On Tue, Mar 05, 2019 at 03:24:03PM +0100, Fabien Dessenne wrote:
> Add the device tree bindings document for the stm32 remoteproc devices.
>
> Signed-off-by: Fabien Dessenne <fabien.dessenne@xxxxxx>
> ---
> .../devicetree/bindings/remoteproc/stm32-rproc.txt | 67 ++++++++++++++++++++++
> 1 file changed, 67 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/remoteproc/stm32-rproc.txt
>
> diff --git a/Documentation/devicetree/bindings/remoteproc/stm32-rproc.txt b/Documentation/devicetree/bindings/remoteproc/stm32-rproc.txt
> new file mode 100644
> index 0000000..cc90c88
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/remoteproc/stm32-rproc.txt
> @@ -0,0 +1,67 @@
> +STMicroelectronics STM32 Remoteproc
> +-----------------------------------
> +This document defines the binding for the remoteproc component that loads and
> +boots firmwares on the ST32MP family chipset.
> +
> +Required properties:
> +- compatible: Must be "st,stm32mp1-rproc"
'rproc' is what this is called in the h/w manual?
> +- reg: Address ranges of the remote processor dedicated memories.
> + The parent node should provide an appropriate ranges property
> + for properly translating these into bus addresses.
> +- resets: Reference to a reset controller asserting the remote processor.
> +- reset-names: Must be "mcu_rst"
-names is kind of pointless when there is only 1 entry.
> +- st,syscfg-holdboot: Reference to the system configuration which holds the
> + remote processor reset hold boot
> + 1st cell: phandle of syscon block
> + 2nd cell: register offset containing the hold boot setting
> + 3rd cell: register bitmask for the hold boot field
> +- st,syscfg-tz: Reference to the system configuration which holds the RCC trust
> + zone mode
> + 1st cell: phandle to syscon block
> + 2nd cell: register offset containing the RCC trust zone mode setting
> + 3rd cell: register bitmask for the RCC trust zone mode bit
> +
> +Optional properties:
> +- interrupt-parent: phandle to the interrupt controller node.
This is implied.
> +- interrupts: Should contain the watchdog interrupt
> +- interrupt-names: Must be "wdg"
-names is kind of pointless when there is only 1 entry.
> +- mboxes: List of phandle and mailbox channel specifiers:
How would one talk to the processor if this is optional?
> + - a channel (a) used to communicate through virtqueues with the
> + remote proc.
> + Bi-directional channel:
> + - from local to remote = send message
> + - from remote to local = send message ack
> + - a channel (b) working the opposite direction of channel (a)
> + - a channel (c) used by the local proc to notify the remote proc
> + that it is about to be shut down.
> + Mono-directional channel:
Unidirectional
> + - from local to remote, where ACK from the remote means
> + that it is ready for shutdown
> +- mbox-names: This property is required if the mboxes property is used.
> + - must be "vq0" for channel (a)
> + - must be "vq1" for channel (b)
> + - must be "shutdown" for channel (c)
> +- memory-region: list of phandles to the reserved memory regions associated with
> + the remoteproc device
> + (see ../reserved-memory/reserved-memory.txt)
How many?
> +- st,syscfg-pdds: Reference to the system configuration which holds the remote
> + processor deep sleep setting
> + 1st cell: phandle to syscon block
> + 2nd cell: register offset containing the deep sleep setting
> + 3rd cell: register bitmask for the deep sleep bit
> +- auto_boot: If defined, when remoteproc is probed, it looks for a default
> + firmware and if it finds some, it loads the firmware and starts
> + the remote processor.
How do you know what is and isn't default firmware? Seems like this
could be accomplished using the standard 'firmware-name' to specify what
firmware to load and boot.
> +- recovery: If defined, remoteproc enables the crash recovery process.
Doesn't seem like a static DT property. This is a feature to enable or
something you set on boot to recover?
> +
> +Example:
> + m4_rproc: m4@0 {
> + compatible = "st,stm32mp1-rproc";
> + reg = <0x00000000 0x10000>,
> + <0x10000000 0x40000>,
> + <0x30000000 0x40000>;
> + resets = <&rcc MCU_R>;
> + reset-names = "mcu_rst";
> + st,syscfg-holdboot = <&rcc 0x10C 0x1>;
> + st,syscfg-tz = <&rcc 0x000 0x1>;
> + };
> --
> 2.7.4
>
