On Wed, 20 Jul 2022 at 15:30, Sughosh Ganu sughosh.ganu@linaro.org wrote:

From: Simon Glass sjg@chromium.org

These functions should really be available outside the TPM code, so that other callers can find out which version the TPM is. Rename them to have a tpm_ prefix() and add them to the header file.

Signed-off-by: Simon Glass sjg@chromium.org

Changes since V6: None

include/tpm_api.h | 10 ++++++ lib/tpm_api.c | 92 +++++++++++++++++++++-------------------------- 2 files changed, 51 insertions(+), 51 deletions(-)

diff --git a/include/tpm_api.h b/include/tpm_api.h index ef45b43a8f..11aa14eb79 100644 --- a/include/tpm_api.h +++ b/include/tpm_api.h @@ -319,4 +319,14 @@ u32 tpm_write_lock(struct udevice *dev, u32 index); */ u32 tpm_resume(struct udevice *dev);

+static inline bool tpm_is_v1(struct udevice *dev) +{

•   return IS_ENABLED(CONFIG_TPM_V1) && tpm_get_version(dev) == TPM_V1;
  

+}

+static inline bool tpm_is_v2(struct udevice *dev) +{

•   return IS_ENABLED(CONFIG_TPM_V2) && tpm_get_version(dev) == TPM_V2;
  

+}

#endif /* __TPM_API_H */ diff --git a/lib/tpm_api.c b/lib/tpm_api.c index 4c662640a9..4ac4612c81 100644 --- a/lib/tpm_api.c +++ b/lib/tpm_api.c @@ -11,21 +11,11 @@ #include <tpm-v2.h> #include <tpm_api.h>

-static bool is_tpm1(struct udevice *dev) -{

•   return IS_ENABLED(CONFIG_TPM_V1) && tpm_get_version(dev) == TPM_V1;
  

-}

-static bool is_tpm2(struct udevice *dev) -{

•   return IS_ENABLED(CONFIG_TPM_V2) && tpm_get_version(dev) == TPM_V2;
  

-}

u32 tpm_startup(struct udevice *dev, enum tpm_startup_type mode) {

•   if (is_tpm1(dev)) {
  

•   if (tpm_is_v1(dev)) {
            return tpm1_startup(dev, mode);
  

•   } else if (is_tpm2(dev)) {
  

•   } else if (tpm_is_v2(dev)) {
            enum tpm2_startup_types type;
  
            switch (mode) {
  

@@ -47,9 +37,9 @@ u32 tpm_startup(struct udevice *dev, enum tpm_startup_type mode)

u32 tpm_resume(struct udevice *dev) {

•   if (is_tpm1(dev))
  

•   if (tpm_is_v1(dev))
            return tpm1_startup(dev, TPM_ST_STATE);
  

•   else if (is_tpm2(dev))
  

•   else if (tpm_is_v2(dev))
            return tpm2_startup(dev, TPM2_SU_STATE);
    else
            return -ENOSYS;
  

@@ -57,9 +47,9 @@ u32 tpm_resume(struct udevice *dev)

u32 tpm_self_test_full(struct udevice *dev) {

•   if (is_tpm1(dev))
  

•   if (tpm_is_v1(dev))
            return tpm1_self_test_full(dev);
  

•   else if (is_tpm2(dev))
  

•   else if (tpm_is_v2(dev))
            return tpm2_self_test(dev, TPMI_YES);
    else
            return -ENOSYS;
  

@@ -67,9 +57,9 @@ u32 tpm_self_test_full(struct udevice *dev)

u32 tpm_continue_self_test(struct udevice *dev) {

•   if (is_tpm1(dev))
  

•   if (tpm_is_v1(dev))
            return tpm1_continue_self_test(dev);
  

•   else if (is_tpm2(dev))
  

•   else if (tpm_is_v2(dev))
            return tpm2_self_test(dev, TPMI_NO);
    else
            return -ENOSYS;
  

