Tom Rini | 53633a8 | 2024-02-29 12:33:36 -0500 | [diff] [blame] | 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 | |
| 7 | title: | |
| 8 | Samsung Exynos5422 SoC frequency and voltage scaling for Dynamic Memory |
| 9 | Controller device |
| 10 | |
| 11 | maintainers: |
| 12 | - Krzysztof Kozlowski <krzk@kernel.org> |
| 13 | - Lukasz Luba <lukasz.luba@arm.com> |
| 14 | |
| 15 | description: | |
| 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 | |
| 24 | properties: |
| 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 | items: |
| 49 | maxItems: 1 |
| 50 | description: phandles of the PPMU events used by the controller. |
| 51 | |
| 52 | device-handle: |
| 53 | $ref: /schemas/types.yaml#/definitions/phandle |
| 54 | description: | |
| 55 | phandle of the connected DRAM memory device. For more information please |
| 56 | refer to jedec,lpddr3.yaml. |
| 57 | |
| 58 | operating-points-v2: true |
| 59 | |
| 60 | interrupts: |
| 61 | items: |
| 62 | - description: DMC internal performance event counters in DREX0 |
| 63 | - description: DMC internal performance event counters in DREX1 |
| 64 | |
| 65 | interrupt-names: |
| 66 | items: |
| 67 | - const: drex_0 |
| 68 | - const: drex_1 |
| 69 | |
| 70 | reg: |
| 71 | items: |
| 72 | - description: registers of DREX0 |
| 73 | - description: registers of DREX1 |
| 74 | |
| 75 | samsung,syscon-clk: |
| 76 | $ref: /schemas/types.yaml#/definitions/phandle |
| 77 | description: | |
| 78 | Phandle of the clock register set used by the controller, these registers |
| 79 | are used for enabling a 'pause' feature and are not exposed by clock |
| 80 | framework but they must be used in a safe way. The register offsets are |
| 81 | in the driver code and specyfic for this SoC type. |
| 82 | |
| 83 | vdd-supply: true |
| 84 | |
| 85 | required: |
| 86 | - compatible |
| 87 | - clock-names |
| 88 | - clocks |
| 89 | - devfreq-events |
| 90 | - device-handle |
| 91 | - reg |
| 92 | - samsung,syscon-clk |
| 93 | |
| 94 | additionalProperties: false |
| 95 | |
| 96 | examples: |
| 97 | - | |
| 98 | #include <dt-bindings/clock/exynos5420.h> |
| 99 | ppmu_dmc0_0: ppmu@10d00000 { |
| 100 | compatible = "samsung,exynos-ppmu"; |
| 101 | reg = <0x10d00000 0x2000>; |
| 102 | clocks = <&clock CLK_PCLK_PPMU_DREX0_0>; |
| 103 | clock-names = "ppmu"; |
| 104 | events { |
| 105 | ppmu_event_dmc0_0: ppmu-event3-dmc0-0 { |
| 106 | event-name = "ppmu-event3-dmc0_0"; |
| 107 | }; |
| 108 | }; |
| 109 | }; |
| 110 | |
| 111 | memory-controller@10c20000 { |
| 112 | compatible = "samsung,exynos5422-dmc"; |
| 113 | reg = <0x10c20000 0x10000>, <0x10c30000 0x10000>; |
| 114 | clocks = <&clock CLK_FOUT_SPLL>, |
| 115 | <&clock CLK_MOUT_SCLK_SPLL>, |
| 116 | <&clock CLK_FF_DOUT_SPLL2>, |
| 117 | <&clock CLK_FOUT_BPLL>, |
| 118 | <&clock CLK_MOUT_BPLL>, |
| 119 | <&clock CLK_SCLK_BPLL>, |
| 120 | <&clock CLK_MOUT_MX_MSPLL_CCORE>, |
| 121 | <&clock CLK_MOUT_MCLK_CDREX>; |
| 122 | clock-names = "fout_spll", |
| 123 | "mout_sclk_spll", |
| 124 | "ff_dout_spll2", |
| 125 | "fout_bpll", |
| 126 | "mout_bpll", |
| 127 | "sclk_bpll", |
| 128 | "mout_mx_mspll_ccore", |
| 129 | "mout_mclk_cdrex"; |
| 130 | operating-points-v2 = <&dmc_opp_table>; |
| 131 | devfreq-events = <&ppmu_event3_dmc0_0>, <&ppmu_event3_dmc0_1>, |
| 132 | <&ppmu_event3_dmc1_0>, <&ppmu_event3_dmc1_1>; |
| 133 | device-handle = <&samsung_K3QF2F20DB>; |
| 134 | vdd-supply = <&buck1_reg>; |
| 135 | samsung,syscon-clk = <&clock>; |
| 136 | interrupt-parent = <&combiner>; |
| 137 | interrupts = <16 0>, <16 1>; |
| 138 | interrupt-names = "drex_0", "drex_1"; |
| 139 | }; |