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: 55 Documentation/devicetree/bindings/memory-controllers/ddr/lpddr3.txt 56 57 operating-points-v2: true 58 59 interrupts: 60 items: 61 - description: DMC internal performance event counters in DREX0 62 - description: DMC internal performance event counters in DREX1 63 64 interrupt-names: 65 items: 66 - const: drex_0 67 - const: drex_1 68 69 reg: 70 items: 71 - description: registers of DREX0 72 - description: registers of DREX1 73 74 samsung,syscon-clk: 75 $ref: '/schemas/types.yaml#/definitions/phandle' 76 description: | 77 Phandle of the clock register set used by the controller, these registers 78 are used for enabling a 'pause' feature and are not exposed by clock 79 framework but they must be used in a safe way. The register offsets are 80 in the driver code and specyfic for this SoC type. 81 82 vdd-supply: true 83 84required: 85 - compatible 86 - clock-names 87 - clocks 88 - devfreq-events 89 - device-handle 90 - reg 91 - samsung,syscon-clk 92 93additionalProperties: false 94 95examples: 96 - | 97 #include <dt-bindings/clock/exynos5420.h> 98 ppmu_dmc0_0: ppmu@10d00000 { 99 compatible = "samsung,exynos-ppmu"; 100 reg = <0x10d00000 0x2000>; 101 clocks = <&clock CLK_PCLK_PPMU_DREX0_0>; 102 clock-names = "ppmu"; 103 events { 104 ppmu_event_dmc0_0: ppmu-event3-dmc0-0 { 105 event-name = "ppmu-event3-dmc0_0"; 106 }; 107 }; 108 }; 109 110 memory-controller@10c20000 { 111 compatible = "samsung,exynos5422-dmc"; 112 reg = <0x10c20000 0x10000>, <0x10c30000 0x10000>; 113 clocks = <&clock CLK_FOUT_SPLL>, 114 <&clock CLK_MOUT_SCLK_SPLL>, 115 <&clock CLK_FF_DOUT_SPLL2>, 116 <&clock CLK_FOUT_BPLL>, 117 <&clock CLK_MOUT_BPLL>, 118 <&clock CLK_SCLK_BPLL>, 119 <&clock CLK_MOUT_MX_MSPLL_CCORE>, 120 <&clock CLK_MOUT_MCLK_CDREX>; 121 clock-names = "fout_spll", 122 "mout_sclk_spll", 123 "ff_dout_spll2", 124 "fout_bpll", 125 "mout_bpll", 126 "sclk_bpll", 127 "mout_mx_mspll_ccore", 128 "mout_mclk_cdrex"; 129 operating-points-v2 = <&dmc_opp_table>; 130 devfreq-events = <&ppmu_event3_dmc0_0>, <&ppmu_event3_dmc0_1>, 131 <&ppmu_event3_dmc1_0>, <&ppmu_event3_dmc1_1>; 132 device-handle = <&samsung_K3QF2F20DB>; 133 vdd-supply = <&buck1_reg>; 134 samsung,syscon-clk = <&clock>; 135 interrupt-parent = <&combiner>; 136 interrupts = <16 0>, <16 1>; 137 interrupt-names = "drex_0", "drex_1"; 138 }; 139