@@ -86,7 +76,7 @@ u32 tpm_clear_and_reenable(struct udevice *dev) return ret; }

•   if (is_tpm1(dev)) {
  

•   if (tpm_is_v1(dev)) {
            ret = tpm1_physical_enable(dev);
            if (ret != TPM_SUCCESS) {
                    log_err("TPM: Can't set enabled state\n");
  

@@ -105,9 +95,9 @@ u32 tpm_clear_and_reenable(struct udevice *dev)

u32 tpm_nv_enable_locking(struct udevice *dev) {

•   if (is_tpm1(dev))
  

•   if (tpm_is_v1(dev))
            return tpm1_nv_define_space(dev, TPM_NV_INDEX_LOCK, 0, 0);
  

•   else if (is_tpm2(dev))
  

•   else if (tpm_is_v2(dev))
            return -ENOSYS;
    else
            return -ENOSYS;
  

@@ -115,9 +105,9 @@ u32 tpm_nv_enable_locking(struct udevice *dev)

u32 tpm_nv_read_value(struct udevice *dev, u32 index, void *data, u32 count) {

•   if (is_tpm1(dev))
  

•   if (tpm_is_v1(dev))
            return tpm1_nv_read_value(dev, index, data, count);
  

•   else if (is_tpm2(dev))
  

•   else if (tpm_is_v2(dev))
            return tpm2_nv_read_value(dev, index, data, count);
    else
            return -ENOSYS;
  

@@ -126,9 +116,9 @@ u32 tpm_nv_read_value(struct udevice *dev, u32 index, void *data, u32 count) u32 tpm_nv_write_value(struct udevice *dev, u32 index, const void *data, u32 count) {

•   if (is_tpm1(dev))
  

•   if (tpm_is_v1(dev))
            return tpm1_nv_write_value(dev, index, data, count);
  

•   else if (is_tpm2(dev))
  

•   else if (tpm_is_v2(dev))
            return tpm2_nv_write_value(dev, index, data, count);
    else
            return -ENOSYS;
  

@@ -141,9 +131,9 @@ u32 tpm_set_global_lock(struct udevice *dev)

u32 tpm_write_lock(struct udevice *dev, u32 index) {

•   if (is_tpm1(dev))
  

•   if (tpm_is_v1(dev))
            return -ENOSYS;
  

•   else if (is_tpm2(dev))
  

•   else if (tpm_is_v2(dev))
            return tpm2_write_lock(dev, index);
    else
            return -ENOSYS;
  

@@ -152,9 +142,9 @@ u32 tpm_write_lock(struct udevice *dev, u32 index) u32 tpm_pcr_extend(struct udevice *dev, u32 index, const void *in_digest, void *out_digest) {

•   if (is_tpm1(dev))
  

•   if (tpm_is_v1(dev))
            return tpm1_extend(dev, index, in_digest, out_digest);
  

•   else if (is_tpm2(dev))
  

•   else if (tpm_is_v2(dev))
            return tpm2_pcr_extend(dev, index, TPM2_ALG_SHA256, in_digest,
                                   TPM2_DIGEST_LEN);
    else
  

@@ -163,9 +153,9 @@ u32 tpm_pcr_extend(struct udevice *dev, u32 index, const void *in_digest,

u32 tpm_pcr_read(struct udevice *dev, u32 index, void *data, size_t count) {

•   if (is_tpm1(dev))
  

•   if (tpm_is_v1(dev))
            return tpm1_pcr_read(dev, index, data, count);
  

•   else if (is_tpm2(dev))
  

•   else if (tpm_is_v2(dev))
            return -ENOSYS;
    else
            return -ENOSYS;
  

@@ -173,14 +163,14 @@ u32 tpm_pcr_read(struct udevice *dev, u32 index, void *data, size_t count)

u32 tpm_tsc_physical_presence(struct udevice *dev, u16 presence) {

•   if (is_tpm1(dev))
  

