[v7,00/14] Add support for Mobileye EyeQ5 system controller

Hi,

The goal of this series is to add clk, reset and pinctrl support for the
Mobileye EyeQ5 platform [0]. Control of those is grouped inside a
system controller block called "OLB".

About clocks, we replaced the 10 fixed clocks from the initial platform
support series [0] by 10 read-only fixed-factor PLLs provided by our
clock driver. We also provide one table-based divider clock for OSPI.
Two PLLs (for GIC timer & UARTs) are required at of_clk_init() so those
are registered first, the rest comes at platform device probe.

Resets are split in three domains, all dealt with by the same device.
They have some behavior differences:
 - We busy-wait on the first two for hardware LBIST reasons (logic
   built-in self-test).
 - Domains 0 & 2 work in a bit-per-reset fashion while domain 1 works in
   a register-per-reset fashion.

Pin control is about controlling bias, drive strength and muxing. The
latter allows two functions per pin; the first function is always GPIO
while the second one is pin-dependent. There exists two banks, both
handled by a single driver instance. Each pin maps to one pin group.
That makes pin & group indexes the same, simplifying logic.

The patch adding the system-controller dt-bindings ("dt-bindings: soc:
mobileye: add EyeQ5 OLB system controller") is dependent on the three
controllers dt-bindings:
 - dt-bindings: clock: mobileye,eyeq5-clk: add bindings
 - dt-bindings: reset: mobileye,eyeq5-reset: add bindings
 - dt-bindings: pinctrl: mobileye,eyeq5-pinctrl: add bindings

The parent is v6.8-rc5 with both [1] and [0] series applied on top. Both
series are in mips-next [2].

Here is the patch list, split by subsystems:

- clk:
   [PATCH v7 01/14] clk: fixed-factor: add optional accuracy support
   [PATCH v7 02/14] clk: fixed-factor: add fwname-based constructor functions
   [PATCH v7 03/14] dt-bindings: clock: mobileye,eyeq5-clk: add bindings
   [PATCH v7 07/14] clk: eyeq5: add platform driver, and init routine at of_clk_init()
- pinctrl:
   [PATCH v7 05/14] dt-bindings: pinctrl: mobileye,eyeq5-pinctrl: add bindings
   [PATCH v7 09/14] pinctrl: eyeq5: add platform driver
- reset:
   [PATCH v7 04/14] dt-bindings: reset: mobileye,eyeq5-reset: add bindings
   [PATCH v7 08/14] reset: eyeq5: add platform driver
- MIPS: (note: dependent on the [0] series)
   [PATCH v7 06/14] dt-bindings: soc: mobileye: add EyeQ5 OLB system controller
   [PATCH v7 10/14] MAINTAINERS: Map OLB files to Mobileye SoCs
   [PATCH v7 11/14] MIPS: mobileye: eyeq5: add OLB syscon node
   [PATCH v7 12/14] MIPS: mobileye: eyeq5: use OLB clocks controller node
   [PATCH v7 13/14] MIPS: mobileye: eyeq5: add OLB reset controller node
   [PATCH v7 14/14] MIPS: mobileye: eyeq5: add pinctrl node & pinmux function nodes

Thanks all for the previous feedback!

Have a nice day,
Théo Lebrun

[0]: https://lore.kernel.org/lkml/20240216174227.409400-1-gregory.clement@bootlin.com/
[1]: https://lore.kernel.org/linux-mips/20240209-regname-v1-0-2125efa016ef@flygoat.com/
[2]: https://git.kernel.org/pub/scm/linux/kernel/git/mips/linux.git/log/

Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
---
Changes in v7:
- pinctrl: use dev_err_probe() and lower first letter of messages.
- Move all MAINTAINERS changes to a separate patch aimed at the MIPS
  tree. This means clk/reset/pinctrl can take patches independently.
- Apply two Reviewed-by: Linus Walleij.
- Link to v6: https://lore.kernel.org/r/20240212-mbly-clk-v6-0-c46fa1f93839@bootlin.com

Changes in v6:
- bindings/clk: remove minItems in reg.
- bindings/reset: remove minItems in reg.
- bindings/syscon: unify quotes (use single quotes everywhere).
- bindings: apply three Reviewed-By tags from Krzysztof.
- Rebased onto v6.8-rc5. No related changes. Tested on EyeQ5 hardware.
- Link to v5: https://lore.kernel.org/r/20240209-mbly-clk-v5-0-f094ee5e918a@bootlin.com

