dt-bindings: mediatek: Add binding for mt8183 IOMMU and SMI
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: EMI | M4U | ---------- | | 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: Yong Wu <yong.wu@mediatek.com> Reviewed-by: Rob Herring <robh@kernel.org> Reviewed-by: Evan Green <evgreen@chromium.org> Signed-off-by: Joerg Roedel <jroedel@suse.de>
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