1# SPDX-License-Identifier: GPL-2.0
2%YAML 1.2
3---
4$id: http://devicetree.org/schemas/memory-controllers/samsung,exynos5422-dmc.yaml#
5$schema: http://devicetree.org/meta-schemas/core.yaml#
6
7title: |
8  Samsung Exynos5422 SoC frequency and voltage scaling for Dynamic Memory
9  Controller device
10
11maintainers:
12  - Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
13  - Lukasz Luba <lukasz.luba@arm.com>
14
15description: |
16  The Samsung Exynos5422 SoC has DMC (Dynamic Memory Controller) to which the
17  DRAM memory chips are connected. The driver is to monitor the controller in
18  runtime and switch frequency and voltage. To monitor the usage of the
19  controller in runtime, the driver uses the PPMU (Platform Performance
20  Monitoring Unit), which is able to measure the current load of the memory.
21  When 'userspace' governor is used for the driver, an application is able to
22  switch the DMC and memory frequency.
23
24properties:
25  compatible:
26    items:
27      - const: samsung,exynos5422-dmc
28
29  clock-names:
30    items:
31      - const: fout_spll
32      - const: mout_sclk_spll
33      - const: ff_dout_spll2
34      - const: fout_bpll
35      - const: mout_bpll
36      - const: sclk_bpll
37      - const: mout_mx_mspll_ccore
38      - const: mout_mclk_cdrex
39
40  clocks:
41    minItems: 8
42    maxItems: 8
43
44  devfreq-events:
45    $ref: '/schemas/types.yaml#/definitions/phandle-array'
46    minItems: 1
47    maxItems: 16
48    description: phandles of the PPMU events used by the controller.
49
50  device-handle:
51    $ref: '/schemas/types.yaml#/definitions/phandle'
52    description: |
53      phandle of the connected DRAM memory device. For more information please
54      refer to jedec,lpddr3.yaml.
55
56  operating-points-v2: true
57
58  interrupts:
59    items:
60      - description: DMC internal performance event counters in DREX0
61      - description: DMC internal performance event counters in DREX1
62
63  interrupt-names:
64    items:
65      - const: drex_0
66      - const: drex_1
67
68  reg:
69    items:
70      - description: registers of DREX0
71      - description: registers of DREX1
72
73  samsung,syscon-clk:
74    $ref: '/schemas/types.yaml#/definitions/phandle'
75    description: |
76      Phandle of the clock register set used by the controller, these registers
77      are used for enabling a 'pause' feature and are not exposed by clock
78      framework but they must be used in a safe way.  The register offsets are
79      in the driver code and specyfic for this SoC type.
80
81  vdd-supply: true
82
83required:
84  - compatible
85  - clock-names
86  - clocks
87  - devfreq-events
88  - device-handle
89  - reg
90  - samsung,syscon-clk
91
92additionalProperties: false
93
94examples:
95  - |
96    #include <dt-bindings/clock/exynos5420.h>
97    ppmu_dmc0_0: ppmu@10d00000 {
98        compatible = "samsung,exynos-ppmu";
99        reg = <0x10d00000 0x2000>;
100        clocks = <&clock CLK_PCLK_PPMU_DREX0_0>;
101        clock-names = "ppmu";
102        events {
103            ppmu_event_dmc0_0: ppmu-event3-dmc0-0 {
104                event-name = "ppmu-event3-dmc0_0";
105            };
106        };
107    };
108
109    memory-controller@10c20000 {
110        compatible = "samsung,exynos5422-dmc";
111        reg = <0x10c20000 0x10000>, <0x10c30000 0x10000>;
112        clocks = <&clock CLK_FOUT_SPLL>,
113                 <&clock CLK_MOUT_SCLK_SPLL>,
114                 <&clock CLK_FF_DOUT_SPLL2>,
115                 <&clock CLK_FOUT_BPLL>,
116                 <&clock CLK_MOUT_BPLL>,
117                 <&clock CLK_SCLK_BPLL>,
118                 <&clock CLK_MOUT_MX_MSPLL_CCORE>,
119                 <&clock CLK_MOUT_MCLK_CDREX>;
120        clock-names = "fout_spll",
121                      "mout_sclk_spll",
122                      "ff_dout_spll2",
123                      "fout_bpll",
124                      "mout_bpll",
125                      "sclk_bpll",
126                      "mout_mx_mspll_ccore",
127                      "mout_mclk_cdrex";
128        operating-points-v2 = <&dmc_opp_table>;
129        devfreq-events = <&ppmu_event3_dmc0_0>,	<&ppmu_event3_dmc0_1>,
130                         <&ppmu_event3_dmc1_0>, <&ppmu_event3_dmc1_1>;
131        device-handle = <&samsung_K3QF2F20DB>;
132        vdd-supply = <&buck1_reg>;
133        samsung,syscon-clk = <&clock>;
134        interrupt-parent = <&combiner>;
135        interrupts = <16 0>, <16 1>;
136        interrupt-names = "drex_0", "drex_1";
137    };
138