•   if (tpm_is_v1(dev))
            return tpm1_tsc_physical_presence(dev, presence);
  
    /*
     * Nothing to do on TPM2 for this; use platform hierarchy availability
     * instead.
     */
  

•   else if (is_tpm2(dev))
  

•   else if (tpm_is_v2(dev))
            return 0;
    else
            return -ENOSYS;
  

@@ -188,11 +178,11 @@ u32 tpm_tsc_physical_presence(struct udevice *dev, u16 presence)

u32 tpm_finalise_physical_presence(struct udevice *dev) {

•   if (is_tpm1(dev))
  

•   if (tpm_is_v1(dev))
            return tpm1_finalise_physical_presence(dev);
  
    /* Nothing needs to be done with tpm2 */
  

•   else if (is_tpm2(dev))
  

•   else if (tpm_is_v2(dev))
            return 0;
    else
            return -ENOSYS;
  

@@ -200,9 +190,9 @@ u32 tpm_finalise_physical_presence(struct udevice *dev)

u32 tpm_read_pubek(struct udevice *dev, void *data, size_t count) {

•   if (is_tpm1(dev))
  

•   if (tpm_is_v1(dev))
            return tpm1_read_pubek(dev, data, count);
  

•   else if (is_tpm2(dev))
  

•   else if (tpm_is_v2(dev))
            return -ENOSYS; /* not implemented yet */
    else
            return -ENOSYS;
  

@@ -210,9 +200,9 @@ u32 tpm_read_pubek(struct udevice *dev, void *data, size_t count)

u32 tpm_force_clear(struct udevice *dev) {

•   if (is_tpm1(dev))
  

•   if (tpm_is_v1(dev))
            return tpm1_force_clear(dev);
  

•   else if (is_tpm2(dev))
  

•   else if (tpm_is_v2(dev))
            return tpm2_clear(dev, TPM2_RH_PLATFORM, NULL, 0);
    else
            return -ENOSYS;
  

@@ -220,11 +210,11 @@ u32 tpm_force_clear(struct udevice *dev)

u32 tpm_physical_enable(struct udevice *dev) {

•   if (is_tpm1(dev))
  

•   if (tpm_is_v1(dev))
            return tpm1_physical_enable(dev);
  
    /* Nothing needs to be done with tpm2 */
  

•   else if (is_tpm2(dev))
  

•   else if (tpm_is_v2(dev))
            return 0;
    else
            return -ENOSYS;
  

@@ -232,11 +222,11 @@ u32 tpm_physical_enable(struct udevice *dev)

u32 tpm_physical_disable(struct udevice *dev) {

•   if (is_tpm1(dev))
  

•   if (tpm_is_v1(dev))
            return tpm1_physical_disable(dev);
  
    /* Nothing needs to be done with tpm2 */
  

•   else if (is_tpm2(dev))
  

•   else if (tpm_is_v2(dev))
            return 0;
    else
            return -ENOSYS;
  

@@ -244,10 +234,10 @@ u32 tpm_physical_disable(struct udevice *dev)

u32 tpm_physical_set_deactivated(struct udevice *dev, u8 state) {

•   if (is_tpm1(dev))
  

•   if (tpm_is_v1(dev))
            return tpm1_physical_set_deactivated(dev, state);
    /* Nothing needs to be done with tpm2 */
  

•   else if (is_tpm2(dev))
  

•   else if (tpm_is_v2(dev))
            return 0;
    else
            return -ENOSYS;
  

@@ -256,9 +246,9 @@ u32 tpm_physical_set_deactivated(struct udevice *dev, u8 state) u32 tpm_get_capability(struct udevice *dev, u32 cap_area, u32 sub_cap, void *cap, size_t count) {

•   if (is_tpm1(dev))
  

•   if (tpm_is_v1(dev))
            return tpm1_get_capability(dev, cap_area, sub_cap, cap, count);
  

•   else if (is_tpm2(dev))
  

