xref: /openbmc/u-boot/doc/device-tree-bindings/firmware/nvidia,tegra186-bpmp.txt (revision 7b9cb4940575f3b2d368d56ca06d3c0330af4c4b)
1NVIDIA Tegra Boot and Power Management Processor (BPMP)
2
3The BPMP is a specific processor in Tegra chip, which is designed for
4booting process handling and offloading the power management, clock
5management, and reset control tasks from the CPU. The binding document
6defines the resources that would be used by the BPMP firmware driver,
7which can create the interprocessor communication (IPC) between the CPU
8and BPMP.
9
10Required properties:
11- name : Should be bpmp
12- compatible
13    Array of strings
14    One of:
15    - "nvidia,tegra186-bpmp"
16- mboxes : The phandle of mailbox controller and the mailbox specifier.
17- shmem : List of the phandle of the TX and RX shared memory area that
18	  the IPC between CPU and BPMP is based on.
19- #clock-cells : Should be 1.
20- #power-domain-cells : Should be 1.
21- #reset-cells : Should be 1.
22
23This node is a mailbox consumer. See the following files for details of
24the mailbox subsystem, and the specifiers implemented by the relevant
25provider(s):
26
27- .../mailbox/mailbox.txt
28- .../mailbox/nvidia,tegra186-hsp.txt
29
30This node is a clock, power domain, and reset provider. See the following
31files for general documentation of those features, and the specifiers
32implemented by this node:
33
34- .../clock/clock-bindings.txt
35- <dt-bindings/clock/tegra186-clock.h>
36- ../power/power_domain.txt
37- <dt-bindings/power/tegra186-powergate.h>
38- .../reset/reset.txt
39- <dt-bindings/reset/tegra186-reset.h>
40
41The shared memory bindings for BPMP
42-----------------------------------
43
44The shared memory area for the IPC TX and RX between CPU and BPMP are
45predefined and work on top of sysram, which is an SRAM inside the chip.
46
47See ".../sram/sram.txt" for the bindings.
48
49Example:
50
51hsp_top0: hsp@03c00000 {
52	...
53	#mbox-cells = <2>;
54};
55
56sysram@30000000 {
57	compatible = "nvidia,tegra186-sysram", "mmio-sram";
58	reg = <0x0 0x30000000 0x0 0x50000>;
59	#address-cells = <2>;
60	#size-cells = <2>;
61	ranges = <0 0x0 0x0 0x30000000 0x0 0x50000>;
62
63	cpu_bpmp_tx: bpmp_shmem@4e000 {
64		compatible = "nvidia,tegra186-bpmp-shmem";
65		reg = <0x0 0x4e000 0x0 0x1000>;
66	};
67
68	cpu_bpmp_rx: bpmp_shmem@4f000 {
69		compatible = "nvidia,tegra186-bpmp-shmem";
70		reg = <0x0 0x4f000 0x0 0x1000>;
71	};
72};
73
74bpmp {
75	compatible = "nvidia,tegra186-bpmp";
76	mboxes = <&hsp_top0 HSP_MBOX_TYPE_DB HSP_DB_MASTER_BPMP>;
77	shmem = <&cpu_bpmp_tx &cpu_bpmp_rx>;
78	#clock-cells = <1>;
79	#power-domain-cells = <1>;
80	#reset-cells = <1>;
81};
82