Re: [PATCH v2 1/4] arm64: dts: ti: k3-am65-main: Disable RNG node

From: Jayesh Choudhary
Date: Tue Aug 30 2022 - 05:54:37 EST




On 23/08/22 05:41, Andrew Davis wrote:
The hardware random number generator is used by OP-TEE and is access is
denied to other users with SoC level bus firewalls. Any access to this
device from Linux will result in firewall errors.

We could remove this node, but it is still valid device description,
and it is possible it could be re-enabled in the bootloader if OP-TEE
is not used. So only disable this node for now.

Signed-off-by: Andrew Davis <afd@xxxxxx>
---

Changes from v1:
- Added comment in DT
- Explained why it is only disabled in commit message

arch/arm64/boot/dts/ti/k3-am65-main.dtsi | 1 +
1 file changed, 1 insertion(+)

diff --git a/arch/arm64/boot/dts/ti/k3-am65-main.dtsi b/arch/arm64/boot/dts/ti/k3-am65-main.dtsi
index 8919fede3cd7..b3e714e1abed 100644
--- a/arch/arm64/boot/dts/ti/k3-am65-main.dtsi
+++ b/arch/arm64/boot/dts/ti/k3-am65-main.dtsi
@@ -127,6 +127,7 @@ rng: rng@4e10000 {
reg = <0x0 0x4e10000 0x0 0x7d>;
interrupts = <GIC_SPI 24 IRQ_TYPE_LEVEL_HIGH>;
clocks = <&k3_clks 136 1>;
+ status = "disabled"; /* Used by OP-TEE */
};
};

Reviewed-by: Jayesh Choudhary <j-choudhary@xxxxxx>