[PATCH 3/3] arm64: dts: rockchip: Disable device link for RK3328 VOP

[Jagan Teki]

Rockchip iommu is trying to enable the VOP device at runtime resume
however VOP device might enable the iommu during their pm runtime resume
operation which indeed leads iommu to use the wrong domain and this
leads to VOP iommu page fault.

This issue is reproduced if we enable the display in U-Boot however
U-Boot is not even touched any iommu register as the U-Boot display
uses the simple frame buffer like other Rockchip platforms RK3399,
and RK3328 do.

rockchip-drm display-subsystem: bound ff370000.vop (ops vop_component_ops)
dwhdmi-rockchip ff3c0000.hdmi: supply avdd-0v9 not found, using dummy regulator
rk_iommu ff373f00.iommu: Enable stall request timed out, status: 0x00004b
dwhdmi-rockchip ff3c0000.hdmi: supply avdd-1v8 not found, using dummy regulator
rk_iommu ff373f00.iommu: Disable paging request timed out, status: 0x00004b
dwhdmi-rockchip ff3c0000.hdmi: Detected HDMI TX controller v2.11a with HDCP (inno_dw_hdmi_phy2)
dwhdmi-rockchip ff3c0000.hdmi: registered DesignWare HDMI I2C bus driver
rockchip-drm display-subsystem: bound ff3c0000.hdmi (ops dw_hdmi_rockchip_ops)
[drm] Initialized rockchip 1.0.0 20140818 for display-subsystem on minor 0

So, prevent this by enabling rockchip,disable-device-link-resume in VOP
node so that VOP enablement for that iommu domain ignored during the
rk_iommu_resume call as it assumes it handled iommu device attachment in
the VOP itself.

Signed-off-by: Jagan Teki <jagan at amarulasolutions.com>
---
 arch/arm64/boot/dts/rockchip/rk3328.dtsi | 1 +
 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/boot/dts/rockchip/rk3328.dtsi b/arch/arm64/boot/dts/rockchip/rk3328.dtsi
index 6d7a7bf72ac7..7ca83bc844c1 100644
--- a/arch/arm64/boot/dts/rockchip/rk3328.dtsi
+++ b/arch/arm64/boot/dts/rockchip/rk3328.dtsi
@@ -718,6 +718,7 @@ vop_mmu: iommu at ff373f00 {
 		clocks = <&cru ACLK_VOP>, <&cru HCLK_VOP>;
 		clock-names = "aclk", "iface";
 		#iommu-cells = <0>;
+		rockchip,disable-device-link-resume;
 		status = "disabled";
 	};
 
-- 
2.25.1