Changes in v5:
- pinctrl: fix pin/offset distinction, add eq5p_pin_to_offset() helper,
  rename eq5p_pin_offset_to_bank() to eq5p_pin_to_bank(), rename
  eq5p_readl_bit() to eq5p_test_bit(), remove old <linux/mfd/syscon.h>
  include, add defensive check in eq5p_test_bit().
- dt-bindings/MIPS: OLB example (dt-bindings) and devicetree: fix
  ordering of nodes and properties, fix register casing.
- dt-bindings: add pin group node example to OLB dt-bindings.
- MIPS: squashed "MIPS: mobileye: eyeq5: add reset properties to UARTs"
  into "MIPS: mobileye: eyeq5: add OLB reset controller node".
- MIPS: squashed "MIPS: mobileye: eyeq5: add pinctrl properties to UART
  nodes" into "MIPS: mobileye: eyeq5: add pinctrl node & pinmux
  function nodes".
- MIPS: rebased onto V7 of [0], meaning we now introduce the OLB syscon
  node in DT in this series rather than modifying it.
- Apply Reviewed-by from Rob onto "dt-bindings: pinctrl:
  mobileye,eyeq5-pinctrl: add bindings".
- dt-bindings: Drop "dt-bindings: pinctrl: allow pin controller device
  without unit address".
- dt-bindings: I did NOT apply Krzysztof's Reviewed-By trailers from v3
  as I am not sure he acked the changes made in V4.
- Link to v4: https://lore.kernel.org/r/20240131-mbly-clk-v4-0-bcd00510d6a0@bootlin.com

Changes in v4:
- Have the three drivers access MMIO directly rather than through the
  syscon & regmap.
- pinctrl: Make the pin controller handle both banks using a single
  instance.
- pinctrl/dt-bindings: Add if/else for each function, to strictly define
  possible functions.
- clk: Changing to direct MMIO means we can use
  clk_hw_register_divider_table_parent_hw() for the OSPI table-based
  divider clock.
- Use builtin_platform_driver() for platform driver registering instead
  of manual initcalls.
- reset: follow Philipp & Krzysztof's feedback:
  - Use container_of() to get private struct.
  - Use '_withlock' suffix instead of the underscore prefix.
  - Use udelay() instead of the non-standard __udelay().
  - Remove useless checks.
  - Use mutex guards.
  - Remove the ->reset() implementation.
  - Use devres variants for kzalloc() and reset_controller_register().
- Other small changes following feedback from reviewers. dt-bindings
  whitespace for pinctrl.yaml, fix pinctrl driver dt-bindings
  description, improve clk driver commit header, etc.
- Link to v3: https://lore.kernel.org/r/20240123-mbly-clk-v3-0-392b010b8281@bootlin.com

Changes in v3:
- Unified the three series into one.
- clk: split driver into two for clocks registered at of_clk_init() and
  clocks registered at platform device probe.
- reset/bindings: drop reset dt-bindings header & add comment in driver
  to document known valid resets in each domain.
- pinctrl/bindings: fix pinctrl.yaml to allow non unit addresses for pin
  controller devices.
- all/bindings: remove possibility to use `mobileye,olb` phandle to get
  syscon. All three drivers use their parent node as syscon/regmap.
- MIPS/bindings: fix bindings for OLB. Have single example in parent,
  removing all examples in child.
- all: drop the "probed" logs.
- Link to v2: https://lore.kernel.org/r/20231227-mbly-clk-v2-0-a05db63c380f@bootlin.com

