[PATCH v1 0/6] MediaTek DVFSRC Bus Bandwidth and Regulator knobs

[AngeloGioacchino Del Regno]

This series adds support for the MediaTek Dynamic Voltage and Frequency
Scaling Resource Controller (DVFSRC), found on many MediaTek SoCs.

This hardware collects requests from both software and the various remote
processors embededd into the SoC, and decides about a minimum operating
voltage and a minimum DRAM frequency to fulfill those requests, in an
effort to provide the best achievable performance per watt.

Such hardware IP is capable of transparently performing direct register
R/W on all of the DVFSRC-controlled regulators and SoC bandwidth knobs.

Summarizing how the DVFSRC works for Interconnect:

             ICC provider         ICC Nodes
                              ----          ----
             _________       |CPU |   |--- |VPU |
    _____   |         |-----  ----    |     ----
   |     |->|  DRAM   |       ----    |     ----
   |DRAM |->|scheduler|----- |GPU |   |--- |DISP|
   |     |->|  (EMI)  |       ----    |     ----
   |_____|->|_________|---.   -----   |     ----
               /|\         `-|MMSYS|--|--- |VDEC|
                |             -----   |     ----
                |                     |     ----
                | change DRAM freq    |--- |VENC|
             --------                 |     ----
    SMC --> | DVFSRC |                |     ----
             --------                 |--- |IMG |
                                      |     ----
                                      |     ----
                                      |--- |CAM |
                                            ----

...and for regulators, it's simply...
   SMC -> DVFSRC -> Regulator voltage decider -> (vreg) Registers R/W

Please note that this series is based on an old (abandoned) series from
MediaTek [1], and reuses some parts of the code found in that.

Besides, included in this series, there's also a refactoring of the
mtk-dvfsrc-regulator driver, which never got compiled at all, and would
not build anyway because of missing headers and typos: that commit did
not get any Fixes tag because, well, backporting makes no sense at all
as the DVFSRC support - which is critical for that driver to work - is
introduced with *this series*! :-)

P.S.: The DVFSRC regulator is a requirement for the MediaTek UFSHCI
      controller's crypto boost feature, which is already upstream but
      lacking the actual regulator to work....... :-)

[1]: https://lore.kernel.org/all/20210812085846.2628-1-dawei.chien@mediatek.com/

Cheers!

AngeloGioacchino Del Regno (6):
  dt-bindings: soc: mediatek: Add DVFSRC bindings for MT8183 and MT8195
  dt-bindings: interconnect: Add MediaTek EMI Interconnect bindings
  dt-bindings: regulator: Add bindings for MediaTek DVFSRC Regulators
  soc: mediatek: Add MediaTek DVFS Resource Collector (DVFSRC) driver
  regulator: mtk-dvfsrc-regulator: Refactor and add MT8192/MT8195 vregs
  interconnect: mediatek: Add MediaTek MT8183/8195 EMI Interconnect
    driver

 .../interconnect/mediatek,mt8183-emi.yaml     |  76 +++
 .../mediatek,mt6873-dvfsrc-regulator.yaml     |  71 +++
 .../soc/mediatek/mediatek,mt8183-dvfsrc.yaml  |  57 ++
 drivers/interconnect/Kconfig                  |   1 +
 drivers/interconnect/Makefile                 |   1 +
 drivers/interconnect/mediatek/Kconfig         |  32 +
 drivers/interconnect/mediatek/Makefile        |   5 +
 drivers/interconnect/mediatek/icc-emi.c       | 153 +++++
 drivers/interconnect/mediatek/icc-emi.h       |  40 ++
 drivers/interconnect/mediatek/mt8183.c        | 143 +++++
 drivers/interconnect/mediatek/mt8195.c        | 339 +++++++++++
 drivers/regulator/mtk-dvfsrc-regulator.c      | 242 ++++----
 drivers/soc/mediatek/Kconfig                  |  11 +
 drivers/soc/mediatek/Makefile                 |   1 +
 drivers/soc/mediatek/mtk-dvfsrc.c             | 551 ++++++++++++++++++
 .../interconnect/mediatek,mt8183.h            |  23 +
 .../interconnect/mediatek,mt8195.h            |  44 ++
 include/linux/soc/mediatek/dvfsrc.h           |  36 ++
 include/linux/soc/mediatek/mtk_sip_svc.h      |   3 +
 19 files changed, 1699 insertions(+), 130 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/interconnect/mediatek,mt8183-emi.yaml
 create mode 100644 Documentation/devicetree/bindings/regulator/mediatek,mt6873-dvfsrc-regulator.yaml
 create mode 100644 Documentation/devicetree/bindings/soc/mediatek/mediatek,mt8183-dvfsrc.yaml
 create mode 100644 drivers/interconnect/mediatek/Kconfig
 create mode 100644 drivers/interconnect/mediatek/Makefile
 create mode 100644 drivers/interconnect/mediatek/icc-emi.c
 create mode 100644 drivers/interconnect/mediatek/icc-emi.h
 create mode 100644 drivers/interconnect/mediatek/mt8183.c
 create mode 100644 drivers/interconnect/mediatek/mt8195.c
 create mode 100644 drivers/soc/mediatek/mtk-dvfsrc.c
 create mode 100644 include/dt-bindings/interconnect/mediatek,mt8183.h
 create mode 100644 include/dt-bindings/interconnect/mediatek,mt8195.h
 create mode 100644 include/linux/soc/mediatek/dvfsrc.h

-- 
2.44.0