•   else if (tpm_is_v2(dev))
            return tpm2_get_capability(dev, cap_area, sub_cap, cap, count);
    else
            return -ENOSYS;
  

@@ -266,9 +256,9 @@ u32 tpm_get_capability(struct udevice *dev, u32 cap_area, u32 sub_cap,

u32 tpm_get_permissions(struct udevice *dev, u32 index, u32 *perm) {

•   if (is_tpm1(dev))
  

•   if (tpm_is_v1(dev))
            return tpm1_get_permissions(dev, index, perm);
  

•   else if (is_tpm2(dev))
  

•   else if (tpm_is_v2(dev))
            return -ENOSYS; /* not implemented yet */
    else
            return -ENOSYS;
  

@@ -276,9 +266,9 @@ u32 tpm_get_permissions(struct udevice *dev, u32 index, u32 *perm)

u32 tpm_get_random(struct udevice *dev, void *data, u32 count) {

•   if (is_tpm1(dev))
  

•   if (tpm_is_v1(dev))
            return tpm1_get_random(dev, data, count);
  

•   else if (is_tpm2(dev))
  

•   else if (tpm_is_v2(dev))
            return -ENOSYS; /* not implemented yet */
    else
            return -ENOSYS;
  

-- 2.34.1

Reviewed-by: Ilias Apalodimas ilias.apalodimas@linaro.org

On Wed, 20 Jul 2022 at 15:30, Sughosh Ganu sughosh.ganu@linaro.org wrote:

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

Changes since V6:

• Remove the changes made in tpm-v[12].c to return -EIO instead of TPM_LIB_ERROR as suggested by Simon

drivers/rng/Kconfig | 9 +++++++++ drivers/rng/Makefile | 1 + drivers/rng/tpm_rng.c | 23 +++++++++++++++++++++++ lib/Kconfig | 1 + lib/tpm_api.c | 6 +++--- 5 files changed, 37 insertions(+), 3 deletions(-) create mode 100644 drivers/rng/tpm_rng.c

diff --git a/drivers/rng/Kconfig b/drivers/rng/Kconfig index 21a9ff0195..16143681da 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

We could probably skip the extra Kconfig and just look for a TPM. But let's leave it as is for now, it's an easy change if we ever want that

diff --git a/drivers/rng/Makefile b/drivers/rng/Makefile index 2494717d7c..78f61051ac 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 0000000000..1a5e9e2e4b --- /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,
  

+}; diff --git a/lib/Kconfig b/lib/Kconfig index 7dd777b56a..e888c29245 100644 --- a/lib/Kconfig +++ b/lib/Kconfig @@ -360,6 +360,7 @@ source lib/crypt/Kconfig config TPM bool "Trusted Platform Module (TPM) Support" depends on DM

•   imply DM_RNG
    help
      This enables support for TPMs which can be used to provide security
      features for your board. The TPM can be connected via LPC or I2C
  

diff --git a/lib/tpm_api.c b/lib/tpm_api.c index 4ac4612c81..032f383ca0 100644 --- a/lib/tpm_api.c +++ b/lib/tpm_api.c @@ -269,7 +269,7 @@ u32 tpm_get_random(struct udevice *dev, void *data, u32 count) if (tpm_is_v1(dev)) return tpm1_get_random(dev, data, count); else if (tpm_is_v2(dev))

•           return -ENOSYS; /* not implemented yet */
  

•   else
  

•           return -ENOSYS;
  

•           return tpm2_get_random(dev, data, count);
  

•   return -ENOSYS;
  

}

2.34.1

Reviewed-by: Ilias Apalodimas ilias.apalodimas@linaro.org

On Wed, 20 Jul 2022 at 15:30, Sughosh Ganu sughosh.ganu@linaro.org wrote:

The TPM device comes with the random number generator(RNG) functionality which is built into the TPM device. Add logic to add the RNG child device in the TPM uclass post probe callback.

