stm32mp1: shres: registering shared resources

This change implements a driver for the stm32mp1 resources that may
be assigned to either secure or non-secure worlds upon the platform
configuration.

Other drivers shall register their resources (when applicable) using
the API functions stm32mp_register_{secure|non_secure}_periph*():
- stm32mp_register_*_periph() registers a resource from its
  platform ID.
- stm32mp_register_*_periph_iomem() registers a resource from its
  IOMEM base address.
- stm32mp_register_*_periph_gpio() registers a resource from its
  GPIO reference, bank and position.

Shared resource driver exports some APIs to query a resource
registration state, stm32mp_periph_is_*(),
stm32mp_gpio_bank_is_*(), stm32mp_clock_is_*().

The driver saves the peripheral assignation. The API does not
allow peripherals to change state at runtime. Moverover, to
prevent testing a resource status before it is registered,
the first query on a resource state locks further registering.
Later attempt to register a peripheral will panic the core.

Resources are either secure on non-secure but clock that maybe
shared in which case it will be assigned to the secure world but
a platform service will allow non-secure to access the resource
(i.e. enable/disable the clock). Note such service is out of the
scope of this change, yet this explains API stm32mp_clock_is_shared().

Signed-off-by: Etienne Carriere <etienne.carriere@st.com>
Signed-off-by: Nicolas Le Bayon <nicolas.le.bayon@st.com>
Acked-by: Jens Wiklander <jens.wiklander@linaro.org>

0 files changed, 0 insertions, 0 deletions