| From: |
| Andre Przywara <andre.przywara-AT-arm.com> |
| To: |
| Matt Mackall <mpm-AT-selenic.com>, Herbert Xu <herbert-AT-gondor.apana.org.au>, Mark Rutland <mark.rutland-AT-arm.com>, Lorenzo Pieralisi <lorenzo.pieralisi-AT-arm.com>, Sudeep Holla <sudeep.holla-AT-arm.com> |
| Subject: |
| [PATCH v3 0/2] hwrng: Add Arm SMCCC TRNG based driver |
| Date: |
| Mon, 26 Jul 2021 18:56:08 +0100 |
| Message-ID: |
| <20210726175610.3311-1-andre.przywara@arm.com> |
| Cc: |
| linux-crypto-AT-vger.kernel.org, linux-arm-kernel-AT-lists.infradead.org, linux-kernel-AT-vger.kernel.org, Benjamin Herrenschmidt <benh-AT-kernel.crashing.org>, Ard Biesheuvel <ardb-AT-kernel.org>, Mark Brown <broonie-AT-kernel.org>, Will Deacon <will-AT-kernel.org>, Ali Saidi <alisaidi-AT-amazon.com>, Jon Nettleton <jon-AT-solid-run.com> |
| Archive-link: |
| Article |
The "Arm True Random Number Generator Firmware Interface"[1] provides
an SMCCC based interface to a true hardware random number generator.
So far we are using that in arch_get_random_seed(), but it might be
useful to expose the entropy through the /dev/hwrng device as well. This
allows to assess the quality of the implementation, by using "rngtest"
from the rng-tools package, for example.
Patch 1 creates a platform device, triggered by the previous discovery
of the SMCCC TRNG service.
Patch 2 implements a hw_random platform driver, which is instantiated
through this said platform device.
The driver can be loaded as module, or built into the kernel.
[1] https://developer.arm.com/documentation/den0098/latest/
Changelog v2 ... v3:
- split platform device and driver
Changelog v1 ... v2:
- fix building as a module
- de-register device upon exit
- mention module name in Kconfig
Andre Przywara (2):
firmware: smccc: Register smccc_trng platform device
hwrng: Add Arm SMCCC TRNG based driver
drivers/char/hw_random/Kconfig | 14 +++
drivers/char/hw_random/Makefile | 1 +
drivers/char/hw_random/arm_smccc_trng.c | 134 ++++++++++++++++++++++++
drivers/firmware/smccc/smccc.c | 17 +++
4 files changed, 166 insertions(+)
create mode 100644 drivers/char/hw_random/arm_smccc_trng.c
--
2.17.6
