[PATCH 1/1] ARM: dts: imx6qdl.dtsi: add "arm, shared-override" for pl310

Subject: Re: [PATCH 1/1] ARM: dts: imx6qdl.dtsi: add "arm, shared-override" for
pl310

+ Lucas

On Tue, Jun 07, 2016 at 05:39:25PM +0800, Peter Chen wrote:

quoted

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;

Lucas had an objection to the change [1], considering the case that kernel is booted
as non-secure.

Shawn

[1] http://thread.gmane.org/gmane.linux.ports.arm.kernel/471026

Add another Lucas in case he changed his email.

Shawn, do you know what his mean? Why other pl310 parameters can be changed in kernel?

Peter