[PATCH v2 0/2] Add the System Timer Module for the NXP S32 architecture

[Daniel Lezcano]

These couple of changes bring the System Timer Module - STM which is
part of the NXP S32 architecture.

The timer module has one counter and four comparators, an interrupt
line when one of the comparator matches the counter. That means the
interrupt is shared across the comparator.

The number of STM is equal to the number of core available on the
system. For the s32g2 variant, there are three Cortex-M3 and four
Cortex-A53, consequently there are seven STM modules dedicated to
those.

In addition, there is a STM variant which is read-only, so the counter
can not be set because it is tied to another STM module dedicated to
timestamp. These special STM modules are apart and will be handled
differently as they can not be used as a clockevent. They are not part
of these changes.

The choice is to have one STM instance, aka one STM description in the
device tree, which initialize a clocksource and a clockevent per
CPU. The latter is assigned to a CPU given the order of their
description. First is CPU0, second is CPU1, etc ...

Changelog:

 - v2:
   - Fixed errors reported by 'make dt_binding_check' (Rob Herring)
   - Removed unneeded '|' symbol (Rob Herring)
   - Removed 'clocks' description (Rob Herring)
   - Removed 'clock-names' because there is only one description (Rob Herring)
   - Renamed 'stm@' to 'timer@' in the DT binding example (Rob Herring)
   - Fixed dt bindings patch subject (Krzysztof Kozlowski)
   - Dropped 'OneOf' in the DT bindings (Krzysztof Kozlowski)
   - Dropped the STM instances structure
   - Use the dev_err_probe() helper (Krzysztof Kozlowski)
   - Use the dev_err_probe() helper (Krzysztof Kozlowski)
   - Use devm_clk_get_enabled() (Krzysztof Kozlowski)
   - Removed unneeded headers (Ghennadi Procopciuc)
   - Removed unused macro (Ghennadi Procopciuc)
   - Replaced 'int' by 'unsigned int' (Ghennadi Procopciuc)
   - Removed dev_set_drvdata() (Ghennadi Procopciuc)
   - Prevent disabling the entire module and set min delta (Ghennadi Procopciuc)
   - Factored out the clocksource / clockevent init routine (Ghennadi Procopciuc)
   - Use devm_request_irq() (Ghennadi Procopciuc.)
   - Use irq_dispose_mapping() for error rollbacking (Ghennadi Procopciuc)

 - v1: initial post

Daniel Lezcano (2):
  dt-bindings: timer: Add NXP System Timer Module
  clocksource/drivers/nxp-timer: Add the System Timer Module for the
    s32g platform

 .../bindings/timer/nxp,stm-timer.yaml         |  50 ++
 drivers/clocksource/Kconfig                   |   9 +
 drivers/clocksource/Makefile                  |   2 +
 drivers/clocksource/timer-nxp-stm.c           | 563 ++++++++++++++++++
 4 files changed, 624 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/timer/nxp,stm-timer.yaml
 create mode 100644 drivers/clocksource/timer-nxp-stm.c

-- 
2.43.0