The RNG device can then be used to pass a set of random bytes to the linux kernel, need for address space randomisation through the EFI_RNG_PROTOCOL interface.

Signed-off-by: Sughosh Ganu sughosh.ganu@linaro.org

Changes since V6: None

drivers/tpm/tpm-uclass.c | 37 +++++++++++++++++++++++++++++++++---- 1 file changed, 33 insertions(+), 4 deletions(-)

diff --git a/drivers/tpm/tpm-uclass.c b/drivers/tpm/tpm-uclass.c index f67fe1019b..e1f1ef01e1 100644 --- a/drivers/tpm/tpm-uclass.c +++ b/drivers/tpm/tpm-uclass.c @@ -11,10 +11,15 @@ #include <log.h> #include <linux/delay.h> #include <linux/unaligned/be_byteshift.h> +#include <tpm_api.h> #include <tpm-v1.h> #include <tpm-v2.h> #include "tpm_internal.h"

+#include <dm/lists.h>

+#define TPM_RNG_DRV_NAME "tpm-rng"

int tpm_open(struct udevice *dev) { struct tpm_ops *ops = tpm_get_ops(dev); @@ -136,12 +141,36 @@ int tpm_xfer(struct udevice *dev, const uint8_t *sendbuf, size_t send_size, return 0; }

+static int tpm_uclass_post_probe(struct udevice *dev) +{

•   int ret;
  

•   const char *drv = TPM_RNG_DRV_NAME;
  

•   struct udevice *child;
  

•   if (CONFIG_IS_ENABLED(TPM_RNG)) {
  

•           ret = device_find_first_child_by_uclass(dev, UCLASS_RNG,
  

•                                                   &child);
  

•           if (ret != -ENODEV) {
  

•                   log_debug("RNG child already added to the TPM device\n");
  

•                   return ret;
  

•           }
  

•           ret = device_bind_driver(dev, drv, "tpm-rng0", &child);
  

•           if (ret)
  

•                   return log_msg_ret("bind", ret);
  

•   }
  

•   return 0;
  

+}

UCLASS_DRIVER(tpm) = {

•   .id             = UCLASS_TPM,
  

•   .name           = "tpm",
  

•   .flags          = DM_UC_FLAG_SEQ_ALIAS,
  

•   .id                     = UCLASS_TPM,
  

•   .name                   = "tpm",
  

•   .flags                  = DM_UC_FLAG_SEQ_ALIAS,
  

#if CONFIG_IS_ENABLED(OF_REAL)

•   .post_bind      = dm_scan_fdt_dev,
  

•   .post_bind              = dm_scan_fdt_dev,
  

#endif

•   .post_probe             = tpm_uclass_post_probe,
    .per_device_auto        = sizeof(struct tpm_chip_priv),
  

};

2.34.1

Simon can you please ACK this ? Looks good to me

Reviewed-by: Ilias Apalodimas ilias.apalodimas@linaro.org

Hi Simon,

On Fri, 22 Jul 2022 at 12:00, Simon Glass sjg@chromium.org wrote:

Hi Sughosh,

On Wed, 20 Jul 2022 at 06:30, Sughosh Ganu sughosh.ganu@linaro.org wrote:

...

The TPM device comes with the random number generator(RNG) functionality which is built into the TPM device. Add logic to add the RNG child device in the TPM uclass post probe callback.

The RNG device can then be used to pass a set of random bytes to the linux kernel, need for address space randomisation through the EFI_RNG_PROTOCOL interface.

Ilias has asked me to review this patch again.

I don't want my review tag on it since it is not correct, so far as driver model / device tree go. But I have no objection to it going in since my understanding is we can disable TPM_RNG later as needed.

Yes you can

I prefer to have some acknowledgement of the previous discussion, e.g.:

Sure

No compatible string is provided because this is not available in the binding defined by Linux. If multiple rand devices are in the system, then some method of selecting them (other than device tree) will need to be used, or a binding will need to be added.

since I cannot imagine people remembering to look up the previous version in patchwork.

