diff options
Diffstat (limited to 'Documentation/devicetree/bindings/iommu/mediatek,iommu.txt')
| -rw-r--r-- | Documentation/devicetree/bindings/iommu/mediatek,iommu.txt | 30 |
1 files changed, 27 insertions, 3 deletions
diff --git a/Documentation/devicetree/bindings/iommu/mediatek,iommu.txt b/Documentation/devicetree/bindings/iommu/mediatek,iommu.txt index 6922db598def..ce59a505f5a4 100644 --- a/Documentation/devicetree/bindings/iommu/mediatek,iommu.txt +++ b/Documentation/devicetree/bindings/iommu/mediatek,iommu.txt @@ -11,10 +11,23 @@ ARM Short-Descriptor translation table format for address translation. | m4u (Multimedia Memory Management Unit) | + +--------+ + | | + gals0-rx gals1-rx (Global Async Local Sync rx) + | | + | | + gals0-tx gals1-tx (Global Async Local Sync tx) + | | Some SoCs may have GALS. + +--------+ + | SMI Common(Smart Multimedia Interface Common) | +----------------+------- | | + | gals-rx There may be GALS in some larbs. + | | + | | + | gals-tx | | SMI larb0 SMI larb1 ... SoCs have several SMI local arbiter(larb). (display) (vdec) @@ -36,6 +49,10 @@ each local arbiter. like display, video decode, and camera. And there are different ports in each larb. Take a example, There are many ports like MC, PP, VLD in the video decode local arbiter, all these ports are according to the video HW. + In some SoCs, there may be a GALS(Global Async Local Sync) module between +smi-common and m4u, and additional GALS module between smi-larb and +smi-common. GALS can been seen as a "asynchronous fifo" which could help +synchronize for the modules in different clock frequency. Required properties: - compatible : must be one of the following string: @@ -44,18 +61,25 @@ Required properties: "mediatek,mt7623-m4u", "mediatek,mt2701-m4u" for mt7623 which uses generation one m4u HW. "mediatek,mt8173-m4u" for mt8173 which uses generation two m4u HW. + "mediatek,mt8183-m4u" for mt8183 which uses generation two m4u HW. - reg : m4u register base and size. - interrupts : the interrupt of m4u. - clocks : must contain one entry for each clock-names. -- clock-names : must be "bclk", It is the block clock of m4u. +- clock-names : Only 1 optional clock: + - "bclk": the block clock of m4u. + Here is the list which require this "bclk": + - mt2701, mt2712, mt7623 and mt8173. + Note that m4u use the EMI clock which always has been enabled before kernel + if there is no this "bclk". - mediatek,larbs : List of phandle to the local arbiters in the current Socs. Refer to bindings/memory-controllers/mediatek,smi-larb.txt. It must sort according to the local arbiter index, like larb0, larb1, larb2... - iommu-cells : must be 1. This is the mtk_m4u_id according to the HW. Specifies the mtk_m4u_id as defined in dt-binding/memory/mt2701-larb-port.h for mt2701, mt7623 - dt-binding/memory/mt2712-larb-port.h for mt2712, and - dt-binding/memory/mt8173-larb-port.h for mt8173. + dt-binding/memory/mt2712-larb-port.h for mt2712, + dt-binding/memory/mt8173-larb-port.h for mt8173, and + dt-binding/memory/mt8183-larb-port.h for mt8183. Example: iommu: iommu@10205000 { |
