arm64: zynqmp: Keep SMMU disabled by default

SMMU adds overhead in mapping/un-mapping of DMA buffers. It
will degrade performance numbers for some of the peripherals.
Disabling SMMU to avoid the same.
Please check Xilinx documentation for more information.

Signed-off-by: Mubin Usman Sayyed <mubin.usman.sayyed@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

diff --git a/arch/arm/dts/zynqmp.dtsi b/arch/arm/dts/zynqmp.dtsi
index f40319789759693a6e71bedb61b438e8203a6e30..0bcd6e282ad0f49dab264cd509b1711d6dee1607 100644 (file)
--- a/arch/arm/dts/zynqmp.dtsi
+++ b/arch/arm/dts/zynqmp.dtsi
@@ -370,7 +370,7 @@
                compatible = "arm,mmu-500";
                reg = <0x0 0xfd800000 0x0 0x20000>;
                #iommu-cells = <1>;
-               status = "okay";
+               status = "disabled";
                #global-interrupts = <1>;
                interrupt-parent = <&gic>;
                interrupts = <0 155 4>,