linux-kernel - [PATCH v3 0/3] m68k: coldfire: Add RNG support and const qualifiers for MCF54418

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-next>] [day] [month] [year] [list]

Message-Id: <20251124-b4-m5441x-add-rng-support-v3-0-f447251dad27@yoseli.org>
Date: Mon, 24 Nov 2025 14:04:05 +0100
From: Jean-Michel Hautbois <jeanmichel.hautbois@...eli.org>
To: Greg Ungerer <gerg@...ux-m68k.org>, 
 Geert Uytterhoeven <geert@...ux-m68k.org>, 
 Olivia Mackall <olivia@...enic.com>, 
 Herbert Xu <herbert@...dor.apana.org.au>, Shawn Guo <shawnguo@...nel.org>, 
 Sascha Hauer <s.hauer@...gutronix.de>, 
 Pengutronix Kernel Team <kernel@...gutronix.de>, 
 Fabio Estevam <festevam@...il.com>
Cc: linux-m68k@...ts.linux-m68k.org, linux-kernel@...r.kernel.org, 
 linux-crypto@...r.kernel.org, imx@...ts.linux.dev, 
 linux-arm-kernel@...ts.infradead.org, 
 Jean-Michel Hautbois <jeanmichel.hautbois@...eli.org>, 
 Frank Li <Frank.Li@....com>
Subject: [PATCH v3 0/3] m68k: coldfire: Add RNG support and const
 qualifiers for MCF54418

This series adds support for the MCF54418 hardware random number generator
(RNGB) and improves type safety for platform device resources.

The MCF54418 contains an RNGB hardware block compatible with the imx-rngc
driver. This series enables its use by:
- Adding platform device registration for the RNG hardware
- Enabling the clock at platform initialization
- Making the imx-rngc driver compatible with Coldfire's always-on clock
model using devm_clk_get_optional()

Additionally, following Frank Li's suggestion, all static resource array
in arch/m68k/coldfire/device.c are marked const, moving them to read-only
memory and aligning with kernel API expectations.

Testing on DLC Next board shows:
- Hardware RNG throughput: 26 MB/s
- FIPS 140-2 quality: 0.2% failure rate (rng-tools)
- Boot time improvement: CRNG initialization 7 seconds faster

Signed-off-by: Jean-Michel Hautbois <jeanmichel.hautbois@...eli.org>
---
Changes in v3:
- Depend on COLDFIRE is enough
- Split the clock change in a dedicated commit
- Link to v2: https://lore.kernel.org/r/20251107-b4-m5441x-add-rng-support-v2-0-f91d685832b9@yoseli.org

Changes in v2:
- Split const qualifier changes into a separate patch as suggested by
Frank Li
- Mark all resource arrays (including RNG) as const in device.c
- No functional changes to RNG implementation

---
Jean-Michel Hautbois (3):
      m68k: coldfire: Mark platform device resource arrays as const
      hwrng: imx-rngc: Use optional clock
      m68k: coldfire: Add RNG support for MCF54418

 arch/m68k/coldfire/device.c       | 52 ++++++++++++++++++++++++++++++---------
 arch/m68k/coldfire/m5441x.c       |  2 +-
 arch/m68k/include/asm/m5441xsim.h |  9 +++++++
 drivers/char/hw_random/Kconfig    |  3 ++-
 drivers/char/hw_random/imx-rngc.c |  9 ++++++-
 5 files changed, 60 insertions(+), 15 deletions(-)
---
base-commit: ac3fd01e4c1efce8f2c054cdeb2ddd2fc0fb150d
change-id: 20251107-b4-m5441x-add-rng-support-0fdb8d40210a

Best regards,
-- 
Jean-Michel Hautbois <jeanmichel.hautbois@...eli.org>