Add Vorago VA416x0 hardware TRNG support

[dgarske]

Add Vorago VA416x0 hardware TRNG support

Adds a wc_GenerateSeed() implementation for the Vorago VA416x0 (Cortex-M4F) on-chip True Random Number Generator, gated by a new WOLFSSL_VA416X0_TRNG build macro. The TRNG is an Arm CryptoCell-style entropy block (192-bit EHR, ring-oscillator source, Von-Neumann / CRNGT / autocorrelation health tests), accessed register-only via the VA416xx SDK (va416xx.h); no SDK HAL driver exists for it.

Because the TRNG produces only ~1.25 kb/s of entropy, it is used as a seed source for the SP800-90A Hash-DRBG (keep HAVE_HASHDRBG on), not for bulk generation.

Usage

#define WOLFSSL_VA416X0_TRNG   /* in user_settings.h; needs va416xx.h on the include path */

Optional tuning defines (with defaults): WOLFSSL_VA416X0_TRNG_SAMPLE_CNT (1000), WOLFSSL_VA416X0_TRNG_MAX_RETRY (10), WOLFSSL_VA416X0_TRNG_TIMEOUT (1000000).

Notes

• Releases the TRNG from PERIPHERAL_RESET (active-low) before use; without this, all TRNG register writes are silently ignored.
• Health tests stay enabled: a health-test error re-collects up to MAX_RETRY times; a per-block poll cap returns RNG_FAILURE_E instead of hanging.
• Seed material is scrubbed from the stack with ForceZero().

Testing

Validated on the VA416XX EVK (J-Link/SWD) via the wolfBoot test-app with WOLFCRYPT_TEST=1: wolfCrypt RANDOM test passed! (DRBG instantiate + SP800-90A health checks), alongside the SHA and ECC self-tests.

[Copilot]

Pull request overview

Note

Copilot was unable to run its full agentic suite in this review.

Adds a new hardware-entropy backend for Vorago VA416x0 by implementing wc_GenerateSeed() using the on-chip TRNG, gated behind WOLFSSL_VA416X0_TRNG, and documents the new build macro.

Changes:

• Add a VA416x0 TRNG-based wc_GenerateSeed() implementation with retry/timeout behavior and stack scrubbing.
• Document the new WOLFSSL_VA416X0_TRNG macro in random.c and register it in .wolfssl_known_macro_extras.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 4 comments.

File	Description
wolfcrypt/src/random.c	Adds the VA416x0 TRNG seed generator implementation and documents the new macro/tuning defines.
.wolfssl_known_macro_extras	Adds WOLFSSL_VA416X0_TRNG to the known macro list (and also removes two existing macros in the same hunk).

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[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

[github-actions]

MemBrowse Memory Report

No memory changes detected for:

• gcc-arm-cortex-m0plus
• gcc-arm-cortex-m3
• gcc-arm-cortex-m4
• gcc-arm-cortex-m4-baremetal
• gcc-arm-cortex-m4-crypto-only
• gcc-arm-cortex-m4-dtls13
• gcc-arm-cortex-m4-min-ecc
• gcc-arm-cortex-m4-openssl-compat
• gcc-arm-cortex-m4-pkcs7
• gcc-arm-cortex-m4-pq
• gcc-arm-cortex-m4-rsa-only
• gcc-arm-cortex-m4-sp-math
• gcc-arm-cortex-m4-tls12
• gcc-arm-cortex-m4-tls13
• gcc-arm-cortex-m7
• gcc-arm-cortex-m7-pq
• gcc-arm-cortex-m7-tls13
• linuxkm-pie
• linuxkm-standard
• stm32-sim-stm32h753

[github-actions]

retest this please

[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated no new comments.