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 documentation file: Documentation/devicetree/bindings/ddr/lpddr3.txt 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