diff options
| author | Sughosh Ganu | 2022-07-22 21:32:04 +0530 |
|---|---|---|
| committer | Ilias Apalodimas | 2022-08-02 23:50:02 +0300 |
| commit | e67ffb5aa5ab03a89305f4575ad3142486f9a306 (patch) | |
| tree | 624c26edcc914c27bcdd0a8a04e4490995572d84 /drivers | |
| parent | 5d98329196daaf624c39304aec1397d6363b3e72 (diff) | |
tpm: rng: Add driver model interface for TPM RNG device
The TPM device has a builtin random number generator(RNG)
functionality. Expose the RNG functions of the TPM device to the
driver model so that they can be used by the EFI_RNG_PROTOCOL if the
protocol is installed.
Also change the function arguments and return type of the random
number functions to comply with the driver model api.
Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/rng/Kconfig | 9 | ||||
| -rw-r--r-- | drivers/rng/Makefile | 1 | ||||
| -rw-r--r-- | drivers/rng/tpm_rng.c | 23 |
3 files changed, 33 insertions, 0 deletions
diff --git a/drivers/rng/Kconfig b/drivers/rng/Kconfig index 21a9ff01954..16143681da6 100644 --- a/drivers/rng/Kconfig +++ b/drivers/rng/Kconfig @@ -74,4 +74,13 @@ config RNG_SMCCC_TRNG Enable random number generator for platforms that support Arm SMCCC TRNG interface. +config TPM_RNG + bool "Enable random number generator on TPM device" + depends on TPM + default y + help + The TPM device has an inbuilt random number generator + functionality. Enable random number generator on TPM + devices. + endif diff --git a/drivers/rng/Makefile b/drivers/rng/Makefile index 2494717d7c7..78f61051acf 100644 --- a/drivers/rng/Makefile +++ b/drivers/rng/Makefile @@ -13,3 +13,4 @@ obj-$(CONFIG_RNG_STM32MP1) += stm32mp1_rng.o obj-$(CONFIG_RNG_ROCKCHIP) += rockchip_rng.o obj-$(CONFIG_RNG_IPROC200) += iproc_rng200.o obj-$(CONFIG_RNG_SMCCC_TRNG) += smccc_trng.o +obj-$(CONFIG_TPM_RNG) += tpm_rng.o diff --git a/drivers/rng/tpm_rng.c b/drivers/rng/tpm_rng.c new file mode 100644 index 00000000000..1a5e9e2e4b4 --- /dev/null +++ b/drivers/rng/tpm_rng.c @@ -0,0 +1,23 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 2022, Linaro Limited + */ + +#include <dm.h> +#include <rng.h> +#include <tpm_api.h> + +static int rng_tpm_random_read(struct udevice *dev, void *data, size_t count) +{ + return tpm_get_random(dev_get_parent(dev), data, count); +} + +static const struct dm_rng_ops tpm_rng_ops = { + .read = rng_tpm_random_read, +}; + +U_BOOT_DRIVER(tpm_rng) = { + .name = "tpm-rng", + .id = UCLASS_RNG, + .ops = &tpm_rng_ops, +}; |