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From: Hrushiraj Gandhi <hrushirajg23@gmail.com>
To: srini@kernel.org
Cc: robh@kernel.org, krzk+dt@kernel.org, conor+dt@kernel.org,
	heiko@sntech.de, devicetree@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org,
	linux-rockchip@lists.infradead.org, linux-kernel@vger.kernel.org,
	Hrushiraj Gandhi <hrushirajg23@gmail.com>
Subject: [PATCH 1/2] dt-bindings: nvmem: rockchip-efuse: add rockchip,efuse-write-enable property
Date: Wed, 15 Jul 2026 16:31:06 +0530	[thread overview]
Message-ID: <20260715110107.409204-2-hrushirajg23@gmail.com> (raw)
In-Reply-To: <20260715110107.409204-1-hrushirajg23@gmail.com>

Add an optional boolean property to explicitly opt in to write (OTP
programming) support. eFuse bits are one-time-programmable and
permanently set once written; write support must therefore not be
enabled by default on arbitrary boards.

Boards that intend to use software-initiated eFuse programming (e.g.
factory key provisioning) must declare this property and must ensure
the required VQPS programming supply (1.8V to 1.98V per RK3399 TRM)
is present and correctly sequenced during writes.

Signed-off-by: Hrushiraj Gandhi <hrushirajg23@gmail.com>
---
 .../devicetree/bindings/nvmem/rockchip-efuse.yaml     | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/Documentation/devicetree/bindings/nvmem/rockchip-efuse.yaml b/Documentation/devicetree/bindings/nvmem/rockchip-efuse.yaml
index b80fd8d1ae5b..8a7195245c84 100644
--- a/Documentation/devicetree/bindings/nvmem/rockchip-efuse.yaml
+++ b/Documentation/devicetree/bindings/nvmem/rockchip-efuse.yaml
@@ -46,6 +46,17 @@ properties:
       this property is defined.
     $ref: /schemas/types.yaml#/definitions/uint32
 
+  rockchip,efuse-write-enable:
+    type: boolean
+    description:
+      Enable write (programming) support for this eFuse block. eFuse bits
+      are one-time-programmable; setting a bit is permanent and cannot be
+      undone. This property must only be set on boards where irreversible
+      OTP programming from software is an intended use case (e.g. factory
+      provisioning), and where the required VQPS programming voltage
+      (1.8V to 1.98V per RK3399 TRM) is guaranteed to be present and
+      correctly sequenced by the board's power design during writes.
+
 required:
   - compatible
   - reg
-- 
2.47.3



  reply	other threads:[~2026-07-15 11:01 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-07-15 11:01 [PATCH 0/2] nvmem: rockchip-efuse: add RK3399 OTP write support Hrushiraj Gandhi
2026-07-15 11:01 ` Hrushiraj Gandhi [this message]
2026-07-15 11:42   ` [PATCH 1/2] dt-bindings: nvmem: rockchip-efuse: add rockchip,efuse-write-enable property Heiko Stübner
2026-07-15 11:01 ` [PATCH 2/2] nvmem: rockchip-efuse: add write support for RK3399 Hrushiraj Gandhi

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