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| author | Andre Przywara <andre.przywara@arm.com> | 2021-07-31 23:48:45 +0300 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2021-08-06 14:45:26 +0300 |
| commit | 0888d04b47a165ae8c429c6fe11b3c43f5017f31 (patch) | |
| tree | fb948c4e44df2655c671fa600b17476389bb7d50 /drivers/char/hw_random/Kconfig | |
| parent | b83c2d92be719bf7b1d24ac02aaa53db3991ea58 (diff) | |
| download | linux-0888d04b47a165ae8c429c6fe11b3c43f5017f31.tar.xz | |
hwrng: Add Arm SMCCC TRNG based driver
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.
Add a simple platform driver implementing the hw_random interface.
The corresponding platform device is created by the SMCCC core code,
we just match it here by name and provide a module alias.
Since the firmware takes care about serialisation, this can happily
coexist with the arch_get_random_seed() bits.
[1] https://developer.arm.com/documentation/den0098/latest/
Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'drivers/char/hw_random/Kconfig')
| -rw-r--r-- | drivers/char/hw_random/Kconfig | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig index 3f166c8a4099..239eca4d6805 100644 --- a/drivers/char/hw_random/Kconfig +++ b/drivers/char/hw_random/Kconfig @@ -524,6 +524,20 @@ config HW_RANDOM_XIPHERA To compile this driver as a module, choose M here: the module will be called xiphera-trng. +config HW_RANDOM_ARM_SMCCC_TRNG + tristate "Arm SMCCC TRNG firmware interface support" + depends on HAVE_ARM_SMCCC_DISCOVERY + default HW_RANDOM + help + Say 'Y' to enable the True Random Number Generator driver using + the Arm SMCCC TRNG firmware interface. This reads entropy from + higher exception levels (firmware, hypervisor). Uses SMCCC for + communicating with the firmware: + https://developer.arm.com/documentation/den0098/latest/ + + To compile this driver as a module, choose M here: the + module will be called arm_smccc_trng. + endif # HW_RANDOM config UML_RANDOM |