| SMI (Smart Multimedia Interface) Common |
| |
| The hardware block diagram please check bindings/iommu/mediatek,iommu.txt |
| |
| Mediatek SMI have two generations of HW architecture, here is the list |
| which generation the SoCs use: |
| generation 1: mt2701 and mt7623. |
| generation 2: mt2712, mt6779, mt8167, mt8173 and mt8183. |
| |
| There's slight differences between the two SMI, for generation 2, the |
| register which control the iommu port is at each larb's register base. But |
| for generation 1, the register is at smi ao base(smi always on register |
| base). Besides that, the smi async clock should be prepared and enabled for |
| SMI generation 1 to transform the smi clock into emi clock domain, but that is |
| not needed for SMI generation 2. |
| |
| Required properties: |
| - compatible : must be one of : |
| "mediatek,mt2701-smi-common" |
| "mediatek,mt2712-smi-common" |
| "mediatek,mt6779-smi-common" |
| "mediatek,mt7623-smi-common", "mediatek,mt2701-smi-common" |
| "mediatek,mt8167-smi-common" |
| "mediatek,mt8173-smi-common" |
| "mediatek,mt8183-smi-common" |
| - reg : the register and size of the SMI block. |
| - power-domains : a phandle to the power domain of this local arbiter. |
| - clocks : Must contain an entry for each entry in clock-names. |
| - clock-names : must contain 3 entries for generation 1 smi HW and 2 entries |
| for generation 2 smi HW as follows: |
| - "apb" : Advanced Peripheral Bus clock, It's the clock for setting |
| the register. |
| - "smi" : It's the clock for transfer data and command. |
| They may be the same if both source clocks are the same. |
| - "async" : asynchronous clock, it help transform the smi clock into the emi |
| clock domain, this clock is only needed by generation 1 smi HW. |
| and these 2 option clocks for generation 2 smi HW: |
| - "gals0": the path0 clock of GALS(Global Async Local Sync). |
| - "gals1": the path1 clock of GALS(Global Async Local Sync). |
| Here is the list which has this GALS: mt6779 and mt8183. |
| |
| Example: |
| smi_common: smi@14022000 { |
| compatible = "mediatek,mt8173-smi-common"; |
| reg = <0 0x14022000 0 0x1000>; |
| power-domains = <&scpsys MT8173_POWER_DOMAIN_MM>; |
| clocks = <&mmsys CLK_MM_SMI_COMMON>, |
| <&mmsys CLK_MM_SMI_COMMON>; |
| clock-names = "apb", "smi"; |
| }; |