Comment in the code or commit message? I'd prefer adding it as a comment

But if you don't want that, then that's fine.

No I am fine that makes sense. What I was looking for was basically your acknowledgement that we are going to pick this up.

Shall I carry it on the TPM tree?

Thanks /Ilias

...

Signed-off-by: Sughosh Ganu sughosh.ganu@linaro.org

Changes since V6: None

drivers/tpm/tpm-uclass.c | 37 +++++++++++++++++++++++++++++++++---- 1 file changed, 33 insertions(+), 4 deletions(-)

diff --git a/drivers/tpm/tpm-uclass.c b/drivers/tpm/tpm-uclass.c index f67fe1019b..e1f1ef01e1 100644 --- a/drivers/tpm/tpm-uclass.c +++ b/drivers/tpm/tpm-uclass.c @@ -11,10 +11,15 @@ #include <log.h> #include <linux/delay.h> #include <linux/unaligned/be_byteshift.h> +#include <tpm_api.h> #include <tpm-v1.h> #include <tpm-v2.h> #include "tpm_internal.h"

+#include <dm/lists.h>

BTW this should be above the previous header.

...

+#define TPM_RNG_DRV_NAME "tpm-rng"

int tpm_open(struct udevice *dev) { struct tpm_ops *ops = tpm_get_ops(dev); @@ -136,12 +141,36 @@ int tpm_xfer(struct udevice *dev, const uint8_t *sendbuf, size_t send_size, return 0; }

+static int tpm_uclass_post_probe(struct udevice *dev) +{

•   int ret;
  

•   const char *drv = TPM_RNG_DRV_NAME;
  

•   struct udevice *child;
  

•   if (CONFIG_IS_ENABLED(TPM_RNG)) {
  

•           ret = device_find_first_child_by_uclass(dev, UCLASS_RNG,
  

•                                                   &child);
  

•           if (ret != -ENODEV) {
  

•                   log_debug("RNG child already added to the TPM device\n");
  

•                   return ret;
  

•           }
  

•           ret = device_bind_driver(dev, drv, "tpm-rng0", &child);
  

If this does get re-issued, I think this could just use TPM_RNG_DRV_NAME directory.

...

•           if (ret)
  

•                   return log_msg_ret("bind", ret);
  

•   }
  

•   return 0;
  

+}

UCLASS_DRIVER(tpm) = {

•   .id             = UCLASS_TPM,
  

•   .name           = "tpm",
  

•   .flags          = DM_UC_FLAG_SEQ_ALIAS,
  

•   .id                     = UCLASS_TPM,
  

•   .name                   = "tpm",
  

•   .flags                  = DM_UC_FLAG_SEQ_ALIAS,
  

#if CONFIG_IS_ENABLED(OF_REAL)

•   .post_bind      = dm_scan_fdt_dev,
  

•   .post_bind              = dm_scan_fdt_dev,
  

#endif

•   .post_probe             = tpm_uclass_post_probe,
    .per_device_auto        = sizeof(struct tpm_chip_priv),
  

};

2.34.1

Regards, Simon

Hi Sughosh,

This is missing the r-b tags from Simon and myself. Once I finish up the review, can you re-send the series with the missing tags?

Thanks /Ilias

On Wed, 20 Jul 2022 at 15:30, Sughosh Ganu sughosh.ganu@linaro.org wrote:

Use a statically allocated buffer on stack instead of using malloc for reading the random bytes. Using a local array is faster than allocating heap memory on every initiation of the command.

