58 lines
1.7 KiB
Plaintext
58 lines
1.7 KiB
Plaintext
Wakeup M3 IPC Driver
|
|
=====================
|
|
|
|
The TI AM33xx and AM43xx family of devices use a small Cortex M3 co-processor
|
|
(commonly referred to as Wakeup M3 or CM3) to help with various low power tasks
|
|
that cannot be controlled from the MPU, like suspend/resume and certain deep
|
|
C-states for CPU Idle. Once the wkup_m3_ipc driver uses the wkup_m3_rproc driver
|
|
to boot the wkup_m3, it handles communication with the CM3 using IPC registers
|
|
present in the SoC's control module and a mailbox. The wkup_m3_ipc exposes an
|
|
API to allow the SoC PM code to execute specific PM tasks.
|
|
|
|
Wkup M3 Device Node:
|
|
====================
|
|
A wkup_m3_ipc device node is used to represent the IPC registers within an
|
|
SoC.
|
|
|
|
Required properties:
|
|
--------------------
|
|
- compatible: Should be,
|
|
"ti,am3352-wkup-m3-ipc" for AM33xx SoCs
|
|
"ti,am4372-wkup-m3-ipc" for AM43xx SoCs
|
|
- reg: Contains the IPC register address space to communicate
|
|
with the Wakeup M3 processor
|
|
- interrupts: Contains the interrupt information for the wkup_m3
|
|
interrupt that signals the MPU.
|
|
- ti,rproc: phandle to the wkup_m3 rproc node so the IPC driver
|
|
can boot it.
|
|
- mboxes: phandles used by IPC framework to get correct mbox
|
|
channel for communication. Must point to appropriate
|
|
mbox_wkupm3 child node.
|
|
|
|
Example:
|
|
--------
|
|
/* AM33xx */
|
|
l4_wkup: l4_wkup@44c00000 {
|
|
...
|
|
|
|
scm: scm@210000 {
|
|
compatible = "ti,am3-scm", "simple-bus";
|
|
reg = <0x210000 0x2000>;
|
|
#address-cells = <1>;
|
|
#size-cells = <1>;
|
|
ranges = <0 0x210000 0x2000>;
|
|
|
|
...
|
|
|
|
wkup_m3_ipc: wkup_m3_ipc@1324 {
|
|
compatible = "ti,am3352-wkup-m3-ipc";
|
|
reg = <0x1324 0x24>;
|
|
interrupts = <78>;
|
|
ti,rproc = <&wkup_m3>;
|
|
mboxes = <&mailbox &mbox_wkupm3>;
|
|
};
|
|
|
|
...
|
|
};
|
|
};
|