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    dt-bindings: mediatek: Add binding for mt8183 IOMMU and SMI · 29746d01
    Yong Wu authored
    This patch adds decriptions for mt8183 IOMMU and SMI.
    mt8183 has only one M4U like mt8173 and is also MTK IOMMU gen2 which
    uses ARM Short-Descriptor translation table format.
    The mt8183 M4U-SMI HW diagram is as below:
                           |        |
                       gals0-rx   gals1-rx
                           |        |
                           |        |
                       gals0-tx   gals1-tx
                           |        |
                           SMI Common
      |     |     |        |     |     |       |       |
      |     |  gals-rx  gals-rx  |   gals-rx gals-rx gals-rx
      |     |     |        |     |     |       |       |
      |     |     |        |     |     |       |       |
      |     |  gals-tx  gals-tx  |   gals-tx gals-tx gals-tx
      |     |     |        |     |     |       |       |
    larb0 larb1  IPU0    IPU1  larb4  larb5  larb6    CCU
    disp  vdec   img     cam    venc   img    cam
    All the connections are HW fixed, SW can NOT adjust it.
    Compared with mt8173, we add a GALS(Global Async Local Sync) module
    between SMI-common and M4U, and additional GALS between larb2/3/5/6
    and SMI-common. GALS can help synchronize for the modules in different
    clock frequency, it can be seen as a "asynchronous fifo".
    GALS can only help transfer the command/data while it doesn't have
    the configuring register, thus it has the special "smi" clock and it
    doesn't have the "apb" clock. From the diagram above, we add "gals0"
    and "gals1" clocks for smi-common and add a "gals" clock for smi-larb.
    >From the diagram above, IPU0/IPU1(Image Processor Unit) and CCU(Camera
    Control Unit) is connected with smi-common directly, we can take them
    as "larb2", "larb3" and "larb7", and their register spaces are
    different with the normal larb.
    Signed-off-by: default avatarYong Wu <>
    Reviewed-by: default avatarRob Herring <>
    Reviewed-by: default avatarEvan Green <>
    Signed-off-by: default avatarJoerg Roedel <>