Re: [PATCH V2 1/3] Documentation for system mmu in hi6220 platform.

From: Rob Herring
Date: Wed Oct 21 2015 - 21:15:40 EST


On Tue, Oct 20, 2015 at 3:45 AM, Chen Feng <puck.chen@xxxxxxxxxxxxx> wrote:
> docs: iommu: Documentation for smmu in hi6220 SoC.
>
> Signed-off-by: Chen Feng <puck.chen@xxxxxxxxxxxxx>
> Signed-off-by: Yu Dongbin <yudongbin@xxxxxxxxxxxxx>
> ---
> .../bindings/iommu/hisi,hi6220-iommu.txt | 52 ++++++++++++++++++++++
> 1 file changed, 52 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/iommu/hisi,hi6220-iommu.txt
>
> diff --git a/Documentation/devicetree/bindings/iommu/hisi,hi6220-iommu.txt b/Documentation/devicetree/bindings/iommu/hisi,hi6220-iommu.txt
> new file mode 100644
> index 0000000..93e0701
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iommu/hisi,hi6220-iommu.txt
> @@ -0,0 +1,52 @@
> +Hi6220 SoC SMMU Device Driver devicetree document
> +=======================================================================
> +The Architecture of SMMU on Hi6220 SoC:
> +
> + +------------------------------------------------------------------+
> + | |
> + | +---------+ +--------+ +-------------+ +-------+ |
> + | | ADE | | ISP | | V/J codec | | G3D | |
> + | +----|----+ +---|----+ +------|------+ +---|---| |
> + | | | | | |
> + | ---------v-----------v--------------v--------------v----- |
> + | Media Bus |
> + | --------------------------------|---------------|-------- |
> + | | | |
> + | +---v---------------v--------+ |
> + | | SMMU | |
> + | +----------|---------|-------+ |
> + | | | |
> + +--------------------------------------------|---------|-----------+
> + | |
> + +------------v---------v-----------+
> + | DDRC |
> + +----------------------------------+

Nice diagram.

> +
> +Note:
> +The media system shared the same smmu IP. to access DDR memory. And all
> +media IP used the same page table.
> +
> +Below binding describes the system mmu for media system in hi6220 platform
> +
> +Required properties:
> +- compatible: Should be "hisilicon,hi6220-smmu" example:
> + compatible = "hisilicon,hi6220-smmu";
> +- reg: A tuple of base address and size of System MMU registers.
> +- interrupts: An interrupt specifier for interrupt signal of System MMU.
> +- clocks: The clock used for smmu IP.
> +- clock-names: The name to enable clock with clock framework.
> +- #iommu-cells: The iommu-cells should be 1 for muti-master to use.
> +
> +Examples:
> + smmu@f4210000 {

node name should be iommu.

> + compatible = "hisilicon,hi6220-smmu";
> + reg = <0x0 0xf4210000 0x0 0x1000>;
> + interrupts = <GIC_SPI 113 IRQ_TYPE_LEVEL_HIGH>;
> + clocks = <&sys_ctrl HI6220_MMU_CLK>,
> + <&media_ctrl HI6220_MED_MMU>,
> + <&sys_ctrl HI6220_MEDIA_PLL_SRC>;
> + clock-names = "smmu_clk",
> + "media_sc_clk",
> + "smmu_peri_clk";
> + #iommu-cells = <1>;
> + };
> --
> 1.9.1
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/