Kernel-4.18.0-80.el8_rockchip,iommu

Rockchip IOMMU

A Rockchip DRM iommu translates io virtual addresses to physical addresses for
its master device. Each slave device is bound to a single master device, and
shares its clocks, power domain and irq.

Required properties:

  • compatible : Should be “rockchip,iommu”
  • reg : Address space for the configuration registers
  • interrupts : Interrupt specifier for the IOMMU instance
  • interrupt-names : Interrupt name for the IOMMU instance
  • #iommu-cells : Should be <0>. This indicates the iommu is a
                  "single-master" device, and needs no additional information
                  to associate with its master device.  See:
                  Documentation/devicetree/bindings/iommu/iommu.txt
    
  • clocks : A list of clocks required for the IOMMU to be accessible by
                  the host CPU.
    
  • clock-names : Should contain the following:
    “iface” - Main peripheral bus clock (PCLK/HCL) (required)
    “aclk” - AXI bus clock (required)

Optional properties:

  • rockchip,disable-mmu-reset : Don’t use the mmu reset operation.
                 Some mmu instances may produce unexpected results
                 when the reset operation is used.
    

Example:

vopl_mmu: iommu@ff940300 {
    compatible = "rockchip,iommu";
    reg = <0xff940300 0x100>;
    interrupts = <GIC_SPI 16 IRQ_TYPE_LEVEL_HIGH>;
    interrupt-names = "vopl_mmu";
    clocks = <&cru ACLK_VOP1>, <&cru HCLK_VOP1>;
    clock-names = "aclk", "iface";
    #iommu-cells = <0>;
};