The imx6 SMP system has the same DMA memory coherency issue [1] with
pl310 L2 controller. With this shared override bit set, the customer
reports the DMA coherency issue is gone. Besides, I have tested
the performance using USB ethernet with/without this bit, it shows
no difference.
[1] http://patchwork.ozlabs.org/patch/469362/
Signed-off-by: Peter Chen <redacted>
---
arch/arm/boot/dts/imx6qdl.dtsi | 1 +
1 file changed, 1 insertion(+)
diff --git a/arch/arm/boot/dts/imx6qdl.dtsi b/arch/arm/boot/dts/imx6qdl.dtsi
index ed613eb..30e21ee 100644
--- a/arch/arm/boot/dts/imx6qdl.dtsi
+++ b/arch/arm/boot/dts/imx6qdl.dtsi
@@ -185,6 +185,7 @@
cache-level = <2>;
arm,tag-latency = <4 2 3>;
arm,data-latency = <4 2 3>;
+ arm,shared-override;
};
pcie: pcie at 0x01000000 {--
1.9.1