihsun@chromium.org>]

Add support for controlling and communicating with mt8183's system
control processor (SCP), using the remoteproc & rpmsg framework.
And also add a cros_ec driver for CrOS EC host command over rpmsg.

The overall structure of the series is:
* remoteproc/mtk_scp.c: Control the start / stop of SCP (Patch 2, 3).
* remoteproc/mtk_scp_ipi.c: Communicates to SCP using inter-processor
  interrupt (IPI) and shared memory (Patch 2, 3).
* rpmsg/mtk_rpmsg.c: Wrapper to wrap the IPI communication into a rpmsg
  device. Supports name service for SCP firmware to
  announce channels (Patch 4).
* platform/chrome/cros_ec_rpmsg.c: Communicates with the SCP over the
  rpmsg framework (like what platform/chrome/cros_ec_{i2c,spi}.c does)
  (Patch 5, 6).

Since I'm not familiar with the remoteproc / rpmsg framework, and there
are not much other custom rpmsg driver for reference, would like some
review / comments on the overall structure of the driver.

Changes from v4:
 - Merge patch 6 (Load ELF firmware) into patch 2, so the driver loads
   ELF firmware by default, and no longer accept plain binary.
 - rpmsg_device listed in device tree (as a child of the SCP node) would
   have it's device tree node mapped to the rpmsg_device, so the rpmsg
   driver can use the properties on device tree.

Changes from v3:
 - Make writing to SCP SRAM aligned.
 - Add a new patch (Patch 6) to load ELF instead of bin firmware.
 - Add host event support for EC driver.
 - Fix some bugs found in testing (missing spin_lock_init,
   rproc_subdev_unprepare to rproc_subdev_stop).
 - Fix some coding style issue found by checkpatch.pl.

Changes from v2:
 - Fold patch 3 into patch 2 in v2.
 - Move IPI id around to support cross-testing for old and new firmware.
 - Finish more TODO items.

Changes from v1:
 - Extract functions and rename variables in mtk_scp.c.
 - Do cleanup properly in mtk_rpmsg.c, which also removes the problem of
   short-lived work items.
 - Code format fix based on feedback for cros_ec_rpmsg.c.
 - Extract feature detection for SCP into separate patch (Patch 6).

Erin Lo (3):
  dt-bindings: Add a binding for Mediatek SCP
  remoteproc/mediatek: add SCP support for mt8183
  remoteproc: mt8183: add reserved memory manager API

Pi-Hsun Shih (3):
  rpmsg: add rpmsg support for mt8183 SCP.
  mfd: add EC host command support using rpmsg.
  cros_ec: differentiate SCP from EC by feature bit.

 .../bindings/remoteproc/mtk,scp.txt           |  37 ++
 drivers/mfd/cros_ec_dev.c                     |   9 +
 drivers/platform/chrome/Kconfig               |   9 +
 drivers/platform/chrome/Makefile              |   1 +
 drivers/platform/chrome/cros_ec_rpmsg.c       | 248 +++++++
 drivers/remoteproc/Kconfig                    |   9 +
 drivers/remoteproc/Makefile                   |   1 +
 drivers/remoteproc/mtk_common.h               |  77 +++
 drivers/remoteproc/mtk_scp.c                  | 628 ++++++++++++++++++
 drivers/remoteproc/mtk_scp_ipi.c              | 163 +++++
 drivers/rpmsg/Kconfig                         |   9 +
 drivers/rpmsg/Makefile                        |   1 +
 drivers/rpmsg/mtk_rpmsg.c                     | 385 +++++++++++
 include/linux/mfd/cros_ec.h                   |   1 +
 include/linux/mfd/cros_ec_commands.h          |   2 +
 include/linux/platform_data/mtk_scp.h         | 157 +++++
 include/linux/rpmsg/mtk_rpmsg.h               |  35 +
 17 files changed, 1772 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/remoteproc/mtk,scp.txt
 create mode 100644 drivers/platform/chrome/cros_ec_rpmsg.c
 create mode 100644 drivers/remoteproc/mtk_common.h
 create mode 100644 drivers/remoteproc/mtk_scp.c
 create mode 100644 drivers/remoteproc/mtk_scp_ipi.c
 create mode 100644 drivers/rpmsg/mtk_rpmsg.c
 create mode 100644 include/linux/platform_data/mtk_scp.h
 create mode 100644 include/linux/rpmsg/mtk_rpmsg.h

-- 
2.21.0.rc0.258.g878e2cd30e-goog