Re: [PATCH v2 4/7] ARM: dts: rockchip: add virtual iommu for display

Hi,

On Wed, Jun 8, 2016 at 10:26 PM, Shunqian Zheng zhengsq@rock-chips.com wrote:

An virtual iommu without reg or interrupts for display. Adding this according to iommu driver changes.

Signed-off-by: Shunqian Zheng zhengsq@rock-chips.com

arch/arm/boot/dts/rk3288.dtsi | 6 ++++++ 1 file changed, 6 insertions(+)

diff --git a/arch/arm/boot/dts/rk3288.dtsi b/arch/arm/boot/dts/rk3288.dtsi index 7fa932f..4cd535f 100644 --- a/arch/arm/boot/dts/rk3288.dtsi +++ b/arch/arm/boot/dts/rk3288.dtsi @@ -219,9 +219,15 @@ clock-names = "timer", "pclk"; };

•   display_mmu: virtual-iommu {
  

•           compatible = "rockchip,iommu";
  

•           #iommu-cells = <0>;
  

•   };
  

Device tree should describe real hardware and so it isn't really a good idea to add such virtual iommu, especially using a compatible string of a real device.

Please see my comments to patch 3/7 for an alternative idea.

Best regards, Tomasz