Signed-off-by: Sughosh Ganu sughosh.ganu@linaro.org

Changes since V6: None

cmd/rng.c | 17 +++++++---------- 1 file changed, 7 insertions(+), 10 deletions(-)

diff --git a/cmd/rng.c b/cmd/rng.c index 2ddf27545f..81a23964b8 100644 --- a/cmd/rng.c +++ b/cmd/rng.c @@ -14,9 +14,9 @@ static int do_rng(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]) { size_t n;

•   struct udevice *dev;
  

•   void *buf;
  

•   u8 buf[64];
    int devnum;
  

•   struct udevice *dev;
    int ret = CMD_RET_SUCCESS;
  
    switch (argc) {
  

@@ -41,11 +41,10 @@ static int do_rng(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]) return CMD_RET_FAILURE; }

•   buf = malloc(n);
  

•   if (!buf) {
  

•           printf("Out of memory\n");
  

•           return CMD_RET_FAILURE;
  

•   }
  

•   if (!n)
  

•           return 0;
  

•   n = min(n, sizeof(buf));
  
    if (dm_rng_read(dev, buf, n)) {
            printf("Reading RNG failed\n");
  

@@ -54,15 +53,13 @@ static int do_rng(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[]) print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, buf, n); }

•   free(buf);
  

•   return ret;
  

}

#ifdef CONFIG_SYS_LONGHELP static char rng_help_text[] = "[dev [n]]\n"

•   "  - print n random bytes read from dev\n";
  

•   "  - print n random bytes(max 64) read from dev\n";
  

#endif

U_BOOT_CMD(

2.34.1

On Wed, 20 Jul 2022 at 15:30, Sughosh Ganu sughosh.ganu@linaro.org wrote:

The 'rng' command dumps a number of random bytes on the console. Add a set of tests for the 'rng' command. The test function performs basic sanity testing of the command.

Since a unit test is being added for the command, enable it by default in the sandbox platforms.

Signed-off-by: Sughosh Ganu sughosh.ganu@linaro.org Reviewed-by: Simon Glass sjg@chromium.org

---

Changes since V6: None

cmd/Kconfig | 1 + test/dm/rng.c | 29 +++++++++++++++++++++++++++++ 2 files changed, 30 insertions(+)

diff --git a/cmd/Kconfig b/cmd/Kconfig index d5f842136c..76878ce307 100644 --- a/cmd/Kconfig +++ b/cmd/Kconfig @@ -1961,6 +1961,7 @@ config CMD_GETTIME config CMD_RNG bool "rng command" depends on DM_RNG

•   default y if SANDBOX
    select HEXDUMP
    help
      Print bytes from the hardware random number generator.
  

diff --git a/test/dm/rng.c b/test/dm/rng.c index 5b34c93ed6..6d1f68848d 100644 --- a/test/dm/rng.c +++ b/test/dm/rng.c @@ -25,3 +25,32 @@ static int dm_test_rng_read(struct unit_test_state *uts) return 0; } DM_TEST(dm_test_rng_read, UT_TESTF_SCAN_PDATA | UT_TESTF_SCAN_FDT);

+/* Test the rng command */ +static int dm_test_rng_cmd(struct unit_test_state *uts) +{

•   struct udevice *dev;
  

•   ut_assertok(uclass_get_device(UCLASS_RNG, 0, &dev));
  

•   ut_assertnonnull(dev);
  

•   ut_assertok(console_record_reset_enable());
  

•   run_command("rng", 0);
  

•   ut_assert_nextlinen("00000000:");
  

•   ut_assert_nextlinen("00000010:");
  

•   ut_assert_nextlinen("00000020:");
  

•   ut_assert_nextlinen("00000030:");
  

•   ut_assert_console_end();
  

•   run_command("rng 0 10", 0);
  

•   ut_assert_nextlinen("00000000:");
  

•   ut_assert_console_end();
  

•   run_command("rng 20", 0);
  

•   ut_assert_nextlinen("No RNG device");
  

•   ut_assert_console_end();
  

•   return 0;
  

+}

+DM_TEST(dm_test_rng_cmd, UT_TESTF_SCAN_PDATA | UT_TESTF_SCAN_FDT | UT_TESTF_CONSOLE_REC);

2.34.1

Acked-by: Ilias Apalodimas ilias.apalodimas@linaro.org