xref: /OK3568_Linux_fs/kernel/Documentation/devicetree/bindings/soc/qcom/qcom,aoss-qmp.txt (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593SmuzhiyunQualcomm Always-On Subsystem side channel binding
2*4882a593Smuzhiyun
3*4882a593SmuzhiyunThis binding describes the hardware component responsible for side channel
4*4882a593Smuzhiyunrequests to the always-on subsystem (AOSS), used for certain power management
5*4882a593Smuzhiyunrequests that is not handled by the standard RPMh interface. Each client in the
6*4882a593SmuzhiyunSoC has it's own block of message RAM and IRQ for communication with the AOSS.
7*4882a593SmuzhiyunThe protocol used to communicate in the message RAM is known as Qualcomm
8*4882a593SmuzhiyunMessaging Protocol (QMP)
9*4882a593Smuzhiyun
10*4882a593SmuzhiyunThe AOSS side channel exposes control over a set of resources, used to control
11*4882a593Smuzhiyuna set of debug related clocks and to affect the low power state of resources
12*4882a593Smuzhiyunrelated to the secondary subsystems. These resources are exposed as a set of
13*4882a593Smuzhiyunpower-domains.
14*4882a593Smuzhiyun
15*4882a593Smuzhiyun- compatible:
16*4882a593Smuzhiyun	Usage: required
17*4882a593Smuzhiyun	Value type: <string>
18*4882a593Smuzhiyun	Definition: must be one of:
19*4882a593Smuzhiyun		    "qcom,sc7180-aoss-qmp"
20*4882a593Smuzhiyun		    "qcom,sdm845-aoss-qmp"
21*4882a593Smuzhiyun		    "qcom,sm8150-aoss-qmp"
22*4882a593Smuzhiyun		    "qcom,sm8250-aoss-qmp"
23*4882a593Smuzhiyun
24*4882a593Smuzhiyun- reg:
25*4882a593Smuzhiyun	Usage: required
26*4882a593Smuzhiyun	Value type: <prop-encoded-array>
27*4882a593Smuzhiyun	Definition: the base address and size of the message RAM for this
28*4882a593Smuzhiyun		    client's communication with the AOSS
29*4882a593Smuzhiyun
30*4882a593Smuzhiyun- interrupts:
31*4882a593Smuzhiyun	Usage: required
32*4882a593Smuzhiyun	Value type: <prop-encoded-array>
33*4882a593Smuzhiyun	Definition: should specify the AOSS message IRQ for this client
34*4882a593Smuzhiyun
35*4882a593Smuzhiyun- mboxes:
36*4882a593Smuzhiyun	Usage: required
37*4882a593Smuzhiyun	Value type: <prop-encoded-array>
38*4882a593Smuzhiyun	Definition: reference to the mailbox representing the outgoing doorbell
39*4882a593Smuzhiyun		    in APCS for this client, as described in mailbox/mailbox.txt
40*4882a593Smuzhiyun
41*4882a593Smuzhiyun- #clock-cells:
42*4882a593Smuzhiyun	Usage: optional
43*4882a593Smuzhiyun	Value type: <u32>
44*4882a593Smuzhiyun	Definition: must be 0
45*4882a593Smuzhiyun		    The single clock represents the QDSS clock.
46*4882a593Smuzhiyun
47*4882a593Smuzhiyun- #power-domain-cells:
48*4882a593Smuzhiyun	Usage: optional
49*4882a593Smuzhiyun	Value type: <u32>
50*4882a593Smuzhiyun	Definition: must be 1
51*4882a593Smuzhiyun		    The provided power-domains are:
52*4882a593Smuzhiyun		    CDSP state (0), LPASS state (1), modem state (2), SLPI
53*4882a593Smuzhiyun		    state (3), SPSS state (4) and Venus state (5).
54*4882a593Smuzhiyun
55*4882a593Smuzhiyun= SUBNODES
56*4882a593SmuzhiyunThe AOSS side channel also provides the controls for three cooling devices,
57*4882a593Smuzhiyunthese are expressed as subnodes of the QMP node. The name of the node is used
58*4882a593Smuzhiyunto identify the resource and must therefor be "cx", "mx" or "ebi".
59*4882a593Smuzhiyun
60*4882a593Smuzhiyun- #cooling-cells:
61*4882a593Smuzhiyun	Usage: optional
62*4882a593Smuzhiyun	Value type: <u32>
63*4882a593Smuzhiyun	Definition: must be 2
64*4882a593Smuzhiyun
65*4882a593Smuzhiyun= EXAMPLE
66*4882a593Smuzhiyun
67*4882a593SmuzhiyunThe following example represents the AOSS side-channel message RAM and the
68*4882a593Smuzhiyunmechanism exposing the power-domains, as found in SDM845.
69*4882a593Smuzhiyun
70*4882a593Smuzhiyun  aoss_qmp: qmp@c300000 {
71*4882a593Smuzhiyun	  compatible = "qcom,sdm845-aoss-qmp";
72*4882a593Smuzhiyun	  reg = <0x0c300000 0x100000>;
73*4882a593Smuzhiyun	  interrupts = <GIC_SPI 389 IRQ_TYPE_EDGE_RISING>;
74*4882a593Smuzhiyun	  mboxes = <&apss_shared 0>;
75*4882a593Smuzhiyun
76*4882a593Smuzhiyun	  #power-domain-cells = <1>;
77*4882a593Smuzhiyun
78*4882a593Smuzhiyun	  cx_cdev: cx {
79*4882a593Smuzhiyun		#cooling-cells = <2>;
80*4882a593Smuzhiyun	  };
81*4882a593Smuzhiyun
82*4882a593Smuzhiyun	  mx_cdev: mx {
83*4882a593Smuzhiyun		#cooling-cells = <2>;
84*4882a593Smuzhiyun	  };
85*4882a593Smuzhiyun  };
86