linux-kernel - [PATCH v3 09/19] dt-bindings: nvmem: microchip-otpc: Add required clocks

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20260120154502.1280938-3-ada@thorsis.com>
Date: Tue, 20 Jan 2026 16:44:43 +0100
From: Alexander Dahl <ada@...rsis.com>
To: Claudiu Beznea <claudiu.beznea@...on.dev>
Cc: Nicolas Ferre <nicolas.ferre@...rochip.com>,
	Alexandre Belloni <alexandre.belloni@...tlin.com>,
	Ryan Wanner <ryan.wanner@...rochip.com>,
	linux-arm-kernel@...ts.infradead.org,
	devicetree@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	linux-clk@...r.kernel.org,
	Srinivas Kandagatla <srini@...nel.org>,
	Rob Herring <robh@...nel.org>,
	Krzysztof Kozlowski <krzk+dt@...nel.org>,
	Conor Dooley <conor+dt@...nel.org>
Subject: [PATCH v3 09/19] dt-bindings: nvmem: microchip-otpc: Add required clocks

The OTPC requires both the peripheral clock through PMC and the main RC
oscillator.  Seemed to work without explicitly enabling those clocks on
sama7g5 before, but did not on sam9x60.

Older datasheets were not clear and explicit about this, but recent are,
e.g. SAMA7G5 series datasheet (DS60001765B),
section 30.4.1 Power Management:

> The OTPC is clocked through the Power Management Controller (PMC).
> The user must power on the main RC oscillator and enable the
> peripheral clock of the OTPC prior to reading or writing the OTP
> memory.

Link: https://lore.kernel.org/linux-clk/ec34efc2-2051-4b8a-b5d8-6e2fd5e08c28@microchip.com/T/#u
Signed-off-by: Alexander Dahl <ada@...rsis.com>
---

Notes:
    v3:
    - Removed clock-names (led to confusion, and not used by the driver anyways)
    - Removed redundant example
    
    v2:
    - new patch, not present in v1

 .../devicetree/bindings/nvmem/microchip,sama7g5-otpc.yaml | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/Documentation/devicetree/bindings/nvmem/microchip,sama7g5-otpc.yaml b/Documentation/devicetree/bindings/nvmem/microchip,sama7g5-otpc.yaml
index 9a7aaf64eef32..847dfb67c6b72 100644
--- a/Documentation/devicetree/bindings/nvmem/microchip,sama7g5-otpc.yaml
+++ b/Documentation/devicetree/bindings/nvmem/microchip,sama7g5-otpc.yaml
@@ -29,6 +29,11 @@ properties:
   reg:
     maxItems: 1
 
+  clocks:
+    items:
+      - description: main rc oscillator
+      - description: otpc peripheral clock
+
 required:
   - compatible
   - reg
@@ -37,6 +42,8 @@ unevaluatedProperties: false
 
 examples:
   - |
+    #include <dt-bindings/clock/at91.h>
+    #include <dt-bindings/clock/microchip,sama7g5-pmc.h>
     #include <dt-bindings/nvmem/microchip,sama7g5-otpc.h>
 
     otpc: efuse@...00000 {
@@ -44,6 +51,7 @@ examples:
         reg = <0xe8c00000 0xec>;
         #address-cells = <1>;
         #size-cells = <1>;
+        clocks = <&pmc PMC_TYPE_CORE SAMA7G5_PMC_MAIN_RC>, <&pmc PMC_TYPE_PERIPHERAL 67>;
 
         temperature_calib: calib@1 {
             reg = <OTP_PKT(1) 76>;
-- 
2.47.3