mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-12-26 13:03:40 +00:00
c163af6cb8
TISCI protocol supports for enabling the device either with exclusive permissions for the requesting host or with sharing across the hosts. There are certain devices which are exclusive to Linux context and there are certain devices that are shared across different host contexts. So add support for getting this information from DT by increasing the power-domain cells to 2. Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
59 lines
1.8 KiB
Text
59 lines
1.8 KiB
Text
Texas Instruments TI SCI Generic Power Domain
|
|
=============================================
|
|
|
|
Some TI SoCs contain a system controller (like the SYSFW, etc...) that is
|
|
responsible for controlling the state of the IPs that are present.
|
|
Communication between the host processor running an OS and the system
|
|
controller happens through a protocol known as TI SCI [1].
|
|
|
|
[1] http://processors.wiki.ti.com/index.php/TISCI
|
|
|
|
PM Domain Node
|
|
==============
|
|
The PM domain node represents the global PM domain managed by the SYSFW. Because
|
|
this relies on the TI SCI protocol to communicate with the SYSFW it must be a
|
|
child of the sysfw node.
|
|
|
|
Required Properties:
|
|
--------------------
|
|
- compatible: Must be "ti,sci-pm-domain"
|
|
- #power-domain-cells: Can be one of the following:
|
|
1: Containing the device id of each node
|
|
2: First entry should be device id
|
|
Second entry should be one of the floowing:
|
|
TI_SCI_PD_EXCLUSIVE: To allow device to be
|
|
exclusively controlled by
|
|
the requesting hosts.
|
|
TI_SCI_PD_SHARED: To allow device to be shared
|
|
by multiple hosts.
|
|
|
|
Example (AM65x):
|
|
----------------
|
|
sysfw: sysfw {
|
|
compatible = "ti,am654-system-controller";
|
|
...
|
|
k3_pds: power-controller {
|
|
compatible = "ti,sci-pm-domain";
|
|
#power-domain-cells = <1>;
|
|
};
|
|
};
|
|
|
|
PM Domain Consumers
|
|
===================
|
|
Hardware blocks belonging to a PM domain should contain a "power-domains"
|
|
property that is a phandle pointing to the corresponding PM domain node
|
|
along with an index representing the device id to be passed to the PMMC
|
|
for device control.
|
|
|
|
Required Properties:
|
|
--------------------
|
|
- power-domains: phandle pointing to the corresponding PM domain node
|
|
and an ID representing the device.
|
|
|
|
Example (AM65x):
|
|
----------------
|
|
uart2: serial@02800000 {
|
|
compatible = "ti,omap4-uart";
|
|
...
|
|
power-domains = <&k3_pds 0x3f>;
|
|
};
|