1TI Keystone DSP devices
2=======================
3
4The TI Keystone 2 family of SoCs usually have one or more (upto 8) TI DSP Core
5sub-systems that are used to offload some of the processor-intensive tasks or
6algorithms, for achieving various system level goals.
7
8These processor sub-systems usually contain additional sub-modules like L1
9and/or L2 caches/SRAMs, an Interrupt Controller, an external memory controller,
10a dedicated local power/sleep controller etc. The DSP processor core in
11Keystone 2 SoCs is usually a TMS320C66x CorePac processor.
12
13DSP Device Node:
14================
15Each DSP Core sub-system is represented as a single DT node, and should also
16have an alias with the stem 'rproc' defined. Each node has a number of required
17or optional properties that enable the OS running on the host processor (ARM
18CorePac) to perform the device management of the remote processor and to
19communicate with the remote processor.
20
21Required properties:
22--------------------
23The following are the mandatory properties:
24
25- compatible:		Should be one of the following,
26			    "ti,k2hk-dsp" for DSPs on Keystone 2 66AK2H/K SoCs
27			    "ti,k2l-dsp" for DSPs on Keystone 2 66AK2L SoCs
28			    "ti,k2e-dsp" for DSPs on Keystone 2 66AK2E SoCs
29			    "ti,k2g-dsp" for DSPs on Keystone 2 66AK2G SoCs
30
31- reg:			Should contain an entry for each value in 'reg-names'.
32			Each entry should have the memory region's start address
33			and the size of the region, the representation matching
34			the parent node's '#address-cells' and '#size-cells' values.
35
36- reg-names:		Should contain strings with the following names, each
37			representing a specific internal memory region, and
38			should be defined in this order,
39			     "l2sram", "l1pram", "l1dram"
40
41- ti,syscon-dev:	Should be a pair of the phandle to the Keystone Device
42			State Control node, and the register offset of the DSP
43			boot address register within that node's address space.
44
45- resets:		Should contain the phandle to the reset controller node
46			managing the resets for this device, and a reset
47			specifier. Please refer to either of the following reset
48			bindings for the reset argument specifier as per SoC,
49			Documentation/devicetree/bindings/reset/ti-syscon-reset.txt
50			    for 66AK2HK/66AK2L/66AK2E SoCs or,
51			Documentation/devicetree/bindings/reset/ti,sci-reset.yaml
52			    for 66AK2G SoCs
53
54- interrupts: 		Should contain an entry for each value in 'interrupt-names'.
55			Each entry should have the interrupt source number used by
56			the remote processor to the host processor. The values should
57			follow the interrupt-specifier format as dictated by the
58			'interrupt-parent' node. The purpose of each is as per the
59			description in the 'interrupt-names' property.
60
61- interrupt-names:	Should contain strings with the following names, each
62			representing a specific interrupt,
63			    "vring" - interrupt for virtio based IPC
64			    "exception" - interrupt for exception notification
65
66- kick-gpios: 		Should specify the gpio device needed for the virtio IPC
67			stack. This will be used to interrupt the remote processor.
68			The gpio device to be used is as per the bindings in,
69			Documentation/devicetree/bindings/gpio/gpio-dsp-keystone.txt
70
71SoC-specific Required properties:
72---------------------------------
73The following are mandatory properties for Keystone 2 66AK2HK, 66AK2L and 66AK2E
74SoCs only:
75
76- clocks: 		Should contain the device's input clock, and should be
77			defined as per the bindings in,
78			Documentation/devicetree/bindings/clock/keystone-gate.txt
79
80The following are mandatory properties for Keystone 2 66AK2G SoCs only:
81
82- power-domains:	Should contain a phandle to a PM domain provider node
83			and an args specifier containing the DSP device id
84			value. This property is as per the binding,
85			Documentation/devicetree/bindings/soc/ti/sci-pm-domain.yaml
86
87Optional properties:
88--------------------
89
90- memory-region:	phandle to the reserved memory node to be associated
91			with the remoteproc device. The reserved memory node
92			can be a CMA memory node, and should be defined as
93			per the bindings in
94			Documentation/devicetree/bindings/reserved-memory/reserved-memory.txt
95
96
97Examples:
98---------
99
1001.
101	/* 66AK2H/K DSP aliases */
102	aliases {
103		rproc0 = &dsp0;
104		rproc1 = &dsp1;
105		rproc2 = &dsp2;
106		rproc3 = &dsp3;
107		rproc4 = &dsp4;
108		rproc5 = &dsp5;
109		rproc6 = &dsp6;
110		rproc7 = &dsp7;
111	};
112
113	/* 66AK2H/K DSP memory node */
114	reserved-memory {
115		#address-cells = <2>;
116		#size-cells = <2>;
117		ranges;
118
119		dsp_common_memory: dsp-common-memory@81f800000 {
120			compatible = "shared-dma-pool";
121			reg = <0x00000008 0x1f800000 0x00000000 0x800000>;
122			reusable;
123		};
124	};
125
126	/* 66AK2H/K DSP node */
127	soc {
128		dsp0: dsp@10800000 {
129			compatible = "ti,k2hk-dsp";
130			reg = <0x10800000 0x00100000>,
131			      <0x10e00000 0x00008000>,
132			      <0x10f00000 0x00008000>;
133			reg-names = "l2sram", "l1pram", "l1dram";
134			clocks = <&clkgem0>;
135			ti,syscon-dev = <&devctrl 0x40>;
136			resets = <&pscrst 0>;
137			interrupt-parent = <&kirq0>;
138			interrupts = <0 8>;
139			interrupt-names = "vring", "exception";
140			kick-gpios = <&dspgpio0 27 0>;
141			memory-region = <&dsp_common_memory>;
142		};
143
144	};
145
1462.
147	/* 66AK2G DSP alias */
148	aliases {
149		rproc0 = &dsp0;
150	};
151
152	/* 66AK2G DSP memory node */
153	reserved-memory {
154		#address-cells = <2>;
155		#size-cells = <2>;
156		ranges;
157
158		dsp_common_memory: dsp-common-memory@81f800000 {
159			compatible = "shared-dma-pool";
160			reg = <0x00000008 0x1f800000 0x00000000 0x800000>;
161			reusable;
162		};
163	};
164
165	/* 66AK2G DSP node */
166	soc {
167		dsp0: dsp@10800000 {
168			compatible = "ti,k2g-dsp";
169			reg = <0x10800000 0x00100000>,
170			      <0x10e00000 0x00008000>,
171			      <0x10f00000 0x00008000>;
172			reg-names = "l2sram", "l1pram", "l1dram";
173			power-domains = <&k2g_pds 0x0046>;
174			ti,syscon-dev = <&devctrl 0x40>;
175			resets = <&k2g_reset 0x0046 0x1>;
176			interrupt-parent = <&kirq0>;
177			interrupts = <0 8>;
178			interrupt-names = "vring", "exception";
179			kick-gpios = <&dspgpio0 27 0>;
180			memory-region = <&dsp_common_memory>;
181		};
182	};
183