Changes in v2:
- Drop [PATCH 1/5] that was taken by Stephen for clk-next.
- Add accuracy support to fixed-factor that is enabled with a flag.
  Register prototypes were added to exploit this feature.
- Add fw_name support to fixed-factor. This allows pointing to parent
  clocks using the value in `clock-names` in the DT. Register
  prototypes were added for that.
- Bindings were modified to be less dumb: a binding was added for OLB
  and the clock-controller is a child property of it. Removed the
  possibility of pointing to OLB using a phandle. $nodename is the
  generic `clock-controller` and not custom `clocks`. Fix dt-bindings
  examples.
- Fix commit message for the driver patch. Add details, remove useless
  fluff.
- Squash both driver commits together.
- Declare a platform_driver instead of using CLK_OF_DECLARE_DRIVER. This
  also means using `dev_*` for logging, removing `pr_fmt`. We add a
  pointer to device in the private structure.
- Use fixed-factor instead of fixed-rate for PLLs. We don't grab a
  reference to the parent clk, instead using newly added fixed-factor
  register prototypes and fwname.
- NULL is not an error when registering PLLs anymore.
- Now checking the return value of of_clk_add_hw_provider for errors.
- Fix includes.
- Remove defensive conditional at start of eq5c_pll_parse_registers.
- Rename clk_hw_to_ospi_priv to clk_to_priv to avoid confusion: it is
  not part of the clk_hw_* family of symbols.
- Fix negative returns in eq5c_ospi_div_set_rate. It was a typo
  highlighted by Stephen Boyd.
- Declare eq5c_ospi_div_ops as static.
- In devicetree, move the OLB node prior to the UARTs, as platform
  device probe scheduling is dependent on devicetree ordering. This is
  required to declare the driver as a platform driver, else it
  CLK_OF_DECLARE_DRIVER is required.
- In device, create a core0-timer-clk fixed clock to feed to the GIC
  timer. It requires a clock earlier than platform bus type init.
- Link to v1: https://lore.kernel.org/r/20231218-mbly-clk-v1-0-44ce54108f06@bootlin.com

---
Théo Lebrun (14):
      clk: fixed-factor: add optional accuracy support
      clk: fixed-factor: add fwname-based constructor functions
      dt-bindings: clock: mobileye,eyeq5-clk: add bindings
      dt-bindings: reset: mobileye,eyeq5-reset: add bindings
      dt-bindings: pinctrl: mobileye,eyeq5-pinctrl: add bindings
      dt-bindings: soc: mobileye: add EyeQ5 OLB system controller
      clk: eyeq5: add platform driver, and init routine at of_clk_init()
      reset: eyeq5: add platform driver
      pinctrl: eyeq5: add platform driver
      MAINTAINERS: Map OLB files to Mobileye SoCs
      MIPS: mobileye: eyeq5: add OLB syscon node
      MIPS: mobileye: eyeq5: use OLB clocks controller node
      MIPS: mobileye: eyeq5: add OLB reset controller node
      MIPS: mobileye: eyeq5: add pinctrl node & pinmux function nodes

 .../bindings/clock/mobileye,eyeq5-clk.yaml         |  51 ++
 .../bindings/pinctrl/mobileye,eyeq5-pinctrl.yaml   | 242 +++++++++
 .../bindings/reset/mobileye,eyeq5-reset.yaml       |  43 ++
 .../bindings/soc/mobileye/mobileye,eyeq5-olb.yaml  |  94 ++++
 MAINTAINERS                                        |   8 +
 .../{eyeq5-fixed-clocks.dtsi => eyeq5-clocks.dtsi} |  54 +-
 arch/mips/boot/dts/mobileye/eyeq5-pins.dtsi        | 125 +++++
 arch/mips/boot/dts/mobileye/eyeq5.dtsi             |  42 +-
 drivers/clk/Kconfig                                |  11 +
 drivers/clk/Makefile                               |   1 +
 drivers/clk/clk-eyeq5.c                            | 289 +++++++++++
 drivers/clk/clk-fixed-factor.c                     | 103 +++-
 drivers/pinctrl/Kconfig                            |  15 +
 drivers/pinctrl/Makefile                           |   1 +
 drivers/pinctrl/pinctrl-eyeq5.c                    | 577 +++++++++++++++++++++
 drivers/reset/Kconfig                              |  12 +
 drivers/reset/Makefile                             |   1 +
 drivers/reset/reset-eyeq5.c                        | 342 ++++++++++++
 include/dt-bindings/clock/mobileye,eyeq5-clk.h     |  22 +
 include/linux/clk-provider.h                       |  26 +-
 20 files changed, 2003 insertions(+), 56 deletions(-)
---
base-commit: 96ba7d34f557251d2416ff93c205003eba3cf3db
change-id: 20231023-mbly-clk-87ce5c241f08

Best regards,